First iteration of minor corrections
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@ -9,7 +9,7 @@ Computer arbeiten. Einige Benutzer:innen empfinden jedoch irgendwann Unbehagen
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oder sogar Schmerzen bei der Verwendung einer Tastatur, da die Finger viele
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kleine und sich wiederholende Bewegungen ausführen müssen, um die Tasten zu
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bedienen. Daher versuchen wir in dieser Bachelorarbeit, ein alternatives, nicht
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uniformes Tastaturdesign zu evaluieren, bei dem jede einzelne mechanische Taste
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uniformes Tas\-taturdesign zu evaluieren, bei dem jede einzelne mechanische Taste
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mit einer Feder ausgestattet ist, die einen Widerstand aufweist, der dem
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spezifischen Finger entspricht, der sie normalerweise bedient. Die Idee hinter
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diesem angepassten Design ist, insbesondere die schwächeren Finger zu entlasten
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@ -19,13 +19,13 @@ Finger angepassten Betätigungskraft einen positiven Einfluss auf die Effizienz
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und die allgemeine Zufriedenheit während der Benutzung hat. Darum haben wir die
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aktuelle Verfügbarkeit von Widerständen für mechanische Tastenschalter evaluiert
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und eine erste telefonische Befragung (n = 17) durchgeführt, um Präferenzen,
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Anwendungsfälle und bisherige Erfahrungen mit Tastaturen zu ermitteln. Darüber
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Anwendungsfälle und bisherige Erfahrungen mit Tas\-taturen zu ermitteln. Darüber
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hinaus führten wir ein weiteres Experiment durch, bei dem wir die maximal
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ausübbare Kraft für jeden Finger in verschiedenen, mit dem Drücken einer Taste
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verbundenen Positionen maßen und im Anschluss als Grundlage für unser
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angepasstes Tastaturdesign verwendeten. Schließlich wurden in einer dreiwöchigen
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Laborstudie mit 24 Teilnehmern das angepasste Tastaturdesign und drei
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herkömmliche Tastaturen mit 35 g, 50 g und 80 g Betätigungskraft in Bezug auf
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herkömmliche Tastaturen mit 35\,g, 50\,g und 80\,g Betätigungskraft in Bezug auf
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Leistung und allgemeine Zufriedenheit miteinander verglichen. Die statistische
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Auswertung ergab, dass vor allem die Fehlerquote durch höhere Betätigungskräfte
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positiv beeinflusst wird und dass Tastaturen mit weder zu hohem noch zu geringem
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@ -39,4 +39,4 @@ das angepasste Design aufgrund der gleich guten Ergebnisse immer noch eine
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brauchbare Alternative ist und mit weiteren Verbesserungen, z. B. einer
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vollständigen Personalisierung des Federwiderstands für jede Taste,
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möglicherweise das Erlebnis bei der Verwendung und die Leistung für
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anspruchsvolle Benutzer:innen verbessern könnte.
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anspruchsvolle Benutzer:innen verbessert werden könnte.
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@ -20,12 +20,12 @@ with keyboards. Further, we ran another preliminary experiment, where we
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measured the maximum applicable force for each finger in different positions
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related to keyboarding as a basis for our adjusted keyboard design. Lastly,
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during a three week laboratory user study with twenty-four participants, the
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adjusted keyboard design and three traditional keyboards with 35 g, 50 g and 80
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g actuation force where compared to each other in terms of performance and user
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adjusted keyboard design and three traditional keyboards with 35\,g, 50\,g and 80
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g actuation force were compared to each other in terms of performance and user
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satisfaction. The statistical analysis revealed, that especially error rates are
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positively influenced by higher actuation forces and that keyboards with neither
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to heavy nor to light resistance generally perform the best in terms of typing
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speed. Further, the adjusted keyboard and the 50 g keyboard performed almost
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too heavy nor to light resistance generally perform the best in terms of typing
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speed. Further, the adjusted keyboard and the 50\,g keyboard performed almost
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identically in all tests and therefore we could not derive any significant
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improvements in performance or satisfaction over traditional designs that
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utilize keyswitches with moderate resistance. However, we concluded, that with
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@ -28,7 +28,7 @@
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\pagebreak
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\subsection{UX-Curves for All Participants and All Groups}
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\subsection{\Gls{UX Curve}s for All Participants and All Groups}
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\label{app:uxc}
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\begin{figure}[H]
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@ -42,4 +42,12 @@
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\begin{figure}[H]
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\centering
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\includegraphics[width=1.0\textwidth]{images/collage}
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\end{figure}
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\end{figure}
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\subsection{The Four Test Keyboards}
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\label{app:equipment}
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\begin{figure}[H]
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\centering
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\includegraphics[width=1.0\textwidth]{images/keyboards}
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\end{figure}
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212
chap0/sec1.tex
212
chap0/sec1.tex
@ -1,212 +0,0 @@
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% Chapter 0 - Proposal
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% Section 1 - Motivation, problem statement and thesis objectives
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\section{Bachelor Thesis Proposal - Philip Gaber}
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{\huge Impact of adjusted, per key, actuation force on efficiency and satisfaction while using mechanical keyboards}
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\subsection{Motivation}
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In recent years, computers are used to some extend in almost every industry in
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Europe \cite{eurostat_ent_w_comp} and China \cite{iresearch_ent_w_comp}. This
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leads to the conclusion, that also other countries must have a high usage of
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computers in corporations. Furthermore, according to a statistic published by
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\citeauthor{itu_hh_w_comp} in 2019, nearly half of the worldwide households have
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access to at least one computer \cite{itu_hh_w_comp}. One of the most used
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devices for data input while operating a computer is the keyboard
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\parencite[22]{handbook_chi}. Therefore, people who use a computer, either at
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home or to fulfill certain tasks at work, are also likely to use a keyboard. An
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important part of a keyboard is the keyswitch also called keyboard key or
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key. Those keyswitches use, depending on the manufacturer or keyboard type,
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different mechanisms to actuate a keypress. More commonly used mechanism to date
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are scissor switches, mostly used in laptop keyboards, dome/membrane switches,
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often used in low- to mid-priced keyboards, and mechanical switches which are
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the main switch type for high-priced and gaming keyboards
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\cite{ergopedia_keyswitch}. Depending on the mechanism and type of key used, it
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is possible that different force has to be applied to the key to activate
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it. Normally, the force required to activate a key is identical for each key
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across the keyboard. However, previous research has shown, that there is a
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disparity in force generated by different fingers
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\cite{bretz_finger_force}. This raises the question, why there are no keyboards
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for personal or work related use cases with adjusted actuation forces per finger
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or even customizable keyboards, where an individual can select the actuation
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force for each keyswitch individually.
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\subsection{Proposed Objective, Research Question and Hypothesis}
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% This thesis is intended to provide an overview of already conducted research in
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% the domain of keyboards, especially in connection with actuation force and the
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% impact of different keyswitches on keyboard users.
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% Because there is no previous research in the particular field of per finger/key
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% actuation force for (mechanical) keyboards and the impact of such customization
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% on efficiency and comfort, this thesis is also intended to research if this is a
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% viable option in comparison to the classic keyboard with uniform actuation
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% force. Therefore the author proposes to answer the question:
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This thesis is intended to research if a keyboard with zones of keys, which have
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adjusted actuation force depending on the assigned finger for that zone and the
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position on the keyboard, is a viable option compared to the standard keyboard
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with uniform actuation force across all keyswitches.
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\begin{tabular}{p{0.3cm} p{0.5cm} p{13cm} p{0.5cm}}
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& \textbf{\large RQ} & {\Large Does an adjusted actuation force per key have a positive impact on efficiency and overall satisfaction while using a mechanical keyboard?} & \\
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\end{tabular}
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\vspace{1em}
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% TODO: Dissatisfied statt comfort da hohe error rate und dadurch frustriert
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% TODO: Bei hypothesen noch error rate bei geschwindigkeit mit einbeziehen
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% ASK: Doch noch comfort mit einbeziehen?
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\begin{longtable}{p{0.3cm} p{0.5cm} p{13cm} p{0.5cm}}
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& \textbf{H1} & Lower key actuation force improves typing speed over higher key actuation force (efficiency - speed). & \\
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& & & \\
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& \textbf{H2} & Higher key actuation force decreases typing errors compared to lower key actuation force (efficiency - error rate). & \\
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& & & \\
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& \textbf{H3} & Keys with lower actuation force are perceived as more satisfactory to write with than keys with higher actuation force. & \\
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& & & \\
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& \textbf{H4} & Users perform better and feel more satisfied while using Keyboards with adjusted key actuation force than without the adjustment. & \\
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\end{longtable}
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\section{Proposed Method}
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\subsection{Subjects}
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It is planned to recruit 20 participants in total. Main target group to recruit
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participants for the research study from are personal contacts and fellow
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students. Participants are required to type with more than just one finger per
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hand. Thus, touch typing is not a mandatory but helpful skill to
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participate. The age distribution for the subjects is estimated to be between 18
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and 56 years. The average typing speed should be known prior to the main
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experiment. Therefore, a typing speed test should be performed on the subject's
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own keyboard in beginning of the experiment. This typing test has to be
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performed within the standardized test environment consisting of an adjustable
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chair, desk, monitor and the typing test software used within the main
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experiment. Also, all subjects have to give their written consent to
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participate in the study.
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\subsection{Study design}
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Participants must complete several typing tests using four different keyboards.
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The experiment should consist of a experimental group and a control group. The
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control group will perform all typing tests with the same keyboard. The text
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used for the typing test should be easily understandable. Therefore, the text
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has to be evaluated with the help of a \gls{FRE} \cite{flesch_fre}
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adjusted for German language \cite{immel_fre}.
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\begin{equation}\label{fre_german}
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FRE_{deutsch} = 180 - \underbrace{ASL}_{\mathclap{\text{Average Sentence Length}}} - (58,5 * \overbrace{ASW}^{\mathclap{\text{Average Syllables per Word}}})
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\end{equation}
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The adjusted formula (\ref{fre_german}) to estimate the understandability of the
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texts used in this experiment usually yields a number in the range of
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\([0;100]\) called the \gls{FRE}. Higher \gls{FRE}s refer to better
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understandability and thus the texts used in this experiment all have to fulfill
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the requirement of a \gls{FRE} \(> 70\), which represents a fairly easy text
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\cite{immel_fre} and \cite{flesch_fre}.
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One typing test will consist of several smaller, randomly chosen, texts
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snippets. The length of the snippets has to be between 100 and 400 characters
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and a snippet has to meet the \gls{FRE} requirement. The snippets are generated by
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volunteers via the web interface of the platform used in this experiment which
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can be seen in appendix \ref{app:gott}.
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% ASK: Should there be a control group at all, if so should they use their own keyboard or always the same random keyboard while they think they are testing different keyswitches?
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After each typing test, the participant has to fill out an adjusted CEN ISO/TS
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9241-411:2014 keyboard comfort questionnaire \cite{iso9241-411}. One additional
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question was added to this questionnaire: ``How satisfied have you been with
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this keyboard?'' The answer for this question can be selected with the help of a
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\gls{VAS} ranging from 0 to 100 \cite{lewis_vas}.
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\textbf{Planned experiment procedure: (Total time requirement: 120 min)}
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\begin{enumerate}
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\item Pre-Test questionnaire to gather demographic and other relevant
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information e.g., touch typist, average \gls{KB} usage per day, predominantly
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used keyboard type, previous medical conditions affecting the result of the
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study e.g., \gls{RSI}, \gls{CTS}, etc. The full questionnaire can be observed
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in the appendix \ref{app:gott}. (5 min)
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\item Adjustment of the test environment (Chair height, monitor height, etc.) (2 min)
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\item Prepare subject for \gls{EMG} measurements: Electrodes are placed on the
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\gls{FDS}/\gls{FDP} and \gls{ED} of both forearms. The main function of the
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\gls{FDS} and \gls{FDP} is the flexion of the medial four digits, while the
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\gls{ED} mainly extends the medial four digits. Therefore, these muscles are
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primarily involved in the finger movements required for typing on a keyboard
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\cite{netter_anatomy}. (8 min)
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\item Familiarization with the typing test and keyboard model used in the experiment. All participants use the same keyboard with 50g actuation force for this step. (5 min)
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\item Initial typing test with own keyboard. (5 min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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% SUBTOTAL: 30 min
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\item \textbf{Main Test (H1-H4):} In this part the subject has to
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take two, 5 minute, typing tests per keyboard, with a total of 4
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keyboards (\gls{KB} A, \gls{KB} B, \gls{KB} C, \gls{KB} D). After each
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typing test, the subject has to fill out the post typing test keyboard
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comfort questionnaire. Keyboards A, B and C are equipped with one set of
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keyswitches and therefore each of the keyboards provides one of the
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following, uniform, actuation forces across all keyswitches: 35 \gls{g},
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50 \gls{g} or 80 \gls{g}. These specific values are the results of a
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self conducted comparison between the product lines of most major
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keyswitch manufacturers. The results shown in appendix
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\ref{app:keyswitch} yield, that the lowest broadly available force for
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keyswitches is 35 \gls{g}, the highest broadly available force is 80
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\gls{g}, and the most common offered force is 50 \gls{g}. Keyboard D is
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equipped with different zones of keyswitches that use appropriate
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actuation forces according to finger strength differences and key
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position. The keyboards used in this experiment are visually identical,
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ISO/IEC 9995-1 conform \cite{iso9995-1} and provide a \gls{QWERTZ}
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layout to resemble the subjects day-to-day layout and keyboard format as
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close as possible. All keyboards are equipped with linear mechanical
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keyswitches from one manufacturer to minimize differences in haptic and
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sound while typing. To mitigate order effects, the order of the
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keyboards is counterbalanced with the help of the latin square method
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and the text snippets for the individual tests are randomized
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\cite{statist_counterbalancing}. \textbf{(total: 80 min)}
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\begin{enumerate}
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\item \textbf{\gls{KB} A, Part 1:} Typing test. (5min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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\item \textbf{\gls{KB} A, Part 2:} Typing test. (5min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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\item \textbf{\gls{KB} C, Part 1:} Typing test. (5min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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\item \textbf{\gls{KB} C, Part 2:} Typing test. (5min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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\item \textbf{\gls{KB} B, Part 1:} Typing test. (5min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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\item \textbf{\gls{KB} B, Part 2:} Typing test. (5min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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\item \textbf{\gls{KB} D, Part 1:} Typing test. (5min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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\item \textbf{\gls{KB} D, Part 2:} Typing test. (5min) \\
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Adjusted follow-up ISO keyboard comfort questionnaire. (2 min) \\
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Pause with light stretching exercises. (3 min)
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\end{enumerate}
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\item Post-Test semi-structured interview: The participant has to draw three
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different UX curves \cite{kujala_ux_curve} to evaluate how fatigue,
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performance and overall usability of the individual keyboards were perceived
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during the experiment. While drawing the UX curve, participants should
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describe their thought process. To reduce errors in the later evaluation of
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the UX curves, the entire interview is recorded. (10 min)
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\end{enumerate}
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The \gls{EMG} data for all muscles is captured using the Flexvolt Chrome app and Flexvolt 8-Channel
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biosensor device in combination with TIGA-MED ECD-Electrodes. The captured data is then processed and
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plotted using Python. Hardware and plots can be observed in Figure \ref{fig:emg_setup}.
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\begin{figure}[h]
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\centering
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\includegraphics[width=1.0\textwidth]{images/emg_setup.jpg}
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\caption{Flexvolt 8-Channel Biosensor and example plots of \gls{EMG} data}
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\label{fig:emg_setup}
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\end{figure}
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This test scenario is inspired by the tests conducted in \cite{kim_typingforces}.
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@ -29,11 +29,11 @@
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In recent decades, computers and other electronic devices have become an
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indispensable part of everyday life. Computers are used in almost every industry
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\cite{iresearch_ent_w_comp, eurostat_ent_w_comp} and 84\% of European households
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as well as nearly half of the worldwide households have access to at least one
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computer \cite{eurostat_hous_w_comp, itu_hh_w_comp}. Even 153 years after the
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first typewriter was patented \cite{noyes_qwerty} people still mostly use
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identical looking keyboards as their main way to input data into a computer
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\cite{iresearch_ent_w_comp, eurostat_ent_w_comp} and 84\,\% of European
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households as well as nearly half of the worldwide households have access to at
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least one computer \cite{eurostat_hous_w_comp, itu_hh_w_comp}. Even 153 years
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after the first typewriter was patented \cite{noyes_qwerty} people still mostly
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use identical looking keyboards as their main way to input data into a computer
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\parencite[22]{handbook_chi} \& \cite{broel_dektop_or_smartphone}. A potential
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problem while interacting with a computer through the usage of a keyboard are
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rapid movements of the fingers over a prolonged time, which can cause discomfort
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@ -42,29 +42,29 @@ and increase the risk for \gls{WRUED} \cite{pascarelli_wrued,
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is the force required to generate a keypress, is directly related to the actual
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force an individual generates to press a specific key
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\cite{gerard_keyswitch}. Also, the individual fingers are not capable of
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exerting identical force and therefore fatigue must be higher for weaker fingers
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exerting identical force, which could lead to higher fatigue in weaker fingers
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\cite{bretz_finger, martin_force, baker_kinematics, dickson_finger}. There are
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various designs for alternative keyboards by e.g.,
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Maltron\footnote{\url{https://www.maltron.com/store/c47/Dual_Hand_Keyboards.html}},
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Ergodox\footnote{\url{https://www.ergodox.io/}}, Kenesis
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\footnote{\url{https://kinesis-ergo.com/keyboards/advantage2-keyboard/}},
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etc. which, because of the often unusual layouts and extra keys for the thumbs,
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all require the typist to adjust to a completely new way of typing and therefore
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could reduce productivity during this adjustment phase. Additionally, a study by
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Baker et al. (n = 77) revealed, that even after several months of using a
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keyboard with an alternative design, in terms of usability, participants still
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preferred the traditional design because of its superb usability
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\cite{baker_ergo2}. With these insights, the uniformity of actuation force
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across conventional keyboards may be a potential characteristic that could be
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improved on, to reduce the strain on weaker fingers and thus reduce fatigue and
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increase comfort. Therefore, a keyboard with, per key, adjusted actuation force,
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depending on the finger usually operating the key, might be a feasible solution
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without the requirement for typists to invest in higher priced alternative
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keyboards, which also require additional familiarization. To become a successful
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alternative, the adjusted keyboard design has to perform equally good or even
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better than existing conventional keyboard designs, while also enhancing the user
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experience during usage. These requirements led to the research question of
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this thesis:
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etc. Due to the oftentimes unusual layouts and extra keys for the thumbs, all
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these keyboards require the typist to adjust to a completely new way of typing
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and therefore could reduce productivity during this adjustment
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phase. Additionally, a study by Baker et al. (n = 77) revealed, that even after
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several months of using a keyboard with an alternative design, in terms of
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usability, participants still preferred the traditional design because of its
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superb usability \cite{baker_ergo2}. With these insights, the uniformity of
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actuation force across conventional keyboards may be a potential characteristic
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that could be improved on, to reduce the strain on weaker fingers and thus
|
||||
reduce fatigue and increase comfort. Therefore, a keyboard with, per key,
|
||||
adjusted actuation force, depending on the finger usually operating the key,
|
||||
might be a feasible solution without the requirement for typists to invest in
|
||||
higher priced alternative keyboards, which also require additional
|
||||
familiarization. To become a successful alternative, the adjusted keyboard
|
||||
design has to perform equally good or even better than existing conventional
|
||||
keyboard designs, while also enhancing the user experience during usage. These
|
||||
requirements led to the following research question of this thesis:
|
||||
|
||||
\vspace{1em}
|
||||
\begin{tabular}{p{0.3cm} p{0.5cm} p{13cm} p{0.5cm}}
|
||||
|
||||
@ -17,12 +17,12 @@ results of previous research.
|
||||
\label{sec:wrued}
|
||||
\Gls{WRUED} is a term to describe a group of medical conditions related to
|
||||
muscles, tendons and nerves in shoulder, arm, elbow, forearm or hand, such as
|
||||
e.g., \gls{CTS}, \gls{RSI}, tendonitis, tension neck syndrome, etc. Symptoms of
|
||||
\gls{CTS}, \gls{RSI}, Tendinitis, \gls{TNS}, etc. Symptoms of
|
||||
\gls{WRUED} are aching, tiredness and fatigue of affected regions that either
|
||||
occur while working or even extend to phases of relaxation. A common way to
|
||||
treat \gls{WRUED} is to avoid the potentially harmful activities that cause
|
||||
discomfort in affected areas \cite{ccfohas_wrued}. Pascarelli and Hsu reported,
|
||||
that out of 485 patients with \gls{WRUED} 17\% were computer users
|
||||
that out of 485 patients with \gls{WRUED} 17\,\% were computer users
|
||||
\cite{pascarelli_wrued}. Since computers have become an essential part of many
|
||||
jobs in almost any sector of employment, restrictions of computer related
|
||||
activities would result in either reduced productivity or the complete inability
|
||||
@ -125,9 +125,9 @@ separating the two plates which closes the electrical circuit and sends a
|
||||
keypress to the computer. After the key is released, the spring pushes the stem
|
||||
back to its original position \cite{bassett_keycap, peery_3d_keyswitch,
|
||||
ergopedia_keyswitch, chen_mech_switch}. Usually, mechanical keyswitches are
|
||||
directly soldered onto the \gls{PCB} of the keyboard but there are also
|
||||
keyboards where the \gls{PCB} features special sockets where the keyswitches can
|
||||
be hot-swapped without soldering at all \cite{gmmk_hot_swap}. It is also
|
||||
directly soldered onto the \gls{PCB} of the keyboard. However, there are also
|
||||
keyboards with \gls{PCB}s that feature special sockets where the keyswitches can
|
||||
be \gls{swapped} without soldering at all \cite{gmmk_hot_swap}. It is also
|
||||
possible to equip an already existing \gls{PCB} with sockets to make it
|
||||
hot-swappable \cite{te_connect}.
|
||||
|
||||
@ -147,27 +147,27 @@ primarily define if and how feedback for a keypress is realised:
|
||||
\item \textbf{Tactile Switches} utilize a small bump on the stem to slightly
|
||||
increase and then instantly collapse the force required immediately before the
|
||||
actual actuation happens \cite{cherry_mx_brown}. This provides the typist with
|
||||
a short noticeable haptic feedback and which should encourage a premature
|
||||
a short noticeable haptic feedback, which should encourage a premature
|
||||
release of the key. An early study by Brunner and Richardson suggested, that
|
||||
this feedback leads to faster typing speeds and a lower error rate in both
|
||||
this feedback leads to faster typing speed and a lower error rate in both
|
||||
experienced and casual typists (n=24) \cite{brunner_keyswitch}. Contrary, a
|
||||
study by Akagi yielded no significant differences in terms of speed and error
|
||||
study by Akagi yielded no significant differences in terms of speed nor error
|
||||
rate between tactile and linear keyswitches and links the variation found in
|
||||
error rates to differences in actuation force (n=24)
|
||||
\cite{akagi_keyswitch}. Tactile feedback could still assist the typist to
|
||||
prevent \gls{bottoming}.
|
||||
\item \textbf{Tactile and audible Switches (Clicky)} separate the stem into
|
||||
two parts, the lower part also features a small bump to provide tactile
|
||||
two parts. The lower part also features a small bump to provide tactile
|
||||
feedback and is also responsible for a distinct click sound when the actuation
|
||||
happens \cite{cherry_mx_blue}. Gerard et al. noted, that in their study
|
||||
(n=24), keyboards with audible feedback increased typing speed and decreased
|
||||
(n=24) keyboards with audible feedback increased typing speed and decreased
|
||||
typing force. This improvement could have been due to the previous experience
|
||||
of participants with keyboards of similar model and keyswitch characteristic
|
||||
\cite{gerard_keyswitch}.
|
||||
\item \textbf{Linear Switches} do not offer a distinct feedback for the
|
||||
typist. The activation of the keyswitch just happens after approximately half
|
||||
the total travel distance \cite{cherry_mx_red}. The only tactile feedback that
|
||||
could happen is the impact of \gls{bottoming}, but with enough practice,
|
||||
could happen is the impact of \gls{bottoming}. However, with enough practice
|
||||
typist can develop a lighter touch which reduces overall typing force and
|
||||
therefore reduces the risk of \gls{WRUED} \cite{gerard_keyswitch,
|
||||
peery_3d_keyswitch, fagarasanu_force_training}.
|
||||
@ -192,7 +192,7 @@ forces. Actuation force, also sometimes referred to as make force, is the force
|
||||
required to activate the keyswitch \cite{radwin_keyswitch,
|
||||
ergopedia_keyswitch}. That means depending on the mechanism used, activation
|
||||
describes the closing of an electrical circuit which forwards a signal, that is
|
||||
then processed by a controller inside of the keyboard and finally send to the
|
||||
then processed by a controller inside of the keyboard and finally sent to the
|
||||
computer. The computer then selects the corresponding character depending on the
|
||||
layout used by the user. Previous studies have shown, that actuation force has
|
||||
an impact on error rate, subjective discomfort, muscle activity and force
|
||||
@ -202,7 +202,7 @@ typing speed, which could be more significant with greater variation of
|
||||
actuation force across tested keyboards \cite{loricchio_force_speed}.
|
||||
|
||||
\begin{phga_sum*}
|
||||
Since this thesis is focused around keyboards and especially the relation
|
||||
Since this thesis is focused on keyboards and especially the relation
|
||||
between the actuation force of the keyswitch and efficiency (speed, error rate)
|
||||
and also the differences in satisfaction while using keyswitches with varying
|
||||
actuation forces, it was important to evaluate different options of keyswitches
|
||||
@ -217,14 +217,14 @@ each key should have an adjusted actuation force depending on the finger that
|
||||
normally operates it. It should be mentioned, that it is theoretically possible
|
||||
to exchange individual rubber dome switches on some keyboards, e.g. keyboards
|
||||
with \gls{Topre} switches, but the lacking availability of compatible keyboards
|
||||
and especially the limited selection of actuation forces (30g to 55g for
|
||||
and especially the limited selection of actuation forces (30\,g to 55\,g for
|
||||
\gls{Topre} \cite{realforce_topre}) makes this not a viable option for this
|
||||
thesis \cite{keychatter_topre}. Therefore, we decided to use mechanical
|
||||
keyswitches for our experiment, because these keyswitches are broadly available
|
||||
keyswitches for our experiment. These keyswitches are broadly available
|
||||
in a variety of actuation forces and because the spring which mainly defines the
|
||||
actuation force can be easily replaced with any other compatible spring on the
|
||||
market, the selection of actuation forces is much more appropriate for our use
|
||||
case (30g to 150g) \cite{peery_3d_keyswitch}. We also decided to use linear
|
||||
case (30\,g to 150\,g) \cite{peery_3d_keyswitch}. We also decided to use linear
|
||||
switches because they closest resemble the feedback of the more wide spread
|
||||
rubber dome switches. Further, linear switches do not introduce additional
|
||||
factors beside the actuation force to the experiment. In addition, based on the
|
||||
@ -248,15 +248,16 @@ is transcribed \cite{chen_typing_test, hoffmann_typeright,
|
||||
\subsubsection{Readability of Text}
|
||||
\label{sec:meas_fre}
|
||||
|
||||
Text used should be easy to read for typists
|
||||
participating in studies that evaluate their performance and are therefore is
|
||||
chosen based on a metric called the \gls{FRE} which indicates the
|
||||
understandability of text \cite{fagarasanu_force_training,
|
||||
kim_typingforces, flesch_fre}. The score ranges from 0 which implies very poor reading
|
||||
ease to 100 suggesting that the style of writing used causes the text to be very
|
||||
easy to comprehend \cite{flesch_fre}. Immel proposed an adjusted formula of the
|
||||
\gls{FRE} that is suitable for German text \cite{immel_fre} and can be seen in
|
||||
(\ref{eq:fre_german}).
|
||||
The texts used should be easy to read for typists participating in studies that
|
||||
evaluate their performance and are therefore chosen based on a metric called the
|
||||
\gls{FRE} which indicates the understandability of text
|
||||
\cite{fagarasanu_force_training, kim_typingforces, flesch_fre}. The score ranges
|
||||
from 0 which implies very poor reading ease to 100 suggesting that the style of
|
||||
writing used causes the text to be very easy to comprehend
|
||||
\cite{flesch_fre}. Immel proposed an adjusted formula of the \gls{FRE} that is
|
||||
suitable for German text \cite{immel_fre} and can be seen in
|
||||
(\ref{eq:fre_german}). This formula was necessary, because all participants were
|
||||
Germans.
|
||||
|
||||
\begin{equation}\label{eq:fre_german}
|
||||
FRE_{deutsch} = 180 - \underbrace{ASL}_{\mathclap{\text{Average Sentence Length}}} - (58,5 * \overbrace{ASW}^{\mathclap{\text{Average Syllables per Word}}})
|
||||
@ -344,7 +345,7 @@ In several other studies, in addition to the metrics mentioned so far, \gls{EMG}
|
||||
data was captured to evaluate the muscle activity or applied force while typing
|
||||
on completely different or modified hardware \cite{kim_typingforces,
|
||||
fagarasanu_force_training, gerard_audio_force, gerard_keyswitch, martin_force,
|
||||
rose_force, rempel_ergo, pereira_typing_test}. \gls{EMG} signals, are captured
|
||||
rose_force, rempel_ergo, pereira_typing_test}. \gls{EMG} signals are captured
|
||||
with the help of specialized equipment that utilize electrodes which are either
|
||||
placed onto the skin above the muscles of interest (non-invasive) or inserted
|
||||
directly into the muscle (invasive). The disadvantage of non-invasive surface
|
||||
@ -379,7 +380,7 @@ and satisfaction, are evaluated based on survey data collected after
|
||||
participants used different input methods \cite{kim_typingforces,
|
||||
bell_pauseboard, bufton_typingforces, pereira_typing_test, iso9241-411}. In
|
||||
their study, Kim et al. used a modified version of the \gls{KCQ} provided by the
|
||||
\gls{ISO} which is specifically designed to evaluate different keyboards in
|
||||
\gls{ISO}, which is specifically designed to evaluate different keyboards in
|
||||
terms of user satisfaction, comfort and usability \cite{kim_typingforces,
|
||||
iso9241-411}. This survey poses a total of twelve questions concerning e.g.,
|
||||
fatigue of specific regions of the upper extremity, general satisfaction with
|
||||
@ -392,7 +393,7 @@ categories \cite{nguyen_ueq, olshevsky_ueq, gkoumas_ueq}. While the full
|
||||
(attractiveness, perspicuity, efficiency, dependability, stimulation and
|
||||
novelty), the \gls{UEQ-S} only features 8 questions and two scales (pragmatic
|
||||
and hedonic quality). Because of the limited explanatory power of the
|
||||
\gls{UEQ-S}, it is recommended to only use it, if there is not enough time to
|
||||
\gls{UEQ-S}, it is recommended to only use it if there is not enough time to
|
||||
complete the full \gls{UEQ} or if the participants of a study are required to
|
||||
rate several products in one session \cite{schrepp_ueq_handbook}.
|
||||
|
||||
@ -416,9 +417,9 @@ As already discussed in Section \ref{sec:metrics}, it is common practice in
|
||||
research related to typing to present a text that has to be transcribed by the
|
||||
participant. Usually, the text was chosen by the researcher or already available
|
||||
through the used typing test software. If the understandability of text is of
|
||||
concern, the binary choice of, is understandable or not, made by the researcher
|
||||
concern, the binary choice of―is understandable or not―made by the researcher
|
||||
could lead to a phenomenon called the observer bias \cite{hrob_observer,
|
||||
berger_observer, angrosino_observer}. Thus, the text could potentially be to
|
||||
berger_observer, angrosino_observer}. Thus, the text could potentially be too
|
||||
difficult to understand for the participants if not evaluated with e.g. the
|
||||
\gls{FRE} or other adequate formulas. Further, if there is previous knowledge
|
||||
about the requested participants, the researcher could subconsciously select
|
||||
@ -457,31 +458,31 @@ models. One difference was the applied force, a keyswitch required to
|
||||
activate. A study by Akagi tested the differences in performance and preference
|
||||
across four visually identical keyboards with different keyswitches. The
|
||||
keyswitches differed in actuation force and type. Two keyboards used tactile
|
||||
keyswitches with 70.9 g (\gls{KB} A) and 32.5 g (\gls{KB} C) the other two
|
||||
linear switches with 70.9 g (\gls{KB} D) and 42.5 g (\gls{KB} B). The (n=24)
|
||||
keyswitches with 70.9\,g (\gls{KB} A) and 32.5\,g (\gls{KB} C) the other two
|
||||
linear switches with 70.9\,g (\gls{KB} D) and 42.5\,g (\gls{KB} B). The (n=24)
|
||||
subjects were required to type on each keyboard for 7 to 8 minutes where speed
|
||||
and errors were recorded. The results showed, that \gls{KB} D (linear, 70.9 g)
|
||||
produced the lowest error rate followed by \gls{KB} A (tactile, 70.9 g),
|
||||
\gls{KB} C (linear, 42.5 g) and \gls{KB} B (tactile, 35.5 g). Further, the
|
||||
difference in typing speed between the slowest (tactile, 70.9 g) and fastest
|
||||
(linear, 42.5 g) keyboard was only 2.61\% and according to Akagi too small to be
|
||||
and errors were recorded. The results showed, that \gls{KB} D (linear, 70.9\,g)
|
||||
produced the lowest error rate followed by \gls{KB} A (tactile, 70.9\,g),
|
||||
\gls{KB} C (linear, 42.5\,g) and \gls{KB} B (tactile, 35.5\,g). Further, the
|
||||
difference in typing speed between the slowest (tactile, 70.9\,g) and fastest
|
||||
(linear, 42.5\,g) keyboard was only 2.61\,\% and according to Akagi too small to be
|
||||
significant in practical use. The study also revealed, that the preference for
|
||||
neither of the four keyboards was significantly different
|
||||
\cite{akagi_keyswitch}. A follow up survey by Akagi concerning the model of
|
||||
keyboard typists would prefer to use in the future revealed, that 69\% of the 81
|
||||
participating decided for a newly proposed keyboard with 56.7 g resistance and
|
||||
keyboard typists would prefer to use in the future revealed, that 69\,\% of the 81
|
||||
participating decided for a newly proposed keyboard with 56.7\,g resistance and
|
||||
light tactile feedback \cite{akagi_keyswitch}. Further, a study by Loricchio,
|
||||
were (n=16) participants typed on two identical keyboard models that only
|
||||
differed in actuation force (58 g and 74g), also yielded moderate differences in
|
||||
typing speed. The keyboard with lower actuation force was 8.25\% faster and
|
||||
where (n=16) participants typed on two identical keyboard models that only
|
||||
differed in actuation force (58\,g and 74\,g), also yielded moderate differences in
|
||||
typing speed. The keyboard with lower actuation force was 8.25\,\% faster and
|
||||
preferred by 15 out of the 16 subjects compared to the keyboard featuring
|
||||
keyswitches with higher actuation force \cite{loricchio_force_speed}. A study by
|
||||
Hoffmann et al. even designed a keyboard that utilized small
|
||||
electromagnets―instead of the typically used spring―to dynamically alter the
|
||||
resistance of keys to prevent erroneous input by increasing the force required
|
||||
to press keys that do not make sense in the current context of a word. This
|
||||
design reduced the number of required corrections by 46\% and overall lowered
|
||||
typos by 87\% compared to when the force feedback was turned off (n=12)
|
||||
design reduced the number of required corrections by 46\,\% and overall lowered
|
||||
typos by 87\,\% compared to when the force feedback was turned off (n=12)
|
||||
\cite{hoffmann_typeright}.
|
||||
|
||||
\begin{phga_sum*}
|
||||
@ -490,16 +491,16 @@ different results pertaining speed, but agreed that actuation force influences
|
||||
the error rate during typing related tasks. To our best knowledge, there are no
|
||||
studies that evaluated the effect of non-uniformly distributed actuation forces
|
||||
across one keyboard on speed, accuracy, error rate or preference. This is why we
|
||||
want to reevaluate the influence of actuation force on speed and determine, if
|
||||
want to reevaluate the influence of actuation force on speed and determine if
|
||||
keyboards with non-uniform actuation forces have a positive impact on all
|
||||
metrics mentioned so far. The next section gives insights, into why such
|
||||
metrics mentioned so far. The next section gives insights into why such
|
||||
keyboards could make sense.
|
||||
\end{phga_sum*}
|
||||
|
||||
\subsection{Strength of Individual Fingers}
|
||||
As already mentioned in Section \ref{sec:mech_switch}, the force applied to a
|
||||
keyswitch is the concern of multiple studies that evaluate the relation between
|
||||
keyboarding and \gls{WRUED}. Further, multiple studies came to the conclusion,
|
||||
keyboarding and \gls{WRUED}. Further, multiple studies came to the conclusion
|
||||
that there is a significant discrepancy in strength between individual fingers
|
||||
\cite{bretz_finger, martin_force, baker_kinematics, dickson_finger}. Bretz et
|
||||
al. found, that when participants squeezed an object between thumb and finger,
|
||||
@ -519,7 +520,7 @@ The goal of this thesis is to evaluate the possible advantages of keyboards with
|
||||
non-uniform actuation forces. The fairly small difference of only 0.08 \gls{N} in mean
|
||||
force applied to keyboards recorded by Martin et al. \cite{martin_force} but
|
||||
rather big difference in finger strength measured by Bretz et
|
||||
al. \cite{bretz_finger} could indicate, that albeit the difference in strength,
|
||||
al. \cite{bretz_finger} could indicate that albeit the difference in strength,
|
||||
all fingers have to apply equal force to generate a keypress because of the
|
||||
uniform actuation force used in commercially available keyboards.
|
||||
\end{phga_sum*}
|
||||
@ -546,9 +547,9 @@ is feasible to evaluate possible alternative input methods to the more
|
||||
traditional keyboard. The availability of affordable surface level \gls{EMG}
|
||||
measurement devices makes it possible for researchers that are not medically
|
||||
trained to conduct non-invasive muscle activity measurements \cite{takala_emg}
|
||||
and load cells in combination with micro controllers are a reliable, low-cost
|
||||
solution to visualize the strength of different fingers and monitor applied
|
||||
forces while typing \cite{gerard_keyswitch, rempel_ergo,
|
||||
In addition, load cells in combination with micro controllers are a reliable,
|
||||
low-cost solution to visualize the strength of different fingers and monitor
|
||||
applied forces while typing \cite{gerard_keyswitch, rempel_ergo,
|
||||
bufton_typingforces}. Although, the strength of individual fingers has already
|
||||
been measured in different studies \cite{bretz_finger, martin_force,
|
||||
baker_kinematics, dickson_finger}, to our best knowledge, there are no
|
||||
|
||||
@ -1,12 +1,12 @@
|
||||
\section{Development and Implementation of Necessary Tools}
|
||||
For the purpose of this thesis, we programmed our own typing test platform to
|
||||
have better control over the performance related measurements and the text that
|
||||
has to be transcribed. Further, the participants had to fill out up to two
|
||||
questionnaires after each typing test which had to be linked to this specific
|
||||
typing test or keyboard. With a total number of 24 subjects, five keyboards and
|
||||
therefore 10 individual typing tests per subject or 240 typing tests in total,
|
||||
we decided to incorporate a questionnaire feature into our platform to mitigate
|
||||
the possibility of false mappings between typing tests, surveys and
|
||||
has to be transcribed. The participants had to fill out up to two questionnaires
|
||||
after each typing test which had to be linked to this specific typing test or
|
||||
keyboard. With a total number of 24 subjects, five keyboards and therefore 10
|
||||
individual typing tests per subject or 240 typing tests in total, we decided to
|
||||
incorporate a questionnaire feature into our platform to mitigate the
|
||||
possibility of false mappings between typing tests, surveys and
|
||||
participants. Additionally, because we wanted to control the understandability
|
||||
of text without introducing observer bias for the text selection process and
|
||||
also to save time, we implemented a crowdsourcing feature where individuals
|
||||
@ -34,7 +34,7 @@ as shown in Figure \ref{fig:s3_flow}
|
||||
\label{sec:gott}
|
||||
The platform we created is called \gls{GoTT} because the backend, which is the
|
||||
server side code, is programmend in Go, a programming language developed by a
|
||||
team at Google \cite{golang}. The decision for Go was made, because Go's
|
||||
team at Google \cite{golang}. The decision for Go was made because Go's
|
||||
standard library offers convenient packages to quickly setup a web server with
|
||||
simple routing and templating functionalities \cite{golang_std}. The backend and
|
||||
frontend communicate through a \gls{REST} \gls{API} and exchange data in
|
||||
@ -144,7 +144,8 @@ KSPS = roundToPrecision((ISL - 1) / TEST_TIME, 5);
|
||||
% KSPC = roundToPrecision(ISL / TL, 5);
|
||||
|
||||
For further implementation details on how input was captured or sent to the
|
||||
backend refer to the code in the online repository \footnote{TODO: GITHUB}.
|
||||
backend, refer to the code in the online
|
||||
repository\footnote{\url{https://github.com/qhga/GoTT}}.
|
||||
|
||||
To test the usability of the typing test, we asked five individuals to complete
|
||||
multiple typing tests with their own computer. Based on the feedback we
|
||||
@ -209,7 +210,7 @@ not. The implementation of the algorithm that calculates the \gls{FRE} can be
|
||||
seen in Listing \ref{lst:gott_fre}. The function \textit{countSyllables}
|
||||
utilizes regex \footnote{\url{https://github.com/google/re2/wiki/Syntax}}
|
||||
matching to identify the number of syllables in a given string in German
|
||||
language. The rules for hyphenation defined by Duden online
|
||||
language. The rules for hyphenation defined by \textit{Duden Online}
|
||||
\footnote{\url{https://www.duden.de/sprachwissen/rechtschreibregeln/worttrennung}}
|
||||
were used to derive the regex patterns to identify syllables
|
||||
\cite{duden_hyphen}. The \gls{FRE} scores yielded by our function were verified
|
||||
@ -276,7 +277,10 @@ func calculateFRE(txt string) float64 {
|
||||
\begin{figure}[ht]
|
||||
\centering
|
||||
\includegraphics[width=0.8\textwidth]{images/force_master_1}
|
||||
\caption{Prototype of a measuring device that simulates the distance and finger position required to press different keys on a keyboard. The display shows the currently applied force in gram and the peak force applied throughout the current measurement in gram and \gls{N}}
|
||||
\caption{Prototype of a measuring device that simulates the distance and
|
||||
finger position required to press different keys on a keyboard. The display
|
||||
shows the currently applied force in gram and the peak force applied
|
||||
throughout the current measurement in gram and \gls{N}}
|
||||
\label{fig:force_master}
|
||||
\end{figure}
|
||||
|
||||
@ -300,7 +304,7 @@ applied force in gram and peak force in gram and \gls{N}. The devices was mainly
|
||||
controlled via two terminal commands. One command initiated re-calibration that
|
||||
was used after each participant or in between measurements and the other command
|
||||
reset all peak values displayed via the display. The base of the device featured
|
||||
a scale, which was traversed with the help of a wrist wrest that got aligned
|
||||
a scale, which was traversed with the help of a wrist rest that got aligned
|
||||
with the markings corresponding to the currently measured key. Each mark
|
||||
represents the distance and position of a finger to the associated key indicated
|
||||
by the label underneath the marking. The measurement process is explained in
|
||||
|
||||
@ -40,17 +40,17 @@ why we wanted to ascertain if and how, with the advance of technology in recent
|
||||
years and especially the capabilities modern smartphones offer, keyboard usage
|
||||
has changed. Further, we wanted to gather information about the preference of
|
||||
key resistance, keyswitch type and experiences with \gls{WRUED}. Therefore, we
|
||||
conducted a structured interview with seventeen volunteers (59\% females) via
|
||||
conducted a structured interview with seventeen volunteers (59\,\% females) via
|
||||
telephone, from which the most important results are presented in Figure
|
||||
\ref{fig:res_tel}. The age of the subjects ranged between 22 and 52 with a mean
|
||||
age of 29 years. The professions of subjects were distributed among medical
|
||||
workers, students, office employees, computer engineers and community
|
||||
workers. The first question we asked was \textit{``Which keyboard in terms of
|
||||
actuation force would be the most satisfying for you to use in the long
|
||||
run?''}. Thirteen (76\%) out of the seventeen subjects mentioned, that they
|
||||
run?''}. Thirteen (76\,\%) out of the seventeen subjects mentioned, that they
|
||||
would prefer a keyboard with light actuation force over a keyboard with higher
|
||||
resistance. The next question \textit{``Have you ever had pain when using a
|
||||
keyboard and if so, where did you have pain?''} yielded, that 41\% of those
|
||||
keyboard and if so, where did you have pain?''} yielded, that 41\,\% of those
|
||||
polled experienced pain at least once while using a keyboard. The areas affected
|
||||
described by the seven who already experienced pain were the wrist
|
||||
\underline{and} forearm (3 out of 7), wrist only (2 out of 7), fingers (1 out of
|
||||
@ -68,7 +68,7 @@ durations related to computer work can be inaccurate
|
||||
prefer to perform with a keyboard rather than your mobile phone?''} revealed,
|
||||
that all of the subjects preferred to use a keyboard when entering greater
|
||||
amounts of data (emails, applications, presentations, calculations, research),
|
||||
but also surprisingly 41\% preferred to use a keyboard to write instant messages
|
||||
but also surprisingly 41\,\% preferred to use a keyboard to write instant messages
|
||||
(chatting via Whatsapp Web\footnote{\url{https://web.whatsapp.com/}}, Signal
|
||||
Desktop\footnote{\url{https://signal.org/download/}}, Telegram
|
||||
Desktop\footnote{\url{https://desktop.telegram.org/}}).
|
||||
@ -90,14 +90,14 @@ Matias\footnote{\url{http://matias.ca/switches/}},
|
||||
Razer\footnote{\url{https://www.razer.com/razer-mechanical-switches}} and
|
||||
Logitech\footnote{\url{https://www.logitechg.com/en-us/innovation/mechanical-switches.html}}. Since
|
||||
some of the key actuation forces listed on the manufacturers or resellers
|
||||
websites were given in cN and most of them in g or gf, the values were adjusted
|
||||
to gram to reflect a trend that is within a margin of ± 2 g of accuracy. The
|
||||
results shown in Figure \ref{fig:keyswitches_brands} are used to determine the
|
||||
minimum, maximum and most common actuation force for broadly available
|
||||
keyswitches. According to our findings, the lowest commercially available
|
||||
actuation force is 35 g ($\approx$ 0.34 \gls{N}) the most common one is 50 g
|
||||
($\approx$ 0.49 \gls{N}) and the highest resistance available is 80 g ($\approx$
|
||||
0.78 \gls{N}).
|
||||
websites were given in \gls{cN} and most of them in gram or gram-force, the values
|
||||
were adjusted to gram to reflect a trend that is within a margin of ± 2\,g of
|
||||
accuracy. The results shown in Figure \ref{fig:keyswitches_brands} are used to
|
||||
determine the minimum, maximum and most common actuation force for broadly
|
||||
available keyswitches. According to our findings, the lowest commercially
|
||||
available actuation force is 35\,g ($\approx$ 0.34 \gls{N}) the most common one
|
||||
is 50\,g ($\approx$ 0.49 \gls{N}) and the highest resistance available is 80\,g
|
||||
($\approx$ 0.78 \gls{N}).
|
||||
|
||||
\begin{figure}[H]
|
||||
\centering
|
||||
@ -107,33 +107,35 @@ actuation force is 35 g ($\approx$ 0.34 \gls{N}) the most common one is 50 g
|
||||
\end{figure}
|
||||
|
||||
\subsection{Preliminary Study of Finger Strength}
|
||||
To evaluate the impact of an adjusted keyboard (keyboard with non-uniform
|
||||
actuation forces) on performance and satisfaction we first needed to get an
|
||||
understanding on how to distribute keyswitches with different actuation forces
|
||||
across a keyboard. Our first idea was to use a similar approach to the keyboard
|
||||
we described in Section \ref{sec:lr_sum}, were the force required to activate
|
||||
the keys decreased towards the left and right ends of the keyboard. This rather
|
||||
simple approach only accounts for the differences in finger strength when all
|
||||
fingers are in the same position, but omits possible differences in applicable
|
||||
force depending on the position a finger has to enter to press a certain key.
|
||||
To detect possible differences in peak force depending on the position of the
|
||||
fingers, we conducted an experiment with six volunteers (50\%
|
||||
females). Subject's ages ranged from 20 to 26 with a mean age of 24 years. The
|
||||
subjects were all personal contacts. Subjects professions were distributed as
|
||||
follows: computer science students (3/6), physiotherapist (1/6), user experience
|
||||
consultant (1/6) and retail (1/6). All Participants were given instructions to
|
||||
exert maximum force for approximately one second onto the key mounted to the
|
||||
measuring device described in Section \ref{sec:force_meas_dev}. We also used a
|
||||
timer to announced when to press and when to stop. We provided a keyboard to
|
||||
every participant, which was used as a reference for the finger position before
|
||||
every measurement. To reduce order effects, we used a balanced latin square to
|
||||
specify the sequence of rows (top, home, bottom) in which the participants had
|
||||
to press the keys \cite{bradley_latin_square}. Additionally, because there were
|
||||
only six people available, we alternated the direction from which participants
|
||||
had to start in such a way, that every second subject started with the little
|
||||
finger instead of the index finger. An example of four different positions of
|
||||
the finger while performing the measurements for the keys \textit{Shift, L, I}
|
||||
and \textit{Z} can be observed in Figure \ref{fig:FM_example}.
|
||||
\label{sec:meth_force}
|
||||
To evaluate the impact of an adjusted keyboard\footnote{keyboard with
|
||||
non-uniform actuation forces} on performance and satisfaction we first needed
|
||||
to get an understanding on how to distribute keyswitches with different
|
||||
actuation forces across a keyboard. Our first idea was to use a similar approach
|
||||
to the keyboard we described in Section \ref{sec:lr_sum}, were the force
|
||||
required to activate the keys decreased towards the left and right ends of the
|
||||
keyboard. This rather simple approach only accounts for the differences in
|
||||
finger strength when all fingers are in the same position, but omits possible
|
||||
differences in applicable force depending on the position a finger has to enter
|
||||
to press a certain key. To detect possible differences in peak force depending
|
||||
on the position of the fingers, we conducted an experiment with six volunteers
|
||||
(50\,\% females). Subject's ages ranged from 20 to 26 with a mean age of 24
|
||||
years. The subjects were all personal contacts. Subjects professions were
|
||||
distributed as follows: computer science students (3/6), physiotherapist (1/6),
|
||||
user experience consultant (1/6) and retail (1/6). All Participants were given
|
||||
instructions to exert maximum force for approximately one second onto the key
|
||||
mounted to the measuring device described in Section
|
||||
\ref{sec:force_meas_dev}. We also used a timer to announced when to press and
|
||||
when to stop. We provided a keyboard to every participant, which was used as a
|
||||
reference for the finger position before every measurement. To reduce order
|
||||
effects, we used a balanced latin square to specify the sequence of rows (top,
|
||||
home, bottom) in which the participants had to press the keys
|
||||
\cite{bradley_latin_square}. Additionally, because there were only six people
|
||||
available, we alternated the direction from which participants had to start in
|
||||
such a way, that every second subject started with the little finger instead of
|
||||
the index finger. An example of four different positions of the finger while
|
||||
performing the measurements for the keys \textit{Shift, L, I} and \textit{Z} can
|
||||
be observed in Figure \ref{fig:FM_example}.
|
||||
|
||||
\begin{figure}[H]
|
||||
\centering
|
||||
@ -148,7 +150,7 @@ and \textit{Z} can be observed in Figure \ref{fig:FM_example}.
|
||||
\end{figure}
|
||||
|
||||
The results of the measurements are given in Table \ref{tbl:finger_force}. The
|
||||
median of the means (15.47 N) of all measurements was used to calculate the
|
||||
median of the means (15.47\,N) of all measurements was used to calculate the
|
||||
actuation forces in gram for the keyswitches later incorporated in the layout
|
||||
for the adjusted keyboard. We used Eq. (\ref{eq:N_to_g}) and
|
||||
Eq. (\ref{eq:actuation_forces}) to calculate the theoretical gram values for
|
||||
@ -156,7 +158,7 @@ each measured keyswitch.
|
||||
|
||||
\begin{equation}
|
||||
\label{eq:N_to_g}
|
||||
GFR = \frac{50 g}{M_{maf}} = \frac{50 g}{14.47 N} = 3.23 \frac{g}{N}
|
||||
GFR = \frac{50\,g}{M_{maf}} = \frac{50\,g}{14.47\,N} = 3.23 \frac{g}{N}
|
||||
\end{equation}
|
||||
|
||||
\begin{equation}
|
||||
@ -164,7 +166,7 @@ each measured keyswitch.
|
||||
AF_{key} = GFR * MAF_{key}
|
||||
\end{equation}
|
||||
|
||||
With $M_{maf}$ the median of the means of applicable forces, $50 g$ the most
|
||||
With $M_{maf}$ the median of the means of applicable forces, $50\,g$ the most
|
||||
commonly found actuation force on the market (Section \ref{sec:market_forces}),
|
||||
$GFR_{key}$ the gram to force ratio, $MAF_{key}$ the median of applicable force
|
||||
for a specific key and $AF_{key}$ the actuation force for that specific key in
|
||||
@ -175,7 +177,7 @@ key can be seen in Eq. (\ref{eq:force_example}).
|
||||
|
||||
\begin{equation}
|
||||
\label{eq:force_example}
|
||||
AF_{P} = GFR * MAF_{P} = 3.23 \frac{g}{N} * 10.45 N \approx 33.75 g
|
||||
AF_{P} = GFR * MAF_{P} = 3.23 \frac{g}{N} * 10.45\,N \approx 33.75\,g
|
||||
\end{equation}
|
||||
|
||||
We then assigned the each theoretical actuation force to a group that resembles
|
||||
@ -239,7 +241,7 @@ representing the best fit shown in Table \ref{tbl:force_groups}.
|
||||
\begin{tabular}{?l^c^c^c^c^c^c^c}
|
||||
\toprule
|
||||
\rowstyle{\itshape}
|
||||
\textbf{Spring Stiffness:} & 35 g & 40 g & 45 g & 50 g & 55 g & 60 g \\
|
||||
\textbf{Spring Stiffness:} & 35\,g & 40\,g & 45\,g & 50\,g & 55\,g & 60\,g \\
|
||||
\midrule
|
||||
\emph{\textbf{F5:} Key (g)} & \centered{P&(33.75)\\Ü&(34.56)\\+&(34.56)\\-&(35.01)\\↑&(36.27)}& \centered{Ä&(38.37)\\Ö&(39.63)}&&&&&\\
|
||||
\midrule
|
||||
@ -314,14 +316,14 @@ There were no specific eligibility criteria for participants (n=24) of this
|
||||
study beside the ability to type on a keyboard for longer durations and with all
|
||||
ten fingers. The style used to type was explicitly not restricted to schoolbook
|
||||
touch typing to also evaluate possible effects of the adjusted keyboard on
|
||||
untrained typists. All participants recruited were personal contacts. 54\% of
|
||||
untrained typists. All participants recruited were personal contacts. 54\,\% of
|
||||
subjects were females. Participant's ages ranged from 20 to 58 years with a mean
|
||||
age of 29. Sixteen out of the twenty-four subjects (67\%) reported that they
|
||||
age of 29. Sixteen out of the twenty-four subjects (67\,\%) reported that they
|
||||
were touch typists. Subjects reported the following keyboard types as their
|
||||
daily driver, notebook keyboard (12, 50\%), external keyboard (11, 46\%) and
|
||||
split keyboard (1, 4\%). The keyswitch types of those keyboards were distributed
|
||||
as follows: scissor-switch (13, 54\%), rubber dome (8, 33\%) and mechanical
|
||||
keyswitches (3, 13\%). We measured the actuation force of each participants own
|
||||
daily driver, notebook keyboard (12, 50\,\%), external keyboard (11, 46\,\%) and
|
||||
split keyboard (1, 4\,\%). The keyswitch types of those keyboards were distributed
|
||||
as follows: scissor-switch (13, 54\,\%), rubber dome (8, 33\,\%) and mechanical
|
||||
keyswitches (3, 13\,\%). We measured the actuation force of each participants own
|
||||
keyboard and the resulting distribution of actuation forces can be observed in
|
||||
Figure \ref{fig:main_actuation_force}. The self-reported average daily usage of
|
||||
a keyboard ranged from 1 hour to 13 hours, with a mean of 6.69 hours. As already
|
||||
@ -345,7 +347,7 @@ throughout the experiment.
|
||||
The whole experiments took place in a room normally used as an office. Chair,
|
||||
and table were both height adjustable. The armrests of the chair were also
|
||||
adjustable in height and horizontal position. The computer used for all
|
||||
measurements featured an Intel i7-5820K (12) @ 3.600GHz processor, 16 GB RAM and
|
||||
measurements featured an Intel i7-5820K (12) @ 3.600\,GHz processor, 16\,gB RAM and
|
||||
a NVIDIA GeForce GTX 980 Ti graphics card. The operating system on test machine
|
||||
was running \textit{Arch Linux}\footnote{\url{https://archlinux.org/}}
|
||||
(GNU/Linux, Linux kernel version: 5.11.16). The setup utilized two 1080p (Full
|
||||
@ -381,11 +383,11 @@ corresponding actuation force can be found in Table \ref{tbl:kb_pseudo}.
|
||||
\rowstyle{\itshape}
|
||||
Pseudonym & Actuation Force && Description\\
|
||||
\midrule
|
||||
\textbf{Own} & 35 g - 65 g & $\approx$ 0.34 N - 0.64 N & Participant's own keyboard (Figure \ref{fig:main_actuation_force})\\
|
||||
\textbf{Nyx} & 35 g & $\approx$ 0.34 N & Uniform\\
|
||||
\textbf{Aphrodite} & 50 g & $\approx$ 0.49 N & Uniform\\
|
||||
\textbf{Athena} & 80 g & $\approx$ 0.78 N & Uniform\\
|
||||
\textbf{Hera} & 35 g - 60 g & $\approx$ 0.34 N - 0.59 N & Non-uniform / Adjusted (Figure \ref{fig:adjusted_layout})\\
|
||||
\textbf{Own} & 35\,g - 65\,g & $\approx$ 0.34\,N - 0.64\,N & Participant's own keyboard (Figure \ref{fig:main_actuation_force})\\
|
||||
\textbf{Nyx} & 35\,g & $\approx$ 0.34\,N & Uniform\\
|
||||
\textbf{Aphrodite} & 50\,g & $\approx$ 0.49\,N & Uniform\\
|
||||
\textbf{Athena} & 80\,g & $\approx$ 0.78\,N & Uniform\\
|
||||
\textbf{Hera} & 35\,g - 60\,g & $\approx$ 0.34\,N - 0.59\,N & Non-uniform / Adjusted (Figure \ref{fig:adjusted_layout})\\
|
||||
\bottomrule
|
||||
\end{tabular}
|
||||
\caption{Pseudonyms used for the keyboards throughout the experiment.}
|
||||
@ -457,8 +459,8 @@ was then confirmed, by observing the data received by the \textit{FlexVolt
|
||||
the participant performed flexion and extension of the wrist. The
|
||||
\textit{FlexVolt 8-Channel Bluetooth Sensor} used following hardware settings to
|
||||
record the data: 8-Bit sensor resolution, 32ms \gls{RMS} window size and
|
||||
Hardware smoothing filter turned off. To gather reference values (100\%\gls{MVC}
|
||||
and 0\%\gls{MVC}), which are used later to calculate the percentage of muscle
|
||||
Hardware smoothing filter turned off. To gather reference values (100\,\%\gls{MVC}
|
||||
and 0\,\%\gls{MVC}), which are used later to calculate the percentage of muscle
|
||||
activity for each test, we performed three measurements. First, participants
|
||||
were instructed to fully relax the \gls{FDS}, \gls{FDP} and \gls{ED} by
|
||||
completely resting their forearms on the table. Second, participants exerted
|
||||
@ -466,8 +468,8 @@ maximum possible force with their fingers (volar) against the top of the table
|
||||
(\gls{MVC} - flexion) and lastly, participants applied maximum possible force
|
||||
with their fingers (dorsal) to the bottom of the table while resting their
|
||||
forearms on their thighs (\gls{MVC} - extension). We decided to also measure
|
||||
0\%\gls{MVC} before and after each typing test and used these values to
|
||||
normalize the final data instead of the 0\%\gls{MVC} we retrieved from the
|
||||
0\,\%\gls{MVC} before and after each typing test and used these values to
|
||||
normalize the final data instead of the 0\,\%\gls{MVC} we retrieved from the
|
||||
initial \gls{MVC} measurements. A picture of all participants with the attached
|
||||
electrodes can be observed in Appendix \ref{app:emg}.
|
||||
|
||||
@ -477,13 +479,13 @@ Participants could familiarize themselves with the typing test application
|
||||
(\gls{GoTT}) for up to five minutes with a keyboard that was not used during the
|
||||
experiment. Further, representative of the other keyboard models used in the
|
||||
experiment (\gls{GMMK}), participants could familiarize themselves with
|
||||
Aphrodite (50 g). Additionally, because of a possible height difference between
|
||||
Aphrodite (50\,g). Additionally, because of a possible height difference between
|
||||
\gls{GMMK} compared to notebook or other keyboards, participants were given the
|
||||
choice to use wrist rests of adequate height in combination with all four
|
||||
keyboards during the experiment. If during this process participants reported
|
||||
that an electrode is uncomfortable and that it would influence the following
|
||||
typing test, this electrode was relocated and the procedure in the last section
|
||||
was repeated (Happened one time during the whole experiment).
|
||||
was repeated\footnote{Happened one time during the whole experiment}.
|
||||
|
||||
\textbf{Texts Used for Typing Tests}
|
||||
|
||||
@ -508,7 +510,7 @@ the limited time participants had to fill out the questionnaires in between
|
||||
typing tests (2 - 3 minutes) and also because participants had to rate multiple
|
||||
keyboards in one session \cite{schrepp_ueq_handbook}.
|
||||
|
||||
\textbf{Post Experiment Interview \& UX-Curves}
|
||||
\textbf{Post Experiment Interview \& \Gls{UX Curve}s}
|
||||
|
||||
To give participants the chance to recapitulate their experience during the
|
||||
whole experiment, we conducted a semi-structured interview, after all typing
|
||||
@ -517,11 +519,11 @@ interviews and afterwards categorized common statements about each
|
||||
keyboard.
|
||||
|
||||
Further, we prepared two different graphs were participants had to draw
|
||||
UX-Curves related to subjectively perceived typing speed and subjectively
|
||||
\Gls{UX Curve}s related to subjectively perceived typing speed and subjectively
|
||||
perceived fatigue for every keyboard and corresponding typing test. The graphs
|
||||
always reflected the order of keyboards for the group the current participant
|
||||
was part of. Furthermore, before the interview started, participants were given
|
||||
a brief introduction on how to draw UX-Curves and that it is desirable to
|
||||
a brief introduction on how to draw \Gls{UX Curve}s and that it is desirable to
|
||||
explain the thought process while drawing each curve \cite{kujala_ux_curve}. An
|
||||
example of the empty graph for perceived fatigue (group 1) can be seen in Figure
|
||||
\ref{fig:empty_ux_g1}.
|
||||
@ -529,7 +531,7 @@ example of the empty graph for perceived fatigue (group 1) can be seen in Figure
|
||||
\begin{figure}[H]
|
||||
\centering
|
||||
\includegraphics[width=1.0\textwidth]{images/empty_ux_g1}
|
||||
\caption{Empty graph for participants of group 1 to draw an UX-curve related
|
||||
\caption{Empty graph for participants of group 1 to draw an \gls{UX Curve} related
|
||||
to perceived fatigue during the experiment}
|
||||
\label{fig:empty_ux_g1}
|
||||
\end{figure}
|
||||
@ -538,8 +540,8 @@ example of the empty graph for perceived fatigue (group 1) can be seen in Figure
|
||||
|
||||
Each subject had to take two, 5 minute, typing tests per keyboard, with a total
|
||||
of 5 keyboards, namely \textit{Own (participant's own keyboard)}, \textit{Nyx
|
||||
(35 g, uniform), Aphrodite (50 g, uniform), Athena (80 g uniform)} and
|
||||
\textit{Hera (35 g - 60 g, adjusted)} (Table \ref{tbl:kb_pseudo}). As described
|
||||
(35\,g, uniform), Aphrodite (50\,g, uniform), Athena (80\,g uniform)} and
|
||||
\textit{Hera (35\,g - 60\,g, adjusted)} (Table \ref{tbl:kb_pseudo}). As described
|
||||
in Section \ref{sec:main_keyboards}, the order of the keyboards \textit{Nyx,
|
||||
Aphrodite, Athena} and \textit{Hera} was counterbalanced with the help of a
|
||||
balanced latin square to reduce order effects. The keyboard \textit{Own} was
|
||||
@ -566,4 +568,4 @@ necessary data for the design of the adjusted keyboard layout. Throughout the
|
||||
main user study, where we compared five different keyboards, we were able to
|
||||
obtain various qualitative and quantitative data regarding performance and
|
||||
satisfaction. The statistical evaluation of this data will be presented in the
|
||||
next Section.
|
||||
next sections.
|
||||
|
||||
@ -15,7 +15,7 @@ tests \cite{field_stats, downey_stats}. The reliability of the two sub-scales
|
||||
(hedonic and pragmatic quality) in the \glsfirst{UEQ-S} was estimated using
|
||||
\textit{Cronbach's alpha} \cite{tavakol_cronbachs_alpha}. All results are
|
||||
reported statistically significant with an $\alpha$-level of $p < 0.05$. We used
|
||||
95\% confidence intervals when presenting certain results. Normality of data or
|
||||
95\,\% confidence intervals when presenting certain results. Normality of data or
|
||||
residuals was checked using visual assessment of \gls{Q-Q} plots and
|
||||
additionally \textit{Shapiro-Wilk} Test. Further, we used \textit{Mauchly's Test
|
||||
for Sphericity} to evaluate if there was statistically significant variation
|
||||
@ -95,13 +95,13 @@ can be observed in Table \ref{tbl:res_own_before_after}.
|
||||
We also evaluated the means of \glsfirst{KCQ} questions 8 to 12 which concerned
|
||||
perceived fatigue in fingers, wrists, arms, shoulders and neck respectively
|
||||
(7-point Likert scale) and the slopes (improving, deteriorating, stable) of the
|
||||
UX-curves drawn by each participant after the whole experiment, to identify
|
||||
\gls{UX Curve}s drawn by each participant after the whole experiment, to identify
|
||||
possible differences in perceived fatigue from T0\_1 to T0\_2. As shown in
|
||||
Figure \ref{fig:res_own_per_fat}, participants \gls{KCQ} reported slight
|
||||
improvements in terms of finger (diff = 0.33) and wrist (diff = 0.33) fatigue in
|
||||
T0\_2 compared to T0\_1, no difference in arm fatigue (diff = 0) and very
|
||||
slightly increased fatigue in shoulder (diff = -0.12) and neck (diff = -0.13) in
|
||||
T0\_2 compared to T0\_1. Sixteen of the twenty-four UX-curves regarding overall
|
||||
T0\_2 compared to T0\_1. Sixteen of the twenty-four \gls{UX Curve}s regarding overall
|
||||
perceived fatigue had positive slope when measured from start of T0\_1 to end of
|
||||
T0\_2 ($\pm$ 1 mm). The subjective reports about the decrease in finger and
|
||||
wrist fatigue emphasize the decrease in muscle activity for the flexor muscles
|
||||
@ -112,7 +112,7 @@ we described in the last paragraph.
|
||||
\includegraphics[width=1.0\textwidth]{images/res_own_per_fat}
|
||||
\caption{Trends for reported fatigue through the \gls{KCQ} (questions 8:
|
||||
finger, 9: wrist, 10: arm, 11: shoulder, 12: neck) and histogram for the
|
||||
slopes (IM: improving, DE: deteriorating, ST: stable) of UX-curves
|
||||
slopes (IM: improving, DE: deteriorating, ST: stable) of \gls{UX Curve}s
|
||||
concerning perceived fatigue. The curves were evaluated by looking at the y
|
||||
value of the starting point for T0\_1 and comparing it to y value of the end
|
||||
point for T0\_2 with a margin of $\pm$ 1 mm}
|
||||
@ -144,12 +144,12 @@ relevant results of the post-hoc tests and the summary of the performance data
|
||||
can be observed in Tables \ref{tbl:sum_tkbs_speed} and
|
||||
\ref{tbl:res_tkbs_speed}. We further examined, which of the four test keyboard
|
||||
was the fastest for each participant and found, that \textit{Hera} was the
|
||||
fastest keyboard in terms of \gls{WPM} for 46\% (11) of the twenty-four
|
||||
fastest keyboard in terms of \gls{WPM} for 46\,\% (11) of the twenty-four
|
||||
subjects. Additionally, we analyzed the \gls{WPM} percentage of \textit{Own}
|
||||
(\gls{OPC}) for all test keyboards to figure out, which keyboard exceeded the
|
||||
performance of the participant's own keyboard. We found, that three subjects
|
||||
reached \gls{OPC}\_\gls{WPM} values greater than 100\% with all four test
|
||||
keyboards. Also, \textit{Athena, Aphrodite} and \textit{Hera} exceeded 100\% of
|
||||
reached \gls{OPC}\_\gls{WPM} values greater than 100\,\% with all four test
|
||||
keyboards. Also, \textit{Athena, Aphrodite} and \textit{Hera} exceeded 100\,\% of
|
||||
\gls{OPC}\_\gls{WPM} eight, seven and six times respectively. Detailed results
|
||||
are presented in Figure \ref{fig:max_opc_wpm}.
|
||||
|
||||
@ -230,7 +230,7 @@ are presented in Figure \ref{fig:max_opc_wpm}.
|
||||
\includegraphics[width=1.0\textwidth]{images/max_opc_wpm}
|
||||
\caption{The left graph shows the fastest keyboard in terms of \gls{WPM} for
|
||||
each participant. The right graph shows, which keyboards were even faster
|
||||
than the participant's own keyboard (\gls{OPC}\_\gls{WPM} > 100\%)}
|
||||
than the participant's own keyboard (\gls{OPC}\_\gls{WPM} > 100\,\%)}
|
||||
\label{fig:max_opc_wpm}
|
||||
\end{figure}
|
||||
|
||||
@ -247,7 +247,7 @@ conduct the analysis. The Friedman's Tests for \gls{TER} ($\chi^2$(3) = 25.4, p
|
||||
(\gls{GG})) revealed differences for at least two test keyboards. The Friedman's
|
||||
Test for \gls{UER} ($\chi^2$(3) = 2.59, p = 0.46) yielded no statistical
|
||||
significant difference. It should be noted, that the 90th percentile of
|
||||
\gls{UER} for all keyboards was still below 1\%. Summaries for the individual
|
||||
\gls{UER} for all keyboards was still below 1\,\%. Summaries for the individual
|
||||
metrics and results for all post-hoc tests can be seen in Table
|
||||
\ref{tbl:sum_tkbs_err} and \ref{tbl:res_tkbs_err}. Furthermore, we compared the
|
||||
\gls{TER} of all test keyboards for each participant and found, that
|
||||
@ -341,7 +341,7 @@ to \textit{Own} (\gls{OPC}). All data can be observed in Figure
|
||||
\includegraphics[width=1.0\textwidth]{images/max_opc_ter}
|
||||
\caption{The left graph shows the keyboard with the lowest \gls{TER} for each
|
||||
participant. The right graph shows, which keyboards were more accurate than
|
||||
the participant's own keyboard (\gls{OPC}\_\gls{TER} < 100\%)}
|
||||
the participant's own keyboard (\gls{OPC}\_\gls{TER} < 100\,\%)}
|
||||
\label{fig:max_opc_ter}
|
||||
\end{figure}
|
||||
|
||||
@ -366,11 +366,11 @@ test keyboards of the mean values for both typing tests combined can be observed
|
||||
in Table \ref{tbl:sum_tkbs_emg}. Lastly, we created histograms (Figure
|
||||
\ref{fig:max_emg_tkbs}) for each of the observed muscle groups, that show the
|
||||
number of times a keyboard yielded the highest \%\gls{MVC} out of all keyboards
|
||||
for each participant. We found, that \textit{Athena} most frequently ($\approx$45\%)
|
||||
for each participant. We found, that \textit{Athena} most frequently ($\approx$45\,\%)
|
||||
produced the highest extensor muscle activity for both arms. The highest muscle
|
||||
activity for both flexor muscle groups was evenly distributed among all test
|
||||
keyboards with a slight exception of \textit{Nyx}, which produced the highest
|
||||
\%\gls{MVC} only in ~14\% of participants.
|
||||
\%\gls{MVC} only in ~14\,\% of participants.
|
||||
|
||||
\begin{figure}[H]
|
||||
\centering
|
||||
@ -518,7 +518,7 @@ Table \ref{tbl:res_kcq}.
|
||||
\end{table}
|
||||
\subsubsection{User Experience Questionnaire (Short)}
|
||||
\label{sec:res_ueqs}
|
||||
Additionally to the \gls{KCQ} we utilized the \glsfirst{UEQ-S}. It featured
|
||||
In addition to to the \gls{KCQ}, we utilized the \glsfirst{UEQ-S}. It featured
|
||||
eight questions on a 7-point Likert scale, which formed two scales (pragmatic,
|
||||
hedonic). Additionally we added one extra question that could be answered on a
|
||||
\glsfirst{VAS} from 0 to 100. The survey was filled out after both tests with a
|
||||
@ -596,7 +596,7 @@ observed in Tables \ref{tbl:res_tkbs_sati} and \ref{tbl:sum_tkbs_sati}.
|
||||
towards significance are denoted with $\dagger$. Confidence intervals are
|
||||
given for the difference of the location parameter. We only tested keyboards
|
||||
with lower actuation force against keyboards with higher actuation
|
||||
force. The first comparison of Aphrodite (50 g) and Nyx (35 g) was added,
|
||||
force. The first comparison of Aphrodite (50\,g) and Nyx (35\,g) was added,
|
||||
because of the noticeable differences in the visual assessment of Figure
|
||||
\ref{fig:res_tkbs_sati}}
|
||||
\label{tbl:res_tkbs_sati}
|
||||
@ -637,7 +637,7 @@ observed in Tables \ref{tbl:res_tkbs_sati} and \ref{tbl:sum_tkbs_sati}.
|
||||
\label{sec:res_uxc}
|
||||
In order to give all participants the chance to recapitulate the whole
|
||||
experiment and give retrospective feedback about each individual keyboard, we
|
||||
conducted a semi-structured interview which included drawing UX-curves for
|
||||
conducted a semi-structured interview which included drawing \gls{UX Curve}s for
|
||||
perceived fatigue and perceived typing speed. We evaluated the curves by
|
||||
measuring the y position of the \gls{SP} for a curve and the y position of the
|
||||
respective \gls{EP} an determine the slope of that curve. Slopes are defined as
|
||||
@ -655,7 +655,7 @@ participants own keyboard was four times more often placed first than any other
|
||||
keyboard. \textit{Hera} was the only keyboard, that never got placed fifth and
|
||||
except for \textit{Own}, was the most represented keyboard in the top three. The
|
||||
ranking of the perceived actuation force revealed, that participants were able
|
||||
to identify \textit{Nyx} (35 g) and \textit{Athena} (80 g) as the keyboards with
|
||||
to identify \textit{Nyx} (35\,g) and \textit{Athena} (80\,g) as the keyboards with
|
||||
the lowest and highest actuation force respectively. All results for both
|
||||
rankings are visualized in Figure \ref{fig:res_interview}. Lastly, we analyzed
|
||||
the recordings of all interviews and found several similar statements about
|
||||
@ -674,7 +674,7 @@ which could be related to a comment of two subjects―\textit{``It felt very
|
||||
\begin{figure}[H]
|
||||
\centering
|
||||
\includegraphics[width=1.0\textwidth]{images/res_uxc}
|
||||
\caption{\centering Evaluation of UX-curve slopes for perceived fatigue and perceived
|
||||
\caption{\centering Evaluation of \gls{UX Curve} slopes for perceived fatigue and perceived
|
||||
speed. \\
|
||||
\textit{DE:} deteriorating, \textit{IM:} improving, \textit{ST:} stable}
|
||||
\label{fig:res_uxc}
|
||||
|
||||
@ -12,19 +12,19 @@ question \textit{``Does an adjusted actuation force per key have a positive
|
||||
Our main experiment yielded, that there are differences in typing speed for both
|
||||
metrics related to transcribed text we measured―namely \glsfirst{WPM} and
|
||||
\glsfirst{AdjWPM}. Especially the keyboard with the lowest uniform actuation
|
||||
force of 35 g―\textit{Nyx}―performed worse than all other keyboards. In terms of
|
||||
\gls{WPM}, \textit{Nyx (35 g)} was on average 4.1\% slower than \textit{Athena
|
||||
(80 g)} and \textit{Aphrodite (50 g)} and 4.8\% slower than the adjusted
|
||||
keyboard \textit{Hera (35 - 60 g)}. Similarly, for \gls{AdjWPM}, \textit{Nyx}
|
||||
was 4.3\% slower than \textit{Athena} and \textit{Aphrodite} and 4.9\% slower
|
||||
than \textit{Hera}. The 4\% to 5\% difference in \gls{WPM} and \gls{AdjWPM} in
|
||||
our sample account for approximately 2 words per minute. When extrapolated with
|
||||
the mean daily keyboard usage of 6.69 hours reported by our participants, this
|
||||
difference would be as big as 803 words, which when put into perspective, is
|
||||
equivalent to roughly two full pages of only written content (11pt font
|
||||
size). Although, this specific example would assume constant typing for 6.69
|
||||
hours, it is still a useful estimate of the loss in productivity under normal
|
||||
working conditions over the course of several days. These differences in
|
||||
force of 35\,g―\textit{Nyx}―performed worse than all other keyboards. In terms
|
||||
of \gls{WPM}, \textit{Nyx (35\,g)} was on average 4.1\,\% slower than
|
||||
\textit{Athena (80\,g)} and \textit{Aphrodite (50\,g)} and 4.8\,\% slower than the
|
||||
adjusted keyboard \textit{Hera (35 - 60\,g)}. Similarly, for \gls{AdjWPM},
|
||||
\textit{Nyx} was 4.3\,\% slower than \textit{Athena} and \textit{Aphrodite} and
|
||||
4.9\,\% slower than \textit{Hera}. The 4\,\% to 5\,\% difference in \gls{WPM} and
|
||||
\gls{AdjWPM} in our sample account for approximately 2 words per minute. When
|
||||
extrapolated with the mean daily keyboard usage of 6.69 hours reported by our
|
||||
participants, this difference would be as big as 803 words, which when put into
|
||||
perspective, is equivalent to roughly two full pages of only written content
|
||||
(11pt font size). Although, this specific example would assume constant typing
|
||||
for 6.69 hours, it is still a useful estimate of the loss in productivity under
|
||||
normal working conditions over the course of several days. These differences in
|
||||
\gls{WPM} and \gls{AdjWPM} could be explained by the higher error rates and
|
||||
thereby the loss of ``typing flow'' we discuss in the next section. \gls{KSPS}
|
||||
reflects the raw input speed by including backspaces and previously deleted
|
||||
@ -32,10 +32,10 @@ characters. The reason we included \gls{KSPS} in our analysis was to reveal
|
||||
possible differences in the physical speed participants type on a keyboard and
|
||||
not to further asses speed in the sense of productivity. We could not find any
|
||||
statistically significant differences in \gls{KSPS} but saw a trend, indicating
|
||||
that subjects typed a bit slower (< 3\%) on \textit{Athena (80 g)} compared to
|
||||
\textit{Aphrodite (50 g)} and \textit{Hera (35 - 60 g)}. With the differences in
|
||||
metrics that are commonly used to measure typing speed more closely related to
|
||||
productivity (\gls{WPM}, \gls{AdjWPM}) and the trends that indicate a slight
|
||||
that subjects typed a bit slower (< 3\,\%) on \textit{Athena (80\,g)} compared to
|
||||
\textit{Aphrodite (50\,g)} and \textit{Hera (35 - 60\,g)}. With the differences
|
||||
in metrics that are commonly used to measure typing speed more closely related
|
||||
to productivity (\gls{WPM}, \gls{AdjWPM}) and the trends that indicate a slight
|
||||
difference in operating speed we could have accepted our hypothesis. However,
|
||||
with the relation between error rate and typing speed described in the next
|
||||
section and the thereby rather indirect effect of the actuation force, we can
|
||||
@ -46,7 +46,7 @@ force, has an impact on typing speed.
|
||||
Actuation force has an impact on typing speed (efficiency - speed).
|
||||
\end{phga_hyp*}
|
||||
|
||||
% During our telephone interviews 76\% of respondents would have preferred a
|
||||
% During our telephone interviews 76\,\% of respondents would have preferred a
|
||||
% keyboard with lighter actuation force.
|
||||
|
||||
% Our study tried to present the participant with a typing scenario that is as
|
||||
@ -58,16 +58,16 @@ force, has an impact on typing speed.
|
||||
|
||||
As already briefly mentioned in Section \ref{sec:dis_speed}, measured error
|
||||
rates like \glsfirst{UER}, \glsfirst{CER} and \glsfirst{TER} differed especially
|
||||
between \textit{Nyx (35 g)} and the other test keyboards. The statistical
|
||||
between \textit{Nyx (35\,g)} and the other test keyboards. The statistical
|
||||
analyses further revealed, that \textit{Athena}, the keyboard with the highest
|
||||
actuation force of 80 g, produced on average 1\% less \gls{TER} than
|
||||
\textit{Hera (35 - 60 g)} and \textit{Aphrodite (50 g)} and 3\% less than
|
||||
\textit{Nyx (35g)}. Furthermore, \textit{Hera} and \textit{Aphrodite} both had a
|
||||
2\% lower \gls{TER} than \textit{Nyx}. Additionally to the quantitative results,
|
||||
actuation force of 80\,g, produced on average 1\,\% less \gls{TER} than
|
||||
\textit{Hera (35 - 60\,g)} and \textit{Aphrodite (50\,g)} and 3\,\% less than
|
||||
\textit{Nyx (35\,g)}. Furthermore, \textit{Hera} and \textit{Aphrodite} both had a
|
||||
2\,\% lower \gls{TER} than \textit{Nyx}. Additionally to the quantitative results,
|
||||
fourteen of the twenty-four participants also reported, that \textit{Nyx's}
|
||||
light actuation force was the reason for many accidental key presses. It further
|
||||
stood out, that as shown in Figure \ref{fig:max_opc_ter}, \textit{Athena} was
|
||||
the most accurate keyboard for 58\% of participants and also more accurate than
|
||||
the most accurate keyboard for 58\,\% of participants and also more accurate than
|
||||
keyboard \textit{Own} for eleven of the subjects. Overall, this concludes, that
|
||||
a higher actuation force has a positive impact on error rate.
|
||||
|
||||
@ -131,7 +131,7 @@ significant differences for any of the test keyboards regarding the pragmatic
|
||||
scale of the \gls{UEQ-S}. From visual assessment of the graph shown in Figure
|
||||
\ref{fig:ueq_tkbs_res} we could conclude, that there is a slight trend towards a
|
||||
more positive rating for keyboards that utilized keyswitches with higher
|
||||
actuation forces than \textit{Nyx (35 g)}. This trend in the opposite direction
|
||||
actuation forces than \textit{Nyx (35\,g)}. This trend in the opposite direction
|
||||
of our hypothesized outcome, that lighter actuation force leads to more user
|
||||
satisfaction, could be due to the longer familiarization time required for
|
||||
keyboards with very light actuation force \cite{gerard_keyswitch}.
|
||||
@ -141,10 +141,10 @@ keyboards with very light actuation force \cite{gerard_keyswitch}.
|
||||
The results deduced from the additional question \textit{``How satisfied have
|
||||
you been with this keyboard?''}, which could be answered on a \glsfirst{VAS}
|
||||
from 0 to 100 after both tying tests with a keyboard, suggested that \textit{Nyx
|
||||
(35 g)}, the keyboard with the lightest actuation force and also
|
||||
\textit{Athena (80 g)} the keyboard with the highest actuation force, were rated
|
||||
significantly worse than \textit{Aphrodite (50 g)}. Additionally, \textit{Hera
|
||||
(35 - 60 g)}, the adjusted keyboard showed a trend towards a significantly
|
||||
(35\,g)}, the keyboard with the lightest actuation force and also
|
||||
\textit{Athena (80\,g)} the keyboard with the highest actuation force, were rated
|
||||
significantly worse than \textit{Aphrodite (50\,g)}. Additionally, \textit{Hera
|
||||
(35 - 60\,g)}, the adjusted keyboard showed a trend towards a significantly
|
||||
better rating than \textit{Nyx}. These results indicate, that neither of the
|
||||
keyboards with extreme actuation forces were perceived as a overwhelmingly
|
||||
pleasant keyboard to use during our typing tests. This is further supported by
|
||||
@ -156,15 +156,15 @@ the average ratings for \textit{Aphrodite} and \textit{Hera} were approximately
|
||||
|
||||
For the \gls{KCQ} we found several statistically significant differences. For
|
||||
questions related to effort or fatigue while operating a keyboard,
|
||||
\textit{Athena (80 g)} received significantly lower ratings than the other test
|
||||
\textit{Athena (80\,g)} received significantly lower ratings than the other test
|
||||
keyboards. Additionally to the measured differences in error rates discussed in
|
||||
Section \ref{sec:dis_error}, we discovered that participants also perceived the
|
||||
accuracy of \textit{Athena (80 g)} and \textit{Aphrodite (50 g)} higher compared
|
||||
to \textit{Nyx (35 g)}. Similarly to the results discussed in the last
|
||||
accuracy of \textit{Athena (80\,g)} and \textit{Aphrodite (50\,g)} higher compared
|
||||
to \textit{Nyx (35\,g)}. Similarly to the results discussed in the last
|
||||
paragraph, the scores of the two keyboards with extreme actuation forces,
|
||||
\textit{Nyx (35 g)} and \textit{Athena (80 g)} fluctuated quite a bit and on
|
||||
average those two keyboards scored lower than \textit{Aphrodite (50 g)} or
|
||||
\textit{Hera (35 - 60 g)} (Figure \ref{fig:kcq_tkbs_res}). Thereby, these
|
||||
\textit{Nyx (35\,g)} and \textit{Athena (80\,g)} fluctuated quite a bit and on
|
||||
average those two keyboards scored lower than \textit{Aphrodite (50\,g)} or
|
||||
\textit{Hera (35 - 60\,g)} (Figure \ref{fig:kcq_tkbs_res}). Thereby, these
|
||||
results do not indicate a clear trend towards enhanced user experience when
|
||||
using keyboards with lower actuation forces.
|
||||
|
||||
@ -194,7 +194,7 @@ Figure \ref{fig:ratio_interview}, to evaluate preferences towards specific
|
||||
keyboards, that could not be expressed by our participants through any other
|
||||
supplied method during the experiment. Like all other factors we identified as
|
||||
reasonable indicators for satisfaction, these ratios yielded, that neither
|
||||
\textit{Athena (80 g)} nor \textit{Nyx (35 g)} received more positive than
|
||||
\textit{Athena (80\,g)} nor \textit{Nyx (35\,g)} received more positive than
|
||||
negative feedback. It should be noted, that previous research has shown that
|
||||
people tend to remember and process bad experiences more thorough than good
|
||||
ones, which could be a reason for the increased number of negative feedback for
|
||||
@ -211,13 +211,13 @@ those two keyboards \cite{baumeister_bad}.
|
||||
|
||||
\textbf{Conclusion}
|
||||
|
||||
Contrary to the responses of our preliminary telephone interview, where 76\% of
|
||||
Contrary to the responses of our preliminary telephone interview, where 76\,\% of
|
||||
attendees preferred a keyboard with light actuation force, none of the factors
|
||||
we defined as relevant for user satisfaction suggests, that keyboards with lower
|
||||
actuation force are more satisfactory to use than keyboards with higher
|
||||
actuation force. Therefore, we have to fully reject our hypothesis. We can
|
||||
conclude thought, that keyboards with actuation forces in between those two
|
||||
extremes (35 g / 80 g), are persistently perceived as more pleasant to use and
|
||||
extremes (35\,g / 80\,g), are persistently perceived as more pleasant to use and
|
||||
that ratings keyboards with extreme actuation forces are highly influenced by
|
||||
personal preference, which is indicated by the high fluctuation of almost all
|
||||
responses regarding our evaluated factors.
|
||||
@ -232,7 +232,7 @@ responses regarding our evaluated factors.
|
||||
In contrast to other studies that suggested, that actuation force has an impact
|
||||
on muscle activity, we could not identify significant differences in terms of \%
|
||||
of \glsfirst{MVC} for any of our \gls{EMG} measurements. Only a slight trend,
|
||||
that \textit{Nyx (35 g)} produced the highest flexor \%\gls{MVC} for only 14\%
|
||||
that \textit{Nyx (35\,g)} produced the highest flexor \%\gls{MVC} for only 14\,\%
|
||||
of participants, could be interpreted as anecdotal evidence towards our
|
||||
hypothesis, that actuation force has an impact on muscle activity. Therefore we
|
||||
have to reject our hypothesis.
|
||||
@ -256,7 +256,7 @@ perceived as equivalent to the participant's own keyboard. In fact,
|
||||
\textit{Hera} was the keyboard with the most occurrences in the top three, tied
|
||||
first place with \textit{Aphrodite} and was never ranked 4th place during the
|
||||
post-experiment interview (Figure \ref{fig:tkbs_ranking}). Since \textit{Hera},
|
||||
among others, utilized keyswitches with light actuation force (35 g), the
|
||||
among others, utilized keyswitches with light actuation force (35\,g), the
|
||||
satisfaction could improve during prolonged usage, because of the longer
|
||||
familiarization period required by keyboards with lighter actuation forces
|
||||
\cite{gerard_keyswitch}. Interestingly, participant \textit{I3Z4XI7H} who
|
||||
@ -274,16 +274,16 @@ that an adjusted keyboard is more satisfactory to use than standard keyboards.
|
||||
to standard keyboards.
|
||||
\end{phga_hyp*}
|
||||
|
||||
Similarly, the resulting error rates measured for \textit{Hera (35 - 60 g)} were
|
||||
close to equal to the results of \textit{Aphrodite (50 g)} and for speed related
|
||||
Similarly, the resulting error rates measured for \textit{Hera (35 - 60\,g)} were
|
||||
close to equal to the results of \textit{Aphrodite (50\,g)} and for speed related
|
||||
metrics between those two keyboards only slight improvements while using
|
||||
\textit{Hera} in \gls{WPM} (0.8\%), \gls{AdjWPM} (0.6\%) and \gls{KSPS} (1\%)―
|
||||
\textit{Hera} in \gls{WPM} (0.8\,\%), \gls{AdjWPM} (0.6\,\%) and \gls{KSPS} (1\,\%)―
|
||||
that were not statistically significant―were recorded during our experiment. It
|
||||
was still interesting to see, that \textit{Hera} was the fastest, out of all
|
||||
four test keyboards, for eleven (45\%) out of the twenty-four subjects and that
|
||||
albeit the usage of 30\% keyswitches\footnote{That were actually pressed during
|
||||
our typing tests} that required 35 - 40 g actuation force, which is similar to
|
||||
the actuation force of \textit{Nyx (35 g)}, we did not see comparably high error
|
||||
four test keyboards, for eleven (45\,\%) out of the twenty-four subjects and that
|
||||
albeit the usage of 30\,\% keyswitches\footnote{That were actually pressed during
|
||||
our typing tests} that required 35 - 40\,g actuation force, which is similar to
|
||||
the actuation force of \textit{Nyx (35\,g)}, we did not see comparably high error
|
||||
rates. Because of the lacking evidence, that an adjusted keyboard produces less
|
||||
errors or supports the typist in achieving higher typing speeds, we have to
|
||||
reject our two hypotheses regarding those improvements.
|
||||
@ -299,7 +299,7 @@ reject our two hypotheses regarding those improvements.
|
||||
\end{phga_hyp*}
|
||||
|
||||
Our experiment basically revealed, that keyboards which utilized keyswitches
|
||||
with actuation forces that were neither to light (35 g) nor to heavy (80 g),
|
||||
with actuation forces that were neither too light (35\,g) nor too heavy (80\,g),
|
||||
generally outperformed keyboards which featured those extreme actuation
|
||||
forces. In the following section, we elaborate on possible limitations of our
|
||||
experimental design and future research that could be reasonable to further
|
||||
|
||||
@ -13,7 +13,7 @@ on typing speed, error rate and satisfaction revealed, that higher actuation
|
||||
forces reduce error rates compared to lower actuation forces and that the typing
|
||||
speed is also influenced, \textbf{at least indirectly}, by differences in
|
||||
actuation force. Especially the keyboard with very low actuation force,
|
||||
\textit{Nyx (35 g)}, which also had the highest average error rate was
|
||||
\textit{Nyx (35\,g)}, which also had the highest average error rate was
|
||||
significantly slower than all other keyboards. Therefore, we investigated, if
|
||||
there is a connection between high error rates and stagnating typing speed and
|
||||
found, that in general, the error rate was a factor for lower input
|
||||
@ -21,16 +21,16 @@ rates. Neither the satisfaction nor the muscle activity was significantly
|
||||
influenced solely by the actuation.
|
||||
|
||||
In conclusion, our study showed, that the keyboard with non-uniform actuation
|
||||
forces―\textit{Hera (35 - 60 g)}―was not able to improve the overall typing
|
||||
forces―\textit{Hera (35 - 60\,g)}―was not able to improve the overall typing
|
||||
experience significantly enough to supersede existing designs, but was still a
|
||||
viable alternative to all traditional keyboards we tested. It could be possible,
|
||||
that due to the unconventional force distribution, that similar to keyboards
|
||||
that due to the unconventional force distribution, that is similar to keyboards
|
||||
with very light actuation force, the muscle activity while using \textit{Hera}
|
||||
could decrease when users are given more time to adapt to this keyboard
|
||||
\cite{gerard_keyswitch}. Additionally, we found that keyboards with either very
|
||||
high (80 g) or very low (35 g) actuation forces had the most influence on typing
|
||||
high (80\,g) or very low (35\,g) actuation forces had the most influence on typing
|
||||
related metrics, when compared to the more commonly sold keyboards with around
|
||||
50 g to 60 g actuation force. In the next sections we identify possible
|
||||
50\,g to 60\,g actuation force. In the next sections we identify possible
|
||||
limitations and propose some ideas on how to reevaluate custom keyboard designs
|
||||
in future studies.
|
||||
|
||||
@ -45,7 +45,7 @@ the researcher was in the same room, the limited time for the individual typing
|
||||
tests and the rather short breaks in between typing tests, could have influenced
|
||||
some subjects by inducing unnecessary stress. Another limitation related to the
|
||||
preliminary finger strength study, was the very small number of participants (n
|
||||
= 6). Although we measured the finger strengths in different positions for 50\%
|
||||
= 6). Although we measured the finger strengths in different positions for 50\,\%
|
||||
female and male participants, the age distribution was not diverse (M = 24) and
|
||||
with a higher number of subjects, the results would have been much more
|
||||
reliable. Similarly, the number and diversity in occupation of participants
|
||||
@ -62,8 +62,8 @@ We propose, that in further research related to keyboards with non-uniform
|
||||
actuation force (adjusted keyboards), participants should test several different
|
||||
adjusted keyboards and the results should be compared to one identical looking
|
||||
keyboard that utilizes a uniform layout of keyswitches with an actuation force
|
||||
of 50 g to 65 g. Further, different adjusted layouts, with e.g. higher or lower
|
||||
base actuation force than 50 g could be used to calculate the individual spring
|
||||
of 50\,g to 65\,g. Further, different adjusted layouts, with e.g. higher or lower
|
||||
base actuation force than 50\,g could be used to calculate the individual spring
|
||||
resistances used for each key or a similar layout to the one used in
|
||||
Realforce\footnote{\url{https://www.realforce.co.jp/en/products/}} keyboards,
|
||||
could be compared to each other. Furthermore, long term studies with adjusted
|
||||
|
||||
30
glossary.tex
30
glossary.tex
@ -5,9 +5,11 @@
|
||||
\newacronym{MVC}{MVC}{maximum voluntary contraction}
|
||||
\newacronym{CTS}{CTS}{Carpal Tunnel Syndrome}
|
||||
\newacronym{RSI}{RSI}{Repetitive Strain Injury}
|
||||
\newacronym{TNS}{TNS}{Tension Neck Syndrome}
|
||||
\newacronym{FRE}{FRE}{Flesch Reading Ease Score}
|
||||
\newacronym{VAS}{VAS}{visual analog scale}
|
||||
\newacronym{RMS}{RMS}{root-mean-square}
|
||||
\newacronym{ISO}{ISO}{International Organization for Standardization}
|
||||
% Mulcles alive p. 189
|
||||
% Atlas of Human Anatomy p. 433
|
||||
\newacronym{FDS}{FDS}{flexor digitorum superficialis}
|
||||
@ -45,25 +47,22 @@
|
||||
\newacronym{EP}{EP}{end point}
|
||||
\newacronym{LRT}{LRT}{Likelihood Ratio Test}
|
||||
|
||||
|
||||
|
||||
|
||||
\newglossaryentry{N}{
|
||||
name={N},
|
||||
description={Newton: 1 N $ \approx $ 101.97 g}
|
||||
description={Newton: 1\,N $ \approx $ 101.97\,g}
|
||||
}
|
||||
|
||||
\newglossaryentry{cN}{
|
||||
name={cN},
|
||||
description={Centinewton: 1 cN $ \approx $ 1.02 g}
|
||||
description={Centinewton: 1\,cN $ \approx $ 1.02\,g}
|
||||
}
|
||||
\newglossaryentry{g}{
|
||||
name={g},
|
||||
description={Gram: 1 g $ \approx $ 0.97 cN}
|
||||
description={Gram: 1\,g $ \approx $ 0.97\,cN}
|
||||
}
|
||||
\newglossaryentry{gf}{
|
||||
name={gf},
|
||||
description={Gram-force: 1 gf = 1 g}
|
||||
description={Gram-force: 1\,gf = 1\,g}
|
||||
}
|
||||
\newglossaryentry{QWERTY}{
|
||||
name={QWERTY},
|
||||
@ -76,7 +75,13 @@ description={Keyboard layout commonly used in Germany}
|
||||
|
||||
\newglossaryentry{bottoming}{
|
||||
name={bottoming out},
|
||||
description={Describes the scenario when the typist does not release the key before impact with the bottom of the keyswitch is made}
|
||||
description={Describes the scenario, when the typist does not release the key before impact with the bottom of the keyswitch is made}
|
||||
}
|
||||
|
||||
\newglossaryentry{swapped}{
|
||||
name={hot-swapped},
|
||||
description={Usually describes the process of replacing a part of a device in a
|
||||
quick an simple way, without the need to power off the device}
|
||||
}
|
||||
|
||||
\newglossaryentry{Topre}{
|
||||
@ -87,4 +92,11 @@ description={Topre switches are keyswitches produced by the Japanese company Top
|
||||
\newglossaryentry{MongoDB}{
|
||||
name={MongoDB},
|
||||
description={General purpose, document-based database which name originates from the word humongous}
|
||||
}
|
||||
}
|
||||
|
||||
\newglossaryentry{UX Curve}{
|
||||
name={UX Curve},
|
||||
description={A User Experience
|
||||
Curve is used to assess long-term user experience for a product. Users draw
|
||||
a curve, that represents a certain experience, positive, neutral or negative, for
|
||||
a specific product during a time span} }
|
||||
|
||||
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Loading…
x
Reference in New Issue
Block a user