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appendices.tex
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@ -19,7 +19,7 @@
\end{figure} \end{figure}
\subsection{Collection of available actuation forces for different keyswitch manufacturers} \subsection{Collection of available actuation forces for different keyswitch manufacturers}
\label{sec:a2} \label{app:keyswitch}
To gather information about available actuation forces, the product lines of To gather information about available actuation forces, the product lines of
keyswitches for all well known manufacturers, namely Cherry, Kailh, Gateron, keyswitches for all well known manufacturers, namely Cherry, Kailh, Gateron,

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chap0/sec1.tex
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@ -1,7 +1,7 @@
% Chapter 0 - Proposal % Chapter 0 - Proposal
% Section 1 - Motivation, problem statement and thesis objectives % Section 1 - Motivation, problem statement and thesis objectives
\section{Bachelor Thesis Proposal - Philip Gaber} \section{Bachelor Thesis Proposal - Philip Gaber}
{\huge Impact of personalized, per key, actuation force on efficiency and satisfaction while using mechanical keyboards} {\huge Impact of adjusted, per key, actuation force on efficiency and satisfaction while using mechanical keyboards}
\subsection{Motivation} \subsection{Motivation}
In recent years, computers are used to some extend in almost every industry in In recent years, computers are used to some extend in almost every industry in
Europe \cite{eurostat_ent_w_comp} and China \cite{iresearch_ent_w_comp}. This Europe \cite{eurostat_ent_w_comp} and China \cite{iresearch_ent_w_comp}. This
@ -11,46 +11,55 @@ computers in corporations. Furthermore, according to a statistic published by
access to at least one computer \cite{itu_hh_w_comp}. One of the most used access to at least one computer \cite{itu_hh_w_comp}. One of the most used
devices for data input while operating a computer is the keyboard devices for data input while operating a computer is the keyboard
\parencite[22]{handbook_chi}. Therefore, people who use a computer, either at \parencite[22]{handbook_chi}. Therefore, people who use a computer, either at
home or to fulfill certain tasks at work, are also likely to use a home or to fulfill certain tasks at work, are also likely to use a keyboard. An
keyboard. There are also different mechanisms which are used in keyboard keys to important part of a keyboard is the keyswitch also called keyboard key or
determine if a key is pressed. More commonly used mechanism to date are scissor key. Those keyswitches use, depending on the manufacturer or keyboard type,
switches, mostly used in laptop keyboards, dome/membrane switches, often used in different mechanisms to actuate a keypress. More commonly used mechanism to date
low- to mid-priced keyboards, and mechanical switches which are the main switch are scissor switches, mostly used in laptop keyboards, dome/membrane switches,
type for high-priced and gaming keyboards \cite{ergopedia_keyswitch}. Depending often used in low- to mid-priced keyboards, and mechanical switches which are
on the mechanism and type of key used, it is possible that different force has the main switch type for high-priced and gaming keyboards
to be applied to the key to activate it. Normally, the force required to \cite{ergopedia_keyswitch}. Depending on the mechanism and type of key used, it
activate a key is identical for each key across the keyboard. However, previous is possible that different force has to be applied to the key to activate
research has shown, that there is a disparity in force generated by different it. Normally, the force required to activate a key is identical for each key
fingers \cite{bretz_finger_force}. This raises the question, why there are no across the keyboard. However, previous research has shown, that there is a
keyboards with adjusted actuation forces per finger or even customizable disparity in force generated by different fingers
keyboards, where an individual can select the actuation force for each \cite{bretz_finger_force}. This raises the question, why there are no keyboards
keyswitch. with adjusted actuation forces per finger or even customizable keyboards, where
an individual can select the actuation force for each keyswitch individually.
\subsection{Proposed Objective, Research Question and Hypothesis} \subsection{Proposed Objective, Research Question and Hypothesis}
This thesis is intended to provide an overview of already conducted research in % This thesis is intended to provide an overview of already conducted research in
the domain of keyboards, especially in connection with actuation force and the % the domain of keyboards, especially in connection with actuation force and the
impact of different keyswitches on keyboard users. % impact of different keyswitches on keyboard users.
Because there is no previous research in the particular field of per finger/key % Because there is no previous research in the particular field of per finger/key
actuation force for (mechanical) keyboards and the impact of such customization % actuation force for (mechanical) keyboards and the impact of such customization
on efficiency and comfort, this thesis is also intended to research if this is a % on efficiency and comfort, this thesis is also intended to research if this is a
viable option in comparison to the classic keyboard with uniform actuation % viable option in comparison to the classic keyboard with uniform actuation
force. Therefore the author proposes to answer the question: % force. Therefore the author proposes to answer the question:
This thesis is intended to research if a keyboard with zones of keys, which have
adjusted actuation force depending on the assigned finger for that zone and the
position on the keyboard, is a viable option compared to the standard keyboard
with uniform actuation force across all keyswitches.
\begin{tabular}{p{0.3cm} p{0.5cm} p{13cm} p{0.5cm}} \begin{tabular}{p{0.3cm} p{0.5cm} p{13cm} p{0.5cm}}
& \textbf{\large RQ} & {\Large Does a personalized, per key, actuation force have a positive impact on efficiency and satisfaction?} & \\ & \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?} & \\
\end{tabular} \end{tabular}
\vspace{1em} \vspace{1em}
% TODO: Dissatisfied statt comfort da hohe error rate und dadurch frustriert
% TODO: Bei hypothesen noch error rate bei geschwindigkeit mit einbeziehen
% ASK: Doch noch comfort mit einbeziehen?
\begin{longtable}{p{0.3cm} p{0.5cm} p{13cm} p{0.5cm}} \begin{longtable}{p{0.3cm} p{0.5cm} p{13cm} p{0.5cm}}
& \textbf{H1} & Lower key actuation force improves typing speed over higher key actuation force and therefore enhances efficiency. & \\ & \textbf{H1} & Lower key actuation force improves typing speed over higher key actuation force (efficiency - speed). & \\
& & & \\ & & & \\
& \textbf{H2} & Higher key actuation force decreases typing errors compared to lower key actuation force, which improves efficiency. & \\ & \textbf{H2} & Higher key actuation force decreases typing errors compared to lower key actuation force (efficiency - error rate). & \\
& & & \\ & & & \\
& \textbf{H3} & Keys with lower actuation force are perceived as more satisfactory to write with then keys with higher actuation force. & \\ & \textbf{H3} & Keys with lower actuation force are perceived as more satisfactory to write with than keys with higher actuation force. & \\
& & & \\ & & & \\
& \textbf{H4} & Users perform better and feel more satisfied while using Keyboards with personalized/adjusted key actuation force then without the personalization/adjustment. & \\ & \textbf{H4} & Users perform better and feel more satisfied while using Keyboards with adjusted key actuation force than without the adjustment. & \\
\end{longtable} \end{longtable}
@ -60,8 +69,8 @@ force. Therefore the author proposes to answer the question:
Main target group to recruit participants for the research study from are Main target group to recruit participants for the research study from are
personal contacts and fellow students. It is planned to recruit ~20 participants personal contacts and fellow students. It is planned to recruit ~20 participants
in total. Participants are required to type with more than just one in total. Participants are required to type with more than just one finger per
finger. Therefore touch typing is not a mandatory but helpful skill to hand. Thus, touch typing is not a mandatory but helpful skill to
participate. The age distribution for the subjects is estimated to be between 18 participate. The age distribution for the subjects is estimated to be between 18
and 56 years. The average typing speed should be known prior to the main and 56 years. The average typing speed should be known prior to the main
experiment. Therefore, a typing speed test should be performed on the subject's experiment. Therefore, a typing speed test should be performed on the subject's
@ -73,7 +82,36 @@ study.
\subsection{Study design} \subsection{Study design}
The experiment should consist of a experimental group and a control group. The text used for the typing test should be easily understandable. Therefore the text has to be evaluated with the help of a Flesch-Kncaid scala (understandability of text). The experiment should consist of a experimental group and a control group. The
control group will perform all typing tests with the same keyboard. The text
used for the typing test should be easily understandable. Therefore, the text
has to be evaluated with the help of a Flesch-Kincaid scala \cite{flesch_fre}
adjusted for German language \cite{amstad_fre}.
\begin{equation}\label{fre_german}
FRE_{deutsch} = 180 - \underbrace{ASL}_{\mathclap{\text{Average Sentence Length}}} - (58,5 * \overbrace{ASW}^{\mathclap{\text{Average Syllables per Word}}})
\end{equation}
The adjusted formula (\ref{fre_german}) to estimate the understandability of the
texts used in this experiment usually yields a number in the range of
\([0;100]\) called the \gls{FRE}. Higher \gls{FRE}s refer to better
understandability and thus the texts used in this experiment all have to fulfill
the requirement of a \gls{FRE} \(> 60\) which represents a standard text
\cite{amstad_fre} and \cite{flesch_fre}.
One typing test will consist of several smaller, randomly chosen, texts
snippets. The length of the snippets has to be between 100 and 400 characters
and a snippet has meet the \gls{FRE} requirement. The snippets are generated by
volunteers via the web interface of the platform used in this experiment which
can be seen in Figure \ref{gott:contribute_text}.
\begin{figure}[h!]
\centering
\includegraphics[width=0.42\textwidth]{images/gott_contribute_text.png}
\caption{Go TyingTest (GoTT) - Text contribution section }
\label{gott:contribute_text}
\end{figure}
% 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? % 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?
@ -81,60 +119,73 @@ The experiment should consist of a experimental group and a control group. The t
\begin{enumerate} \begin{enumerate}
\item Pre-Test questionnaire to gather demographic and other relevant \item Pre-Test questionnaire to gather demographic and other relevant
information (age, gender, dominant hand, touch typing experience, average information e.g., touch typist, average \gls{KB} usage per day and previous
\gls{KB} usage per day, previous medical conditions affecting the result of medical conditions affecting the result of the study \gls{RSI}, \gls{CTS},
the study -> \gls{RSI}, \gls{CTS}, etc.) (5 min) etc. (5 min)
% ASK: Medical conditions OK? % ASK: Medical conditions OK?
\item Adjustment of test environment (Chair height, monitor height, etc.) (2 min) \item Adjustment of test environment (Chair height, monitor height, etc.) (2 min)
\item Familiarization with the typing test (5 min) \item Familiarization with the typing test (5 min)
\item \textbf{Main-Test part 1 (H1-H3):} Typing tests (2x 5 min per \gls{KB} + \item Familiarization with the keyboard (5 min)
5 min break in between tests) with different actuation forces for the whole \item \textbf{Main-Test part 1 (H1-H3):} In this part the subject has to take
keyboard (35 \gls{g}, 50 \gls{g}, 80 \gls{g}). These specific values are the two, 5 minute, typing tests per keyboard, with a total of 3 keyboards
results of a self conducted comparison between the product lines of most major (\gls{KB} A, \gls{KB} B, \gls{KB} C). After each typing test, the subject has
keyswitch manufacturers. The results show, that the lowest average force for to fill out the post typing test keyboard comfort questionnaire. Each keyboard
keyswitches available is 35 \gls{g}, the highest average force is 80 \gls{g}, is equipped with one set of keyswitches and therefore provides one of the
and the most common offered force is 50 \gls{g}. The keyboard has an ISO type following, uniform, actuation forces across the whole keyboard: 35 \gls{g}, 50
and QWERTZ layout to match the subjects day-to-day layout and keyboard \gls{g} or 80 \gls{g}. These specific values are the results of a self
format. The keyboard uses mechanical keyswitches which are hot-pluggable and conducted comparison between the product lines of most major keyswitch
therefore can be changed after each typing test while participants take a manufacturers. The results shown in appendix \ref{app:keyswitch} yield, that
break. The order for the keyswitch actuation forces and texts for the the lowest broadly available force for keyswitches is 35 \gls{g}, the highest
broadly available force is 80 \gls{g}, and the most common offered force is 50
\gls{g}. The keyboards used in this experiment are visually identical, ISO/IEC
9995-1 conform \cite{iso9995-1} and provide a \gls{QWERTZ} layout to match the subjects
day-to-day layout and keyboard format. All keyboards are equipped with linear
mechanical keyswitches from one manufacturer to minimize differences in haptic
and sound while typing. The order for the keyboards and texts for the
individual tests is randomized and across subjects counterbalanced to mitigate individual tests is randomized and across subjects counterbalanced to mitigate
order effects \cite{statist_counterbalancing}. \textbf{(total: 60 min)} order effects \cite{statist_counterbalancing}. \textbf{(total: 65 min)}
\begin{enumerate} \begin{enumerate}
\item First typing test (15 min) \item First typing test with \gls{KB} A (5 min) \\
\item Change of keyswitches + follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min) Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min)
\item Second typing test (15 min) \item Second typing test with \gls{KB} A (5 min) \\
\item Change of keyswitches + follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min) Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min)
\item Third typing test (15 min) \item First typing test with \gls{KB} B (5 min) \\
\item Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min) Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min)
\item Second typing test with \gls{KB} B (5 min) \\
Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min)
\item First typing test with \gls{KB} C (5 min) \\
Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min)
\item Second typing test with \gls{KB} C (5 min) \\
Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min)
\end{enumerate} \end{enumerate}
\item \textbf{Main-Test part 2 (H4):} Another typing test to compare the \item \textbf{Main-Test part 2 (H4):} Another typing test to compare the
results of keyboards with uniform actuation force to keyboards with adjusted results of keyboards with uniform actuation force to keyboards with adjusted
actuation force per finger/key. \textbf{(total: 50 min)} actuation force per finger/key. Typing tests (2x 5 min + 5 min break in
between tests) \textbf{(total: (i) 60 min / (ii) 45 min)}
\begin{enumerate} \begin{enumerate}
\item Typing sample text on an analog keyboard with high actuation force (150 \item \textbf{Alternative Methods:}
\gls{g}) to measure difference in typing force per finger and key. The subject \begin{enumerate}
should be forced to press every relevant key (letters, digits, common special \item \textbf{Personalized keyboard:} Typing sample text on an analog
characters) at least 5 times (can be replaced by a keyboard that is equipped keyboard with high actuation force (150 \gls{g}) (less accurate) or on a
with different zones of keyswitches that use appropriate actuation forces) (30 normal keyboard which is placed on top of a force plate (more accurate) to
min including adjustment of keyboard and familiarization) measure difference in typing force per finger and key. The subject should
\item Typing speed tests on the adjusted keyboard (15 min) with follow-up ISO be forced to press every relevant key (letters, digits, common special
keyboard comfort questionnaire (ISO9241-410) (5 min) characters) at least 5 times (Measurement: 15 min, Keyboard adjustment: 15
min)
\item \textbf{Adjusted keyboard:} Keyboard that is equipped with different
zones of keyswitches that use appropriate actuation forces according to
finger strength differences and key position. (Keyboard adjustment: 15 min)
\end{enumerate}
\item Familiarization with the keyboard (10 min)
\item First typing test on the personalized/adjusted keyboard (5 min) \\
Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min)
\item Second typing test on the personalized/adjusted keyboard (5 min) \\
Follow-up ISO keyboard comfort questionnaire (ISO9241-410) (5 min)
\end{enumerate} \end{enumerate}
\end{enumerate} \end{enumerate}
% More than 60 min is probably to long
With all those tasks, the experiment would exceed 60 minutes. Therefore, the
additional typing test with the adjusted keyboard could take place on another
day or the initial tests to figure out the performance and comfort for different
key actuation forces could be left out entirely and only the adjusted keyboard
is compared to the personal keyboard of each participant.
All tests could be enhanced with the use of \gls{EMG} measurement and/or additional force measurement (with force plates) during the typing tests. All tests could be enhanced with the use of \gls{EMG} measurement and/or additional force measurement (with force plates) during the typing tests.
This test scenario is inspired by the tests conducted by \cite{kim_typingforces}. This test scenario is inspired by the tests conducted by \cite{kim_typingforces}.
% TODO: Dissatisfied statt comfort da hohe error rate und dadurch frustriert
% TODO: Bei hypothesen noch error rate bei geschwindigkeit mit einbeziehen

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glossary.tex
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@ -4,6 +4,7 @@
\newacronym{EMG}{EMG}{Electromyography} \newacronym{EMG}{EMG}{Electromyography}
\newacronym{CTS}{CTS}{Carpal Tunnel Syndrome} \newacronym{CTS}{CTS}{Carpal Tunnel Syndrome}
\newacronym{RSI}{RSI}{Repetitive Strain Injury} \newacronym{RSI}{RSI}{Repetitive Strain Injury}
\newacronym{FRE}{FRE}{Flesch Reading Ease Score}
\newglossaryentry{cN}{ \newglossaryentry{cN}{
name={cN}, name={cN},
@ -16,4 +17,8 @@ description={Gram: 1 g $ \approx $ 0.97 cN}
\newglossaryentry{gf}{ \newglossaryentry{gf}{
name={gf}, name={gf},
description={Gram-force: 1 gf = 1 g} description={Gram-force: 1 gf = 1 g}
}
\newglossaryentry{QWERTZ}{
name={QWERTZ},
description={Keyboard layout commonly used in Germany}
} }

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proposal.tex
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@ -52,6 +52,8 @@
\usepackage{multirow} \usepackage{multirow}
\usepackage{colortbl} \usepackage{colortbl}
\usepackage{mathtools}
%----Kopfzeile----------------------------------------------------------------------- %----Kopfzeile-----------------------------------------------------------------------
\usepackage{scrlayer-scrpage} % Aufruf KOMA-Skript für Kopfzeilen \usepackage{scrlayer-scrpage} % Aufruf KOMA-Skript für Kopfzeilen
%----Separator Header/Footer--------------------------------------------------------- %----Separator Header/Footer---------------------------------------------------------

139
ref_shelf.bib
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@ -1,43 +1,49 @@
% Encoding: UTF-8 % Encoding: UTF-8
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author = "Eurostat", (UK) and European Union (EU-28 countries) from 2010 to 2015
booktitle = "Statista", [Graph]},
url= "https://www-statista-com.thi.idm.oclc.org/statistics/275306/share-of-enterprises-who-used-computers-in-the-uk-and-eu-since-2010/", author = {Eurostat},
year = 2016, booktitle = {Statista},
month = may, url =
urldate = {2020-10-12} {https://www-statista-com.thi.idm.oclc.org/statistics/275306/share-of-enterprises-who-used-computers-in-the-uk-and-eu-since-2010/},
year = 2016,
month = {may},
urldate = {2020-10-12}
} }
@incollection{iresearch_ent_w_comp, @incollection{iresearch_ent_w_comp,
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author = "iResearch", [Graph]},
booktitle = "Statista", author = {iResearch},
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year = 2018, url =
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urldate = {2020-10-12} year = 2018,
month = {jul},
urldate = {2020-10-12}
} }
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title = "Share of households with a computer at home worldwide from 2005 to 2019 [Graph]", title = {Share of households with a computer at home worldwide from
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} }
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} }
@online{ergopedia_keyswitch, @online{ergopedia_keyswitch,
@ -47,18 +53,21 @@ url = {http://www.ergopedia.ca/ergonomic_concepts/Mechanical_Keyswitches_Membran
urldate = {2020-10-12} urldate = {2020-10-12}
} }
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{http://www.sciencedirect.com/science/article/pii/S000368701400043X},
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Christy A. Harper and Peter W. Johnson}
} }
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@ -69,16 +78,44 @@ urldate = {2020-10-12}
} }
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{http://www.sciencedirect.com/science/article/pii/B9780444818621500674},
author = {Raymond S. Nickerson and Thomas K. Landauer}
} }
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author = {International Organization for Standardization},
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year = 2018
}
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}
@article{flesch_fre,
title={A new readability yardstick.},
author={Flesch, Rudolph},
journal={Journal of Applied Psychology},
volume={32},
number={3},
pages={221-233},
year={1948},
publisher={American Psychological Association}
}