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Split xr-perception chapter

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Erwan Normand
2024-09-24 15:09:19 +02:00
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2-perception/xr-perception/3-experiment.tex
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@@ -25,7 +25,6 @@ In a two-alternative forced choice (2AFC) task, participants compared the roughn
%
In order not to influence the perception, as vision is an important source of information and influence for the perception of texture \cite{bergmanntiest2007haptic,yanagisawa2015effects,vardar2019fingertip}, the touched surface was visually a uniform white; thus only the visual aspect of the hand and the surrounding environment is changed.
\subsection{Participants}
\label{participants}
@@ -43,7 +42,6 @@ Participants were recruited at the university on a voluntary basis.
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They all signed an informed consent form before the user study and were unaware of its purpose.
\subsection{Apparatus}
\label{apparatus}
@@ -99,7 +97,6 @@ They also wore headphones with a pink noise masking the sound of the voice-coil.
%
The user study was held in a quiet room with no windows.
\subsection{Procedure}
\label{procedure}
@@ -135,15 +132,14 @@ All textures were rendered as described in \secref{texture_generation} with peri
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Preliminary studies allowed us to determine a range of amplitudes that could be felt by the participants and were not too uncomfortable, and the reference texture was chosen to be the one with the middle amplitude.
\subsection{Experimental Design}
\label{experimental_design}
The user study was a within-subjects design with two factors:
%
\begin{itemize}
\item \factor{Visual Rendering}, consisting of the augmented or virtual view of the environment, the hand and the wearable haptic device, with 3 levels: real environment and real hand view without any visual augmentation (\figref{renderings}, \level{Real}), real environment and hand view with the virtual hand (\figref{renderings}, \level{Mixed}) and virtual environment with the virtual hand (\figref{renderings}, \level{Virtual}).
\item \factor{Amplitude Difference}, consisting of the difference in amplitude between the comparison and the reference textures, with 6 levels: \qtylist{0; +-12.5; +-25.0; +-37.5}{\%}.
\item \factor{Visual Rendering}, consisting of the augmented or virtual view of the environment, the hand and the wearable haptic device, with 3 levels: real environment and real hand view without any visual augmentation (\figref{renderings}, \level{Real}), real environment and hand view with the virtual hand (\figref{renderings}, \level{Mixed}) and virtual environment with the virtual hand (\figref{renderings}, \level{Virtual}).
\item \factor{Amplitude Difference}, consisting of the difference in amplitude between the comparison and the reference textures, with 6 levels: \qtylist{0; +-12.5; +-25.0; +-37.5}{\%}.
\end{itemize}
A trial consisted on a two-alternative forced choice (2AFC) task where a participant had to touch two virtual vibrotactile textures one after the other and decide which one was the roughest.
@@ -154,7 +150,6 @@ Within each condition, the order of presentation of the reference and comparison
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A total of 3 visual renderings \x 6 amplitude differences \x 2 texture presentation order \x 3 repetitions = 107 trials were performed by each participant.
\subsection{Collected Data}
\label{collected_data}
@@ -172,44 +167,44 @@ For all questions, participants were shown only labels (\eg \enquote{Not at all}
\newcommand{\scalegroup}[2]{\multirow{#1}{1\linewidth}{#2}}
\begin{tabwide}{questions}
{Questions asked to participants after each \factor{Visual Rendering} block of trials.}
[
Unipolar scale questions were 5-point Likert scales (1 = Not at all, 2 = Slightly, 3 = Moderately, 4 = Very and 5 = Extremely), and %
bipolar scale questions were 7-point Likert scales (1 = Extremely A, 2 = Moderately A, 3 = Slightly A, 4 = Neither A nor B, 5 = Slightly B, 6 = Moderately B, 7 = Extremely B), %
where A and B are the two poles of the scale (indicated in parentheses in the Scale column of the questions).
%, and NASA TLX questions were bipolar 100-points scales (0 = Very Low and 100 = Very High, except for Performance where 0 = Perfect and 100 = Failure). %
Participants were shown only the labels for all questions.
]
\begin{tabularx}{\linewidth}{l X p{0.2\linewidth}}
\toprule
\textbf{Code} & \textbf{Question} & \textbf{Scale} \\
\midrule
Texture Agency & Did the tactile sensations of texture seem to be caused by your movements? & \scalegroup{4}{Unipolar (1-5)} \\
Texture Realism & How realistic were the tactile textures? & \\
Texture Plausibility & Did you feel like you were actually touching textures? & \\
Texture Latency & Did the sensations of texture seem to lag behind your movements? & \\
\midrule
Vibration Location & Did the vibrations seem to come from the surface you were touching or did you feel them on the top of your finger? & Bipolar (1=surface, 7=top of finger) \\
Vibration Strength & Overall, how weak or strong were the vibrations? & Bipolar (1=weak, 7=strong) \\
Device Distraction & To what extent did the vibrotactile device distract you from the task? & \scalegroup{2}{Unipolar (1-5)} \\
Device Discomfort & How uncomfortable was it to use the vibrotactile device? & \\
\midrule
Hand Agency & Did the movements of the virtual hand seem to be caused by your movements? & \scalegroup{5}{Unipolar (1-5)} \\
Hand Similarity & How similar was the virtual hand to your own hand in appearance? & \\
Hand Ownership & Did you feel the virtual hand was your own hand? & \\
Hand Latency & Did the virtual hand seem to lag behind your movements? & \\
Hand Distraction & To what extent did the virtual hand distract you from the task? & \\
Hand Reference & Overall, did you focus on your own hand or the virtual hand to complete the task? & Bipolar (1=own hand, 7=virtual hand) \\
\midrule
Virtual Realism & How realistic was the virtual environment? & \scalegroup{2}{Unipolar (1-5)} \\
Virtual Similarity & How similar was the virtual environment to the real one? & \\
%\midrule
%Mental Demand & How mentally demanding was the task? & \scalegroup{6}{Bipolar (0-100)} \\
%Temporal Demand & How hurried or rushed was the pace of the task? & \\
%Physical Demand & How physically demanding was the task? & \\
%Performance & How successful were you in accomplishing what you were asked to do? & \\
%Effort & How hard did you have to work to accomplish your level of performance? & \\
%Frustration & How insecure, discouraged, irritated, stressed, and annoyed were you? & \\
\bottomrule
\end{tabularx}
{Questions asked to participants after each \factor{Visual Rendering} block of trials.}
[
Unipolar scale questions were 5-point Likert scales (1 = Not at all, 2 = Slightly, 3 = Moderately, 4 = Very and 5 = Extremely), and %
bipolar scale questions were 7-point Likert scales (1 = Extremely A, 2 = Moderately A, 3 = Slightly A, 4 = Neither A nor B, 5 = Slightly B, 6 = Moderately B, 7 = Extremely B), %
where A and B are the two poles of the scale (indicated in parentheses in the Scale column of the questions).
%, and NASA TLX questions were bipolar 100-points scales (0 = Very Low and 100 = Very High, except for Performance where 0 = Perfect and 100 = Failure). %
Participants were shown only the labels for all questions.
]
\begin{tabularx}{\linewidth}{l X p{0.2\linewidth}}
\toprule
\textbf{Code} & \textbf{Question} & \textbf{Scale} \\
\midrule
Texture Agency & Did the tactile sensations of texture seem to be caused by your movements? & \scalegroup{4}{Unipolar (1-5)} \\
Texture Realism & How realistic were the tactile textures? & \\
Texture Plausibility & Did you feel like you were actually touching textures? & \\
Texture Latency & Did the sensations of texture seem to lag behind your movements? & \\
\midrule
Vibration Location & Did the vibrations seem to come from the surface you were touching or did you feel them on the top of your finger? & Bipolar (1=surface, 7=top of finger) \\
Vibration Strength & Overall, how weak or strong were the vibrations? & Bipolar (1=weak, 7=strong) \\
Device Distraction & To what extent did the vibrotactile device distract you from the task? & \scalegroup{2}{Unipolar (1-5)} \\
Device Discomfort & How uncomfortable was it to use the vibrotactile device? & \\
\midrule
Hand Agency & Did the movements of the virtual hand seem to be caused by your movements? & \scalegroup{5}{Unipolar (1-5)} \\
Hand Similarity & How similar was the virtual hand to your own hand in appearance? & \\
Hand Ownership & Did you feel the virtual hand was your own hand? & \\
Hand Latency & Did the virtual hand seem to lag behind your movements? & \\
Hand Distraction & To what extent did the virtual hand distract you from the task? & \\
Hand Reference & Overall, did you focus on your own hand or the virtual hand to complete the task? & Bipolar (1=own hand, 7=virtual hand) \\
\midrule
Virtual Realism & How realistic was the virtual environment? & \scalegroup{2}{Unipolar (1-5)} \\
Virtual Similarity & How similar was the virtual environment to the real one? & \\
%\midrule
%Mental Demand & How mentally demanding was the task? & \scalegroup{6}{Bipolar (0-100)} \\
%Temporal Demand & How hurried or rushed was the pace of the task? & \\
%Physical Demand & How physically demanding was the task? & \\
%Performance & How successful were you in accomplishing what you were asked to do? & \\
%Effort & How hard did you have to work to accomplish your level of performance? & \\
%Frustration & How insecure, discouraged, irritated, stressed, and annoyed were you? & \\
\bottomrule
\end{tabularx}
\end{tabwide}