erwan/phd-thesis
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Remove "see" before section or figure reference

Browse Source
This commit is contained in:
Erwan Normand
2024-09-16 12:57:05 +02:00
parent 8705affcc4
commit 3b66b69fa1
21 changed files with 145 additions and 133 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
3-manipulation/visual-hand/2-method.tex
View File

@@ -25,7 +25,7 @@ As a reference, we considered no visual hand rendering, as is common in AR~\cite
%
Users have no information about hand tracking and no feedback about contact with the virtual objects, other than their movement when touched.
%
As virtual content is rendered on top of the real environment, the hand of the user can be hidden by the virtual objects when manipulating them (see \secref{hands}).
As virtual content is rendered on top of the real environment, the hand of the user can be hidden by the virtual objects when manipulating them (\secref{hands}).
\subsubsection{Occlusion (Occl,~\figref{method/hands-occlusion})}
@@ -94,13 +94,13 @@ Following the guidelines of \textcite{bergstrom2021how} for designing object man
\subsubsection{Push Task}
\label{push-task}
The first manipulation task consists in pushing a virtual object along a real flat surface towards a target placed on the same plane (see \figref{method/task-push}).
The first manipulation task consists in pushing a virtual object along a real flat surface towards a target placed on the same plane (\figref{method/task-push}).
%
The virtual object to manipulate is a small \qty{50}{\mm} blue and opaque cube, while the target is a (slightly) bigger \qty{70}{\mm} blue and semi-transparent volume.
%
At every repetition of the task, the cube to manipulate always spawns at the same place, on top of a real table in front of the user.
%
On the other hand, the target volume can spawn in eight different locations on the same table, located on a \qty{20}{\cm} radius circle centered on the cube, at \qty{45}{\degree} from each other (see again \figref{method/task-push}).
On the other hand, the target volume can spawn in eight different locations on the same table, located on a \qty{20}{\cm} radius circle centered on the cube, at \qty{45}{\degree} from each other (again \figref{method/task-push}).
%
Users are asked to push the cube towards the target volume using their fingertips in any way they prefer.
%
@@ -112,7 +112,7 @@ The task is considered completed when the cube is \emph{fully} inside the target
\subsubsection{Grasp Task}
\label{grasp-task}
The second manipulation task consists in grasping, lifting, and placing a virtual object in a target placed on a different (higher) plane (see \figref{method/task-grasp}).
The second manipulation task consists in grasping, lifting, and placing a virtual object in a target placed on a different (higher) plane (\figref{method/task-grasp}).
%
The cube to manipulate and target volume are the same as in the previous task. However, this time, the target volume can spawn in eight different locations on a plane \qty{10}{\cm} \emph{above} the table, still located on a \qty{20}{\cm} radius circle at \qty{45}{\degree} from each other.
%

2
3-manipulation/visual-hand/3-3-ranks.tex
View File

@@ -16,7 +16,7 @@
%
Friedman tests indicated that both ranking had statistically significant differences (\pinf{0.001}).
%
Pairwise Wilcoxon signed-rank tests with Holm-Bonferroni adjustment were then used on both ranking results (see \secref{metrics}):
Pairwise Wilcoxon signed-rank tests with Holm-Bonferroni adjustment were then used on both ranking results (\secref{metrics}):
\begin{itemize}
\item \textit{Push Ranking}: Occlusion was ranked lower than Contour (\p{0.005}), Skeleton (\p{0.02}), and Mesh (\p{0.03});

2
3-manipulation/visual-hand/3-4-questions.tex
View File

@@ -19,7 +19,7 @@
%
Friedman tests indicated that all questions had statistically significant differences (\pinf{0.001}).
%
Pairwise Wilcoxon signed-rank tests with Holm-Bonferroni adjustment were then used each question results (see \secref{metrics}):
Pairwise Wilcoxon signed-rank tests with Holm-Bonferroni adjustment were then used each question results (\secref{metrics}):
\begin{itemize}
\item \textit{Difficulty}: Occlusion was considered more difficult than Contour (\p{0.02}), Skeleton (\p{0.01}), and Mesh (\p{0.03}).

12
3-manipulation/visual-hand/4-discussion.tex
View File

@@ -3,19 +3,19 @@
We evaluated six visual hand renderings, as described in \secref{hands}, displayed on top of the real hand, in two virtual object manipulation tasks in AR.
During the Push task, the Skeleton hand rendering was the fastest (see \figref{results/Push-CompletionTime-Hand-Overall-Means}), as participants employed fewer and longer contacts to adjust the cube inside the target volume (see \figref{results/Push-ContactsCount-Hand-Overall-Means} and \figref{results/Push-MeanContactTime-Hand-Overall-Means}).
During the Push task, the Skeleton hand rendering was the fastest (\figref{results/Push-CompletionTime-Hand-Overall-Means}), as participants employed fewer and longer contacts to adjust the cube inside the target volume (\figref{results/Push-ContactsCount-Hand-Overall-Means} and \figref{results/Push-MeanContactTime-Hand-Overall-Means}).
%
Participants consistently used few and continuous contacts for all visual hand renderings (see Fig. 3b), with only less than ten trials, carried out by two participants, quickly completed with multiple discrete touches.
Participants consistently used few and continuous contacts for all visual hand renderings (Fig. 3b), with only less than ten trials, carried out by two participants, quickly completed with multiple discrete touches.
%
However, during the Grasp task, despite no difference in completion time, providing no visible hand rendering (None and Occlusion renderings) led to more failed grasps or cube drops (see \figref{results/Grasp-CompletionTime-Hand-Overall-Means} and \figref{results/Grasp-MeanContactTime-Hand-Overall-Means}).
However, during the Grasp task, despite no difference in completion time, providing no visible hand rendering (None and Occlusion renderings) led to more failed grasps or cube drops (\figref{results/Grasp-CompletionTime-Hand-Overall-Means} and \figref{results/Grasp-MeanContactTime-Hand-Overall-Means}).
%
Indeed, participants found the None and Occlusion renderings less effective (see \figref{results/Ranks-Grasp}) and less precise (see \figref{questions}).
Indeed, participants found the None and Occlusion renderings less effective (\figref{results/Ranks-Grasp}) and less precise (\figref{questions}).
%
To understand whether the participants' previous experience might have played a role, we also carried out an additional statistical analysis considering VR experience as an additional between-subjects factor, \ie VR novices vs. VR experts (\enquote{I use it every week}, see \secref{participants}).
%
We found no statistically significant differences when comparing the considered metrics between VR novices and experts.
Interestingly, all visual hand renderings showed grip apertures very close to the size of the virtual cube, except for the None rendering (see \figref{results/Grasp-GripAperture-Hand-Overall-Means}), with which participants applied stronger grasps, \ie less distance between the fingertips.
Interestingly, all visual hand renderings showed grip apertures very close to the size of the virtual cube, except for the None rendering (\figref{results/Grasp-GripAperture-Hand-Overall-Means}), with which participants applied stronger grasps, \ie less distance between the fingertips.
%
Having no visual hand rendering, but only the reaction of the cube to the interaction as feedback, made participants less confident in their grip.
%
@@ -23,7 +23,7 @@ This result contrasts with the wrongly estimated grip apertures observed by \tex
%
Also, while some participants found the absence of visual hand rendering more natural, many of them commented on the importance of having feedback on the tracking of their hands, as observed by \textcite{xiao2018mrtouch} in a similar immersive OST-AR setup.
Yet, participants' opinions of the visual hand renderings were mixed on many questions, except for the Occlusion one, which was perceived less effective than more \enquote{complete} visual hands such as Contour, Skeleton, and Mesh hands (see \figref{questions}).
Yet, participants' opinions of the visual hand renderings were mixed on many questions, except for the Occlusion one, which was perceived less effective than more \enquote{complete} visual hands such as Contour, Skeleton, and Mesh hands (\figref{questions}).
%
However, due to the latency of the hand tracking and the visual hand reacting to the cube, almost all participants thought that the Occlusion rendering to be a \enquote{shadow} of the real hand on the cube.