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

Add acronym in intro

Browse Source
This commit is contained in:
Erwan Normand
2024-08-10 17:25:32 +02:00
parent 65f02edaf6
commit 7b5988c798
3 changed files with 114 additions and 106 deletions
Download Patch File Download Diff File Expand all files Collapse all files

184
1-introduction/introduction/introduction.tex
View File

@@ -1,7 +1,7 @@
\chapter{Introduction} \chapter{Introduction}
\mainlabel{introduction} \mainlabel{introduction}
This thesis presents research on the perception and interaction directly with the hand with real and virtual everyday objects, visually and haptically augmented using immersive augmented reality and wearable haptic devices. This thesis presents research on the perception and interaction directly with the hand with real and virtual everyday objects, visually and haptically augmented using immersive \AR and wearable haptic devices.
\section{Visual and Tactile Object Augmentations} \section{Visual and Tactile Object Augmentations}
@@ -69,9 +69,9 @@ A wide range of wearable haptic devices have been developed to provide the user
% %
\figref{wearable-haptics} shows some examples of different wearable haptic devices with different form factors and rendering capabilities. \figref{wearable-haptics} shows some examples of different wearable haptic devices with different form factors and rendering capabilities.
% %
Their portability, \ie their small form factor, light weight and unobtrusiveness, makes them particularly promising for everyday use in a variety of applications such as robotics, teleoperation, virtual reality (VR), and social interactions~\autocite{pacchierotti2017wearable,culbertson2018haptics}. Their portability, \ie their small form factor, light weight and unobtrusiveness, makes them particularly promising for everyday use in a variety of applications such as robotics, teleoperation, \VR, and social interactions~\autocite{pacchierotti2017wearable,culbertson2018haptics}.
% %
But their use in combination with augmented reality (AR) has been little explored so far. But their use in combination with \AR has been little explored so far.
\begin{subfigs}{wearable-haptics}{% \begin{subfigs}{wearable-haptics}{%
Wearable haptic devices can render sensations on the skin as feedback to real or virtual objects being touched. Wearable haptic devices can render sensations on the skin as feedback to real or virtual objects being touched.
@@ -91,21 +91,21 @@ But their use in combination with augmented reality (AR) has been little explore
\subsectionstarbookmark{Augmented Reality Is Not Only Visual} \subsectionstarbookmark{Augmented Reality Is Not Only Visual}
AR integrates virtual content into the real world perception, creating the illusion of a unique augmented environment (AE). \AR integrates virtual content into the real world perception, creating the illusion of a unique \AE.
% %
It thus promises natural and seamless interaction with the physical and digital objects (and their combination) directly with our hands. It thus promises natural and seamless interaction with the physical and digital objects (and their combination) directly with our hands.
% %
It is technically and conceptually closely related to VR, which replaces the real environment (RE) perception with a virtual environment (VE). It is technically and conceptually closely related to \VR, which replaces the \RE perception with a \VE.
% %
AR and VR can be placed on a reality-virtuality (RV) continuum, as proposed by \textcite{milgram1994taxonomy} and illustrated in \figref{rv-continuum}\footnote{On the RV continuum of \textcite{milgram1994taxonomy}, augmented virtuality is also considered, as the incorporation of real objects to a VE, and is placed between AR and VR. For simplicity, we only consider AR and VR in this thesis.}. \AR and \VR can be placed on a \RV continuum, as proposed by \textcite{milgram1994taxonomy} and illustrated in \figref{rv-continuum}\footnote{On the \RV continuum of \textcite{milgram1994taxonomy}, augmented virtuality is also considered, as the incorporation of real objects to a \VE, and is placed between \AR and \VR. For simplicity, we only consider \AR and \VR in this thesis.}.
% %
It describes the degree of RV of the environment along an axis, with one end being the RE and the other end being a pure VE, \ie indistinguishable from the real world (such as \emph{The Matrix} movies or the \emph{Holodeck} in the \emph{Star Trek} series). It describes the degree of \RV of the environment along an axis, with one end being the \RE and the other end being a pure \VE, \ie indistinguishable from the real world (such as \emph{The Matrix} movies or the \emph{Holodeck} in the \emph{Star Trek} series).
% %
Between these two extremes lies mixed reality (MR), which comprises AR and VR as different levels of mixing real and virtual environments~\autocite{skarbez2021revisiting}. Between these two extremes lies \MR, which comprises \AR and \VR as different levels of mixing real and virtual environments~\autocite{skarbez2021revisiting}.
% %
AR/VR is most often understood as addressing only the visual sense, and as haptics, it can take many forms as a user interface. \AR/\VR is most often understood as addressing only the visual sense, and as haptics, it can take many forms as a user interface.
% %
The most mature devices are head-mounted displays (HMDs), which are portable headsets worn directly on the head, providing the user with an immersive AE/VE. The most mature devices are \HMDs, which are portable headsets worn directly on the head, providing the user with an immersive \AE/\VE.
\begin{subfigs}{rv-continuums}{Reality-virtuality (\RV) continuums. \begin{subfigs}{rv-continuums}{Reality-virtuality (\RV) continuums.
}[ }[
@@ -116,29 +116,29 @@ The most mature devices are head-mounted displays (HMDs), which are portable hea
\subfig[0.54]{visuo-haptic-rv-continuum3} \subfig[0.54]{visuo-haptic-rv-continuum3}
\end{subfigs} \end{subfigs}
AR/VR can also be extended to render for sensory modalities other than vision. \AR/\VR can also be extended to render for sensory modalities other than vision.
% %
In particular, \textcite{jeon2009haptic} proposed extending the RV continuum to include haptic feedback by decoupling into two orthogonal haptic and visual axes (see \figref{visuo-haptic-rv-continuum3}). In particular, \textcite{jeon2009haptic} proposed extending the \RV continuum to include haptic feedback by decoupling into two orthogonal haptic and visual axes (see \figref{visuo-haptic-rv-continuum3}).
% %
The combination of the two axes defines 9 types of visuo-haptic environments, with 3 possible levels of RV for each visual or haptic axis (real, augmented, virtual). The combination of the two axes defines 9 types of visuo-haptic environments, with 3 possible levels of \RV for each visual or haptic axis (real, augmented, virtual).
% %
For example, a visual augmented environment (vAE) that uses a tangible (touchable) object as a proxy to manipulate virtual content is considered a haptic real environment (hRE; see \figref{kahl2023using}; bottom middle cell in \figref{visuo-haptic-rv-continuum3}), whereas a device that provides synthetic haptic feedback when touching a virtual object (VO) is considered a haptic virtual environment (hVE; see \figref{meli2018combining}; top middle cell in \figref{visuo-haptic-rv-continuum3}). For example, a \vAE that uses a tangible (touchable) object as a proxy to manipulate virtual content is considered a \glsdisp{hRE}{\acrlong{hRE}} (\acrshort{hRE}; see \figref{kahl2023using}; bottom middle cell in \figref{visuo-haptic-rv-continuum3}), whereas a device that provides synthetic haptic feedback when touching a \VO is considered a \glsdisp{hVE}{\acrlong{hVE}} (\acrshort{hVE}; see \figref{meli2018combining}; top middle cell in \figref{visuo-haptic-rv-continuum3}).
% %
Haptic augmented reality (hAR) is then the combination of real and virtual haptic stimuli~\autocite{bhatia2024augmenting} (middle row in \figref{visuo-haptic-rv-continuum3}). \Gls{hAR} is then the combination of real and virtual haptic stimuli~\autocite{bhatia2024augmenting} (middle row in \figref{visuo-haptic-rv-continuum3}).
% %
In particular, it has been implemented by enhancing the haptic perception of tangible objects by providing timely tactile stimuli using wearable haptics. In particular, it has been implemented by enhancing the haptic perception of tangible objects by providing timely tactile stimuli using wearable haptics.
% %
\figref{salazar2020altering} shows an example of modifying the perceived stiffness of a tangible object in VR using simultaneous pressure feedback on the finger (left middle cell in \figref{visuo-haptic-rv-continuum3}). \figref{salazar2020altering} shows an example of modifying the perceived stiffness of a tangible object in \VR using simultaneous pressure feedback on the finger (left middle cell in \figref{visuo-haptic-rv-continuum3}).
% %
\figref{bau2012revel} shows another example of visuo-haptic AR rendering of texture when running the finger on a tangible surface (middle cell in the two axes in \figref{visuo-haptic-rv-continuum3}). \figref{bau2012revel} shows another example of visuo-haptic \AR rendering of texture when running the finger on a tangible surface (middle cell in the two axes in \figref{visuo-haptic-rv-continuum3}).
Current (visual) AR systems often lack haptic feedback, creating a deceptive and incomplete user experience when reaching the VE with the hand. Current (visual) \AR systems often lack haptic feedback, creating a deceptive and incomplete user experience when reaching the \VE with the hand.
% %
All visual VOs are inherently intangible and cannot physically constrain a user's hand, making it difficult to perceive their properties congruently and interact with them with confidence and efficiency. All visual \VOs are inherently intangible and cannot physically constrain a user's hand, making it difficult to perceive their properties congruently and interact with them with confidence and efficiency.
% %
It is therefore necessary to provide haptic feedback that is consistent with the vAE and ensures the best possible user experience. It is therefore necessary to provide haptic feedback that is consistent with the \vAE and ensures the best possible user experience.
% %
The integration of wearable haptics with AR seems to be one of the most promising solutions, but it remains challenging due to their many respective characteristics and the additional constraints of combining them. The integration of wearable haptics with \AR seems to be one of the most promising solutions, but it remains challenging due to their many respective characteristics and the additional constraints of combining them.
\begin{subfigs}{visuo-haptic-environments}{ \begin{subfigs}{visuo-haptic-environments}{
Visuo-haptic environments with different degrees of reality-virtuality. Visuo-haptic environments with different degrees of reality-virtuality.
@@ -158,25 +158,25 @@ The integration of wearable haptics with AR seems to be one of the most promisin
\section{Research Challenges of Wearable Visuo-Haptic Augmented Reality} \section{Research Challenges of Wearable Visuo-Haptic Augmented Reality}
The integration of wearable haptics with AR to create a visuo-haptic augmented environment (vhAE) is complex and presents many perceptual and interaction challenges, \ie sensing the AE and acting effectively upon it. The integration of wearable haptics with \AR to create a \vhAE is complex and presents many perceptual and interaction challenges, \ie sensing the \AE and acting effectively upon it.
% %
We are particularly interested in enabling direct contact and manipulation of virtual and augmented objects with the bare hand. We are particularly interested in enabling direct contact and manipulation of virtual and augmented objects with the bare hand.
% %
Our goal is to enable congruent, intuitive and seamless perception of and interaction with the vhAE. Our goal is to enable congruent, intuitive and seamless perception of and interaction with the \vhAE.
The experience of such a vhAE relies on an interaction loop with the user, as illustrated in \figref{interaction-loop}. The experience of such a \vhAE relies on an interaction loop with the user, as illustrated in \figref{interaction-loop}.
% %
The RE and the user's hand are tracked in real time by sensors and reconstructed in visual and haptic VEs. The \RE and the user's hand are tracked in real time by sensors and reconstructed in visual and haptic VEs.
% %
The interactions between the virtual hand and objects are then simulated and rendered as visual and haptic feedback to the user using an AR headset and a wearable haptic device. The interactions between the virtual hand and objects are then simulated and rendered as visual and haptic feedback to the user using an \AR headset and a wearable haptic device.
% %
Because the visuo-haptic VE is displayed in real time, colocalized and aligned with the real one, the user is given the illustion of directly perceiving and interacting with the virtual content as if it were part of the RE. Because the visuo-haptic \VE is displayed in real time, colocalized and aligned with the real one, the user is given the illustion of directly perceiving and interacting with the virtual content as if it were part of the \RE.
\fig{interaction-loop}{% \fig{interaction-loop}{%
The interaction loop between a user and a visuo-haptic augmented environment. % The interaction loop between a user and a visuo-haptic augmented environment. %
}[% }[%
One interact with the visual (in blue) and haptic (in red) virtual environment through a virtual hand (in purple) interaction technique that tracks real hand movements and simulates contact with VOs. % One interact with the visual (in blue) and haptic (in red) virtual environment through a virtual hand (in purple) interaction technique that tracks real hand movements and simulates contact with \VOs. %
The virtual environment is rendered back to the user colocalized with the real one (in gray) using a visual AR headset and a wearable haptic device. % The virtual environment is rendered back to the user colocalized with the real one (in gray) using a visual \AR headset and a wearable haptic device. %
] ]
%This to ensure the best possible user experience, taking into account the current capabilities and limitations of wearable haptics and augmented reality technologies. %This to ensure the best possible user experience, taking into account the current capabilities and limitations of wearable haptics and augmented reality technologies.
@@ -188,74 +188,74 @@ In this context, we identify two main research challenges that we address in thi
\item enabling effective interaction with the augmented environment. \item enabling effective interaction with the augmented environment.
\end{enumerate*} \end{enumerate*}
% %
Each of these challenges also raises numerous design, technical and human issues specific to each of the two types of feedback, wearable haptics and immersive AR, as well as multimodal rendering and user experience issues in integrating these two sensorimotor feedbacks into a coherent and seamless vhAE. Each of these challenges also raises numerous design, technical and human issues specific to each of the two types of feedback, wearable haptics and immersive \AR, as well as multimodal rendering and user experience issues in integrating these two sensorimotor feedbacks into a coherent and seamless \vhAE.
%These challenges are illustrated in the visuo-haptic interaction loop in \figref{interaction-loop}. %These challenges are illustrated in the visuo-haptic interaction loop in \figref{interaction-loop}.
\subsectionstarbookmark{Provide Plausible and Coherent Visuo-Haptic Augmentations} \subsectionstarbookmark{Provide Plausible and Coherent Visuo-Haptic Augmentations}
Many haptic devices have been designed and evaluated specifically for use in VR, providing realistic and varied kinesthetic and tactile feedback to VOs. Many haptic devices have been designed and evaluated specifically for use in \VR, providing realistic and varied kinesthetic and tactile feedback to \VOs.
% %
Although closely related, (visual) AR and VR have key differences in their respective renderings that can affect user perception. Although closely related, (visual) \AR and \VR have key differences in their respective renderings that can affect user perception.
Firstly, the user's hand and RE are visible in AR, unlike VR where there is total control over the visual rendering of the hand and VE. Firstly, the user's hand and \RE are visible in \AR, unlike \VR where there is total control over the visual rendering of the hand and \VE.
% (unless specifically overlaid with virtual visual content) % (unless specifically overlaid with virtual visual content)
% %
As such, in VR, visual sensations are particularly dominant in perception, and conflicts with haptic sensations are also specifically created to influence the user's perception, for example to create pseudo-haptic~\autocite{ujitoko2021survey} or haptic retargeting~\autocite{azmandian2016haptic} effects. As such, in \VR, visual sensations are particularly dominant in perception, and conflicts with haptic sensations are also specifically created to influence the user's perception, for example to create pseudo-haptic~\autocite{ujitoko2021survey} or haptic retargeting~\autocite{azmandian2016haptic} effects.
%enabling techniques such as pseudo-haptic feedback that induce haptic feedback with visual stimuli~\autocite{ujitoko2021survey} or haptic retargeting that associate a single tangible object with multiple VOs without the user noticing~\autocite{azmandian2016haptic}. %enabling techniques such as pseudo-haptic feedback that induce haptic feedback with visual stimuli~\autocite{ujitoko2021survey} or haptic retargeting that associate a single tangible object with multiple \VOs without the user noticing~\autocite{azmandian2016haptic}.
% %
Moreover, many wearable haptic devices take the form of controllers, gloves or exoskeletons, all of which cover the fingertips and are therefore not suitable for AR. Moreover, many wearable haptic devices take the form of controllers, gloves or exoskeletons, all of which cover the fingertips and are therefore not suitable for \AR.
% %
The user's hand must be indeed free to touch and interact with the RE. The user's hand must be indeed free to touch and interact with the \RE.
% %
It is possible instead to place the haptic actuator close to the point of contact with the RE, as described above to implement hAR, \eg providing haptic feedback on another phalanx~\autocite{asano2015vibrotactile,salazar2020altering} or the wrist~\autocite{sarac2022perceived} for rendering fingertip contacts with virtual content. It is possible instead to place the haptic actuator close to the point of contact with the \RE, as described above to implement \hAR, \eg providing haptic feedback on another phalanx~\autocite{asano2015vibrotactile,salazar2020altering} or the wrist~\autocite{sarac2022perceived} for rendering fingertip contacts with virtual content.
% %
Therefore, when touching a virtual or augmented object, the real and virtual visual sensations are seen as colocalised, but the virtual haptic feedback is not. Therefore, when touching a virtual or augmented object, the real and virtual visual sensations are seen as colocalised, but the virtual haptic feedback is not.
% %
It remains to be investigated how such potential discrepancies affect the overall perception to design visuo-haptic renderings adapted to AR. It remains to be investigated how such potential discrepancies affect the overall perception to design visuo-haptic renderings adapted to \AR.
So far, AR can only add visual and haptic sensations to the user's overall perception of the environment, but conversely it is very difficult to remove sensations. So far, \AR can only add visual and haptic sensations to the user's overall perception of the environment, but conversely it is very difficult to remove sensations.
% %
These added virtual sensations can therefore be perceived as out of sync or even inconsistent with the sensations of the RE, for example with a lower rendering quality, a temporal latency, a spatial shift, or a combination of these. These added virtual sensations can therefore be perceived as out of sync or even inconsistent with the sensations of the \RE, for example with a lower rendering quality, a temporal latency, a spatial shift, or a combination of these.
% %
It is therefore unclear to what extent the real and virtual visuo-haptic sensations will be perceived as realistic or plausible, and to what extent they will conflict or complement each other in the perception of the AE. It is therefore unclear to what extent the real and virtual visuo-haptic sensations will be perceived as realistic or plausible, and to what extent they will conflict or complement each other in the perception of the \AE.
% %
%Therefore, it remains to be investigated how these three characteristics of using wearable haptics with AR affect the perception, especially with visually and haptically augmented objects. %Therefore, it remains to be investigated how these three characteristics of using wearable haptics with \AR affect the perception, especially with visually and haptically augmented objects.
% on voit sa propre main toucher, contrairement à la VR, où la vision est particulièrement dominante (eg retargeting), difficile à dire si le cas en RA, surtout que si touche objets augmentés, difficile de modifier visuellement et haptiquement on peut ajouter des sensations pas vraiment en enlever. Lactuateur n'est pas là où on touche, à quel point les sensations seront réalistes ? En cohérence avec les sensations visuelles ? À quel point la perception différente de la VR, en terme de rendu main env, et de latence ? Important car permettra d'utiliser efficacement, avwc correction si besoin par rapport à la VR. Lq boucle d'interaction a forcément de la latence par rapport aux mouvements, à la proprioception, et pas les mêmes entre visuel et haptique, quel effet ? % on voit sa propre main toucher, contrairement à la \VR, où la vision est particulièrement dominante (eg retargeting), difficile à dire si le cas en RA, surtout que si touche objets augmentés, difficile de modifier visuellement et haptiquement on peut ajouter des sensations pas vraiment en enlever. Lactuateur n'est pas là où on touche, à quel point les sensations seront réalistes ? En cohérence avec les sensations visuelles ? À quel point la perception différente de la \VR, en terme de rendu main env, et de latence ? Important car permettra d'utiliser efficacement, avwc correction si besoin par rapport à la \VR. Lq boucle d'interaction a forcément de la latence par rapport aux mouvements, à la proprioception, et pas les mêmes entre visuel et haptique, quel effet ?
\subsectionstarbookmark{Enable Effective Interaction with the Augmented Environment} \subsectionstarbookmark{Enable Effective Interaction with the Augmented Environment}
Touching, grasping and manipulating VOs are fundamental interactions for AR~\autocite{kim2018revisiting}, VR~\autocite{bergstrom2021how} and VEs in general~\autocite{laviola20173d}. Touching, grasping and manipulating \VOs are fundamental interactions for \AR~\autocite{kim2018revisiting}, \VR~\autocite{bergstrom2021how} and VEs in general~\autocite{laviola20173d}.
% %
As the hand is not occupied or covered with a haptic device to not impair interaction with the RE, as described in the previous section, one can expect a a seamless and direct interaction of the hand with the virtual content as if it were real. As the hand is not occupied or covered with a haptic device to not impair interaction with the \RE, as described in the previous section, one can expect a a seamless and direct interaction of the hand with the virtual content as if it were real.
% %
Thus, augmenting a tangible object has the advantage of physically constraining the hand, allowing for easy and natural interaction, but manipulating a purely VO with the bare hand can be challenging without good haptic feedback~\autocite{maisto2017evaluation,meli2018combining}. %, and one will rely on visual and haptic feedback to guide the interaction. Thus, augmenting a tangible object has the advantage of physically constraining the hand, allowing for easy and natural interaction, but manipulating a purely \VO with the bare hand can be challenging without good haptic feedback~\autocite{maisto2017evaluation,meli2018combining}. %, and one will rely on visual and haptic feedback to guide the interaction.
In addition, current AR systems have visual rendering limitations that also affect interaction with VOs. %, due to depth underestimation, a lack of mutual occlusions, and hand tracking latency. In addition, current \AR systems have visual rendering limitations that also affect interaction with \VOs. %, due to depth underestimation, a lack of mutual occlusions, and hand tracking latency.
% %
Visual AR is the display of superimposed images of the virtual world, synchronized with the user's current view of the real world. Visual \AR is the display of superimposed images of the virtual world, synchronized with the user's current view of the real world.
% %
But the depth perception of the VOs is often underestimated~\autocite{peillard2019studying,adams2022depth}, and there is often a lack of mutual occlusion between the hand and a VO, \ie that the hand can hide the object or be hidden by the object~\autocite{macedo2023occlusion}. But the depth perception of the \VOs is often underestimated~\autocite{peillard2019studying,adams2022depth}, and there is often a lack of mutual occlusion between the hand and a \VO, \ie that the hand can hide the object or be hidden by the object~\autocite{macedo2023occlusion}.
% %
Finally, as illustrated in \figref{interaction-loop}, interacting with a VO is an illusion, because in fact the real hand is controlling in real time a virtual hand, like an avatar, whose contacts with VOs are then simulated in the VE. Finally, as illustrated in \figref{interaction-loop}, interacting with a \VO is an illusion, because in fact the real hand is controlling in real time a virtual hand, like an avatar, whose contacts with \VOs are then simulated in the \VE.
% %
Therefore, there is inevitably a latency delay between the real hand's movements and the VO's return movements, and a spatial shift between the real hand and the virtual hand, whose movements are constrained to the touched VO~\autocite{prachyabrued2014visual}. Therefore, there is inevitably a latency delay between the real hand's movements and the \VO's return movements, and a spatial shift between the real hand and the virtual hand, whose movements are constrained to the touched \VO~\autocite{prachyabrued2014visual}.
% %
This makes it difficult to perceive the position of the fingers relative to the object before touching or grasping it, and also to estimate the force required to grasp and move the object to a desired location. This makes it difficult to perceive the position of the fingers relative to the object before touching or grasping it, and also to estimate the force required to grasp and move the object to a desired location.
Hence, it is necessary to provide visual and haptic feedback that allows the user to efficiently contact, grasp and manipulate a VO with the hand. Hence, it is necessary to provide visual and haptic feedback that allows the user to efficiently contact, grasp and manipulate a \VO with the hand.
% %
Yet, it is unclear which type of visual and haptic feedback is the best suited to guide the VO manipulation, and whether one or the other of a combination of the two is most beneficial for users. Yet, it is unclear which type of visual and haptic feedback is the best suited to guide the \VO manipulation, and whether one or the other of a combination of the two is most beneficial for users.
% comme on laisse la main libre, et quelle visible, il n'y a pas de contrôleur tracké comme en VR, donc on s'attend à des interactions naturelles directement avec la main, de manière seamless entre physique et virtuel. On tracking additionel des actuateurs qui couvre la main. Question de où placer lactuateur, encore une fois le feedback n'est pas colocalisé avec l'action, contrairement au visuel (+- lag). Il y a également des décalages dans le temps et l'espace entre la main physique et son replicat virtuel, or c'est ce dernier qui agit avec les objets virtuel, est-ce qu'il faut le montrer ? Ou des rendus haptiques suffisent, complémentaire, en contradiction ? % comme on laisse la main libre, et quelle visible, il n'y a pas de contrôleur tracké comme en \VR, donc on s'attend à des interactions naturelles directement avec la main, de manière seamless entre physique et virtuel. On tracking additionel des actuateurs qui couvre la main. Question de où placer lactuateur, encore une fois le feedback n'est pas colocalisé avec l'action, contrairement au visuel (+- lag). Il y a également des décalages dans le temps et l'espace entre la main physique et son replicat virtuel, or c'est ce dernier qui agit avec les objets virtuel, est-ce qu'il faut le montrer ? Ou des rendus haptiques suffisent, complémentaire, en contradiction ?
\section{Approach and Contributions} \section{Approach and Contributions}
The aim of this thesis is to understand how immersive visual and wearable haptic feedback compare and complement each other in the context of direct hand perception and interaction with augmented and VOs. The aim of this thesis is to understand how immersive visual and wearable haptic feedback compare and complement each other in the context of direct hand perception and interaction with augmented and \VOs.
% %
As described in the Research Challenges section above, providing a convincing, consistent and effective vhAE to a user is complex and raises many issues. As described in the Research Challenges section above, providing a convincing, consistent and effective \vhAE to a user is complex and raises many issues.
% %
Our approach is to Our approach is to
% %
@@ -276,7 +276,7 @@ Our contributions in these two axes are summarized in \figref{contributions}.
\fig[0.95]{contributions}{Summary of our contributions through the simplified interaction loop.}[% \fig[0.95]{contributions}{Summary of our contributions through the simplified interaction loop.}[%
The contributions are represented in dark gray boxes, and the research axes in light green circles. % The contributions are represented in dark gray boxes, and the research axes in light green circles. %
The first (I) axis designs and evaluates the perception of visuo-haptic texture augmentations of tangible surfaces, directly touched by the hand. % The first (I) axis designs and evaluates the perception of visuo-haptic texture augmentations of tangible surfaces, directly touched by the hand. %
The second (II) axis focuses on improving the manipulation of VOs with the bare hand using visuo-haptic augmentations of the hand as interaction feedback.% The second (II) axis focuses on improving the manipulation of \VOs with the bare hand using visuo-haptic augmentations of the hand as interaction feedback.%
] ]
@@ -289,19 +289,19 @@ Our contributions in these two axes are summarized in \figref{contributions}.
% Very short abstract of contrib 2 % Very short abstract of contrib 2
Wearable haptic devices have proven to be effective in modifying the perception of a touched tangible surface, without modifying the tangible, nor covering the fingertip, forming a hAE~\autocite{bau2012revel,detinguy2018enhancing,salazar2020altering}. Wearable haptic devices have proven to be effective in modifying the perception of a touched tangible surface, without modifying the tangible, nor covering the fingertip, forming a \hAE~\autocite{bau2012revel,detinguy2018enhancing,salazar2020altering}.
% %
%It is achieved by placing the haptic actuator close to the fingertip, to let it free to touch the surface, and rendering tactile stimuli timely synchronised with the finger movement. %It is achieved by placing the haptic actuator close to the fingertip, to let it free to touch the surface, and rendering tactile stimuli timely synchronised with the finger movement.
% %
%It enables rich haptic feedback as the combination of kinesthetic sensation from the tangible and cutaneous sensation from the actuator. %It enables rich haptic feedback as the combination of kinesthetic sensation from the tangible and cutaneous sensation from the actuator.
% %
However, wearable hAR have been little explored with visual AR, as well as the visuo-haptic augmentation of textures. However, wearable \hAR have been little explored with visual \AR, as well as the visuo-haptic augmentation of textures.
% %
Texture is indeed one of the main tactile sensation of a surface material~\cite{hollins1993perceptual,okamoto2013psychophysical}, perceived equally well by both sight and touch~\cite{bergmanntiest2007haptic,baumgartner2013visual}, and one of the most studied haptic (only, without visual) rendering~\cite{unger2011roughness,culbertson2014modeling,strohmeier2017generating}. Texture is indeed one of the main tactile sensation of a surface material~\cite{hollins1993perceptual,okamoto2013psychophysical}, perceived equally well by both sight and touch~\cite{bergmanntiest2007haptic,baumgartner2013visual}, and one of the most studied haptic (only, without visual) rendering~\cite{unger2011roughness,culbertson2014modeling,strohmeier2017generating}.
% %
For this first axis of research, we propose to design and evaluate the perception of virtual visuo-haptic textures augmenting tangible surfaces. %, using an immersive AR headset and a wearable vibrotactile device. For this first axis of research, we propose to design and evaluate the perception of virtual visuo-haptic textures augmenting tangible surfaces. %, using an immersive \AR headset and a wearable vibrotactile device.
% %
To this end, we (1) design a system for rendering virtual visuo-haptic texture augmentations, to (2) evaluate how the perception of these textures is affected by the visual virtuality of the hand and the environment (AR \vs VR), and (3) investigate the perception of co-localized visuo-haptic texture augmentations in AR. To this end, we (1) design a system for rendering virtual visuo-haptic texture augmentations, to (2) evaluate how the perception of these textures is affected by the visual virtuality of the hand and the environment (\AR \vs \VR), and (3) investigate the perception of co-localized visuo-haptic texture augmentations in \AR.
First, an effective approach to rendering haptic textures is to generate a vibrotactile signal that represents the finger-texture interaction~\autocite{culbertson2014modeling,asano2015vibrotactile}. First, an effective approach to rendering haptic textures is to generate a vibrotactile signal that represents the finger-texture interaction~\autocite{culbertson2014modeling,asano2015vibrotactile}.
% %
@@ -309,47 +309,47 @@ Yet, to achieve the natural interaction with the hand and a coherent visuo-hapti
% %
Thus, our first objective is to design an immersive, real time system that allows free exploration with the bare hand of visuo-haptic texture augmentations on tangible surfaces. Thus, our first objective is to design an immersive, real time system that allows free exploration with the bare hand of visuo-haptic texture augmentations on tangible surfaces.
Second, many works have investigated the haptic rendering of virtual textures, but few have integrated them with immersive VEs or have considered the influence of the visual rendering on their perception. Second, many works have investigated the haptic rendering of virtual textures, but few have integrated them with immersive \VEs or have considered the influence of the visual rendering on their perception.
% %
Still, it is known that the visual feedback can alter the perception of real and virtual haptic sensations~\autocite{schwind2018touch,choi2021augmenting} but also that the force feedback perception of grounded haptic devices is not the same in AR and VR~\autocite{diluca2011effects,gaffary2017ar}. Still, it is known that the visual feedback can alter the perception of real and virtual haptic sensations~\autocite{schwind2018touch,choi2021augmenting} but also that the force feedback perception of grounded haptic devices is not the same in \AR and \VR~\autocite{diluca2011effects,gaffary2017ar}.
% %
Hence, our second objective is to understand how the perception of haptic texture augmentation differs depending on the degree of visual virtuality of the hand and the environment. Hence, our second objective is to understand how the perception of haptic texture augmentation differs depending on the degree of visual virtuality of the hand and the environment.
Finally, some visuo-haptic texture databases have been modelled from real texture captures~\autocite{culbertson2014penn,balasubramanian2024sens3}, to be rendered as virtual textures with graspable haptics that are perceived as similar to real textures~\autocite{culbertson2015should,friesen2024perceived}. Finally, some visuo-haptic texture databases have been modelled from real texture captures~\autocite{culbertson2014penn,balasubramanian2024sens3}, to be rendered as virtual textures with graspable haptics that are perceived as similar to real textures~\autocite{culbertson2015should,friesen2024perceived}.
% %
However, the rendering of these textures in an immersive and natural visuo-haptic AR using wearable haptics remains to be investigated. However, the rendering of these textures in an immersive and natural visuo-haptic \AR using wearable haptics remains to be investigated.
% %
Our third objective is to evaluate the perception of simultaneous and co-localized visuo-haptic texture augmentation of tangible surfaces in AR, directly touched by the hand, and to understand to what extent each sensory modality contributes to the overall perception of the augmented texture. Our third objective is to evaluate the perception of simultaneous and co-localized visuo-haptic texture augmentation of tangible surfaces in \AR, directly touched by the hand, and to understand to what extent each sensory modality contributes to the overall perception of the augmented texture.
\subsectionstarbookmark{Improving Virtual Object Interaction with Visuo-Haptic Augmentations of the Hand} \subsectionstarbookmark{Improving Virtual Object Interaction with Visuo-Haptic Augmentations of the Hand}
In immersive and wearable visuo-haptic AR, the hand is free to touch and interact seamlessly with real, augmented, and virtual objects, and one can expect natural and direct contact and manipulation of VOs with the bare hand. In immersive and wearable visuo-haptic \AR, the hand is free to touch and interact seamlessly with real, augmented, and virtual objects, and one can expect natural and direct contact and manipulation of \VOs with the bare hand.
% %
However, the intangibility of the vVE, the many display limitations of current visual AR systems and wearable haptic devices, and the potential discrepancies between these two types of feedback can make the interaction with VOs particularly challenging. However, the intangibility of the vVE, the many display limitations of current visual \AR systems and wearable haptic devices, and the potential discrepancies between these two types of feedback can make the interaction with \VOs particularly challenging.
%However, the intangibility of the virtual visual environment, the lack of kinesthetic feedback of wearable haptics, the visual rendering limitations of current AR systems, as well as the spatial and temporal discrepancies between the real environment, the visual feedback, and the haptic feedback, can make the interaction with VOs with bare hands particularly challenging. %However, the intangibility of the virtual visual environment, the lack of kinesthetic feedback of wearable haptics, the visual rendering limitations of current \AR systems, as well as the spatial and temporal discrepancies between the real environment, the visual feedback, and the haptic feedback, can make the interaction with \VOs with bare hands particularly challenging.
% %
Still two types of sensory feedback are known to improve such direct VO interaction, but they have not been studied in combination in immersive vAE: visual rendering of the hand~\autocite{piumsomboon2014graspshell,prachyabrued2014visual} and hand-object interaction rendering with wearable haptics~\autocite{lopes2018adding,teng2021touch}. Still two types of sensory feedback are known to improve such direct \VO interaction, but they have not been studied in combination in immersive \vAE: visual rendering of the hand~\autocite{piumsomboon2014graspshell,prachyabrued2014visual} and hand-object interaction rendering with wearable haptics~\autocite{lopes2018adding,teng2021touch}.
% %
For this second axis of research, we propose to design and evaluate the role of visuo-haptic augmentations of the hand as interaction feedback with VOs. For this second axis of research, we propose to design and evaluate the role of visuo-haptic augmentations of the hand as interaction feedback with \VOs.
% %
We consider (1) the effect of different visual augmentations of the hand as AR avatars and (2) the effect of combination of different visuo-haptic augmentations of the hand. We consider (1) the effect of different visual augmentations of the hand as \AR avatars and (2) the effect of combination of different visuo-haptic augmentations of the hand.
First, the visual rendering of the virtual hand is a key element for interacting and manipulating VOs in VR~\autocite{prachyabrued2014visual,grubert2018effects}. First, the visual rendering of the virtual hand is a key element for interacting and manipulating \VOs in \VR~\autocite{prachyabrued2014visual,grubert2018effects}.
% %
A few works have also investigated the visual rendering of the virtual hand in AR, from simulating mutual occlusions between the hand and VOs~\autocite{piumsomboon2014graspshell,al-kalbani2016analysis} to displaying the virtual hand as an avatar overlay~\autocite{blaga2017usability,yoon2020evaluating}, augmenting the real hand. A few works have also investigated the visual rendering of the virtual hand in \AR, from simulating mutual occlusions between the hand and \VOs~\autocite{piumsomboon2014graspshell,al-kalbani2016analysis} to displaying the virtual hand as an avatar overlay~\autocite{blaga2017usability,yoon2020evaluating}, augmenting the real hand.
% %
But visual AR has significant perceptual differences from VR due to the visibility of the real hand and environment, and these visual hand augmentations have not been evaluated in the context of VO manipulation. But visual \AR has significant perceptual differences from \VR due to the visibility of the real hand and environment, and these visual hand augmentations have not been evaluated in the context of \VO manipulation.
% %
Thus, our fourth objective is to evaluate and compare the effect of different visual hand augmentations on direct manipulation of VOs in AR. Thus, our fourth objective is to evaluate and compare the effect of different visual hand augmentations on direct manipulation of \VOs in \AR.
Finally, as described above, wearable haptics for visual AR rely on moving the haptic actuator away from the fingertips to not impair the hand movements, sensations, and interactions with the RE. Finally, as described above, wearable haptics for visual \AR rely on moving the haptic actuator away from the fingertips to not impair the hand movements, sensations, and interactions with the \RE.
% %
Previous works have shown that wearable haptics that provide feedback on the hand interaction with VOs in AR can significantly improve the user performance and experience~\autocite{maisto2017evaluation,meli2018combining}. Previous works have shown that wearable haptics that provide feedback on the hand interaction with \VOs in \AR can significantly improve the user performance and experience~\autocite{maisto2017evaluation,meli2018combining}.
% %
However, it is unclear which positioning of the actuator is the most beneficial nor how a haptic augmentation of the hand compares or complements with a visual augmentation of the hand. However, it is unclear which positioning of the actuator is the most beneficial nor how a haptic augmentation of the hand compares or complements with a visual augmentation of the hand.
% %
Our last objective is to investigate the role of visuo-haptic augmentations of the hand in manipulating VOs directly with the hand in AR. Our last objective is to investigate the role of visuo-haptic augmentations of the hand in manipulating \VOs directly with the hand in \AR.
\section{Thesis Overview} \section{Thesis Overview}
@@ -362,11 +362,11 @@ This thesis is divided in four parts.
% %
\chapref{related_work} then provides an overview of related work on the perception of and interaction with visual and haptic augmentations of objects. \chapref{related_work} then provides an overview of related work on the perception of and interaction with visual and haptic augmentations of objects.
% %
Firstly, it gives an overview of existing wearable haptic devices and renderings, and how they have been used to enhance the touch perception with haptic augmentations and to improve the VO interaction, with a focus on vibrotactile feedback and haptic textures. Firstly, it gives an overview of existing wearable haptic devices and renderings, and how they have been used to enhance the touch perception with haptic augmentations and to improve the \VO interaction, with a focus on vibrotactile feedback and haptic textures.
% %
Secondly, it introduces the principles and user perception of augmented reality, and describes the 3D interaction techniques used in AR and VR environments to interact with virtual and augmented objects, in particular using the visual rendering of the user's hand. Secondly, it introduces the principles and user perception of augmented reality, and describes the 3D interaction techniques used in \AR and \VR environments to interact with virtual and augmented objects, in particular using the visual rendering of the user's hand.
% %
Finally, it shows how multimodal visuo-haptic feedback has been used in AR and VR to alter the perception of tangible objects and to improve the interaction with VOs. Finally, it shows how multimodal visuo-haptic feedback has been used in \AR and \VR to alter the perception of tangible objects and to improve the interaction with \VOs.
% %
Then, we address each of our two research axes in a dedicated part. Then, we address each of our two research axes in a dedicated part.
@@ -374,21 +374,21 @@ Then, we address each of our two research axes in a dedicated part.
\partref{perception} describes our contributions to the first axis of research, augmenting the visuo-haptic texture perception of tangible surfaces. \partref{perception} describes our contributions to the first axis of research, augmenting the visuo-haptic texture perception of tangible surfaces.
% %
We evaluate how the visual rendering of the hand (real or virtual), the environment (AR or VR) and the textures (displayed or hidden) affect the roughness perception of virtual vibrotactile textures rendered on real surfaces and touched directly with the index finger. We evaluate how the visual rendering of the hand (real or virtual), the environment (\AR or \VR) and the textures (displayed or hidden) affect the roughness perception of virtual vibrotactile textures rendered on real surfaces and touched directly with the index finger.
\chapref{xr_perception} details a system for rendering visuo-haptic virtual textures that augment tangible surfaces using an immersive AR/VR headset and a wearable vibrotactile device. \chapref{xr_perception} details a system for rendering visuo-haptic virtual textures that augment tangible surfaces using an immersive \AR/\VR headset and a wearable vibrotactile device.
% %
The haptic textures are rendered as a real-time vibrotactile signal representing a grating texture, and is provided to the middle phalanx of the index finger touching the texture using a voice-coil actuator (VCA). The haptic textures are rendered as a real-time vibrotactile signal representing a grating texture, and is provided to the middle phalanx of the index finger touching the texture using a voice-coil actuator (VCA).
% %
The tracking of the real hand and environment is done using marker-based technique, and the visual rendering of their virtual counterparts is done using the immersive optical see-through (OST) AR headset Microsoft HoloLens~2. The tracking of the real hand and environment is done using marker-based technique, and the visual rendering of their virtual counterparts is done using the immersive optical see-through (OST) \AR headset Microsoft HoloLens~2.
\chapref{xr_perception} then presents a first user study using this system. \chapref{xr_perception} then presents a first user study using this system.
% %
It evaluates how different the perception of virtual haptic textures is in AR \vs VR and when touched by a virtual hand \vs one's own hand. It evaluates how different the perception of virtual haptic textures is in \AR \vs \VR and when touched by a virtual hand \vs one's own hand.
% %
We use psychophysical methods to measure the user roughness perception of the virtual textures, and extensive questionnaires to understand how this perception is affected by the visual rendering of the hand and the environment. We use psychophysical methods to measure the user roughness perception of the virtual textures, and extensive questionnaires to understand how this perception is affected by the visual rendering of the hand and the environment.
\chapref{ar_textures} presents a second user study using the same system and evaluating the perception of visuo-haptic texture augmentations, touched directly with one's own hand in AR. \chapref{ar_textures} presents a second user study using the same system and evaluating the perception of visuo-haptic texture augmentations, touched directly with one's own hand in \AR.
% %
The textures are paired visual and tactile models of real surfaces~\autocite{culbertson2014one}, and are rendered as visual texture overlays and as a vibrotactile feedback, respectively, on the touched augmented surfaces, respectively. The textures are paired visual and tactile models of real surfaces~\autocite{culbertson2014one}, and are rendered as visual texture overlays and as a vibrotactile feedback, respectively, on the touched augmented surfaces, respectively.
% %
@@ -398,17 +398,17 @@ Our objective is to assess the perceived realism, plausibility and roughness of
\bigskip \bigskip
\partref{manipulation} describes our contributions to the second axis of research, improving VO interaction with visuo-haptic augmentations of the hand. \partref{manipulation} describes our contributions to the second axis of research, improving \VO interaction with visuo-haptic augmentations of the hand.
% %
We evaluate how the visual and haptic augmentation of the hand can improve the interaction with VOs directly with the hand. We evaluate how the visual and haptic augmentation of the hand can improve the interaction with \VOs directly with the hand.
\chapref{visual_hand} explores in a first user study the effect of six visual hand augmentations that provide contact feedback with the VO, as a set of the most popular hand renderings in the AR literature. \chapref{visual_hand} explores in a first user study the effect of six visual hand augmentations that provide contact feedback with the \VO, as a set of the most popular hand renderings in the \AR literature.
% %
Using the OST-AR headset Microsoft HoloLens~2, the user performance and experience are evaluated in two representative manipulation tasks, \ie push-and-slide and grasp-and-place of a VO directly with the hand. Using the OST-\AR headset Microsoft HoloLens~2, the user performance and experience are evaluated in two representative manipulation tasks, \ie push-and-slide and grasp-and-place of a \VO directly with the hand.
\chapref{visuo_haptic_hand} evaluates in a second user study two vibrotactile contact techniques, provided at four different locations on the real hand, as haptic rendering of the hand-object interaction. \chapref{visuo_haptic_hand} evaluates in a second user study two vibrotactile contact techniques, provided at four different locations on the real hand, as haptic rendering of the hand-object interaction.
% %
They are compared to the two most representative visual hand augmentations from the previous study, and the user performance and experience are evaluated within the same OST-AR setup and manipulation tasks. They are compared to the two most representative visual hand augmentations from the previous study, and the user performance and experience are evaluated within the same OST-\AR setup and manipulation tasks.
\bigskip \bigskip

14
4-conclusion/acronyms.tex
View File

@@ -3,17 +3,3 @@
\renewcommand{\glossarysection}[2][]{} % Remove the title of the glossary \renewcommand{\glossarysection}[2][]{} % Remove the title of the glossary
\printnoidxglossary \printnoidxglossary
\begin{description}[font=\normalfont\bfseries]
\item[AR] Augmented Reality
\item[hAR] Haptic Augmented Reality
\item[HMD] Head-Mounted Display
\item[RE, AE, VE] Real/Augmented/Virtual Environment
\item[RV] Reality-Virtuality continuum
\item[vAE, hAE, vhAE] Visual/Haptic/Visuo-Haptic Augmented Environment
\item[VR] Virtual Reality
\item[vRE, hRE, vhRE] Visual/Haptic/Visuo-Haptic Real Environment
\item[vVE, hVE, vhVE] Visual/Haptic/Visuo-Haptic Virtual Environment
\item[VCA] Voice-Coil Actuator
\item[VO] Virtual Object
\end{description}

22
config/acronyms.tex
View File

@@ -27,3 +27,25 @@
\gls{#1}% \gls{#1}%
}% }%
} }
\let\AE\undefined
\acronym{AE}{augmented environment}
\acronym{AR}{augmented reality}
\acronym{hAE}{haptic augmented environment}
\acronym{hAR}{haptic augmented reality}
\acronym{HMD}{head-mounted display}
\acronym{hRE}{haptic real environment}
\acronym{hVE}{haptic virtual environment}
\acronym{MR}{mixed reality}
\acronym{RE}{real environment}
\acronym{RV}{reality-virtuality}
\acronym{vAE}{visual augmented environment}
\acronym{VCA}{voice-coil actuator}
\acronym{VE}{virtual environment}
\acronym{vhAE}{visuo-haptic augmented environment}
\acronym{vhRE}{visuo-haptic real environment}
\acronym{vhVE}{visuo-haptic virtual environment}
\acronym{VO}{virtual object}
\acronym{VR}{virtual reality}
\acronym{vRE}{visual real environment}
\acronym{vVE}{visual virtual environment}