Remove \VO and \AE acronym

3-manipulation/visuo-haptic-hand/1-introduction.tex

@@ -6,22 +6,22 @@ Moreover, it is important to leave the user capable of interacting with both vir
 For this reason, it is often considered beneficial to move the point of application of the haptic feedback elsewhere on the hand (\secref[related_work]{vhar_haptics}).
 However, the impact of the positioning of the haptic feedback on the hand during direct hand manipulation in \AR has not been systematically studied.
 
-Conjointly, a few studies have explored and compared the effects of visual and haptic feedback in tasks involving the manipulation of \VOs with the hand.
+Conjointly, a few studies have explored and compared the effects of visual and haptic feedback in tasks involving the manipulation of virtual objects with the hand.
 \textcite{sarac2022perceived} and \textcite{palmer2022haptic} studied the effects of providing haptic feedback about contacts at the fingertips using haptic devices worn at the wrist, testing different mappings.
 Their results proved that moving the haptic feedback away from the point(s) of contact is possible and effective, and that its impact is more significant when the visual feedback is limited.
 A final question is whether one or the other of these (haptic or visual) hand feedback should be preferred \cite{maisto2017evaluation,meli2018combining}, or whether a combined visuo-haptic feedback is beneficial for users.
 However, these studies were conducted in non-immersive setups, with a screen displaying the \VE view.
-In fact, both hand feedback can provide sufficient sensory feedback for efficient direct hand manipulation of \VOs in \AR, or conversely, they can be shown to be complementary.
+In fact, both hand feedback can provide sufficient sensory feedback for efficient direct hand manipulation of virtual objects in \AR, or conversely, they can be shown to be complementary.
 
-In this chapter, we aim to investigate the role of \textbf{visuo-haptic feedback of the hand when manipulating \VO} in immersive \OST-\AR using wearable vibrotactile haptics.
+In this chapter, we aim to investigate the role of \textbf{visuo-haptic feedback of the hand when manipulating virtual object} in immersive \OST-\AR using wearable vibrotactile haptics.
 We selected \textbf{four different delocalized positionings on the hand} that have been previously proposed in the literature for direct hand interaction in \AR using wearable haptic devices (\secref[related_work]{vhar_haptics}): on the nails, the proximal phalanges, the wrist, and the nails of the opposite hand.
 We focused on vibrotactile feedback, as it is used in most of the wearable haptic devices and has the lowest encumbrance.
 In a \textbf{user study}, using the \OST-\AR headset Microsoft HoloLens~2 and two \ERM vibrotactile motors, we evaluated the effect of the four positionings with \textbf{two contact vibration techniques} on the user performance and experience with the same two manipulation tasks as in \chapref{visual_hand}.
-We additionally compared these vibrotactile renderings with the \textbf{skeleton-like visual hand augmentation} established in the \chapref{visual_hand} as a complementary visuo-haptic feedback of the hand interaction with the \VOs.
+We additionally compared these vibrotactile renderings with the \textbf{skeleton-like visual hand augmentation} established in the \chapref{visual_hand} as a complementary visuo-haptic feedback of the hand interaction with the virtual objects.
 
 \noindentskip The contributions of this chapter are:
 \begin{itemize}
-  \item The evaluation in a user study with 20 participants of the effect of providing a vibrotactile feedback of the fingertip contacts with \VOs, during direct manipulation with bare hand in \AR, at four different delocalized positionings of the haptic feedback on the hand and with two contact vibration techniques.
+  \item The evaluation in a user study with 20 participants of the effect of providing a vibrotactile feedback of the fingertip contacts with virtual objects, during direct manipulation with bare hand in \AR, at four different delocalized positionings of the haptic feedback on the hand and with two contact vibration techniques.
   \item The comparison of these vibrotactile positionings and renderings techniques with the two most representative visual hand augmentations established in the \chapref{visual_hand}.
 \end{itemize}
 

3-manipulation/visuo-haptic-hand/2-method.tex

@@ -1,13 +1,13 @@
 \section{Vibrotactile Renderings of the Hand-Object Contacts}
 \label{vibration}
 
-The vibrotactile hand rendering provided information about the contacts between the \VO and the thumb and index fingers of the user, as they are the two fingers most used for grasping (\secref[related_work]{grasp_types}).
+The vibrotactile hand rendering provided information about the contacts between the virtual object and the thumb and index fingers of the user, as they are the two fingers most used for grasping (\secref[related_work]{grasp_types}).
 We evaluated both the delocalized positioning and the contact vibration technique of the vibrotactile hand rendering.
 
 \subsection{Vibrotactile Positionings}
 \label{positioning}
 
-We considered five different positionings for providing the vibrotactile rendering as feedback of the contacts between the virtual hand and the \VOs, as shown in \figref{method/locations}.
+We considered five different positionings for providing the vibrotactile rendering as feedback of the contacts between the virtual hand and the virtual objects, as shown in \figref{method/locations}.
 They are representative of the most common locations used by wearable haptic devices in \AR to place their end-effector, as found in the literature (\secref[related_work]{vhar_haptics}), as well as other positionings that have been employed for manipulation tasks.
 For each positioning, we used two vibrating actuators, for the thumb and index finger, respectively.
 
@@ -44,7 +44,7 @@ Similarly, we designed the distance vibration technique (Dist) so that interpene
 \section{User Study}
 \label{method}
 
-This user study aims to evaluate whether a visuo-haptic rendering of the hand affects the user performance and experience of manipulation of \VOs with bare hands in \OST-\AR.
+This user study aims to evaluate whether a visuo-haptic rendering of the hand affects the user performance and experience of manipulation of virtual objects with bare hands in \OST-\AR.
 The chosen visuo-haptic hand renderings are the combination of the two most representative visual hand renderings established in the \chapref{visual_hand}, \ie \level{Skeleton} and \level{No Hand}, described in \secref[visual_hand]{hands}, with the two contact vibration techniques provided at the four delocalized positions on the hand described in \secref{vibration}.
 
 \subsection{Experimental Design}

3-manipulation/visuo-haptic-hand/4-discussion.tex

@@ -1,7 +1,7 @@
 \section{Discussion}
 \label{discussion}
 
-We evaluated twenty visuo-haptic renderings of the hand, in the same two \VO manipulation tasks in \AR as in the \chapref{visual_hand}, as the combination of two vibrotactile contact techniques provided at five delocalized positions on the hand with the two most representative visual hand renderings established in the \chapref{visual_hand}.
+We evaluated twenty visuo-haptic renderings of the hand, in the same two virtual object manipulation tasks in \AR as in the \chapref{visual_hand}, as the combination of two vibrotactile contact techniques provided at five delocalized positions on the hand with the two most representative visual hand renderings established in the \chapref{visual_hand}.
 
 In the \level{Push} task, vibrotactile haptic hand rendering has been proven beneficial with the \level{Proximal} positioning, which registered a low completion time, but detrimental with the \level{Fingertips} positioning, which performed worse (\figref{results/Push-CompletionTime-Location-Overall-Means}) than the \level{Proximal} and \level{Opposite} (on the contralateral hand) positionings.
 The cause might be the intensity of vibrations, which many participants found rather strong and possibly distracting when provided at the fingertips.
@@ -33,18 +33,18 @@ Additionally, the \level{Skeleton} rendering was appreciated and perceived as mo
 Participants reported that this visual hand rendering provided good feedback on the status of the hand tracking while being constrained to the cube, and helped with rotation adjustment in both tasks.
 However, many also felt that it was a bit redundant with the vibrotactile hand rendering.
 Indeed, receiving a vibrotactile hand rendering was found by participants as a more accurate and reliable information regarding the contact with the cube than simply seeing the cube and the visual hand reacting to the manipulation.
-This result suggests that providing a visual hand rendering may not be useful during the grasping phase, but may be beneficial prior to contact with the \VO and during position and rotation adjustment, providing valuable information about the hand pose.
+This result suggests that providing a visual hand rendering may not be useful during the grasping phase, but may be beneficial prior to contact with the virtual object and during position and rotation adjustment, providing valuable information about the hand pose.
 It is also worth noting that the improved hand tracking and grasp helper improved the manipulation of the cube with respect to the \chapref{visual_hand}, as shown by the shorter completion time during the \level{Grasp} task.
 This improvement could also be the reason for the smaller differences between the \level{Skeleton} and the \level{None} visual hand renderings in this second experiment.
 
-In summary, the positioning of the vibrotactile haptic rendering of the hand affected on the performance and experience of users manipulating \VOs with their bare hands in \AR.
+In summary, the positioning of the vibrotactile haptic rendering of the hand affected on the performance and experience of users manipulating virtual objects with their bare hands in \AR.
 The closer the vibrotactile hand rendering was to the point of contact, the better it was perceived in terms of effectiveness, usefulness, and realism.
-These subjective appreciations of wearable haptic hand rendering for manipulating \VOs in \AR were also observed by \textcite{maisto2017evaluation} and \textcite{meli2018combining}.
+These subjective appreciations of wearable haptic hand rendering for manipulating virtual objects in \AR were also observed by \textcite{maisto2017evaluation} and \textcite{meli2018combining}.
 However, the best performance was obtained with the farthest positioning on the contralateral hand (\level{Opposite}), which is somewhat surprising.
 This apparent paradox could be explained in two ways.
 On the one hand, participants behave differently when the haptic rendering was given on the fingers (\level{Fingertips} and \level{Proximal}), close to the contact point, with shorter pushes and larger grip apertures.
 This behavior has likely given them a better experience of the tasks and more confidence in their actions, as well as leading to a lower interpenetration/force applied to the cube \cite{pacchierotti2015cutaneous}.
 On the other hand, the unfamiliarity of the contralateral hand positioning (\level{Opposite}) caused participants to spend more time understanding the haptic stimuli, which might have made them more focused on performing the task.
 In terms of the contact vibration technique, the continuous vibration technique on the finger interpenetration (\level{Distance}) did not make a difference to performance, although it provided more information.
-Participants felt that vibration bursts were sufficient (\level{Distance}) to confirm contact with the \VO.
+Participants felt that vibration bursts were sufficient (\level{Distance}) to confirm contact with the virtual object.
 Finally, it was interesting to note that the visual hand rendering was appreciated but felt less necessary when provided together with vibrotactile hand rendering, as the latter was deemed sufficient for acknowledging the contact.

3-manipulation/visuo-haptic-hand/5-conclusion.tex

@@ -1,8 +1,8 @@
 \section{Conclusion}
 \label{conclusion}
 
-In this chapter, we investigated the visuo-haptic feedback of the hand when manipulating \VOs in immersive \OST-\AR using wearable vibrotactile haptic.
-To do so, we provided vibrotactile feedback of the fingertip contacts with \VOs by moving away the haptic actuator that do not cover the inside of the hand: on the nails, the proximal phalanges, the wrist, and the nails of the opposite hand.
+In this chapter, we investigated the visuo-haptic feedback of the hand when manipulating virtual objects in immersive \OST-\AR using wearable vibrotactile haptic.
+To do so, we provided vibrotactile feedback of the fingertip contacts with virtual objects by moving away the haptic actuator that do not cover the inside of the hand: on the nails, the proximal phalanges, the wrist, and the nails of the opposite hand.
 We selected these four different delocalized positions on the hand from the literature for direct hand interaction in \AR using wearable haptic devices.
 In a user study, we compared twenty visuo-haptic feedback of the hand as the combination of two vibrotactile contact techniques, provided at five different delocalized positions on the user's hand, and with the two most representative visual hand augmentations established in the \chapref{visual_hand}, \ie the skeleton hand rendering and no hand rendering.
 
@@ -13,7 +13,7 @@ This study provide evidence that moving away the feedback from the inside of the
 
 If integration with the hand tracking system allows it, and if the task requires it, a haptic ring worn on the middle or proximal phalanx seems preferable.
 However, a wrist-mounted haptic device will be able to provide richer feedback by embedding more diverse haptic actuators with larger bandwidths and maximum amplitudes, while being less obtrusive than a ring.
-Finally, we think that the visual hand augmentation complements the haptic contact rendering well by providing continuous feedback on the hand tracking, and that it can be disabled during the grasping phase to avoid redundancy with the haptic feedback of the contact with the \VO.
+Finally, we think that the visual hand augmentation complements the haptic contact rendering well by providing continuous feedback on the hand tracking, and that it can be disabled during the grasping phase to avoid redundancy with the haptic feedback of the contact with the virtual object.
 
 \noindentskip This work was published in Transactions on Haptics: