Transitions between chapters

3-perception/vhar-system/6-conclusion.tex

@@ -10,6 +10,7 @@ We adapted the 1D sinusoidal grating rendering method, common in the literature
 Our wearable visuo-haptic augmentation system enable any real surface to be augmented with a minimal setup.
 It also allows a free exploration of the textures, as if they were real (\secref[related_work]{ar_presence}), by letting the user view them from different poses and touch them with the bare finger without constraints on hand movements.
 The visual latency we measured is typical of \AR systems, and the haptic latency is below the perceptual detection threshold for vibrotactile rendering.
+
 This system forms the basis of the apparatus for the user studies presented in the next two chapters, which evaluate the user perception of these visuo-haptic texture augmentations.
 
 \noindentskip This work was presented and published at the VRST 2024 conference:

3-perception/vhar-textures/1-introduction.tex

@@ -1,6 +1,9 @@
 \section{Introduction}
 \label{intro}
 
+In the previous chapter, we investigated the role of the visual feedback of the virtual hand and the environment (\AR \vs \VR) on the perception of wearable haptic texture augmentation.
+In this chapter, we explore the perception of wearable visuo-haptic texture augmentation of real surfaces touched directly with the finger in an immersive \AR context and without a virtual hand overlay.
+
 When we look at the surface of an everyday object, we then touch it to confirm or contrast our initial visual impression and to estimate the properties of the object, particularly its texture (\secref[related_work]{visual_haptic_influence}).
 Among the various haptic texture augmentations, data-driven methods allow to capture, model and reproduce the roughness perception of real surfaces when touched by a hand-held stylus (\secref[related_work]{texture_rendering}).
 Databases of visuo-haptic textures have been developed in this way \cite{culbertson2014one,balasubramanian2024sens3}, but they have not yet been explored in an immersive and direct touch context with \AR and wearable haptics.

3-perception/vhar-textures/5-conclusion.tex

@@ -12,6 +12,10 @@ This suggests that \AR visual textures that augments real surfaces can be enhanc
 This paves the way for new \AR applications capable of augmenting a \RE with virtual visuo-haptic textures, such as visuo-haptic painting in artistic or object design context, or viewing and touching virtual objects in a museum or a showroom.
 The latter is illustrated in \figref{experiment/use_case}, where a user applies different visuo-haptic textures to a wall, in an interior design scenario, to compare them visually and by touch.
 
+We instinctively perceive the properties of everyday objects by touching and exploring them, but we essentially interact with them by grasping in order to manipulate them.
+In this first part, we focused on the perception of wearable and immersive virtual textures that augment real surfaces when touched with the fingertip.
+In the next part, we improve the direct manipulation with the hand of virtual object with wearable visuo-haptic interaction feedback.
+
 \noindentskip This work was presented and published at the EuroHaptics 2024 conference:
 
 Erwan Normand, Claudio Pacchierotti, Eric Marchand, and Maud Marchal.

3-perception/xr-perception/1-introduction.tex

@@ -1,6 +1,9 @@
 \section{Introduction}
 \label{intro}
 
+In the previous chapter, we presented a system for augmenting the visuo-haptic texture perception of real surfaces directly touched with the finger, using wearable vibrotactile haptics and an immersive \AR headset.
+In this and the next chapter, we evaluate the user's perception of such wearable haptic texture augmentation under different visual rendering conditions.
+
 Most of the haptic augmentations of real surfaces using with wearable haptic devices, including roughness of textures (\secref[related_work]{texture_rendering}), have been studied without a visual feedback, and none have considered the influence of the visual rendering on their perception or integrated them in \AR and \VR (\secref[related_work]{texture_rendering}).
 Still, it is known that the visual rendering of an object can influence the perception of its haptic properties (\secref[related_work]{visual_haptic_influence}), and that the perception of same haptic force-feedback or vibrotactile rendering can differ between \AR and \VR, probably due to difference in perceived simultaneity between visual and haptic stimuli (\secref[related_work]{ar_vr_haptic}).
 Indeed, in \AR, the user can see their own hand touching, the haptic device worn and the \RE, while in \VR they are hidden by the \VE.

3-perception/xr-perception/6-conclusion.tex

@@ -20,6 +20,9 @@ When designing for wearable haptics or integrating it into \AR/\VR, it seems imp
 %With a better understanding of how visual factors influence the perception of haptically augmented real objects, the many wearable haptic systems that already exist but have not yet been fully explored with \AR can be better applied and new visuo-haptic renderings adapted to \AR can be designed.
 %Finally, a visual hand representation in OST-\AR together with wearable haptics should be avoided until acceptable tracking latencies \are achieved, as was also observed for virtual object interaction with the bare hand \cite{normand2024visuohaptic}.
 
+In the next chapter we present a second user study where we investigate the perception of simultaneous and co-localised visual and haptic texture augmentation.
+We will use the same system presented in \chapref{vhar_system} and a visual rendering condition similar to the \level{Real} condition of this study, in \AR without the virtual hand overlay.
+
 \noindentskip This work was presented and published at the VRST 2024 conference:
 
 Erwan Normand, Claudio Pacchierotti, Eric Marchand, and Maud Marchal.

4-manipulation/visual-hand/5-conclusion.tex

@@ -17,6 +17,10 @@ This study suggests that a \ThreeD visual hand augmentation is important in \AR
 A minimal but detailed rendering of the virtual hand that does not hide the real hand, such as the skeleton rendering we evaluated, seems to be the best compromise between the richness and effectiveness of the feedback.
 %Still, users should be able to choose and adapt the visual hand rendering to their preferences and needs.
 
+In addition to visual augmentation of the hand, direct manipulation of virtual objects with the hand can also benefit from wearable haptic feedback.
+In the next chapter, we explore two wearable vibrotactile contact feedback devices in a user study, located at four positionings on the hand so as to not cover the fingertips.
+We evaluate their effect on user performance and experience in the same manipulation tasks as in this chapter, with the best visual hand augmentation found in this study.
+
 \noindentskip This work was published in Transactions on Haptics:
 
 Erwan Normand, Claudio Pacchierotti, Eric Marchand, and Maud Marchal.

5-conclusion/conclusion.tex

@@ -12,7 +12,7 @@ Wearable haptics can provide rich tactile feedback on virtual objects and augmen
 However, their integration with \AR is still in its infancy and presents many design, technical and human challenges.
 We have structured this thesis around two research axes: \textbf{(I) modifying the visuo-haptic texture perception of real surfaces} and \textbf{(II) improving the manipulation of virtual objects}.
 
-\noindentskip In \partref{perception}, we focused on modifying the perception of wearable and immersive virtual textures that augment real surfaces.
+\noindentskip In \partref{perception}, we focused on the perception of wearable and immersive virtual textures that augment real surfaces.
 Texture is a fundamental property of an object, perceived equally by sight and touch.
 It is also one of the most studied haptic augmentations, but has not yet been integrated into \AR or \VR.
 We \textbf{(1) proposed a wearable visuo-haptic texture augmentation system}, \textbf{(2)} evaluated how the perception of haptic texture augmentations is \textbf{affected by the visual feedback of the virtual hand} and the environment (real, augmented, or virtual), and \textbf{(3)} investigated the \textbf{perception of co-localized visuo-haptic texture augmentations}.