6.1.1 AsymGait

• Name: Asymmetry index for clinical gait analysis based on depth images
• Keywords: Motion analysis, Kinect, Clinical analysis
• Scientific Description: The system uses depth images delivered by the Microsoft Kinect to retrieve the gait cycles first. To this end it is based on a analyzing the knees trajectories instead of the feet to obtain more robust gait event detection. Based on these cycles, the system computes a mean gait cycle model to decrease the effect of noise of the system. Asymmetry is then computed at each frame of the gait cycle as the spatial difference between the left and right parts of the body. This information is computed for each frame of the cycle.
• Functional Description: AsymGait is a software package that works with Microsoft Kinect data, especially depth images, in order to carry-out clinical gait analysis. First it identifies the main gait events using the depth information (footstrike, toe-off) to isolate gait cycles. Then it computes a continuous asymmetry index within the gait cycle. Asymmetry is viewed as a spatial difference between the two sides of the body.
• Authors: Edouard Auvinet, Franck Multon
• Contact: Franck Multon
• Participants: Edouard Auvinet, Franck Multon

6.1.2 Cinematic Viewpoint Generator

• Keyword: 3D animation
• Functional Description: The software, developed as an API, provides a mean to automatically compute a collection of viewpoints over one or two specified geometric entities, in a given 3D scene, at a given time. These viewpoints satisfy classical cinematographic framing conventions and guidelines including different shot scales (from extreme long shot to extreme close-up), different shot angles (internal, external, parallel, apex), and different screen compositions (thirds,fifths, symmetric of di-symmetric). The viewpoints allow to cover the range of possible framings for the specified entities. The computation of such viewpoints relies on a database of framings that are dynamically adapted to the 3D scene by using a manifold parametric representation and guarantee the visibility of the specified entities. The set of viewpoints is also automatically annotated with cinematographic tags such as shot scales, angles, compositions, relative placement of entities, line of interest.
• Authors: Christophe Lino, Emmanuel Badier, Marc Christie
• Contact: Marc Christie
• Participants: Christophe Lino, Emmanuel Badier, Marc Christie
• Partners: Université d'Udine, Université de Nantes

6.1.3 CusToM

• Name: Customizable Toolbox for Musculoskeletal simulation
• Keywords: Biomechanics, Dynamic Analysis, Kinematics, Simulation, Mechanical multi-body systems
• Scientific Description:

  The present toolbox aims at performing a motion analysis thanks to an inverse dynamics method.

  Before performing motion analysis steps, a musculoskeletal model is generated. Its consists of, first, generating the desire anthropometric model thanks to models libraries. The generated model is then kinematical calibrated by using data of a motion capture. The inverse kinematics step, the inverse dynamics step and the muscle forces estimation step are then successively performed from motion capture and external forces data. Two folders and one script are available on the toolbox root. The Main script collects all the different functions of the motion analysis pipeline. The Functions folder contains all functions used in the toolbox. It is necessary to add this folder and all the subfolders to the Matlab path. The Problems folder is used to contain the different study. The user has to create one subfolder for each new study. Once a new musculoskeletal model is used, a new study is necessary. Different files will be automaticaly generated and saved in this folder. All files located on its root are related to the model and are valuable whatever the motion considered. A new folder will be added for each new motion capture. All files located on a folder are only related to this considered motion.

• Functional Description: Inverse kinematics Inverse dynamics Muscle forces estimation External forces prediction
• Publications: hal-02268958, hal-02088913, hal-02109407, hal-01904443, hal-02142288, hal-01988715, hal-01710990
• Contacts: Antoine Muller, Charles Pontonnier, Georges Dumont
• Participants: Antoine Muller, Charles Pontonnier, Georges Dumont, Pierre Puchaud, Anthony Sorel, Claire Livet, Louise Demestre

6.1.4 Directors Lens Motion Builder

• Keywords: Previzualisation, Virtual camera, 3D animation
• Functional Description: Directors Lens Motion Builder is a software plugin for Autodesk's Motion Builder animation tool. This plugin features a novel workflow to rapidly prototype cinematographic sequences in a 3D scene, and is dedicated to the 3D animation and movie previsualization industries. The workflow integrates the automated computation of viewpoints (using the Cinematic Viewpoint Generator) to interactively explore different framings of the scene, proposes means to interactively control framings in the image space, and proposes a technique to automatically retarget a camera trajectory from one scene to another while enforcing visual properties. The tool also proposes to edit the cinematographic sequence and export the animation. The software can be linked to different virtual camera systems available on the market.
• Authors: Emmanuel Badier, Christophe Lino, Marc Christie
• Contact: Marc Christie
• Participants: Christophe Lino, Emmanuel Badier, Marc Christie
• Partner: Université de Rennes 1

6.1.5 Kimea

• Name: Kinect IMprovement for Egronomics Assessment
• Keywords: Biomechanics, Motion analysis, Kinect
• Scientific Description: Kimea consists in correcting skeleton data delivered by a Microsoft Kinect in an ergonomics purpose. Kimea is able to manage most of the occlultations that can occur in real working situation, on workstations. To this end, Kimea relies on a database of examples/poses organized as a graph, in order to replace unreliable body segments reconstruction by poses that have already been measured on real subject. The potential pose candidates are used in an optimization framework.
• Functional Description: Kimea gets Kinect data as input data (skeleton data) and correct most of measurement errors to carry-out ergonomic assessment at workstation.
• Publications: hal-01612939v1, hal-01393066v1, hal-01332716v1, hal-01332711v2, hal-01095084v1
• Authors: Pierre Plantard, Franck Multon, Anne-Sophie Le Pierres, Hubert Shum
• Contact: Franck Multon
• Participants: Franck Multon, Hubert Shum, Pierre Plantard
• Partner: Faurecia

6.1.6 Populate

• Keywords: Behavior modeling, Agent, Scheduling
• Scientific Description:

  The software provides the following functionalities:

  - A high level XML dialect that is dedicated to the description of agents activities in terms of tasks and sub activities that can be combined with different kind of operators: sequential, without order, interlaced. This dialect also enables the description of time and location constraints associated to tasks.

  - An XML dialect that enables the description of agent's personal characteristics.

  - An informed graph describes the topology of the environment as well as the locations where tasks can be performed. A bridge between TopoPlan and Populate has also been designed. It provides an automatic analysis of an informed 3D environment that is used to generate an informed graph compatible with Populate.

  - The generation of a valid task schedule based on the previously mentioned descriptions.

  With a good configuration of agents characteristics (based on statistics), we demonstrated that tasks schedules produced by Populate are representative of human ones. In conjunction with TopoPlan, it has been used to populate a district of Paris as well as imaginary cities with several thousands of pedestrians navigating in real time.

• Functional Description: Populate is a toolkit dedicated to task scheduling under time and space constraints in the field of behavioral animation. It is currently used to populate virtual cities with pedestrian performing different kind of activities implying travels between different locations. However the generic aspect of the algorithm and underlying representations enable its use in a wide range of applications that need to link activity, time and space. The main scheduling algorithm relies on the following inputs: an informed environment description, an activity an agent needs to perform and individual characteristics of this agent. The algorithm produces a valid task schedule compatible with time and spatial constraints imposed by the activity description and the environment. In this task schedule, time intervals relating to travel and task fulfillment are identified and locations where tasks should be performed are automatically selected.
• Contacts: Carl-Johan Jorgensen, Fabrice Lamarche
• Participants: Carl-Johan Jorgensen, Fabrice Lamarche

6.1.7 PyNimation

• Keywords: Moving bodies, 3D animation, Synthetic human
• Scientific Description: PyNimation is a python-based open-source (AGPL) software for editing motion capture data which was initiated because of a lack of open-source software enabling to process different types of motion capture data in a unified way, which typically forces animation pipelines to rely on several commercial software. For instance, motions are captured with a software, retargeted using another one, then edited using a third one, etc. The goal of Pynimation is therefore to bridge the gap in the animation pipeline between motion capture software and final game engines, by handling in a unified way different types of motion capture data, providing standard and novel motion editing solutions, and exporting motion capture data to be compatible with common 3D game engines (e.g., Unity, Unreal). Its goal is also simultaneously to provide support to our research efforts in this area, and it is therefore used, maintained, and extended to progressively include novel motion editing features, as well as to integrate the results of our research projects. At a short term, our goal is to further extend its capabilities and to share it more largely with the animation/research community.
• Functional Description:

  PyNimation is a framework for editing, visualizing and studying skeletal 3D animations, it was more particularly designed to process motion capture data. It stems from the wish to utilize Python’s data science capabilities and ease of use for human motion research.

  In its version 1.0, Pynimation offers the following functionalities, which aim to evolve with the development of the tool : - Import / Export of FBX, BVH, and MVNX animation file formats - Access and modification of skeletal joint transformations, as well as a certain number of functionalities to manipulate these transformations - Basic features for human motion animation (under development, but including e.g. different methods of inverse kinematics, editing filters, etc.). - Interactive visualisation in OpenGL for animations and objects, including the possibility to animate skinned meshes

• Authors: Ludovic Hoyet, Robin Adili, Benjamin Niay, Alberto Jovane
• Contacts: Ludovic Hoyet, Robin Adili

6.1.8 The Theater

• Keywords: 3D animation, Interactive Scenarios
• Functional Description: The Theater is a software framework to develop interactive scenarios in virtual 3D environements. The framework provides means to author and orchestrate 3D character behaviors and simulate them in real-time. The tools provides a basis to build a range of 3D applications, from simple simulations with reactive behaviors, to complex storytelling applications including narrative mechanisms such as flashbacks.
• Contact: Marc Christie
• Participant: Marc Christie

6.2.1 Immerstar Platform

Participants: Georges Dumont, Ronan Gaugne, Anthony Sorel, Richard Kulpa.

With the two platforms of virtual reality, Immersia (http://www.irisa.fr/immersia) and Immermove (http://m2slab.com/index.php/facilities-4), grouped under the name Immerstar, the team has access to high level scientific facilities. This equipment benefits the research teams of the center and has allowed them to extend their local, national and international collaborations. The Immerstar platform is granted by a Inria CPER funding for 2015-2019 that enables important evolutions of the equipment. In 2016, the first technical evolutions have been decided and, in 2017, these evolutions have been implemented. On one side, for Immermove, the addition of a third face to the immersive space, and the extension of the Vicon tracking system have been realized and continued this year with 23 new cameras. And, on the second side, for Immersia, the installation of WQXGA laser projectors with augmented global resolution, of a new tracking system with higher frequency and of new computers for simulation and image generation in 2017. In 2018, a Scale One haptic device has been installed. It allows, as in the CPER proposal, one or two handed haptic feedback in the full space covered by Immersia and possibility of carrying the user. We celebrated the twentieth anniversary of the Immersia platform in November 2019 by inaugurating the new haptic equipment. We proposed scientific presentations and received 150 participants, and visits for support services where we received 50 persons. Based on these support, in 2020, we participated to a PIA3-Equipex+ proposal. This proposal CONTINUUM involves 22 partner, has been succesfully evaluated and will be granted. The CONTINUUM project will create a collaborative research infrastructure of 30 platforms located throughout France, to advance interdisciplinary research based on interaction between computer science and the human and social sciences. Thanks to CONTINUUM, 37 research teams will develop cutting-edge research programs focusing on visualization, immersion, interaction and collaboration, as well as on human perception, cognition and behaviour in virtual/augmented reality, with potential impact on societal issues. CONTINUUM enables a paradigm shift in the way we perceive, interact, and collaborate with complex digital data and digital worlds by putting humans at the center of the data processing workflows. The project will empower scientists, engineers and industry users with a highly interconnected network of high-performance visualization and immersive platforms to observe, manipulate, understand and share digital data, real-time multi-scale simulations, and virtual or augmented experiences. All platforms will feature facilities for remote collaboration with other platforms, as well as mobile equipment that can be lent to users to facilitate onboarding.

7.2.1 Topology-aware Camera Control

Participants: Marc Christie, Amaury Louarn.

Placing and moving virtual cameras in real-time 3D environments is a task that remains complex due to the many requirements which need to be satisfied simultaneously. Beyond the essential features of ensuring visibility and frame composition for one or multiple targets, an ideal camera system should provide designers with tools to create variations in camera placement and motions, and create shots which conform to aesthetic recommendations. In this work, we propose a controllable process that will assist developers and artists in placing cinematographic cameras and camera paths throughout complex virtual environments, a task that was often manually performed until now. With no specification and no previous knowledge on the events, our tool exploits a topological analysis of the environment to capture the potential movements of the agents, highlight linearities and create an abstract skeletal representation of the environment. This representation is then exploited to automatically generate potentially relevant camera positions and trajectories organized in a graph representation with visibility information. At run-time, the system can then efficiently select appropriate cameras and trajectories according to artistic recommendations. We demonstrate the features of the proposed system with realistic game-like environments, highlighting the capacity to analyze a complex environment, generate relevant camera positions and camera tracks, and run efficiently with a range of different camera behaviours (see Figure 4) 38.

7.2.2 An interactive staging-and-shooting solver for virtual cinematography

Participants: Marc Christie, Amaury Louarn.

7.2.3 Deep Learning of Camera Behaviors

Participants: Marc Christie, Xi Wang.

Designing a camera motion controller that has the capacity to move a virtual camera automatically in relation with contents of a 3D animation, in a cinematographic and principled way, is a complex and challenging task. Many cinematographic rules exist, yet practice shows there are significant stylistic variations in how these can be applied. In this paper, we propose an example-driven camera controller which can extract camera behaviors from an example film clip and re-apply the extracted behaviors to a 3D animation, through learning from a collection of camera motions. Our first technical contribution is the design of a low-dimensional cinematic feature space that captures the essence of a film's cinematic characteristics (camera angle and distance, screen composition and character configurations) and which is coupled with a neural network to automatically extract these cinematic characteristics from real film clips. Our second technical contribution is the design of a cascaded deep-learning architecture trained to (i) recognize a variety of camera motion behaviors from the extracted cinematic features, and (ii) predict the future motion of a virtual camera given a character 3D animation. We propose to rely on a Mixture of Experts (MoE) gating+prediction mechanism to ensure that distinct camera behaviors can be learned while ensuring generalization. We demonstrate the features of our approach through experiments that highlight (i) the quality of our cinematic feature extractor (ii) the capacity to learn a range of behaviors through the gating mechanism, and (iii) the ability to generate a variety of camera motions by applying different behaviors extracted from film clips. Such an example-driven approach offers a high level of controllability which opens new possibilities toward a deeper understanding of cinematographic style and enhanced possibilities in exploiting real film data in virtual environments (see Figure 5). The work is a collaboration with the Beijing Film Academy in China and was presented at SIGGRAPH 2020 22.

7.2.4 Efficient Visibility Computation for Camera Control

Participants: Marc Christie, Ludovic Burg.

7.2.5 Relative Pose Estimation and Planar Reconstruction via Superpixel-Driven Multiple Homographies

Participants: Marc Christie, Xi Wang.

7.2.6 Contact Preserving Shape Transfer For Rigging-Free Motion Retargeting

Participants: Franck Multon, Jean Basset.

In 2018, we introduced the idea of context graph to capture the relationship between body parts surfaces and enhance the quality of the motion retargetting problem. Hence, it becomes possible to retarget the motion of a source character to a target one while preserving the topological relationship between body parts surfaces. However this approach implies to strictly satisfy distance constraints between body parts, whereas some of them could be relaxed to preserve naturalness. In 2019, we introduced a new paradigm based on transfering the shape instead of encoding the pose constraints to tackle this problem for isolated poses. In 2020, we extended this approach to handle continuity in motion, and non-human characters.

Hence, in 12, we presented an automatic method that allows to retarget poses from a source to a target character by transferring the shape of the target character onto the desired pose of the source character. By considering shape instead of pose transfer our method allows to better preserve the contextual meaning of the source pose, typically contacts between body parts, than pose-based strategies. To this end, we propose an optimization-based method to deform the source shape in the desired pose using three main energy functions: similarity to the target shape, body part volume preservation, and collision management to preserve existing contacts and prevent penetrations. The results show that our method allows to retarget complex poses with several contacts to different morphologies, and is even able to create new contacts when morphology changes require them, such as increases in body size. To demonstrate the robustness of our approach to different types of shapes, we successfully apply it to basic and dressed human characters as well as wild animal models, without the need to adjust parameters.

7.2.7 Walk Ratio: Perception of an Invariant Parameter of Human Walk on Virtual Characters

Participants: Ludovic Hoyet, Benjamin Niay, Anne-Hélène Olivier, Katja Zibrek.

Synthesizing motions that look realistic and diverse is a challenging task in animation. Therefore, a few generic walking motions are typically used when creating crowds of walking virtual characters, leading to a lack of variations as motions are not necessarily adapted to each and every virtual character's characteristics. While some attempts have been made to create variations, it appears necessary to identify the relevant parameters that influence users' perception of such variations to keep a good trade-off between computational costs and realism. In this context, we investigated 40 the ability of viewers to identify an invariant parameter of human walking named the Walk Ratio (step length to step frequency ratio), which was shown to be specific to each individual and constant for different speeds, but which has never been used to drive animations of virtual characters. To this end, we captured 2 female and 2 male actors walking at different freely chosen speeds, as well as at different combinations of step frequency and step length. We then performed a perceptual study to identify the Walk Ratio that was perceived as the most natural for each actor when animating a virtual character, and compared it to the Walk Ratio freely chosen by the actor during the motion capture session (Figure 6). We found that Walk Ratios chosen by observers were in the range of Walk Ratios measured in the literature, and that participants perceived differences between the Walk Ratios of animated male and female characters, as evidenced in the biomechanical literature. Our results provide new considerations to drive the animation of walking virtual characters using the Walk Ratio as a parameter, and might provide animators with novel means to control the walking speed of characters through simple parameters while retaining the naturalness of the locomotion.

7.2.8 The impact of stylization on face recognition

Participants: Ludovic Hoyet, Franck Multon, Nicolas Olivier.

While digital humans are key aspects of the rapidly evolving areas of virtual reality, gaming, and online communications, many applications would benefit from using digital personalized (stylized) representations of users, as they were shown to highly increase immersion, presence and emotional response. In particular, depending on the target application, one may want to look like a dwarf or an elf in a heroic fantasy world, or like an alien on another planet, in accordance with the style of the narrative. While creating such virtual replicas requires stylization of the user’s features onto the virtual character, no formal study has however been conducted to assess the ability to recognize stylized characters. In collaboration with Hybrid team and InterDigital, we carried-out a perceptual study investigating the effect of the degree of stylization on the ability to recognize an actor, and the subjective acceptability of stylizations 41 (Figure 7). Results show that recognition rates decrease when the degree of stylization increases, while acceptability of the stylization increases. These results provide recommendations to achieve good compromises between stylization and recognition, and pave the way to new stylization methods providing a tradeoff between stylization and recognition of the actor.

7.2.9 Interaction Fields: Sketching Collective Behaviours.

Participants: Marc Christie, Adèle Colas, Ludovic Hoyet, Anne-Hélène Olivier, Katja Zibrek.

Many applications of computer graphics, such as cinema, video games, virtual reality, training scenarios, therapy, or rehabilitation, involve the design of situations where several virtual humans are engaged. In applications where a user is immersed in the virtual environment, the (collective) behavior of these virtual humans must be realistic to improve the user's sense of presence. While expressive behaviour appears to be a crucial aspect as part of the realism, collective behaviours simulated using typical crowd simulation models (e.g., social forces, potential fields, velocity selection, vision-based) usually lack expressiveness and do not allow to capture more subtle scenarios (e.g., a group of agents hiding from the user or blocking his/her way), which require the ability to simulate complex interactions. As subtle and adaptable collective behaviours are not easily modeled, there is therefore a need for more intuitive ways to design such complex scenarios. In this preliminary work 50, conducted in collaboration with Julien Pettré and Claudio Pacchierotti in Rainbow team, we therefore propose a novel approach to sketch such interactions to define collective behaviours. Although other sketch-based approaches exist, these usually focus on goal-oriented path planning, and not on modelling social or collective behaviour. In comparison, we present the concepts of a new approach based on a user-friendly application enabling users to draw target interactions between agents through intuitive vector fields (Figure 8). In the future, our goal is to use this approach to facilitate the design of expressive and collective behaviours. By considering more generic and dynamic situations, we design diversified and subtle interactions, which so far have mostly focused on predefined static scenarios.

7.3.1 Biofidelity in VR

Participants: Simon Hilt, Georges Dumont, Charles Pontonnier.

Virtual environments (VE) and haptic interfaces (HI) tend to be introduced as virtual prototyping tools to assess ergonomic features of workstations. These approaches are cost-effective and convenient since working directly on the Digital Mock-Up -and thus allows low-cost solutions for studying the ergonomics of workstations upstream of the design chain, thanks to the interaction of an operator and a digital mock-up- in a VE is preferable to constructing a physical mock-up in a Real Environment (RE). However it can be usable only if the ergonomic conclusions made from the VE are similar to the ones you would make in the real world. The focus was put on the evaluation of the impact of visual and haptic renderings in terms of biomechanical fidelity for pick-and-place tasks. We developed an original setup 9, enabling to separate the effect of visual and haptic renderings in the scene in order to investigate individual and combined effects of those modes of immersion and interaction on the biomechanical behavior of the subject during the task. We focused particularly on the mixed effects of the renderings on the biomechanical fidelity of the system to simulate pick-and-place tasks. Fourteen subjects performed time-constrained pick-and-place tasks in RE and VE with a real and a virtual, haptic driven object at three different speeds. Motion of the hand and muscles activation of the upper limb were recorded. A questionnaire assessed subjectively discomfort and immersion. The results revealed significant differences between measured indicators in RE and VE and with real and virtual object. Objective and subjective measures indicated higher muscle activity and higher length of the hand trajectories in VE and with HI. Another important element is that no cross effect between haptic and visual rendering was reported. Theses results confirmed that such systems should be used with caution for ergonomics evaluation, especially when investigating postural and muscle quantities as discomfort indicators. The last of this part lies in an experimental setup easily replicable to asses more systematically the biomechanical fidelity of virtual environments for ergonomics purposes 20. Haptic feedback is a way to interact whit the digital Digital Mock-Up but the control of the haptic device may affect the feedback. We proposed to evaluate the biomechanical fidelity of a pick-and-place task interacting with a 6 degrees of freedom HI and a dedicated inertial and viscous friction compensation algorithm. The proposed work shows that for such low masses manipulation in the proposed setup 10, the subjective feeling, obtained by a questionnaire, of the user using the HI do not correspond to the muscle activity. Such a result is fundamental to classify what can be transferred from virtual to real at a biomechanical level. The development of additional algorithms is needed to achieve a higher biomechanical fidelity, i.e. the user feels and undergoes the same constraints as the interaction with the same real object 30.

This work is also included in the PhD Thesis of Simon Hilt, defended December 4th 2020  47.

7.3.2 Avatar and Sense of Embodiment: Studying the Relative Preference Between Appearance, Control and Point of View.

Participants: Rebecca Fribourg, Ludovic Hoyet.

In Virtual Reality, a number of studies have been conducted to assess the influence of avatar appearance, avatar control and user point of view on the Sense of Embodiment (SoE) towards a virtual avatar. However, such studies tend to explore each factor in isolation. This work, conducted in collaboration with Ferran Argelaguet and Anatole Lécuyer in Hybrid team, aims to better understand the inter-relations among these three factors by conducting a subjective matching experiment 17. In the presented experiment (n=40), participants had to match a given “optimal” SoE avatar configuration (realistic avatar, full-body motion capture, first-person point of view), starting by a “minimal” SoE configuration (minimal avatar, no control, third-person point of view), by iteratively increasing the level of each factor. The choices of the participants provide insights about their preferences and perception over the three factors considered. Moreover, the subjective matching procedure was conducted in the context of four different interaction tasks with the goal of covering a wide range of actions an avatar can do in a VE (Figure 11). This work also included a baseline experiment (n=20) which was used to define the number and order of the different levels for each factor, prior to the subjective matching experiment (e.g. different degrees of realism ranging from abstract to personalised avatars for the visual appearance). The results of the subjective matching experiment show that point of view and control levels were consistently increased by users before appearance levels when it comes to enhancing the SoE. Second, several configurations were identified with equivalent SoE as the one felt in the optimal configuration, but vary between the tasks. Taken together, our results provide valuable insights about which factors to prioritize in order to enhance the SoE towards an avatar in different tasks, and about configurations which lead to fulfilling SoE in VE.

7.3.3 Virtual Co-Embodiment: Evaluation of the Sense of Agency while Sharing the Control of a Virtual Body among Two Individuals

Participants: Rebecca Fribourg, Ludovic Hoyet.

 

In this work, conducted in collaboration with Ferran Argelaguet and Anatole Lécuyer in Hybrid team, as well as with Nami Ogawa, Takuji Narumi and Michitaka Hirose from The University of Tokyo (Japan), we introduce a concept called “virtual co-embodiment” 18, which enables users to share their virtual avatar with another entity (e.g., another user, robot, or autonomous agent, see Figure 12). We describe a proof-of-concept in which two users can be immersed from a first-person perspective in a virtual environment and can have complementary levels of control (total, partial, or none) over a shared avatar. In addition, we conducted an experiment to investigate the influence of users' level of control over the shared avatar and prior knowledge of their actions on the users' sense of agency and motor actions. The results showed that participants are good at estimating their real level of control but significantly overestimate their sense of agency when they can anticipate the motion of the avatar. Moreover, participants performed similar body motions regardless of their real control over the avatar. The results also revealed that the internal dimension of the locus of control, which is a personality trait, is negatively correlated with the user's perceived level of control. The combined results unfold a new range of applications in the fields of virtual-reality-based training and collaborative teleoperation, where users would be able to share their virtual body.

7.3.4 Influence of Threat Occurrence and Repeatabilityon the Sense of Embodiment and Threat Response in VR

Participants: Rebecca Fribourg, Ludovic Hoyet.

This work, conducted in collaboration with Ferran Argelaguet and Anatole Lécuyer in Hybrid team, explored the potential impact of threat occurrence and repeatability on users' Sense of Embodiment (SoE) and threat response 37, by exploring the following question: Does virtual threat harm the Virtual Reality experience? (Figure 13). The main findings of our experiment are that the introduction of a threat does not alter users' SoE but might change their behaviour while performing a task after the threat occurrence. In addition, threat repetitions did not show any effect on users' subjective SoE, or subjective and objective responses to threat. Taken together, our results suggest that embodiment studies should expect potential change in participants behaviour while doing a task after a threat was introduced, but that threat introduction and repetition do not seem to impact the subjective measure of the SoE (user responses to questionnaires) nor the objective measure of the SoE (behavioural response to threat towards the virtual body).

7.3.5 Studying the Inter-Relation Between Locomotion Techniques and Embodiment in Virtual Reality

Participants: Diane Dewez, Ludovic Hoyet.

Virtual embodiment and navigation are two topics widely studied in the virtual reality community. Despite the potential inter-relation between embodiment and locomotion, studies on virtual navigation rarely supply users with a virtual representation, while studies on virtual embodiment rarely allow users to virtually navigate. This work 34, conducted in collaboration with Ferran Argelaguet and Anatole Lécuyer in Hybrid team, explores this potential inter-relation by focusing on the two following questions: Does the locomotion technique have an impact on the user's sense of embodiment? Does embodying an avatar have an impact on the user’s preference and performance depending on the locomotion technique? To address these questions, we conducted a user study (N = 60) exploring the relationship between the locomotion technique and the user's sense of embodiment over a virtual avatar seen from a first-person perspective (Figure 14). Three widely used locomotion techniques were evaluated: real walking, walking-in-place and virtual steering. All participants performed four different tasks involving a different awareness of their virtual avatar. Participants also performed the same tasks without being embodied in an avatar. The results show that participants had a comparable sense of embodiment with all techniques when embodied in an avatar, and that the presence or absence of the virtual avatar did not alter their performance while navigating, independently of the technique. Taken together, our results represent a first attempt to qualify the inter-relation between virtual navigation and virtual embodiment, and suggest that the 3D locomotion technique used has little influence on the user's sense of embodiment in VR.

7.3.6 Eye-Gaze Activity in Crowds: Impact of Virtual Reality and Density

Participants: Florian Berton, Ludovic Hoyet, Anne-Hélène Olivier.

When we are walking in crowds, we mainly use visual information to avoid collisions with other pedestrians. Thus, gaze activity should be considered to better understand interactions between people in a crowd. In this work conducted in collaboration with Julien Pettré in Rainbow team, we used Virtual Reality (VR) to facilitate motion and gaze tracking, as well as to accurately control experimental conditions, in order to study the effect of crowd density on eye-gaze behavior 31. Our motivation is to better understand how interaction neighborhood (i.e., the subset of people actually influencing one's locomotion trajectory) changes with density. To this end, we designed two experiments (Figure 15). The first one evaluates the biases introduced by the use of VR on the visual activity when walking among people, by comparing eye-gaze activity while walking in a real and virtual street. We then designed a second experiment where participants walked in a virtual street with different levels of pedestrian density. We demonstrate that gaze fixations are performed at the same frequency despite increases in pedestrian density, while the eyes scan a narrower portion of the street. These results suggest that in such situations walkers focus more on people in front and closer to them. These results provide valuable insights regarding eye-gaze activity during interactions between people in a crowd, and suggest new recommendations in designing more realistic crowd simulations.

7.3.7 Crowd Navigation in VR: exploring haptic rendering of collisions

Participants: Florian Berton, Ludovic Hoyet, Anne-Hélène Olivier.

Virtual reality (VR) is a valuable experimental tool for studying human movement, including the analysis of interactions during locomotion tasks for developing crowd simulation algorithms. However, these studies are generally limited to distant interactions in crowds, due to the difficulty of rendering realistic sensations of collisions in VR. In this work, conducted in collaboration with Julien Pettré and Claudio Pacchierotti in Rainbow team, we explored the use of wearable haptics to render contacts during virtual crowd navigation 13. We focus on the behavioural changes occurring with or without haptic rendering during a navigation task in a dense crowd, as well as on potential after-effects introduced by the use haptic rendering. Our objective is to provide recommendations for designing VR setup to study crowd navigation behaviour. To this end, we designed an experiment (N=23) where participants navigated in a crowded virtual train station without, then with, and then again without haptic feedback of their collisions with virtual characters (Figure 16). Results show that providing haptic feedback improved the overall realism of the interaction, as participants more actively avoided collisions. We also noticed a significant after-effect in the users' behaviour when haptic rendering was once again disabled in the third part of the experiment. Nonetheless, haptic feedback did not have any significant impact on the users' sense of presence and embodiment.

7.3.8 The effect of gender and attractiveness of motion on proximity in virtual reality

Participants: Ludovic Hoyet, Benjamin Niay, Anne-Hélène Olivier, Katja Zibrek.

In human interaction, people will keep different distances from each other depending on their gender. For example, males will stand further away from males and closer to females. Previous studies in virtual reality (VR), where people were interacting with virtual humans, showed a similar result. However, many other variables influence proximity, such as appearance characteristics of the virtual character (e.g., attractiveness, etc.). In this work 29, conducted in collaboration with Julien Pettré in Rainbow team and Rachel Mcdonnell from Trinity College Dublin (Ireland), we focused on proximity to virtual walkers, where gender could be recognised from motion only, since previous studies using point-light displays found walking motion is rich in gender cues. In our experiment, a walking wooden mannequin approached the participant embodied in a virtual avatar using the HTC Vive Pro HMD and controller (Figure 17). The mannequin animation was motion captured from several male and female actors and each motion was displayed individually on the character. Participants used the controller to stop the approaching mannequin when they felt it was uncomfortably close to them. Based on previous work, we hypothesized that proximity will be affected by the gender of the character, but unlike previous research, the gender in our experiment could only be determined from character's motion. We also expected differences in proximity according to the gender of the participant. We additionally expected some motions to be rated more attractive than others and that attractive motions would reduce the proximity measure. Our results show support for the last two assumptions, but no difference in proximity was found according to the gender of the character's motion. Our findings have implications for the design of virtual characters in interactive virtual environments.

7.3.9 Effect of social settings on proxemics during social interactions in real and virtual conditions

Participants: Florian Berton, Ludovic Hoyet, Anne-Hélène Olivier, Katja Zibrek.

The modelling of virtual crowds for major events, such as the Oympics in Paris in 2024, takes into account the global proxemics standards of individuals without questioning the possible variability of these standards according to the space in which the interactions are performed. We know that body interactions (Goffman, 1974) are subject to rules whose variability is, at least in part, cultural (Hall, 1971). Obviously, these proxemics standards also address practical issues such as available space and space occupancy density. Our objective in this study was to understand the conditions which can explain that the discomfort felt and the adaptive behaviour performed differ when the interaction takes place in the same city and in spaces with identical occupancy densities. Especially, we focused on the effect of the social context of the environement. We aim at estimating the extent to which the prospect of attending a sports performance alters sensitivity to the transgression of proxemics norms. An additional objective was to evaluate whether virtual reality can help us to provide new insights in such a social context, where objective measures out-of-the lab are complex to perform. To answer this question, we designed in collaboration with Julien Pettré (Rainbow team) and colleagues in the field of sociology François Le Yondre, Théo Rougant and Tristan Duverne (Univ Rennes II) an experiment (in real context and then in virtual reality) in two different locations: a train station and the surroundings of a stadium before a league 1 football match) but with similar densities 35 (Figure 18). The task performed by a confederate was to walk and stand excessively close to men aged 20 to 40. The individual's behaviour (not conscious of being a subject of the experiment) was observed by ethnography and explanatory interviews were conducted immediately afterwards. This same experiment was carried out in virtual reality conditions on the same type of population, modelling the two spaces and making it possible to acquire more precise and quantifiable data than in real conditions such as distances, travel time and eye fixations. Our results suggest that proxemics norms vary according to the subjective relationship of the individual to the social settings, where discomfort was much higher in the train station than in a sport context. This variation would translate directly into a modulation of bodily sensitivity to the proximity of the body of others. While we were able to show that social norms still exist in VR, our results did not show a main effect of the social settings on participants' sensitivity to the transgression of proxemics norms. From a methodological point of view, explicit interviews make it possible to usefully identify the reasons why virtual reality does not generate the same reactions, although it sometimes provokes the same sensitivity. We discuss our results in the frame of the cross-fertilization between Sociology and VR.

7.3.10 Characterization and Evaluation of Control Laws for Virtual Steering Navigation

Participants: Anne-Hélène Olivier, Hugo Brument.

This work was performed in collaboration with Ferran Argelaguet and Maud Marchal from Hybrid and Rainbow teams 33.

This work aims at investigating the influence of the control law in virtual steering techniques, and in particular the speed update, on users' behaviour while navigating in virtual environments. To this end, we first propose to characterize existing control laws. Then, we designed a user study to evaluate the impact of the control law on users' behaviour and performance in a navigation task. Participants had to perform a virtual slalom while wearing a head-mounted display. They were following three different sinusoidal-like trajectory (with low, medium and high curvature) using a torso-steering navigation technique with three different control laws (constant, linear and adaptive). The adaptive control law, based on the biomechanics of human walking, takes into account the relation between speed and curvature. We propose a spatial and temporal analysis of the trajectories performed both in the virtual and the real environment. The results show that users' trajectories and behaviors were significantly affected by the shape of the trajectory but also by the control law. In particular, users' angular velocity was higher with constant and linear laws compared to the adaptive law. The analysis of subjective feedback suggests that these differences might result in a lower perceived physical demand and effort for the adaptive control law. This works discussed the potential applications of such results to improve the design and evaluation of navigation control laws.

7.3.11 Influence of Dynamic Field of View Restrictions on Rotation Gain Perception in Virtual Environments

Participants: Anne-Hélène Olivier, Hugo Brument.

This work was performed in collaboration with Ferran Argelaguet and Maud Marchal from Hybrid and Rainbow teams 32.

The perception of rotation gain, defined as a modification of the virtual rotation with respect to the real rotation, has been widely studied to determine detection thresholds and widely applied to redirected navigation techniques. In contrast, Field of View (FoV) restrictions have been explored in virtual reality as a mitigation strategy for motion sickness, although they can alter user's perception and navigation performance in virtual environments. This work explores whether the use of dynamic FoV manipulations, referred also as vignetting, could alter the perception of rotation gains during virtual rotations in virtual environments (VEs). We conducted a study to estimate and compare perceptual thresholds of rotation gains while varying the vignetting type (no vignetting, horizontal and global vignetting) and the vignetting effect (luminance or blur) as illustrated on Figure 19. 24 Participants performed 60 or 90 degrees virtual rotations in a virtual forest, with different rotation gains applied. Participants have to choose whether or not the virtual rotation was greater than the physical one. Results showed that the point of subjective equality was different across the vignetting types, but not across the vignetting effect or the turns. Subjective questionnaires indicated that vignetting seems less comfortable than the baseline condition to perform the task. These results open applications to improve the design of vignetting for redirection techniques.

7.4.1 Uncovering EEG Correlates of Covert Attention in Soccer Goalkeepers: Towards Innovative Sport Training Procedures

Participants: Richard Kulpa, Benoit Bideau.

Advances in sports sciences and neurosciences offer new opportunities to design efficient and motivating sport training tools. For instance, using NeuroFeedback (NF), athletes can learn to self-regulate specific brain rhythms and consequently improve their performances. In 21, we focused on soccer goalkeepers’ Covert Visual Spatial Attention (CVSA) abilities, which are essential for these athletes to reach high performances. We looked for Electroencephalography (EEG) markers of CVSA usable for virtual reality-based NF training procedures, i.e., markers that comply with the following criteria: (1) specific to CVSA, (2) detectable in real-time and (3) related to goalkeepers’ performance/expertise. Our results revealed that the best-known EEG marker of CVSA—increased α-power ipsilateral to the attended hemi-field— was not usable since it did not comply with criteria 2 and 3. Nonetheless, we highlighted a significant positive correlation between athletes’ improvement in CVSA abilities and the increase of their α-power at rest. While the specificity of this marker remains to be demonstrated, it complied with both criteria 2 and 3. This result suggests that it may be possible to design innovative ecological training procedures for goalkeepers, for instance using a combination of NF and cognitive tasks performed in virtual reality.

7.4.2 Training team ball sports in VR

Participants: Richard Kulpa, Benoit Bideau, Charles Faure, Annabelle Limballe.

Virtual reality (VR) is a widespread technology drawing an increasing interest for players and coaches, especially in team ball sports as it offers a simple tool to simulate, analyse and train situations that are often too complex to reproduce in the field. In this review 16 we aimed at (1) providing an overview of methodologies and outcomes of research studies using VR in team ball sports; (2) better evaluating the potential interest of VR to analyse or train team ball sports situation and (3) identifying limitations, gaps in knowledge and remaining scientific challenges. The MEDLINE and Web of Science Core Collection databases were searched, using predefined combinations of keywords. Thirty articles were retained and analysed. VR can be an interesting tool to assess or train team ball sports skills/situations as it allows researchers to control and standardise situations and focus on specific skills/subskills. Studies that used VR in team ball sports still have some limitations, mainly due to technical issues or study design. This review was the opportunity to describe how VR should be used to enhance understanding of performance in team ball sports. Additional suggestions for future research and study design were proposed.

7.4.3 Impact of open stance in tennis serve on performance an injury

Participants: Richard Kulpa, Benoit Bideau, Pierre Touzard, Anthony Sorel.

The open stance forehand has been hypothesized to be more traumatic for injuries in tennis than the neutral stance forehand. we worked on the comparison of kinematics and kinetics at the knee) and hip (15) during three common forehand stroke stances (attacking neutral stance ANS, attacking open stance AOS, defensive open stance DOS) to determine if the open stance forehand induces higher loadings and to discuss its potential relationship with given injuries. The results showed that the DOS increased hip joint angles and loading, thus potentially increasing the risk of hip overuse injuries. The DOS-induced hip motion could put players at a higher risk of posterior-superior hip impingement compared with the ANS and AOS. The results also showed that the DOS increases vertical GRF, maximum knee flexion and abduction angles, range of knee flexion-extension, peak of compressive, distractive and medial knee forces, peak of knee abduction and external rotation torques. Consequently, the DOS appears potentially more at risk for given knee injuries.

7.5.1 Motion-based Prediction of External Forces

Participants: Charles Pontonnier, Georges Dumont, Claire Livet, Anthony Sorel, Nicolas Bideau.

We proposed 25 a method to predict the external efforts exerted on a subject during handling tasks, only with a measure of his motion. These efforts are the contacts forces and moments on the ground and on the load carried by the subject. The method is based on a contact model initially developed to predict the ground reaction forces and moments. Discrete contact points are defined on the biomechanical model at the feet and the hands. An optimization technique computes the minimal forces at each of these points satisfying the dynamic equations of the biomechanical model and the load. The method was tested on a set of asymmetric handling tasks performed by 13 subjects and validated using force platforms and an instrumented load. For each task, predictions of the vertical forces obtained a RMSE of about 0.25 N/kg for the feet contacts and below 1 N/kg for the hands contacts. This method enables to quantitatively assess asymmetric handling tasks on the basis of kinetics variables without additional instrumentation such as force sensors and thus improve the ecological aspect of the studied tasks. We evaluated this method 26 on manual material handling (MMH) tasks. From a set of hypothesized contact points between the subject and the environment (ground and load), external forces were calculated as the minimal forces at each contact point while ensuring the dynamics equilibrium. Ground reaction forces and moments (GRF&M) and load contact forces and moments (LCF&M) were computed from motion data alone. With an inverse dynamics method, the predicted data were then used to compute kinetic variables such as back loading. On a cohort of 65 subjects performing MMH tasks, the mean correlation coefficients between predicted and experimentally measured GRF for the vertical, antero-posterior and medio-lateral components were 0.91 (0.08), 0.95 (0.03) and 0.94 (0.08), respectively. The associated RMSE were 0.51 N/kg, 0.22 N/kg and 0.19 N/kg. The correlation coefficient between L5/S1 joint moments computed from predicted and measured data was 0.95 with a RMSE of 14 Nm for the flexion / extension component. This method thus allows the assessment of MMH tasks without force platforms, which increases the ecological aspect of the tasks studied and enables performance of dynamic analyses in real settings outside the laboratory.

7.5.2 Posture Assessment and Subjective Scale Agreement in Picking Tasks with Low Masses

Participants: Franck Multon, Charles Pontonnier, Georges Dumont, Olfa Haj Mahmoud.

This work 44 aims at analyzing the relationship between postural assessment and perceived discomfort for picking tasks with low mass (1kg), involving a wide range of positions/postures. We analyzed the agreement of the different postural scores (mean value, integral value, root mean square value, weighted average time at each RULA level and the % of time per RULA level) with the subjective assessments. The statistical analysis showed no correlation between subjective and postural scores. A few negative correlations were also noticed, especially for time spent at specific levels of postural discomfort compared to subjective feedback. The results showed that the subjective assessment was not correlated with the postural assessment in such low discriminant tasks. Although postural assessment enabled to discriminate the more difficult postures with regard to the experimental conditions, the subjects were unable to report coherent discomfort feedback. This work demonstrates the complexity of modeling the subjective feedback of subjects to report perceived discomfort. Furure works will evaluate how non-linear models could better approximate this feedback.

7.5.3 Generic and specific musculoskeletal models of the french soldier to support its activity

Participants: Charles Pontonnier, Georges Dumont, Nicolas Bideau, Pierre Puchaud, Simon Kirchhofer.

This work aimed at developing generic and specific musculoskeletal representations of the french soldier. Such models are useful to define the biomechanical specificities of a given population and therefore characterize their needs in terms of physical support. More into details, we aimed at developing biomechanical specifications for locomotion (lower limbs) exoskeleton to support the soldier in mission. Soldiers are widely subject to musculoskeletal disorders, with regard to the physical needs to their mission (load, mission length, ...). From an anthrometric database of the french army, containing 122 anatomical information per subject, we were able to create i) representative musculoskeletal models thanks to k-means clustering and geometrical retargeting 28 ii) efficient geometrical scaling rules based on a limited set of measures 45. These results are useful to enable to extend the characterization of this population and to propose relevant exoskeleton architectures with regard to the tasks to assist.

This work is also included in the PhD Thesis of Pierre Puchaud, defended December 10th 2020 48.

7.6.1 Prediction of plausible locomotion using nonlinear kinematic optimization

Participants: Franck Multon, Nils Hareng.

Predicting the locomotion of given anatomical structure is a key problem in many applications, such as anthropometry, sports, or rehabilitation. The challenge consists in selecting a plausible sequence of poses among the inifinite space of possible poses to walk from one footprinyt tto another one, knowing the anatomical structure of the character.

In this work 19, we addressed this problem with a target application in palaeoanthropology. Previous works have been proposed to optimize the relative trajectory of the ankle in the pelvis reference frame with per-frame inverse kinematics to retrieve the joint angles. However, this approach can lead to asymmetrical, non-periodic motion, and does not take the dynamics of the system into account. Dynamic simulation of bipedal gait has mostly been investigated in robotics using optimal control. It generally requires knowledge on the motion pattern (named walking pattern generator) and may lead to unnatural (i.e., robotic) motion. In this article, we proposed to adapt previous works to compute symmetric and periodic plausible gait for a given skeletal model, with a minimal set of hypotheses.

7.6.2 Clinical evaluation of plantar exteroceptive inefficiency: normalisation of plantar quotient

Participants: Anne-Hélène Olivier, Armel Crétual, Carole Puil.

Understanding motor control is essential for clinical applications. In the context of podiatry, it is fundamental to evaluate the contribution of sensory systems on the regulation of posture and gait to diagnose and adapt patient’s treatment. While visual system has been extensively studied, cutaneous afferents, which are at the very core of podiatry, are challenging to evaluate. Several approaches have been proposed to quantify the role of somesthesis plantar information including electric stimulation, anesthesia and foam interposition between ground and feet. Being the easiest to implement, the most common approach is the foam interposition. By recording the Center of Pressure (CoP) movement, authors showed that standing on a foam challenges balance, increasing postural sway and speed. Derivated from these results, clinicians use the Plantar Quotient to evaluate postural control. It is defined as the ratio between the CoP surface area on foam and the CoP surface area on normal ground. It is supposed to be above 100 in healthy people. Using a specific foam named Depron, Foisy and Kapoula proposed the first study which highlighted that patients with plantar exteroceptive inefficiency were more stabilized on foam, with a ratio below 100 percent. However, there is a lack of consensus in the characteristics of the foam used to perform such an evaluation. While there are nearly as much foams as experiments conducted on this ratio, it was shown that foam density as well as its thickness have an impact on posture. Besides, Depron® is not a clinical foam (thermal insulator), and is a single use material. As foam characteristics influence posture, the objective of this project 46 is to quantify the effect of foam on the Plantar Quotient in order to standardize podiatrist practices and allow inter-practitioner follow-up, and a fair comparison between studies. This will bring knowledge on foam impact on standing balance. It will provide information to normalize the use of Plantar Quotient. Being able to identify a plantar exteroceptive inefficiency population would improve the diagnosis and the treatment of patients with postural deficiencies.

7.6.3 Collision Avoidance between Walkers on a Curvilinear Path

Participants: Anne-Hélène Olivier, Armel Crétual, Richard Kulpa, Anthony Sorel.

Navigating crowded community spaces requires interactions with pedestrians that follow rectilinear and curvilinear trajectories. In the case of rectilinear trajectories, it has been shown that the perceived action-opportunities of the walkers might be afforded based on a future distance of closest approach. However, little is known about collision avoidance behaviours when avoiding walkers that follow curvilinear trajectories.

In this project 23 22 participants were immersed in a virtual environment and avoided a virtual human (VH) that followed either a rectilinear path or a curvilinear path with a 5 m or 10 m radius curve at various distances of closest approach as illustrated in Figure 20. For a curvilinear path with a 5 m radius there were significantly more collisions when the VH approached from behind the participant, and significantly more inversions of the initial crossing order when the VH approached from in-front than the control rectilinear path. During each trial, the evolution of the future distance of closest approach showed similarities between rectilinear paths and curvilinear paths with a 10 m radius curve. Overall, with few collisions and few inversions of crossing order we can conclude that participants were capable of predicting future distance of closest approach of virtual walkers that followed curvilinear trajectories. The task was solved with similar avoidance adaptations to those observed for rectilinear interactions. Future work should consider how acceleration is perceived and used during a collision avoidance task.

Cifre Faurecia - Monitoring of gestual efficiency at work

Participant: Franck Multon, Georges Dumont, Charles Pontonnier, Olfa Haj Mahmoud.

This Cifre contract has started in September 2018 for three years and is funding the PhD thesis of Olfa Haj Mamhoud. It consists in designing new methods based on depth cameras to monitor the activity of workers in production lines, compute the potential risk of musculoskeletal disorders, and efficiency compared to reference workers. It raises several fundamental questions, such as adapting previous methods to assess the risk of musculoskeletal disorders, as they generally rely on static poses whereas the worker is performing motion. Based on previous works in the team (previous Cifre PhD thesis of Pierre Plantard) we will provide 30Hz motion capture of the worker, that will enable us to evaluate various time-dependent assessment methods.

We will also explore how to estimate joint forces based and torques on such noisy and low-sampling motion data. We will then define a new assessment method based on these forces and torques.

The Cifre contracts funds the PhD salary and 10K€ per year for the supervision and management of the PhD thesis.

Cifre InterDigitial - Adaptive Avatar Customization for Immersive Experiences

Participant: Franck Multon, Ludovic Hoyet, Nicolas Olivier.

This Cifre contract has started in February 2019 for three years and is funding the PhD thesis of Nicolas Olivier. The aim of the project is to design stylized avatars of users in immersive environment and digital arts such as videogames or cinema.

To this end, we will design a pipeline from motion and shape capture of the user to the simulation of the 3D real-time and stylized avatar. It will take hairs, eyes, face, body shape and motion into account. The key idea is to stylized both appaearance and motion to make avatar better correspond to the style of the movie of immersive experience. We will carry-out perceptual studies to better understand the expectation of the users when controlling stylized avatars, to maximize embodiment. The Cifre contracts funds the PhD salary and 15K€ per year for the supervision and management of the PhD thesis. This contract is also in collaboration with Hybrid team.

Cifre InterDigitial - Learning-Based Human Character Animation Synthesis for Content Production

Participant: Ludovic Hoyet, Lucas Mourot.

The overall objective of the PhD thesis of Lucas Mourot, which started in June 2020, is to adapt and improve the state-of-art on video animation and human motion modelling to develop a semi-automated framework for human animation synthesis that brings real benefits to artists in the movie and advertising industry. In particular, one objective is to leverage the use of novel learning-based approaches, in order to propose skeleton-based animation representations, as well as editing tools, in order to improve the resolution and accuracy of the produced animations, so that automatically synthetized animations might become usable in an interactive way by animation artists.

Collaboration with company SolidAnim (Bordeaux, France)

Participant: Marc Christie, Xi Wang.

This contract started in November 2019 for three years. Its purpose is to explore novel means of performing depth detection for augmented reality applied to the film and broadcast industries. The grant serves to fund the PhD of Xi Wang. (160kE)

Collaboration Unreal company (Unreal Megagrant)

Participant: Marc Christie.

This contract started in September 2020 for two years. The objective is to explore means of designing novel VR manipulators for character animation tasks in Unreal Engine. (70kE)

9.1.1 Inria associate team not involved in an IIL

9.2.1 FP7 & H2020 Projects

9.3.1 PIA

The Priority Research Program (PPR) "Sport de très haute performance" (STHP) was set up in preparation for the 2024 Paris Olympic and Paralympic Games. It mobilizes the scientific community to meet the needs of high-performance athletes in order to achieve the highest possible performance. With a budget of 20 million euros, it is financed by the Future Investment Program and scientifically steered by the CNRS. In this call, the 2 projects we led were founded among the 6 nationally selected:

• Tennis is a sport with high medal potential at the Olympic and Paralympic Games (JOP) with 9 events on the program (men's and women's singles, men's and women's doubles and mixed, the latter only for able-bodied athletes). France is in the top 3 countries with the most medals in tennis at the Games since 1988. The aim of the BEST - TENNIS project is to optimize the service and return of service performance of the French Tennis Federation's players (able-bodied and wheelchair) through a systemic approach, capitalizing on biomechanical, clinical and cognitive data that will be made available to coaches and athletes through dedicated tools.
• Virtual reality offers a range of stimuli that go beyond the limits of reality, such as facing an opponent with extraordinary abilities or experiencing an action (with visual, auditory and haptic perceptions in an immersive context) that has not yet been mastered. The REVEA project, supported by the Athletics, Boxing and Gymnastics federations, aims to meet the needs of athletes and coaches by exploiting the unique properties of virtual reality to improve athletes' motor performance through the optimization of the underlying perceptual-motor and cognitive-motor processes, while potentially reducing the risk of injuries related to training overload.

9.3.2 ANR

9.3.3 National scientific collaborations

9.3.4 Chaire Safran-Saint-Cyr "the enhanced soldier in the digital battlefield"

Participants: Charles Pontonnier, Pierre Puchaud.

9.3.5 AUTOMA-PIED

Participants: Anne-Hélène Olivier, Armel Crétual , Anthony Sorel.

9.3.6 Défi Avatar

Participants: Jean Basset, Diane Dewez, Rebecca Fribourg, Ludovic Hoyet, Franck Multon.

This project aims at design avatars (i.e., the user’s representation in virtual environments) that are better embodied, more interactive and more social, through improving all the pipeline related to avatars, from acquisition and simulation, to designing novel interaction paradigms and multi-sensory feedback. It involves 6 Inria teams (GraphDeco, Hybrid, Loki, MimeTIC, Morpheo, Potioc), Prof. Mel Slater (Uni. Barcelona), and 2 industrial partners (InterDigitak and Faurecia).

Website: http://avatar.inria.fr

9.4.1 Kimea Cloud

Participants: Franck Multon, Adnane Boukhayma, Shubhendu Jena.

This project is funded by the Bretagne council and BPI France to develeop a new posture assessment system for egonomics analysis. The project is leaded by the Moovency start-up, in collaboration with SME Quortex (for efficient cloud computing) and Inria (for RGB-based 3D pose reconstruction). The key idea is to design a method capable of measuring the 3D joint angles of a character filmed with a simple smartphone in an industry, using an efficient cloud computing architecture and innovative computer vision methods. The project started in November 2020 for 18 months.

10.1.1 Scientific events: organisation

10.1.2 Scientific events: selection

10.1.3 Journal

10.1.4 Invited talks

• Franck Multon was invited speaker in the Laval Virtual Days on Sports, 17/09/2020
• Charles Pontonnier was invited speaker at CC seminar, G-SCOP lab (Grenoble), 28/04/2020
• Adnane Boukhayma was invited speaker at the CRDH Workshop at the IEEE AIVR Conference, 16/12/2020

10.1.5 Scientific expertise

• Franck Multon was scientific experts for the bi-national evaluation of researchers from UGE (former IFSTTAR) in Lyon
• Franck Multon was international scientific expert for the Fonds de recherche du Québec - Santé (FRQS Canada) for the Fondation canadienne pour l’innovation (FCI) call
• Franck Multon was scientific expert for the Region Normandie/ANR joint call

10.1.6 Research administration

• Ludovic Hoyet is the coordinator of the Inria Research Challenge Avatar
• Franck Multon is responsible for the coordination of national Inria actions in Sports
• Franck Multon is the scientific representative of Inria in Sciences2024 group and scientific Committee
• Franck Multon is the scientific representative of Inria in the EUR Digisport steering committe and scientific committee
• Franck Multon is member of the Brittany commission of deontology
• Armel Crétual is the elected head of the Sports Sciences departement (STAPS) in University Rennes2
• Benoit Bideau is the head of the M2S Laboratory
• Benoit Bideau is vice-president of University Rennes2, in charge of the valorisation

Teaching

• Master : Franck Multon, co-leader of the IEAP Master (1 and 2) "Ingénierie et Ergonomie de l'Activité Physique", STAPS, University Rennes2, France
• Master : Franck Multon, "Santé et Performance au Travail : étude de cas", leader of the module, 30H, Master 1 M2S, University Rennes2, France
• Master : Franck Multon, "Analyse Biomécanique de la Performance Motrice", leader of the module, 30H, Master 1 M2S, University Rennes2, France
• Master: Charles Pontonnier, leader of the first year of master "Ingénierie des systèmes complexes", mechatronics, Ecole normale supérieur de Rennes, France
• Master: Charles Pontonnier, Responsible of the internships of students (L3 and M1 "Ingénierie des systèmes complexes"), 15H, Ecole Normale Supérieure de Rennes, France
• Master: Charles Pontonnier, "Numerical simulation of polyarticulated systems", leader of the module, 22H, M1 Mechatronics, Ecole Normale Supérieure de Rennes, France
• Master: Charles Pontonnier, Research projects, 20H, Ecole Normale Supérieure de Rennes, France
• Master : Georges Dumont, Responsible of the second year of the master Engineering of complex systems, École Normale Supérieure de Rennes and Rennes 1 University, France
• Master : Georges Dumont, Mechanical simulation in Virtual reality, 36H, Master Engineering of complex systems and Mechatronics, Rennes 1 University and École Normale Supérieure de Rennes, France
• Master : Georges Dumont, Mechanics of deformable systems, 40H, Master, École Normale Supérieure de Rennes, France
• Master : Georges Dumont, oral preparation to agregation competitive exam, 20H, Master, École Normale Supérieure de Rennes, France
• Master : Georges Dumont, Vibrations in Mechanics, 10H, Master, École Normale Supérieure de Rennes, France
• Master : Georges Dumont, Finite Element method, 12H, Master, École Normale Supérieure de Rennes, France
• Master : Ludovic Hoyet, Computer Graphics, 12h, Ecole Normale Supérieure de Rennes, France
• Master : Ludovic Hoyet, Motion Analysis and Gesture Recognition, 12h, INSA Rennes, France
• Master : Ludovic Hoyet, Réalité Virtuelle pour l'Analyse Ergonomique, Master Ingénierie et Ergonomie des Activités Physique, 21h, University Rennes 2, France
• Master : Anne-Hélène Olivier, co-leader of the APPCM Master (1 and 2) "Activités Physiques et Pathologies Chroniques et Motrices", STAPS, University Rennes2, France
• Master : Anne-Hélène Olivier, "Biostatstiques", 21H, Master 2 APPCM/IEAP, University Rennes2, France
• Master : Anne-Hélène Olivier, "Evaluation fonctionnelle des pathologies motrices", 3H Master 2 APPCM, University Rennes2, France
• Master : Anne-Hélène Olivier, "Maladie neurodégénératives : aspects biomécaniques", 2H Master 1 APPCM, University Rennes2, France
• Master : Anne-Hélène Olivier, "Biostatstiques", 7H, Master 1 EOPS, University Rennes2, France
• Master : Anne-Hélène Olivier, "Méthodologie", 10H, Master 1 IEAP/APPCM, University Rennes2, France
• Master : Anne-Hélène Olivier, "Contrôle moteur : Boucle perceptivo-motrice", 3H, Master 1IEAP, Université Rennes 2, France
• Master: Fabrice Lamarche, "Compilation pour l'image numérique", 29h, Master 1, ESIR, University of Rennes 1, France
• Master: Fabrice Lamarche, "Synthèse d'images", 12h, Master 1, ESIR, University of Rennes 1, France
• Master: Fabrice Lamarche, "Synthèse d'images avancée", 28h, Master 1, ESIR, University of Rennes 1, France
• Master: Fabrice Lamarche, "Modélisation Animation Rendu", 36h, Master 2, ISTIC, University of Rennes 1, France
• Master: Fabrice Lamarche, "Jeux vidéo", 26h, Master 2, ESIR, University of Rennes 1, France
• Master: Fabrice Lamarche, "Motion for Animation and Robotics", 9h, Master 2 SIF, ISTIC, University of Rennes 1, France.
• Master : Armel Crétual, "Méthodologie", leader of the module, 20H, Master 1 M2S, University Rennes2, France
• Master : Armel Crétual, "Biostatstiques", leader of the module, 30H, Master 2 M2S, University Rennes2, France
• Master : Richard Kulpa, "Boucle analyse-modélisation-simulation du mouvement", 27h, leader of the module, Master 2, Université Rennes 2, France
• Master : Richard Kulpa, "Méthodes numériques d'analyse du geste", 27h, leader of the module, Master 2, Université Rennes 2, France
• Master : Richard Kulpa, "Cinématique inverse", 3h, leader of the module, Master 2, Université Rennes 2, France
• Master: Marc Christie, "Multimedia Mobile", Master 2, leader of the module, 32h, Computer Science, University of Rennes 1, France
• Master: Marc Christie, "Projet Industriel Transverse", Master 2, 32h, leader of the module, Computer Science, University of Rennes 1, France
• Master: Marc Christie, "Modelistion Animation Rendu", Master 2, 16h, leader of the module, Computer Science, University of Rennes 1, France
• Master: Marc Christie, "Advanced Computer Graphics", Master 1, 10h, leader of the module, Computer Science, ENS, France
• Licence : Franck Multon, "Ergonomie du poste de travail", Licence STAPS L2 & L3, University Rennes2, France
• Licence: Charles Pontonnier, "Lagrangian Mechanics" , leader of the module, 22H, M2 Mechatronics, Ecole Normale Supérieure de Rennes, France
• Licence: Charles Pontonnier, "Serial Robotics", leader of the module, 24H, L3 Mechatronics, Ecole Normale Supérieure de Rennes, France
• Licence : Anne-Hélène Olivier, "Analyse cinématique du mouvement", 100H , Licence 1, University Rennes 2, France
• Licence : Anne-Hélène Olivier, "Anatomie fonctionnelle", 7H , Licence 1, University Rennes 2, France
• Licence : Anne-Hélène Olivier, "Effort et efficience", 12H , Licence 2, University Rennes 2, France
• Licence : Anne-Hélène Olivier, "Locomotion et handicap", 12H , Licence 3, University Rennes 2, France
• Licence : Anne-Hélène Olivier, "Biomécanique spécifique aux APA", 8H , Licence 3, University Rennes 2, France
• Licence : Anne-Hélène Olivier, "Biomécanique du viellissement", 12H , Licence 3, University Rennes 2, France
• Licence: Fabrice Lamarche, "Initiation à l'algorithmique et à la programmation", 56h, License 3, ESIR, University of Rennes 1, France
• License: Fabrice Lamarche, "Programmation en C++", 46h, License 3, ESIR, University of Rennes 1, France
• Licence: Fabrice Lamarche, "IMA", 24h, License 3, ENS Rennes, ISTIC, University of Rennes 1, France
• Licence : Armel Crétual, "Analyse cinématique du mouvement", 100H, Licence 1, University Rennes 2, France
• Licence : Richard Kulpa, "Biomécanique (dynamique en translation et rotation)", 48h, Licence 2, Université Rennes 2, France
• Licence : Richard Kulpa, "Méthodes numériques d'analyse du geste", 48h, Licence 3, Université Rennes 2, France
• Licence : Richard Kulpa, "Statistiques et informatique", 15h, Licence 3, Université Rennes 2, France

Supervision

• PhD (beginning September 2017, defended December 9th 2020): Pierre Puchaud, Développement d’un modèle musculo-squelettique générique du soldat en vue du support de son activité physique, Ecole normale supérieure, Charles Pontonnier & Nicolas Bideau & Georges Dumont
• PhD (beginning September 2017, defended December 4th 2020): Simon Hilt, Haptique Biofidèle pour l’Interaction en réalité virtuelle, Ecole normale supérieure, Georges Dumont, Charles Pontonnier
• PhD (beginning Sept 2017, defended November 4th 2020) Rebecca Fribourg, Enhancing Avatars in Virtual Reality through Control, Interactions and Feedback, Ferran Argelaguet (Hybrid team), Ludovic Hoyet, Anatole Lécuyer (Hybrid team).
• PhD (beginning November 2017, defended December 14th 2020) Florian Berton, Design of a virtual reality platform for studying immersion and behaviours in aggressive crowds, Nov. 2017, Ludovic Hoyet, Anne-Hélène Olivier, Julien Pettré (Rainbow team).
• PhD in progress (beginning January 2019): Nils Hareng, simulation of plausible bipedal locomotion of human and non-human primate, University Rennes2, Franck Multon, & Bruno Watier (CNRS LAAS in Toulouse)
• PhD in progress (beginning January 2019): Nicolas Olivier, Adaptive Avatar Customization for Immersive Experience, Cifre InterDigital, Franck Multon, Ferran Arguelaget (Hybrid team), Quentin Avril (InterDigital), Fabien Danieau (InterDigital)
• PhD in progress (beginning September 2017): Lyse Leclerc, Intérêts dans les activités physiques du rétablissement de la fonction inertielle des membres supérieurs en cas d’amputation ou d’atrophie, Armel Crétual, Diane Haering
• PhD in progress (beginning September 2018) : Jean Basset, Learning Morphologically Plausible Pose Transfer, Inria, Edmond Boyer (Morpheo Inria Grenoble), Franck Multon
• PhD in progress (beginning September 2018): Olfa Haj Mamhoud, Monitoring de l’efficience gestuelle d’opérateurs sur postes de travail, University Rennes 2, Franck Multon, Georges Dumont, Charles Pontonnier
• PhD in progress (beginning December 2020): Mohamed Younes, Learning and simulating strategies in sports for VR training, University Rennes1, Franck Multon, Richard Kulpa, Ewa Kijak, Simon Malinowski
• PhD in progress (beginning September 2019) : Claire Livet, Dynamique contrainte pour l'analyse musculo-squelettique en temps rapide : vers des méthodes alternatives d'estimation des forces musculaires mises en jeu dans le mouvement humain, Ecole normale supérieure, Georges Dumont, Charles Pontonnier
• PhD in progress (beginning september 2019) : Louise Demestre, simulation MUsculo-squelettique et Structure Elastique pour le Sport (MUSES), Ecole normale supérieure, Georges Dumont, Charles Pontonnier, Nicolas Bideau, Guillaume Nicolas
• PhD in progress: Diane Dewez, Avatar-Based Interaction in Virtual Reality, Oct. 2018, Ferran Argelaguet (Hybrid team), Ludovic Hoyet, Anatole Lécuyer (Hybrid team).
• PhD in progress (beginning Oct 2018): Benjamin Niay, A framework for synthezing personalised human motions from motion capture data and perceptual information, Ludovic Hoyet, Anne-Hélène Olivier, Julien Pettré (Rainbow team).
• PhD in progress (beginning Sept 2019): Alberto Jovane, Modélisation de mouvements réactifs et comportements non verbaux pour la création d’acteurs digitaux pour la réalité virtuelle, Marc Christie, Ludovic Hoyet, Claudio Pacchierotti (Rainbow team), Julien Pettré (Rainbow team).
• PhD in progress (beginning Nov 2019): Adèle Colas, Modélisation de comportements collectifs réactifs et expressifs pour la réalité virtuelle, Ludovic Hoyet, Anne-Hélène Olivier, Claudio Pacchierotti (Rainbow team), Julien Pettré (Rainbow team).
• PhD in progress (beginning Oct 2018) Hugo Brument, Toward user-adapted interactions techniques based on human locomotion laws for navigating in virtual environments, Anne-Hélène Olivier, Ferran Argelaguet (Hybrid team), Maud Marchal (Rainbow team).
• PhD in progress: Lyse Leclercq, Intérêts dans les activités physiques du rétablissement de la fonction inertielle des membres supérieurs en cas d’amputation ou d’atrophie, Sep. 2017, Armel Crétual, Diane Haering
• PhD in progress: Florence Gaillard, Validation d’un protocole d’analyse 3D du mouvement des membres supérieurs en situation écologique chez les enfants ayant une Hémiplégie Cérébrale Infantile, Armel Crétual, Isabelle Bonan
• PhD in progress: Karim Jamal, Effets des stimulations sensorielles par vibration des muscles du cou sur les perturbations posturales secondaires aux troubles de la représentation spatiale après un accident vasculaire cérébral, Sep 2016, Isabelle Bonan, Armel Crétual
• PhD in progress (beginning Sep 2018): Carole Puil, Impact d’une stimulation plantaire orthétique sur la posture d’individus sains et posturalement déficients au cours de la station debout, et lors de la marche, Armel Crétual, Anne-Hélène Olivier
• PhD in progress: Théo Perrin, Evaluation de la perception de l'effort en réalité virtuelle pour l'entraînement sportif, Sep. 2017, Richard Kulpa, Benoit Bideau
• PhD in progress: Annabelle Limballe, Anticipation dans les sports de combat : la réalité virtuelle comme solution innovante d’entraînement, Sep. 2019, Richard Kulpa & Benoit Bideau
• PhD in progress: Alexandre Vu, Evaluation de l’influence des feedbacks sur la capacité d’apprentissage dans le cadre d’interactions complexes entre joueurs et influence de ces feedbacks en fonction de l’activité sportive , Sep. 2019, Richard Kulpa & Benoit Bideau
• PhD in Progress (beginning December 2020): Qian Li, Synthèse neurale de nouvelles vues de personnes dynamiques dans des videos monoculaires, University Rennes1, Franck Multon, Adnane Boukhayma
• PhD in progress (beginning September 2020): Pauline Morin, Adaptation des méthodes prédiction des efforts d’interaction pour l’analyse biomécanique du mouvement en milieu écologique, Ecole normale supérieure de Rennes, direction Georges Dumont et Charles Pontonnier
• PhD in progress (beginning June 2020): Lucas Mourot, Learning-Based Human Character Animation Synthesis for Content Production, Pierre Hellier (InterDigital), Ludovic Hoyet, Franck Multon, François Le Clerc (InterDigital).
• PhD in progress (beginning September 2020): Agathe Bilhaut, Stratégies perceptivo-motrices durant la locomotion des patients douloureux chroniques : nouvelles méthodes d’analyse et de suivi, Armel Crétual, Anne-Hélène Olivier, Mathieu Ménard (Institut Ostéopathie Rennes, M2S)
• PhD in progress (beginning October 2020): Emilie Leblong, Prise en compte des interactions sociales dans un simulateur de conduite de fauteuil roulant électrique en réalité virtuelle : favoriser l’apprentissage pour une mobilité inclusive, Anne-Hélène Olivier, Marie Babel (Rainbow team)
• PhD in progress (beginning October 2020): Raphaël Dang-Nhu, Learning and evaluating 3D human motion synthesis, Anne-Hélène Olivier, Stefanie Wuhrer (Morpheo team)
• PhD in progress (beginning November 2020): Thomas Chatagnon, Micro-to-macro energy-based interaction models for dense crowds behavioral simulations, Ecole normale supérieure de Rennes, Ludovic Hoyet, Anne-Hélène Olivier,Charles Pontonnier, Julien Pettré (Rainbow team).
• PhD in progress (beginning November 2020): Vicenzo Abichequer-Sangalli, Humains virtuels expressifs et réactifs pour la réalité virtuelle, Marc Christie, Ludovic Hoyet, Carol O'Sullivan (TCD, Ireland), Julien Pettré (Rainbow team).
• PhD in progress (beginning November 2020): Tairan Yin, Création de scènes peuplées dynamiques pour la réalité virtuelle, Marc Christie, Marie-Paule Cani (LIX), Ludovic Hoyet, Julien Pettré (Rainbow team).
• PhD in progress (beginning October 2020): Qian Li, Neural novel view synthesis of dynamic people from monocular videos, Adnane Boukhayma, Franck Multon.

Juries

• PhD defense: Tel Aviv University, Kfir Aberman, " Learning the Structure of Motion", October 2020. Franck Multon, Reviewer
• PhD defense: Toulouse University, Thibault Blanc-Beyne, "Estimation de posture 3D à partir de données imprécises et incomplètes : application à l’analyse d’activité d’opérateurs humains dans un centre de tri", Décember 2020. Franck Multon, Reviewer
• PhD defense: Lille University, Nadia Hosni, "From functional PCA to Convolutional Deep AE on Kendall’s Shape Trajectories for 3D Gait Analysis and Recognition", november 2020, Franck Multon, Examiner

10.2.1 Internal or external Inria responsibilities

Franck Multon coordinated national actions of Inria in Sports.

International journals

• 11 articleJean-BaptisteJ.-B. Barreau, RonanR. Gaugne, Anne-HélèneA.-H. Olivier, SylvianeS. Llinares and ValérieV. Gouranton. A reconstruction of life on a East India Company ship in the 18th centuryIn Situ : Revue des patrimoines42422020, 1-17
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• 12 articleJeanJ. Basset, StefanieS. Wuhrer, EdmondE. Boyer and FranckF. Multon. Contact preserving shape transfer: Retargeting motion from one shape to anotherComputers and Graphics892020, 11-23
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• 13 articleFlorianF. Berton, FabienF. Grzeskowiak, AlexandreA. Bonneau, AlbertoA. Jovane, MarcoM. Aggravi, LudovicL. Hoyet, Anne-HélèneA.-H. Olivier, ClaudioC. Pacchierotti and JulienJ. Pettré. Crowd Navigation in VR: exploring haptic rendering of collisionsIEEE Transactions on Visualization and Computer Graphics2020, 12
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• 14 articleLudovicL. Burg, ChristopheC. Lino and MarcM. Christie. Real-time Anticipation of Occlusions for Automated Camera Control in Toric SpaceComputer Graphics Forumxx2July 2020, 1 - 11
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• 15 articleMartinM. Caroline, AnthonyA. Sorel, PierreP. Touzard, BenoitB. Bideau, RonanR. Gaborit, HugoH. DeGroot and RichardR. Kulpa. Can the Open Stance Forehand Increase the Risk of Hip Injuries in Tennis Players?Orthopaedic Journal of Sports Medicine812December 2020, 8
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• 16 articleCharlesC. Faure, AnnabelleA. Limballe, BenoitB. Bideau and RichardR. Kulpa. Virtual reality to assess and train team ball sports performance: A scoping reviewJournal of Sports Sciences382January 2020, 192-205
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• 17 articleRebeccaR. Fribourg, FerranF. Argelaguet Sanz, AnatoleA. Lécuyer and LudovicL. Hoyet. Avatar and Sense of Embodiment: Studying the Relative Preference Between Appearance, Control and Point of ViewIEEE Transactions on Visualization and Computer Graphics265May 2020, 2062-2072
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• 18 article RebeccaR. Fribourg, NamiN. Ogawa, LudovicL. Hoyet, FerranF. Argelaguet Sanz, TakujiT. Narumi, MichitakaM. Hirose and AnatoleA. Lécuyer. Virtual Co-Embodiment: Evaluation of the Sense of Agency while Sharing the Control of a Virtual Body among Two Individuals IEEE Transactions on Visualization and Computer Graphics June 2020
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• 19 articleNilsN. Hareng, BrunoB. Watier and FranckF. Multon. Prediction of plausible locomotion using nonlinear kinematic optimizationComputer Methods in Biomechanics and Biomedical Engineering23sup1November 2020, S136-S138
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• 20 article SimonS. Hilt, ThomasT. Meunier, CharlesC. Pontonnier and GeorgesG. Dumont. Biomechanical fidelity of simulated pick-and-place tasks: impact of visual and haptic renderings IEEE Transactions on Haptics (ToH) 2021
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• 21 articleCamilleC. Jeunet, LucaL. Tonin, LouisL. Albert, RicardoR. Chavarriaga, BenoitB. Bideau, FerranF. Argelaguet Sanz, José Del R.J. Millán, AnatoleA. Lécuyer and RichardR. Kulpa. Uncovering EEG Correlates of Covert Attention in Soccer Goalkeepers: Towards Innovative Sport Training ProceduresScientific Reports101February 2020, 1705
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• 22 article HongdaH. Jiang, BinB. Wang, XiX. Wang, MarcM. Christie and BaoquanB. Chen. Example-driven virtual cinematography by learning camera behaviors ACM Transactions on Graphics 39 4 July 2020
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• 23 article SeanS. Lynch, RichardR. Kulpa, Laurentius AntoniusL. Meerhoff, AnthonyA. Sorel, JulienJ. Pettré and Anne-HélèneA.-H. Olivier. Influence of path curvature on collision avoidance behaviour between two walkers Experimental Brain Research 2020
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• 24 articleAntonioA. Mucherino, JérémyJ. Omer, LudovicL. Hoyet, PaoloP. Robuffo Giordano and FranckF. Multon. An application-based characterization of dynamical distance geometry problemsOptimization Letters1422020, 493–507
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• 25 articleAntoineA. Muller, CharlesC. Pontonnier and GeorgesG. Dumont. Motion-based prediction of hands and feet contact efforts during asymmetric handling tasksIEEE Transactions on Biomedical Engineering672February 2020, 344-352
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• 26 articleAntoineA. Muller, CharlesC. Pontonnier, XavierX. Robert-Lachaine, GeorgesG. Dumont and AndréA. Plamondon. Motion-based prediction of external forces and moments and back loading during manual material handling tasksApplied Ergonomics82January 2020, 102935
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• 27 articleCharlesC. Pontonnier and StéphaneS. Salvan. Biomechanical plausibility of the lucanian fresco tomb proto-gladiators paintings of Paestum: a pilot studyComputer Methods in Biomechanics and Biomedical Engineering2020, 1-2
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• 28 articlePierreP. Puchaud, GeorgesG. Dumont, NicolasN. Bideau and CharlesC. Pontonnier. Generic kinematical models of the French soldier from a clustered anthropometric databaseComputer Methods in Biomechanics and Biomedical Engineering23sup12020, S244-S246
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• 29 articleKatjaK. Zibrek, BenjaminB. Niay, Anne-HélèneA.-H. Olivier, LudovicL. Hoyet, JulienJ. Pettré and RachelR. Mcdonnell. The effect of gender and attractiveness of motion on proximity in virtual realityACM Transactions on Applied Perception174November 2020, 1-15
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National journals

• 30 articleSimonS. Hilt, CharlesC. Pontonnier and GeorgesG. Dumont. Biomechanical fidelity assessment of a pick and place task with haptic feedback in virtual realityComputer Methods in Biomechanics and Biomedical Engineering2020, 1-2
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International peer-reviewed conferences

• 31 inproceedingsFlorianF. Berton, LudovicL. Hoyet, Anne-HélèneA.-H. Olivier, JulienJ. Bruneau, OlivierO. Le Meur and JulienJ. Pettré. Eye-Gaze Activity in Crowds: Impact of Virtual Reality and DensityVR 2020 - 27th IEEE Conference on Virtual Reality and 3D User InterfacesAtlanta, United StatesMarch 2020, 1-10
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• 32 inproceedingsHugoH. Brument, MaudM. Marchal, Anne-HélèneA.-H. Olivier and FerranF. Argelaguet Sanz. Influence of Dynamic Field of View Restrictions on Rotation Gain Perception in Virtual EnvironmentsEuroVR 2020 - 17th EuroVR International ConferenceValencia, SpainOctober 2020, 20-40
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• 33 inproceedingsHugoH. Brument, Anne-HélèneA.-H. Olivier, MaudM. Marchal and FerranF. Argelaguet. Does the Control Law Matter? Characterization and Evaluation of Control Laws for Virtual Steering NavigationICAT-EGVE 2020 - International Conference on Artificial Reality and Telexistence & Eurographics Symposium on Virtual EnvironmentsFlorida, United StatesDecember 2020, 1-10
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• 34 inproceedingsDianeD. Dewez, LudovicL. Hoyet, AnatoleA. Lécuyer and FerranF. Argelaguet. Studying the Inter-Relation Between Locomotion Techniques and Embodiment in Virtual RealityIEEE International Symposium on Mixed and Augmented Reality (ISMAR)Arrecife, Brazil2020, 1-10
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• 35 inproceedingsT. Duverné, T. Rougnant, FrançoisF. Le Yondre, F. Berton, J. Bruneau, JulienJ. Pettré, LudovicL. Hoyet and Anne-HélèneA.-H. Olivier. Effect of Social Settings on Proxemics During Social Interactions in Real and Virtual Conditions17th International Conference on Virtual Reality and Augmented Reality, EuroVR 202012499 LNCSLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)Valencia, Spain2020, 3-19
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• 36 inproceedingsVictoriaV. Fernández Abrevaya, AdnaneA. Boukhayma, Philip H. S.P. Torr and EdmondE. Boyer. Cross-modal Deep Face Normals with Deactivable Skip ConnectionsCVPR 2020 - IEEE Conference on Computer Vision and Pattern RecognitionSeattle, United StatesJune 2020, 1-11
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• 37 inproceedingsRebeccaR. Fribourg, EvanE. Blanpied, LudovicL. Hoyet, AnatoleA. Lécuyer and FerranF. Argelaguet Sanz. Influence of Threat Occurrence and Repeatability on the Sense of Embodiment and Threat Response in VRICAT-EGVE 2020 - International Conference on Artificial Reality and Telexistence & Eurographics Symposium on Virtual EnvironmentsFlorida, United StatesDecember 2020, 1-9
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• 38 inproceedingsAlbertoA. Jovane, AmauryA. Louarn and MarcM. Christie. Topology-aware Camera Control for Real-time ApplicationsMIG 2020 - Motion, Interaction and GamesN. Charleston, United StatesOctober 2020, 1-9
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• 39 inproceedings AmauryA. Louarn, QuentinQ. Galvane, FabriceF. Lamarche and MarcM. Christie. An interactive staging-and-shooting solver for virtual cinematography Motion in Games Charleston, France October 2020
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• 40 inproceedingsBenjaminB. Niay, Anne-HélèneA.-H. Olivier, KatjaK. Zibrek, JulienJ. Pettré and LudovicL. Hoyet. Walk Ratio: Perception of an Invariant Parameter of Human Walk on Virtual CharactersSAP 2020 - ACM Symposium on Applied PerceptionVirtual Event, United StatesSeptember 2020, 1-9
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• 41 inproceedingsNicolasN. Olivier, LudovicL. Hoyet, FerranF. Argelaguet, FabienF. Danieau, QuentinQ. Avril, PhilippeP. Guillotel, AnatoleA. Lécuyer and FranckF. Multon. The impact of stylization on face recognitionSAP 2020 - ACM Symposium on Applied PerceptionVirtual, United StatesSeptember 2020, 1-9
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• 42 inproceedingsXiX. Wang, MarcM. Christie and EricE. Marchand. Relative Pose Estimation and Planar Reconstruction via Superpixel-Driven Multiple HomographiesIROS 2020 - IEEE/RSJ International Conference on Intelligent Robots and SystemsLas Vegas, United StatesOctober 2020, 1-8
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• 43 inproceedingsKatjaK. Zibrek, BenjaminB. Niay, Anne-HélèneA.-H. Olivier, LudovicL. Hoyet, JulienJ. Pettré and RachelR. Mcdonnell. Walk this way: Evaluating the effect of perceived gender and attractiveness of motion on proximity in virtual realityVR 2020 - 27th IEEE Conference on Virtual Reality and 3D User InterfacesVirtuel, United States2020, 169-170
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Conferences without proceedings

• 44 inproceedings OlfaO. Haj Mahmoud, CharlesC. Pontonnier, GeorgesG. Dumont, StéphaneS. Poli and FranckF. Multon. Posture Assessment and Subjective Scale Agreement in Picking Tasks with Low Masses AHFE - 11th Applied Human Factors and Ergonomics Conference San Diego, United States July 2020
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• 45 inproceedings PierreP. Puchaud, SimonS. Kirchhofer, GeorgesG. Dumont, NicolasN. Bideau and CharlesC. Pontonnier. Dimension Reduction of Anthropometric Measurements with Support Vector Machine for Regression: Application to a French Military Personnel Database AHFE - 11th Applied Human Factors and Ergonomics Conference San Diego, United States July 2020
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• 46 inproceedings CaroleC. Puil, Anne-HélèneA.-H. Olivier and ArmelA. Crétual. Clinical evaluation of plantar exteroceptive inefficiency: normalisation of Plantar quotient ENPODHE Malaga, Spain 2020
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Doctoral dissertations and habilitation theses

• 47 thesis SimonS. Hilt. Haptics Virtual Reality Biofidelity Ergonomics École normale supérieure de Rennes December 2020
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• 48 thesis PierreP. Puchaud. Generic and specific musculoskeletal modeling for the support of the soldier's physical activity École normale supérieure de Rennes December 2020
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Reports & preprints

• 49 misc AlexandreA. Bruckert, MarcM. Christie and OlivierO. Le Meur. Where to look at the movies : Analyzing visual attention to understand movie editing February 2021
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Other scientific publications

• 50 misc AdèleA. Colas, WouterW. Van Toll, LudovicL. Hoyet, ClaudioC. Pacchierotti, MarcM. Christie, KatjaK. Zibrek, Anne-HélèneA.-H. Olivier and JulienJ. Pettré. Interaction Fields: Sketching Collective Behaviours N. Charleston, United States October 2020
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• 51 misc RebeccaR. Fribourg, FerranF. Argelaguet Sanz, AnatoleA. Lécuyer and LudovicL. Hoyet. Avatar et Sentiment d'Incarnation : Étude de la préférence relative entre l'apparence, le contrôle et le point de vue Saint Pierre d'Oléron, France June 2020
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