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Optical waveguide deformation sensors are created for less than 15 US Dollars each and evaluated for their usefulness in detecting the severity of wrinkles in a thin-walled soft robot. This severity is quantified by the bend angle produced in the robot. The sensors are integrated into the skin of the robot and tests are performed to determine their usefulness. The sensors prove to be able to accurately track the bend angle of the robotic arm as a wrinkle is induced in a sudden load drop test, a sudden pressure loss test, an incremented load test, and an incremented pressure test. The drop test, specifically, tracked bend angle through many rapid undulations. 

In the 21st century workplace (especially in COVID times), much human social interaction occurs during virtual meetings. Unlike traditional screen-based remote meetings, VR meetings promise a more richly embodied form of communication. This paper maps the experiential terrain of seven commercial VR meeting applications, with a particular focus on the range of shared social experiences and collaborative abilities these applications may enable or constrain. We examine a range of applications including Spatial, Glue VR, MeetinVR, Mozilla Hubs, VRChat, AltspaceVR, and Rec Room. We analyze and map avatar system strategies, meeting environments and in-world cues, meeting invitation model, and different models of participation. In addition, we argue that commercial applications for meeting in VR that cater to workplace contexts might benefit from borrowing some of the strategies used in more leisure-focused environments for supporting social interaction. 

This paper describes a series of endurance and material property tests conducted on a pneumatic, fabric-reinforced inflatable soft actuator made of Dragon Skin 30 silicone, which exhibited performance variations during operation. It is important to understand the level of variation over time and how it affects the motions of the soft actuators. The tests were designed to investigate the repeatability and durability of the actuator by measuring changes in its trajectories after long working periods, determining its failure pressure, and examining its elasticity through tensile tests. The experiments were performed on multiple soft actuators, and the results show pertinent information about the variation in their motion and how it relates to the material behavior of the silicone. This information enhances our understanding of the real-world behavior of silicone soft actuators and enables us to better control their performance in our applications.

 

This paper proposes a new method to measure the pose and localize the contacts with the surrounding environment for an inflatable soft robot by using optical sensors (photocells), inertial measurement units (IMUs), and a pressure sensor. These affordable sensors reside entirely aboard the robot and will be effective in environments where external sensors, such as motion capture, are not feasible to use. The entire bore of the robot is used as a waveguide to transfer the light. When the robot is working, the photocell signals vary with the current shape of the robot and the IMUs measure the orientation of its tip. Analytical functions are developed to relate the photocell signals and the robot pose. Since the soft robot is deformable, the occurrence of contact at any location on its body will modify the sensor signals. This simple measurement approach generates enough information to allow contact events to be detected and classified with high precision using a machine learning algorithm. 

This paper presents an observer architecture that can estimate a set of configuration space variables, their rates of change and contact forces of a fabric-reinforced inflatable soft robot. We discretized the continuum robot into a sequence of discs connected by inextensible threads; this allows great flexibility when describing the robot’s behavior. At first, the system dynamics is described by a linear parameter-varying (LPV) model that includes a set of subsystems, each of which corresponds to a particular range of chamber pressure. A real-world challenge we confront is that the physical robot prototype exhibits a hysteresis loop whose directions depend on whether the chamber is inflating or deflating. In this paper we transform the hysteresis model to a semilinear model to avoid backward-in-time definitions, making it suitable for observer and controller design. The final model describing the soft robot, including the discretized continuum and hysteresis behavior, is called the semilinear parameter-varying (SPV) model. The semilinear parameter-varying observer architecture includes a set of sub-observers corresponding to the subsystems for each chamber pressure range in the SPV model. The proposed observer is evaluated through simulations and experiments. Simulation results show that the observer can estimate the configuration space variables and their rate of change with no steady-state error. In addition, experimental results display fast convergence of generalized contact force estimates and good tracking of the robot’s configuration relative to ground-truth motion capture data. 

COVID underscores the potential of VR meeting tools to compensate for lack of embodied communication in applications like Zoom. But both research and commercial VR meeting environments typically seek to approximate physical meetings, instead of exploring new capacities of communication and coordination. We argue the most transformative features of VR (and XR more broadly) may look and feel very different from familiar social rituals of physical meetings. Embracing “weird” forms of sociality and embodiment, we incorporate inspiration from a range of sources including: (1) emerging rituals in commercial social VR, (2) existing research on social augmentation systems for meetings, (3) novel examples of embodied VR communication, and (4) a fictionalized vignette envisioning a future with aspects of “Weird Social XR” folded into everyday life. We call upon the research community to approach these speculative forms of alien sociality as opportunities to explore new kinds of social superpowers.