Search

Robot-mediated physical interaction between humans, or physical Human-Robot-Human Interaction (pHRHI for short) can transcend the physical constraints associated with direct human-human interaction such as constant interaction medium and the need for proximity. Control for pHRHI is related to bilateral teleoperation, but pHRHI must necessarily focus on human safety features on both sides of the interaction in a general setting. This paper presents a safety-aware framework for a robot mediated bilateral physical interaction between two humans in general setting while handling safety constraints with different priorities on two sides. The proposed framework also allows a user to haptically feel any number of constraints that are active on the other side, enabling a safe and intuitive interaction. Additionally, this approach is not dependent on the robot model and allows generalization across robots. We have formulated the safety-aware pHRHI problem as a hierarchical optimization framework with higher-priority safety tasks and lower-priority bilateral interaction and constraint communication tasks. We validated this framework by assessing the bilateral interaction, hierarchical constraint handling, and constraint communication performances on a dual human-robot setup. We also compared the performance with current approaches based on constrained optimization without any hierarchy or constraint communication feature. Results show that the proposed framework can handle prioritized physical/safety constraints, enabling bilateral interaction and providing a physical feeling of the other robot’s constraints.

The majority of Americans will meet the diagnostic criteria of a mental health condition during their lifetime and most will go without treatment oftentimes due to perceived stigma. This study evaluated the impact of the film, “Lift the Mask: Portraits of Life with Mental Illness”, on stigma reduction related to mental health conditions. The film ran from 2018 to 2020 and was across the United States. A total of 254 people completed a pre and post survey and were eligible for this analysis. Paired t-tests using a matched sample of participant pre and post surveys were used to assess change in attitudes toward mental health conditions before and after the film screening and results were stratified by mental health professionals and non-mental health professionals. After viewing the film, stigma related to mental health conditions was significantly reduced among mental health professionals and those outside the profession. Films focused on humanizing mental health conditions can reduce stigma and should be incorporated into interventions. [Figure: see text]

We investigate in-hand regrasping by pushing an object against an external constraint and allowing sliding at the fingertips. Each fingertip is modeled as attached to a multidimensional spring mounted to a position-controlled anchor. Spring compliance maps contact forces to spring compressions, ensuring the fingers remain in contact, and sliding “compliance” governs the relationship between sliding motions and tangential contact forces. A spring-sliding compliant regrasp is achieved by controlling the finger anchor motions. We derive the fingertip sliding mechanics for multifingered sliding regrasps and analyze robust regrasping conditions in the presence of finger contact wrench uncertainties. The results are verified in simulation and experiment with a two-fingered sliding regrasp designed to maximize robustness of the operation.

This paper examines the problem of planning and stabilizing the trajectory of one smooth body rolling on the surface of another. The two control inputs are the angular velocity of the moving body about two orthogonal axes in the contact tangent plane; spinning about the contact normal is not allowed. To achieve robustness and computational efficiency, our approach to trajectory planning is based on solving a series of optimization problems of increasing complexity. To stabilize the trajectory in the face of perturbations, we use a linear quadratic regulator. We apply the approach to examples of a sphere rolling on a sphere and an ellipsoid rolling on an ellipsoid. Finally, we explore the robustness and performance of the motion planner. Although the planner is based on non-convex optimization, in practice the planner finds solutions to nearly all randomly-generated tasks, and the solution trajectories are smoother and shorter than those found in previous work in the literature.

In this paper, we present a feedback controller that enables contact juggling manipulation of a disk with a disk-shaped manipulator, called the mobile disk-on-disk. The system consists of two disks in which the upper disk (object) is free to roll on the lower disk (hand) under the influence of gravity. The hand moves with a full three degrees of freedom in a vertical plane. The proposed controller drives the object to follow a desired trajectory through rolling interaction with the hand. Based on the mathematical model of the system, dynamic feedback linearization is used in the design of the controller. The performance of the controller is demonstrated through simulations considering disturbances and uncertainties.