Over the last two decades, the foundations for physical human–robot interaction (pHRI) have evolved from successful developments in mechatronics, control, and planning, leading toward safer lightweight robot designs and interaction control schemes that advance beyond the current capacities of existing high-payload and highprecision position-controlled industrial robots. Based on their ability to sense physical interaction, render compliant behavior along the robot structure, plan motions that respect human preferences, and generate interaction plans for collaboration and coaction with humans, these novel robots have opened up novel and unforeseen application domains, and have advanced the field of human safety in robotics.
This chapter gives an overview on the state of the art in pHRI as of the date of publication. First, the advances in human safety are outlined, addressing topics in human injury analysis in robotics and safety standards for pHRI. Then, the foundations of human-friendly robot design, including the development of lightweight and intrinsically flexible force/torque-controlled machines together with the required perception abilities for interaction are introduced. Subsequently, motionplanning techniques for human environments, including the domains of biomechanically safe, risk-metric-based, human-aware planning are covered. Finally, the rather recent problem of interaction planning is summarized, including the issues of collaborative action planning, the definition of the interaction planning problem, and an introduction to robot reflexes and reactive control architecture for pHRI.
A cobot in automobile assembly
Author Prasad Akella, Nidamaluri Nagesh, Witaya Wannasuphoprasit, J. Edward Colgate, Michael Peshkin
Video ID : 821
Collaborative robots - cobots - are a new class of robotic devices for direct physical interaction with a human operator in a shared workspace. Cobots implement software-defined "virtual surfaces" which can guide human and payload motion. A joint project of General Motors and Northwestern University has brought an alpha prototype cobot into an industrial environment. This cobot guides the removal of an automobile door from a newly painted body prior to assembly. Because of tight tolerances and curved parts, the task requires a specific escape trajectory to prevent collision of the door with the body. The cobot's virtual surfaces provide physical guidance during the critical "escape" phase, while sharing control with the human operator during other task phases. (Video Proceedings of the Int. Conf. on Robotics and Automation, 1999)