Abstract

Human dexterity and agility vastly exceed that of contemporary robots. Yet humans have vastly slower ‘hardware’ (e.g. muscles) and ‘wetware’ (e.g. neurons). How can this paradox be resolved? Slow actuators and long communication delays require predictive control based on some form of internal model—but what form? I will argue that a plausible answer is based on dynamic primitives; they enable highly dynamic behavior with minimal high-level supervision and intervention. Controlling physical interaction requires mechanical impedance to be among the classes of dynamic primitives. I will review how pre-computing appropriate mechanical impedance may be cast as an optimization problem, provided the objective function includes both force and motion at an interaction port. To combine both motion and interaction primitives, I propose a nonlinear generalization of the classical equivalent circuit. It reconciles contrasting constraints of information-processing (computation) and energy-processing (physical dynamics). I suggest that nonlinear equivalent networks provide a general basis for the internal models required for high-performance interactive control.

Additional Information

Host: Matt Mason

Appointments: Jean Harpley (js3g@andrew.cmu.edu)Speaker Biography

Neville Hogan is Professor of Mechanical Engineering, Professor of Brain and Cognitive Sciences and Director of the Newman Laboratory for Biomechanics and Human Rehabilitation at the Massachusetts Institute of Technology. He is a co-founder of Interactive Motion Technologies, Inc., and a board member of Advanced Mechanical Technologies, Inc. Born in Dublin, Ireland, he earned a Dip. Eng. (with distinction) from Dublin College of Technology and M.S., M.E. and Ph.D. degrees from MIT. Following industrial experience in engineering design, he joined MIT’s School of Engineering faculty in 1979 and has served as Head and Associate Head of the Mechanical Engineering department’s System Dynamics and Control division. Awards include an Honorary Doctorate from the Delft University of Technology; the Silver Medal of the Royal Academy of Medicine in Ireland; and an Honorary Doctorate from the Dublin Institute of Technology. Professor Hogan’s research is broad and multi-disciplinary, extending from biology to engineering—it has made significant contributions to motor neuroscience, rehabilitation engineering and robotics—but its focus converges on an emerging class of machines designed to cooperate physically with humans. Recent work pioneered the creation of robots sufficiently gentle to provide physiotherapy to frail and elderly patients recovering from neurological injury such as stroke, a novel therapy that has already proven its clinical significance.