Control Scheme and Uncertainty Considerations for Dynamic Balancing of Passive-Ankled Bipeds and Full Humanoids

Abstract- We will present a methodology for dynamically balancing passive-ankled bipeds and full humanoids. As dynamic locomotion without ankle-actuation is more difficult than with actuated feet, our control scheme adopts an efficient whole-body controller that combines inverse kinematics, contact- consistent feed-forward torques, and low-level motor position controllers. To understand real-world sensing and controller requirements, we will discuss an uncertainty analysis on the linear-inverted-pendulum (LIP)-based footstep planner. This will enables us to identify necessary hardware and control refinements to demonstrate that our type of controller can achieve long-term unsupported dynamic balancing on series-elastic bipeds like Mercury.

400xX_scaleLuis Sentis is an Associate Professor in Aerospace Engineering at the University of Texas at Austin and co-founder of Apptronik Systems. He received Ph.D. and M.S. degrees in Electrical Engineering from Stanford University and was a La Caixa Foundation Fellow. He leads the Human Centered Robotics Laboratory, an experimental facility focusing on control and embodiment of agile humanoid robots. He writes extensively and teaches courses in areas related to realtime control of human-centered robots, design of high performance humanoid robots, and safety protocols in robotics. He was awarded the NASA Elite Team Award for his contributions to NASA’s Johnson Space Center Software Robotics and Simulation Division. He has been a speaker in popular events such as SXSW and Hot Science – Cool Talks. Luis is co-chair for the ASTM International Standards Committee of Exoskeletons and Exosuits and serves as an advisor for the UT System Federal Office National Security Advisory Group