Walking and Running with Passive Compliance: Lessons from Engineering: A Live Demonstration of the ATRIAS Biped

Biological bipeds have long been thought to take advantage of compliance and passive dynamics to walk and run, but realizing robotic locomotion in this fashion has been difficult in practice. Assume The Robot Is A Sphere (ATRIAS) is a bipedal robot designed to take advantage of the inherent stabilizing effects that emerge as a result of tuned mechanical compliance (Table 1). In this article, we describe the mechanics of the biped and how our controller exploits the interplay between passive dynamics and actuation to achieve robust locomotion. We outline our development process for the incremental design and testing of our controllers through rapid iteration.