Feedback Control of Dynamic Bipedal Robot Locomotion (by Westervelt, E.R. et al.; 2007) [Book Review]

Several years ago the authors of this book crafted a feedback control structure and a set of mild hypotheses that enabled them to make the following assertion: a bipedal robot is guaranteed to converge to a periodic orbit (e.g., user-defined gait) if and only if a pair of scalar inequality constraints is satisfied. Practically speaking, the result produces a stable, time-invariant feedback control law - an effective option for getting bipedal robots to walk and jog with robustness. This book is a well-focused, self-contained, and masterfully written account of this result, which includes its mathematical foundations, validation and practical implications. The book itself is divided into three parts. The first part is preliminary and introduces the basic feedback control problem for bipedal robot locomotion. The second section develops the entire analysis and design framework for bipedal robots with point feet. The third section effortlessly adjusts the theory from section two to accommodate bipedal robots with nontrivial feet and actuated ankles. This book will likely serve as an impetus for future work in hybrid systems research.