The aim of M-Runners is to thoroughly advance the understanding of fundamental dynamic principles of legged locomotion to the point that those principles can be used to design robots which display similar motion characteristics, versatility, and efficiency as their biological paragons. The central hypothesis of the project is that biological locomotion is fundamentally determined by the mechanical resonance properties of the body and that a breakthrough in robot locomotion is essentially linked to understanding and exploiting these phenomena. If body design is such that walking and running correspond to intrinsic periodic motions of the body, then the control is simple and efficiency and robustness are natural consequences. However, large amplitude nonlinear oscillations of such complex systems were theoretically not well understood before the euROBIN project. Mathematical methods to describe, analyze, design and control elastic resonant robots were lacking to a large extent. The project was thus dedicated to develop a new theory of nonlinear oscillations, applicable to elastic multibody systems, be they biologic or robotic.
M-Runners performed interdisciplinary research at the border between robotics, nonlinear dynamical systems, biomechanics, and machine learning. We take inspiration from biology regarding the basic motion sequences and the muscle arrangements (couplings, redundancies, compliance distributions). Conversely, we expect our theory to generate new hypotheses for a deeper understanding of locomotion biomechanics and its control by the nervous system.
The project succeeded to develop a new theory of nonlinear oscillations, applicable to elastic multibody systems, in particular to quadruped robots with muscle-like, elastic actuation. Several such robots with increasing complexity and versatility were developed in a rapid prototyping approach, as validation platforms for the developed methodology.
We could demonstrate that most of the gait patterns known from biological quadrupeds, such as walking, trotting, or bounding can be efficiently realized on the robot based on the new nonlinear resonance theory and the distinct classes of intrinsic body oscillations discovered with it. For the first time various gaits based on elastic resonant locomotion have been realized on full quadruped robots. Moreover, we have demonstrated that the intrinsic, natural motions of elastic robots can also be easily discovered directly on the hardware by machine learning algorithms.
The quadruped robots were used in space experiments, in which, for the first time, astronauts commanded such robots from the international Space Station ISS in planetary exploration scenarios.
Applications of the technology reach, however, from health-care over personal-assistance to disaster management.
