Compliant joint modification and real-time dynamic walking implementation on bipedal robot cCub

Abstract

Conventionally, humanoid robots consist of non-backdrivable stiff joint structures with high gain controllers, aiming at high precision. Although this feature enabled researchers to represent outstanding engineering prototypes, the resulting large mechanical impedance output makes these robots inherently unsafe when interacting with humans. Moreover, the same issue also limits their abilities to safely interact with the environment and reduces their energy efficiency. In order to cope with these problems, we developed a compliant robot called cCub, as a part of the European project AMARSi (Adaptive Modular Architectures for Rich Motor Skills). Having completed the design and realization of the lower body of the cCub robot, we developed an integrated framework, including the compliant experimental platform, a simulation environment and a walking pattern generator. Furthermore, we also conducted real-time dynamic walking experiments on cCub demonstrating that dynamically equilibrated walking cycles can be executed in this new highly passive compliant humanoid platform. These preliminary results validate the feasibility of the walking generator and the motion capability of the compliant robot.