Analysis of using an active artificial spine in a quadruped robot

Abstract

With increasing mechanization of our daily lives, the expectations and demands in robotic systems increase in the general public and in scientists alike. Especially disaster scenarios shows that the robotic systems not only have to face a variety of different tasks during operation but also have to deal with different demands regarding the robot's mobility characteristics. To be able to cope with future requirements, it seems necessary to develop kinematically complex systems that feature several operating modes. Often disregarded in robotics, yet extensively used in nature, are the degrees of freedom introduced by the spine. This paper presents the latest work on the hominid robot Charlie, whose morphology is oriented on chimpanzees and which has the possibility due to its electromechanical structure and the degrees of freedom to walk with different gaits in different postures. Besides its degrees of freedom in its limbs, the robot features an active artificial spine, equipped with sensors in the structure to allow a dual use; both as a structural part as well as a 6-DoF force/torque sensor. This paper analyses the benefits of an active spine experimentally. The results show, that the exploration of the range of motion is improved and that less requirements on joint velocities are lowered.