Bioinspired Phase-Shift Turning Action for a Biomimetic Robot

The capability of performing animal-like turning action is very important for a biomimetic robot to be used in realistic world. Although the existed biomimetic robots can imitate turning actions of their counterparts, it is still lacking an effective approach to generate bioinspired turning action of small quadruped animals. To solve this problem, we proposed an effective phase-shift-based motion planning method after systematically analyzing and mathematically modeling the turning action of laboratory rats. Moreover, we introduced an N-step turning strategy to allow the biomimetic robot effectively perform animallike turning action regardless of joint limits. We characterized the action similarity between rats and a rat-inspired robot in terms of joint trajectory and their envelope. The robot is able to closely follow the turning action of rats since the difference of turning angle is less than 7.95. Additionally, the width distribution of trajectory envelope between the robot and rat is quite similar. The proposed turning model can be easily extended to biomimetic robots inspired by other small quadruped mammals, which share similar turning patterns to rats.