Development of Minimalist Bipedal Walking Robot with Flexible Ankle and Split-mass Balancing Systems

This paper presents a novel design of minimalist bipedal walking robot with flexible ankle and split-mass balancing systems. The proposed approach implements a novel strategy to achieve stable bipedal walk by decoupling the walking motion control from the sideway balancing control. This strategy allows the walking controller to execute the walking task independently while the sideway balancing controller continuously maintains the balance of the robot. The hip-mass carry approach and selected stages of walk implemented in the control strategy can minimize the effect of major hip mass of the robot on the stability of its walk. In addition, the developed smooth joint trajectory planning eliminates the impacts of feet during the landing. In this paper, the new design of mechanism for locomotion systems and balancing systems are introduced. An additional degree of freedom introduced at the ankle joint increases the sensitivity of the system and response time to the sideway disturbances. The effectiveness of the proposed strategy is experimentally tested on a bipedal robot prototype. The experimental results provide evidence that the proposed strategy is feasible and advantageous.