Development and Analysis of a Biped Robot with Prismatic Compliance

Previous studies suggest that bipedal robots that have prismatic compliance in the legs can achieve efficient walking. However, how this efficiency can be achieved still remains an open research problem. In this study, we developed a 2-degree-of-freedom planar bipedal robot comprising Neidhart springs and five-bar parallel mechanisms. The five-bar parallel mechanism allows the robot to achieve prismatic compliance. In addition, a lightweight torque limiter function is achieved by Neidhart springs with an original design. We implemented a simple controller and conducted walking experiments. Experimental results showed that the robot walked effectively using the regenerative energy stored in the prismatic springs.