Development of Four-legged Robot with Driven Joints

Abstract

We are developing a four-legged robot with ten driving joins: two for the forelegs, and three for the hind legs. In this paper, we present a new leg mechanism for our four-legged robot with driven joints, its control, and experimental results on the energy consumption. Previously, each joint is driven by a D.C. motor, which increases the robot’s mass and make its walking without supports difficult. Thus, we reduced the number of the active joints by introducing the driven joint to the ankle joints in the hind legs. Due to the leg mechanism change, the trajectory of the toe does not follow the indicated trajectory. We solve this problem by adjusting the PID parameters. As a result, the error of the toe trajectory become small, although it does not be completely eliminated. In addition, we succeeded in reducing the energy consumption of the entire leg.