An experimental study on the locomotion performance of elliptic-curve leg in muddy terrain

Adapting to the complex environment is significant for field robots. The field robots equipped with elliptic-curve legs which combine the advantages of legs and wheels, have achieved a good locomotion performance in terrain, while the leg-terrain dynamics has not been explored intensely, especially elliptic-curve legs passing through the soft substrate, such as muddy terrain. In this paper, an experimental platform for locomotion performances of elliptic-curve legs in muddy terrain is designed. With the platform, locomotion parameters of the elliptic-curve legs including forward speed, propulsion force, and torque output can be recorded and analyzed. The influences from the shapes of legs and the water content of muddy substrates are studied. The results indicate that the propulsive efficiency is higher when reducing the rotating speed of elliptic-curve legs in a higher water content substrate, and there are an optimal rotating speed for certain shapes of the legs to achieve a higher forward speed, which is meaningful for the mechanical design and the control of the field robots.