A compliant, force-controlled active tail for miniature robots

Abstract

Climbing up the slopes and scaling the obstacles are challenging tasks for miniature robots. By taking inspiration from nature, this paper investigates the use of a tail, like a lizard to aid the climbing capabilities of our miniature robot. We present the design of an active soft tail controlled by the force feedback from a 3D-printed, custom, soft force sensor. This paper also investigates the benefit of using an active tail controlled by force to climb slopes and obstacles. Increasing the slope that the miniature robot attempts to scale increases the need for the force applied by the tail to avoid the pitch-back movement of the robot. We can observe a positive correlation between the force applied by the tail and the slope of the surface. The experiments were conducted until the maximum degree of incline of slope that the robot could climb without any adhesive feet, i.e., 20 degrees. Additionally, this paper proves that the tail also improves the tail obstacle scaling capability of the robot. The maximum heights of the obstacle that the robot scales with and without the tail are 19 mm and 9 mm respectively.