Bio-Inspired Gait Trajectory Design for Lizard-Inspired Wall Climbing Robot

Abstract Wall-climbing robots can have potential to be used in a range of areas like surveillance, reconnaissance, cleaning of high-rise building facade, and repairing. This paper presents a few improvements to the gait trajectory of a quadruped, lizard-inspired wall-climbing robot that employs a trot-like gait. The proposed enhancements build upon the earlier work of our research group, which involved the design and fabrication of a wall-climbing lizard-inspired robot that utilized pressure-sensitive adhesion [1]. The robot was equipped with a mechanical switching mechanism for transitioning between adhesion and peeling to effect climbing. However, the gait trajectory employed was not smooth resulting in occasional detachments while climbing. To improve the climbing performance, this paper paper proposes a segmentation of the foot’s path during each step into three separate regimes: peel, stride, and squat. By defining the foot’s path with respect to time increments, we aim to reduce the overall gait time, improve bio-mimicry, and enhance surefootedness. Additionally, we introduce a uniform acceleration and deceleration plan to time the movements of the feet, thereby smoothing the dynamics of the gait. Moreover, we introduce a real-time method to smoothly transition the steering angle of the robot. These proposed improvements are expected to broaden the operational capabilities of the lizard-inspired robot and improve climbing performance.