Gait Design and Analysis of Quadruped Crawling Robot Climbing Over the Raised Terrain of Slope

Abstract

Background: Quadruped crawling robots face challenges when working in the raised terrain of a slope. The robot is affected by gravity and gait under this terrain. The ground reaction force on its hind legs is relatively large. This has strict requirements for the structure and gait planning of the quadruped crawling robot. Objective: Aimed at the problem of a large ground reaction force on the rear legs of the quadruped crawling robot when crawling on the raised terrain of a slope, a slope-triangular gait walking strategy for quadruped robots based on a layered CGP gait generation method is proposed. Methods: Three-dimensional model of the quadruped crawling robot is created in SOLIDWORKS. The kinematic model is established, and the foot position vector is obtained. Considering the characteristics of the raised terrain of a slope, slope tripod gait and hierarchical CPG slope tripod gait generator are proposed. Comparative simulation of sloped tripod gait and flat tripod gait, the slope tripod gait with and without the gait generator is carried out by Adams programming. Results: When the quadruped crawling robot adopts slope tripod gait and flat tripod gait respectively, the centroid displacement curve, foot speed curve and foot contact force curve are compared. When the quadruped crawling robot adopts the slope tripod gait and does not adopt the slope tripod gait, the body posture curves of the two are compared. The result proves that the tripod gait walking strategy is feasible. Conclusion: The slope tripod gait walking strategy can improve the impact resistance of the quadruped crawling robot on sloped high ground. The gait design and motion analysis process of the robot can provide a reference for other quadruped crawling robot devices.