关键词: 蛇形臂机器人, 运动规划, 末端轨迹跟随, 模型降噪, 刚柔耦合

Abstract:  Based on dynamics model smoothing formulation of equivalent multi-link system, a tip-trajectory following algorithm was proposed for motion planning of hyper-redundant SARs in narrow and confined spaces. Regarding SAR as a multi-link system of joint points constrained to move on collision-free trajectory curve of tip, and the dynamics equation of rigid-flexible coupling system was derived using virtual work principle. The length conditions of robot arm segments were guaranteed by axial stiffness of connecting rods, and the influences of high-frequency components were filtered out from the model level by employing model denoising method, so that the conventional explicit algorithm might be used to calculate the solution of equation of equivalent multi-link system efficiently. The proposed algorithm may specify the velocity law of tip or base of snake-arms, and realize the motion planning of SAR along tip-trajectory. Due to the strictly limited joint points of SAR moving on feasible trajectory curve, obstacle avoidance motion planning may be achieved in narrow and deep cavity environments. After solving typical numerical examples in planar and spatial cases, the results show that the proposed algorithm has sufficient computational accuracy and efficiency for the motion planning of SARs.

Key words: snake-arm robot(SAR), motion planning, tip-trajectory following, model denoising, rigid-flexible coupling