液压驱动六足机器人步行腿节段长度比例研究

On the Segment Length Ratio of the Walking Leg of a Hydraulically Actuated Hexapod Robot

针对液压驱动六足机器人三节段步行腿,建立了运动学模型,规划了足端运动轨迹,分析了腿长比例对步行速度、关节速度和加速度、足端工作空间及机体灵活度的影响.发现基节比例在0-0.1之间、大腿比例在0.4-0.5之间时,各项指标处于合理范围.根据0.09：0.455：0.455的腿长比例建立了腿部实物模型,搭建了腿部性能测试系统.试验结果表明,关节运动过程中未到达液压缸极限位置且无死点;关节最大速度与加速度满足性能需求;各关节最大速度复现偏差小于0.2°/s,最大加速度复现偏差小于0.7°/s2.验证了腿部节段长度分析结果的合理性与可行性.

For a hydraulically actuated hexapod robot, a kinematic model of the walking leg with three segments is es- tablished. The trajectory of foot is planned, and the influence of leg length ratio on walking speed, joint angular velocity and acceleration, workspace of foot and body flexibility is analyzed. The indexes are reasonable when coxa proportion is between 0-0.1 and thigh proportion is between 0.4-0.5. The physical model of leg is established according to the segment length ratio 0.09 ： 0.455 ： 0.455, and the performance testing system of leg is developed. Experimental results show that there is no extreme position of hydraulic cylinder and dead point in the process of joint movement. The maximum speed and the maximum acceleration of joints can satisfy the performance requirements. Repetition deviation of the maximum speed of joints is less than 0.2°/s, and the repetition deviation of the maximum acceleration is less than 0.7° /s2. The rationality and feasibility of the analysis results of segment length are verified.