基于自适应闭环反馈的高空车臂架避障控制研究

Research on Obstacle Avoidance Control of Booms of Aerial Work Platforms Based on Adaptive Closed-loop Feedback

针对改进梯度投影法在混合式高空作业车应用中出现的速度、轨迹不连续以及避障过程中末端速度突变等问题,提出了一种基于自适应闭环反馈的高空车臂架避障控制算法。对改进梯度投影法进行优化,实现了存在伸缩臂的高空车臂架与末端的速度、轨迹连续的运动控制。采用伪距离描述臂架与障碍物的接近程度,对传统避障速度算法进行优化,并提出一种自适应闭环反馈方法,将反馈权重与伪距离相关联,使反馈权重自适应变化。所提算法在保证末端轨迹精度的同时大大改善了臂架关节在避障过程中的速度突变。仿真及半物理实验结果表明,相较于传统方法,所提方法速度变幅大大减小且轨迹更加平滑,实现了多障碍物避障与同一障碍物多次避障。

In order to solve the problems of discontinuity of velocity and trajectory in the applications of the improved gradient projection method in hybrid aerial work platforms and the problems of abrupt change in velocity of ends during obstacle avoidance,an obstacle avoidance motion control algorithm was proposed based on adaptive closed-loop feedback.The improved gradient projection method was optimized to realize the continuous motion control of the speed and trajectory of the booms and the ends of aerial work platforms with telescopic arms.The pseudo distance was used to describe the proximity between the boom and the obstacle,and the traditional obstacle avoidance speed algorithm was optimized.An adaptive closed-loop feedback method was proposed,which correlated the feedback weight with the pseudo-distance,and made the feedback weight change adaptively.The algorithm guaranteed the precision of the end trajectory,and greatly improved the sudden changes in the boom joint velocity in the course of obstacle avoidance.Simulation and semi-physical experimental results verify that the speed amplitude of the proposed method is greatly reduced and the trajectory is smoother than that of the traditional method,and multi-obstacle avoidance and multiple obstacle avoidance may be realized.