机器人带未知负载条件下的碰撞检测算法

未知负载会增大机器人模型误差,对碰撞检测产生严重干扰,甚至导致算法失效.为此,本文提出了一种适用于机器人带负载工作情况的碰撞检测算法.首先,基于机器人广义动量设计具有带通滤波特性的新型力矩观测器,通过对机器人动力学频域特性进行分析,得到机器人动力学模型与关节运行速度对应的最大频率阈值,确定带通力矩观测器的参数.然后,利用带通力矩观测器对关节力矩信号进行滤波,提高碰撞检测算法对机器人模型误差的容忍度.最后,通过人与机器人交互实验进一步验证了该碰撞检测算法的有效性.实验结果表明,该算法与已有的算法相比具有更好的鲁棒性,可满足机器人带未知负载0～2 kg的工作需求.

Collision Detection Algorithm for Robots with Unknown Payload

The unknown payload will increase the error of the robot model, which will cause serious interference to the collision detection and even lead to algorithm failure. Therefore, a collision detection algorithm for robots working with payloads is proposed in this paper. Firstly, a novel torque observer with band-pass filtering characteristics is designed based on the generalized momentum of the robot. Through the analysis of the frequency domain characteristics of the robot dynamics, the maximum frequency threshold of the robot dynamics model corresponding to the joint speed is obtained, and the parameters of the band-pass torque observer are determined. Then, the band-pass torque observer is used to filter the joint torque signal to improve the tolerance of the collision detection algorithm to the robot model error. Finally, the effectiveness of the proposed collision detection algorithm is further validated by human-robot interaction experiments. The experimental results show that the proposed algorithm is more robust than existing algorithms, and can meet the needs of the robot with 0～2 kg unknown payload.