基于导纳的机械臂实时柔顺轨迹规划

Real-Time Compliant Trajectory Planning of Manipulator Based on Admittance Control

针对传统机械臂的离线式笛卡尔空间轨迹规划无法解决与环境发生接触的情况,提出了一种基于导纳的机械臂实时柔顺轨迹规划方法。将机械臂笛卡尔空间轨迹规划分为了位置规划与姿态轨迹,并通过时间标度参数s(t)将二者归一化,其中以最为常见的直线运动和圆弧运动为例进行了轨迹规划说明;构建导纳控制器,并将末端六维力传感器获取到的信息代入控制器中,计算出末端位姿的调整量;在轨迹规划的基础上引入导纳控制,解决了轨迹规划无法实时感知外界环境作用力的问题;最后,搭建了机械臂实物验证实验,进行了直线运动和和圆弧运动实验。实验表明,基于导纳的实时柔顺轨迹规划方法既可以实现机械臂轨迹高精度运动,也可以主动顺从外界环境接触力,提高了系统的稳定性和安全性。

In view of the fact that the offline Cartesian space trajectory planning of the traditional manipulator cannot solve the problem of the contact with the environment,a real-time compliant trajectory planning method based on admittance control was proposed;The trajectory planning of manipulator in Cartesian space was divided into position planning and attitude planning,and the two were normalized by the time scale parameter s(t).The trajectory planning method was illustrated by taking the most common linear motion and circular motion as examples;An admittance controller was constructed,and the information obtained by the six-dimension force sensor was substituted into the controller to calculate the adjustment of the end pose;On the basis of trajectory planning,admittance control is introduced to solve the problem that trajectory planning cannot perceive the forces of the external environment in real time;Finally,the verification experiments of the manipulator were built,and the experiments of linear motion and circular motion were carried out;Experimental results show that the proposed method can not only achieve the high precision of the manipulator trajectory,but also actively comply the contact force of the external environment,which improves the stability and safety of the control system.