基于力传感器重力补偿的机器人柔顺控制研究

Robotic Compliant Control Based on Force Sensor Gravity Compensation

基于力觉控制的机器人运动系统能够通过感知外界环境的接触力,实现机器人作业过程中对力和位置的双重控制。为了提高机器人对接触力的感知精度,实现准确的柔顺控制,提出一种基于力传感器重力补偿的机器人柔顺控制方法。首先,通过调整机器人末端姿态,采集机器人不同位姿下力传感器数据,计算机器人底座安装倾角、力传感器零点数据、末端工具重力及重心坐标等参数;然后,利用机器人姿态变换矩阵,实现对力传感器的重力补偿,为机器人柔顺控制提供准确的受力感知;最后,采用导纳控制,实现机器人对物体的抓取搬运。进行了力传感器重力补偿实验及机器人柔顺放置实验,结果表明,该方法能够提高机器人对外界环境感知的精准度,实现精准的机器人柔顺控制。

In order to meet the sensing demand of the contact force between the end load of industrial robot and external environment,a force sensor was installed between the end of robot and load.Force sensor can provide force sensing function in the process of industrial robot operation,which was the basis of robot compliance control.The robot motion system based on force perception control can realize dual control of force and position in the process of robot operation by perceiving the contact force of external environment.In order to improve the robot's perception accuracy of contact force and achieve accurate compliance control,a robotic compliance control method was proposed based on force sensor gravity compensation.The force sensor data of the robot in different postures was firstly collected by adjusting the posture of the robot end,and the installation tilt angle of the robot base,the bias of sensor and the center of gravity coordinates of the end tool were calculated.Then,the robot attitude transformation matrix was used to realize the gravity compensation of the sensor and provide accurate force perception for robot compliance control.Finally,the admittance control method was adopted to realize the robot's grasping and handling of objects.The force sensor gravity compensation experiment and the robot flexible placement experiment were carried out.The experimental data analysis and experimental results showed that the proposed method can improve the accuracy of robot's perception of the external environment and achieve accurate robot flexible control.