关节型工业机器人扭转振动的伺服补偿技术研究

针对工业机器人用RV减速机传动误差所引起的动态失稳现象,在建立由驱动电机-RV减速机-负载所构成的机电耦合系统的基础上,同时考虑负载侧不宜安装传感器的限制条件,依据转矩波动引起转速波动的原理,将由状态观测器间接得到的能够反映转矩波动变化的状态变量——负载加速度变化率作为反馈控制量,对电磁转矩进行实时补偿。经系统的时频域性能分析证明,补偿后的电机转矩命令值抵消了转矩波动的影响,负载侧转速波动得到了很好的抑制,能够极大提高工业机器人在变工况下的动态工作精度。

Servo compensation technology for the torsional vibration of industry robots

The dynamic instability of an industry robot is often influenced by the transmission error of its RV reducer.For analysing its mechanism, an electro-mechanical system comprised of motor, RV reducer and load was established.Considering the difficulty of attaching a sensor at the load side of the industry robot, and according to the principle that torque vibration causes rotating speed vibration, the derivative of acceleration at the load side which was derived by a state observer was taken as a feedback variable to compensate for the torque of the motor.The numerical results in time-domain and frequency-domain show that the compensated torque of motor can offset the torque vibration, and the speed vibration at the load side can be suppressed satisfactorily.The proposed system can improve the dynamic precision of industry robots when the working condition is suddenly changed.