论文部分内容阅读
针对空间机械臂关节存在的非线性摩擦问题,提出了一种非线性摩擦建模及补偿方法。首先,根据建立的机械臂关节动力学方程推导出非线性摩擦与电机电流、角加速度的关系;然后,通过测得的机械臂关节角度信号,设计了Kalman-牛顿预测器来估计负载端的角加速度,并利用估计的角加速度和采样电流值计算出摩擦力矩,建立机械臂关节的指数摩擦模型;最后,基于该模型设计了前馈补偿控制器,用于对机械臂关节的非线性摩擦进行补偿。通过机械臂关节驱动实验验证了此方法的可行性。
Aiming at the problem of nonlinear friction in space manipulator joints, a nonlinear friction modeling and compensation method is proposed. Firstly, the relationship between nonlinear friction and motor current and angular acceleration is deduced based on the established joint dynamics equations of the manipulator. Then, a Kalman-Newton predictor is designed to estimate the angular acceleration of the load at the measured manipulator joint angle signal , And calculate the friction torque by using the estimated angular acceleration and sampling current value to establish the exponential friction model of the manipulator joint. Finally, a feedforward compensation controller is designed based on the model to compensate the nonlinear friction of the manipulator joint . The feasibility of this method is verified by manipulator joint drive experiment.