基于 GMS 摩擦力补偿和干扰观测器的高精度速度控制

为了降低机械轴系摩擦力扰动对于伺服控制器在低速运动控制精度的影响，进一步提高传统伺服控制器对于稳定平 台的控制能力，提出了一种基于广义 Maxwell 滑动(generalized Maxwell-slip,GMS) 摩擦力模型前馈和干扰观测器的高精度 摩擦力补偿方案。首先在传统控制基础上引入GMS 摩擦模型前馈补偿对摩擦扰动进行初步的补偿；然后，通过加入干扰观 测器，对残余扰动及其他扰动进行第2次的抑制。利用实物平台对控制方法的低速运动性能进行了测试，对比设计的控制算 法和传统 PI 控制器的控制结果，验证提出的控制策略抑制摩擦扰动的效果。结果表明，基于 GMS 摩擦力前馈和干扰观测器 的控制方案有效的补偿了摩擦非线性、模型不确定性等因素对于控制系统的影响。新方法可将稳定平台低速运动时的控制 误差降低到0.015°/s, 在实际工程中具有较高的应用价值。

High precision speed control based on GMS friction compensation and disturbance observer

In order to reduce the impact of mechanical shaft friction disturbance on the control accuracy of servo controllers in low-speed motion,a high-precision friction compensation scheme based on the generalized Maxwell-slip (GMS)friction model feedforward and disturbance observer is proposed.Firstly,based on traditional control,the GMS friction model feedforward compensation is introduced to preliminarily compensate for the impact of friction disturbance; Then,the residual disturbances that still exist after friction compensation are further suppressed through the design of interference observers.In order to verify the effectiveness of the proposed control strategy in suppressing friction disturbances in mechanical shaft systems,the low-speed motion dynamic performance of the control method was tested using a physical platform,and the control error was compared between the traditional PI controller and the friction compensation scheme based on disturbance observer before and after.The comparison results show that the control scheme based on GMS friction feedforward and disturbance observer effectively compensates for the influence of privacy such as mechanical friction nonlinearity and model uncertainty on the control system.The new method can reduce the control error of the stable platform during low-speed motion to 0.015°/s,and has high application value in practical engineering.