LuGre模型可以较为全面地描述动态摩擦现象,但引入了不可观测的鬃毛变形,给LuGre摩擦参数的高效准确辨识带来技术挑战。传统的LuGre摩擦参数辨识法需要运动系统采用力矩控制,且辨识工作量较大。传统方法不再适用一些系统,如多自由度机械臂这种常采用位置控制模式的系统。该文提出了一种基于摩擦力矩—速度曲线特定区域形状分析的LuGre摩擦参数辨识法。定义形状因子来定量表示Stribeck峰和迟滞环线的形状特征,并用其辅助辨识,可得到比粒子群算法局部最优解更好的辨识结果。仿真分析和机械臂辨识实验结果表明：与纯PSO法相比,该方法的辨识实验量更小,LuGre摩擦参数辨识更准确,关节力矩预测精度更高。
The LuGre model is an advanced friction model that describes dynamic friction characteristics. However, the imported unobservable bristle deformation complicates accurate, efficient identification of the model parameters. The traditional LuGre parameter identification method requires the motion system to use torque control and requires a significant computational load. The traditional LuGre parameter identification method is not applicable to some systems, such as multiple degree-of-freedom manipulators, that use the position control mode. Therefore, this paper presents a modified LuGre parameter identification method based on an area-specific analysis of the friction torque-velocity curve. Shape factors are defined to quantify the shape features of the Stribeck peak and the hysteresis loop which are then used for the LuGre parameter identification. The identification result is better than the local optimal solution of the PSO method. Simulations and hardware identification tests on a manipulator verify the effectiveness of this method, which requires fewer experiments, has better parameter identification accuracy and more accurately predicts the manipulator joint torque than the pure PSO method.
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