Parameter identification for the LuGre friction model based on an area-specific shape analysis of the friction torque-velocity curve

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.