航空遥感惯性稳定平台摩擦参数辨识

摘要

In order to acquire high control precision of a three-axis inertially stabilized platform (ISP) applied in aerial remote sensing system, a method for friction parameter identification on the LuGre friction model is put forward. First, a LuGre model suitable to a three-axis ISP control system is developed based on the analysis on sine-waveform response. Then, a two-step and dynamic parameter optimization method is used to identify the friction parameters of three different frames of ISP. At last, the identification experiments are carried out to validate the method. The results show that the curves of simulated angular velocity and angular position are significantly agree with those of the experimental measurements, which illuminates that the method can accurately get the parameters of friction model of any ISP gimbals. In addition, the experiments of friction compensation are performed on the yaw-gimbal control system, and the results show that the influences of friction on control precision are significantly reduced, in which the fluctuation range and the root-mean-square(RMS) error of the angular position are decreased by 78.7%and 91.5%respectively.%针对影响航空遥感三轴惯性稳定平台控制精度的非线性摩擦，提出了一种基于LuGre模型的摩擦参数辨识方法。在分析系统正弦响应曲线的基础上，建立了适于惯性稳定平台的LuGre摩擦模型，提出了两步辨识及动态参数优化的摩擦参数辨识方法，针对惯性稳定平台三个框架系统的不同特点分别设计了参数辨识方案，最后通过实验进行了验证。结果表明，各框架角速度、角位置响应仿真曲线与实际曲线基本一致，说明提出的辨识方法能够得到各框架较为准确的摩擦模型。摩擦补偿实验结果表明，可显著降低摩擦对控制系统精度的影响，使方位系统角位置误差波动范围、角位置跟踪均方根误差比未补偿前分别减少了78.7%和91.5%。