柔性悬吊平台光电系统动力学分析

Dynamics Analysis of Opto-electronic System Fixed on Soft-rope Hanged Platform

提出了一种基于地平式光电经纬仪并带有姿态稳定装置的柔性悬吊平台光电系统的结构，以实现精密指向。根据系统各部件之间的运动学关系，采用通路矩阵、约束力元矩阵等方法描述了系统的拓扑构型。采用拉格朗日方法建立了系统的多刚体动力学模型。仿真实验研究了平台绕垂线的转动以及垂线一地平面内的摆动对视轴指向精度的影响。仿真结果：若系统沿垂线方向的转动惯量在lO。kg．rn。量级、反捻机构残余力矩10之N．m的量级，方位轴的控制指向精度与光电传感器的分辨率精度相当，可以达到10^-5rad。如果缆绳的长度在10m数量级，系统绕摆动轴的转动惯量将达到10^5～10^7kg·m^2量级。平台的摆动幅度在0．017rad时，视轴的指向控制精度可以控制在10^-4rad量级。仿真结果表明：反捻机构开启、光电系统指向控制能力强时，可以不对平台进行姿态控制。另外，摆动将造成经纬仪两个轴系的耦合。

In order to achieve opto-electronic system precision pointing, a structure of horizontal opto-electronic system, which was fixed on soft-rope hanged platform with attitude stabilizing device, was presented. According to the kinematics relationship of the parts of this system, some methods were employed to describe the topological configuration of the system, such as matrix of channel vector and matrix of constraint force element. Friction tqrqug~ platform attitude control torque and other disturbance torques were discussed. Lagrange method was used to establish the multi-body system dynamics model. Simulations were performed to study the influence caused by random rotation of the platform in the azimuth axis and pendulum in the plumb-horizon plane to the Line of Sight （LOS） pointing accuracies. It can be concluded that platform attitude controller is unnecessary when pointing controller is strong and the anti-twist system works well. Furthermore, pendulum would lead to coupling of azimuth angle and horizontal angle of LOS.