一种新型大过载飞行模拟器运动仿真分析

Motion Simulation of a New High Overload Flight Simulator

提出一种新型的基于绳牵引并联机器人技术的飞行模拟器,针对其大过载机动特性进行仿真分析。首先根据绳牵引并联机器人理论,设计了9根绳牵引具有6自由度的运动平台;通过建立平台动力学模型,设计了对干扰项进行补偿的前馈PD控制率;其中前馈项主要确保动态过程中绳索处于张紧状态。进一步给出了系统控制稳定性分析;并以大过载机动和单自由度俯仰振荡运动为例进行了数值仿真。分析结果表明,在大过载机动情况,瞬时正加速度超过4 g,平台位置能够迅速衰减并稳定;基于绳拉力前馈,可以避免绳索松弛,能够满足飞行员过载训练;俯仰运动也具有较好的跟踪特性。研究成果可为进一步分析工作空间、动态特性及控制稳定性等奠定基础,为绳牵引并联支撑的飞行模拟器设计提供指导与依据。

A new kind of flight simulator based on the cable-driven parallel robot was proposed, and the over-load maneuver properties were emphatically analyzed. According to the fundamental theories of cable-driven parallel robot, the motion platform suspended by nine cables with a six-DOF is designed. The dynamic equations of the platform is established, and a PD control law incorporating feedforward term and disturbance compensation term is given. The stability analysis of control law is also made. Finally, numerical simulations of overload maneuver and pitch oscillation are taken as examples, and results show that the platform can achieve a high overload with more than 4 g, meanwhile the position attenuates and tends to be stable in a short time. The cable tension is also guaran-teed to be positive and secure during the motion process. Moreover, the case of pitch oscillation shows a good track-ing property. Researches studied above could lay on foundation for the workspace analysis, dynamics and control stability, and furthermore, provide guidance and evidence for the practical design of flight simulator.