【作者】 郭建华；

【导师】 王辉；

【作者基本信息】 中国民航大学 ， 人机与环境工程， 2008， 硕士

【摘要】 飞行模拟器中的操纵负荷力加载伺服系统是一典型的位置扰动型施力系统,它要求施力系统根据被加载对象(驾驶杆)位移的大小给驾驶杆施加相应的力。由于位置扰动,施力系统会产生一个很大的力干扰,即多余力,如果处理不当,这种多余力会比系统所要施加的力还要大。多余力的存在,将影响力伺服系统的跟踪精度,进而影响加载系统的品质。操纵负荷力加载系统的品质会极大地影响到操纵负荷系统对驾驶杆力的仿真效果,从而影响整个飞行模拟器的品质。本文以飞行模拟器中的操纵负荷系统为研究背景,对位置扰动型电液伺服力加载系统进行了深入的研究。建立了操纵负荷力加载系统的数学模型,重点分析系统中由于位置扰动而产生的多余力问题、电液伺服阀非线性问题、以及液压缸摩擦力对系统性能的影响,并针对这些问题提出相应控制策略,进行误差补偿。针对系统的多余力问题,本文采用结构不变性原理进行补偿;针对电液伺服阀的非线性因素及负载流量的时变性,采用改进型结构不变性原理与PID结合的复合控制策略进行误差补偿;针对液压缸摩擦力问题,则基于LuGre模型和状态观测理论设计了摩擦力状态观测器。仿真结果表明,结构不变性原理能够有效的抑制多余力;电液伺服阀的非线性因素对系统产生了显著的影响;将结构不变性原理进行改进后与PID结合,可以较好抑制多余力的产生,但对非线性因素引起的实际输出力曲线振荡现象无法完全消除;对系统进行摩擦补偿,可以进一步降低系统输出误差,提高系统的跟踪精度。更多还原

【Abstract】 The force loading control servo system of flight simulator is a typical position disturbance type of force loading system. In this system the corresponding force needed to the pilot stick should be loaded according to the displacement of stick. Due to the motion of object, a high displacement disturbance would be produced, called as extraneous force, which could be larger than the need force if correct treatments are absent. In many cases, the extraneous force will reduced the precision of the system. The extraneous force will affect track precision of the system. The quality of the force loading control system will have a great impact on the effect of simulation to the pilot stick, and then the quality of the flight simulator.With the background of control loading system of flight simulator, the position disturbance type of electro-hydraulic servo force loading system is studied deeply in this thesis. A mathematical model of force loading control system has been established. And then analyses are placed on the extraneous force due to position disturbance, non-liner of electro-hydraulic servo-valve and the impact of friction of hydraulic cylinder. Aiming at these factors, controlling strategies were put forward to compensate them.For the problem of extraneous force, the structure-invariable principle is used for compensation. And with a hybrid control strategy of the improved structure-invariable principle and the Proportional-Integral-Differential (PID), errors of the electro-hydraulic servo-valve’s non-liner and real-time of the load flux are compensated. With regard to the hydraulic cylinder’s friction force, a friction observer is designed based on LuGre model and theory of state observation. The simulation results indicated that the extraneous force can be restrained effectively by the structure-invariable principle; the non-liner factor of electro-hydraulic servo-valve has a great impact on the system; and the combination of improved structure-invariable principle with PID could cut down extraneous force sharply, but do not have a remarkable effect on reducing track error resulting from non-liner factor; and that compensating system for the friction could further reduce output error and improve the track precision of system.更多还原