无人机气液压发射动力学数值仿真

Dynamic Numerical Simulation of the Pneumatic and Hydraulic Launching of UAV

气液压发射起飞是近年来国际上出现的一种先进的中小型无人机发射方式,以气液压能源提供动力实现无人机发射起飞。基于气液压系统原理,对蓄能器气体弹簧的弹性系数进行分析,建立由气液压系统动力学模型、增速滑轮组动力学模型、无人机及滑车的运动方程构成的发射过程动力学模型,并进行仿真计算和数值分析,分析结果表明无人机及滑车质量、蓄能器充油压力、液压缸活塞有效面积、蓄能器容积是影响发射过程和起飞速度的关键参数,在一定范围内通过调节气液压系统参数可适应于不同的无人机起飞质量和起飞速度要求。采用与试验结果比对的方法修正气液压系统的总粘性阻尼系数,将仿真结果与试验结果进行对比研究,研究结果表明仿真计算结果与试验结果表现出较好的一致性,证明了发射过程动力学模型的正确性,为无人机气液压发射装置的工程研制提供了重要的理论参考。

The takeoff by pneumatic and hydraulic launching is an international advanced launching technology of medium and small unmanned aerial vehicles（UAV） recently.The power for launching comes from pneumatic and hydraulic energy.The elastic coefficient of accumulator gas spring is analyzed on the basis of the principle of pneumatic and hydraulic systems.The dynamic models of launching process are built and simulated,including dynamics models of pneumatic and hydraulic systems and pulley block system and movement equations of UAV and shuttle.The results of simulative calculation and numerical analysis indicate that the mass of UAV and the shuttle,the accumulator volume and oil charge pressure and the effective area of hydraulic cylinder piston are the key parameters affecting launch process and takeoff velocity.Moreover,adjusting the parameters of pneumatic and hydraulic systems within a certain range can adapt to different requirements of takeoff mass and velocity of UAV.The total viscosity damp coefficient of pneumatic and hydraulic systems is corrected by comparing with the experiment result.The result of simulation is in good accordance with that of experiment,which proves the correctness of the dynamic models of launching process,thus providing an important theoretical reference for the development of pneumatic and hydraulic launching equipment of UAV.