Large airborne optical systems require very high beam pointing control accuracy , which will put forward some new challenges for the design of an airborne isolation platform .We analyze the characteristics of aircraft struc-tural vibration , and propose to develop a pneumatic and electromagnetic hybrid driving isolator .The isolator uses an adjustable pneumatic air spring with an external air container to suspend the payload , and a coaxial electromagnetic actuator is integrated with the output rod of the isolator , which provides a broadband active control force for the pay-load.The preliminarily determined carrying capacity is 150~190 kg and the isolation frequency range is from 1 Hz to 100 Hz.This paper firstly describes the principles of pneumatic /electromagnetic hybrid driving and presents a structural layout of the isolator .Then it simplifies the system , establishes the physical model , and derives the dy-namic equations of the isolator .Finally, the Matlab/Simulink numerical simulations of the isolator are conducted to research respectively the feasibility and efficiency of PID control algorithm and LQR control algorithms .The simula-tion results and their analysis show preliminarily that:(1) the two active control algorithms are efficient , and the payload′s vibration displacement amplitude can be reduced to ±10μm level under a wide frequency band ( 1~100 Hz) random vertical disturbance;(2) this vibration reduced performance of the isolator can meet the installation requirements of large airborne optical equipment .The comparison between the PID and LQR control methods shows that the vibration reduced performance of the PID method is slightly better than that of the LQR method for a single isolator system;besides, the PID method is easy to implement .%大型机载光学系统要求有非常高的光束指向控制精度，这将给机载隔振平台的设计提出若干新的挑战。从分析飞机结构振动特点出发，提出采用气动与电磁驱动联合作动的方法，为飞机平台设计一种适合大型机载光学系统安装的主动隔振器。单个隔振器的承载能力为150～190 kg ，垂向隔振频带范围为1～100 Hz，最大输出控制力为560 N。文中阐明了气动/电磁联合作动的运行机理，并对隔振器进行了结构详细设计；然后对隔振器进行数学模型简化，建立隔振器的动力学方程；最后利用PID控制算法和LQR控制算法，对隔振器进行Matlab/Simulink数值仿真。仿真结果表明所设计的隔振器隔振性能优异，在垂向宽带（1～100 Hz）大振幅随机扰动作用下，可以将有效载荷的振动位移控制到±10μm量级，能够满足光学设备的安装要求。 PID方法和LQR方法的控制效果对比表明，对于单个隔振器系统，PID方法较LQR方法易于实现，并且控制效果也略优。
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