The Hexapod micro-vibration system contains some self-contradictory technical specifications: the heavy load and the small order of vibration magnitude. In view of this fact, an automatic leveling pneumatic support system is designed for precisely unloading the dead weight and for the small order control of the actuators. The system consists of the four-point trapezoidal resilient mounting system with air springs when the system is in the work state, and the three-point stiff auxiliary mounting system for load support when the system is not in the work state. The automatic leveling control system has two features: the force coupling between the resilient mounting and the stiff mounting, and the non-linearity and the time-delay of the pneumatic control. To solve these two problems, an switch on-off control scheme including the continuous inflation and the pulse inflation is proposed. The experiment results show that the Hexapod system with a load of 200kg can be automatically leveled within 140s, and the displacement errors of the Hexapod's six actuators are less than or equal to 1mm.%Hexapod微激振平台具有负载重量大和振动量级小的特点,为了实现精确卸载、作动器小量级精密控制,研制了基于空气弹簧支撑的Hexapod微激振平台.该平台包括负责工作状态承载的4点梯形分布的空气弹簧柔性支撑和负责非工作状态承载的3点刚性辅助支撑两部分.针对该平台自动调平控制的两大问题:即柔性支撑与刚性支撑之间存在的力耦合以及气路控制中存在的非线性和时延性,提出了连续充气和脉冲充气相结合的开关控制策略.为验证自动调平控制的可行性,在负载重量约为200 kg的Hexapod微激振平台上进行试验,结果表明,平台可在140 s内实现自动调平,且6个作动腿位移误差不超过1 mm.
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