Constant Tension Device Of Pneumatic

With the rapid development of Aerospace Engineering, new spacecraft ground test equipment also continuously put forward new requirements, especially for the zero-springrate suspension system. The zero-spring-rate suspension system can simulate zero gravity environment of space to deploy and modal test in multi-dimensional. For realizing the free boundary condition of movement, low frequency hanging device must have a very low stiffness whit longer stroke and low inertia.The original zero-spring-rate suspension system for flexible solar wing vibration modal test just need a short stroke because of small amplitude of vibration, and for the one-dimensional vibration without hanging point to follow. In order to meet the need of the Research Institute of satellite antenna deployment for multidimensional suspension test equipment, it is necessary to design a new zero-spring-rate suspension system whit long stroke and low inertia.The main work and achievements are as follows:1. Discuss the advantages and disadvantages of three kinds of common execution unit,and combined with the suspension device, expounds the pneumatic system in the zerospring-rate suspension system application advantages.2. Design of a mechanical device has a more simple mechanical structure, the output supply by a single non-friction cylinder whit gas lubrication to achieve high accuracy constant suspension force; the design of the new structure of the frictionless cylinder whit a new piston and air bearing, supply by the same pressure gas cylinder can improve the internal orifice plug,which has better lateral resistance. Design of motor active following equipment virtual overall stroke extended cylinder.3. The fluent simulation of air static pressure lubrication, explained the mechanism of orifice compensated hydrostatic lubrication cylindrical lateral capacity, discussing the key effects of various parameters on the lateral capacity. The diameter of the throttle Orifices is the key parameter, discusses the corresponding relation between each parameter and the orifices diameter. The key element is the relationship between the average thickness of the gas film and orifices diameter for the static pressure lubrication performance.In this paper the most important work is the design of mechanical structure and a new fluent simulation which can through the visualization of the pressure distribution to show the change of the pressure distribution generated by gas lubrication parameters. The device cannot only simulate the zero gravity environments, also can simulate the environment of lunar surface. The processing of the cylinder and the piston is very demanding, so we need to study the processing technology of circumferential inner surface, improve the roundness and surface finish make the performance of frictionless cylinder improve.