Method of high precision pointing control for spacecraft system based on the active-passive integrated orthogonal micro-vibration isolation platform

Abstract

To acquire the high precision pointing control for spacecraft system under the disturbance of micro-vibration, and resolve conflicts between the vibration suppression and pointing control, a simultaneous-distributed control method was proposed in this paper. Based on this method and the Stewart platform, an active-passive integrated orthogonal micro-vibration isolation platform with multiple dimensions was developed. Six line-actuators according to the configuration of Gough-Stewart parallel mechanism were selected to build the platform. Specially, the displacement of the line-actuator was converted from the end deflection of two groups of active and passive integrated cantilever beams, which contained viscoelastic damping plate, aluminum material and macro fiber composite (MFC). It should be noted that the dynamic model of the platform system was strongly coupled and it was decoupled by employing the orthogonal configuration. By employing the simultaneous-distributed control strategy, the integrated control algorithm of vibration isolation and pointing was deeply studied. Furthermore, the dynamic behavior and control effects for the 6 degree of freedom (6-DOF) Stewart platform with different control strategies were compared and analyzed. Results showed the method had a good vibration isolation effect and reliable pointing accuracy, which could be applied for the spacecraft requiring high precision pointing.