Attitude Switching Control of Stereo Imaging Small Satellite with Multi Actuators

Currently, the functional requirement of optical small satellites is increasing. The operation mode of track stereo imaging is an important one of optical small satellites, which is in the same orbital period, the optical load image the same target area from the front and behind directions to generate stereoscopic image. This requires the small satellites made rapid large angle maneuver with increasing frequency, and have the high precision steady state after the maneuver. Therefore, the requirements of satellite attitude control system are not only a high bandwidth, but also have higher control accuracy. Control moment gyroscope (CMG) is a large torque actuator than the flywheel torque actuator, and it can provide a higher precision control. Application of symmetrical CMGs and flywheel group to control of small satellite attitude, it can achieve fast and high precision attitude motion, and complete the process of track stereo imaging. The joint control of this method needs the switching stability of two kinds of actuators, which means it has to plan and design the actuator torques, such that the effect of switching between CMGs and flywheel is minimal. In this paper, the switching algorithm is designed, which needs to plan the gimbal angular of CMGs, to solve the problem of switching unstable between two kinds of actuators. The Simulation results show that the maneuvering speed is fast, the good stability and smooth switch process of are achieved.