Design and Research on Stabilization Loop of Gyro Stabilized Pod Control System
|School||Harbin Institute of Technology|
|Course||Control Theory and Control Engineering|
|Keywords||gyro stabilized platform stabilization loop frequency response method model-reference self-adaptive control|
In recent years, gyro stabilized pod has been widely applied in both military and civil fields, such as public security, fire fighting and environment monitoring. Stabilization loop, a key component of the pod’s control system, is designed to isolate disturbance yielded by carrier and to compensate the friction torque, so LOS can be stabilized. The work of this paper is focused on the stabilization loop.First, the status quo of gyro stabilized platform development in both China and abroad is summarized and then conventional LOS stabilization control structures and methods are introduced. Later, based on the structure configuration of the gyro stabilized platform used in this paper, the disturbance-counteraction principal of a two-axis stabilized platform and disturbance-counteraction performance of a two-axis four-frame stabilized platform are derived and analyzed respectively, contributing to the establishment of a math expression for the stabilization loop. Then, different factors affecting the LOS stabilization are analyzed, providing a foundation for the control algorithm.While programming the control algorithm, frequency response method is applied in designing the stabilization controller to counteract disturbance from exterior carrier. Simulation results show that the controller could meet the stabilization precision requirement in terms of disturbance rejection. Self-adaptive control based on Coulomb Model is applied to make compensation for major impact yielded by friction torque. Simulation results demonstrate that the method could fulfill its task satisfactorily by reducing spikes of the LOS shake’s velocity curve and eliminating low velocity jittering; besides, using this method, the stabilization precision is further improved. The wavelet threshold-value filter is applied to de-noise the MEMS gyro. Simulation results show that the standard deviation of noise reduces obviously and the noise of gyro is restrained effectively.In the last part of the paper, device selection for the stabilization loop’s hardware circuit is introduced and corresponding peripheral circuit is designed. Then, the hardware circuit is built up on the printed circuit panel for the stabilization loop, bringing the control algorithm into physical use.