Investigation On The Control System Of The Rate-biased Platform For The Laser Gyro

With the development of inertial technology, laser gyro has been widely applied in the Inertial Navigation System (INS). But it can't be used in the system until some bias technology is used to overcome the lock-in of the laser gyro. Among all kinds of bias technology, the rate-biased technology can decrease the random walk error and improve the accuracy of the laser gyro. The rate-biased platform and its control system are the important parts of the rate-biased system.In the paper, an experimental system researching on rate-biased technology with single-gyro is designed and implemented. The hardware of the control system has been designed based on the TMS320F2812, which is a digital signal processor developed by the company of TI. And the L298 is a high voltage, high current dual full-bridge driver. The drive circuit and the protection circuit have been designed properly with the two chips, and they make the hardware of the system credible and safe. The angular position and the angular velocity which are detected by the high-accuracy encoder will be sent to the DSP as the feedback signal of the control circuit.Considering the requirement of the control system, the frequency-domain design is adopted. The theory of this method is mature, and it is suited to the linear system such as the control system of the motor. The measurement method of the frequency characteristic is analyzed with the Fourier transform. The control scheme can be designed completely based on the frequency characteristic of the rate-biased platform. The simulation results of the control system are helpful to choose the right controls parameters. At last, some experiment is conducted, and the results show that the system works well as it was expected.