Digitalized Gyroscope System Based On Modified Adaptive Control Method

With the advantages of small size, light weight and low power consumption, the silicon MEMS gyroscopes have important application value and broad application prospect in both civil and military areas. After more than twenty years of development, conventional control and algorthims has been thoroughly researched. In recent years, schorlars home and abroad researched the methods of applying new control algorithms on silicon micromachined gyroscopes.In this work the possibility of applying the model refrence adaptive control algorithm into Micro-Electro-Mechanical System (MEMS) gyroscope has been investigated. Through comparing the gyroscope working condition with the reference model, the adaptive control method can provide online estimation of the key parameters and the proper control strategy for the system. The digital second-order oscillators in the reference model are substituted for two phase locked loops (PLLs) to achieve a more steady amplitude and frequency control. The adaptive law is modified to satisfy the condition of unequal coupling stiffness and coupling damping coefficient. The rotation mode of the gyroscope system is considered in our work and a rotation elimination section is added into the digitalized system. Before implementing the algorithm into the hardware platform, different simulations are conducted to ensure the algorithm can meet the requirement of the angular rate sensor, and some of the key adaptive law coefficients are optimized. The coupling components are detected and suppressed respectively and Lyapunov criterion is applied to prove the stability of the system. The modified adaptive control algorithm is verified in a set of digitalized gyroscope system, the control system is realized in digital domain, with the application of Field Programmable Gate Array (FPGA). Key structure parameters are measured and compared with the estimation results, which validated that the algorithm is feasible in the setup. Extra gyroscopes are used in repeated experiments to prove the commonality of the algorithm.