关键词: 微机电系统(MEMS)陀螺, 陀螺阵列, 最优定界椭球(OBE)算法, 数据融合, Chebyshev中心

Abstract: In order to improve the accuracy of micro-electro-mechanical system (MEMS) gyro, an optimal bounding ellipsoid (OBE) algorithm based on relaxed Chebyshev center (RCC) is proposed and used to fuse gyro array signals. On the basis of the error model of single gyro, the maneuvering fusion model of the array system is established. Because of the uncertainty of the noise statistics, the accuracy of the traditional fusion method is reduced. The set-membership estimation theory with unknown but bounded disturbances is introduced and the OBE algorithm is used to achieve the robust estimation of the angular rate. In the OBE algorithm, the ellipsoid geometry center is often used as the point estimate of the true value, but it is not optimal theoretically. The Chebyshev center of the feasible set has many excellent features. Meanwhile, considering that it is very difficult to solve the exact Chebyshev center, the relaxed Chebyshev center is used as a substitute for the point estimate of the true angular rate. Then an OBE update process with RCC as output is designed and a novel parameter optimization criterion is proposed. The verification experiment is performed by using a gyro array composed by six gyroscopes. The experimental results show that the estimation fusion method based on the proposed algorithm can obtain the angle rate guaranteed boundary and further improve the MEMS gyroscope accuracy.

Key words: micro-electro-mechanical system (MEMS) gyro, gyro array, optimal bounding ellipsoid (OBE) algorithm, data fusion, Chebyshev center