Configuration Optimization in Miniature Interferometric Fiber-Optic Gyroscopes for Space Application

With the development of small satellites, the space-borne interferometric fiber-optic gyroscopes (IFOGs) need to satisfy the requirements of high reliability, light weight and small size. Traditional multiple-axis redundant configurations are no longer applicable for miniature IFOGs. In this paper, a novel configuration reliability optimization method is presented for IFOGs, whereas limiting weight and volume. Firstly, a fault tree analysis for the space-borne single-axis IFOG is carried out and the effects of the space environment on IFOG components are discussed. Then, based on the failure features and performance degradation characteristics of the IFOG components, the reliability model is deduced. The configuration reliability optimization method is proposed for the first time to achieve high reliability of space-borne IFOGs, without increasing weight and volume. Traditional four single-axis IFOG configuration is employed to verify the effectiveness of the proposed method, the optimized results show that with our experimental IFOG parameters, the reliability is improved by 2.3%-3.1% in the first year, 21.4%-22.1% in the third year and 53.9%-55.0% in the fifth year, whereas the total weight dropped by 8.3% and the total volume is almost same. Therefore, the proposed method is efficient and easy to implement, which actually has been used in prototypes and products.