Abstract: Redundant technology is a kind of important means to improve the performance of a naviga?tion system. The redundant configuration of inertial sensor in a strapdown inertial navigation system (SINS) was studied. According to the ballistic missile characteristic, inertia measuring unit (IMU) composed of three gyros with orthogonal configuration and four accelerometers with skewed configura?tion was designed for ballistic missile. firstly, it was analyzed on the main factors that influence sensor output, and the error model oi inertial sensor was built. Then, skewed configurationJ s multi-influence on sensor measurement was studied, particularly it can improve the nonlinear error greatly. On the ba?sic of the theory, a redundant configuration IMU and its calibration model were designed. The result of computer simulation shows that the IMU improves the navigation performance, the navigation pre?cision and the reliability with the available sensor precision for ballistic missile.

Key words: control and navigation technology of aerocraft , navigation , guidance and control , ballistic missile , skewed installation technology , redundant configuration , inertial sensor