A new multi-position calibration method for accelerometers of the inertial navigation system

摘要

To guarantee success of precision navigation, it is necessary to carry out in-field calibration for the accelerometers of the inertial navigation system (INS) before a mission is launched. Traditional multi-position calibration method for accelerometers of the inertial measurement units (IMU) are carried out through a turntable (Strap-down INS) or the gimbals(platform INS). To achieve high precision calibration results, the position of the turntable (gimbals) need to be locked precisely. However, the high precision positions are difficult to be attained outside the laboratory. Focusing on this problem, a new calibration method is proposed which uses the gravity residual to reduce the effects caused by locking errors of the positions. Simulations are conducted to analyze the performance and the sensitivity of the proposed methods. It is proved that the proposed methods can estimate the accelerometer parameter more precisely than traditional multi-position methods.