Mechanism and Implementation of Error Suppression in MEMS INS via Rotational Modulation and Array

Abstract To enhance the accuracy of Micro Electro-Mechanical System (MEMS) inertial navigation systems (INS) without using additional sensors, we propose a Rotational and Arrayed Inertial Navigation System (RAINS) that compensates for both stochastic and deterministic MIMU errors through sensor array configuration and rotary modulation techniques. In this paper, the RAINS’s suppression effects of MIMU’s deterministic error and stochastic errors are analyzed. According to the mechanism analysis, the fusion method of MIMU array based on Minimum Norm Quadratic Unbiased Estimation (MINQUE) method and error similarity degree is adopted, which improves the fusion accuracy and stability of MIMU array. Furthermore, an optimization scheme for rotational modulation is proposed, which further improves the accuracy of MEMS inertial navigation system. In this paper, the prototype of RAINS was developed and the experiments were carried out. The test results show that the developed RAINS improves the horizontal positioning accuracy by more than 70% compared with the MEMS INS. It proves that the RAINS, fusion method and modulation scheme proposed in this paper can effectively suppress the error of MEMS INS.