Self-Alignment MEMS IMU Method Based on the Rotation Modulation Technique on a Swing Base

Area of Science:

• Engineering
• Navigation Systems
• Sensor Technology

Background:

• Micro-electro-mechanical-system (MEMS) inertial measurement units (IMUs) are crucial for inertial navigation due to their compact size and low cost.
• Conventional IMU alignment methods require static bases and auxiliary sensors, limiting their application range.
• Accurate alignment of MEMS IMUs under dynamic or swing conditions is a significant research challenge.

Purpose of the Study:

• To develop a self-aligned method for MEMS IMUs capable of operating on a swing base.
• To mitigate the impact of inertial sensor errors during dynamic alignment.
• To improve the overall alignment accuracy of MEMS IMUs in non-static environments.

Main Methods:

• Implementation of the rotation modulation technique (RMT) for complete self-alignment.
• Application of RMT-based inertial frame alignment (RMT-IFBA) for coarse alignment on a swing base.
• Utilization of a strong tracking filter (STF) to refine alignment precision.

Main Results:

• The proposed RMT-based method achieved self-alignment on a swing base, eliminating the need for external sensors.
• The strong tracking filter effectively enhanced the accuracy of the alignment process.
• Experimental validation demonstrated low standard deviations for pitch (0.0140°), roll (0.0097°), and heading (0.91°).

Conclusions:

• The developed rotation modulation technique offers a practical and effective solution for self-aligning MEMS IMUs on dynamic bases.
• This method significantly improves alignment accuracy compared to conventional techniques in challenging conditions.
• The findings highlight the potential for wider application of MEMS IMUs in dynamic inertial navigation systems.