Error analyses and calibration methods with accelerometers for optical angle encoders in rotational inertial...

Area of Science:

• Navigation Systems Engineering
• Sensor Calibration Technologies
• Optical Metrology

Background:

• Strapdown inertial navigation systems (INS) benefit from rotation to mitigate sensor errors.
• Rotational INS (RINS) performance is critically dependent on accurate rotary angle measurements.
• Existing calibration methods face limitations due to hardware constraints and cost.

Purpose of the Study:

• To develop advanced calibration methods for single-axis RINS using optical angle encoders.
• To address the limitations of current gyroscope-based and multireadhead calibration techniques.
• To enhance the overall accuracy and reliability of RINS.

Main Methods:

• Proposed novel optical angle encoder calibration methods utilizing accelerometer data.
• Conducted navigation error and accuracy requirement analyses for single-axis RINS.
• Implemented and tested the proposed calibration techniques on a rotational INS.

Main Results:

• Achieved calibration accuracy exceeding 4 arcsec (1σ) with the proposed methods.
• Demonstrated superior performance compared to existing calibration approaches.
• Validated the effectiveness of accelerometer-based optical angle encoder calibration.

Conclusions:

• The developed optical angle encoder calibration methods offer a significant improvement in RINS accuracy.
• These methods provide a viable and accurate alternative to traditional calibration techniques.
• The findings are crucial for advancing the performance of rotational inertial navigation systems.