An Autocollimator Axial Measurement Method Based on the Strapdown Inertial Navigation System

Area of Science:

• Optical Engineering
• Navigation Systems
• Metrology

Background:

• Autocollimators are essential optical tools for axis measurement but suffer from increased errors and limited range in non-leveled conditions.
• Existing measurement principles restrict autocollimator application in dynamic or uneven environments.

Purpose of the Study:

• To develop and validate a novel autocollimator axis measurement method capable of operating under non-leveled conditions.
• To enhance the versatility and accuracy of optical axis measurements in challenging environments.

Main Methods:

• A measurement model integrating strapdown inertial navigation system (SINS) to track autocollimator attitude changes.
• Utilizing SINS data for attitude measurement and combining it with autocollimator's angular measurements.
• Employing signal processing and data fusion in a multi-sensor system for computation.
• Conducting Monte Carlo simulations to analyze system errors and validate performance.

Main Results:

• Simulation analysis indicated that the majority of measurement errors were within ±0.002°, with overall accuracy within ±0.006°.
• Experimental tests confirmed simulation findings, showing most errors within ±0.004° and overall error within ±0.006°.
• The proposed method demonstrated consistent results between simulation and real-world testing.

Conclusions:

• The SINS-based method effectively overcomes the limitations of traditional autocollimators in non-leveled conditions.
• This approach enables precise axis measurement for autocollimators on moving bases and in dynamic environments.
• The study validates the feasibility and accuracy of the proposed measurement technique.