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A high precision instrument to measure angular and binocular deviation introduced by aircraft windscreens by using a
B N Shivananju1, S Yamdagni, R M Vasu
1Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012, India.
The Review of Scientific Instruments
|January 3, 2013
Summary
Transparent sheets cause visual distortion, impacting pilot decisions. A new instrument accurately measures angular and binocular deviations in aircraft windscreens and canopies, enhancing flight safety.
Area of Science:
- Optical Engineering
- Aerospace Engineering
- Metrology
Background:
- Transparent materials with surface irregularities cause optical distortion, affecting visual perception.
- Angular and binocular deviations are critical safety parameters for aircraft windscreens and canopies.
- Existing methods may lack the precision required for qualifying aerospace transparent components.
Purpose of the Study:
- To develop and validate an instrument for precise measurement of angular and binocular deviations.
- To provide a tool for the accurate qualification of aircraft windscreens and canopies.
- To enhance aviation safety by ensuring the optical integrity of transparent components.
Main Methods:
- Utilizing a periodic dot pattern illuminated through the transparent specimen.
- Measuring deviations by comparing the specimen's geometrical shadow pattern to a reference pattern.
- Employing cross-correlation techniques to quantify pattern shifts and determine deviations.
Main Results:
- The developed instrument accurately measures both angular and binocular deviations.
- Achieved accuracy is less than ±0.1 mrad (approximately 0.036 mrad).
- Demonstrated excellent repeatability with an error margin below 2%.
Conclusions:
- The novel instrument effectively quantifies optical deviations in transparent sheets.
- This technology is crucial for the rigorous qualification of aircraft windscreens and canopies.
- Improved measurement accuracy contributes to enhanced pilot decision-making and aviation safety.
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