Visual encoder-based angle measurement method in low-frequency angular vibration calibration.

Area of Science:

• Mechanical Engineering
• Instrumentation and Measurement

Background:

• Angular vibration calibration is crucial for sensors like gyroscopes and accelerometers used in engineering.
• Current angle measurement methods (laser interferometry, circular grating) are often complex, costly, or limited in range.

Purpose of the Study:

• To introduce and validate a novel, simple, and flexible angle measurement method for angular vibration calibration.
• To address the limitations of existing high-cost or range-restricted calibration techniques.

Main Methods:

• Development of a novel angle measurement technique combining a special visual encoder and accurate angular position detection.
• Utilization of a telecentric vision measurement system for a simplified setup.
• Comparative experiments against the established circular grating (CG) method.

Main Results:

• Static angle measurement deviations of 0.0014° (small-angle) and 0.0138° (full circle).
• Angular vibration measurement relative deviation below 0.173% (0.1-8 Hz, 0-100° amplitude).
• Calibrated gyroscope sensitivity relative deviation less than 0.096% compared to CG method.

Conclusions:

• The novel visual encoder method provides accurate and reliable angle measurements for vibration calibration.
• This technique offers a simpler, more flexible, and cost-effective alternative to traditional methods.
• The validated performance supports its application in calibrating dynamic inclinometers, gyroscopes, and angular accelerometers.