Self-Calibration Method for Circular Encoders Based on Inertia and a Single Read-Head
Xiaoyi Wang1,2, Longyuan Xiao1, Kunlei Zheng1
1School of Mechatronics Engineering, Henan University of Science and Technology, Luoyang 471003, China.
Sensors (Basel, Switzerland)
|May 25, 2024
Summary
A novel self-calibration method for circular encoders utilizes inertia and a single read-head to significantly reduce angle measurement errors. This approach enhances accuracy and repeatability for precise angular positioning systems.
Area of Science:
- Metrology
- Mechanical Engineering
- Instrumentation
Background:
- Circular encoders are crucial for precise angle measurement in various industrial applications.
- Existing calibration methods can be complex, time-consuming, or require specialized equipment.
- Inaccuracy in angle measurement can lead to significant performance degradation in controlled systems.
Purpose of the Study:
- To develop a novel, self-calibration method for circular encoders.
- To improve the accuracy and repeatability of angle measurements.
- To reduce reliance on external calibration equipment and procedures.
Main Methods:
- Utilizing inertia and a single read-head for self-calibration.
- Fitting encoder velocity curves with polynomials.
- Applying the principle of circle closure and angle interval periodicity.
- Implementing an iterative method to enhance calibration accuracy.
Main Results:
- Experimental verification confirmed the method's feasibility.
- Significant reduction in angle measurement error from 239.343" to 11.867" (peak-to-peak).
- Excellent repeatability of calibration results, with a value less than 2.77".
Conclusions:
- The proposed self-calibration method effectively compensates for angle measurement errors in circular encoders.
- The method offers a practical and accurate solution for improving encoder performance.
- This technique has the potential to enhance the reliability of angular measurement systems.
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