Precise measurement for line structure light vision sensor with large range.

Area of Science:

• Metrology
• Computer Vision
• Optical Engineering

Background:

• Three-dimensional scanners aim for high precision and large measurement ranges.
• Calibration of line structure light vision sensors is crucial for measurement precision.
• Existing calibration methods often yield locally optimal solutions, limiting precision across large ranges.

Purpose of the Study:

• To develop a precise measurement method and calibration procedure for line structure light vision sensors.
• To achieve high precision measurements over a large working range.
• To improve upon traditional measurement techniques by eliminating distortion compensation and enhancing accuracy.

Main Methods:

• Utilized a motorized linear translation stage (150 mm travel range) and a precision planar target (0.05 mm machining precision).
• Established functions relating laser stripe center points to perpendicular/horizontal distances using the translation stage and target.
• Obtained precise measurements from normalized feature points after capturing laser stripe images.

Main Results:

• The proposed method achieved significant precision improvement compared to traditional approaches.
• Root mean square error was reduced by 64.67% relative to the traditional measurement method.
• Distortion compensation was rendered unnecessary with the new technique.

Conclusions:

• The developed method provides a precise calibration for line structure light vision sensors.
• The technique enables high-precision measurements across a large working range.
• This approach offers a substantial improvement in measurement accuracy and efficiency.