Workpiece curvature detection system and method

Abstract

The invention discloses a workpiece curvature detection system and method. The system comprises a sensor and a data processing module, wherein the data processing module comprises a segmentation module, a curvature rough measurement module and a curvature accurate measurement module. The sensor is used for collecting data of a plurality of discrete points on the plane and the curved surface, and projections of the plurality of discrete points on the plane are on the same straight line. The segmentation module is used for segmenting the plurality of discrete points into a set of discrete pointson a straight line and a set of discrete points on an arc line. The curvature rough measurement module is used for calculating an arc circle parameter range in combination with a geometric method anda least square circle fitting method and taking the arc circle parameter range as a parameter space search range of a Hough transform method. The curvature accurate measurement module is used for obtaining an actual curvature parameter space of the arc by adopting a Hough transform method and calculating a curvature accurate value of the arc by using a probability model. The system provided by the invention has the advantages of small noise influence, strong robustness and more accurate measurement.

Description

technical field [0001] The invention belongs to the technical field of precision measurement, and more specifically relates to a workpiece curvature detection system and method. Background technique [0002] At present, smart phones have become a necessity of life, and their designs are becoming more and more beautiful. 3D glass has become the mainstream material for mobile phone covers because of its beauty and strength. Now that mobile phone manufacturing is becoming more and more sophisticated, higher requirements are put forward for the tightness of the connection between various parts, especially for large structural parts such as the cover plate, how well the various parts of the surface are combined with the main structure, It has a great influence on the beauty, feel, waterproof, durability and other aspects of the mobile phone. In particular, the curved edge of the glass cover is a key part that affects the precision of the combination of the cover and the host. Th...

AI Technical Summary

Problems solved by technology

For curvature calculation, the main methods currently used are the least squares fitting method and the Hough variation method. Among them, the least squares fitting circle method is greatly affected by noise, and the Hough transformation method requires manual work in advance to determine the search range of the parameter space. Sure, if the selection range is too large, the calculation time will be long and the search efficiency will be low; if the setting is too small, the optimal value may be missed

Moreover, only the parameter value corresponding to the maximum vote value is selected as the detection result. When the sampling points are relatively small, the noise will have a greater impact on the measurement results.

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