Direct calibration method of laser stripe vision sensor based on gauge block

作者：Zou, Yuanyuan; Zhao, Mingyang; Zhang, Lei

来源：CHINESE JOURNAL OF LASERS-ZHONGGUO JIGUANG, 2014, 41(11): 1108002.

DOI：10.3788/CJL201441.1108002

• Direct Calibration Method
• Gauge block
• High-accuracy measurements
• Least-square fitting
• Measurement accuracy
• Model-based calibration
• Three dimensional coordinate
• Vision sensors

The calibration accuracy of laser stripe vision sensor is directly related to accuracy in measurement. The commonly adopted calibration method is model-based calibration method. The model will become significantly complicated and the calculation will become complex when a high measurement accuracy is required. In order to calibrate the laser stripe vision sensor with high accuracy, high efficiency and low cost, a direct calibration method for laser stripe sensor based on gauge block which does not require model is proposed. Firstly, a calibration target is designed. Secondly, a lookup table of the direct mapping relationship between image coordinates and three-dimensional coordinates of feature points is built. Finally, three-dimensional coordinates of an arbitrary point can be obtained from the lookup table directly or with least-square fitting algorithm. Experimental results demonstrate that this direct calibration method has high accuracy. Its average absolute measuring accuracy is 0.0279 mm in y direction and 0.0237 mm in z direction. It concludes that this method can meet the requirements of high accuracy measurement, and the calculation is simple and easy to implement.

• 出版日期2014-11-10