Automatic Ball-Pressure Indentation Testing System Based on Image Processing Technology

Ball Pressure test is an important experiment which assesses the heat endurance of thermoplastic materials in lots of product safety standards, and it is also often used in laboratory proficiency testing experiment. The test result is determined by the valid diameter of indentation at the tangent points, not the complete indentation. At present most tests are based on experience, and are subjected to various problems due to personal difference. In view of this, this paper presents a measurement based on visual inspection and digital image processing.This method is to get a clear picture of the indentation through the optical information transform system and the CCD camera. And non-contact distinguish, automatic completion of measurement, real-time generate the test reports for different situations. Experiments show that the method has a relatively high degree of automation, small man-made error, test results with high accuracy and Repeatability.