Artificial Targets Match And High-speed Calculation Of Self Calibration Bundle Adjustment In Digital Industrial Photogrammetry

Digital industrial photogrammetry based on digital images is one of high accuracy 3-D measurement techniques. The precision measurement of article targets image coordinates, the auto-match of targets and self-calibration bundle adjustment are key techniques for automatic and high accuracy measurement.The paper researched some of key techniques in digital industrial photogrammetry, including the auto-match of article targets, the deviation model of camera and the high-speed calculation of self-calibration bundle adjustment. The main contents of the paper are following.The characteristic of digital industrial photogrammetry was expatiated in the paper. Domestic and overseas development and state of digital industrial photogrammetry system were introduced. The key techniques in digital industrial photogrammetry system were analyzed.The theory of article targets match basing on epipolar lines was introduced. A new match method based on space intersection was described in the paper. Its high speed and accuracy and the accurate result as initial values of self-calibration adjustment were validated by experiments.The paper analyzed the deviation character of digital camera, and calibrated it with 10 parameters model. Some experiments validated that the model could calibrate the systemic imaging errors.According to the character of digital industrial photogrammetry,a speedy calculation of self-calibration bundle adjustment based on point relaxation method was described. Some experiments validated that its speed was much high than the simultaneous calculation, while its precision was equal to the latter, and it could treat with the data in field measurement.The corresponding function modules of match and adjustment were developed , and applied successfully in the measurement of an antenna with the diameter of 17.2m on a satellite, with their validity and reliability were validated.