Vision measurement method for impact point in large planar region

On the basis of summarizing the methods of camera calibration, a new method of direct geometric solution (DGS) based on calibration objects is proposed. It is required to establish some beacons in particular position with equal height in measurement area. Adjust camera carefully to ensure that the measurement plane is orthogonal to the image plane of the camera. The DGS model which is used to calculate the coordinates of points in measurement area is built with the pinhole imaging model and the coordinates of calibration objects. The comprehensive error caused by measurement error was simulated in MATLAB with DGS model, and the experiment of actual measurement was done. The experiment data was processed respectively by the DGS model and the DLT (direct linear transformation) model. The results show obviously that both the accuracy and error stability of DGS are better than ones of DLT. The average relative error of DGS in this experiment is 0.5%. The DGS model is better than the DLT model in locating the impact point in remote large area.