Research On Calibration Methods Of Binocular Measurement Systems In Non-overlapping Fields Of View

With the continuous development of smart manufacturing and machine vision technology,vision measurement methods that enable non-contact,high-precision real-time measurement have led some academic boom.Currently,there are many non-contact vision measurement methods for small workpieces with high accuracy.However,there are relatively few methods for large-size objects and large-field scenes,and the existing methods are not very accurate and complicated to calculate.Therefore,it is necessary to find a large field-of-view measurement method.Among the existing large field-of-view vision measurement methods,the line structured light sensor in multi-sensor has received more and more attention in the field of vision measurement for its advantages of wide range,high accuracy,good movability,and active control.Therefore,the application of multi-sensor is widely used in large field-ofview measurement,but its calibration and measurement are limited when two cameras in multi-sensor are in non-overlapping field-of-view.The accuracy of vision measurement depends largely on the calibration results and precision,so the study of calibration methods for binocular measurement systems in non-overlapping fields of view is a key step in vision measurement.At present,there are many calibration methods for multi-sensors with non-overlapping fields of view,but they all have certain limitations,usually require expensive auxiliary equipment,complex operation and low robustness.Aiming at the shortcomings of these existing methods,this paper proposes a calibration method for binocular measurement system suitable for non-overlapping fields of view.Specifically,it is proposed to use the imaging characteristics of the plane mirror to convert the cameras with non-overlapping fields of view into overlapping fields of view,and gradually deduce the conversion relationship between the two cameras with non-overlapping fields of view,thus solving the problem that cameras with non-overlapping fields of view cannot be observed.For the problem of the same target,the unified calibration of cameras with non-overlapping fields of view is completed.For the field-of-view characteristics of non-overlapping field-of-view binocular cameras,the current line structured light measurement methods are studied in this paper.Considering some practical problems in the non-overlapping field of view measurement of the current linear structured light sensor measurement system,a simple stereo target is designed to realize the linear structured light plane calibration of the non-overlapping field of view.The designed stereo target is different from the traditional stereo target.Targets are relatively simple to make.A linear structured light vision system with non-overlapping fields of view based on a stereo target is built.Only one laser and two cameras can form two sets of linear structured light sensors.Compared with the traditional method,the manual error of adjusting the light plane is reduced.To a certain extent,the calibration accuracy of the linear structured light plane is improved,and the experimental cost is low.Experiments show that the method proposed in this paper is effective and can accurately calibrate cameras and line structured light planes with non-overlapping fields of view.The method is simple and general,and is suitable for environmental measurements with large fields of view.