Research On Binocular Vision Welding Robots Control Key Technologies Based On Three-Dimensional Surface

The welding robot research on soldering industrial any space surface’s weld is a hot issue, it is the key to achieve soldering process automation, intelligence and information. Because of the problems such as weld model difficult to determine, welding robot’s weak autonomy, welding efficiency too low, large disturbance on soldering process, a binocular vision welding robot system contrary to space surface weld is constructed. This thesis uses methods such as Stereo-Matching, Weld-modeling, Locus-Tracking, Route-Planning to optimize the above problems.This thesis mainly does the following several aspects of research work:1. A binocular camera calibration algorithm based on a two-dimensional calibration template is researched. On the basis of convert matrix from two-dimensional calibration template to camera imaging plat and the relative position of the camera, internal and external camera parameters are calculate, By nonlinear optimization algorithm the noise and distortion effects of the camera is reduced, the accuracy of camera parameters is improved.2. A multi-information matching method based on adaptive windows is proposed. The edge feature point abstract algorithm based on canny operator is improved for stereo matching problem of weld in welding image, the set of candidate matching points are reduced according to similar constraint of edge difference strength, gradient direction and polar constraint, the neighborhood information of matching points are used to build adaptive support windows and start to dynamic growth, the only correct matching point is fixed by cost function of windows, the experiment shows that the preciseness can improve edge detection accuracy and inhibit noise by using the algorithm.3. A locus-tracking method based on fitting space weld is proposed. For the problem of what dispersed edge weld spot can’t be directly used by welding robot system, the edge points in the same direction is divided into several intervals according to number threshold, using the least squares linear to fit each section of the weld points, achieving the online tracking to weld orbit by shooting the real-time weld image and correcting the position.4. The robot path planning algorithm on three-dimensional joint space is researched.Considering the traditional cubic polynomial path interpolation algorithm for robot path planning problem, interpolate to path point in the case of the past path point does not remain bounded, using combined two cubic polynomial to plan path, increase the buffer area of the parabola in the neighborhood of waypoints, So that the displacement of the joint, the speed transform a smooth continuous function, the effect what the linear interpolation algorithm has a shock to goal workpiece is improved.This thesis uses Matlab-software to do the camera calibration and stereo matching experiment, the result shows that this thesis’s algorithm is feasible.