Research On The Welding Point Addressing Navigation System Of Ultrasonic Welding Robot

Thermoplastic is widely used in industrial production because of its advantages of rapid prototyping and repeated processing.Ultrasonic welding is of great significance in the field of thermoplastic assembly.In the traditional ultrasonic welding process,the operator usually judges the position of the welding hole visually,and manually guides the welding gun to move until the position information of all the welding holes is recorded,and then the welding path is programmed to complete the welding.This process is not only time-consuming and laborconsuming,but also its accuracy depends on the experience of the workers,and it is easy to make mistakes.Therefore,it is necessary to propose a method that can automatically complete the welding process The welding navigation system of art.As an important means of transportation in recent years,the demand for the use of automobile door panel is increasing,and its quality has more stringent requirements:(1)With the help of the design documents provided by the manufacturer,the manipulator is used to drive the camera for each welding hole.Through the contrast experiment,variance function is selected as the definition measurement index,and the definition is adjusted automatically until the welding hole image is clear enough.Then use Hough Circle transformation and minimum multiplication fitting to find the circle curve.Then we use control variable method to find the moving step length of the manipulator and critical threshold.Control the manipulator to move back and forth to complete the coordinate correction,so as to get the position information of each welding hole,and implemente a complete set of algorithms..(2)Due to the complicated procedures to obtain the design documents,and the requirement of positioning accuracy of ultrasonic welding head is not very high,the work site hopes to have a simple and fast method to obtain the solder joint coordinates,such as directly identifying and calculating the solder joint position after shooting the workpiece.This paper studies the welding navigation system based on binocular vision.Zhang Zhengyou's calibration method is applied to complete the calibration and system correction of left and right cameras.Four positioning circles with known position information are identified and located,and the projection matrix from camera coordinate system to world coordinate system is calculated.Through comparative experiments,the improved channel processing,preprocessing,Hough circle transformation and least square method are used to find out each welding hole circle curve in the image The transformation matrix and translation vector complete the transformation of each welding hole in pixel coordinate system,image coordinate system,camera coordinate system and world coordinate system,and determine the position information of each welding hole.The system effectively improves the shortcomings of the traditional Hough circle transformation method,such as missing and false detection of some welding holes.Finally,this paper also realizes the design of welding navigation system based on image processing and binocular vision,realizes the communication between upper computer and manipulator and user interface design,which has good practical value.