A Assembly System Of Storage Battery Seal Based On Machine Vision Technology

As an isolation unit between storage battery with the outside world,sealing ring is used to prevent battery leaking that avoids risk happens.So the assembly process is very important.At present,many small and medium-sized storage battery manufacturers still remain in the manual operation stage of low production efficiency,high turnover rate and large labor intensity.Even though some enterprises have gradually introduced industrial robots in order to improve productivity and efficiency,most of these industrial robots use pre-teach or off-line programming to control the robot to complete the established command action.Therefore,the flexibility and adaptability of the robot are restricted to a great extent.Aiming at this problem,this paper designs a assembly system of storage battery seal based on machine vision technology,combined with the assembly process of the storage battery production process of the seal ring.First of all,according to the system requirements,the hardware platform of the system is designed and completed,including the selection of light source,camera,lens and core processor,and industrial robot and end effector of imaging system.Then,this paper discusses the visual positioning technology of the seal assembly,including the calibration of the visual system and the identification and location of the sealing ring and the sealing mouth.The vision system calibration acquires the internal and external parameters of the camera via Zhang Zhengyou's calibration method,calibrated robot's hand-eye,established the coordinate mapping relation of the spatial objects from the image space to the robot space.Based on this,as for the sealing ring,this paper discussed Hough circle detection and location by the use of the light reflection difference between front and back sealing rings;for the sealing mouth on the storage battery cover,discussed a contour extraction and circle fitting recognition algorithm.Also completes the dynamic tracking of the target sealing mouth combining with visual feedback and robot motion control.Finally,the system software is implemented and the system communication protocol is set up.The visual guidance unit software is designed in VS2012 environment combined with OpenCV.The implementation of the grasping algorithm,the placement algorithm and the tracking algorithm is completed.The robot control unit software is designed by PAC programming language.System test and analysis shows that the one-time assembly success rate of the system is more than 94%.After introducing the replenish assembly mechanism,the assembly success rate of the system is more than 98%.The average time to complete the assembly of 6 sealing rings of a storage battery cover is 11.62 s,which can fully meet the requirements of current assembly line production mode.