| Welding of new energy power lithium battery module is a key link in assembly process of new energy battery module.Welding quality will directly affect product quality.At present,the price of imported integrated vision laser welding system is very expensive.In order to better adapt to the production process of domestic manufacturers and reduce production costs,this paper takes a practical project as an example to develop a Laser Galvanometer precision welding control system for new energy power battery modules,and two key technologies of vision and vibration mirror scanning were studied.Firstly,according to the technological requirement of aluminum bar welding for lithium battery module with square hard shell,the control system design and the overall structure design are carried out in order to improve the welding accuracy and speed up the welding efficiency.The whole system integrates the main components including galvanometer,laser,vision sensor,robot and servo motor through programmable controller.The controller coordinates the work of each subsystem to meet the needs of actual working rhythm.In order to ensure the influence of many deviation sources on welding accuracy,the system integrates visual subsystem to correct deviation.At the same time,in order to ensure the welding speed of the system,the galvanometer system is used to scan the laser welding path rapidly.For the control strategy,the control flow is about "the visual system work first later the galvanometer move",and the working mode is about "positioning before welding".Secondly,the Location Method of Machine vision system is studied,and the method of correcting the deviation of module laser welding is found on the basis of this theory.According to the actual situation,the light source and illumination scheme are selected to optimize the quality of the original image.Through the edge extraction algorithm,the least square method is used to fit the target curve to realize the localization of the welding model area.The scanning principle of galvanometer system is studied,and the corresponding relationship between galvanometer and visual system is found by the calibration method of "the position relationship between paraxial vision system and Laser Galvanometer processing system".Finally,the influence of welding parameters on the welding effect is analyzed.The welding effect of the system is verified by the results of welding products,slice test and tension test,and the high quality of the system is achieved. |
