| The resistance spot welding is used for the manufacture of aerospace and vehicle, because it doesn't need packing material, its high productivity, it's easily implemented automation and so on. However, it is the course of a high nonlinear, holding multivariable coupling and lots of uncertainty factor. It forms nugget vary fast. The nugget is a closed state and can't be directly observe. And To distill characteristic signal is very difficult. It brings some difficulties to quality monitoring. The international experts are making great efforts and they have got some success. But the quality fluctuation of nuggets and the problem of splash have not been solved.The recent years, my teacher has developed a new controller for spot welding whose control cell is embedded microprocessor system. The control strategy of the multiple messages is adopted by combining the constant current control technology with the dynamic resistance control technology. This control strategy is named as IDRC method. But it brings a new problem. Its control parameters is too many to memorize and hold, which is more than sixty, so modifying the parameters is quite difficult. If you want to program the parameters, you must hold the control algorithm and programming mind. The most important is adjustment strategy. It is quite difficult to workers. If the product line of automobile which has hundreds of pensile spot welding machine doesn't adopt the uniform management method, the quality of the nugget can't be ensured. So, to prevent the disturbance of technology quality, the programming must be uniformly managed.Moreover, it is helpful to increase the reliability of the quality management of the product to track the welding situation of every welding machine and store the technological parameter.To solve the problems, it is necessary to use the computer to uniformly manage several welding machines. It ensures the reasonability of making current of every welding machine and the safety of local electric network. The application ofexpert system is further increase the rigor and identity of programming the control parameters. The real time data and welding situation of every welding machine can be gathered and observed by the powerful ability of dealing with data and friendly interface of personal computer.Anyhow, the group control management software that is developed in the base of IDRC method, Visual Basic, Database and expert system is suitable for monitoring and management of the spot welding quality. And it is very significant for extending IDRC method to real productive field.The group control management system of spot welding can manage several welding machines all the same time. The management is implemented by communicating between computer and controllers of welding machines, but this paper only research the management software. The function of management software is to program the controlling parameter, inquiry the welded data, display the dynamic data curve and optimize the controlling parameter.Automatically programming system is designed for the characteristic that the controlling parameters of IDRC method is too many and the programming of IDRC method is too difficulty. Its basal conception is that different welding material, thickness of material panel and quality level needs different controlling method. When a group code of welding material, thickness of material panel and quality level is inputted in the textbox and"enter"key is clicked, automatically programming system can find and extract the corresponding controlling parameter. The course is implemented by specifically reasoning mechanism in the base of knowledge base forward chained reasoning rule.The function of inquiring data system is to inquiry the data that is stored at real time. The manager could analyze and evaluate the situation of welding through the data. The inquiring method is according to ID or date. When the manager clicks"enter"key, the system can extract the corresponding dynamic data.Displaying the dynamic data curve system mainly display the angle of lag curve, the dynamic curve and the dynamic heat curve whose data is carried to computer from the welding machine at real time, so that the manager can know thewelding course. When the curve is abnormal, the manager can know that the controlling parameter is unreasonable or the welding machine is abnormal.The operation of the resistance spot welding is simple, but the course of the spot welding is quite complicated. A lot of disturbing factor appears in the course of producing. So, the quality of welding spot often fluctuates, and the range of fluctuating is very large. Although the welding is according to the correlative control parameter, the welding course could come into being splash and nugget. To solve the problem, we should adopt effective monitoring method, at the same time, we should design the concourse of the control parameters to ensure the heat course to implement anticipative rule. The paper designs the optimizing system for control parameters of IDRC method. It can optimize the control parameters by using expert system according to the result of the characteristic parameters and man-machine dialogue. Then the manager sends the optimized parameters to the controller of welding machine.After operating and debugging again and again, the management software of the resistance spot welding group expert system has possessed those functions. The software has a benefit man-machine interface, and it can be operated simply. And the problem of operating difficulty has been solved. So it makes the IDRC intelligent control technology more significant.
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