| The bumper is an important safety component in car, so various of mechanicalproperties requirements of the bumper tend to be higher, but the fact is on the contrary. Thealuminum bumper which is usually used in the car do not meet the relevant requirements inmost indicators of intensity, so Heat-treatment technology is usually used to improve thevarious mechanical properties of bumper. At present, there is still a certain gap in thecontrol level of heat-treatment technology in our country when compared with abroad.Most enterprises still use the control method of traditional PID to regulate the temperatureof the heat-treatment furnace. For the heat-treatment furnace with the features ofnonlinearity, pure time delay and great inertia, this traditional control method of PID has alow control quality, the stability and accuracy are both not very well, and it is easy toappear relatively substantially fluctuations, all of these disadvantages finally would cause adefect. Therefore, in order to improve this situation, improve the quality of heat-treatmentcontrol technology in our country, and promote our country’s industrial production ability,the research of the heat-treatment furnace temperature control technology is particularlyimportant in the present.Firstly, this paper collected a lot of literatures about the heat-treatment controltechnology at home and abroad, after the in-depth research on these literatures, this paperfinds out the important factors that restrict the development of heat-treatment technology inChina, such as the equipments’ advancement and reliability, the rationality of the process,and the advanced control strategy, etc., the most significant factor is the control strategies.Therefore, this paper tries to integrate the advantage of traditional control methods withforeign advanced control methods as a whole, achieve the complementary advantages, andputs forward a control method named fuzzy PID based on mutative field as theheat-treatment furnace temperature’s control strategy.Secondly, in order to verify the feasibility of this method, this paper selected abox-type heat-treatment resistance furnace as the controlled object, completed theestablishment of its mathematical model, and using the MATLAB\SIMULINK platform,four types of simulation model is established, they are traditional PID control, the fuzzycontrol, fuzzy PID and the fuzzy PID based on mutative field. Through the simulationexperiments, this paper proved the advantages of fuzzy PID based on mutative field controlstrategy and the feasibility of its used in the control system of heat-treatment furnacetemperature. And then, this paper began to design the hardware platform for the control system ofthe heat-treatment furnace temperature. Lower level computer uses a high cost-effectiveAT89S52singlechip as the CPU, K type thermocouple as the sensor and MAX6675chip asthe thermocouple’s A/D converter. When the singlechip gets the input command, thecontrol quantity can be calculated according to the control algorithm adopted in this paper,and then through the photoelectric coupler and two-way thyristor driven actuators, thecontrol of the heat-treatment furnace can be completed. Upper computer uses theLABVIEW development software to realize data processing and monitoring of thetemperature’s display.In the last part of the paper has carried on the debugging process and commissioningto the control system which has been researched and developed, the experiment resultsshow that the stability and the control ability of the furnace temperature control are bothreliable, control accuracy is high, too. In addition, author also makes use of the controlsystem that has been developed to research the technology of heating processing for thebumper that in this paper needs to be heat-treatment. After a lot of exploring experimentand product mechanical properties test, the author determines the heat-treatment processparameters that could satisfy the requirement of designing aluminum bumper. |
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