Study On Key Techniques Of Integrated Controller In Laser On-line Measuring System

A design of an integrated controller for laser on-line measuring system based on STM32F407 processor with high performance is reported,and it aims at solving the problem of too many control modules and complex wiring in the control cabinet of Car Body-in-white laser on-line measuring system installed in car assembly plants,as well as short circuit caused by fracture of flexible visual sensor cables at high strength work.The controller communicates with the host computer via Ethernet,and connects with vision sensors through RS-485 serial bus,controlling them to measure the white body of cars quickly and reliably.At the same time,voltage sampling way of short circuit protection is adopted in the power outputs,and deals with voltage sampling values in combination with the improved amplitude-limiting and limiter average filtering algorithm.Application in Beijing changan automobile welding workshop nearly a year shows that the controller is able to perfectly finish the control task in Car Body-in-white laser on-line measuring system.Compared with the original control system,the controller has the advantages of simple structure,running stability,low cost and fine real time.The main work of this paper is as follows:1.According to the design requirements of the integrated controller,select hardware platform,software platform and data filtering algorithm respectively.Complete the design of the integrated controller in the Car Body-in-white laser on-line measuring system.2.Analyse the hardware design of the integrated controller in detail.Design circuit principle diagrams of power supply system,CPU minimum system,Ethernet communication module,RS-232 and RS-485 communication module,memory module and control measurement module.Indicate the PCB design essentials of the integrated controller.3.Set up software platform of the integrated controller system.Design embedded system software of the integrated controller.Make the controller to realize the normal communication.In order to guarantee the reliability of communication,analyze the data conversion mechanism and its reliability.At the same time,on the basis of the existing data mining algorithms,combined with the system characteristics,design an improved amplitude-limiting and limiter average filtering algorithm.And it is able to quickly and accurately detect the system short circuit fault.4.Set up the experimental platform for the test of various functions in the controller.The results show that the controller can guarantee the measurement system operating safely and reliably.