The Software Research And Design Of Calibrating Apparatus Closed-loop System Of Wave Buoys Based On MFC Multi-threading

The essay centers on the research work of Calibrating Apparatus for JBY1-1Wave Buoys upgrading project that needs to be solved. At the beginning of the article,the framework of the closed-loop control system is given, using asynchronous ACmotor and speed reducer as its power source, multiple sensor detection devices for itsfeedback units, industrial control computer for its controller, data acquisition cardsand the transducer as its actuator. The AC motor adopts frequency conversion control,with the control algorithm of digital incremental PID formula. In order to acquire theappropriate PID parameter, we do a large number of debugging experiments. Ofcourse, this needs practical experience to try and error.This paper aims to design a Graphical User Interface (GUI) based on Visual C++MFC framework, making it simple to program, easy to operate, powerful and easy toexpand, beautiful to look, interactive to work and so on.During the software design, multi-tasking data processing makes the single threadprocedure can·t satisfy the requirement of real time, especially in this issue, becausethe procedure must deal with circular process with a large amount of data from threesensors. In addition, it needs to synchronously update data in the correspondinginformation bar.What·s more, it also need to draw the ideal and actual operation sinecurves in real time on the interface. Consequently, the essay adopts multithreadingtechnology which Windows system support, it has a significant influence onimproving the program execution efficiency in time or space, making the procedure toexecute concurrently and overcoming the single thread execution problems. However,concurrent execution of multi-threading will inevitably compete for the same sharedresource, leading to some obscure bugs. So it requires thread synchronization betweenmulti-threads to ensure that a certain moment only one thread can access to the sharedresource, while other threads can·t access but only wait.In order to better coordinate multiple threads to complete the tasks, it is no doubtthat communications between multi-threads have a decisive role on enhancing systemperformance to the software. This paper describes three main kinds of threadcommunication methods: global variable communication, user defined messages and event objects, and also gives some chief code implementations.Then, this paper summarizes the main points and difficulties during the process ofsoftware design, and gives the correspondingly solutions and presents the GUIinterface of this application.At last, after whole verification device upgrading, we have done a lot of testingwork, the actual operating results show that: the hardware system with closed-loopcontrol is reasonable and software user interface is easy to use, interactive and fullyfunctional. Multi-threading technology realizes multi-channel signals to collect andprocess in real-time. Overall coordination achieves a very high precision, meets theocean wave buoy verification method and realizes a further upgrade.