The Research On Computer Monitoring And Fault Diagnosis System Of The Hydraulic Controlling System's Running State

When the hydraulic system is out of order, according to the comprehensive, complicated and difficult problem, the paper developed a hydraulic system fault monitoring and diagnose expert system software platform making use of the expert system and the fuzzy math theory together to realize the hydraulic system monitoring online and diagnosis function offline, which can find the fault's position and reason quickly and also can offer the fault's exclusion measures, therefore, the system software can help the technician and operator avoid finding fault blindly. So it can save the time of examination and repairing when it is failure. At last, it implores the economic benefits and production efficiency.This system uses VB6.0 as the system development software. Firstly, it constructs a monitoring system about hydraulic system, that is the parameters as pressure, flow, temperature and so on, which import to computer software from sensors by data acquisition, analyze and dispose the data, extract signs of information and save them. According to the symptom of information to the normal scope of work, judge it is can appear fault, if it has no fault, the system can forecast its trend according to the changed parameters, if it has a fault, the system can alarm by the sound alarm and the warning lights. Secondly, the paper establishes hydraulic system fault diagnosis expert system platform, describes the foundation theory in detail about the knowledge base, real-time data base, knowledge express and the man-machine interface. This system establishes knowledge base and real-time database using ACCESS, uses production-rules representation to express domain expert's knowledge, uses data driver's positive reasoning mechanism, depth-first law's search strategy and imprecise reasoning's consequence to finish inference engine's design, uses the report forms, files, graphics integrated approach to accomplishing the man-machine interface which the computer and user can communicate conveniently. At last, using the fuzzy math theory, the paper shows the fuzzy comprehensive assessment results to user, orders fault's credibility according the reason of the fault, excludes and checks the fault it itemized.The paper implements hydraulic system failure monitor's visualization. On the presupposition of the knowledge and the evidence uncertainty, it used fuzzy fault diagnosis'method to finish the excluding of the hydraulic system's fault, and it has passed experimental test and has been proved to have effectiveness, feasibility and extent practicability.