Sistema experto reparación mecanica

o World Academy of Science, Engineering and Technology 12 2005

An Expert System for Car Failure Diagnosis
Ahmad T. Al-Taani
knowledge base will contain the expertise of Ford's top diagnosticians, and it will make their diagnostic skills available to mechanics in every Ford dealership in North America. This system will guide a human technician through the entire service process, from theinitial customer interview at the service desk to the diagnosis and repair of the car in the garage [3]. There are a lot of related expert systems in the literature concerned with diagnostic problems. Daoliang et al. [4] presents a web-based expert system for fish disease diagnosis. The system is now is use by fish farmers in the North China region. Yu Qian et al. [5] proposed an expert system forrealtime failure diagnosis of complex chemical processes. Other diagnosis systems are described in [6-9]. A knowledge-based system for car failure diagnosis is presented in this paper. Section 2 gives a brief description of the problem domain. Section 3 presents the proposed system. In section 4, I will give some discussion and finally I will draw some conclusions. II. PROBLEM IDENTIFICATION Theproposed system divides car failures into three major types: 1. Start-up state, problems that may occur when a person try to start up the car, for example; engine does not work, some sounds noticed, engine works ones and stops. These problems could be due to one or more failures; will happen, the battery needs to be recharged, the dynamo is dead, or the battery is dead. 2. Run-stable state, problemsthat may occur after starting the car, for example; unburned fuel, cycle on-off, blue gas emitted, avance is very high. 3. Movement-state, problems that may occur while the car is moving; this state also includes problems related to the brake system. Most of movement problems that might occur appears on the car’s tableau the proposed system takes advantage of these facilities and use them todiagnose the problem and to gives advice of the solution to the driver. Some of these problems are: oil pressure, water temperature, voltage, and fuel pointer. If the car is in the start-up state and doesn't start, then the cause could be one of three main reasons: a bad fuel mix, lack of compression or lack of spark. In addition, thousands of minor things can create problems, but these are the mainthree. Bad fuel mix: A bad fuel mix can occur in several ways: 1. The car ran out of gas, so the engine is getting air but no fuel.

requires high level of expertise. Any attempt of developing an expert system dealing with car failure detection has to overcome various difficulties. This paper describes a proposed knowledge-based system for car failure detection. The paper explains the need for anexpert system and the some issues on developing knowledge-based systems, the car failure detection process and the difficulties involved in developing the system. The system structure and its components and their functions are described. The system has about 150 rules for different types of failures and causes. It can detect over 100 types of failures. The system has been tested and gave promisingresults.

Abstract—Car failure detection is a complicated process and

Keywords—Expert system, car failure diagnosis, knowledgebased system, CLIPS.

XPERT systems (ES) are a branch of artificial intelligence (AI), and were developed by the AI community in the mid-1960s. An expert system can be defined as "an intelligent computer program that uses knowledge and inference procedures to solveproblems that are difficult enough to require significant human expertise for their solutions [1]". We can infer from this definition that expertise can be transferred from a human to a computer and then stored in the computer in a suitable form that users can call upon the computer for specific advice as needed. Then the system can make inferences and arrive at a specific conclusion to give...