Virtual Instrument Technology Is Applied Research In The Gasoline Engine Performance Testing System

In recent years, because of the use of electronic controlled fuel injection engine, it is certain that a engine general performance detect instrument will be used widely by a car maintenance company. But, several kinds of domestic engine performance measuring instruments still exist some problems, and the price of abroad instruments all of which use English as a communicating tool is high. So, the instrument hasn't been used widely now. The occurrence of virtual instrument which is a kind of new instruments concept bring a new resolution for this problem.The detecting system developed using computer as a controlled unit and virtual instrument software platform Lab VIEW will show enough the merit of virtual instrument technology, and have following features: friendly interacting interface, agility and convenience, good performance, low cost and high efficiency, and the shorten developing period.This dissertation introduces the technology when designing the detecting system of gasoline engine general performance. This system includes following sections:1. the starting performance detecting module. It can detect a voltage of an accumulator, a starting/charge current, a cylinder pressure and a starting rotational speed. A user can judge the quality of this accumulator.2. the ignition performance detecting module. The instrument can detect a ignition advanced angle, a closed angle, a overlapped angle and a engine rotational speed, and also can display a ignition wave.3. the dynamic performance detecting module. This system can detect a engine accelerated speed and average power, and display the engine speed characteristic curve during detect.4. the valve timing detecting module. The instrument can calculate and display a valve timing.5. the strange noise caused by vibration detecting module. The system can save and redisplay various engine strange noise wave, which can provide analysis basis for failure diagnosis, and users can judge some failure by compare these waves with normal wave.In this system, we realize the detect of all of single module using the main program, the detect results can be shown in a front panel as several kinds of style. At the same time, the system can restore and print datas.The experiment prove that the developed detecting system have stable performance, high accuracy and friendly interface, and it can be operated easily. All of this show enough those merits of virtual instrument.