Diesel Engine Online Monitoring Based on Smart Order Tracking Sensor System

A design of smart sensor system based on digital signal processor, acceleration sensor, magnetoelectricity speed sensor, Acoustic press sensor, gripper piezo-electricity sensor, A/D converter and CAN bus was introduced to establish a embeded system which can monitor the vehicle´s online working condition. The software and hardware of the system was introduced. The order spectrum of the acoustic signal and the speed curve under three different working condition was analysed. The result proved the theory that the order spectrum of exhaust acoustic signal is different under different working condition. Through writing order tracking and fault diagnosis programme in the DSP, the original signal was constant angle resampled, the fault diagnose parameter was get from the order domain of the acoustic signal, the angle domain of the cylinder head vibration or oil press signal. Use these parameter, misfire and other fault in diesel engine can be diagnosed. Compared with traditional methods, this smart sensor system didn´t need the diesel to run in a certain speed, it can diagnose fault when the diesel speed-up or speed-down, so it can monitoring the vehicle online.