Automatic transmission test data acquisition system development based on virtual instrument

An electronic automatic transmission test data acquisition system, which makes use of American NI's data acquisition card and CAN card, is designed based on Virtual Instrument. The data can be collected by the data acquisition system include automatic transmission oil pressure, solenoid duty ratio, as well as CAN message issued by automatic transmission and engine control unit. The key problems of the system design are measurement method of automatic transmission solenoid duty ratio, signal conditioning circuit design and multi-signal acquisition synchronization. Test platform is North-Benz dump truck 2627K (Its power-train assembly is replaced), of which transmission and engine use respectively HD4070PR electronic automatic transmission and BF6M1015CP electronic diesel engine. The automatic transmission shift control strategy and oil pressure characteristics of clutch or brake etc can be obtained through test data acquisition.