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OBD (On-Board Diagnostic) test system is applied to research influences of environmental parameters (altitude and environment temperature) on real-world NOx emission and fuel consumption for heavy-duty diesel trucks in this paper. The research results indicate that altitude and environment temperature have great influence on NOx emission rate and fuel consumption. High altitude in range of 3000~4000 m results in NOx emission rate is lower than low and moderate temperature because of air intake amount decreasing. However the fuel consumption rate is higher than lower altitude because altitude influences real-time changes of air inflow and combustion conditions in the cylinder of the engine. NOx emission rate and fuel consumption is more stable at different vehicle speed, VSP and RPM at high altitude, and NOx emission rate fluctuate dramatically at low and moderate altitude. The fuel consumption rate is higher at 10~20 °C than that at lower and higher temperature.

In this paper, it was researched the degradation characteristics of catalytic performance of three kinds of DPFs (C1, C2 and C3, with precious metal concentrations being 15, 25 and 35 g/ft3 respectively) after diesel truck aging. It is found out that the crystallinity of three kinds of DPF samples (Used) in full vehicle aging was higher than that of fresh samples (Fresh) and aged samples (Aged) in the laboratory. Compared with Fresh samples, the concentration of Pt atom in precious metal on the surface of Aged and Used samples tends to decrease in most cases. Activities to CO and C3H8 of Aged and Used samples of three kinds of DPFs had all been degraded, and activity degradation showed a substantial correlation with concentration reduction rate of precious metal on the carrier surface. NO2 productivity of Used samples all rose. Crystallinity of DPF samples after full vehicle aging in Inlet, Middle and Outlet areas successively increased.

In the paper, the research and design work of an automotive safety device is introduced. The device can automatically range, display the distance between the automobile and obstacle and sound alarm at a frequency varying with the distance. Equipped with the device, automobiles can avoid collision caused by drivers not noticing obstacles or not properly estimating the distance between automobile and obstacles when backing up. In the paper, the principle, the software, the hardware and the anti-interference technology of the device are concisely depicted. Test results showed that it is effective in collision avoidance.

The paper introduces an on-board fault diagnosis strategy based on analytical redundancy suit for automated mechanical transmission (AMT). Through experiment and theory analysis an identified engine model, a gear box model and a dry clutch model controlled by hydraulic actuators are respectively established. The information redundancy in the local models of the power train and the structure logic relations among the assemblages is used to detect and diagnose the fault in the sensors, the actuators and the unit assemblages of the AMT system. The method has been used in the AMT control system developed for the SVWSANTANA2000.