Applied Mechanics and Materials Vols. 494-495

Abstract: At present, the detection accuracy of monitoring method by human ears is not satisfying in the pure tone detection of on-vehicle loudspeakers. To solve this problem, a new method is proposed to convert vehicle loudspeakers response signals into a two-dimensional image signal via wavelet packet analysis, which can increase the time-frequency of malfunction information. Through image binaryzation and pretreatment image-edge detection, the resulting signal would be recognized with box-counting dimension acquired in the process of gaining time-frequency image through fractal dimension as malfunctioned indications. Experiments show a rate of fault recognition as high as 95% , which meet the requirements of online vehicle loudspeaker detection.

Abstract: Hydraulic modulator regulates the pressure of four wheels independently to realize the Anti-lock Braking System (ABS) and the Electronic Stability Control (ESC) function. The pressure regulator, also called hydraulic control unit, works by controlling several valves to realize the on-off operation of the liquid paths. This paper focuses on working mechanism and hydraulic response characteristics of inlet valve of hydraulic control unit through simulation analysis.

Abstract: Firstly mechanical model of hydraulic powerplant is established. Then mathematical model of hydraulic powerplant mount is established based on the analysis of mechanical model. And the simulation model is established in Matlab/Simulink. The results of simulation are attained by calculation. On the basis of aforementioned results, the analysis is made. Finally, this paper makes a summary and outlook.

Abstract: To complete experimental platform for electronic fuel injection simulation, an electronic control system has been built. The system, which can control the fuel injection of engine precisely, connects the sensors, ECU, and the actuator device with buses. After testing the electronic fuel injection simulation experimental platform, we make the MAP with the data of experiment. The data is reliable, which can prove correctness of the control system, and the system can control the engines fuel injection.

Abstract: This paper conducted a research to analyze the chassis of the tractor by finite element method. The four working condition of the chassis was analyzed in ANSYS and finally the stress and displacement nephogram was obtained. The research provided a way to improve the performance of the tractor chassis.

Abstract: In this paper, safety evaluation index system was made up on the automotive industry, and we make evaluation of 2001-2011 automotive industry safety by the method of gray model, The research indicates that China automotive industry has been in a basic safe condition, which shows it is in a positive trend. Nevertheless, the range of the development of industry by which the competitiveness index measured was too large, which means the development of automotive industry was to a much extent affected by related policies developed by government, the market is not rational. The researchers also indicate the major reason of the Less competitive of Chinese automotive industry and over-rely on the export, which is low R&D investment and lack of key production technology. The conclusion of this article plays a role of guidance for government to promote effective automotive industry development policy.

Abstract: The hot-film flow sensors accurately measure the intake flow of engine. The air flow in the engine intake manifold is typical unsteady flow whose flow velocity changes remarkably. Therefore, the flow sensor should have a faster dynamic response characteristic. A thermosetting coupling model of a hot-film sensor was established based on CFD which is used to simulate dynamic response characteristics; the temperature field of the hot-film flow sensor probe was simulated. In addition, the dynamic response characteristics of the sensor simulated using the step pulse, and tested the dynamic response characteristics based on flow test equipment.

Abstract: Using GT-POWER to simulate a diesel engines injection timing, calibrating simulation model has been done according to experimental data. Analysis of the effect on engine power characteristics and emission characteristics caused by different pre-injection timing and main injection timing is the main work. The simulation results show that, the output torque and NOx increased when the injection timing is advanced. In contrast, the soot emission is decreased when the injection timing is advanced.

Abstract: There are considerable difference between the actual distance and that measured by infrared or ultrasonic ranging. The car reversing isnt intelligent enough. In order to solve the issues, this paper design an automatic car reversing auxiliary systems based on monocular sight. The system hardware mainly consists of image collection module, embedded micro-controller, and electronic braking module. On the basis of the distance measurement algorithm based on monocular sight, the real-time distance to the front vehicle can be measured and can be auxiliary controlled via the data exchange among vehicle electrical control units. The vehicle dynamic driving experiment verifies the high reliability of the vehicle automatic reversing auxiliary system based on monocular sight. The distance measurement errors are less than 2% when the distance to the front barriers is in the range of 20m~70m. The system can satisfy the real-time requirements for the vehicle intelligent auxiliary braking.

Abstract: For the problem of the vehicle parts monitoring in the internet of vehicle, the service technology is proposed to access the detail components through the common gateway interface technology. The information transmission is managed using the common gateway interface and interface parts for docking, and the monitoring of detail parts is made by the bus integration monitoring. IPv6 virtual network address information transmission is used to avoid the hidden dangers of IPv4 address depletion, and the virtual and independent IPv6 address is transferred with the part number in the common gateway interface to achieve a wide geographical access. In order to achieve real-time information exchange and robustness, the real-time transport protocol and real-time transport control protocol is used to assure smaller transmission delay and less packet loss rate. The test results show that the average response time is no more than 85 nanoseconds and the accuracy of information transfer is not less than 98.2%, and the results meets the needs of the most environmental, and the program is viable in practice.