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The thermal and mechanical loads of the engine rise dramatically with the increase in engine power density, which places higher demands on the design of the piston. In this paper, the design development of a steel piston for a marine diesel engine belonging to 190 series heavy-duty diesel engines was studied. The design methods including material selection and structural design were used to finished the preliminary design. In the meanwhile, the design philosophies of the aluminum alloy piston and composite piston for the 190 series diesel engines were used for reference in the design process. The designed steel piston was tested in the engine durability bench test and simulated for reliability. The results showed that the failure of the steel piston occurred at the same position in both the test and the simulation. The cause of cracking in the steel piston was analyzed, and the insufficient strength of the local structure led to high-cycle fatigue failure.

Although the video-based vehicle detection technology has the merit of low-cost, there are two obvious shortages: one is that the recognition effect is greatly affected by the weather and ambient lighting, and the other is that the amount of video data is large that may lead to the extra processing time. Compared with video-based and lidar-based technologies, millimeter-wave radar has some unique advantages in vehicle detection:(1) Sending and receiving signals are not affected by weather and illumination, and can perform all-weather measurements; (2) The cost is much lower than lidar, that is suitable for popularization; (3) The data processing and power consumption are superior to the vehicle detection system based on video processing. Therefore, this paper chooses FMCW-based millimeter-wave radar to build a vehicle detection system at an intersection.

Experimental results on an automatic lane keeping control study are presented in this paper. A magnetic reference system was used to provide the vehicle lateral tracking error as well as future road curvature information and vehicle speed measurement to the vehicle steering controller. The front wheels of the vehicle are steered according to vehicle lateral displacement, future road curvature, vehicle yaw rate and lateral acceleration, and vehicle speed. The control algorithm used to design the feedback and feedforward controllers is known as the Frequency-Shaped-Linear-Quadratic Preview (FSLQ-preview) optimal control design method. The closed loop response of the vehicle was examined under a wide variety of test conditions, including low tire pressure, measurement noise, perturbed reference system, hard braking, and snowy road.