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In order to improve the traction performance of a wheel of a micro-tiller on the soil surface of a paddy field, we extracted the surface curve of a cow’s hoof and used the cow’s hoof as a bionic prototype to design a bionic paddy wheel. In order to verify the passability of the bionic paddy wheel in paddy soil, a wheel-soil test bench was built in the experimental field with a moisture content of 36%. The test results show that under the condition of the same load on the wheel, the changing laws of torque, drawbar pull, and slip ratio of the bionic paddy wheel and the conventional vaned wheel are similar. The torque and drawbar pull of the bionic paddy wheel are higher than those of the conventional vaned wheel at the same slip ratio. The maximum torque and hook traction provided by the bionic paddy wheel and the conventional vaned wheel both increase with the increase of the load on the wheel. Under the same load on the wheel, the bionic paddy wheel is at least 22% higher than the conventional vaned wheel. Compared with the conventional vaned wheel, the bionic paddy wheel can provide a higher driving force and hook traction, which can improve the working efficiency of the vehicle in the paddy field.

Abstract-To study the application of wireless sensor in the ship dynamic positioning system, the distributed fusion function model and structure model of wireless sensor network were set up. Using the DJC model-based SVM prediction algorithm, the quadratic optimal performance index in ship dynamic positioning MPC control was solved and the optimal control thrust was obtained. According to the classic cluster routing protocol, a data fusion structure based on residual energy and dormancy scheduling mechanism was proposed. The results showed that the proposed routing protocol based on the residual energy and sleep scheduling mechanism data fusion structure was superior to the Leach protocol. It improved the real-time performance of data transmission. Thus, the network data fusion structure achieves the goal of energy balance. The energy consumption is reduced to a certain extent and the design is reasonable.Keywords-wireless sensor, ship navigation, model, system IntroductionThe wireless sensor network is used in the ship positioning system. Ship position information, heading information and environmental information are monitored. The system requires each sensor node to transfer the measured information to the control system, so that the controller can calculate, analyze and process information. Here, the controller is not realized by the traditional computer, but by the convergence node of the wireless sensor network. It has good flexibility and reliability. In the ship positioning control system, the control object mainly includes three aspects: position control, heading control and track control. Combined with data fusion model of ship dynamic positioning system, the application of decision control method based on sink node fusion structure in optimal control thrust prediction is studied. Based on the cluster data fusion structure, the network transmission protocol of the ship dynamic positioning system is designed. 98

In order to improve the traction performance of the micro-tiller wheel on the paddy soil surface, a bionic paddy wheel was designed with a cattle hoof as the bionic prototype, and its diameter and wheel width were 0.46 m and 0.08 m, respectively. The traction performance test was carried out in a soil bin test-bed with a moisture content of 36 %. The vertical loads were 82.57 N, 131.40 N and 179.42 N, respectively. The driving speeds were 0.3 m/s, 0.5 m/s and 0.7 m/s, respectively. The drawbar pull was in the range of 10 – 120 N. The results showed that at the driving speed of 0.7 m/s, with the increase of the vertical load, the driving torque and the drawbar pull are increasing. The vertical load has a significant effect on the change of driving torque and maximum drawbar pull. Under the vertical load of 179.42 N and different driving speeds, when the slip ratio is less than 0.37, the efficiency coefficient begins to grow rapidly, and the greater the driving speed is, the greater the growth rate is. When the slip ratio is about 0.37, the efficiency coefficient reaches the maximum and then begins to decrease. Driving speed has a significant effect on the maximum efficiency coefficient of wheels. This paper can provide a reference for the traction performance of the micro-tiller wheel on the paddy soil surface and the design of the new bionic paddy wheel.