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The wheat precision seeding technology provided an advanced agricultural protection for the high yield of wheat. But the lack of an effective agricultural machine made this technology difficult to apply widely. In this paper a quadruped wheel robot to achieve the wheat precision seeding technology was designed. And experimental study was taken under different operating conditions. Because of multiple effort factors, a quadratic orthogonal rotation combination design method was applied in the experiments, and identifying the main factors by analysis. Then the field test was carried out according to the main factors. The experiment results showed that the qualified rates of seeding exceed 93% in different sowing speed. That reached the agronomic requirements of wheat precision seeding.

Turbulent fluidization is a flow regime between bubbling fluidization and fast fluidization. The influence of static bed heights and axial locations on transition velocity was studied from bubbling fluidization to turbulent fluidization in a 368 mm×368 mm square fluidized bed, based on the pressure gradient fluctuation by measurement differential pressures transducer of FCC. Experiment results show that the transition velocities increase with decreasing location of observation or increasing static bed heights. And the transition of regime from bubbling fluidization to turbulent fluidization is a process gradually happened from the upper to the lower bed section and is not instantaneous behavior in the whole bed. Based on those, the prediction model is built that the average solids concentrations of bed cross-section are used to reflect the variation of gas-solid interaction along the bed height. The new prediction correlation by fitting parameters of experimental data is in well agreement with experiment results

This paper presents a novel method to control a robot arm based on the human skeletal information. First, the depth data is obtained by using a Kinect device. Skeletal tracking technology is used to deal with the depth data to match the various parts of the body and the 3D coordinates of each joint of the body are established. Then, the 3D coordinates are proposed to calculate the rotation angle of the human waist, shoulder, elbow and wrist joints. These four joints of the body are one-to-one correspondence with the four joints of 4-DOF robot arm. Finally, a transformation is conducted to map the calculation results into control commands, and the control commands are sent to the controller of robot arm by serial ports to achieve body feeling interaction. The experimental results show that the method can effectively control the robot arm to rotate and grab objects.

The processing of three-dimensional structure and servo feed systems for micro-EDM have strict requirements.The two positioning method is used to solve the contradiction between the large stroke and high precision, Coarse and fine action units matched to achieve the precision positioning requirements. A combined device with piezoelectric ceramic and step motor has been employed as drive and use the linear rolling guide As the transmission in this study,which has strong control function ，great flexibility, high positioning accuracy and repeatability. The basic performance of the platform met the needs of micro-EDM control.

The electrochemical degradation of nitrobenzene in undivided and divided cell using Ti/SnO2-Sb2O5 anode was studied. The electrochemical degradation of nitrobenzene is of the results together by anode and cathode. Two general possible paths of the electrochemical degradation of nitrobenzene are proposed: (1) Nitrobenzene was first oxidized to p-nitrophenol. Then p-nitrophenol was degraded to hydroquinone, benzoquinone, maleic acid and oxalic acid, etc. Finally, all of the intermediates were oxidized into CO2 and H2O. (2) Nitrobenzene was mainly reduced to aniline at the cathode，aniline was degraded to 4-aminopheol, hydroquinone, benzoquinone and other intermediates at the anode, then all of the intermediates are oxidized till complete degraded and mineralized at last.

Because of the separation of modified truck’s cab and car tank, there must set long wires to transmit the signal. A liquid level measuring device for truck is designed and developed in this article. Using the ZigBee technology, a wireless data transmit mode, including the hardware and the software, is realized. A compensation and correction method is discussed on the basis of the ultrasonic transmission theory. This device has a simple structure, high precision, low cost, easy to install and so on.

The wheat precise seeding technology is an effective way to increase the production of wheat. Walking precision of the agricultural machinery combined with precise seeders has a directly effect on the accuracy of sowing. The real-time tracking technology has become the main problem in agricultural fields. In this paper, the kinematics model of a mobile robot was established and MATLAB was used to make simulation analysis of Path tracking. The results meet the requirements of the robot path tracking and provide technical support for precision seeding.

Designing a high quality and low cost servo control system of micro-EDM is the key technique of high precision micro-EDM. The paper solves this problem by designing an embedded servo control system of micro-EDM. The servo system realized the FOC of PMSM by using embedded technique, which connect the servo controller and the pulse generator properly. The scheme of servo control system has the merits that it is low cost, flexible and self adjustment of discharging gap.

Wheat precision seeding test system is designed to develop a measurement device of wheat precision seeding with high efficiency and precision. The wheat seeds are falling from the seed sowing device to the conveyer belt. Using image processing techniques, the system gets the pictures of seeds on the belt. Then these pictures are processed and analyzed to calculate the qualified rate, reseeding rate and leakage sowing rate, etc. This paper introduces the whole structure, design parameters of the system, the hardware and software of the image acquisition system. Through selection of a proper threshold, the method of seed identification and seed-space measurement are given in this paper.

The research for the innovative training model is meaningful, because it is the key of vocational college service for regional economic development, foster high-quality practical and technical talents. The research for the cooperation of college and factory can create sustainable training development environment, and increasing the effectiveness of training. At the same time, the constructive proposal of teacher groups' mutual recruitment and communication can solve the contradiction of training organization’s structure. In the end, the research has highly feasibility due to it focuses on profits, responsibility, and management mechanism between colleges and enterprises.

In ultra-precision cutting, grinding and special processing, it is difficult to resolve the conflict between the large stroke and high-precision feed, which is also a headache for multi-axis ultra-precision machining. In order to construct a low-speed micro-electron discharge machining system adaptable to a wide range of micro-methods and driven by ultrasonic motors (USM), the program attempts to design the base platform for precision Motion Platform. By analyzing the dynamic and the static properties for the platform with ANSYS software and comparing the designs of platforms, the design of the base motion platform has been completed. After testing the performance of the platform, the design has met the requirements. The research can be treated as a universal solution in the design of the base platform for high-precise motion areas.

On ultra precision cutting, grinding and non-traditional machining, there is a hard problem between long travel and high precision. A new multi-dimension, low speed, nanometer level precision minute electric spark forming system driven by ultrasonic motors was built. A study of the basic characteristics of the ultra-precision platform driven by the ultrasonic motor was conducted in this paper. The control method of digital PID combined with bidirectional static error compensation enables the platform to realize the submicron accuracy in a stroke of hundreds of millimeters, with the minimum speed of 0.1μm/s and the minimum closed loop step of 100nm. All the achievements would provide theoretic reference to the design of these kinds of ultra precision platform.

A host computer packaging cushion is designed, including deflection, buffering capacity, creep checking. Then g a three-dimensional model of the host buffer packaging systems is established Simulation of the system, including static analysis, modal analysis, harmonic analysis and transient dynamic analysis. Finally, the physical system is used to do the sine frequency, fixed-frequency sinusoidal vibration test. the vulnerability of the buffer package sinusoidal frequency calculate by the computer modal analysis larger than the resonance frequency of the measured test values This is due to host the actual shell of the computer by each side made of thin steel plate riveting, and list them in the computer simulation as a whole in the shell, so that the overall stiffness of the system become larger, so that the analysis of the inherent frequency than the actual value. Transient dynamic analysis of the computer meets the fixed-frequency sinusoidal test results，which are all happened in the prophase of vibration in the balance position. This vibration last a period causing fatigue, so that the acceleration package increases slowly and the product damage.

This paper try to predict fatigue based on a GA – BP algorithm. GA algorithm is the ideal tool to cope with high efficient learning methods and optimization for topological structure of networks for BP. Compared the predicted result with the tested result and find that this method has relatively high accuracy.

Zinc oxide nanowhisker (ZnOw) reinforced lead zirconate titanate (PZT) nanocomposites were prepared by a conventional solid state processing. The incorporation of ZnOw has effects on microstructures, electrical and mechanical properties of PZT/ZnOw nanocomposites. Microstructure studies show that ZnOw dispersed in the PZT matrix leads to the decline of grain size and change of fracture mode for the PZT/ZnOw nanocomposites. Mechanical properties of the nanocomposites are dependent upon the content of ZnOw nonlinearly and could be improved significantly with small addition of ZnOw. In particular, the compression and fracture strengths of the PZT/2wt. ZnOw nanocomposites sintered at 1200°C are approximately 180 and 150 of the monolithic PZT, respectively. Electrical properties of the nanocomposites could be evidently adjustable with different additions of ZnOw. The new piezoelectric nanocomposites with good electrical and excellent mechanical properties are promising candidates for further applications.

In this paper, the engine crankshaft remanufacturing life was estimated before and after. As long as the known material properties, loading, local stress, and then select the appropriate fatigue damage model can predict the fatigue life estimation. Material parameters of the experiment and the approximate method are obtained; load is on the basis of dynamic simulation; local stress obtained by finite element analysis; injury models were selected: the uniaxial damage model S-N method and multi-axis model of damage is strain method, SWT-Bannantine method, shear strain method, Fatemi-Socie method. New crankshaft and 500 hours, 1000 hours and 3000 hours after the crankshaft bench fatigue tests were conducted, and the experimental results were compared to verify the correctness of the theoretical calculation, and explain the crankshaft to remanufacture the fatigue life is sufficient.

It is difficult to balance long travel and high precision, especially in multi-coordinate machining. A stage with nanometer positioning precision is established and the control technologies are studied. Micro-EDM provides the potential feasibility for the nano-scale precision machining. The micro-EDM transmission modular is applied to to complete the discharge process of the servo in the experiment system ,which improves the processing efficiency and the processing quality. The strategy is one part of micro-EDM machine control system, which greatly enhances the positioning accuracy. Results show that the system works well. The system also has many advantages such as quick response, being smooth, ultra low speed and super resolution etc, and meets the needs of micro-EDM control. The research provides a new solution for the design of precision location stages.

Tyre tread pattern mainly accounts for tyre performance and its endurance. In tyre mold processing, pattern block processing is technologically disturbing, of which the tread pattern is the most challenging. This article first analyses the function conversion of the points from point to plane to space along the tyre tread curve. Aided by GRIP language, it continues to make tread section with spatial curve, and then with the help of UG scanning order, it produces a three-dimensional diorama of accurate tyre pattern. To solve the problem of large errors arising in tyre mold processing with 3 axis numerical control technology, the article proposes a new method to produce tyre tread pattern with 3 axis technology and validates the method. The research contributes to dividing processing of tyre tread pattern, and reducing errors theoretically. Experiments had been done to illustrate that the method can achieve high quality and efficient processing.

The process of bubbles from formation to eruption was simulated by using the two-fluid model combined with the particle kinetic theory to investigate the flow characterization of gas-solid in a bubbling fluidized bed. The velocity distributions of solid-phase in different axial height were also studied. The results show that the numerical simulation method can success simulates the flow characterization of gas-solid bubbling fluidized bed. The flow characterization in bubbling fluidized bed is circulating flow structure, while the central region is upward flow and the wall region is downward flow. The simulation results agree with the experiment results.

In ultra-precision cutting, grinding and non-traditional machining, it is difficult to balance long travel and high precision, especially in multi-coordinate machining. Aiming at tri-coordinate ultra precision machining, this paper studies the ultra precision machining technology and theory. It attempts to seek the principle in ultra precision machining as well as construct a pilot antitype with the ultra precision tri-coordinate machining system machine.

The paper based on the domestic research result and foreign research result on error compensation, aimed at the geometric feature of a three dimensions micro-EDM stage. By the coordinate matrix transformation method, we have developed the three dimension kinematics synthesis error mathematical model. Then the micro-EDM stage error was compensated. The error model for the stage is simple and error compensation is easy.

A nanometer precision location stage for micro-EDM was designed, which was built by the using of ultrasonic motor as driver unit. The stage precision test was done then. The results showed that the stage worked well and reached high precision. The research provided a new solution about the design of precision location stages.

Micro-EDM provides the potential feasibility for the nano-scale precision machining, and Micro-EDM is suitable for three-dimensional complicated structure processing. A three-dimensional model is conducted in this paper, and the key factors of a platform are analysed in detail, the positioning accuracy of the platform is tested on this basis of the model. The results of the test show that dynamic behavior and stability of this mechanism has many advantages of quick response, smooth, ultra low speed and super resolution etc. High positioning accuracy can be achieved by this platform, so it complies with the requirement of micro-EDM.

In the paper, a micro-EDM prototype was designed, and a preliminary machining experiment was done. The micro-EDM prototype was makeup by three dimensions stage, transistor type isopulse generator with pulse duration of 80ns, and environment maintain system. The machining experiment approved that the prototype in good working order, the stage can reach very high precision, and simple micro-EDM machining was done.

Schematic diagramThe roles of RHHPC with hierarchical pores in the negative electrode of lead-carbon battery.