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Tang H.Q.,Guangdong University of Technology | Tang H.Q.,Guangxi University | Wang C.Y.,Guangdong University of Technology | Wang B.,Nanjing Research Institute for Agriculture Mechanization | And 3 more authors.
Advanced Materials Research | Year: 2011

The target of this paper is to design a high speed drilling machine suitable for printed circuit board with micro-hole of 0.1 mm diameter, which has drilling force measuring function and rapid change spindle function. Therefore, in this paper, the main principles of module partition for drilling machine were analyzed. Module partition was conducted for high speed drilling machine of Printed Circuit Board (PCB), as well as using modular components combine PCB high speed drilling machine. Then, performance testing and simulation of dynamic modeling were carried out on the modular PCB high speed drilling machine. The results show that the modular PCB high speed drilling machine has good performance, enough stiffness, better stability and meeting the design requirements. The modular partition laid the foundation for further study on the module creation and reconfiguration of PCB drilling machine.

Chen C.,Nanjing Research Institute for Agriculture Mechanization | Chen C.,Anhui Agricultural University | Xue X.,Nanjing Research Institute for Agriculture Mechanization | Gu W.,Nanjing Research Institute for Agriculture Mechanization | And 3 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2015

During the boom sprayer spraying, the vibration of the boom excited by field ground roughness not only influences homogeneity of spray distribution, but also reduces the life of the sprayer. To improve the structure dynamic behavior of the original boom design, a multi-variable optimization approach by genetic algorithms was presented. A parametric finite element model of the 18 bar plane truss element was built by the finite element software Abaqus. Then the mass of spray boom is taken as optimization goal. The first mode frequency of spray boom is taken as constraint condition. The element node coordinate and section dimension of spray boom are taken as design variables. All the design variables are transformed to dimensionless variables based on the unified design variable method to avoid optimization analysis failing to converge. The design variables and the optimization goal of the model were set on the Isight multidisciplinary multi-objective optimization platform, the shape of the boom structure and bar section dimension were optimized by using Multi-Island Genetic Algorithm (MIGA) method to obtain a single lance structure with 10.87 Hz first mode frequency, 35.82 kg mass and 5 m width. According to the technological requirements, the optimized structural dimensions were adjusted to manufacture an actual sample. In order to ensure the reliability and accuracy of the finite element model, the modal test in impact method was done to validate the finite element model and its modal parameters. In the test, the boom was fixed on the concrete column to make the actual model consistent with the finite element model. Single-point excitation and multi-point acquisition method was used. The exciting signal was generated by an impulse hammer and the response signal was measured by acceleration sensors. Then the modal parameters were identified in the computer. After the test, a comparison between test and simulation was made. The result showed that the difference of first 6 modes frequency between finite element model and test modal model were all less than 10%, the modal assurance criterion (MAC) of the first 6 modes between finite element model and test modal model were all more than 0.85, which indicated that the finite element model and the modal parameters of the model met the requirement of engineering research. Since the spray boom was fixed on the tractor chassis frame, the oscillation of chassis from ground roughness would directly transfer to the spray boom, which may lead to spray boom's vibration. A rigid-flexible coupling sprayer virtual prototyping is established in Abaqus to compare vibration displacement between the spray booms before and after optimization. Generally, hose laid was used in the pesticide transport, which has little impact on spray boom structure dynamic behavior. So the pipeline and nozzle was substituted by the uniform distribution mass in the sprayer model. Random vibration response was analyzed under the excitation of power spectrum density (PSD) of the class D road at the tractor speed of 20 km/h. The result showed that the maximal vibration deformations at the end point of the spray boom were about 7.9 mm and 9.5 mm relative to the static condition before and after optimization respectively. The deformations were all less than 10mm. The maximal deformation after the optimization was not increased obviously with the mass of the optimized spray boom was decreased by 48.43%. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.

Xue X.,Nanjing Research Institute for Agriculture Mechanization | Lan Y.,South China Agricultural University | Sun Z.,Nanjing Research Institute for Agriculture Mechanization | Chang C.,Nanjing Research Institute for Agriculture Mechanization | Hoffmann W.C.,U.S. Department of Agriculture
Computers and Electronics in Agriculture | Year: 2016

To perform plant-protection operations, an unmanned aerial vehicle (UAV) based automatic control spraying system was designed in China. The system used a highly integrated and ultra-low power MSP430 single-chip micro-computer with an independent functional module. This allowed route planning software to direct the UAV to the desired spray area. The test results of route precision showed that in a 3–4 m/s crosswind, route deviations were around 0.2 m. The result of multiple-spraying swath uniformity tests showed a minimum coefficient of variation of 25% when flying at a height of 5 m with a spraying swath of 7 m and a wind speed of 0–2 m/s. When the spraying swath was 9 m or 5 m, the coefficients were 34% and 41%, respectively. Spray uniformity for these UAV tests were superior to the Standard Requirement for ultra-low volume spraying variation coefficient, 60%. © 2016 Elsevier B.V.

Xue X.,Nanjing Research Institute for Agriculture Mechanization | Lan Y.,Southern Plains Agricultural Research Center
Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery | Year: 2013

The United States has the most advanced equipment and applications in agricultural aviation. It also has a complete service system in agricultural aviation. This article introduced the current status of aerial applications including service, equipment, and aerial application techniques. It had a complete system including various components for aerial applications which could fit into the different applications. It had practical application of different advanced technologies such as GPS autonomous guidance, variable rate technology, and application models. This article also summarized the techniques in remote sensing, spatial statistic, and variable rate controls, and how these technologies had been used in yield estimation and monitoring for crop water and nutrient stresses, and also pest damages. This article also showed the current status of USA precision aerial application and also provided some thought of the future direction in precision aerial applications including real-time imaging processing, variable rate technologies, and multisensory data fusion.

Wang S.-Z.,Nanjing University of Science and Technology | Wang S.-Z.,Nanjing Research Institute for Agriculture Mechanization | Lu B.-C.,Nanjing University of Science and Technology
2015 5th International Workshop on Computer Science and Engineering: Information Processing and Control Engineering, WCSE 2015-IPCE | Year: 2015

Combine harvester is generally used machinery equipment. The design, production and using of combine harvester must ensure grain loss meeting its relevant national indicators of quality and performance. Grain loss mainly come from cleaning parts, so that the research of cleaning loss detection technology is very important. But the combine harvester monitoring system about loss is not universal, basically staying at the research stage in China. Under our existing land conditions, with combine existing holdings, the research value and market prospects are very impressive. From the signal acquisition technology ,signal processing and extraction and vibration sensor structure, this article introduces the domestic and foreign harvester method and apparatus for testing the cleaning loss. It Also analyses the problems of existing research technology and methods, including the complex calibration procedure of sensor and detection devices ,not being high detection accuracy and so on. On this basis, the author puts forward the main research directions of cleaning loss detection technology and its development trends in the future. Firstly, the key sensor technologies are developed in depth. Secondly, application of blind sources separation(BSS) and other signal process technology in the grain cleaning loss extraction. Lastly, research on loss mechanism and automatic controlling technology for cleaning part.

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