Applied Mechanics and Materials Vol. 442

Abstract: The paper created a kind of new transmission way of chain, and applied it to a kind of crawl installation, which has realized installations rotational motion around a space big disc. Pneumatic motor played an important role in the program. This new chain transmission made use of pneumatic motor to drive sprocket, and applied cylinder to control sprocket and chains meshing and separation. It can satisfy demands of chain and sprocket with the variations of work conditions. It proves working course and the principle of this kind of transmission way in detail in the paper.

Abstract: The existing technology of stretching and forming metal honeycomb processing has obvious deficiencies. In order to develop metal honeycomb with high strength and better performance, this paper did extensive research on the technology of semi-regular hexagon corrugated structure forming and overlay process. Modern mechanical methodology was then employed to optimize high strength metal cellular automatic equipment and the best principle schema was selected. Each modules structure of the high strength aluminum honeycombs automatic overlay assembly equipment has been designed. Products were made based on the new design and went through a series of tests. The results demonstrated that this new method has greatly resolved the existing problems regarding the processing technology of aluminum honeycomb.

Abstract: During laser welding process of high-strength galvanized steel, adopting guiding arc plate and the connecting arc plate can avoid harmful effect resulted in unstable melting width. The galvanized layer protecting joint is inevitably lost by having been burned, which affects stain resistance of welding joint. So salt water with the concentration of 3% is used in the corrosion test for the samples welded under different laser parameters, mass variation and metallographic microscopes are gained after joint being corroded. The test results indicate that the corrosion rates of the joint are different under different welding parameters during laser welding of high-strength galvanized steel; their average corrosion rates are coincident with that of base metal and laser welding technology hardly effect corrosion resistance of the joint.

Abstract: Uninhabited Combat Air Vehicles is a complicated global optimum problem. In this paper, according to the characteristics of Uninhabited Combat Air Vehicles, an improved bat algorithm was used to solve Uninhabited Combat Air Vehicles. The algorithm was experimented and the experimental results show that the improved algorithm to be successful in locating multiple solutions and better accuracy. Simulations and results indicate that the improved bat algorithm has better feasibility and validity for solving the multiple UCAV.

Abstract: A method of structure optimization for hydraulic press is proposed in order to reduce mass while assuring adequate stiffness. Upper beam and lower beam are determined as optimal objects by mass analysis. Key geometric parameters of upper beam and lower beam which have relatively larger impacts on mass and stiffness are extracted as design variables. In order to research relationship between stiffness, mass and design variables, command batch file is built by python language to implement automatic finite element analysis in ABAQUS. Orthogonal experimental design is used to generate samples of design variables. Calculating data are dealed with second order stepwise regression and mathematical model for structure optimization is established by regression equations. The goal of structure optimization is to decrease total mass of hydraulic press while assuring adequate stiffness. Particle swarm optimization is used to solve the mathematical model. The total mass of hydraulic press is decreased by 3.1% and its stiffness is adequate to ensure the forming precision when solving process is finished.

Abstract: This Paper designs a mechanical device for the manipulator of the watermelon picking machine against the low mechanical degree of watermelon picking machine. The mechanical device utilizes a mechanical arm to drive the end effector to run and the end effector is responsible for clamping and shearing watermelon vines, which avoids vine disturbance and sorts out vines to be easily cut down through the process design of clamping, promoting, and re-shearing. In addition, this Paper applies Pro/E modeling, finite element analysis, and simulation analysis to complete the 3D model design of the mechanical device and transforms the 3D model into 2D drawings in Auto CAD to complete the manufacturing and assembly of the manipulator, and the test result verifies the mechanical device may realize the reliable picking of watermelons.

Abstract: A robust method based on dual back-propagation neural networks (BPNN) is proposed to recognize light-emitting diode (LED) dies on wafer planes in vision-based LED sorting system. To improve the recognition accuracy of LED dies, particularly under the condition of LED die image degradation, a dual BPNN with 3 layers architecture is first constructed, in which the two BPNNs are trained respectively using the region features and edge features of die images based on batch gradient descent method, and then the outputs of the dual BPNN are fused according to Dempster-Shafer (D-S) theory to generate a final decision. Applying the trained dual BPNN as a classifier, the recognition experiment of a large-diameter LED wafer is completed, experimental results show that LED die recognition accuracy of the dual BPNN is higher than that of the single BPNN based on the region feature or edge feature and is robust to die image degradation, it can be used for LED die array location in vision-baesd LED sorting machines.

Abstract: Key technology for the transmission system of wind turbine condition monitoring is researched in this paper. It gives a summary overview, including monitoring methods, signal processing methods and state recognition technology, data acquisition and transmission technology, programming languages. Understanding of the progress of the field is to provide technical reference and research inspiration for insiders.

Abstract: Under complex electromagnetic environment, various equipment is likely to be disturbed by electromagnetic pulses and to fail. In order to increase their immunity ability of electromagnetic pulses, the electromagnetic protection method based on the sorting technique was proposed. Through signal transform in signal level using the sequence difference histogram sorting algorithm, signal is separated from electromagnetic pulse. So these equipment were protected finally. Experimental results and simulation demonstrate that the method is effective.

Abstract: This paper discusses the principle of ensilage in twining type of straw bundle cylinder, and necessity of developing the machine twining for plastic film round straw bundle cylinder. With combining with domestic actual production requirements, the rational distribution and optimization design are carried out for the machine twining for plastic film round straw bundle cylinder.