Key Engineering Materials Vol. 522

Abstract: The curve intensity of deddendum plays a significant role in gear strength design. Due to the complicated shape of gears, traditional method utilizes the cantilever beam model adds the concentrated load at a fixed point and then revises it by coordinating with different factors so as to calculate the gears the curve intensity of deddendum. In this paper, based on evolute formulas, a methodology about finite element analysis was used for establishing the accurate tooth profile model of the evolute cylinder gear. The moving load was added by programming and the regularity that the amplitude of load changes with the position of the point of application in a tooth meshing cycle was determined. Based on proposed model, this paper provides the variation regularity of the magnitude of the stress of deddendum by simulation.

Abstract: LOS of the stabilized sighting system is the benchmark of its working. When the stabilized sighting system is installed on the moving carrier, its LOS stability is affected by changes of the posture of the moving carrier. Therefore, a stabilizing device in the stabilized sighting system needs to be designed to isolate the impact of these disturbances on LOS stability. In the paper, firstly, it is introduced the stabilized sighting system working principle. And then, considering from several aspects of optical system, mechanical structure and gyroscope installing location presents three kinds LOS stabilizing methods as whole stabilization, gear transmission stabilization and reflector stabilization. And, it is analyzed for each method and compared with the advantages and disadvantages in detail. These lay a good foundation for the design of the stabilizing device of the stabilized sighting system.

Abstract: This paper studies a load simulation system based on permanent magnet synchronous motor. Vector control principle of the loading motors vector control technology is analyzed, and using the strategy that direct-axis component of the stator current is zero, the mathematical model of load control is established. To analysis the control characteristics and lay a foundation for the control algorithm of the system, the control channel is divided into two channels, namely the forward load channel and disturbance channel, whose characteristics are analyzed, too. The torsional stiffness of the connecting link has an effect on the dynamics characteristics of the system. Therefore, the system dynamic characteristics under different torsional stiffness of forward load channel and disturbance channel are analyzed in the paper.

Abstract: Because of the universality, complexity and uncertainty of mechanical design knowledge, knowledge reasoning and integration of intelligent design system was one of the difficult problems. The valuation of weight by human was used in many methods for knowledge reasoning at present. In order to make the intelligent product design become more scientific and rational, and eliminate the subjective human factors, a method for reasoning using information entropy was proposed. First, by means of the advantage of the relational database include the redundancy, consistency and integrity, the mechanical product design knowledge base was established. Second, based on the information entropy theory, the weight of each attribute was calculated directly through the objective information. Third, based on the objective data in the original sample, the method for calculating the similarity between accurate attributes and uncertainty attributes and design schemes was given. Finally, this method was verified by fruit picking robot intelligent design system, and the result showed that it is objective and effective.

Abstract: The collaborative design and manufacturing is applied in the aircraft industry. This paper introduces the collaborative design and manufacturing mode in aircraft industry and presents its structural framework. The data is managed in the structure of BOM and there are two ways to share the data between the suppliers. The collaborative design and manufacturing process reflects the concept of concurrent engineering. The collaborative design and manufacturing system has been applied in the project of C919 which could sharply shorten the research cycle and reduce the product cost.

Abstract: In recent decades, the rapidly development of wind energy in China and the increasing of size and complexity of wind turbine have requested the improvement in wind turbine systematic design technology. A reasonable systematic dynamic model is an important part for systematic design of MW-class wind turbine. In structural dynamic model, the flexibility of blade and tower is represented by presumed mode shapes. In this paper, based on presumed mode shape method, the structural dynamic equations of wind turbine were constructed. Along with the wind field model, the wind turbine aeroelastic systematic dynamic model was constructed. Using the model, the deflections and load of blade, low speed shaft torque of a 1.5MW wind turbine have been calculated. Therefore, the construction of wind turbines systematic dynamic model has an important significance for the development of wind systematic design and manufacturing capacity.

Abstract: For the development of Chinas cotton picker, this paper focuses on researching the level of spindle-type cotton pickers principle and the law of motion. It established overall model of motion simulation and got the contour in the motion simulation module, then extract the line data and make data processing on the basis of the MATLAB, making reconstruction in the three-dimensional modeling software through applying function expression derived from Matlab. In the motion simulation module, getting the displacement, velocity and acceleration curve charts and discussing their analysis, so as to provide the well-reference value for research law of motion in the pick roller of cotton picker.

Abstract: Precise cable drive has been developed as an alternative transmission element to gearbox, belt and pulleys, chains and sprocket in Electro-Optical Tracking system. Precise cable drive has several significant advantages including backlash free, high stiffness, high efficiency, no lubrication etc. This paper develops analytical methods to predict the transverse oscillation frequency of precise cable drive to enable designers to better assess dynamic performance in the design study phase. Theoretical formulation of transverse oscillation equation for precise cable drive is carried out based on Hamiltons principle taking into account flexural rigidity of cable. Furthermore, the transverse oscillation frequency is obtained from the transverse oscillation equation assuming small and linear vibration. Parametric studies are conducted to evaluate the relationship between the oscillation properties and cable drive parameters.

Abstract: The primary parameter of the track circuit is often the test data in the maintenance of the signal, is the important basis for designing equipment of track circuit and is the basic parameter of track circuit parameter, primary parameter of track circuit can be used for rail simulation experiment of track circuit parameters, analysis of rail leakage and calculation of track circuit. This paper studies the primary parameter of track circuit test method, the result can be used for calculation track circuit parameter.In the practical application, primary parameter of track circuit test can have positive significance in the division of track circuit district and the adjustment of working state.

Abstract: There are four fluid flows in the water regulator of injection wells the first the second the third and the forth backwash flow.The four fluid flows are used to injection and backwash petroleum wells.Based on the reliability of the water regulator under the high-pressured high speed fluid's function.By using fluent software for the numerical analysis and fluid dynamics,get the velocity and pressure field contours and the cloud chart,under the high pressure and high velocity effect. Meanwhile analysis the results.It is provide a theoretical basis for the optimization of the structure of water distribution device.