Advanced Materials Research Vols. 139-141

Abstract: The paper takes computer digital image processing as a foundation, laboratory analysis as the confirmation method, and takes garment industry production as the application production, researching the information characteristic of the clothing image design, the signal extraction, and the basic conversion rule in order to explore the computer-aided design of clothing pattern, apparel images (CAD), as well as the achievement of automatic laser cutting on complex design and apparel-hanging through the information technology. The topic emphatically discusses different graphic file format conversion technology and establishes the best craft parameter database that suits the laser cutting via the ACCESS software, while carrying on the shape error and precision analysis. The topic research conclusion will provide effective, reliable technology and the data support for the laser cutting craft in fashion industry. And it will enhance the laser processing efficiency of the fashion and the apparel hanging as well as guarantee the cutting quality to achieve the best effect.

Abstract: The process of particle impacting and contacting curved surface of vane was studied, and the characteristics of particle size, particle initial velocity and its impacting direction affect the stress of subsurface were analyzed by using ANSYS/LS-DANY software. It is shown that the interaction between particles and surface of vane is affected by nonlinear factors such as the elastic-plastic property of material, the state of impacting and contacting and surface shape. The increment in particle size increases the stress of the surface impacted and the sphere of action is also enlarged. The influence of the size of particles is remarkable. Particle impact velocity is related to energy exchange and has influences on stress value and the area of surface deformation. Due to impact angle is related to shape of curved vane, so the distribution of stress is changed and the value of the stress in surface layer is also influenced when particles impact curved surface of vane from different directions. The research will be helpful to disclose the mechanics of the wear on the condition of particle impact.

Abstract: Based on the analysis and study of the composite reducer, the allocation of transmission ratio is considered to be the key to optimal design of multi-level planetary gear reducer. In view of so many discussion and study of the minimum volume as the optimization objective existed, this paper regards the maximum load capacity as the optimal goal on condition that the center distance or size is given, and then establishes the optimal mathematical model. The related constraints are given according to the theoretical knowledge and practical design experience. In this paper, an optimal function procedure that based on genetic is used to optimize the mathematical model. The satisfied result has been worked out combined with the practical example. Compared to the original program, the load capacity of 17.8% is improved. In addition, some references are provided to the optimal design of planetary gear reducer.

Abstract: This article proposes a method of three-dimensional modeling based on voxel code, which can build three-dimensional model by means of cubic voxels and Voxel code. Voxel code is the one that records the formation of physical location of the voxels piled up in turn order in the body. The different Three-dimensional shape can be constructed according to different codes. In order to reduce the storage overhead of the code, the linear octree coding and decoding are given in recording voxel code. Combined with VTK (Visualization Toolkit) programming, some voxel models have been visualization. The modeling idea and method proposed in this paper have a positive significance for the promotion of the research and development of related science fields and have their theoretical and practical value.

Abstract: Cutting parameters including cutting speed, feed rate, depth of cut and the number of passes have significant influence on both machining quality and machining economics. Cutting parameter optimization involves optimal selection of a combination of these parameters. It is an essential part of a computer-aided manufacturing system. In this paper, an optimization model based on minimum production cost for multi-pass turning operations is developed. Various realistic machining conditions and machining requirements are incorporated in the model as constraints. Optimal solutions are found by a nonlinear programming solution approach. A turning example is presented to test the model. Compared with the literature and the cutting regimes recommended in machining data handbook, our model and solution method are simple and generate much lower unit production costs.

Abstract: To achieve the accurate duplication of product in reverse engineering, we proposed an algorithm for generating multi-axis NC machining tool-path directly based on scattered point cloud. At first, we obtained the neighborhoods of tool-path section based on the dynamic spatial index of scattered point cloud and from which we selected the matching points. Then the tool-path section points can be obtained through intersection of the tool-path section and the lines which link the matching points, and the normal vectors of tool-path section points can be calculated based on the differential geometry property of local reference data. Finally we computed the cutter location points by means of projection method and sorted them based on the minimum spanning tree algorithm to form the tool-path. With the results of several experiments, the high precision and efficiency of this algorithm are verified.

Abstract: A six-axis CNC belt grinding machine automatic programming technology was studied in this paper, and which used D-H rule to solve out five-axis motion variables (the DOF of A, B, X, Y, Z), then discussed the problem of maximum contact degree between the grinding wheel and contact surface, and solved out the C-axis motion variable (the sixth DOF) by the direction of principal curvature in each cutter location point, after that gave a modified method of C-axis motion variable to smooth the machining. In order to ensure the machining accuracy while improving the machining efficiency, the paper summarized the self-adaptive spacing and step distance calculation method. The results which verified by a simulation analysis were validity and reliability, and provide a new thinking and beneficial reference for the research of other similar NC programming technology.

Abstract: Based on analyzing the shortcomings of the current product development mode and methods of the automatic transmission, and on the principle of virtual prototype technology(VPT) and the thought of business process re-engineering (BPR), a concurrent development flow model suitable for virtual automatic transmission prototype(VATP) was established. The function model and the architecture of the platform for developing the VATP were also described in detail. Finally, the ideas for solving some key technological problems faced during implementing the platform were discussed in this paper.

Abstract: On the basis of scale-based modular product family design method, the customization product CAD/CAE integrated system was studied under mass customization environment. The system divides into three parts including programming, design and evaluating process. First of all, product family model was built during programming process, which includes functional model, principle model and structure model. Then based on the product family model database, in accordance with the theory of variant design, using parametric CAD re-development technology, specific product satisfied by client customizes rapidly. Finally utilizing finite element analysis to analyze and evaluate the customization design, the customization result will be more reasonable and high efficiency.

Abstract: Due to shortcomings existing in traditional overlapping model, a new extending activity overlapping model based on design structure matrix considering rework and iteration during activities execution is proposed in this article. Firstly, a tradional overlapping model presented by others is introduced. Sencondly, it is expanded to apply to more general situations using design structure matrix. Subsequently, an example deriving from a certain product development process is used in order to illustrate its effeciency and effectiness