Advanced Materials Research Vols. 139-141

Abstract: The nonferrous alloy castings will be much demanded with the development of aerospace, light-weight weapons and automotive industry. Casting CAD/CAE technology has played an increasingly important role in foundry. It can help technician to design casting process and simulate heat transferring and molten metal flowing before actual production. Firstly, the main contents and basic principles, mathematical models of casting CAD and CAE were introduced. Secondly, the casting CAD/CAE technology route was interpreted, and then several CAD/CAE applications of casting process design and simulating were carried out on nonferrous alloys, such as aluminum, magnesium and copper. The results indicate that CAD/CAE technology can be applied to casting process design and predict casting defects which usually occur during the casting mold filling and solidification process, it can provide references to optimize casting process, so as to improve casting quality, reduce the rejection rate and shorten the development cycle of new products.

Abstract: Using ObjectARX, an integrated CAD/CAM software for steel tubular truss structures has been developed based on AutoCAD platform and Visual studio.Net environment. The design ideas and the application effects are introduced in this paper. Because of different data requirements in different design stages of steel tubular structures, i.e., the whole structure design and the detail design, a wireframe model and a solid model were adopted in the software, respectively. Joint lofting is the key point in manufacturing of complex tubular trusses. To solve this, 3D solid model was constructed by self-defined solid objects, which were designed with inheritance of class AcDb3dSolid in ObjectARX, and Boolean operation was used to realize 3D end lofting of branch pipes. Based on the lofted solid model, the G-codes can be generated automatically. At last, an actual tubular truss structure was designed and lofted by using the software. The proposed software package realizes the integration of CAD/CAM and it can greatly reduce the cost and time of design and fabrication, improve the quality of construction.

Abstract: The hydraulic cylinder is an actuator of hydraulic lifting system in the heavy tipper, which also plays an important role in unloading. Aiming at the existing multistage hydraulic cylinder design method's insufficiency, the CAD/CAE technology is introduced into the domains of multistage hydraulic cylinder design. In this paper push-forwarding five-stage hydraulic cylinder is designed, and virtual assembly is established based on three-dimensional digital model using PRO/E sofeware. The multistage hydraulic cylinder's load-supporting characteristics are analyzed by ANSYS. The result of finite element analysis shows that the stress on the top front part of three down hydraulic cylinder is biggest, those on the trunnion and the cylinder's bottom are also bigger. It is also proved that the multistage hydraulic cylinder designed with CAD/CAE technology can satisfy the requirements of intensity, rigidity and supporting stability.

Abstract: To improve the design efficiency of product, the variant design method of assembly is researched. Firstly, the identifying and extracting method of assembly constraints is researched, and an identifying and extracting method of assembly constraints based on the re-development technology of SolidWorks is presented. With the identifying and extracting method, assembly constraints are obtained and a relationship network of them is built. Secondly, a method for dimensions to transfer around the relationship network of assembly constraints is researched and a dimension transfer method is put forward. Then a dimension modify method of assembly based on the dimension transfer method is obtained. Lastly, a variant design method of assembly based on the dimension transfer and dimension modify method is presented and a variant design module integrated into SolidWorks is developed. As an example, all methods are applied to a coupling assembly, and the methods are verified.

Abstract: Product variant design is one of the key technologies of Manufacturing Enterprise for responding market demand. During the product variant design, dimensional tolerance variant design plays an important role. However, dimensional tolerance variant design is considered rarely in the researches of product variant design. To solve the dimensional tolerance variant design during product variant design, information expression, extraction and labeling method of dimensioning of dimensional tolerance of part dimension model is investigated. A variant design method with dimensional tolerance is presented in this paper. In the method, dimension variant design and dimensional tolerance variant design are integrated, so dimension variant design and dimensional tolerance variant design are implemented concurrently. A part variant design module with dimension and dimensional tolerance based on SolidWorks is developed for using Visual C++. Finally, an example of shaft illustrates the proposed method.

Abstract: In order to improve the logistic characteristics of products, a process of product innovative design for logistics is presented which is combined with the idea of product design for logistics and innovative design theory. Some innovative design approaches i.e. TRIZ, QFD, knowledge-based innovative design, are introduced. Based upon product design criteria for logistics and QFD (Quality Function Deployment), the conflicts between product performance and logistic characteristics are discussed and determined. TRIZ (Theory of Inventive Problem Solving) is employed to solve the conflicts, with the conflict matrix and inventive principles. According to the product logistic characteristics, the general TRIZ engineering parameters are simplified to facilitate the application. Further more, the analysis of logistic design conflicts is introduced. A case study has been done to illustrate the method proposed in this paper.

Abstract: In order to study creative design technology based on multi-domain knowledge-driven, it has been proposed that a novel method of knowledge classification to support product creative design. This method, using the theory of cognitive psychology classifies knowledge into explicit and tacit knowledge, analyzing knowledge transfer and knowledge creation, combining the characteristics of product design, builds up a creative knowledge supply model by constructing a continuous pedigree of creative design. On this basis, the knowledge supporting creative design has been divided into four types: scientific effect, factual knowledge, knowledge of creative design principles, strategies and methods, and personal tacit knowledge. The types and scope of knowledge have been also discussed in different conceptual design stage. The classification provides a theoretical basis for establishing knowledge system of product creative design.

Abstract: It has been discussed in this paper that the necessity of knowledge support technology used in creative design of electromechanical products. In order to apply knowledge support technology to creative design of electromechanical products, a relation matrix has been constructed by QFD (Quality Function Deployment) technology between the various performances of electromechanical products and the involved knowledge of them. Thus, the HOQ (House of Quality) about the knowledge–performance of electromechanical products is built. Then, the further demand tracking has been made as well. After that, it has been established that the knowledge model and knowledge application process used in creative design of electromechanical products. Finally, a new method has been proposed which can guide designers to do product creative design by knowledge demand.

Abstract: This paper proposes a modification method for tooth surface of face gear drive with a grinding worm on a numerical grinding machine. The surface equation of grinding worm is derived, and the coordinate System of generating the worm is established. Tooth contact analysis (TCA) is performed to investigate the performance of face gear drive before and after modification, and the alignment error is considered. This method can obtain a more stable bearing contact in contrast to the method by increasing tooth number of shaper. The longitudinal bearing contact on the face-gear tooth surface has been obtained which will increase the contact ratio. By modification the edge contact at surface edges of the gears can be avoided and the modification magnitude can be controlled freely.

Abstract: Image processing algorithms are based on the idea that all pixels of it ranked over the orderly rows, which make the algorithms easier to be implemented. Extending image processing algorithms to triangular mesh is always an important idea for triangular mesh processing. But since the topology of a triangular mesh is not as simple as an image, triangular mesh processing is relatively difficult. This paper presented a new sphere image representation of a triangular mesh, which is an image as well as a graphic, and based on it, image processing algorithms can be easily extended to a triangular mesh. Experimental results show that by simply extending the image processing algorithms the presented sphere image representation can effectively reduce difficult of segmentation and mesh editing. Moreover the sphere image representation can be used for more triangular mesh processing applications.