Applied Mechanics and Materials Vol. 163

Abstract: Taking one of the belt-driven machine tools, horizontal milling machine, as the protagonist, the study constructs a virtual environment based on OpenGL and Microsoft Foundation Class without using any well-developed commercial VR software. Belt-driven mechanism was developed in the 1920s, at which time the motor was first invented and rather expensive. Because of difficult preservation and underlying hazards in mechanical antiques, resurgence of the horizontal milling machine in virtual reality is proposed and an exhibition room is permanently settled to memorize the history of mechanical engineering in the 1920s. Aside from the application of exhibition, this developed system also allows users to operate the machine tool in the same manner as in reality.

Abstract: In the manufacture process of many large-scaled and complex products assembly, due to large number of parts or components, assemblies are often divided into several small assembly units in order to organize production and increase assembly efficiency. To obtain fine-grained rapid assembly unit partition, this paper presents a method of assembly unit partition based on cut-set theory with consideration of the assembly constraints and assembly complexity. The paper also discusses the method of establishing the assembly relationship graph of a product as the basis of unit partition. The relationship graph is extracted from the CAD model of the product and is used to describe the relationship of its component assembly. Using the proposed unit partition method, assembly constraints such as precedence relationship can be considered so that invalid assembly unit partition will be avoided. Furthermore, by defining assembly complexity, optimal selection of assembly unit partition can be achieved. The procedures of assembly unit partition including establishing of assembly relationship from CAD model, approach to cut-set, optimal selection and validation are addressed with an assembly example and a flow chart.

Abstract: In this thesis, an 8-link mechanism was design to simulate a real horse running leg. The 8-link type has been decided first, than the solution plane method has been used to the linkage synthesis. A computer software has been developed to solve the given loop equations. This software can give the profile of the mechanism and the information of the link length and the moving curve of the decided touch-ground point quickly. Several 8-link mechanisms were presented according to the designers choice. The results show that this method as well as software is able to develop complicate 8-link mechanism freely and correctly.

Abstract: This paper provides a method of automatic design for extendable truss based on CAD software. The method mainly consists of parametrical design, automatic assembly, interference checking and extraction of model properties. With Visual C + + as programming language, secondary development was done on automatic assembly and other related modules of CAD software, which can achieve parametrically automatic assembly, interference checking and automatically extracting properties of extendable truss model. Thus, this method can guide the design staff performing program design, improve the correctness and accuracy of design, shorten the design cycle of extendable truss and also has reference value on rapid design and development for other products.

Abstract: In order to reducing motors energy consumption, the problem about motion function, which has torque feature (AV) m small, is discussed in this paper. Conventional functions and small torque moment function are used to control mass center motion of robot ZQROT-I respectively. In the process of robot running the straight gait , motion performance of the robot is analyzed by ADAMS. Analysis result indicates that function controlling mass motion of robot with small torque feature has significant meaning for saving working energy of robot.

Abstract: Characteristics of contemporary aircraft manufacturing are small batch, line-unit production and collaborative development. The consistency of product data is emphasized in collaborative development pattern. In order to meet the demand to share product data by designers, planners and quality inspectors in engineering change process, configuration-based and consistent product data model in different phases of development was established. A method is proposed that describes the evolvement of product data model and version in whole life cycle,and it supports configuration management. Multi-view and multi-dimensional display of product information was implemented.

Abstract: For project-based learning model in course of electromechanical Control Engineering, the method of using graduate students as teaching assistants is proposed to resolve the problem of shortage of teachers. In mechanical engineering institution, graduate students undertake all kinds of teaching works after strict selection and comprehensive training and the advantages of graduate assistants are fully taken. This system makes great contributions to the teaching of the Electromechanical Control Engineering and achieves positive evaluations from teachers and students. For the problems in teaching system, corresponding solutions are proposed and good teaching effects are achieved in actual teaching process.

Abstract: According to the example of using a common grinding and composition of parts processing movement and achievement elements, the design of construction of special NC technologies in ordinary grinding machine was formulated. . The grinding and polish-grinding were performed by using two NC systems in series to achieve multi-axis movement. The function and application scope of NC technology were expanded because the instantaneous compensation of the grinding wheel and the polish-grinding wheel were performed under a rectangular coordinate system and a polar coordinate system by using an open loop NC system. The application of surface recovery of grinding wheel by NC reconstruction and extension applications of processing the track of involute curve were referred.

Abstract: Nowadays automobiles are with good performance and comfortable; however, safety gradually becomes an issue because of high incidence of traffic accidents. Except for occupants injured in traffic accidents, other vulnerable road users, like pedestrians, are also in danger. Pedestrians make up 16% of all road traffic fatalities in the EU and over 30% in Japan, their percentage can exceed 50% in developing countries. In nonfatal car-pedestrian accidents, lower extremities are the most commonly injured body parts.EEVC proposed sub-system tests to evaluate responses and injuries of pedestrians in lateral car-pedestrian accidents, in which lower legform to bumper tests are used to investigate leg injuries. Now the TRL-PLI and Flex-PLI have developed, and both have their pros and cons. In this study it is to modify existing lower legform impactor model, and the new model is still with high biofidelity, inexpensive and easy to manufacture and assemble. The new model can then be made physically and applied to relevant tests and development of pedestrian passive safety system.In order to ensure the biofidelity of new legform impactor model, it is needed to conduct certification tests. Setup and biofidelic corridor of certification tests are based on PMHS tests. This study constructs the finite element model of human-like legform impactor model and makes use of LS-DYNA to perform the same tests as PMHS to evaluate its biofidelity. Certification tests consist of component and assembly tests. Component tests include 3-point leg bending tests and 4-point knee joint bending tests, and assembly tests comprise shearing and bending tests, all above in lateral direction. After finishing all the certification tests, testing results are analyzed and compared with those of two existing legform impactors. One legform to bumper test is conducted as a case of application.

Abstract: The synthetic stiffness measurement principle of Armature Components which is similar to the actual working condition has been proposed. The synthetic stiffness measurement system based on the measurement principle has been established, the composition of this system has been introduced and the realization methods of the single couples loading and torque and angle measurement has been introduced in detail. And related experiments has been conducted. Through analysis the experiment data, the performance of organization has been tested, and so does the rationality of the measurement principle which is proposed.