The concept and main content of collaborative virtual manufacturing (CVM) are presented and relation and difference between CVM and VM are proposed. As the expansion and extension of VM, CVM could be defined as a kind of VM based on network, database and distributed computing technology, cooperatively participated by manufacturers, suppliers, partners and customers, and supporting supply chain management and personalized services. According to the principles of multi-layer, loose-coupling EAI, and extensibility, considering transverse integrity between enterprises on supply chain and lengthways integrity based on distributed object technology, the architecture of CVM is given. The main inconsistency between CVM and distributed object technology is analyzed, based on which, the main technical content of CVM oriented distributed supporting environment is proposed. A typical frame of CVM oriented distributed supporting environment is provided. In this frame, isomeric distributed object is integrated by Web Service, and the problem of real-time communication is solved by berkeley Socket technology.

According to stress-strength distribution interference and fuzzy theory, research on mechanical reliability and optimization design based on fuzzy design criterion is conducted systematically and the concept of surplus reliability is proposed. The mathematic model of such concept is established and design illustrations are provided. The research result indicates that common reliability design, taking required reliability as the unique objective, has no practical meaning because it cannot consider other conditions' constraints on design variables, which leads to the unfeasibility of design result. Reliability and Optimization Design, taking fuzzy reliability as well as all other conditions as design constraints, circumscribes feasible design field in design space and then explores the optimal design scheme in this feasible field with some method according to design objectives, which can guarantee the reliability, feasibility and optimality of design result.

The appropriate coordination between the fields of mechanical and electrical engineering during early stages of the development allows the improvement of product quality as well as the reduction of development time. This article outlines a method to enhance the communication between the fields of mechanical and electrical engineering for the conception of machine tools. The presented method is supported by an integrated software solution. Therefore, the data generated during the whole process can be filed and digitally processed.

Virtual wiring is presented by adopting virtual prototyping technology in the problems of electro-mechanical product cable wiring. The first step of this method is to establish information of product virtual prototyping, cable connection table, cable interface, cable material, intersection parameter. Based on the above information and regulation of cable wiring, the second step is to layout hoop's location and cable route path, and then to calculate cable length by utilizing virtual prototyping technology's support on visualization and human-computer interaction. And then through particle system simulation, cable's form is obtained and corresponding cable model is generated. On the basis of discussing electro-mechanical product cable wiring and its solving method, this paper focuses on the key technology of information model and virtual wiring of electro-mechanical product. Finally, feasibility of this method is demonstrated through an illustration.

As a typical modern physical property actuator, giant magnetostrictive actuator (GMA) has a wide application prospect in the fields of precision and ultra-precision machining. This method, as a key technology of GMA, could eliminating or restraining adverse influence triggered by rise of temperature and improve GMA's output precision by taking measure of compensating or restraining thermal error of GMA. Aiming at this problem, six methods for thermal error compensation and restraining is presented. Principles of these methods were introduced as well as characteristics and application situations. Meantime, a series of experiments using our phase changing water cooling combination temperature control system are conducted and satisfactory results are obtained. The results demonstrate that the proposed theorems and method can effectively direct research and design of GMA in various situations.

The load-sensing hydraulic system has been applied to construction machinery wildly. The interaction between load-sensing pump, load and output pipe will cause instability of output pressure and flow easily without carefully design, which decreases control accuracy of actuator and even more will causes damage of pipe or pump. The problem is investigated deeply by theoretical analysis and experiment. Especially, the influence of pipe on the dynamic of load-sensing pump is studied. The conclusions are valuable for the design of load-sensing system.

CFD simulation on flowing characteristics of liquid in micro diffuser element in chamber of a new type nozzle/diffuser valveless micro-pump is conducted. Through such simulation, the influences of the parameters, such as diffuser angle, Re number, on fluidic pressure loss coefficient is achieved. The result of simulation indicates that although any given diffuser angle and Re number have a corresponding minimum pressure loss coefficient, pressure loss coefficient will decrease with the increase of Re number when diffuser angle is small while pressure loss coefficient will increase with the increase of Re number when diffuser angle is large.

Aiming at the calculating problem of screw thread connection strengthin engine design, by adopting FEA application ABAQUS/STANDARD, a scheme for accurately computing strength of screw thread area in cylinder block is studied, which means to compute bolt bearing forces under working load through simplified assembly model. The acquired bolt bearing force, regarded as load distribution, will be applied to the local model with thread to compute the thread stress distribution around the bolt and cylinder block. In meshing scheme, the simplified cylinder block and bolt, divided into two parts in local model, were meshed by hexahedral elements to save computation cost and improve computation accuracy. Finally, stress distribution for thread in engine cylinder block in pre-tension load case and peak-combustion-pressure load case are calculated and analyzed to verify this method. It provides a way for design and calculation of thread connection in engines and gives reference to the practical application of related project.

The optimization design model of 2-stage star gear transmission is established. Transmission mechanism and restraint conditions were analyzed. Principal optimization design parameters are determined by taking minimum center distance as objective function. The optimization design method, which takes tooth number, modulus as discrete variables and modification coefficients as continuum variable, is adopted. Result of optimization design is badly influenced because of too many equation restraints, which reduce the feasible regions or even reduce them to zero. Therefore, a complex mode optimization method is developed. By taking tooth number and modulus as discrete variables and modification coefficients as continuum variables,by adopting nonlinear multivariable function fmincon in Matlab program, main optimization design parameters are gained.

According to the characteristics of cylindricity error evaluation, the computation methods of objective functions' mathematic model is established whe
n adopting Minimum Zone Cylinder (MZC), The Least square Cylinder (LSC), Minimum Circumscribed Cylinder (MCC) and Maximum Inscribed Cylinder (MIC) to evaluate cylindricity error in Matlab. Through comparing with the multi-evaluations of cylindricity error using different methods with different initial values, this method is proved that it can converge to an overall optimal and steady result. In addition, this algorithm can be extended to other forms' error evaluation.

A tiny step distance control method is proposed and this method successfully solves the problem of implementing tiny step distance control of step motor with high accuracy. This method is capable of highly accurate orientation of step motor and greatly enhancing its resolution and dynamic operating property. By adopting this method, the technique of tiny step distance control has been elevated to a higher level.

Research on structural behavior of cylindrical shells in column-supported steel silos under wind loading by adopting numerical methods is conducted. Firstly, distributions of circumferential wind pressure on cylindrical shells are summarized. Then, research on structural behavior, especially stability, of column-supported cylindrical shells is carried out through linear stress analysis and geometric nonlinear analysis. Furthermore, analysis on effect of column width is conducted. Finally, original imperfection sensitivity of column-supported cylindrical shells is discussed.

Based on the pre-process of body model, this paper defined feature points according to the method of body measuring science. Focusing on the distribution rule of feature points, a searching method based on changeable step size was presented. This method performed well in both speed and accuracy, and could finally acquire feature sizes and generate body skeleton according to the location of features points.

Drawing layout will directly influence drawing quality in automatic CAD drawing system. Through using expression, relation pairs and relation groups respectively to describe location relation of drawing blocks, alignment relation of drawing blocks and zoom relation of drawing blocks, an analysis model of drawing layout is presented. This model also takes variation of drawing layout area and relation between title bar and other drawing blocks into account. Optimization procedure is divided into two steps: firstly, an optimum combination, which satisfies all restrictions and could make the useable area of drawing blocks as large as possible is obtained; secondly, spaces among blocks could be optimized in both height and width directions to make distribution of drawing blocks on drawing as even as possible. On the precondition that each drawing block has three or less optional ratios, optimum layout effect is achieved in acceptable time. Layout test indicates that this algorithm is reliable, effective and its result is reasonable and could fulfill requirements of commercial applications.