Abstract: The parallel kinematic machines have broad application prospects in the manufacturing industry. Good dynamic characteristics are needed for the structure, which has direct influence on working efficiency, stability and reliability. ANSYS software analysis of their dynamic characteristics is accurate and easy, and can quickly modify the design fault and reduce design cost. In this paper Pro/Engineer is used to draw the solid model of PKM and assembly each part to constitute a system. At last the whole system is imported into ANSYS. The finite element model is established with the simplified model and element equivalent simulation, and modal analysis is conducted using model vibration theory and finite element theory. After the vibration deformation analysis of whole system, the weak parts, i.e. each bearing joint and the power transmission chains, are identified. The weak parts can then be enforced to improve the dynamic characteristics of the whole system.
Abstract: In order to investigate the effect on manufacturing quality of focus position misalignment between laser beam and powder convergence in laser metal deposition shaping (LMDS) processing, several experiments including single-track monolayer, straight thin-wall and ring thin-wall were made. The measurements and analysis on shape, size and surface quality of the experiment parts were carried out. An omnidirectional detecting method to check the misalignment of focus position was brought forward and tested. The results indicate that the misalignment of focus position directly affects the quality of shaping parts and shows the regularity, the detecting method can easily detect the focus position misalignment on random direction and angle and guide the adjustment on them.
Abstract: Storage management is the core of the material management. The design rules of storage management system are presented as such that the usability, reliability, progress, openness, data integrality and unity, and security must be ensured. Demand analysis is performed for the storage management system of Huachen Xinguang Engine Plant. The functions and the corresponding subsystems are scheduled. The configurations of data flow in supply management, stored. It took positive effect on raising the productivity.
Abstract: Assembly sequence planning (ASP) is the foundation of the assembly planning which plays a key role in the whole product life cycle. Although the ASP problem has been tackled via a variety of optimization techniques, the particle swarm optimization (PSO) algorithm is scarcely used. This paper presents a PSO algorithm to solve ASP problem. Unlike generic versions of particle swarm optimization, the algorithm redefines the particle's position and velocity, and operation of updating particle positions. In order to overcome the problem of premature convergence, a new study mechanism is adopted. The geometrical constraints, assembly stability and the changing times of assembly directions are used as the criteria for the fitness function. To validate the performance of the proposed algorithm, a 29-component product is tested by this algorithm. The experimental results indicate that the algorithm proposed in this paper is effective for the ASP.
Abstract: A new approach that combines neural network and 0-1 programming was proposed. Based on the lifecycle analysis, the characteristics of new products can be divided into four categories with different benefit curves and parameters. A neural network is used to classify the new product and the 0-1 programming model is then developed and used to determine what products to be introduced into marketplace. Numerical example is given finally to show that this model is effective for firms.
Abstract: Further research on the target locating technology and system exploitation based on the GPS technology is made in this paper, and the locating model based on the GPS technology and the orientation terminal posture gaining model as well as its algorithm based on digital compass are established. On this basis, this paper puts forward a solution to the target locating measurement and controlling system based on GPS and digital compass. The system adopts the structure of the host computer and the client computer: the client computer is the hardware realization of target locating system and also can be operated separately; the host computer monitors the client computer remotely. The system can directly get posture information, with advantages of simple structure, upstanding stability, low price and so on, and can satisfy the function of locating system. The client computer passed through the high and low temperature test, resistance vibration test, electromagnetic compatibility test and so on. In the functional testing, the automatic alignment precision of the system attains to and manual alignment precision attains to , completely match the practical requirements.
Abstract: Theoretical analysis of existing evaluation method of gap roundness error and existing evaluation model of full roundness error is provided. Mathematical model of gap roundness error’s evaluation with least square method is founded based on the evaluation model of full roundness error, which gives a solution of gap roundness error. The results of the simulation analysis and measuring experiment show that mathematical model of gap roundness error’s evaluation with least square method is correct for computing gap roundness error.
Abstract: As an important forged part of an automobile, the inner hole of the half-shaft bushing must be formed directly. However, the process requires many steps, and how the forging, or deformation, is spread over the production steps directly affects the die life and forging force required. In this paper, the three steps involved in directly forging a half shaft bushing's inner hole are simulated using the two-dimensional finite element method. Further more, we improve the forging process. From numerical calculation, the improved necessary forging force is found to be only half the original force, and the die life is doubled.
Abstract: Following spatial mesh principle, the gear cutting meshing equation was established in the paper through analyzing the relation between the machining principle of the double circular arc profile spiral bevel gear and the movement of the machine tool. The parameters of cutter head and the machine tool’s movement were then obtained through the equation. VERICUT was applied to build the three-dimensional virtual simulation machining model by which the gear geometry parameters, cutter parameters and machining tool movement parameters were calculated for a given gear to be processed and virtual simulation machining proceeded to prove the validity of the model.
Abstract: Metal- matrix composites layers were prepared by laser cladding with Ni-based Super-alloy onto CrMo cast iron. Applying uniform experiment design, under conditions of different velocity and load ,the wear tests of alloy layers were carried out and the stepwise regression method are used to establish the wear rate model for prediction of wear rate. It is proved that the modal is significant and represents the character of the wear trend. According to the wear rate model ,the wear characteristics are analysed and the wear mechanisms are identified. The main wear mechanism of laser cladding layer are delamination, adhesive wear and abrasive wear.