Applied Mechanics and Materials Vols. 155-156

Abstract: Analysing the wear characteristics and features of vertical shaft impact crusher in the use of the principles of Tribology. Obtain the wear types and mechanism. Summarizes the factors which impact wear and tear, life and reliability. By selecting appropriate material and structure to optimize two respects its anti-wear measures were studied. Put forward to solve the method of reducing the wear problem.

Abstract: At modern science and technology information-based society medium, at various athletics science in, according to living creature technical sport biomechanics technique at modern athletics technique in, for raise the athlete's performance at and sport technique, and excellent turn to exercise an equipments to develop an important function.Therefore, best sport analysis can provide the best sport carriage and sport technical ability, thus the training result of the exaltation athlete of science.The textual purpose is to run a technique according to the biomechanics research athletics, train the theory of providing science for the athlete's science basis, promote the development of athletics business thus.

Abstract: To study the path planning problem of multiple mobile robots in dynamic environments, an on-line centralized path planning algorithm is proposed. It is difficult to obtain real-time performance for path planning of multiple robots in dynamic environment. The harmonic potential field for multiple mobile robots is built by using the panel method known in fluid mechanics, which represents the outward normal velocity of each line of a polygonal obstacle as a function of the length of its characteristic line. The simulation results indicate that it is a simple, efficient and effective path planning algorithm for multiple mobile robots in the dynamic environments that the geometries and trajectories of obstacles are known in advance, and can achieve real-time performance.

Abstract: This paper main aim to explain the finite element analysis and experimental test on loading machine structure strength analysis method of finite element analysis, test data as the input and boundary conditions of finite element calculation model of collaborative test accuracy. The finite element analysis and calculation conditions of test conditions can be used as a supplement and perfection.

Abstract: In order to evaluate the vibration history of the engine block and predict its surface vibration status, a FEM model on 4102BZQ Diesel Engine block was constructed. Based on the cylinder pressure curve of 4102BZQ, some important exciting forces applied on the block were calculated. ANSYS software was used to compute and analyze dynamic response of the block. Simultaneously the node displacement history of the block model was obtained. The results of calculation and analysis showed that the vibration of the block skirts was more intense and the skirt was the main factor to influence the reliability of the engine. Cylinder head bolt force and piston slap force had significant effect on the top area of the block, and the surface vibration of the skirt was strongly influenced by the crank shaft load.

Abstract: It is known that two primary disadvantages of parallel manipulators are the complicated forward kinematics and limited workspace. This paper mainly addressed the kinematics and workspace analyses of a 3/3-RRRS 6-DOF parallel manipulator. After a brief introduction of the 3/3 -RRRS 6-DOF parallel manipulator, a three-dimensional model and its relevant structure diagram are constituted, the forward and inverse displacement analyses of the 3/3-RRRS parallel manipulator are discussed in detail, especially, a novel geometrical method referred as equivalent mechanism is proposed for the forward displacement analysis of the manipulator under consideration. Based on the displacement analyses of the manipulator, a discretization method is proposed for the computation of the reachable position/orientation workspace of the 3/3-RRRS parallel manipulator, respectively. Examples of a 3/3-RRRS parallel manipulator are given to demonstrate these theoretical results.

Abstract: Friction stir welding (FSW) is a new and promising welding process that can produce low-cost and high-quality joints of Al-Li alloy. In order to demonstrate the friction stir weldability of Al-Li alloy and determine optimum welding parameters, the effect of FSW welding parameters on the tensile properties of the Al-Li alloy butt joints has been studied in this paper. The results showed that, when the heat input increased, the ultimate strength and elongation of butt joints decreased. For the Al-Li alloy butt structure with the thickness of 2mm, the optimum parameters were the rotation speed of 600 rpm, the welding speed of 400mm/min, and the ultimate strength of butt structure was the maximum strength, arrived at 413MPa, equivalent to 83% that of the base material. Furthermore, it was found from the microstructural observation that, the welding parameters had obvious effect on the grain size of welded zone. As the heat input increasing, the grains of weld nugget and heat affected zone became larger accordingly. In addition, a special layered phenomenon appeared at tensile fracture surface, the tensile cracks initiated from the surface on welded zone near the thermomechanically affected zone(TMAZ) on the advancing side and then grew along the interface between the weld nugget and the TMAZ. The overall fracture mode was ductile - brittle hybrid fracture.

Abstract: The concept of clutch friction plate temperature acquisition system is proposed based on Zigbee wireless technology because the clutch is of high-speed rotation and is hard to be wired. The Zigbee module based on MC13213 is selected as the core unit. The hardware and software of clutch temperature acquisition system are designed. Finally the bench test is conducted, which verifies the feasibility and reliability of the design.

Abstract: The scattering of creep rupture data was represented by Z-parameter method based on Larson-Miller method. It was verified that the values of Z were supported by normal distribution. After obtained the distribution characteristics of creep rupture data using Z-parameter, reliability design for rupture allowable stress was carried out according to design life. Safety factor method is used for safety guarantee in conventional rupture allowable stress design and minimum rupture strength method is used in some standard. In comparison with safety factor method and minimum rupture strength method, it can be seen that reliability design based on Z-parameter is more agree with experimental data than other methods. Reliability design provides more precise results by considering the real distribution of creep rupture property and provides more flexible choice for design due to the need of safety and economy.

Abstract: Automatic vehicle is a very efficient way of material conveying in modern industry, control system design is the key part of automatic vehicle. To devise delivery vehicle control system using Single-chip Microcomputer, wireless communication technology, which was applied to traditional Chinese Medicine pills packaging workshop. To study control system overall project, hardware design and software design including the main program, wireless communication module etc.To achieve automatic delivery in the Chinese Medicine pills production line.