Applied Mechanics and Materials Vol. 160

Abstract: This paper discusses the reduction algorithms of a multi-covering decision system. Firstly, we give the belief structure in a covering system and give a rule of information fusion of multi-covering information. Then, we introduce special conditional entropy of a covering decision system with multi-coverings by the fused mass function and study the reduction of multi-covering information by means of limited conditional entropy and consistent multi-covering decision systems by means of conditional entropy. Two algorithms are designed to compute reductions of a multi-covering system and a consistent covering decision system, respectively.

Abstract: Rapid prototyping (RP) is an advanced manufacturing technology and has obtained widely application in recent years. RP technology can be used to machine complex physical part directly from CAD data without any cutter or technical equipments. A variety of new rapid manufacturing technologies have emerged and developed include Stereo Lithography (SL), Selective Laser Sintering (SLS), Fused Deposition Modeling (FDM), Laminated Object Manufacturing (LOM), and Three Dimensional Printing (3-D Printing). The paper summaries the working principle and discusses the application fields for four typical rapid prototyping technologies. Finally, the significant performance of rapid prototyping for modern industry is discussed. The investigation is beneficial for choosing an optimal forming process in industry.

Abstract: The Hydromechatronics model of Crane is built by Proe/Adams/Matlab, and then the movement and force of the drive oil cylinder is analyzed, also the improvement of hydraulics and control system is simulated. The simulation method and result give some data for the design of Crane.

Abstract: We present a comparative study on band-gap structures of Lamb waves propagating in one-dimensional quasi-periodic composite thin plates, which are composed of different quasi-periodic models such as Cantor, Fibonacci, Thue-Morse, and Double periodic sequences, respectively. The transmitted power spectra (TPS) of the transient Lamb waves propagating in composite plates is calculated numerically by employing the finite element method. By comparing among TPS in different plates with the different ratios of the plate thickness to the lattice spacing, it is found that different quasi-periodic models present different behavior of the split-up of band gaps. Our works are significant not only for understanding intrinsic physical property of the quasi-periodic sequences, but also for designing the special structures of quasi-periodic arrays to adjust the width of band gaps and the frequency ranges of phononic crystals in applications.

Abstract: Based on algorithms of artificial potential field and inertial navigation positioning, the design and implementation of robot is introduced with the features of obstacle avoidance and navigation automatically. Experiments show that the robot can navigate to destination effectively without any collision.

Abstract: With the development of modern high technology, the request of exploring material of the request has been a high demand for researchers. Along with the understanding of microscopic structure and macro structure for material property, people have can theoretically predicted with special structure and function of the material system, thus designed more to meet the requirements of new material. In the rapid development of the computer technology today, the computer simulation has become an efficiency tool for solving practical problems in materials science. This paper has detailed described the basic principle of computer simulation and then provide an example to show the research work flow of computer simulation. This example can calculate the shear and bending moment of beam under simple load condition. The research contribute to apply the simulation method in material science.

Abstract: When researching on a global feasible products solutions, we need to consider the product of manipulation, practical, environmental protection, social demanding performances and so on. The several life cycles of a product determines and implements these performances.And the several cycles are mutual correlation, mutual restrict.Every link is crucial, so we must coordinate the relationship among them. The purpose of this paper is to simulate and solve the problem of life cycle by using different, restrictive,and satisfactory method.

Abstract: A system at inception is endowed with a random amount of resource, the process of the lapse of system life can be viewed as that of the depletion of random resource caused by the wear-out effect. This thesis considers the wear-out process of the system as the sum of an additive compound nonhomogeneous poisson shock wear-out and a continuous routine wear-out in time t. With the introduction of the concept of random resource, a wear-out model is built. Moreover, the aging properties of the system lifetime are studied in this model.

Abstract: A simply analytic model is developed base on wrinkle geometry model. The three concentric circles are adopted to represent top coat, oxide coat and bond coat of thermal barrier coating, and then shakedown analysis is established based on the model. A numerical model has been given base on wrinkle geometry model in a thermal barrier coating system, and the model on static shakedown analysis is developed by finite element method. Shakedown limit of thermal barrier coating is calculated for various undulation shape and thermal grown oxide. The simply analytic results and numerical results are approximate for undulation shape is not very irregular. The simply analytic model is convenient for calculating shakedown limit of thermal barrier coating.

Abstract: Tool cutting envelope (TCE) and tool path (TP) for planar profile machining are calculated at the same time in the presented work, using a novel motion method called Rolling Disk Motion (RDM) method. RDM method employs a rolling disk (RD) as the manufacturing tool, and considers the disk running around profile boundaries as cutting process. During this RD motion, RD center locus is just TP for profile or contour-parallel manufacturing strategy. Also, the track of point on RD contracting with the profile is just TCE. Furthermore, the RDM technique can find a further application in the study for uncut areas in machining domains. As well, the calculation of TCE, TP and uncut areas, based on RDM, are finished only by simple point transformations and arcs creation. Finally, an example is included to illustrate TCE and TP computation by means of RDM, and the result shows that the approach is implemented and tested successfully on real-world data.