Applied Mechanics and Materials Vols. 157-158

Abstract: This paper uses the more intuitive visual processing of the camera to extract navigation information instead of using the low-end information collection technology of the photoelectric sensor as the current autonomous lawnmower navigation sensor. Image grey processing, binary algorithm, the image smooth method, the image inflation, the improved Hough transform combining with VC++ are used to get the line in order to distinguish the done and undone lawn successfully and to obtain navigation path and navigation parameters. The improved grayscale algorithm and the Hough transform algorithm have reduced the amount of image data processing, solved the small angle lines problem, and improved the real-time of the robots. Meanwhile prove the impossibility of image sharpening and border detection on extracting lawn boundary. The feasibility of the lawn image processing has been proved by examples.

Abstract: This article starting from the real engineering, have a deep search on permanent magnet synchronous motor servo system, analyzed the main research focus on permanent magnet synchronous motor control, focused on the mathematical model of permanent magnet synchronous motor, made some meaningful results. Basing on modular design principles, this article have a deep application research on design of permanent magnet synchronous motor DSP conducted, proposed DPS design, has a detailed analysis of permanent magnet synchronous motor servo system software design.

Abstract: Because of the excellent mechanical properties of Austempered Ductile Iron (ADI), track rollers can be made out of this material. The casting may lead to cracks forming inside rollers and there will also be some scratches in the surface when rollers work, which will greatly affect the lifespan of rollers. It is helpful to use crack propagation method based on the Finite Element Method (FEM) to simulate the crack growth. Firstly, define the position and the value of the force imposed on rollers. If the load is compressive, contact pairs should be set between the crack surfaces. After the model is established, Stress Intensity Factors (SIF) KI and KII can be calculated with the node displacement theory by using the commands of FEM software. With the maximum principal stress theory, crack growth direction can be determined. Since the values of KI and KII calculated by the software are positive, we should judge weather the values are positive or negative to get a right propagating angle. The analysis applies linear elastic fracture mechanics and FEM modeling the crack propagation in the elastic state.

Abstract: People recognized the importance of communication from Wenchuan earthquake in 2008, which could help rescue team to protect the life and property of the people without delay, at the same time reduce the loss caused by earthquake. According to the feature of emergence rescue in earthquake and requirement on communication of fire army, this paper set forth the application standards and modes of wireless communicating technology in the scene of earthquake rescue, which included wireless short-wave and satellite communication.

Abstract: This paper introduces a specific object-oriented, feature-rich four-axis automatic winding machine control system. It analyzes the structure, control requirements and motion regulation of the winding machine. It builds the mathematical model of the servo motor and the system, builds the experimental platform. Multiple sets of experimental data and curves are obtained after several experiments. The control system for winding machine, is reliability, and can greatly improve production efficiency.

Abstract: The 3D models created by the CAD software have different internal formats, which leads to the poor software compatibility. It takes much longer time while loading 3D models containing much more information by CATIA and so on. During the digital collaboration process of the product design, the quickly transmission of the 3D models is the indispensable part. However, the storage space occupied by 3D models of a large document, resulting in a longer transmission time, thereby will reduce the real-time performance of the collaborative process. A good solution in the industry is to use the lightweight format in product collaborative design. Nowadays there are a variety of lightweight formats. This paper focus on the comparisons of three lightweight formats(3D XML、JT、U3D) often used in the industry. Some experiments are given to evaluate the format effectiveness. In the end, the trend of lightweight formats is also predicted.

Abstract: In this paper, a multi-LAVs’ aerial delivery areas-choosing method is brought forward, which aims at known targets which are located in a fixed area. This method takes the performance of LAV, especially minimum turning radius, into consideration, and incorporates AHP and Dubins’ path. Based on the discussion of general GA method, we design the IGA method to increase the convergence rate. By using this method, the LAVs can reach the target located at the longest distance within the minimum time. Simulation results show that the IGA method has a higher convergence rate than the general GA method, while the delivery areas can be chosen in an optimized way. The proposed method can be extended to the problem of multi-Dubins vehicles’ task assignment and path planning.

Abstract: iEELab((Internet-based Electrical Engineering Lab) at Zhejiang University is an integrated laboratory including physical and virtual remote experiments. This paper first makes a brief introduction to the overall architecture of iEELab. Then, focusing on the virtual remote laboratory which uses a unified object-oriented language Modelica for modeling and simulation, we elaborate its architecture and the internal mechanism of virtual remote lab operation. Finally, taking a subsystem of iEELab-the plate angle control experiment system as an instance of the virtual remote lab, we display the process of modeling and simulation of virtual experiments using modelica.

Abstract: A dynamic model of automobile active suspension system is established, based on which a high dimension objective model for active suspension system is set up. And through linear combinations, high dimension multi-objective function is translated into a low dimension objective function. The modified NSGAII with single point compound crossover has been adopted to realize the optimization. In the paper, the performance active suspension system can realize integrated optimization. The results show that this way can effectively enhance effect of the automobile active suspension system.

Abstract: An experimental and analytical study on ultimate tensile strength of composite double-lap joints with different adhesive thicknesses is employed in the paper，test results indicate the major failure mode of joints is adhesive shear failure and the ultimate strength of joints increasing with thicker adhesive. Analytical model is developed to investigate the adhesive failure of double-lap joint based on the experiments. The model takes into account anisotropy of each ply in the composite laminates and elastic-perfectly plastic behavior of the adhesive in the joints. The validity of analytical model for calculating shear strain/stress distribution is certified by comparing with finite model results. Maximum shear strain criterion is adopted in the analytical model to predict the ultimate tensile load of double-lap joint. Good agreement of the analytical predictions with the experimental results is obtained.