Applied Mechanics and Materials Vol. 454

Abstract: In this paper, based on the principle of exponential approach law, an integral sliding mode controller (ISMC) for brushless doubly-fed machine (BDFM) adjustable speed system is presented. Because of using the integral sliding mode control, the proposed controller for BDFM employs the robustness and excellent dynamic performances of ISMC. Simulation results show that the proposed control strategy is of the feasibility, correctness and effectiveness.

Abstract: The measurement principle of furnace temperature field based on flame radiation image is analysed, nonlinear optimization mathematical model aiming at measurement objects is established, a temperature field measurement algorithm based on BP neural network is put forward. It can draw the furnace temperature field distribution by constructing the BP neural network, inputting image sample, outputting temperature sample and choosing appropriate sample training network. In the end, the measurement accuracy can be effectively improved and there is sure to be a good application prospect.

Abstract: This paper analyzed the influence that divided conductor to electrical fast transient burst. Divided conductor may change the magnetic field distribution around the conductor, but accordingly increased conductors electrical susceptance. The mechanism that the disconnecting switch cut off the power line when the no-load current is at peak and electric arc distinguished when the current pass zero and accordingly restraining measure is proposed. The outcome showed that the model can simulate the electrical fast transient burst in capacitive power line and makes it easy to analysis complex power system problems based on simple model. The method is proved to be correct and enforceable by validation of protective measures.

Abstract: It's a type of wheeled robot based on the AT89S52 MCU, through the body and infrared emission source docking judgment target position, the differential signal to control the motor speed to improve the direction; used ultrasonic obstacle avoidance module continuously detect the front object distance; used the error compensation principle of probability and statistics on the mechanical arm debugging and correcting, so that the system may realize to the target automatically crawl.

Abstract: In view of well- designed showing platform is advantageous to promoting exhibition effect, the author analyzes the developing course of showing platform, and combining the mechanical design problem of existing showing platform which exists in using function, art function and material technique function and others, discusses the mechanical design requirement, the fundamental structure and working principle, the shape design and the color design of showing platform of rotation and vertical reciprocation. Among them the fundamental structure and working principle mainly elaborate the constituent parts of showing platform, the structure characteristics and working manner. Then the possibility is analyzed. On this foundation, the practical application of showing platform of rotation and vertical reciprocation is analyzed.

Abstract: The mechanical engineering for flight are important for flight safety to prevent the flight accident, improve the management and decision-making level of flight safety. In order to improve the safety of flight system, a flight safety evaluation method based on relevance vector machine and flight mechanical engineering is proposed. First, based on system viewpoint, according to the actual situation of flight safety, the factors that influence the safety of flight system are found out on four sides of human, flight mechanical engineering, environment and management and the flight safety evaluation index system is constructed; then the flight safety evaluation model based on relevance vector machine developed in the framework of Bayesian theory is briefly introduced; finally using the index system the relevance vector machine evaluation model of flight safety is establish. The actual example confirms its feasibility.

Abstract: A collision detection algorithm based on hybrid bounding volume hierarchy was proposed using k-DOPs and sphere between complex objects. A simple algorithm to the particular structure of hydraulic servo manipulator was introduced based on the relation of line to line and line to plane to deal with real time collision detection between graphicrobot and operation task in consideration of the bounding volume hierarchy method.Validity of thisalgorithm was proved through experiments . The experimental results show that the proposed collision detection model is simple and fast in calculation,and easy for realization.it can solve on line simulation problem in remote operation for construction robot,and could be applied in simple virtual reality system.

Abstract: The intermediate link of nc systems and machine tools is Servo system. Servo system failure is an important part of the failure of CNC machine tools. Firstly, most common servo system fault mode is introduced from actual work; Secondly, according to fault locating method to determine fault location is discussed; Finally, servo system fault diagnosis example and processing method are introduced.

Abstract: The paper introduced image processing technology based on image segmentation about on-line threads images, and describes in detail image processing technology from mage preprocessing, image gmentation, and threaded parameter test. Threaded images of on-line processing parts obtained are introduced as the key technology, Target edge extraction process from the segmented image are also recounted. At last, this article shows a comparison between actual machining parameters of screw thread and the standard parameter , provides the criterion for error compensation.

Abstract: A MEMS Microneedle Array was modeled, designed and simulated. The mechanical properties of the microneedle structure were theoretically analyzed including analysis of fracture strength and distribution of von mises stress. The conditions of initial insertion and after initial insertion were considered. The detail linear and nonlinear buckling analyses on needle structure were also presented. Two modes of buckling were come to and discussed. The fabrication of microneedle array was simulated by employing Intellisuate and bi-mask technique. The microneedle array can be used in microsystem for in-vivo fluid sampling and drug delivery.