Applied Mechanics and Materials Vol. 274

Abstract: In this paper, finite element analysis was used to study the whole stiffness on the Longmen type frame by Pro/MECHANICA, the model simplification and mesh principle were elaborated, as well as the advantage of Pro/MECHANICA with adaptive P-method technology and with the traditional finite element software with non-adaptive H-method technology. The weakest link of the whole stiffness on the Longmen type frame was found out. The three main factors of affecting the whole stiffness was put forward to.

Abstract: Marine gas turbine generator set; Flywheel energy; Stability Abstract. Based on modular modeling idea, the modular model of marine generation system was set by the technology of systematic simulation. One set of simulation models of marine gas turbine generation system was generated. Results show that flywheel energy storage device can enhance the stability of power grid and play a better role in making marine gas turbine generation system stable under heavy load fluctuations.

Abstract: With the development of human space exploration activities, the structures of many spacecrafts tend to be large. Due to the limitation of payload envelope size in the launch vehicles, large space structures must be folded in a limited space, and stretch to the desired configuration after reaching their orbits. Large space structures can be basically classified as assembling structures, expansive structures and deployable structures. Deployable structures are the most widely used, and the rod-shaped space stretching arms are the most widely applied one-dimensional space deployment mechanism. Currently, there are mainly three forms of rod-shaped space stretching arms are used in the field of aerospace: Storable Tubular Extendable Member[1,2], Coilable Mast[3], and hinged-rod stretching arm[4,5]. Hinged-rod stretching arm now becomes the studying focus of rod-shaped deployment mechanism for its precise positioning due to high strength and stiffness and characteristics that is in line with the large-scale spatial structure. The designs of a one-dimensional cable-rod deployment mechanism which is cable-driven based on the contrast of working principle and working characteristics of existing rod-shaped space deployment mechanism, and also some research was studied on its working principle and key technologies.

Abstract: Noises in the imaging process will result in image measurement errors, so whether these noises can be effectively suppressed is the key to improve the measurement accuracy. This paper analyzes the noise components of TDI-CCD system from three perspectives, builds the mathematical model of typical noises, designs correlated double sampling noise processing circuit for TDI-CCD system, realizes the software implementation of hardware design and achieves the purpose to improve the signal-to-noise ratio and image quality

Abstract: The structure of ejector used in automotive power steering oil discharge equipment is designed in accordance with the theory of gas-liquid ejector.The two important parameters of the ejector are elected respectively to five values and then 25 ejector models are obtained by the permutations and combinations.The ejector’s CFD model is created by Fluent module of Ansys,then it is divided into a grid and analyzed. Analyse its pressure distribution and velocity vector, which provides the optimal size for the manufacture of the ejectors and a theoretical basis for experiment.

Abstract: Taking multi-oil-cavity and multi-oil-pad hydrostatic bearings as studied projects, firstly make brief instructions for structure characteristics and working principal of hydraulic system; Then, build three-dimensional models of multi-oil-cavity and multi-oil-pad hydrostatic bearings respectively. Adopting finite volume method, oil film mesh is generated by universal finite analysis software CFD; then, carry on numerical simulations for pressure distribution and temperature distribution of the two studied hydrostatic thrust bearing under various viscosity, and make comparative analysis for difference between the two studied hydrostatic thrust bearing. Based on the analysis of numerical simulation results, the conclusions whether oil-return groove is set for hydrostatic bearing could be received. Simulation results reveal truly the influence of setting oil-return groove or not on hydrostatic thrust bearing, and improve structure design for hydrostatic thrust bearing.

Abstract: In the context of the session of the freescale Intelligence Car Competition, this paper designed the intelligent vehicle system based on MC9S12XS128 microcontroller and its mechanical system considering the driving-stability and comfort of car module. In the system, CCD camera gathers real-time track road conditions information, and then the microcontroller will identify road situation and realize tracking control with these information. Using time-optimal to control the DC motor speed and the positional PID to control the steering gear, adjust PID parameters dynamically based on the position of the black line. These measures guarantee the intelligent vehicle travel along a specified route safely、smoothly and fast, and then realize automatic tracing. The results show that the system meets the need of path recognition and anti-interfere well.

Abstract: To avoid safety hazards in the mine electric locomotive transporting, designed an anti-collision warning system for electric locomotive. The system took MCU AT89C52 as core controller, including ranging module, speed measuring module, display module, warning module and anti-interference design. The system used ultrasonic sensor and incremental rotary encoder respectively to measure distance and velocity, and then obtained the distance and velocity data through MCU AT89C52. Through analyzing these data, the system can alarm and stop the locomotive, and then ensure the safety of locomotive and workers. Therefore, the system has a very good market prospect.

Abstract: The design introduces fuzzy control logic to improve the static and dynamic performance of permanent magnet linear synchronous motor direct thrust control system and carries out reasonable fuzzy classification to the three variables of flux linkage error of primary promoter, electromagnetic thrust output error and flux linkage angle in combination with human control experience to improve the system performance and enable good robustness.

Abstract: A wind-driven feeding mechanism of high efficiency is designed according to the TRIZ theory and its mechanical structure innovative design based on the principle of energy conversion. It aims at delivering of small granular, cylindrical, flakes and other materials in machinery, pharmaceuticals, electronics and other industries by transmission mechanism such as the typical gear mechanism and linkage mechanism. The prototype is produced combined with the specific parameters of the common materials. The modular innovative design is adopted, including the transmission module, driver module and material feeding module. By the inspection of the actual operation, each design module of the produced prototype is stable and reliable. At the same time the effect of material transportation is good.