Advanced Engineering Forum Vols. 2-3

Abstract: This research aims at the vibration control of vehicle seat suspension system. A three degree of freedom quarter vehicle model is used for semi-active control system in which a magnetorheological damper (MRD) is installed at the position between the vehicle body and the seat. A fully active linear quadratic regulator (LQR) control strategy is used to determine the optimized control force which is then matched by MRD to compute the semi-active control result. Computation result proves that semi-active control with MRD can alleviate the vehicle seat acceleration to improve ride comfort.

Abstract: Combinatorial technology is a powerful tool for new material exploration. La_1-xCa_xVO₃ composition-spread films were fabricated by combinatorial pulsed laser deposition and their thermoelectric properties were evaluated paralelly by the multi-channel thermoelectric measurement system. Concurrent X-ray analysis verified the formation of solid soluted films in the full composition range (0≤x≤1) as judged from the linear variation of the lattice constants. Growth conditions of LaVO₃ films were optimized. Good crystallinity of LaVO₃ film was obtained at 800°C, and the power factor of 0.6 µW/cm K² was achieved. The effects of oxygen content and the substitutions of Ca and Ce ions on TE properties of were also analysed respectively. Large TE properties in vanadium oxide system can be expected with the change of vanadium ion valence from 3+ to 2+. In La1-xCexVO3(0≤x≤1) system, Ce ion takes 3+ although Ce⁴⁺ is stable in theory.

Abstract: Magneto-rheological (MR) fluid mount demonstrates excellent performance of vibration isolation in a wide frequency range and potential application in engineering. In this paper, a new mixed mode MR mount is proposed and an analytical model is established and used to predict the performance of MR mount. Meantime, a six degrees of freedom dynamic model of an in-line four-cylinder engine which has three points mounting system is derived by considering the dynamic behaviors of MR mount and its state space form is established. LQR and fuzzy-logic controllers are designed and synthesized to actively control the imposed vibration. The simulation results show that the proposed LQR or fuzzy-logic controllers can isolate the vibration of vehicle engine in a wide frequency range. The amplitudes can be suppressed well by employing this mount system. Its effectiveness will be verified via experiment in the second part of this work.

Abstract: A new type of multi-site magnetron sputtering system has been researched, which has more than one workbench. Based on the operating principle of the magnetron sputtering system which with a circular plane target, a mathematical model has been developed to simulate and discuss the influencing factors on the film thickness uniformity. The results showed that when the substrates were rotating axially and eccentrically, the film thickness distribution were affected by both the target-substrate distance and the eccentricity. If the eccentricity was constant, the film thickness would become thinner when the target-substrate distance increased, and the thickness uniformity tended to be improved. If the target-substrate distance was constant, the thickness uniformity would become better when the eccentricity increased. Moreover, if the substrate rotated axially and revolved around the target simultaneously, the thickness uniformity would become better when velocity ratio of axial rotation to revolution increased. And the effect of the thickness uniformity became small gradually if the ratio increases to a certain degree. In addition, increasing the etching area properly not only could conduct the film distribution to better, and improve the substrate film thickness uniformity also. Finally, taking a series of experiments, and analyzing the experimental data, the conclusion of the study results in the paper had been verified.

Abstract: In order to solve the traditional problems such as long designing cycle and high designing cost, the research applies the virtual simulation technology to the design of cathode target on magnetron sputtering vacuum coater. Through analyzing, modeling and simulating, the process model of a typical cathode target on magnetron sputtering coater is proposed. The virtual design of cathode target framework based on distributed collaborative simulation is constructed, which provides a theorial basis for the research of virtual design on cathode target.Using Solidworks software, parts modeling and assembly modeling of cathode target are realized. Using ADAMS, the movements of charged particles in magnetic field and high frequency alternating electric field are simulated, and the visual animation simulation of particles movement is achieved. The research demonstrates the feasibility of virtual simulation technology on vacuum coater design.

Abstract: An idea of self-helpingly exchanging and charging batteries is proposed to solve some Battery Exchanging and Charging (BEC, for short) problems of Electric-Networked Vehicles (short for, EN-V). Large scale BEC stations occupy large working area and need high equipment cost; common charge piles have disadvantages of long charging time. As a result, a physical demonstration system, which encompasses intelligent vehicle system, BEC stake system and GPS (Global Positioning System) simulation system, is established to validate the feasibility of the idea.

Abstract: This paper proposes an improvement method of zero suspension force performance using a special permanent magnet for a magnetic suspension device. The zero suspension force of a permanent magnetic suspension device is indispensable for floating off when the suspended object is stuck on accidentally. Generally, the magnetic suspension system using permanent magnet is difficult to realize the zero suspension force, since the permanent magnet cannot make its attractive force zero. However, the proposed magnetic suspension device has realized the semi-zero power suspension and semi-zero suspension force, which mainly consists of a disk-shape permanent magnet, two “F” shape iron cores, a suspended object, and an actuator. In the magnetic suspension device, since there is magnetic leakage, the suspension force could not be made exact zero. Therefore, in this paper, the zero suspension force will be improved using a special shape permanent magnet. The comparison results indicate that the zero suspension force is decreased about 80 percent.

Abstract: For the last several decades, many results have been presented for controlling nonlinear systems that have parameter uncertainty. In this paper, we propose an adaptive state feedback controller based on input-output feedback linearization for electromagnetic levitation system(EMS) with unknown ball mass. We analytically show the regulation of the controlled electromagnetic levitation system by the proposed adaptive state feedback controller. We show the experiment results of electromagnetic levitation system and where there is uncertain ball mass.