Applied Mechanics and Materials Vol. 389

Abstract: The paper build simulation model of MTU396 diesel generating sets through the SIMULINK, and then using MATLAB real-time workshop (RTW) to transfer the SIMULINK simulation model into a portable embedded c + + code, in the Visual c + + integrated development environment to develop semi physical simulation system of diesel rotational speed control . The method makes full use of the SIMULINK rich, convenient modeling environment, at the same time plays a powerful hardware control function of VC and the advantages of human-computer interface flexible design. This paper introduces the development of semi physical simulation system with the method of specific steps and realization method.

Abstract: This paper designs a three cascaded sigma-delta modulator with using mash structure. Analysis of gain coefficient of each module and simulate the modulator for the behavioral level. In 0.5μm CMOS process conditions, the input signal bandwidth is 20 kHz, oversampling rate is 256, SNR of the simulation model can get 100.5 dB, and accuracy is greater than 16 bit. Compared with other structures of the modulator, it has more stable and more dynamic range, so it can be applied to audio-frequency circuit.

Abstract: A high-gain folded cascode operational amplifier is presented. Structure of folded cascode operational amplifier and manual calculations are discussed in detail. Folded cascode structure for the input stage is adopted. Folded cascode structure can increase the gain and the value of PSRR. Folded cascode structure can also allow self-compensation at the output. The operational amplifier is designed in 0.35μm CMOS process with 5V power supply. The operational amplifier has high-gain and work steadily. The results of SPICE simulations are shown that the operational amplifier achieved dc gain of 110dB with unity-gain bandwidth of 74.3MHz and phase margin of 54.4 degree.

Abstract: One design method of small digital angle sensor based on microelectronic mechanical system (MEMS) is introduced. The angle sensor is build with the embedded microprocessor STM32F103 as the core. The acceleration value of MEMS accelerometer in X, Y, and Z-axis directions was used to calculate the angle of measured target on the horizontal direction and vertical direction, and the digital and miniaturization of digital angle sensor are realized.

Abstract: In order to further improve the performance of the air launched ballistic missile, a full range of air launched method had been given. For the full range launch program faced initial roll angle and initial lateral speed problem, researched the initial roll angle control mode processing technology in the virtual body coordinates and correct the lateral initial velocity method used angle of sideslip flight procedures. Given the ballistic flight simulation Using the proposed method and technology, and verified the feasibility of the ballistic missile program of all-round air launched.

Abstract: This paper takes a parallel mechanism of a loading test device, analyzes a degree of freedom of the parallel mechanism, builds a geological model in ADAMS software, applies restriction and load, and sets a performance function; this paper solves the problem of Jacobian matrix ambiguity of the parallel mechanism through releasing three kinematic pairs in ADAMS, transforms the solved angle to Euler angle of coordinate series of two parts through local coordinate system of ADAMS, simulates and solves the included angle movement scale between following ground jack 5 and dynamic and static platforms through the performance function of ADAMS, thereby providing accordance for the design of the loading test device.

Abstract: It has been analyzed the assembly of electromagnetic drive - inlet valve operating in camless valvetrain. The valve made of TiAl alloy has mated with its guide made of phosphor bronze. The scheme of electromagnetic valve drive has been shown in the article. The head aim of the motion control for such valve has been to provide small values of the valve velocity near the valve seat position. The aim of present analysis is to study the course of friction force between valve stem and its guide against time during use of control algorithm presented in the article. Curses of generated electrodynamical force against displacement of coil - valve assembly has been computed using FEM method and presented in the article. The courses of valve lift against time for different conditions have been presented in the article.

Abstract: Electro-thermal analysis of a new micro-hotplate designed for gas sensor has been studied in this paper. Through the comparison of materials, select pt as electrodes material, Si, SiO₂ as substrate materials. Then, through the optimization of substrate structure, in order to make the gas sensor obtain perfect properties of good temperature uniformity, the thickness of Si substrate, thermal insulation layers are 150, 50, 100 µm respectively. The new micro-hotplate structure is benefit for the improvement of sensitivity and overall performance of the sensor.

Abstract: The thesis presents a set of design scheme of grating displacement measuring system by taking SCM (Single Chip Microcomputer) as the core component. It describes the system design principle and the design process of software and hardware in details, i.e. realizing standard TTL level signal output through the processing of grating output signal amplification, sub-dividing, modulation and driving, so that grating output signal could match the numerical control system. It turns out that the designed grating displacement measuring system is able to satisfy the requirement of high-speed sampling and storage and feasible to be used for the measurement of actual grating displacement. The system has a simple and compact structure and a lower price, and owns favorable practical performance.

Abstract: In this paper, Using CSMC 0.5μm CMOS process to design each sub-module, the circuit simulation, and adjustment and validation of parameters have been carried out by simulation tools. The low static power and high conversion efficiency charge pump LED driver circuit has been designed. The circuits nucleus module is adaptive charge pump (1x/1.5x/2x charge pump), to converse a wider range of input voltage to a constant output voltage with high efficiency. This circuit only needs some external capacitors, and dont need inductor. So it reduces EMI electromagnetic interference and application cost, etc.