Advanced Materials Research Vols. 875-877

Abstract: Horizontal casting machine is one of the key equipments of the continuous casting production line for aluminum ingot, the stable running of transporting chain has direct effects on the surface roughness of the finished aluminum ingots and the technical data of the machine. The casting machine supports are the main carriers of molds,the drive chain and other components,which have long-term work in hot and humid environment and easily leads to the running stationarity of transporting chain reduced. So in order to improve the operation stability of the transporting chains of the casting machine and the surface roughness of the finished aluminum ingots, the sequential coupling analysis methods of thermal structural coupled analysis module of the finite element software ANYSYS is used to analysis of thermal deformation and temperature field simulation for the casting machine supports, and determine the size and distribution pattern of the thermal deformation and thermal stress of the casting machine bearing parts,the simulation results provide a theoretical basis for new product design and development work in the selection ,structure and layout optimization.

Abstract: Welding process with trailing heat sink for 2 mm mild steel plates has been analyzed to estimate distortion and residual stresses using a finite element modeling software Sysweld. The material properties used for the analysis are both temperature dependent and phase dependent. A transient thermal analysis is carried out using Goldak double ellipsoidal heat source model and heat sink as Gaussian model with negative heat flux. The finite element analysis (FEA) is conducted by considering the material properties of all phases of steel as well as without phase transformation i.e. by considering properties of only ferrite phase. Temperature distribution, distortion and residual stresses are calculated and compared for four cases: without phase without cooling, without phase with cooling, with phase without cooling and with phase with cooling. It is found that FEA without phase transformation effects overestimates the residual stresses in the fusion zone (FZ) and heat affected zone (HAZ). It is also found that a trailing heat sink reduces transverse compressive residual stresses thus minimizing the possibilities of buckling.

Abstract: An Instrument for measuring torque and shear modulus based on flat coil element for material research has been developed. Flat coil element was made from a thin epoxy with number of coils 30 and outer diameter of 3 cm. Working principle of the sensor is based on position change of a disturb element which attached to test shaft in front of the flat coil. The change of position will change the total inductance of the sensor system. The change of inductance is measured using LC oscillator by measuring its resonant frequency. An F/V converter converts the resonance frequency into voltage. The flat coil is used to measure the change of angle of the developed torque instrument. Using microcontroller ATMEGA16 the developed instrument can be controlled and work automatically. The developed instrument can measure torque and shear modulus with relative error less than 3%

Abstract: With the continuous improvement of voice technology and the rapid development of Single-chip Microcomputer technology, voice recognition robots emerged. In this paper, a voice recognition robot was designed and Implemented by combining of toy robot and a microcontroller SPCE061A with some transformation. It can be controlled by trainers voice to walk forward, backwards, turn left, turn right, dancing with the music, left or right to aim, launch and continuous emission and other interesting action. This work is valuable to education teaching and research.

Abstract: An ultra-high-speed and high-accuracy charge-coupled device (CCD) laser displacement sensor is used to track and measure the ultrasonic vibration in real time. A series of Matlab programs are developed to filter noise from original data. The ultrasonic vibration frequency and period are evaluated and the ultrasonic amplitude is measured within accuracy ±0.1 μm. Effect of the ultrasonic power on the ultrasonic amplitude is also studied.

Abstract: The performance of acoustic image measurement technique will be affected badly by coherence interference, even unable to get the noise targets image at all. A null weight constrained by zero and first derivative based on focused beam forming is proposed in this paper. The weight can put null on the given positions which are only decided by the interferences positions. The weight also has advantages in high robustness and low computation account which doesnt have to be calculated on real time. Simulations about single and multiple interferences on the condition of different SIR are proposed in the paper. And the results show that the new weight proposed in this paper can get targets image while putting nulls on the coherent interferences position.

Abstract: It establishes the model of hydraulic driving quadruped walking robot by Lagranges equation according to mechanism parameter. It determines the relationship between joint space and operating space. Comprehensive using the software Pro/E and ADAMDS, then build its virtual model and present dynamics simulation. It analyses the robots walking tracks and stability of motion. It provides theory reference for optimized out reasonable quadruped walking robots structure parameter.

Abstract: The mechanical ventilation system of new type underground granary was designed and three wind pipe models with different length were investigated in this paper. Dynamic numerical simulation was applied for evaluating the cooling effect of mechanical ventilation of the granary. The simulation results, including temperature field, flow field and pressure field results, show that the cone shaped base of grain granary is better than flat shaped base. It is an optimal project that the main wind pipe opens with mesh only in the bottom. In addition, four vertical guide plates were set up around the main wind pipe, which have the function of saving energy and reducing consumption.

Abstract: High-performance filter is the key to improving the detection accuracy of geophysical instruments. In order to achieve high-precision measurement of small signals, this paper presents a design of high-performance programmable filter based on TLC7528. The system design mainly included programmable amplifier circuit design, programmable filter circuit design, amplitude-frequency test circuit design, display circuit and the keyboard circuit design. The system used a microcontroller as the control center for system parameters setting and control, adopted analog switches and selected low-noise op amp to achieve programmable gain control, used TLC7528 to realize the filter cut off frequency adjustable by changing its internal resistance value and used the DDS chip and RMS conversion chip to design the circuit of amplitude-frequency characteristics, so as to test and analysis the signal amplitude and frequency of the system design filter. The experimental test data showed that the high performance filter has the characteristics of good linear, small voltage gain error, low power, flexibility and little environmental impact. It can significantly improve the accuracy of the geophysical detection equipment.

Abstract: Multiple 1090ES ADS-B signals may be overlapped in the receiver systems on the ground. At the same time, 1090ES ADS-B signals may be interfered by A/C replies with the same carrier frequency. To address these problems, firstly, principle component analysis (PCA) is employed to pre-whiten the observed signals in order to reduce the relevance between signals. Then extended projection algorithm (EPA) is applied to separate 1090ES ADS-B signals. Effect of the separated signal is verified by simulation. The performance of this algorithm is also analyzed in several aspects. Simulation results show that this algorithm not only can succeed in separating multiple 1090ES ADS-B signals effectively but also has both higher precision and strong ability of stability.