Applied Mechanics and Materials Vols. 55-57

Abstract: Humanoid robot is not only expected to walk stably, but also is required to perform manipulation tasks autonomously in our work and living environment. This paper discusses the visual perception and the object manipulation based on visual servoing of a humanoid robot, an active robot vision model is built, and then the 3D location principle, the calibration method and precision of this model are analyzed. This active robot vision system with two DOF enlarges its visual field and the stereo is the most simple camera configuration for 3D position information.

Abstract: The paper analyzes the dynamic relation of asymmetric multi-supported vibration isolation system with flexible foundation, establishes the comprehensive model of passive control and positive control system by using the effective matrix analysis method, analyzes the transmission mechanism and characteristic of vibrational power flow in the flexible vibration isolation system. In order to meet the need of the practical engineering, the paper analyzes and calculates the effect of the machine mass on the input and the transmission power flow in detail. At last, the paper puts forward the measure to reduce vibration energy transmission.

Abstract: Vision is an important means of the humanoid robot to get external environmental information; vision system is an important part of humanoid robot. The system of a humanoid robot with the functions of visual perception and object manipulation is very complex because the body of the humanoid robot possesses many joint units and sensors. Two computers linked by Memolink communication unit is adopted to meet the needs of real time motion control and visual information processing tasks. The motion control system included coordination control computer, the distributed DSP joint controllers, DC motor drivers and sensors. Linux and real-time RT-Linux OS are used as the operating system to achieve the real-time control capability.

Abstract: The fabrication of ceramic moulds with zirconia primary coat for investment casting of gamma titanium aluminide based alloys (hereafter called TiAl alloys) was described in this study. The microstructures and fracture strength of ceramic moulds were characterized. The fracture strength and surface roughness of the ceramic moulds with zirconia primary coat were sufficient for the TiAl investment casting. TiAl blades were used for the technology demonstration in producing TiAl components. TiAl castings produced by the ceramic moulds exhibited an average surface roughness (R_a ) of 6 μm.

Abstract: A novel biocomposite Ti-35wt%Nb-2.5wt%Sn-15wt%HA powders was synthesized by high energy ball mill(HEBM) for various periods of time. The microstructure and characteristics of the milled powder particles were investigated. Results showed that in the composite powders milled for 4h, Ti was still exhibited primary α phase, with the increase of ball milling time up to 8h, Ti transformed into primary β phase and a little α phase, after ball milling for 12h, Ti transformed into β phase fully. the transform temperature was 380.06°C. And TEM and PSD results indicated that nanostructure was obtained after 12h milling..

Abstract: This paper takes G4-73 centrifugal fan as the reference model. A practical parametric software platform was developed with VB Programming languages and Fluent software. Numerical simulation based on k-e turbulence model in the same flow rate was taken using the platform. The results show that the total pressure and efficiency of fans will be ideal when the blade angle take 45 degree, which is the design value. However, the best impeller width gotten from numerical simulation is smaller than the design value, that is, 18.5 cm is the most suitable value. The conclusion is of great significance for the subsequent optimization and reconstruction of fan.

Abstract: In this paper the key factors of the enterprise alliance running status were studied based on system dynamic theory. These factors include intrinsic restraint, achievement, core competencies and compatibility. A causality diagram and a system dynamic model which can reflect the growing process of enterprise alliance running phase were established. A program simulating the system dynamic model of the enterprise alliance running phase is also achieved, and the validation was infered by a qualitative analysis. The results show that it is a workable method to study the enterprise alliance running status with system dynamic theory．

Abstract: Water pollution control engineering is one of the main courses of Environmental Engineering specialty. In order to develop the technical skills and professional qualities of students in this area, the innovative mode of practice teaching was explored while the curriculum and practice teaching systems were constructed. The simulation system of water pollution control engineering and field practice system were integrated during the progressive innovation practice teaching, which produced good results.

Abstract: The measured coefficient of consolidation can have a substantial degree of variation even in a uniform clay layer. This paper examines the variability of one-dimensional consolidation solutions through a probabilistic analysis. The spatial probabilistic characteristics for the coefficient of vertical consolidation are studied. The influence of a spatially random coefficient of consolidation on one-dimensional consolidation has been studied using the probabilistic method. In the probabilistic analysis, the adequacy of distribution model for coefficient of consolidation is tested using experimental data. A sensitivity analysis of the degree of consolidation to uncertain parameters is presented for clay soil. It is the analysis result that probability distribution type of vertical consolidation has a considerable influence on degree of consolidation. The results are discussed in terms of confidence level.

Abstract: A four-probe dc method for measuring the electrical resistivity of liquid quasicrystal Al₆₃Cu₂₅Fe₁₂ was investigated in this article and found out that the resistivity of the melt temperature negative factors. Resistivity in alloy melting temperature near the lower interval occurred in phase I and λ, but is not happen to shift in β phase. That would not cause phase change of electronic transport, may be held without fracture, and held the bond length is changed. The viscosity of liquid quasicrystal Al₆₃Cu₂₅Fe₁₂ was tested by using torsional oscillation viscosity measurement. Anomalous change at the temperature of (1401-1473)K occurred from the viscosity-temperature cures, some liquid-liquid change has taken place at this temperature.