Advanced Materials Research Vols. 605-607

Abstract: A real-time measurement method based on multi-vision system is presented for measuring the motion parameters of three-DOF spacecraft simulator. Four cameras are arranged around the motion space of the simulator. When the simulator makes large range translation and rotation motion, 3D coordinate measurement can be realized for any marker provided that such marker is identified by 2 or more cameras. And the motion parameters of simulator can be measured when more than 3 markers are identified in each measurement. The experiment results verify this method and show it can achieve high measurement accuracy.

Abstract: First we give the optical field function at distance z for a monochromatic light according to the Fresnel diffraction theory. The total optical field intensity is an integral of that of the monochromatic light. The total optical field intensity is not only related to the full width at half maximum, the distance, the structure of the serrated aperture, but also the radius of the ultrashort laser pulse. Numerical calculation shows that when the ratio of the averaged radius of the serrated aperture to the radius of the ultrashort laser pulse equals to 1 and the full width at half maximum is within a few tens of femtoseconds, the total optical field intensity reaches a constant along the axis direction and it is more stable than that without considering the radius of the ultrashort laser pulse in case that the Fresnel number of the laser pulse is about a hundred.

Abstract: The heavy duty apron feeder is a mechanism for material transportation. According to the differences on test requirements and effects, the traditional sensor development test weighing system presently is adopted widely. In the design, resistance strain gauge is installed on the feeder chain plate; and the whole-armed bridge compensates temperature to test the voltage value outputted by bridge resistance gauge; based on labview software, the virtual online dynamic weighing system is developed, realizing online monitoring at full time, warning, alarming and shutdown protective operation.

Abstract: In this paper, we consider the energy-based source localization in sensor networks. A least square solution to the maximum likelihood (ML) formulation of energy-based source localization is proposed. Since the ML-formulation is nonlinear and non-convex, we approximate it to a convex least square problem which can be solved directly. Simulation results show that with a rough initial estimate range of the acoustic source’s location, the proposed method can achieve a high degree of accuracy. Moreover, with thousands of times lower computational complexity than the semi-definite relaxation method, the proposed method can be effectively used in real time location systems (RTLS).

Abstract: This paper is aimed at the matter that verification method of time interval generator is still manual test, low efficiency, heavy workload, and for mechanical stopwatch calibrator can not be test because of lack of a machine / electrical converter. The author developed a machine/electrical switch, and programmed the automatic verification and management software using VB language, which realized the automatic verification and information management for various types of time interval generator. The machine/electrical switch is tested by NIM, the result show that the main indexes meet the design requirements. By practical application, the system has been working condition, which can be used as standard equipment of time and frequency parameter.

Abstract: In this paper, a new height estimation method based on joint time delay and phase estimation is proposed, which can solve the contradiction between the dimensions of the observing space and the hypothesis of spatial stationarity. It can improve the performance and robustness of time delay estimation by utilizing the neighboring pixels’ common information though spatial processing. The simulated data varifies the perfermance of the proposed method. The result is that its performance is better than the cross correlation estimation method.

Abstract: A mathematic model of capstan drive stiffness is presented. The influence of preload force, coefficient of friction, wraps of cable and load on the transmission stiffness of a differential cable-driven picking manipulator is analyzed. It is shown that capability of transmission, loads and precision can be considered comprehensively in the design of drive capstan.

Abstract: To overcome the difficult in modeling the mode theory for magnetic flywheel, by non-parametric frequency domain identification method for identification of system model, this paper select the PID neural network nonlinear intelligent control methods based on GA. Used a method based on iterative process to suppress the resonance, combined with zero-pole theory, this research designed a GA-based PID neural network identification controller to address the modal vibration suppression problems in the external rotor flywheel .The experiments for this paper proved the effectiveness of iterative process, and the controller can restrain the system mode vibration well.

Abstract: In order to make achieve univesal feed, the feeding step of feeder should be able to regulate stepless according to the requirement of different devices.Though the motion analysis of the belt driving mechansim with changing step and the finite element analysis about one group of transmisson pully cone,we can proved that the accuracy of the structural parameters design of the transmission cone pully.

Abstract: Measured vibration displacement data of conticaster vibration table at different casting speeds, use of "correlation" theory to evaluate the measured data. Get similarity change curve and oscillation amplitude change curve of the four measured points at different casting speeds. The results reflect the crystallizer’s real situation during exercise. Provide a reliable basis for field equipment maintenance and control.