Papers by Keyword: Vibration Spectrum

Abstract: The paper defines the transmission errors of planetary gear trains, derives from kinetic tooth contact analysis. The method to calculate transmission errors of planetary gear trains is put forward. An integrated platform was constructed for measuring gear noise, vibration and transmission error to verify the effectiveness and feasibility of the analytical. Finally, experimental investigations of the gear noise and vibration spectrum in time domain are introduced, which was solved and simulated in Matlab software.

Abstract: By the disadvantage of the speed fluctuations to the gear noise and vibration spectrum in time domain, a new method to measuring the periodic signal was put forward in pulse time domain. The multi-channel simultaneous measurement model were brought out, aimed at analyzing the gear meshing state and its frequency characteristics. Then, the 14 DOF nonlinear vibration equations was derived from kinetic analysis on the planetary gear pair meshing model, which was solved and simulated in Matlab software, containing with transmission error, time-varying mesh stiffness, clearance and other factors. Finally, an integrated platform was constructed for measuring gear noise, vibration and transmission error to verify the effectiveness and feasibility of the analytical.

Abstract: By introducing the basic concepts and designing principles of special-shaped column structure, this paper attempts to establish three finite element models (the special-shaped column structure, rectangular column structure with the equal area and rectangular column structure with the moment of inertia) by using the SAP2000. And the basic dynamic structure properties of three structures are analyzed. It’s base of the dynamic analysis for the structure. Then, the paper analyzes the elastic seismic performance under the horizontal earthquake action by using the vibration spectrum method and the elastic time-history analysis method. The results show that three models are all in the elastic steps. We compared the anti-seismic property of three models under frequent earthquake.

Abstract: The most important things in the dynamic research of industrial robots are the vibration behavior, the transfer function and the vibration power spectral density between some of the robot joints and components. In the world this research is made without the assisted research. In each of the study cases in this paper was used the proper virtual Fourier analyzer and was presented one new method of the assisted vibration analysis. With this research it is possible the optimal choosing the base modulus type to avoid the frequencies from the robot spectrum. In the manufacturing systems, the most important facts are the vibration behavior of the robot, the compatibility with some other components of the system. All the VI where achieved in the LabVIEW soft 8.2 version, from National Instruments, USA. This method and the created virtual LabVIEW instrumentation are generally and they are possible to apply in many other dynamic behavior research.

Abstract: Through the survey and research on seismic damage phenomena of damaged towns by Wenchuan Earthquake and geological environment , this article identify that the seismic damage effect of towns damaged by Wenchuan Earthquake mainly includes four types which are fault dislocation effect、site and foundation effect、topography motion amplified action and geologic hazard effect. Site selection of the reconstruction of damaged towns and seidmic design of building and other problems are complex and systemic engineering problems, and they refer to many complex factors such as earthquake faults、geologic hazards、national well-being and the people's livelihood, economic development and so on. The basic principles of consideration should be: for the mountain towns which are located at seismic fault zone and exist serious geological disaster, they must be avoided and relocated off-site; for the towns which are away from the fault for a distance and have no fatal geological disaster risk, we should follow the principles of "scientific planning, normative avoidance and reasonablely adjust the seismic standards" and reconstruct in the former location. Reconstruction site should also pay attention to the concealment of geological hazards, the multiplicity and long-term sustainability of induced factors and so on, so we should enhance the suitability evaluation of the geological environment and risk assessment of geological disaster.

Abstract: Design and implementation of six freedom transportation vibration spectrum collection system is presented in this paper. The Attitude and Heading Reference System (AHRS) is used to capture signals including x, y, z, direction linear acceleration, angular rates around Z-axis and pitch, roll degree. The software’s architecture and modules for host computer is designed with object-oriented analysis and design techniques, and the software is implemented with VC++6.0. The test results show that the system was able to collect vehicular vibration information on time and the collection data was replayed on the vibration platform.

Abstract: This paper presents the using vibration spectrum of transformer operational status with online monitoring methods, analyzes and discusses the transformer vibration spectrum about the producing mechanism and extraction scheme . At the same time, it also discusses the feasibility and necessity of using vibration spectrum methods to monitor the transformer fault .Some vibration spectrum methods ,relating to the transformer research contents and key technical breakthrough direction, are summarized in detail. Finally, it put forward a new immune from organization antibody network model and antibody generating algorithm that is used for vibration spectrum power transformer fault diagnosis.

Abstract: There are two main characteristics of cushioning materials that are required to design a robust cushioning system for the protection of critical element against enviro-mechanical hazards: the attenuation of shocks as a function of the static load and the vibration transmissibility. The effect of a shock on a hypothetical critical element is normally evaluated by the Shock Response Spectrum (SRS) whereas the Frequency Response Function (FRF) performs similar function in relation to vibrations. This paper is concerned with the latter. Cushioning materials are generally nonlinear and, together with the interacting mass, form a nonlinear dynamic system. This paper shows how the Reverse Multiple Input-Single-Output (R-MISO) method can be used to describe the nonlinear characteristics of cushioning systems by generating a series of FRF terms. However, this creates ambiguity in relation to the effect of transmitted vibration on the critical element. This paper proposes to resolve this, by analogy to the SRS, through a numerical calculation of the Vibration Response Spectrum (VRS) for a hypothetical critical element, using as the excitation of the critical element either experimental cushion response data or data synthesised via R-MISO FRFs. Values of the VRS are defined as the ratio of acceleration rms of the critical element to the rms of the cushion excitation, although other descriptors of critical element's exertion can also be considered. The VRS can be considered as the true transmissibility. It is shown that the R-MISO method is superior over the Single Input-Single-Output (SISO) method in determining the transmissibility of polystyrene cushions. Since the cushion system is nonlinear, the excitation of the linear critical element will in general be non-Gaussian, although this paper has shown that it is near- Gaussian in the vicinity of cushion resonance. A chosen hypothetical critical element can be linear or, if its characteristics is known in advance, nonlinear. Results presented in this paper demonstrate how the R-MISO and the VRS can be used to determine the dynamic characteristics of EPS as a nonlinear cushioning material.