Time filter

Source Type

Feng X.-L.,Mechanical and Electrical engineering College | Hu J.,Wuhan University of Technology
Journal of Vibroengineering | Year: 2016

The parallel mechanism was adopted as seat suspension system in this paper. And the active joints with damping springs as the reduction vibration actuator, the reduction vibration seat model with 3-PRPS parallel mechanism which had six degree of freedom was established. With position of the mechanism as the premise, stability indexes of the reduction vibration seat in motion were proposed. As a result, the task space of the moving platform was obtained according to the inverse solution of the mechanism position. To reduce vibration effectively, velocity matrix of branched chain was built by means of vector method. The structural parameters were obtained by the numerical computation to improve the reduction vibration space and flexibility. Based on the above analysis, the simulation model can be obtained. In order to verify the reliability of the simulation model, the experiment of vibration acceleration transmissibility was conducted and the result was then compared with that of the numerical computation. Their results were consistent with each other. It indicated that the simulation model was reliable and could be used for the subsequent analysis. Then, influence factors of vibration acceleration transmissibility were researched based on the verified simulation model. In order to obtain a suspension system with better reduction vibration performance, making the maximum vibration acceleration transmissibility in the vertical and horizontal be minimal was set as the optimization objective. And the above influence factors were taken as the design variables. Finally, the ride comfort of vehicles was improved. Meanwhile, this research can also provide some references for the similar engineering problems. © JVE INTERNATIONAL LTD. Source

Deng T.,Quanzhou Normal University | Chen M.,Mechanical and Electrical engineering College
Jixie Qiangdu/Journal of Mechanical Strength | Year: 2015

T-joint structure is one of the bus basic structures. This paper discussed the effects of triangle bracket size and four forms of triangle brackets (double brackets added at vertical rod single side, double brackets added at vertical rod both sides, single bracket added at vertical rod both sides, single bracket added at vertical rod crossing symmetric sides) on the rigidity and strength of bus T-joint structure. The calculation by finite element method and experimental analysis showed that: ①Only double brackets added at vertical rod both sides in the four forms of triangle bracket can evidently increase both the rigidity and strength of bus T-joint, ②Under the bending loads two forms can be selected compatibly for T-joint structure, ③Under the torsion loads double brackets added at vertical rod both sides should be selected for T-joint structure. This research findings can be referred for joint structure design of bus body. ©, 2015, Journal of Mechanical Strength. All right reserved. Source

Li F.,Mechanical and Electrical engineering College | Xu Z.,Huazhong University of Science and Technology
Electronics Letters | Year: 2014

A reduced-complexity timing recovery method for binary continuous-phase frequency shift keying (CPFSK) is presented. The proposed algorithm is based on phase unwrapping and is easy to implement. Theoretical analysis and computer simulation both show that the new algorithm is able to perform close to the theoretical limit given by the modified Cramer-Rao bound (MCRB). © The Institution of Engineering and Technology 2014. Source

Lu Y.,Mechanical and Electrical engineering College | Guo J.,Institute of Space Navigation Engineering Research
Jixie Qiangdu/Journal of Mechanical Strength | Year: 2013

High-steps cumulation spectrum was applied in random vibration control experiment, random driving signal in time domain is got. By establishing the conversion relations between three steps cumulation spectrum (bi-spectrum) and auto-spectrum, the relations gets approvement according to validation experiment on generating random driving signal in time domain. Following, linear mapping relations of system driving, frequency response and system response are gained under MIMO (multi-input multi-output) linear system, the conversion relationship of amplitudes and phases between auto-spectrum and bi-spectrum are established, IFFT (iverse fast Fourier transform) operation are used for obtaining the driving signals meeting the control experiment need. Finally, DIDO (double input double output) random vibration environment experiment about cantilever beam is made, the result shows the effective aspects of the method. At the same time, the character of bi-spectrum on restraining gauss white noise gets validation, what is reflected by probability density distribution character curves. Source

Shen Y.,Mechanical and Electrical engineering College | Zhang W.,Yangzhou University
Lecture Notes in Electrical Engineering | Year: 2016

In this paper, the stabilization problem is investigated for a class of nonlinear stochastic systems with sampled data control. By means of the Lyapunov stability theory, a sufficient condition is derived to ensure that the considered stochastic nonlinear system with sampled data is asymptotically stable in mean square. The allowable bound of the sampling interval is obtained and the control gain matrix is solved in terms of convex optimization methods. Finally, a numerical example is presented to further demonstrate the effectiveness of the proposed approach. © Springer-Verlag Berlin Heidelberg 2016. Source

Discover hidden collaborations