New Generation Damping Technologies
Lead Research Organisation:
University of Sheffield
Department Name: Automatic Control and Systems Eng
Abstract
The output frequency response is fundamentally important in the identification, analysis and design of linear systems in the frequency domain with many applications in control, communications, and vibration studies. This research investigation will extend these results by focusing on the output frequency response function [OFRF] for the Volterra class of nonlinear systems, which has recently been derived by the authors. The new OFRF concept reveals, for the first time, that for a wide class of nonlinear systems there is a simple polynomial relationship between the output spectrum and the time domain model parameters, which define the system nonlinearity. This provides the opportunity to analytically conduct optimal designs of nonlinear damping for both sdof and mdof systems, to determine the range of validity of the results, and to validate the new design technology using a vibration supression rig in the laboratory.
Publications
Jing X
(2009)
Parametric Characteristic Analysis for Generalized Frequency Response Functions of Nonlinear Systems
in Circuits, Systems & Signal Processing
Jing X
(2008)
Frequency domain analysis for suppression of output vibration from periodic disturbance using nonlinearities
in Journal of Sound and Vibration
Jing X
(2008)
Mapping from parametric characteristics to generalized frequency response functions of non-linear systems
in International Journal of Control
Jing X
(2009)
Determination of the analytical parametric relationship for output spectrum of Volterra systems based on its parametric characteristics
in Journal of Mathematical Analysis and Applications
Jing X
(2010)
Output frequency properties of nonlinear systems
in International Journal of Non-Linear Mechanics
Laalej H
(2011)
Application of non-linear damping to vibration isolation: an experimental study
in Nonlinear Dynamics
Laalej H
(2010)
Numerical Investigation of the Effects of MR Damper Characteristic Parameters on Vibration Isolation of SDOF Systems Under Harmonic Excitations
in Journal of Intelligent Material Systems and Structures
Laalej H
(2012)
MR damper based implementation of nonlinear damping for a pitch plane suspension system
in Smart Materials and Structures
Lang Z
(2009)
Theoretical study of the effects of nonlinear viscous damping on vibration isolation of sdof systems
in Journal of Sound and Vibration
| Description | In mechanical, civil, and structural engineering, it is well-known that the increase of damping can often only improve the vibration control performance around resonance but is detrimental for the performance over higher frequencies. This project, for the first time, theoretically revealed that the use of odd powered nonlinear damping can systematically resolve this fundamental problem. The novel OFRF (Output Frequency Response Function) concept proposed by the research team and associated theories and methods are the very basis of this investigation. The results provide an important foundation for the development of effective solutions to a wide range of engineering structural vibration control problems. In order to exploit the beneficial effects of nonlinear damping in engineering applications, the design and implementation of nonlinear damping have been conducted on several experimental systems including a BAE Systems test rig for marine vessel engine vibration isolation, providing novel and much better solutions to the structures' vibration control problems. |
| Exploitation Route | The research findings have significant potential engineering applications. These include, for example, providing novel vibration isolation solution for generators and engines, and optimal placement and design of nonlinear dampers for more effective building vibration control during earthquakes etc. In these studies, the nonlinear damping was designed using the OFRF based nonlinear system design approaches and implemented by either active control device or semi-active MR dampers. These results provide a necessary basis for the application of nonlinear damping to resolve the vibration control problems of complex engineering structural systems such as, e.g., wind turbine towers and multi-storey buildings. The research team has already started collaboration with experts in these areas to apply the findings of this project to address relevant challenges. |
| Sectors | Aerospace Defence and Marine Chemicals Construction Electronics Energy Manufacturing including Industrial Biotechology Other |
| Description | The findings have been applied by both the PI 's research team and other researchers to address the vibration control problems in marine, wind energy, and earthquake engineering. For example, the PI's team is currently collaborating with researchers at Keio University in Japan to investigate the application of the novel nonlinear damping technology developed in this project to the design of semi-active isolation system for the Sosokan Building at Keio University. |
| Sector | Construction |
| Description | Royal Society International Exchanges Scheme |
| Amount | £12,000 (GBP) |
| Funding ID | IE150298 |
| Organisation | The Royal Society |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 07/2015 |
| End | 12/2017 |
| Description | Royal Society International Joint Projects |
| Amount | £11,190 (GBP) |
| Funding ID | JP091396 |
| Organisation | The Royal Society |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 05/2010 |
| End | 05/2012 |
| Description | Application of nonlinear damping technology in earthquake engineering |
| Organisation | Keio University |
| Country | Japan |
| Sector | Academic/University |
| PI Contribution | Nonlinear damping technology |
| Collaborator Contribution | Experimental facilities and expertise in earthquake engineering |
| Impact | Two successful experimental studies have been completed . This is a very multi-disciplinary work involving system and control scientists and researchers in earthquake engineering . |
| Start Year | 2015 |