A study of a nonlinear vibration isolator with a quasi-zero stiffness characteristic (2008)
Kovacic, I., Brennan, M.J., Waters, T.P.
A vibration isolator consisting of a vertical linear spring and two nonlinear pre-stressed oblique springs is considered in this paper. The system has both geometrical and physical nonlinearity....
Carrella, A., Brennan, M.J., Waters, T.P., Shin, K.
The frequency range over which a linear passive vibration isolator is effective is often limited by the mount stiffness required to support a static load. This can be improved upon by incorporating a...
Carella, A., Brennan, M.J., Waters, T.
This article describes a demonstrator to show the effects of negative stiffness on the free vibration of a simple oscillator. The test rig consists of a horizontal beam that is hinged at one end and...
Brennan, M.J., Carrella, A., Waters, T.P., Lopes, V.
This paper presents a consistent and concise analysis of the free and forced vibration of a mass supported by a parallel combination of a spring and an elastically supported damper (a Zener model)....
Wave propagation, reflection and transmission in curved beams (2007)
Lee, S.K., Mace, B.R., Brennan, M.J.
Wave motion in thin, uniform, curved beams with constant curvature is considered. The beams are assumed to undergo only in-plane motion, which is described by the sixth-order coupled differential...
Brennan, M.J., Ananthaganeshan, K.A., Elliott, S.J.
In many active vibration control systems, it is the high frequency dynamic behaviour of the system that limits controller gain. However, in the specific case of vibration isolation, the low frequency...
Wave propagation, reflection and transmission in non-uniform one-dimensional waveguides (2007)
Lee, S.K., Mace, B.R., Brennan, M.J.
Waves can propagate freely without reflection in a certain class of non-uniform one-dimensional waveguides even though the properties of the waveguide vary rapidly. In these cases, the amplitude of...
Brennan, M.J., Gao, Y., Joseph, P.F.
Estimation of time delay in a vibroacoustic system is a problem that occurs in several engineering fields. This can be determined directly in the time domain or in the frequency domain by examining...
Vibration isolation of a marine diesel generator set (2007)
Lee, D.C., Brennan, M.J., Mace, B.R.
The resilient mounts of a diesel engine installed onboard a ship should be designed for both static and dynamic loads. If possible, the resonance frequencies of the six rigid body modes of the...
Numerical evaluation of high-order modes of vibration in uniform Euler-Bernoulli beams (2007)
Gonçalves, P.J.P., Brennan, M.J., Elliott, S.J.
Many vibration text books give expressions for the mode shape functions of uniform Euler–Bernoulli beams. However, the common forms of these expressions permit the evaluation of only the first 12...
Static analysis of a passive vibration isolator with quasi-zero-stiffness characteristic (2007)
Carrella, A., Brennan, M.J., Waters, T.P.
The frequency range over which a linear passive vibration isolator is effective, is often limited by the mount stiffness required to support a static load. This can be improved upon by employing...
The control of flexural wave motion on a beam using a vibration neutraliser is the subject of this paper. A vibration neutraliser will generally suppress a flexural wave significantly over a narrow...
Optimization of a quasi-zero-stiffness isolator (2007)
Carrella, A., Brennan, M.J., Waters, T.P.
The frequency range over which a mount can isolate a mass from a vibrating base (or vice versa) is often limited by the mount stiffness required to support the weight of the mass. This compromise can...
Mapping the underworld - state-of-the-art review (2007)
Metje, N., Atkins, P.R., Brennan, M.J., Chapman, D.N., Lim, H.M., Machell, J., ...
A major UK initiative, entitled Mapping the Underworld (MTU), is seeking to address the serious social, environmental and economic consequences arising from an inability to locate accurately and...
Mapping the Underworld – State-of-the-art review (2007)
Metje, N, Atkins, P R, Brennan, M J, Chapman, D N, Lim, H M, Machell, J, ...
A major UK initiative, entitled Mapping the Underworld (MTU), is seeking to address the serious social, environmental and economic consequences arising from an inability to locate accurately and...
Gao, Y., Brennan, M.J., Joseph, P.F.
The position of a leak in buried water distribution pipes, may be determined by accurate estimation of the time delay between two measured acoustic signals. By using a model for the wave propagation...
Moshrefi-Torbati, M., Keane, A.J., Elliott, S.J., Brennan, M.J., Anthony, D.K., Rogers, E.
In this paper, results for active vibration control predicted from experimental measurements on a lightweight structure are compared with purely computational predictions. The structure studied is a...
A demonstration of active vibration isolation using decentralized velocity feedback control (2006)
Brennan, M.J., Elliott, S.J., Huang, X.
This paper describes a demonstrator designed to show the way in which a four-channel active vibration system can be implemented using an analogue decentralized controller. Each mount consists of a...
Moshrefi-Torbati, M, Keane, A J, Elliott, S J, Brennan, M J, Anthony, D K, Rogers, E
In this paper, results for active vibration control predicted from experimental measurements on a lightweight structure are compared with purely computational predictions. The structure studied is a...
The integration of advanced active and passive structural noise control methods (2006)
Moshrefi-Torbati, M, Keane, A J, Elliott, S J, Brennan, M J, Rogers, E
This paper reports on an investigation into the feasibility of using active and passive means of vibration control in aerospace structures. In particular, attention is focused on controlling...
The integration of advanced active and passive structural noise control methods (2006)
Moshrefi-Torbati, M., Keane, A.J., Elliott, S.J., Brennan, M.J., Rogers, E.
This paper reports on an investigation into the feasibility of using active and passive means of vibration control in aerospace structures. In particular, attention is focused on controlling...
A novel sensor for measuring the acoustic pressure in buried plastic water pipes (2006)
Muggleton, J.M., Brennan, M.J., Pinnington, R.J.
Acoustic techniques are widely used to locate leaks in buried water pipes. However, difficulties are often encountered when attempting to detect a leak in a plastic pipe, as the leak noise signals...
Gao, Y., Brennan, M.J., Joseph, P.F.
The position of a leak in buried water distribution pipes, may be determined by accurate estimation of the time delay between two measured acoustic signals. By using a model for the wave propagation...
The Integration of Advanced Active and Passive Structural Noise Control Methods (2006)
Moshrefi-Torbati, M., Keane, A.J., Elliott, S.J., Brennan, M.J., Rogers, E.
This paper reports on an investigation into the feasibility of using active and passive means of vibration control in aerospace structures. In particular, attention is focused on controlling...
The integration of advanced active and passive structural noise control methods (2006)
Moshrefi-Torbati, M., Keane, A.J., Elliott, S.J., Brennan, M.J., Rogers, E.
This paper reports on an investigation into the feasibility of using active and passive means of vibration control in aerospace structures. In particular, attention is focused on controlling...
Moshrefi-Torbati, M., Keane, A.J., Elliott, S.J., Brennan, M.J., Anthony, D.K., Rogers, E.
In this paper, results for active vibration control predicted from experimental measurements on a lightweight structure are compared with purely computational predictions. The structure studied is a...
Finite element analysis of the vibrations of waveguides and periodic structures (2006)
Duhamel, D., Mace, B.R., Brennan, M.J.
Many structural components can be regarded as waveguides. They are uniform in one direction so that the cross section of the waveguide has the same physical and geometric properties at all points...
Vibration decay using on-off stiffness control (2006)
Ledezma-Ramirez, D.F., Ferguson, N.S., Brennan, M.J.
A relatively new approach for shock and vibration isolation is to use semi-active or fully-active elements, which are designed to provide better vibration isolation over a broad range of excitation...
On numerical issues for the wave/finite element method (2006)
Waki, Y., Mace, B.R., Brennan, M.J.
The waveguide finite element (WFE) method is a numerical method to investigate wave motion in a uniform waveguide. Numerical issues for the WFE method are specifically illustrated in this report. The...
Moshrefi-Torbati, M, Keane, A J, Elliott, S J, Brennan, M J, Anthony, D K, Rogers, E
In this paper, results for active vibration control predicted from experimental measurements on a lightweight structure are compared with purely computational predictions. The structure studied is a...
The integration of advanced active and passive structural noise control methods (2006)
Moshrefi-Torbati, M, Keane, A J, Elliott, S J, Brennan, M J, Rogers, E
This paper reports on an investigation into the feasibility of using active and passive means of vibration control in aerospace structures. In particular, attention is focused on controlling...
Moshrefi-Torbati, M, Keane, A J, Elliott, S J, Brennan, M J, Anthony, D K, Rogers, E
In this paper, results for active vibration control predicted from experimental measurements on a lightweight structure are compared with purely computational predictions. The structure studied is a...
The integration of advanced active and passive structural noise control methods (2006)
Moshrefi-Torbati, M, Keane, A J, Elliott, S J, Brennan, M J, Rogers, E
This paper reports on an investigation into the feasibility of using active and passive means of vibration control in aerospace structures. In particular, attention is focused on controlling...
Real-time control of a shape memory alloy adaptive vibration absorber (2005)
Rustighi, E., Brennan, M.J., Mace, B.R.
The tuned vibration absorber (TVA) is a well established vibration control device. An adaptive TVA (ATVA) is one whose properties can be continuously adapted to maintain optimal tuning. This paper...
A shape memory alloy adaptive tuned vibration absorber: design and implementation (2005)
Rustighi, E., Brennan, M.J., Mace, B.R.
In this paper a tuned vibration absorber (TVA) is realized using shape memory alloy (SMA) elements. The elastic modulus of SMA changes with temperature and this effect is exploited to develop a...
Liu, Y., Waters, T.P., Brennan, M.J.
Active vibration isolation systems are less commonly used than passive systems due to their associated cost and power requirements. In principle, semi-active isolation systems can deliver the...
On the selection of acoustic/vibration sensors for leak detection in plastic water pipes (2005)
Gao, Y., Brennan, M.J., Joseph, P.F., Muggleton, J.M., Hunaidi, O.
Leaks from buried water distribution pipes are commonly located by applying the correlation technique to two measured acoustic/vibration signals on either side of a leak. The effectiveness of the...
Free vibration characteristics of an isolation system with a spring relaxed damper (2005)
Carrella, A., Waters, T.P., Brennan, M.J.
Vibration isolators are frequently represented by the classical Voigt model of a spring and viscous damper in parallel. In cases where this model is appropriate, isolation at high frequencies is...
Axisymmetric wave propagation in buried, fluid-filled pipes: effects of wall discontinuities (2005)
Muggleton, J.M., Brennan, M.J.
Water leakage from buried pipes is a subject of great concern in Britain and across the world because of decreasing water supplies due to changing rainfall patterns, deterioration of antiquated...
The development of a tunable vibration absorbing isolator (2005)
Du Plooy, N.F., Heyns, P.S., Brennan, M.J.
This paper describes a tunable vibration absorbing isolator. The device is based on the liquid inertia vibration eliminator, which is modified so that the frequency at which maximum isolation occurs...
A shape memory alloy adaptive tuned vibration absorber: design and implementation (2005)
Rustighi, E., Brennan, M.J., Mace, B.R.
In this paper a tuned vibration absorber (TVA) is realized using shape memory alloy (SMA) elements. The elastic modulus of SMA changes with temperature and this effect is exploited to develop a...
Suppression of bending waves in a beam using a tuned vibration absorber (2005)
El-Khatib, H.M., Mace, B.R., Brennan, M.J.
This paper is concerned with the control of flexural waves in a beam using a tuned vibration absorber (TVA). The TVA may be located in the farfield or the nearfield of a time harmonic point force and...
Wave model for rigid-frame porous materials using lumped parameter concepts (2005)
Rossetti, S., Gardonio, P., Brennan, M.J.
The work presented in this paper concerns the behaviour of porous media when exposed to a normal incidence sound field. A propagating wave model based on lumped parameter concepts of acoustic mass,...
Real-time control of a shape memory alloy adaptive dynamic vibration absorber (2005)
Rustighi, E., Brennan, M.J., Mace, B.R.
The tuned vibration absorber (TVA) is a well established vibration control device. An adaptive TVA (ATVA) is one whose properties can be continuously adapted to maintain optimal tuning. This paper...
Real-time control of a shape memory alloy adaptive vibration absorber (2005)
Rustighi, E., Brennan, M.J., Mace, B.R.
The tuned vibration absorber (TVA) is a well established vibration control device. An adaptive TVA (ATVA) is one whose properties can be continuously adapted to maintain optimal tuning. This paper...
Prediction of wave motion in structural waveguides using the finite element method (2005)
Brennan, M.J., Mace, B.R., Hinke, L., Duhamel, D.
A method is presented by which the wavenumbers for a one-dimensional waveguide can be predicted from a finite element (FE) model. The method involves postprocessing a conventional, but low order, FE...
Design of a beam-like neutraliser to control flexural waves on an infinite beam (2005)
The control of flexural wave motion in beam-like structures is of considerable interest in engineering practice. One simple method to control this type of wave is to attach a discontinuity or an...
A design criterion for the vibration isolation of a marine diesel generator set (2005)
Lee, D.C., Brennan, M.J., Mace, B.R.
The resilient mounts of a diesel engine installed onboard a ship should be designed for both static and dynamic loads. If possible, the resonance frequencies of the six rigid body modes of the...
Moshrefi-Torbati, M., Keane, A.J., Elliott, S.J., Brennan, M.J, Anthony, D.K., Rogers, E
In this paper, results for active vibration control predicted from experimental measurements on a lightweight structure are compared with purely computational predictions. The structure studied is a...
Leak noise propagation and attenuation in submerged plastic water pipes (2004)
Muggleton, J.M., Brennan, M.J.
Detection of water leaks in buried distribution pipes using acoustic methods is common practice in many countries. Correlation techniques are widely used in leak detection, and these have been...
Muggleton, J.M., Brennan, M.J., Linford, P.W.
Detection of water leaks in buried distribution pipes using acoustic methods is common practice in many countries. Correlation techniques are widely used in leak detection, but for these to be...
Mobility analysis of active isolation systems (2004)
Elliott, S.J., Benassi, L., Brennan, M.J., Gardonio, P., Huang, X.
A frequency-domain formulation is used to analyze the stability and performance of an active vibration isolation system which uses feedback control. The active mount is modelled as a single-axis...
Designs of variable stiffness element for a tunable vibration absorber (2004)
Brennan, M.J., Bonello, P., Rustighi, E., Mace, B.R., Elliott, S.J.
Identifying the foundation stiffness of a partially embedded post from vibration measurements (2004)
Waters, T.P., Brennan, M.J., Sasananan, S.
Foundations of posts such as lighting columns can suffer damage or deteriorate over time, rendering the post unsafe. Quick, inexpensive and non-intrusive measurement procedures are required to...