Modal

Quantum mechanics

Damper

Suspension (topology)

Control (management)

Tuned mass damper

Engineering

Polymer chemistry

Pure mathematics

Materials science

Homotopy

Vibration

Computer science

Acoustics

Classical mechanics

Physics

Finite element method

Nonlinear system

Mathematics

Optics

Added mass

Focus (optics)

Inertia

Artificial intelligence

Structural engineering

Stiffness

Control theory (sociology)

Mechanical Systems and Signal Processing

A translational Lanchester damper is a device that adds damping to a structure at a point using a series combination of a viscous damper and a mass. The problem in the practical realisation of such a device is that a stiffness is required to support the mass, which changes the dynamic behaviour of the device, introducing a resonance frequency due to the interaction of the stiffness and inertia forces. This is a dynamic vibration absorber. To achieve a device that behaves broadly as a Lanchester damper rather than a dynamic vibration absorber, a very low stiffness is required, and this is the focus of this paper. The low stiffness is realised using a combination of linear springs and rigid links arranged with specific geometry into a compact device. Although the geometric configuration of the components leads to an inherently nonlinear device, the aim is to limit its working condition and exploit the linear-like behaviour. To this end, how the geometry affects the nonlinear behaviour is studied in detail, providing general guidelines for its design. A prototype Lanchester damper incorporating the low stiffness element was manufactured and tested on a single mode and two multi-modal vibrating structures.

On the detailed design of a quasi-zero stiffness device to assist in the realisation of a translational Lanchester damper