Top Qs
Timeline
Chat
Perspective
Inerter (mechanical networks)
Device in the study of mechanical networks in control theory From Wikipedia, the free encyclopedia
Remove ads
In the study of mechanical networks in control theory, an inerter is a two-terminal device in which the forces applied at the terminals are equal, opposite, and proportional to relative acceleration between the nodes. Under the name of J-damper the concept has been used in Formula 1 racing car suspension systems.
This article needs additional citations for verification. (June 2018) |
It can be constructed with a flywheel mounted on a rack and pinion. It has a similar effect to increasing the inertia of the sprung object.
Remove ads
Discovery
Summarize
Perspective
Malcolm C. Smith, a control engineering professor at the University of Cambridge, first introduced inerters in a 2002 paper.[1] Smith extended the analogy between electrical and mechanical networks (the mobility analogy). He observed that the analogy was incomplete, since it was missing a mechanical device playing the same role as an electrical capacitor. The analogy makes mass the analog of capacitance, but the capacitor representing a mass always has one terminal connected to ground potential. In a real electrical network, capacitors can be connected between any two arbitrary potentials, they are not limited to ground. Noticing this, Smith set about finding a mechanical device that was a true analog of a capacitor. He found that he could construct such a device using gears and flywheels, one of several possible methods.
The constitutive equation is,
- ,
where the constant b is the inertance and has units of mass.
Remove ads
Construction
A linear inerter can be constructed by meshing a flywheel with a rack gear. The pivot of the flywheel forms one terminal of the device, and the rack gear forms the other.
A rotational inerter can be constructed by meshing a flywheel with the ring gear of a differential. The side gears of the differential form the two terminals.
Applications
Shortly after its discovery, the inerter principle was used under the code name of J-damper in the suspension systems of Formula 1 racing cars. When tuned to the natural oscillation frequencies of the tires, the inerter reduced the mechanical load on the suspension. McLaren Mercedes began using a J-damper in early 2005, and Renault shortly thereafter.[2][3] J-dampers were at the center of the 2007 Formula One espionage controversy which arose when Phil Mackereth left McLaren for Renault.
Researchers are developing new vibration-control devices based on inerters to build high-rise skyscrapers which can withstand high winds.[4][5]
See also
References
External links
Wikiwand - on
Seamless Wikipedia browsing. On steroids.
Remove ads