Over the last few years, I’ve been lucky enough to spend time in Taiwan. In my first visit to Taipei, I was astounded by the sheer scale of the Taipei 101 skyscraper. At over 500m tall it dwarfed everything else in the skyline.
Given the proximity of many active fault lines, tall buildings in Taipei have a degree of earthquake protection engineered into them with a tuned mass damper .
Tuned mass dampers consist of a parasitic sprung mass connected in some way to a larger body, and are used to attenuate undesired vibrations. They’re tuned so that the natural frequency of parasitic sprung mass and the body it is connected to are similar.
The tuned mass damper at the top of the Taipei 101 building consists of a 780kg pendulum that’s supported on hydraulic cylinders at the top of the building. Here’s a video of it in action in May 08 when Taipei experienced the effect of an earthquake in China.
And this is a screengrab of a simplified MapleSim model of the mass damper in Taipei 101.
Tuned mass dampers have applications wherever undesired vibrations threaten the integrity of an engineered system. Renault, for example, fitted a tuned mass damper to their F1 car for the 2005 season. It was a sprung 9kg mass that attenuated the vibration of the chassis and the variation of the tire load as it road over bumps, and hence improved grip (it was later deemed illegal because it changed the aerodynamics of the vehicle).
Here’s a screengrab of a quarter car model created with MapleSim, with a tuned mass damper attached to the chassis.
MapleSim made creating both of these models remarkably simple. Instead of having to spend time deriving the system equations by hand, I simply connected the appropriate physical components together as they would appear on a schematic.
Because I can now concentrate on higher-order effects, I’m now developing higher-fidelity versions of both these applications. I’ll keep readers of this blog updated.