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flying-bits´nbytes
12th Dec 2000, 00:50
Is there anybody how can tell me how an accelerometer works or how shows me a link where i can find this information ??

Lu Zuckerman
12th Dec 2000, 01:20
There are many types of accelerometers, here is one type.

Force Balance Accelerometer:

It has weight that can move +/- in only one axis so in order to measure acceleration on X-Y-Z planes you will need three.

When the object being measured for acceleration starts to move, the weight will move in the opposite direction. There are two magnetic coupling devices that measure the movement and there is a summing device that will apply an electrical force in order to return the weight to the neutral point.

The strength of the electrical restoring force is measured and the electrical force is directly proportional to the accelleration. This measured electrical force is then processed and you get a readout in Gs or what ever you need to display the acceleration.

Someone else can provide the descriptions of the other types of measuring devices.

Genghis the Engineer
12th Dec 2000, 03:13
A weight, a spring, and a little needle attached to the weight. Something to damp out the weight (stop it bobbing up and down) is a good idea too.

I came across a test pilot the other day who used a fish-balance and a bag of lead shot because the aircraft didn't have a g-meter and he only needed the instrument for one flight.

G

Self Loading Freight
12th Dec 2000, 05:24
There's a long piece on accelerometer design and usage on Analog Device's web site --

<A HREF="http://www.analog.com/iMEMS/library/Sensor971/" TARGET="_blank">http://www.analog.com/iMEMS/library/Sensor971/</A>

Unfortunately, it seems to be mostly in note form, but it does cover a lot of ground and all the technologies.

R