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Vibration Sensor, I want a really high tolerance, I intend on using this to measure the vibration generated when dumbells are thrown onto the floor in a gym.

Because, I have familiarirty with the Arduino, that is what I was looking into, but found no good solutions for high tolerance vibration sensors. Could you'll please suggest some other alternatives?

I'd prefer having to work with a platform that allows for high level programming of the microcontroller like Wiring for Arduino. But please don't refrain from suggesting anything otherwise ...

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  • \$\begingroup\$ The temperature sensor doesn't seem to have anything to do with your actually question, am I missing something? \$\endgroup\$ – Kellenjb Jun 19 '12 at 18:07
  • \$\begingroup\$ Hi Kellenjb, the vibration sensor is primarily what I'm looking for, but I also want to continously monitor the temperature. I think I'm OK with figuring out the temperature sensor bit. I only put it in there to get recommendations, I might not have been aware of ... \$\endgroup\$ – c0d3rz Jun 19 '12 at 18:12
  • \$\begingroup\$ Do you intend to mount this device (including Arduino?) inside a dumbell? Or on the floor? \$\endgroup\$ – Rocketmagnet Jun 19 '12 at 18:24
  • \$\begingroup\$ I was intending on mounting it onto the dumbell. Just a cheap fix with some electrical tape. Probably not the best approach :) ... \$\endgroup\$ – c0d3rz Jun 19 '12 at 18:26
  • \$\begingroup\$ Exactly what do you need to measure about the vibration? Do you just want to know if it hits the floor, or do you need to know the actual impact acceleration profile? \$\endgroup\$ – Rocketmagnet Jun 19 '12 at 18:32
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A dumbell falling from 1m height will hit the ground at about 4.4m/s. But what acceleration will it experience when it hits? This depends on the distance it travels during deceleration. Assuming the coatings on the dumbell and floor have some give in them, lets assume that it takes 1mm to decelerate. In this case, the dumbell will experience nearly 100G deceleration. So, you just need to find a device which can cope with these kind of accelerations.

How about the ADXL377 from Analog Devices? It's even advertised for this very application.

adxl377

Personally, I'd be more worried about the Arduino and the tape holding it onto the dumbell. How much load will it have to take during the impact?

F = ma
= 0.1kg * 1000m/s/s
= 100N
= 10kg

That's a lot of load. You'd better screw the accelerometer on with some nice bolts, to transmit the acceleration to it accurately, and use anti-vibration mounts for the Arduino.

Anti vibration mounts

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  • \$\begingroup\$ Couple of silly questions: How do you know it will hit at 4.4 m/s? I've never thought of using an accelerometer for this purpose. I think I need to research a little more about it and get some raw values to make sense of the relation between acceleration and pressure ... Thanks for the reply! \$\endgroup\$ – c0d3rz Jun 19 '12 at 19:09
  • \$\begingroup\$ @c0d3rz - Newtons equations of motion. Any object heavier than a marble will hit the ground at the same speed when falling from 1m. \$\endgroup\$ – Rocketmagnet Jun 19 '12 at 19:14
  • \$\begingroup\$ @c0d3rz - When you say pressure, what do you really mean? Pressure is a measure of an amount of force spread over an area. Is this really what you mean? I'm 95% sure you want to measure acceleration. \$\endgroup\$ – Rocketmagnet Jun 19 '12 at 19:16
  • \$\begingroup\$ Your probably right Rocketmagnet. I'm going to read around a little until I understand how the accelerometer is the best sensor here. I just don't have the same clarity as you towards its application. Thanks ... \$\endgroup\$ – c0d3rz Jun 19 '12 at 19:55

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