How to find 'g' from a MEM's Device (Shimmer IMU)?

  • Thread starter Thread starter bsa09
  • Start date Start date
  • Tags Tags
    Device
Click For Summary
To find 'g' from the Shimmer IMU accelerometer readings, it's essential to understand that the values between 1000 and 2000 likely represent the output of the ADC. Calibration using Earth's gravity is recommended, where aligning the device vertically provides a reading of 9.8 m/s², and horizontal or upside-down positions yield 0 or -9.8 m/s², respectively. This method allows for the establishment of a linear relationship between the output values and acceleration. Consulting the device's documentation or spec sheet may provide additional insights, but practical calibration can yield accurate results. Proper calibration is crucial for obtaining reliable measurements of gravitational acceleration.
bsa09
Messages
1
Reaction score
0
Hello all,
I'm working with an accelerometer to detect movement and I'm using Shimmer IMU. I got values ranging somewhere between 1000 and 2000. My question is, are these values the output of the ADC? And how do i calculate 'g' from the values?
I have attached an xls file with the experiment readings.
Thank you
 

Attachments

Physics news on Phys.org
The device must have some documentation with it. Which should explain what those values are.
 
Probably the easiest way would be to just calibrate it using Earth's gravity - most accelerometers output voltage is linearly proportional to the acceleration, so all you need is two points to calibrate it. If you hold it vertically, such that the measurement axis is aligned with the gravitational force, you can get one such calibration point (9.8 m/s^2), and then you can get the second calibration point by holding it horizontally (0 m/s^2) or upside down (-9.8 m/s^2). You could even do all three, and then do a best fit line to determine a slightly more accurate reading.

Alternatively, there's probably a spec sheet somewhere, but how useful it is will depend on your setup.
 
I do not have a good working knowledge of physics yet. I tried to piece this together but after researching this, I couldn’t figure out the correct laws of physics to combine to develop a formula to answer this question. Ex. 1 - A moving object impacts a static object at a constant velocity. Ex. 2 - A moving object impacts a static object at the same velocity but is accelerating at the moment of impact. Assuming the mass of the objects is the same and the velocity at the moment of impact...

Similar threads

Replies
4
Views
1K
  • · Replies 165 ·
6
Replies
165
Views
10K
  • · Replies 20 ·
Replies
20
Views
3K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 16 ·
Replies
16
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
9
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K
Replies
7
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K