Understanding of variables and units

ArduCopter
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1

Hi Community,

I’ve got an issue with the correct understanding of used variables like ACC1, GYR1, CURR, BARO, ATT and so on. With the help of this forum and other external sources I managed to have a glimpse understanding of what kind of information is logged with the specific variables like this easy example CURR_Curr or a more sophisticated like ATT_Pitch.

But now I am confused with ACC1 and IMU_Acc, which when I understand correctly, does the following:

  • ACC1_AccX = raw x-accelerometer value of IMU, logged in 1000Hz
  • IMU_AccX = down-sampled x-accelerometer value of IMU, logged in 50Hz

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What I don’t get, why are the absolute values for the magnitude so different? For ACC1_AccX the amplitude is between 35 and -50 and for IMU_AccX just -3 and 5. Even though can someone please give me the proper units? I guess for IMU_AccX it is m/s². What is it for ACC1?

Thank you for your help
Phreet