GY-521 to measure velocity of swinging door

Using Arduino Programming Questions
#1

Hi,

I wanted to measure the linear velocity of a swinging door with the GY-521(3 accel, 3gyro) sensor attached to the door (for example a car door). I have been reading about this topic but have not received any concrete information so far. My questions are two-fold:

  1. How to calculate the linear velocity of a swinging door in Arduino?
  2. Will, in this case, the accel/gyro data be enough to track velocity accurately? I know the errors stack up if the sensor is moving in 3D space.

Thank you.

#2

Will, in this case, the accel/gyro data be enough to track velocity accurately?

Not the accelerometer. Read about why not at http://www.chrobotics.com/library/accel-position-velocity

The gyro measures the rate of rotation, which is the relevant quantity. Try it and let us know.

#3

All points on the door have the same ANGULAR velocity. What part of the door are you trying to find the linear velocity of?

#4