Determine position given linear and angular accelerations

AI Thread Summary
To determine the position of a body in an inertial frame using linear and angular accelerations, the discussion emphasizes the need to integrate these accelerations over time, starting from the origin. The user currently uses a basic method of integrating linear velocity but seeks a more accurate approach. They consider using the body frame's velocity and rotation data, applying the Euler (3-2-1) direct cosine matrix to convert the velocity vector to the inertial frame. This method is questioned for its validity, particularly regarding the transformation of the body velocity vector into the inertial frame. Overall, the discussion revolves around improving position calculations through better integration techniques and frame transformations.
JesseGeisbert
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Hello,

I would like to know how to calculate (x,y,z) in the inertial frame at any given time, t for a body I am testing. On the body, I have one instrument that can give me (u,v,w) in the body frame, another instrument to give (roll, pitch, yaw) in the body frame, and yet another instrument that can give both linear and angular accelerations (again in the body frame).

I am sampling at 100 Hz, but I want to determine position in the inertial frame from t=0 until the end of the test spot. I am assuming at t = 0 that the body is starting from the origin (0,0,0). At each new time step (i.e. t = t0 + 0.01) I get another data packet containing the information listed above.

Currently, we do a very crude method for determining position by integrating the linear velocity vector over the time step, but I'd like to improve upon this by starting with the linear and angular acceleration vector and integrate to get position.

Any help is greatly appreciated, thanks!
 
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While continuing to try to solve this problem, I was wondering instead if I should use my velocity and rotation relative to the body frame (u, v, w) and (roll, pitch, yaw) and translate the velocity frame back to the inertial frame using the Euler (3-2-1) direct cosine matrix?

Is this approach valid? If I apply the 3-2-1 direct cosine matrix, and multiple that by my velocity vector, doesn't this put my body velocity vector into the inertial frame?
 
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