Thread: Accelerometers and speed
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Unread 16-01-2014, 15:09
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Re: Accelerometers and speed
Quote:
Originally Posted by Joe Ross View Post
While this is theoretically possible, in the real world, with cheap accelerometers, it isn't practical. Small errors in acceleration add up over time and produce poor velocities and even worse distances.

A similar process is used for the gyro (which gives angular rate) and to get angle. The cRIO FPGA does the calculation at a very high rate (1000s of samples per second), which wouldn't be possible in software. Even so, the gyro angle drifts by many degrees by the end of a match.

It's possible that you might get decent velocity results for a short period. If you wanted to experiment with this, I would look at how the gyro software was implemented and copy that.
I always thought the drift of a gyro was predictable and you could correct the drift in code.