Quote:
Originally posted by Andrew
For those of you who have used the gyro on FIRST robots, how much of a limitation is 75 degrees per second? Have you seen your robot exceed that value?
I would think that the errors introduced by scaling the value between 0...255 would introduce more overall error in the integration than the robot turning faster than 75 dps.
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For the first question: Our robot typically turns at around 180 degrees per second. Due to this, the 75 degree/sec GyroChip is pretty much useless to us. If you want to use it for a different application, this limitation might not be a problem. You should also have some margin for unexpected occurances. For instance, our robot can turn at 180 deg/sec on its own, but when we get hit by another robot, it might be able to turn much faster. Therefore, the 300 deg/sec part gives us a little margin.
For the second part: Quantization of the signal (using 256 discrete values instead of infinitely many values of an analog signal) is not that much of a problem, especially if you have enough random noise with peaks above 1 A/D count. This will also be less of a problem with the new PIC micro since it has a 10-bit A/D (1024 discrete values, instead of 256 with the 8-bit A/D).
Random noise at the A/D can improve the apparent resolution of your A/D converter. This could actually be an entire whitepaper. If there is enough interest, I'll try and find time to write it up.