Quote:
Originally posted by KenWittlief
a simple way to solve the gyro 'zero' problem, when you first start auton mode, read the gyro and see what its putting out. Since the bot is not moving, THAT is your zero reading.
|
With 6 motors drive, and three other feedback systems, and the autonomous mode variables, the number of spare variables available got pretty limited. I set the gyro iniatial value as a program constant, and got reasonably consistent turning results. It was during driving that we had trouble, which turned out to be 'wheels not mounted perpendicular to the side of the robot' problems, but this was not apparent until after we'd tossed out using the gyro, and gone to much more reliable (with straight wheels) timed turning.
On the other hand, since the gyro seems stable enough when not moving, the op-amp solution could be set-it-and-forget-it. It requires no programming space, outside of accumulating turn rate info. You could do that with a (really) low leakage integrator. If you made the output voltage range 127+/- 90 counts, each count = 2 degrees, and you'd have turn rate if you needed it, or heading data right there. Rollover at 0 or 360 would require some relay work,,,
Note that Systron Donner's webpage offers big boxes with 3 axis turn rates and accelerometers - the complete inertial nav system. But they probably do it digitally to make reprogramming easy, in the meagabytes of fast, powerful computing space they use.
