Angle measurement for balancing robot.

[Darrel Taylor]

Hi Henrik,

Just wondering if you used your new PID "Code Example" on the Balancing Robot?
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[HenrikOlsson]

Hi Darrel,
Yes I did. The robot was the reason I wrote it. It a 18F2431 for each wheel running a PID compensated velocity servo at 1220Hz thanks to your interrupt routine. The main CPU runs the PID for the actual balancing at 100Hz.

Any chance you see some way to improove it?

/Henrik Olsson.

[Darrel Taylor]

>> Any chance you see some way to improove it?

Actually, yeah, I've got a couple ideas. I'll post them in the other thread.

But, back to the Balancing Act.
Did you use it in place of the Kalman filter, or with it?

Just curious.

[HenrikOlsson]

Hi Darrel,
Nope, the Kalman filter (if I ever understand/get that to work) would be used only to track the absolute angle of the robot platform. (Basicly removing the gyro drift). The error (desired angle - actual angle) is then fed to the PID-filter which in turn tells the motor-driver how fast the wheels needs to spin to keep it upright (or whatever).

As it stands at the moment (with the SHARP sensors) it just subtract the front sensor reading from the rear sensor reading and sends that value the PID-filter.

Thanks

/Henrik Olsson.

[uffi]

For those of you interested, I put here the link to my internet homepage, where you can find videos and description of my two-wheel balancing robot named ARTIST.

http://home.arcor.de/uffmann/ARTIST.htm

Have fun, Dirk.

[bbarney]

don't know if this is the answer but check it out
http://www.austriamicrosystems.com/0...ons_AS5043.htm

[HenrikOlsson]

Hi,
Thanks! Unfortunatly it won't work. That sensor outputs a value based on how a magnet placed in front of the sensor is rotated.

/Henrik Olsson.

[bbarney]

I just ran across it by mistake and remembered your post and thought maybe it would work,some interesting stuff there though