- Body is painted, some detail to finish. Pics forthcoming. Hope you like it :)
- Infrared sensors aren't working as expected, still no idea why
- AHRS (gyro+accel) is only able to track very, very slow heading changes
- I suspect motor magnetic field compass interference more and more...
- If so, compass heading distortion may be proportional to current (and, roughly, speed)
- Added a CMUcam v1 and Arduino serial-to-i2c board to detect red barrels
- Attempted to collect some data when CMUcam approaches red 'barrel'
- Also attempted to collect data on compass vs. speed to test motor field theory
- While trying to collect this data, found that my software is hanging again ARGH!
- While debugging I discovered the CMUcam/Arduino RF interference is killing GPS reception. Double ARGH!
- My power supply has auto cutoff which kicks in with low battery and heavy throttle
- I had a nightmare about the competition. I think it was the Nyquil.
After all this time, I still haven't been able to come up with a satisfactory way to merge compass, gyro/AHRS, and GPS data primarily because the errors in compass and gyro/AHRS are pretty big and obliterate dead reckoning accuracy, and I've spent all this time just trying to understand the nature of the errors.
For the compass/magnetic issues, I'm draining the remainder of my robot funds to try a solution to address the magnetic interference. It's on order, 2-day delivery, to arrive tomorrow. It's a total hail mary play. It probably won't work. Meanwhile, the cheap option is to raise the compass/gps mast... along with the center of gravity.
Raising the mast should also reduce RF interference. Enough? Don't know. I may try to get or make a metal enclosure but there's precious little time for that now.
For obstacle avoidance, a couple of options present themselves. If we know where the barrels will be well in advance of running, I can attempt to plot waypoints around the barrels.
If not, I have a second sonar ranger setup that just came in, enabling the robot to--maybe--localize the barrel.. Or maybe by some miracle I can get the IR rangers working properly.
For navigation, worst case I will run GPS plus some simplistic error correction which I've tested to some degree. If the GPS fix gets too bad (in the urban canyon on the west side of the building), the navigation accuracy will suffer, too.
I may be able to just do some rudimentary logic to get usable heading/position values when the GPS fix gets bad. I'm finding heading is the most crucial aspect of my robot's ability to navigate by dead reckoning. (thanks for that illuminating insight, Captain Obvious...)
I may take a page out of Scott's (Team Tobor's) book and try to use odometry to provide more info on heading.
Whatever merging I do, there's still the GPS lag to deal with.
All of this above, of course, only possible if I can stamp out the latest giant bug very soon.
I've reverted to code from the 5th and it seems to be running. But I've got to re-de-bug all that code now.
But I'm not giving up. Not by a long shot.