Advice needed !!

[Francis-134]

Did you lower the center wheels of your robot? Most 6-wheel designs include a dropped center wheel to facilitate turning (the robot is never on more than 4 wheels and will turn on the center two).

Another no-brainer check is to make sure that you have 40A breakers and not 20 or 30A breakers pluged in line with the motors.

Also, make sure that your gearboxes are properly lubricated and that there is as little resisitance in them as possible. That's all I can think of right now: Good luck!

[Cory]

Make sure you have a backup battery plugged into your robot. We've had issues at home during practice, when we forget the backup battery.

[Frenchie]

If you're robot is trying to brute turn a six wheel traction drive... you're going to be killing your motors in no time!

With a six wheel drive, the common thing to do is to lower the central wheel by a tiny amount (1/8" for example) in order for the robot to turn with more ease. Other solutions involve switching some of the wheels to omnis or casters (the advantage of omni there is that you can power them to push forward and not completely lose the 6WD traction advantage). What I've also seen done is powered caster system that drops down every time the robot tries to turn.

If you have taken provision to make your robot turn easily, then it would seem to be an electrical problem (the "drive forward" code is straightforward enough that it is unlikely that there are any mistakes there). Recheck all PMW connections and make a continuity check with the frame to find a possible leak. As said, you should also make sure you have the right breakers in!

Good luck!

Francois

[dtengineering]

Try putting omnis on the "heavy" end of your robot. We found that with 6" IFI traction wheels on our six wheel drive "Aim High" bot, and two CIMs PER SIDE, that we had trouble turning even with lowered centre wheels. We put on a couple omnis, gave up a wee tiny bit of traction and gained a whole lot of mobility.

And Martin... you guys were only running one CIM per side? Wow. We couldn't tell from watching in Portland. Guess a great machine doesn't need a killer torquey drive train after all!

Jason

[854 bears]

we have lowered our center center wheels by i beleive a 1/4" so the turning is very easy. We have made sure the backup battery is in and that there are 40amp breakers installed for the drive vistors.

In waterloo we replaced the traction material on the front and back wheels with strips of lexan to greatly reduce the friction. Although we are still having this problem.

Thank you for all your help and we will be sure to check all of our connections over this comming week in toronto.

[VEN]

Check your CIMs, I spent half an hour replacing one of ours because it was dragging down the whole drive (we have 6 wheel drive, 4 cims in total, middle wheel 1/8" lowered, and custom 12:1 gearboxes)

[=Martin=Taylor=]

Originally Posted by dtengineering

And Martin... you guys were only running one CIM per side? Wow. We couldn't tell from watching in Portland. Guess a great machine doesn't need a killer torquey drive train after all!
Jason

Maybe you didn't, but lots of other teams did. Lots of people told us that we looked slow and wondered why we weren't driving faster.

We are considering adding two of the FP motors to the drive for Atlanta to improve our acceleration. However, we will need to lose an additional 4 lbs. to make weight for this...