Anyone have any experience running the KOP wheels on asphalt for an extended period of time. We have a parade coming up. Thanks
Not a good idea, they get really black and scratched up, and basically ruins the wheels. I would swap in some Andymark rubber traction wheels from years past, there basically the samething with rubber treads.
If you’re doing a parade I’d very much recommend that you put your robot on a cart. Will your battery really last for an “extended period of time” if you’re driving the bot down several city blocks? This way you don’t need to modify the robot.
We do it every year. We swap out batteries twice and run the OI from a battery. I think we need to swap the wheels.
You did it every year - with the old control system. You may need to be careful about making any assumptions about the battery lifetime and total traverse distance with the new system. Unless I had run a few tests to understand the effects of the new control system on battery life when attempting extended driving, I would want to be rather cautious.
-dave
** although, this does cause one to think about a great idea for an alternate off-season competition - having a competition to see who can drive the longest / farthest with their official FRC robot on a single battery charge. How many laps can you do around an official 1/4-mile running track with one battery? What can you do to your drivetrains to make them as power-efficient as possible for this test (rather than as fast or as powerful as possible)? Given all the recent interest in “green” projects, this could be kind of interesting.
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Point Taken
/2010gamehint
I would seriously recommend against using '09 wheels, your robot may hop all over the place due to rocks, etc. Andymark kit wheels from years past would do the trick.
We drove our robot for about 3 hours not stop last week Thursday at a demo on one battery. Granted we don’t have lot on our robot that sucks power, like the compressor. We just drove around and shot/dumped balls on the floor. So i think you could probably run your parade but i don’t know what your robot all entails this year.
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http://www.cef-trek.org/Home.html might be of some interest then. I know that Pontiac Northern High School has a team (there are others around here I just don’t know anyone on them) It forces you to take into consideration a lot more real world engineering than you do in FRC. Just an interesting experience.
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careful on what drive you have. We have a 4 wheel independent steering, and it really didn’t like switching to rubber wheels, but they are the same size and won’t get damage.
The DS at least runs for 3 hours on a vex 1000mAh 9.6v battery. Using an Exide 12v competition battery lasts practically forever.
No problems with parades there.
our wheels are doing fine, but our bearings are breaking. For the past 4 years we’ve been completely fine with our 6 wheel drive, but this year, we’ve had 5 bearings out of 16 break, and we expect the rest to continue break, we believe its due to the ridged forces from wheel on FRP. We saw it also happen with our sister team who uses identical bearings.
That’s kind of what we did BEFORE getting tied up in this robot stuff… this youtube video starts with our electrathon car (in blue), doing hot laps on the Vancouver Indy track with the camera mounted on the car built by our good friends and neighbours from Gladstone Secondary (well known in the FTC world last year and VRC world this year). It then goes on to some footage from other races around the Vancouver area.
The cars run on a 1hp DC motor running at 24 volts from two 40amp-hour deep cycle gel cells. The race was one hour long (including two driver changes) and… in our high school category, you needed to go around 40 km to win, depending on the track and driving conditions. Peak speeds were in excess of 50km/h, which doesn’t sound that fast until your butt is three inches off the ground on a tricycle with no suspension held together by student welding. Okay… the teachers inspected the welds, especially on the safety cage… we weren’t INSANE… it just felt like it. If you look up some of the “open” class racers, 80km+ is quite doable with a similar set up. I think there are a few of the Hawaii FRC schools who compete at a fairly high level in Electrathon… there must be others, too.
HOWEVER… this sort of concept COULD be applied to FRC. Teams could be limited to two (or three, or whatever) competition batteries, to be stored on the playing field at the beginning of the competition, and returned to the battery storage facility after each match. Teams would choose which battery they wanted to use for which match, and teams qualifying for elimination rounds would be allowed one (or two) additional fully-charged battery.
Power management would become a huge part of the competition… do you REALLY want to burn amps in a pushing match in the first qualifying round? Do you REALLY need to keep your intake rollers running ALL the time, or do you build sensors so they only come on when needed? Do you REALLY want a 150 pound machine, or would you rather build a 100 lb machine? And maybe you’d rather run the pneumatic system at 60 psi rather than 120?
How do you optimize the efficiency of your machine so that you can play hard at the beginning of qualifying, but not drain your power supplies for the last matches… and in elims… if you burn amps to win in the quarters, will it come back to haunt you in the finals? How do you keep track of which battery to use next?
Oh my goodness… this *would *be an interesting switch-up. Even more interesting than the low-friction surface this year.
Jason
Out of curiosity…what bearings are you using?
What do you mean by “breaking”?