48 Bump Teaser

[Travis Hoffman]

http://www.youtube.com/watch?v=MxvgNO6V5Lc

Stop me if you've seen this all before....

Extended version, replete with bad driving and extra nagging:

http://www.youtube.com/watch?v=JXkK4WVsJAk

[dtengineering]

Lookin' good!

But what's with this "slower... slower" stuff? You can't "get air" by going slower!

Or am I kind of missing the point here....?

Are those omnis on the outside ends? It seems to me that high traction wheels in that arrangement might make turning difficult, but it doesn't seem to be a problem for you.

Jason

[Travis Hoffman]

Originally Posted by dtengineering

Lookin' good!

....

Are those omnis on the outside ends? It seems to me that high traction wheels in that arrangement might make turning difficult, but it doesn't seem to be a problem for you.

Jason

The robot currently has dualie aluminum omnis on the one end and plaction wheels everywhere else.

Turning is satisfactory but could be improved with a tweak to the gearing.

[camtunkpa]

I'm with Gary on the slower slower business . Looks good 48. Good Luck!

[Alex Cormier]

"I wanna go fast... I wanna go fast..."

[Travis Hoffman]

Originally Posted by Alex Cormier

"I wanna go fast... I wanna go fast..."

In 2001, you might remember the infernal see-saw in the middle of the field. We were on this thing once, ahead of a partner. We were rushing to get over it (it was our best match of the year, with Wildstang at Epcot), but the partner behind us made the see-saw tip over more slowly. Instead of gently hitting the ground with the thing fully transitioned, we drove off the front with the saw's lip a good number of inches still in the air. We subsequently landed very hard and cracked our front frame, necessitating a lengthy pit repair.

Transitioning over the bump at a high rate of speed successfully simulates that 2001 situation. Our first system test isn't the place to unleash a turbo boost.

[Racer26]

Travis,

Is 48 planning on going to Atlanta this year? 48's gone to CMP every year since their inception. I assume the 2010 FRC Championship isnt listed on your team's list because you didnt get in on the waiting list and have to get in on merit with an RCA or Regional Champion?

If so, I can't wait to see xtremachen (11 is it?) in action there, otherwise, it seems I'll have to wait until KKXI since 48 isnt coming to any of our Canadian regionals.

[Travis Hoffman]

Originally Posted by 1075guy

Travis,

Is 48 planning on going to Atlanta this year? 48's gone to CMP every year since their inception. I assume the 2010 FRC Championship isnt listed on your team's list because you didnt get in on the waiting list and have to get in on merit with an RCA or Regional Champion?

We were invited off the waitlist but decided to decline. Budget savings, among other things. We may have access to additional funding if we qualify.

If so, I can't wait to see xtremachen (11 is it?)...

13

...[ in action there, otherwise, it seems I'll have to wait until KKXI since 48 isnt coming to any of our Canadian regionals.

We certainly put our time in up there. Not attending Canadian regionals seems to be an unfortunate trend among American teams. They don't know what they are missing.

[Racer26]

Well, I hope 48 qualifies and we get to see you in Atlanta, otherwise, I'll be watching from the webcasts, and see you in Flint come September.

[Joe Johnson]

Nice. Thanks for sharing.

Just another contrarian note for all these pivoting truck designs (this in NOT a criticism of team 48's design or any of the other similar designs we've seen -- you've implemented a very cool feature. Hats off to you. BUT...) You guys do realize that your tipping wheel base is the distance between the pivots of your trucks and not the distance between the first and last wheel, right?

I know you can do things to make this not be the case (have the truck axle lock up, implement a wheelie bar, etc.), but so far, all the pivoting truck designs I've seen have no obvious means of accomplishing that task.

If it comes to a pushing match with two robots, each with great traction, one with straight NWD and another with a pivoting truck design, it seems to me that that smart money will bet on the NWD machine tipping the other (or rather, the pivoting truck robot will have to call off the fight rather than continue to push and tip itself).

I'm just saying...

Joe J.

[Travis Hoffman]

"Wheelie bar" makes me think of climbing the ramp with this robot in 2003. We actually need to add an obstruction in the back of the robot to keep balls out ....we could always make it more functional.

Since early in the build, we've been considering some kind of tensioning of the drive pods - anything from active cylinders to gas springs to pre-tensioned surgical tubing. We expect to do more testing and decide upon a final solution, if needed.

We do also have mechanical travel hard stops on each pod (backed up by the drive chain which will mesh nicely with the plaction wheel roughtop if the hard stops fail - ha) - it remains to be seen how they affect "tippability".

Thanks for bringing up this concern.

[JamesCH95]

Originally Posted by Travis Hoffman

In 2001, you might remember the infernal see-saw in the middle of the field. We were on this thing once, ahead of a partner. We were rushing to get over it (it was our best match of the year, with Wildstang at Epcot), but the partner behind us made the see-saw tip over more slowly. Instead of gently hitting the ground with the thing fully transitioned, we drove off the front with the saw's lip a good number of inches still in the air. We subsequently landed very hard and cracked our front frame, necessitating a lengthy pit repair.

Transitioning over the bump at a high rate of speed successfully simulates that 2001 situation. Our first system test isn't the place to unleash a turbo boost.

We did the same thing, only we bent a drive axle in a final round match! It miraculously got replaced in less than 5 minutes for the next round, but from then on we started using 1/2" steel axles.