Bottoming out on ramps?

[MrForbes]

There are other things you can do, one is to make a ramp that is angled all the way up, with no horizontal part, although you might need some type of brake to keep the robot from rolling back down when power goes off at the buzzer. Or make a teeter-totter ramp, that is angled all the way up and when the robot gets past the tip point, it falls back level.

[flamefixed]

Thanks for all the advice! Any other ideas out there? (Just trying to get a good, well-rounded consensus)

[Brian C]

Don't forget the fact that some teams will be using bumpers and some teams will not.

All else being equal those that eschew bumpers (us included) will have less issues with ramp bottoming than those that use bumpers. There were quite a few teams last year that discovered late in the build that the bumper added a whole new wrinkle when it came to maneuvering up the 30 degree incline.

[MrForbes]

OT:

ok, why is it that when we're talking about ramps, bottoming out, and bumpers, there are two guys with hot rods in their avatars in the discussion?

[Brian C]

HA!

That's 'cause all us hot rod guys like working with mechanical things and robots fill that void during the cold months. I just wish the deuce was really mine........

Seriously, bumpers are sometimes a second thought with teams. The 30 dedgree ramp last year stumped quite a few people. We striving for 20 degrees or less to accomodate the majority.

[rocknthehawk]

OT: I'm going to WyoTech in June for STREET ROD FAB. sweeeet....

[Eric Scheuing]

If you had no problems last year ramping, why not just design a similar drive train?

[Curt Henderson]

Originally Posted by K.Porter

We've designed a 4 wheel drive system which is very much centered at the front of the robot, with the back being supported by casters. That way, even if we do bottom out we will be able to drag ourselves up a ramp with the front wheel drive.

As for our ramp, we have allowed for a shallower angle than last year's playing field, and we hope to round the top corner.

If I understand your idea correctly, it should work if the center of gravity of your robot is balanced over your drive wheels to maintain contact with the top ramp surface. Otherwise you may find yourselves grounded on the ramp with your drive wheels in the air as the CG of your robots shifts to the back wheels when you go up the ramp.

Should this happen, you can always go up the ramp in reverse.

Good Luck!

[Martinez]

This is the number one reason I think ramps are a bad idea. There will be plenty of teams who won't or can't climb a ramp. Its a great thing for most alliances but this really is something you have to design around. I feel that if you are going to come up with a way to lift robots: than it should be universally compatable for as close to everyone as you can, not the other way around. Aside from that, 2" or 15 degress seems rather popular.

[cgredalertcc]

people building ramps need to take into account that other teams aren't building their robots to accomodate ramps. This is the reason 1741 chose to go with a lifting system. My recomendation is if your ramp is greater than 2 inches tall it better have a slope less than 20 degrees, or else no one is getting on.

[DKolberg]

Our ramp will be about 8.5 degrees so everyone should be able to go up it with very little trouble. Robots wider than 40" need not apply. See you at the tournaments.

Dave

[Elpants]

Our bot completely folds up to 13" tall 26" wide and 37" long arm and all enclosed.

With the smaller wheels this year most teams I suspect will have a lower ground clearence. I was playing around on a white board with scale drawings to see the best kind of angle our ramp should be. As it is right now our own bot (with a ground clearence of 2 3/8" cannot even make it up our own ramp that I have drawn up for inventor with-out high centering on the corner..

Our deadline for a working chassis with arm is to be finished tomorrow, all our programming was getting finished up last night. So I need a general average of ground clearence so I can design our to accomidate the average team. (That, or I hope a lot of teams have 6wd/treads )

[1768]

Originally Posted by Scott358

In the end, regardless of how you do it (ground clearance, skid pad, 6 wheel drive, etc...), you definately want to keep ramp climbing in mind (assuming you're not the ramp!).

Given the abundance of ramps, keep ramp climbing in mind even if you ARE the ramp. e expect to be on at least one team where the entire team is ramp-bots, so we are designing to climb a ramp and be a ramp low-clearance bots can climb.

[MrForbes]

Originally Posted by Elpants

Our bot completely folds up to 13" tall 26" wide and 37" long arm and all enclosed.

Have you considered the implications of rule <G29> on the starting configuration of this design?

[Elpants]

Originally Posted by squirrel

Have you considered the implications of rule <G29> on the starting configuration of this design?

I guess I should be more specific, this is w/o a ramp and all electronics and drivetrain within these dimentions, just stating that with a plateform height of 13" its getting hard to create a ramp that is under 4' tall and wont have a problem for our own bot to get up w/o getting a running start.

our height changes, at the end of the game, the robot is 13"tall.