Re: Macanum ability to climb ramps
 

Team 1058 took our old 2007 drive system(pictures posted here somethere) and stipped it down, to just wheels and frame, we tehn flipped it over, making moree frame clearance, and we were able to almost get over the ramp (most of the time). This was a quick prototype (we spent about 2 hours modding it (wheels had to be reverse after we flipped it, new cotrol system ect)), but with some extra elevation on the frame (maybe like 3 inches) we will be able to get ovet the hump with no issue.

Re: Macanum ability to climb ramps
 

We were able to get the 6 inch up the ramp and the 8 inch walks over it. If anybody looks closely they would see our video of the 6 inch going over the 45 degree ramp. No problem at all.

Re: Macanum ability to climb ramps
 

so basically,
everyone is saying that in order to effectively climb the ramps using mecanum wheels, you need to either have 6 wheels or have your robot be able to bend in half ?

also, i have been searching to see if there are any mecanum wheels that have tread on them and i haven't found any. is it possible to buy these or am i looking for something non-existent ? :P

Re: Macanum ability to climb ramps
 

Mecanum drives with a lot more traction then they have now could have issues with breakers tripping and whatnot. Power draw gets pretty big.

Re: Macanum ability to climb ramps
 

Our (modified) 2008 robot (with Mecanum) mostly made it up and over the ramp. I say mostly, as we had to compensate for a high CG. But I think it worked...mostly.

Re: Macanum ability to climb ramps
 

Video: http://www.youtube.com/watch?v=jQMcw4QNCLI

Re: Macanum ability to climb ramps
 

That picture there shows a frame that wouldn't flex at all. That is, unless you incorporated some sort of sliding mechanism. I can't spot anything like that in the drawing.

Re: Macanum ability to climb ramps
 

As it is now, that robot in the video would violate <R11>, but I'm assuming you're planning on adding a fixed frame perimeter as shown in the picture? That looks like a very good design to me. Though as the above poster said, you'd have to allow some sliding at those pivot points. And when it is on flat ground, all the wheels would line up, leaving the bumpers 10" off the ground.

Re: Macanum ability to climb ramps
 

That might be a question for the GDC... Couldn't it be argued that an articulating robot inside a static frame is basically an articulating frame on a static robot? (That is to say, if your bumpers are changing height with respect to the rest of the robot while you're on the ramp, aren't they articulating and thus illegal?)

Re: Macanum ability to climb ramps
 

I check the movement of a standard frame against our robot desing and ours actually moves 1/2 in less. The rule is inffect when the robots are on the flat ground and our passes that test on flat ground ( all robots bumpers move up and down going over the ramp).

Re: Macanum ability to climb ramps
 

OK Proof of concept video... Yes Mecanums can negotiate the bump...we used 8" mwcanums. See?

http://www.youtube.com/watch?v=UQQ67SB8Acc


Steve

Re: Macanum ability to climb ramps
 

Nice...:) It goes over with out effert. How does it do at high speed???

Re: Macanum ability to climb ramps
 

Haven't run it at full speed yet, but I predict a good 8 FPS at least. Our programmers hadn't finished but we wanted to end the day with progress. We'll have it running full speed tomorrow.

Steve

Re: Macanum ability to climb ramps
 

How does it do with weight? If you placed/mount plate weights or something of that nature on your frame, does it still climb efficiently? I'd like to know because we're considering something similar but don't have the wheels in hand to play with yet.

Re: Macanum ability to climb ramps
 

This configuration works best when you are at a right angle to the bump.
OK Speed. I think it is pretty decent. Perhaps not the fastest bot out there but fast enough to compete and still be controllable.

http://www.youtube.com/watch?v=pD2tsY8JKa8


Good point. everything is just strapped together right now, so we havn't weighed it down, I think we have enough spare push for a completely loaded robot. I'll post when we get to that point.