pic: off season chassis

[jsasaki]

loading photo ...

[JVN]

This is very intriguing to me. I'm assuming the middle (omni) wheel is offset lower than the traction wheels. This would mean the chassis is always sitting on 2-traction wheels + 2-omni wheels at any given time.

The weird thing is... I imagine the turning point of the robot would drastically shift from the front to the back depending on which set of wheels the robot is sitting on. (At least, this is what physics tells me).

Have you driven it yet? How does it handle?

Is there a reason you didn't go with front/read omnis and middle traction wheels? This would result in the same 2+2 configuration, but you'd have a consistent (centered) turning point.

-John

[nighterfighter]

Silly John...

That IS the whole chassis!

The game this year is obviously going to be a scooter-like thing!

[Mr_I]

I tend to agree with JVN's comments, with this addition: Seems to me that by putting the omni's in the middle (presumably dropped the obligatory 1/8"), you lose your resistance to sideways pushes.

[ttldomination]

And are we looking at the outer part of the chassis? I see two sprockets on the middle wheel and one sprocket on each outer wheel, so I'm wondering where the motor goes...

[akoscielski3]

Is it realy strong, i would like to do something like this because our normal chassis is extremely heavy, but strong

[MattC9]

I'm guessing the center wheel IS DROPPED so it will function as a normal 6WD chassis. This is so because we all know on most 6WD there are only 4 wheels on the ground so it can rock and turn? right? so the middle wheels act as the turning point so its like a 4WD with omni's in front.
Do i make sense? Because it was a little hard to explain trough the 'net

[s_forbes]

If the CG is fairly balanced front to back I don't think the traction wheels would get enough grip to greatly affect how the robot turns in place. I suspect you could probably pull some of those fun maneuvers from Lunacy though, like the sideways slides and the backwards-180-forwards whip around. Looks like fun to play with!

[jsasaki]

This is great I put this up to see what kind of comments i would get .. to clarify things up... we can swap all 3 wheels and I think we were also looking at going for all 6 wheels to be plaction style wheels. we are going to run it on friday soooo we'll see

[JVN]

Originally Posted by jsasaki

This is great I put this up to see what kind of comments i would get .. to clarify things up... we can swap all 3 wheels and I think we were also looking at going for all 6 wheels to be plaction style wheels. we are going to run it on friday soooo we'll see

Jun,
Try it in the configuration shown! If nothing else I'm extremely curious how it performs. I don't know if it will perform well (in fact I suspect it won't)... but you'd be my hero if you tried it out and took some video...

I bet if nothing else you could teach some students a cool lesson on drivetrain turning (the video would also be giving me a tool I could use to teach the same things).

-John

[Chris is me]

I think this is really cool. Imagine a robot that could shift its CG at will by moving an arm or a weight. You could pivot among whichever axis you chose, if for whatever reason you didn't want to rotate about your center.

[theprgramerdude]

The middle wheel will simply make it so only a front set and middle set or back set and middle set are on the ground at a time. Thus, it's treated like any four wheel drive, except the issue with this 4 wheel drive will be that half of the mass is located beyond the sliding wheel. It certainly appears that resistance to rotation from robot-to-robot contact will be reduced, but this may be intentional (It's an interesting concept that could be explored, IMO).