Two-Speed Chassis

[Wetzel]

I saw a robot that did this at the SoCal regional last year, but I do not recall the team number.

What is the height of the crossmember when raised? How much is the base raised when in highspeed mode? It appears from the images that it isn't that high with plenty of room around it to place things.

However, it does appear to severly limit placement of manipulators low to the ground, which has traditionaly been part of the game in some way.

Pretty.

Wetzel
~~~~~~~~~~~
Hurray for shared innovation.

[JVN]

Originally Posted by Wetzel

I saw a robot that did this at the SoCal regional last year, but I do not recall the team number.

That would be 980.
Saw them at IRI.
Heck of a bot.

[Tristan Lall]

In terms of actually transferring power to the two sets of drive wheels, are you going to be driving the low-speed wheels directly from the gearboxes, and then running chains to the high speed wheels? (No driveshafts appear in the drawings.)
Are you going to have enough room to run sprockets and chain (with any necessary ratio) inside the pivoting triangular frames (the red parts with wheels attached)?
Also, both sets--front and back--of low-speed wheels need to be powered. Does this imply that you'll be running a drive chain inside of the C-channel, from shaft to shaft? If so, it looks like you'll be limited to relatively small sprockets (max 2" to 2.5"), which, as we found out last year, can eat chain, given a powerful drive system....
With what appears to be 1/8" plate in the centre of the chassis, are you concerned at all about flexing/buckling (due to collisions, or the 200-lb pneumatic fury of those pistons)? A crossmember of some sort would surely minimize this. (Maybe that was going to be added later, in the final version of the design?)
Lastly, will those 1/2" rods that support the entire wheel assembly on both sides be enough to handle the stresses of driving? If the field is flat, you might be just fine, but with something like last year's ramp, they may prove insufficient for the bumpy ride that the robot might endure. (The bolt holes in the C-channel where these attach are going to be rather stressed if the robot falls even a few inches.)
OK, that's enough constructive criticism for now...otherwise, though, it is really quite an interesting design. (And very nicely executed.)

[Madison]

I appreciate everyone's feedback so far. I promise to answer all the questions you've asked as soon as I can. I think I need to do some math again since I can't find the calculations I did for output speed and output torque, particularly.

Thanks!

[Raul]

Nice design.

Might I suggest that two of the omniwheels (on one end) be changed to regular high friction material. This will give you much more control. With four omniwheels, it can slide around too easily, especially if it gets bumped.

Raul