pic: Drivetrain Concept

[Aren Siekmeier]

Originally Posted by Hawiian Cadder

right, but their driver was able to sort of drift, which made it one of the fastest robots in turning around to place tubes.

Yeah, like a power slide.

[Andrew Remmers]

If I'm not mistaken couldn't this also be a 4 speed shifter?

With the two ratios on the gearbox than then the two different ratios given on the wheel sizes and reductions (don't know if they are synced)....

Thats. Insane. I like it!

- Andrew

[crazyStone]

Just realized there was a mistake in the design concerning which Supershifter drove which side. A redesign is nessecary and taking place and should clear up some of the issues of the 2 transmissions. We are now attempting to link both front modules to one supershifter and both back modules to the other. Instead of the linking front and back on each side like it is now.

[lemiant]

Originally Posted by crazyStone

Just realized there was a mistake in the design concerning which Supershifter drove which side. A redesign is nessecary and taking place and should clear up some of the issues of the 2 transmissions. We are now attempting to link both front modules to one supershifter and both back modules to the other. Instead of the linking front and back on each side like it is now.

If I understand this right you're switching from this linkage:

<front>
o o
| |
o o

to this:

<front>
o-o

o-o

If that is the case you won't be able to turn.

[crazyStone]

good point which represents the reasoning behind having 4 gearboxes. You limit mobility if you restrict the ways you can turn if you link front and back together.

[Aren Siekmeier]

I don't get it. You obviously can't have both front wheels and both back wheels together, because both sides are always doing the same thing, and you therefore can't turn. Also, if you try to make the front wheels do something different from the back wheels, you will just shred your tread (at best).

You CAN however have each side on one gearbox, and as already stated many times, there's no reason not to. Standard tank turning is accomplished by running each side at different speeds (or even different directions).

[crazyStone]

yes it can be done and its a good approach and it is our fallback, but if you want to run traction in back and omni in front you can't have different ratios because the wheel size is different whereas if the the gearboxes are seperated the speeds themselves can be altered and allow for the two different wheel sizes to work together.

[PAR_WIG1350]

Originally Posted by crazyStone

yes it can be done and its a good approach and it is our fallback, but if you want to run traction in back and omni in front you can't have different ratios because the wheel size is different whereas if the the gearboxes are seperated the speeds themselves can be altered and allow for the two different wheel sizes to work together.

You can accommodate different wheel sizes driven off of the same gearbox by gearing the wheels at a ratio (to each other) equivalent to the ratios of the wheel sizes. For example, if you have a 4inch and an 8 inch wheel driven off of the same gearbox, by having a 1:1 sprocket ratio between the output and the 4 inch wheel and a 2:1 ratio between the output and the 8 inch wheel they will run at the same ground speed. It is usually lighter to uses different sprockets to accommodate the wheel size difference than to use different gearboxes for the different wheels.