Team 980 Thunder Bot's "Jaws"

[David Brinza]

With a bin in its jaws ready for stacking, the Thunder Bot is pushing more bins into scoring position.

[yangotang]

not bad. the only thing i'd say is that if the placement of the box isn't level, would it cause the stack to be not level?

[DougHogg]

Originally posted by yangotang
not bad. the only thing i'd say is that if the placement of the box isn't level, would it cause the stack to be not level?

I think that our driver picked up the bin from the top of the ramp. Since our robot was on a slant, the bin wound up somewhat slanted in the jaws. However, when we put the bin down, it settled down nicely.

Our real claim to fame is the telescoping arm attached to the top. It can rotate 360 degrees, and can be raised up to any height. When fully extended, it is quite impressive.

[Jnadke]

That drive system is prety neat...


Two sets of wheels, each a different diameter. Makes it kinda like a transmission, only easier. Do you have both sets of wheels engaged together or separately? I can see slight problems if you try moving when both sets are down...

I see the levers in the middle to change the wheels... are those motor driven or pneumatic driven?

Engaging them separately wouldn't be a whole lot harder than together... just use gears instead of sprockets/chains. Though, you'd need a coupler between the gearbox and wheels to handle the shock...


For those that have no clue what I'm talking about... see how the small wheels are touching the ground, and the big one's are up in the air? It's kinda like a "poor man's transmission". Both wheels spin at the same speed, but since one has a larger circumference, it will cover a greater distance than the smaller one's. Therefore, they can engage either wheel and have a 2 speed robot. The other wheels will just spin freely. Very little power will be lost because of very little friction.



Hmmm..... this gives me a few ideas.... with the right gears, you could do the same set-up such that when both sets are down, they have high-torque, high-traction (even though the diameter of the wheels are different, rotate them at the same speed). Then, when the larger wheel is "down", it actually engages the gear of the smaller wheel, producing a higher-speed.

That'd be quite a feat, but it'd be pretty neat to see. When the faster speed is engaged it would look something like an I-Bot but with a large wheel on the bottom...

[David Brinza]

The wheels are shifted pneumatically. Both sets of wheels are always engaged to the drive train. There are different turn ratios for the big/small wheels (independent chain drives for each set).

The drive system shifts remarkably smoothly, even when we are under the load of another robot pushing.

I'll post a picture later that shows the drive train in a bit more detail.