Re: Prototype Small Wheeled Shooter
 

This seems like it would be true. The initial prototype design came about for the design requirement of being able to mount our shooter/collector on a lift so it had to be insanely small and light. I'm glad other teams have found a use for it but our specs were never meant to be taken as optimal for all situations. In fact we only ever plan to shoot from behind the pyramid as our max distance, most of our shots should only travel about 4 feet total before entering the goal.

Re: Prototype Small Wheeled Shooter
 

Thank you very much about this post, we use a small wheeled shooter too now, and it can shoot up to 40 fit ( 2 bag cims, no gears )!
you helped us alot! :)

Re: Prototype Small Wheeled Shooter
 

What compression, wheels, and wheel separation are you using?

Re: Prototype Small Wheeled Shooter
 

every wheel uses one bag motor with no gear, and i dont realy sure about the wheels, i never saw any wheels like them, they made of some kind of spong .. here's a picture we got in fb, it doesnt explain alot, but still..
http://www.facebook.com/photo.php?fb...type=1&theater

Re: Prototype Small Wheeled Shooter
 

Something or another like this? Our team used a similar product back in 2010 for our ball magnet. Worked great.

Re: Prototype Small Wheeled Shooter
 

Because of the buggy BAG motor problem, we have switched our motors over to a BB775 at 3:1 for the first shooter, and a AM-9012 1:1 for the second wheel. The first wheel is at 90% power while the second is at 85%.

We are shooting the high goal from the back of the pyramid with ease so we are pleased with the result.

We also made the compression on the first wheel about 3/16 less than the first wheel to aid in our ground loading. This change did not effect distance at all.

Re: Prototype Small Wheeled Shooter
 

While this post is regarding using the VersaPlanetaries with a pneumatic wheel, I figured I would post it here after all the other postings about powering shooter wheels off of the VersaPlanetary.

My team's competition robot is currently running a two 8" pneumatic wheel linear shooter directly driven by CIM motors that were attached to a machined step shaft via a coupling. We found this setup to cause extreme vibrations and our small couplings would often come loose.

I believed that these vibrations (which I thought had to do with the lack of concentricity with our setup) also caused y-variability with our shooter so on our practice robot we are trying to run the 8" pneumatic wheels directly off of the 3:1 VersaPlanetary with an RS-550 on each. Looking at the motor curves, I figured that we could get close to the ~4500 r/min that we had with the CIM with this setup. Perhaps I am wrong.

When we tried powering the VersaPlanetary (with the Pneumatic wheel attached via 1/2" shaft and 1/8" keyway) using an FRC battery, the wheel would quickly get up to speed however after about 10 seconds a burning smell developed and we could see smoke coming out of the gearbox, not the motor.

We applied white-lithium grease moderately and did our best to follow the instructions for assembling the gearbox and motor.

From those more experienced than I, should I even be trying to direct drive a pneumatic wheel with the VersaPlanetary at 3:1 with the 550? Do you even think I could get the wheel up to 5000 r/min?

On to the smoke problem- should I try spacing out the motor mounting plate? It is not too hard to spin the output shaft by hand however it is pretty jerky. We inspected the gearbox afterwards and it appeared fine. Should we just try reassembling the motor onto the gearbox?

Also, it heated up quickly when powered on.

Hopefully Paul Copioli will see this and offer some advice.

Thanks!

Re: Prototype Small Wheeled Shooter
 

Andrew,

Don't be so sure that the smoke isn't coming from the motor. The VP is designed to have vents to the motor form the motor mounting plate. Smoke form the motor could definitely look like it is coming from the VP.

With that said, my team is running 2 VPs on our shooter with 8" pneumatic tires and have seen no such smoke. We are using RS775 motors with 5:1 and 3:1 There really isn't anything inside the VP that would smoke very long before seizing.

I suggest you look at the current the motor is drawing while just attached to the VP. Some people have reported problems getting the RS550 motor lined up properly while installing into the gearbox. That could be causing excessive loading on the motor causing it to overheat.

Paul

Re: Prototype Small Wheeled Shooter
 

When we were first running our shooter with 3:1 Versaplanetaries with BAG motors, the gearboxes would get very hot, while the motor (and the wires to the motor) were cool. We tweaked the spacing of the sun gear on the output shaft just a little, and that solved the problem.