Shooter wheel covering

my opinion: I would be more concerned with tread pulling from rivets or anything else that’s “stuck” onto a wheel pulling apart then the pneumatic tire material breaking.
My (limited) evidence: I still get pretty nervous when seeing the tire “pancake” a bit at higher rpm when it is filled to “a little bit more than flat”, but our 5+ year old tire has never failed. I HAVE experienced andymark tread coming out of rivets twice in 2009 when we were spinning a traction wheel at ~4000 rpm. Also this

Pneumatic tires are designed to spin fast (e.g. on automobiles), while robot wheels are not. They have cords under the tread to hold them together. I’d feel much safer being near a robot with a (properly balanced) pneumatic tire spinning at 6000 RPM than a robot wheel with stuff stuck to it spinning that fast.

Cars have steel belts in the tires. Small tires like wheelbarrow tires do not. Also, car tires don’t spin at 6000 rpm. A typical 15" tire is 25" diameter - giving around 812 r/mile, which is 812 RPM for 60 mph.

Here’s what we bought at Home Depot:

We aren’t the most scientific when it comes to how much compression? It was trial and error. We’ve made our shooter adjustable at the side wheel and at our top driver motor wheel and did everything by touch, feel and sight. Our Mark II eyeballs did the trick. We used a piece of rubber weatherstripping (after trying several thicknesses) on the wall. We’ve put 2" teflon tape from McMaster-Carr on the shooter “rails”. Compression? Don’t have any. We use an Andymark 6" wheel from 2011 KoP. We’ve constructed several wheel replacements for the tournament. Again, we attached this material to the wheel, custom cut it, and glued it down with gap filling CA.

I spent some bucks on pneumatic wheels but the performance was not optimal. We’re shooting 90-99% at 30’, 80-90% at 40’. We’re using one (1) CIM directly attached to the wheel with an 8mm hub . We’ve got another drive on the top of our shooting mechanism so we get spin from the side and push from the top. It works, is robust and is simple. For our team, simple is good. Not many of my students know how to turn screws but we’re learning every year. We’ve got an acrylic cover over the side wheel for safety’s sake. We’re not fancy, nor do we have a huge bankroll. We try to use KISS principles and keep the costs to a minimum.

Our shooter runs with 1" of disc compression with the pneumatic wheels. Result.

Compression on the wall of the shooter, though, instead of the wheels may be totally different. The compression of the pneumatic wheels help grip the frisbee and throw it better.

Either way, try adding more compression with both a solid material and something compressible on the wall and see what happens.

It is. they are definitely 2 different variables with different effects. Unfortunately, I think a lot of teams are not fully testing the 2 and missing out on some performance choices they could have if they understand the difference.

Nice bot in the video btw!

When you say 1in of compression what do you meen by this. When i think of compression i think about if the gap between the edge of the wheels to the wall is the diameter of the disk(what 11in is that), whatever amount you remove from that is the amount of compression. So compression of .25in on an 11in disk the space measured would be 10.75in. The reason i ask is because the 1in you mension seems an awful lot that the way i consider it.

It’s entirely possible that the space between the wheel and wall is 10". I wouldn’t expect the frisbee to be compressed 1" if this was the case, rather the pneumatic tire deforming a portion of that.

it is 10" from wall to wheel. The pneumatic wheel does compress a bit but we run 20psi in them, its mostly seen in the frisbee (it deforms quite a bit if you push it through slowly)

With our pneumatic wheel set up, we are actually bearing more on the side of the tire. The tire helps to keep the Frisbee down on the platter. The tire height is optimized for the wheel speed. It has been consistent and we are not seeing a lot of wear on the tire…

I was at the gtr east today and noticed several teams using an adhesive rubber that was fairly hard but still compressibly with a slippery surface. Does anyone know where i might find something like this. Me and some of my team mates were talking today and think it would be a good siding for our adjustable wall. It should allow for some compression but low friction for the frisbe to slide along while being spun and accelerates by the wheels.