3 Balls in a second and a half

[Ether]

Originally Posted by ratdude747

they look custom, probably lathed.

Ya think? I wonder what they cost.

[Manoel]

Originally Posted by Ether

Ya think? I wonder what they cost.

One mighty flywheel! Under some assumptions¹, I would say the largest roller takes about 6 seconds to spin up to full speed! Am I correct in my assumptions?


¹ - Dual RS775-18 motors directly coupled to the solid aluminum roller, approximately 100 mm wide and 100 mm in diameter with an 85 mm radius, giving a moment of inertia around its rotation axis of ~1067746.85 g-mm². Negligible frictional losses.

[jason701802]

How much do each of the rollers weigh by themselves?

[Pun-isher]

Looks fairly heavy considering how high it will be mounted, but very solid shooter.

The speed may be slightly overkill, maybe 2 seconds for all three balls but that's just me.

[nikeairmancurry]

Originally Posted by LedLover96

Is your shooter wheel direct driven by two BB RS775s? I didn't see any gearing in the video.

It is direct driven. The reason we went with this was because we had success with a similar design in 2006.

Originally Posted by Manoel

One mighty flywheel! Under some assumptions¹, I would say the largest roller takes about 6 seconds to spin up to full speed! Am I correct in my assumptions?

¹ - Dual RS775-18 motors directly coupled to the solid aluminum roller, approximately 100 mm wide and 100 mm in diameter with an 85 mm radius, giving a moment of inertia around its rotation axis of ~1067746.85 g-mm². Negligible frictional losses.

Very close, around 7 seconds was where we thought, but while its ramping up, we have plans to occupy the time.

Originally Posted by Pun-isher

Looks fairly heavy considering how high it will be mounted, but very solid shooter.

The speed may be slightly overkill, maybe 2 seconds for all three balls but that's just me.

Slow motion video had it 1.5 secs, but its a rough estimate. Again its not a final interval we want, it was just something that happened during testing.

For those asking about the rollers, they are custom made on a lathe.

[372 lives on]

so shiny i am jealous...

[Basel A]

Epic! Reminds me a bit of the best dumpers of '09. I definitely like the aluminium rollers; you're not losing much speed as the balls come out. As for the spacing, it certainly makes sense to slow it down when you're in the key, but if you're in some other area of the field playing against defence, make sure you have the spewing ability! Unless you're a key-shooter, that is.

[RedLeader342]

this is awesome sauce..

[JamesCH95]

Originally Posted by nikeairmancurry

After cutting out some weight its about 15 lbs... Yes heavy, but very effective so far...

Yikes, that is heavy. Is the robot unstable to drive or balance on the bridge?

[nikeairmancurry]

Originally Posted by JamesCH95

Yikes, that is heavy. Is the robot unstable to drive or balance on the bridge?

Nope, its reinforced very nicely...

[JamesCH95]

Originally Posted by nikeairmancurry

Nope, its reinforced very nicely...

Not structurally unstable, but dynamically unstable. 15lbs is a lot of mass to have so far off the ground.

What speed(s) are you geared for in the drive train?