pic: 1251 Prototype v 1.2

[sanddrag]

What kind of accuracy can you get over that range? Can you make 10 in a row into the goal?

[Jon K.]

My guess would be around 1800 but its hard to tell becuase of the sprocket sizes, my guess would be the big one is around 40-50 teeth probably maybe even 60 and the small one around 10-20ish maybe....

[Wetzel]

1750ish...

Wetzel

[David Guzman]

Originally Posted by sanddrag

What kind of accuracy can you get over that range? Can you make 10 in a row into the goal?

We made about 5 or 6 shots and they all hit the ground in about the same spot.

In my opinion it is very accurate.

[Kyle Love]

Nice shirt kid in the background

[Eric Scheuing]

Very nice idea. I think it might be a winner.

About 1775 rpm?

[b-rant]

I have to say this seems to be the best way to shoot because the 4 wheels help guide the ball to the needed derection and the constant motion allows balls to pass though as fast as need. seems to be going 4m/s? maybe.... so i don't know any calculations for that but......2,329rpms?

[natis]

really nice guys !! working pretty hard huh...

[tkwetzel]

Well...I finally made it back to Chief Delphi after being away for so long.

The sprocket size should not matter at all to answer their question. They asked how fast the wheels were spinning, not the motors. With an angle and distance you need the size of the wheels and possibly height of the arc of travel to find the rpm of the wheels to launch one of the foam balls that far.

Without calculations I will guess that the wheels are spinning at 1,900 rpm.

[Andrew Blair]

The size of the wheel has nothing to do with the RPM of them (Unless you say that their mass slows down the system). If we know the output speed of the Kit gearbox, and we know the ratio to the the wheels, we can, with some error, find the RPM of the wheels. Now, if we were looking for the linear speed from a reference point on the wheel, then wheel size would matter.

[Tom Bottiglieri]

Originally Posted by Andrew Blair

The size of the wheel has nothing to do with the RPM of them (Unless you say that their mass slows down the system). If we know the output speed of the Kit gearbox, and we know the ratio to the the wheels, we can, with some error, find the RPM of the wheels. Now, if we were looking for the linear speed from a reference point on the wheel, then wheel size would matter.

Who says the trannies are running at full power?

[Andrew Blair]

Originally Posted by Tom Bottiglieri

Who says the trannies are running at full power?

Thats one of the easiest assumptions. They're running the motors straight off of the battery, so the speed of the output is defined only by the battery voltage. Its rather easy to say that they were running a fairly charged battery; most people don't run a battery to nothing and then use it to power a launcher. An easier assumption than the estimation of the size of those two sprockets.

[i_am_Doug]

EDIT: im now guessing your team number ;p 1251.

[cire]

Looks like 1269 RPM to me

gear ratio * free speed of kit transmisson
3:1 * 423 rpm = 1269 rpm

edit - I estimated that the larger sprocket was 36T and the smaller one was 12T by looking at the picture.

[Rick TYler]

I know I'm coming late to the party, but 1,250 rpm, plus or minus two weeks.

(Bonus if you recognized the obscure movie reference.)