5010 T-Shirt Launcher Prototype

[waffle_dynasty]

Team 5010 is working hard on building a t-shirt launching robot this off-season!
We've built a prototype bot out of wood already, and hope to have a cool finished robot by the start of basketball season.

Here's some information about our t-shirt bot:
-8" pneumatic wheel drivetrain
-SCUBA tank and secondary "per-launch" air chamber
-Shots at 80-100psi
-6 barrel revolver
-All-thread angle adjuster
-Nearly autonomous operation

Here's a link to a video of one of our test shots at 100psi:
www.youtube.com/watch?v=UkJm71YgmSk

We look forward to sharing our finished product with Chief Delphi soon!

[nuclearnerd]

Looks great!

Celt-X built a wheeled and a pneumatic t-shirt shooter this summer (https://twitter.com/celtxrobotics/st...24864/photo/1). pneumatic shooter has a range about the same as yours at 100 psi, and the wheeled one shoots about half as far.

*but*

the pneumatic cannon only use a 5 gallon, 100psi air tank, so we have to turn it down to less than 50 psi to keep enough pressure to shoot all four barrels, which reduces the range considerably (https://twitter.com/celtxrobotics/st...38240/video/1). A scuba tank or carbon dioxide cylinder would work better of course. Where do you go to refill yours? How much does it cost? How many shots do you get from a full tank?

[waffle_dynasty]

Where do you go to refill yours? How much does it cost? How many shots do you get from a full tank?

We refill our tank at a local oxygen supply store for $5.
We've gotten well over 50 shots off with our tank so far. Given that it's only been filled once and we still have air left, we expect about 80 shots per tank.

[MeGuttieri]

Nice! Good luck to you guys.

[GeeTwo]

Originally Posted by waffle_dynasty

Team 5010 is working hard on building a t-shirt launching robot this off-season!
We've built a prototype bot out of wood already, and hope to have a cool finished robot by the start of basketball season.

Here's some information about our t-shirt bot:
-8" pneumatic wheel drivetrain
-SCUBA tank and secondary "per-launch" air chamber
-Shots at 80-100psi
-6 barrel revolver
-All-thread angle adjuster
-Nearly autonomous operation

...

If you're planning to use it during basketball season, either you're using too small of a solenoid valve or you're going to have shirts hitting the roof of any normal-sized gym. We launched a t-shirt over the top of our football stadium last night with less than 60psi in the secondary tank, using a 3/4" diameter solenoid valve.

Originally Posted by nuclearnerd

A scuba tank or carbon dioxide cylinder would work better of course. Where do you go to refill yours? How much does it cost? How many shots do you get from a full tank?

We got our scuba tank at a local dive shop and get it refilled there, as well. The stock scuba regulator cuts the pressure down to where an FRC-standard regulator can take it to our working pressure. I understand that firehouses also typically have scuba-charging facilities; for a time we could get our tank filled for free, though it was possibly because our first head coach's brother-in-law is a fireman.
How much you get depends largely on how well you ration the air. With our arduino code, which measures the solenoid open time (40-50ms IIRC), we can do several hundred launches. We lost an xBee recently, so we cannot use that code. With our current hack set up,* the time is based on how long the driver holds the button down, we managed to get through the homecoming pep rally and most of the game (at least 100, probably about 150 shots).

* The hack set up uses a roboRIO loaded with our unmodified 2016 competition code. The intake/low goal roller controller drives the two solenoid valves. That one is forward and the other reverse is effected by diodes soldered into the wiring harness.

[carpedav000]

Originally Posted by GeeTwo

If you're planning to use it during basketball season, either you're using too small of a solenoid valve or you're going to have shirts hitting the roof of any normal-sized gym. We launched a t-shirt over the top of our football stadium last night with less than 60psi in the secondary tank, using a 3/4" diameter solenoid valve.

Barrel length and cylinder seal could also be effecting their ranges. If the solenoid is the issue, though, longer barrels should do the trick

[waffle_dynasty]

Originally Posted by GeeTwo

If you're planning to use it during basketball season, either you're using too small of a solenoid valve or you're going to have shirts hitting the roof of any normal-sized gym. We launched a t-shirt over the top of our football stadium last night with less than 60psi in the secondary tank, using a 3/4" diameter solenoid valve.

Originally Posted by carpedav000

If the solenoid is the issue, though, longer barrels should do the trick

Thanks for the input guys! We'll do some more testing to see how lowering the air pressure and increasing barrel length affects our shots.

[alexchrisman]

Love the looks of it! Hope to see it in action soon!