Re: pic: Team Fusion's T-Shirt Shooting Robot
 

errr not really. The electricity will flow to a ground but it must be of suitable mass. A bar probably would not be enough. Actually you know if you want it might be easy to use an anti static guard and ground to a person. Uhh I never support or recomend hitting anything with a metal bar. :rolleyes:

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

Jeez, how do you guys keeps the newbies in line?(J/K!) :D

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

I scare them by getting them to touch both ends of the battery (also good at getting them to be comfortable around it). Seriously i don't know why you would need to use insulation. Static shock that you feel have high voltage but almost no ampage. However if your already connected to it when you use it you won't even git that shock.

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

We just finished our air cannon, and it works relatively well! Heres some video of it after some short time tuning it.

CRT T-shirt Cannon

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

Very well done!
We have been using ours at home games and let me say, it has really caught the attention of our school, sponsors and community. Suddenly people are aware of the Robotics team that never really knew anything about us. We are receiving requests to launch a several different team events in the coming months. We had a request from a local dance studio to launch during a performance of "The Nut Cracker" (Long story for another time). The local News Paper is going to be interviewing us for an article. A new sponsor (Schwann Food's) wants us to launch their shirts wrapped around gift certificates at the next two games. All I can say is, we never thought so much attention would come from something so fun!!!!

By the way, I noticed this on your video too, doesn't it make a really cool sound when it fires, a real head turner! You can hear that sound from 80 yards away over the din of the crowd at a fully packed football game!!!

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

It really does turn some heads! It really is a loud kind of pow!, and the thing even recoils a bit. Right now we're working on fixing the arm so that it can aim, because being so old, the gearbox has kind of fallen aprt and needs an overhaul. I would also like to add another compressor to it so it'll charge more easily. It's been so long in the making. We threw together the tank and barrel in about four days, then sat for three weeks waiting for the Lowes valve! Our store recently discontinued their stock, and the main distributor was out of stock oddly. Anyways, we're fine tuning the range now, and we can currently get like 40-50 yards. The t-shirt projectile itself is the object of attention right now.

Something else I though was really cool that I'm sure your's does too: when you fire that sucker, water condensation wisps out of the barrel like gunsmoke. Pretty flippin awesome!

P.S.- I'm the idiot on the hill! :D

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

If I didn't know better, I would say you were talking about our canon, err, ahhh, excuse me, T-Shirt launcher.
We really haven't seen a need for a second compressor, by the time we get it re-loaded, the chamber is up to pressure. As for the POW!!, I always thought it sounded more like someone getting punched right in the diaphragm. The sound of air rapidly escaping the lungs is fairly close to what you are hearing.
We definitely see the condensing air at the end of the barrel as well, it's really cool!

Do your selves a favor and chart your distances based on elevation and pressure. My guess is you will find out that it is surprisingly consistent. At 60psi, you should get a maximum distance on a rolled, rubber banded t-shirt, launched at 45 deg. elevation of................175 ft.

BTW, I just ordered a pressure regulator that will allow us to regulate up to 100psi. (I see 230 ft. + coming :D )

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

Haha, it must be something with mentors, ours is having more fun than we are I think! We send the shirts at about 80- 100 psi, no regulator. We're just watching the gauge right now, but intend to use a pressure sensor in a bit.
What we've found, although it's still in it's infant stages, is that you begin to drop off with distance increasing after about 80 psi. You get about 3-5 yards further with that extra 20 psi, but thats it. Might be the weight of the shirt. But boy is it accurate. We can consistently put it into about a 3 yard circle at 30 yards. Its pretty fun to see is load the thing though: we use a shovel handle and ram the thing down in for a nice tight seal. It looks like you're seriously loading a cannon. The place where we fire it is on an access road behind our school that gets quite a bit of traffic, teacher and otherwise. We get some awful strange looks in the morning! I am considering the ballistics table once we get the thing consistent.

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

The Chinese have already thought of this.

Repeating Crossbows

All that really needs to be done is modify the crossbow/launcher thing so that the lever is prolly pneumatically operated.

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

wow, I've never seen that before. Pretty impressive(reminds me of Perfect Dark :D ) Unfortunately, we're dealing with pressure, so we've got to have the seal. Perhaps if you took mechanicalbrain's bolt idea, and simply used a spring magazine, you'd be able to pull something similar off. :)

Edit------------------
If you meant using the actual crossbow to launch the t-shirt, that would definitely work. Seems like an indirect way to throw em though. ( pressurize the same volume of air to compress the bow, instead of just using that air to throw it. Besides, it makes a loud boom! :D

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

That's correct. The pneumatic piston is connected to the lever instead of it being hand-operated.

Here's a reasonably detailed explanation of how this works.

There is only one real problem with this repeating crossbow, the drawstring wears faster because of the effort of being pushed up and down. One possible solution to this is if there is some sort of replaceable protection for the drawstring (duct tape, plastic, alum foil, etc.)

And, I'm not sure of you've ever heard one of these in action but if you purposely set the slot on the side of the mazagine so the string always hits the stop. It should make a sufficient enough sound, though I'll admit we all know how cool the "thump" of a pneumatic cannon can be. :p

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

As some may have seen in another thread... We are redesigning our T-Shirt Shooting Robot. We should be finished soon and we'll have pictures and video of it later.

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

Could you possibly post your design for the t-shirt shooter as well? It would be helpful for some of the teams that have interest but don't how to attack this machine.

Thanks,
Pavan.

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

I will certainly try... I just got SolidWorks, and this will be my first time using it, but I will try to draw it up on there.

Re: pic: Team Fusion's T-Shirt Shooting Robot
 

Thanks man, and take MILLIONS of pictures :D!