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Posted: Sat Oct 06, 2007 5:41 pm
by HaiThar
So how should the setup be?

Posted: Sat Oct 06, 2007 10:06 pm
by HaiThar
Gepard wrote:You won't have much control though - DC motors are the best way IMO......
I'm really stuck on this pneumatic cylinders idea!

look at MCMaster part number 6498K159. I can use two of these, connected up to like a compressed air source. Come to think of it, hell, I could use the same air source for my cannon as the pneumatic piston. I throw a regulator on there, and a solenoid valve, and voila! a pneumatic powered piston. The only thing you have to do now, is figure out a way to do the vertical axis...I COULD do a pneumatic slide but those are PAINFULLY expensive.

Do you have any ideas on how it would be possible to connect an air pressure reader up to a microcontroller input? :\. I am stuck on this.

Posted: Sat Oct 06, 2007 11:10 pm
by miskaman
Holy crap, that would be almost going overboard. Servo motors and wind readings. My gosh.

But I don't know if CD drive motors would be powerful enough. It depends what the frame is made of I guess. Steel would be the strongest and easiest to work with if you have a welder and know how to weld.

Maybe you should use the motors from a car that roll up the windows? I think you can get them preety cheap from a repair shop or a salvage yard.

Posted: Sat Oct 06, 2007 11:18 pm
by HaiThar
miskaman wrote:Holy crap, that would be almost going overboard. Servo motors and wind readings. My gosh.

But I don't know if CD drive motors would be powerful enough. It depends what the frame is made of I guess. Steel would be the strongest and easiest to work with if you have a welder and know how to weld.

Maybe you should use the motors from a car that roll up the windows? I think you can get them preety cheap from a repair shop or a salvage yard.
That's going to be the effect/theme I'm going for. I'm going to have lots of "hardware" looking stuff(I.E. modem boards, old memory chips, ect.) encased in plexiglass to give it that futuristic look.

Posted: Sun Oct 07, 2007 8:46 am
by mark.f
That cylinder is almost the same thing we were going to use on our vertical axis control. You just need a 4-way, 3-position "closed center" valve to control each cylinder accurately. A flow regulator before the piston wouldn't be a bad idea either, just in case you get a tubing that allows too much flow to control the piston accurately.

Posted: Sun Oct 07, 2007 9:11 am
by HaiThar
markfh11q wrote:That cylinder is almost the same thing we were going to use on our vertical axis control. You just need a 4-way, 3-position "closed center" valve to control each cylinder accurately. A flow regulator before the piston wouldn't be a bad idea either, just in case you get a tubing that allows too much flow to control the piston accurately.
Yes I know, the only problem with that is it only allows the Horizontal axis to move one way.

Posted: Sun Oct 07, 2007 10:56 am
by Gepard
HaiThar wrote:Do you have any ideas on how it would be possible to connect an air pressure reader up to a microcontroller input? :\. I am stuck on this.
Gepard wrote: Pressure can be done with a pressure transducer though most need to be fed through some form of unity gain buffer for stability and then a diff amp at the end with a gain of 10 otherwise you'll get allsorts of readings. It's not just a case of hooking them up to an ADC pin and yanking a reading.

Posted: Sun Oct 07, 2007 3:56 pm
by mark.f
Yes I know, the only problem with that is it only allows the Horizontal axis to move one way.
Eh? Are we talking about the same cylinder? A double-acting cylinder with a 4-way control valve with closed center will allow you to control the horizontal axis both ways.

Posted: Sun Oct 07, 2007 4:08 pm
by VH_man
lol. i like this. Mabey i could make a cannon with accurate enough ammo so that i could type in GPS coordinates, and BAM those coordiantes are toast. hehe.

anyway, this is pretty cool. someoene should make one of these for a hybrid, everything all in a project box....

"Propane Armed?, Check, Meter Ready?, Check, Applying Propane Pusle! (fshht) (buzzer turns on), Meter Disarmed? Check. Applying Proper air pressure for measured concentration of propane.........

BOOOMM!!!!

lol. this could actually be great for hybrids. type in 5X mix and the computer does it perfectly every time..........

Posted: Sun Oct 07, 2007 4:35 pm
by HaiThar
markfh11q wrote:
Yes I know, the only problem with that is it only allows the Horizontal axis to move one way.
Eh? Are we talking about the same cylinder? A double-acting cylinder with a 4-way control valve with closed center will allow you to control the horizontal axis both ways.
Wait, are you sure it extends both ways? I thought it only went one way. By double acting, I think it means it has two places for air to go in.

Posted: Sun Oct 07, 2007 4:40 pm
by Gepard
Yeah if the switch has three postions you have up/off(stop)/down.

Posted: Sun Oct 07, 2007 4:57 pm
by HaiThar
No I'm talking about the piston. It only extends one way. So for the horizontal axis, I need a slide, not a piston. I'm thinking of using 6723K11, powered by a 9v motor... Thoughts?

Posted: Sun Oct 07, 2007 5:18 pm
by Gepard
No, lets say you have a pneumatic cylinder thats vertical. The switch will pump air into the bottom pushing the piston up. Then you say off and it stops. Then you say down and it pumps air into the top pushing the piston down....Make sense?

Posted: Sun Oct 07, 2007 5:30 pm
by HaiThar
I was just going to release the air through an actuated valve, and let gravity bring it down.

Posted: Sun Oct 07, 2007 6:17 pm
by mark.f
A double-acting cylinder works both ways. Air ports on either side of the bore feeds air into the cylinder on either side of the piston. The four-way valve allows you control this sensitive system fairly well.