ARchangel

[PVC Arsenal 17]

Electro Pneumatic Revolver (EPR) proof of concept.

More pics and vids tomorrow... I'm exhausted.



-Mark

[Gaderelguitarist]

Whoa.

[mark.f]

Aww come on man. Seriously? A 320x240 picture and no explanation?

Why do you do this?

EDIT: I even tried opening your Photobucket account... private.

[PVC Arsenal 17]

Aww come on man. Seriously? a 320x240 picture and no explanation.

Why do you do this?

I was merely attempting to hide the fact that the gauge was installed upside-down... this forum is full of critics.

Basically it's a 15-shot pneumatic revolver that uses a microcontroller to handle the firing and indexing sequence. CO2 powered, removable rotary clips, full&semi-auto capable... etc.

[mark.f]

Nah, I was just remarking towards the fact you post a very mean looking cannon, but leave me tossing and turning in my sleep as I wait for the write-up tomorrow.

(From what I can see) it looks great. Can't wait for the write-up.

[PVC Arsenal 17]

This'll do some explaining while I finish stuffing the electronics in the foregrip: http://s237.photobucket.com/albums/ff15 ... irtest.mp4

[POLAND_SPUD]

what does it use to drive the step motor? l293d?

the fact you post a very mean looking cannon, but leave me tossing and turning in my sleep as I wait for the write-up tomorrow.

I don't know if you have noticed but he does this all the time

[django]

wow!, looks fantastic!!! we eagerly await more info on this DAMN YOU

[PVC Arsenal 17]

what does it use to drive the step motor? l293d?

the fact you post a very mean looking cannon, but leave me tossing and turning in my sleep as I wait for the write-up tomorrow.

I don't know if you have noticed but he does this all the time

No step motor actually, I decided against them due to their high power consumption. Inside the main pipe is a 6V electric screwdriver. It provides high torque for turning the barrels and offers a convenient hex socket for easy intallation/removal of the barrels. Indexing is performed by a limit switch. Each barrel hits one as it passes over the switch and the appropriate action is taken in the Arduino sketch (I.E. stop turning and fire).

The motor and solenoid are fired using two basic N-channel logic level MOSFET circuits from a separate battery. The motor was pulling about 3 amps and it was too much for the normal motor driver IC.

And sorry, I like being a pain in the ass...

Had it not decided to snow again, I would have the free time to take this thing outside for some shooting. Next weekend perhaps

[POLAND_SPUD]

I decided against them due to their high power consumption

The motor was pulling about 3 amps and it was too much for the normal motor driver IC

hmm that's surprising... it's a geared motor, right?

Couldn't you use a small step motor? that would make more sense IMO

[PVC Arsenal 17]

It's geared, yes. This approach was much simpler. I don't think a stepper would even have the torque to turn the assembly.

Full-auto uncapped dryfire: http://s237.photobucket.com/albums/ff15 ... nt=fau.mp4

[jrrdw]

When is the live fire coming? ROF? Did I miss that or your not sure??? Nice work!

Edit: Live fire next weekend maybe...

[irisher]

Am I missing something or are your barrel(s) only a few inches long?

[PVC Arsenal 17]

The barrels are four inches long, enough to fire Nerf darts. I'll be able to demonstrate that next time I come home from school, maybe this coming weekend.

[PVC Arsenal 17]

EDIT: better video: http://s237.photobucket.com/albums/ff15 ... IM0976.mp4

Here are some videos, excuse the crappy quality:

http://s237.photobucket.com/albums/ff15 ... nt=fa1.mp4

http://s237.photobucket.com/albums/ff15 ... 012021.mp4

As you can see there was not one misfire in either mode. The indexing is dead-on accurate. However, if the barrel assembly is put back on out of line with the air outlet, there is a "synchronizing period" of a couple shots before it gets back in tune. Once it is, though, it's consistent. I'm still working on ways to eliminate that problem but overall I can't complain about how well the whole system is working.


And of course a size comparison to my other toys:



Note the electronic guts sticking out... there is much refining left.