Blank Firing Pistol

[cedd]

Those are the fellas yep! I'm using a Bogeyboard for the transmitter and the RDF1 for the receiver. The only slight down-side is that the receiver is active high outputs, whereas the mp3 player boards are active low inputs. The midi side is handled by a teensy so that can be whatever I want it to be. Opto isolators are probably going to be the best way forward, unless I use the teensy as a kind of buffer - when an input goes high I pull down an output.

 

Yes it has occurred to me that car remotes could interfere, but these modules use their own pairing protocol and are pretty resilient. I guess if you left the faders up on the desk all the way through the show then maybe there's a chance of a false trigger if one of the audience is fiddling in their pocket, but the chances are tiny, and if you run with the faders up all the way through then you're maybe asking for trouble anyway. Put them up for the scene and then let the gun handle the precise timing would be my advice.

[alistermorton]

Presumably these units are simple to pair and reasonably resilient. Can you pair multiple transmitters to a single receiver easily, or do you need one receiver per transmitter?

 

I may have to look into this sort of thing for future use.Thanks.

[sleah]

Yes it has occurred to me that car remotes could interfere,

Opportunity for shenanigans :D

 

Outside of the scene have it trigger a 'beep-beep' sound and have a couple of orange pin spots flash..... ;)

[dbuckley]

The units I use aren't as cute as those units, they are remote garage door openers from Ali. The receivers are "nicer" in that they are a ready to go thing in a box just needing 12V and they have relay contacts, but the transmitters are a tad bigger. Available with 1-4 buttons and relays. However, because there is full software support around the RF elements, one can select one of several dozen "channels" to transmit on, they aren't channels, they are encodings, and the receiver can be paired with a tx by pressing a button on the receiver to put it into learn mode, and then transmit and the LED flashes and they are mates.

 

If size isn't an issue these units are just great.

 

http://davidbuckley.name/pix/tx_in_gun_stock.jpg

 

Yeah, awful picture, I know. The wires just go across the contacts for one of the buttons.

[cedd]

My crossbow used one of those modules in its' first iteration. It worked really nicely. My hope this time around is to remove relays from the signal path if I can (I'll still be driving a relay output that'll be available for pyro, solenoids etc. but it won't be in the triggering path, it'll be an output of the Tensy) just to make sure the thing is super quick at triggering.

 

The 3d print is finished and looking pretty nice. I've even managed to model the tips of bullets in the cylinder. It needs some tidying up before it'll all fit together but it's getting there.

Now to build the enclosure for the receiver. Just weighing up how close I dare put the Teensy to the receiver before it has an adverse effect with spurious emissions. That'll be an experimentation job I think. Ideally they'd be stacked on top of each other but I think that's maybe asking for trouble a bit.