How to send notifications?

I'm trying to form ideas on a project for a class I'm taking this summer. It has to be interactive and involve Arduino. I thought about creating a shooting gallery. My intent would be to create a gun that emits IR and have each of the targets use an IR receiver. Once the IR receiver receives a signal, it will trigger an action and the target will move. The intent will also be a display with maybe a timer and also records the number of hits.

I'd like to prevent having to run wires everywhere and I would like to have the targets communicate with the "home" to record the hit.

1.) Will I need an Arduino board for each target or is there a way to trigger the targets using only 1 board? I currently have 1 Uno.

2.) Is IR the best idea for triggering the boards? I don't really think I need Xbee, but I'm not well versed in that either. My idea was to have the gun send the IR to the IR receiver at the target. The target receives the signal, triggers the motor or actuator at the target and also sends an IR signal back "home" to trigger the hit.

Will my ideas work or do I need to look into other things?

My concern would be the IR spreading out too much, but you might be able to constrain it in the gun barrel.

As for the Arduinos, receiving IR (like remote controls) is pretty timing dependent, although a simple "on" or "off" might be much easier to achieve.

I haven't tried this, but I think this would be a case where you would need to experiment.

If you can stop people staring down the barrel, a laser light might be more precise.

That is a good idea. What would I use to receive the laser signal? Do you think I can build the gun so that it only fires a brief shot and the person isn't able to just hold the trigger down and hit the target?

Our goal is to build everything out of used electronics. We've been tearing stuff apart for components and I tore apart a portable CD player today. Would I be able to integrate that laser into the gun to use for the project?

Thanks so much for the idea.


Nick's right, a main question is how big a "spot" do you want the gun to project at the target distance. What's the probable distance? You can easily control the length of time a "shot" is active.

IR will spread out, but you can focus and contain it.

Laser would be good, but very small. The sensor would be also small, so the accuracy needed would be equivalent to hitting that .22 inch bullseye with a .22 bullet. I used to be able to do that about 4 out of 10 times, standing, but that was 50 years ago... Maybe a larger simple lens would make the target area bigger..

IR receivers are low-cost and good at ignoring room light: IR How-To Here:

Let us know what you end up doing...

If you are looking to avoid wires and send the results to the arduino you can look at xbee though that will increase the cost of the project. On the note of using lazer vs ir I think it is a good one. On ebay you can pick up a 3v or a 5v lazer pointer with a positive and negative lead that would fit perfect on a toy gun, price is less then 10.00 for a few of them. On the target you can use a light sensor, this will take some calibration but you can say if if light is greater then x then do score.

Do you know if anyone has had any luck salvaging a laser out of a CD or DVD player and using it for something like this? I have access to some old ones and wouldn’t mind doing something like that for no other reason than to say I did it.

There is a project i saw on you tube where they use a dvd player laser and board to do a laser light show. Not sure how to get it out. Check dealextreme they have a few for less then 6.00 might be easier.

So something like this:

Looks like it would be VERY manageable!

Could I use this to detect the laser at the target?

I just want to be sure by looking at the specs that the phototransistor will detect the laser.

not sure how much this adds to the conversation, but about 10-15 years ago when I was at Cedar Point in Ohio, they had about 2 or 3 shooting galleries. The guns looked like rifles and were tethered to the bar area where the players stood and there were maybe 8-10 guns available for use. Actually, the shooting galleries have been there for the past 25+ years unchanged as far as I can remember.

Here is a video of the gallery:

The targets appear to be nothing more than a red plastic circle with some sort of LED or other light behind them. I am unsure how they (target and gun) communicated with each other, but I do remember that the guns made an audible "psssss" sound, almost like they were connected to some sort of compressed air tank to produce a firing sound. The gallery itself was shrouded from the sun, so it could have been a simple light emitter, though I am thinking it was IR based since there still needed to be light inside the gallery so you could see what was going on.

UPDATE: Did some searching and found a PDF manual for an IR shooting gallery toy that has an IR blaster gun and 3 target pods. The diagram of the toy also points out where the IR receivers are located, as the targets themselves are nothing more than card board sitting on top of the pod unit.

And while using a laser may sound like the simplest idea, a laser is also quite dangerous if the wrong person is wielding the gun. What you may want to do is use a lens to help focus the IR beam so it doesn't spread out everywhere, even if you have the IR LED deep within a toy gun barrel. With the proper equipment, most of which is mentioned in this forum post you should be able to get a "sweet spot" of sorts, or a "sweet range", where the focused IR beam's spread is just about right, and then you can arrange targets accordingly. Too far back, and the beam will be too large and possibly engulf more targets than you intend; too close and the beam may not be large enough that it would require a real sharp-shooter to hit the target.

if i were building a shooting gallery, which actually sounds kind of fun, i would set up the targets in groups, each group connected to a microcontroller. I haven’t run into any projects yet where I have had to do this, but I assume I could get an IR receiver to send out a simple HIGH or LOW logic signal depending on if it picks up an IR signal or not, rather than something like a photosensor that can return a large range of values depending on the amount of light hitting it. If this is possible, a simple Arduino UNO could have as many targets as digital inputs (although you wouldn’t want to do that, as you still need pins to handle any target animations and such, like is shown in the video i posted above). Also, target-to-base communication could be a simple 1-way communication. The targets don’t really care about the shooters score, but only if they have been successfully shot at or not, so the base doesn’t need to communicate with them at all. However, if you wanted the base unit to be able to tell the target pods/groups to do some sort of diagnostics, that is when 2-way communication would be needed.

hope the project turns out good. please post pictures and video of your project, either during development or when it is finished. It sounds like tons of fun

macharborguy: if i were building a shooting gallery, which actually sounds kind of fun, i would set up the targets in groups, each group connected to a microcontroller. ...Also, target-to-base communication could be a simple 1-way communication. The targets don't really care about the shooters score, but only if they have been successfully shot at or not, so the base doesn't need to communicate with them at all.

All I have to say, macharborguy, is that you are an effing genius! For nothing more than the simple fact of that is EXACTLY what I was thinking.

I'd like to have more than 2 or 3 targets and I don't want to buy 10 Arduino boards so I thought about having maybe 2 or 3 targets connected to each board. Each board has the 2 or 3 IR receivers and 1 IR LED to communicate the "hit" back to "home."

I'm just trying to come up with a cool design for the gun. I'd like to create it totally from scratch and be a unique design.

TweakGeek: I'm just trying to come up with a cool design for the gun. I'd like to create it totally from scratch and be a unique design.

You could also hunt around at some GoodWill or Re-Stores, or even ebay for broken game console guns and look into retrofitting them with new internals and make them wireless. Nintendo light gun, sega menacer, SUPER SCOPE SIX, or even the Lethal Enforcer "Justifier" light gun.

Keep in mind that these light guns were made for CRT televisions as their targets, so they wont work well or at all with IR, but you can easily replace their internals with the proper equipment, especially if you use a barebones arduino build.

I respect cool and unique, original designs, but i simply squee over nostalgia.

As for the actual communications between target pods and the base station, many many options at all sorts of price ranges.

My current project is a door buzzer system for my motel. When the office door opens, it triggets an arduino to send a signal via an RF transmitter to a remote buzzer unit. The RF transmitter and receiver are 315Mhz units that i got for about $5 each from using VirtualWire. The base has a transmitter, the remote buzzer has a receiver. What is nice is i can build multiple remote buzzer and they all listen for the same signal from the base unit.

If you went this route, you would do the opposite. The remote target pods would have transmitters, and the base would have a receiver. My only consern would be overlapping signals if you have multiple players shooting at the same time. You could make the guns themselves smarter where they report to a base unit, or a sub-base unit that they fired, and then the target reports a hit. If the fire and hit signals are received at roughly the same time, then you would know what player scored a hit. But even then, there could be overlaps.

I wonder if there is documentation available for those old "Laser Storm" arenas that were in malls in the late 90s. They were basically Laser Tag in a dark room with lots of flourescent painted objects to make it look all Tron-like. I remember you had to wear a fannypack of sorts that was connected to the gun. It wasnt an actual laser, because again, that is dangerous.

Researching how Laser Tag / Laser Storm guns/packs worked could help greatly with registering hits and who got what hit.

UPDATE: speak of the devil

One last post before i go to sleep.

A How Stuff Works podcast episode on Laser Tag.

also, some pages i have check out show that the lasers (actual lasers) used in laser tag or laser storm arenas are just for show and for the visual apparance, and are very low power, which would require a person to look directly into the beam for an extended period of time for any damage to happen, as opposed to a laser pointer which would cause damage after only a few seconds.

If you do plan to use LASER-lasers in some way, BE SURE they are the semi-safe low power ones, and now just some laser pen style module.

It's funny you bring up Laser Tag and nostalgia as I happen to have a couple of the black guns around the house here somewhere. I just have to tear the place apart to find them. They are in the garage somewhere.....

Thanks for the help! Gave me more reading to do.

also keep in mind that a laser has pin-point (or, pencil eraser point) precision, and a light sensor is quite small (well, depending on the light sensor i guess), so if you wanted this to be a sniper-style shooting gallery, that would be a good choice. however, if you want it to be a more “in the vicinity of the target”, IR would work a bit better if you can focus the IR light enough to end up being the diameter of a tin can within the “sweet spot / sweet range”.

and just like that How Stuff Works podcast mentions, treat the guns as targets like a Television remote control system. Each gun has a unique IR code/sequence to differentiate each player/gun from one another.