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Is a laser operated button pusher possible? Answered

We have a business convention coming up soon. Inside of our display case we have this grid of LED panels. The goal of the display is you try and hit a button outside of the case when a certain LED panel is lit To demonstrate human vs. computing reflexes. I'd like to have some kind of external build to demonstrate with as the "vs.".

I am thinking I can use a laser and point it at the LED block because lasers are capable of transferring data. I would think it wouldn't be too difficult to make a build that distinguishes between on & off. It's basic binary, on & off 1 & 0, true & false, same & changed. When the surface lights that the laser is pointed on, I think the easiest way to push the button would be to discharge a capacitor into a hobby motor, and some kind of tab or something on the motor. I can go into more detail on the build, but I need more info on making a laser operated trigger system thingy.


Well your easiest way is to plug the computer into the matrix (but that would be a "duh?" type of thing)

You could probably do it with a video camera and the right software.


The thing with taping into the matrix is I can't get any wires out of the display case for an external unit to change over from a computerized mode to a player. I'd have to keep opening the case to switch the player on & off, & I don't have the authority (we only have one key *facepalm*) so I'd have to keep running off and getting the guy with the key, who isn't completely on board with the idea in the first place. I would otherwise, but I didn't design the case. The case was made for security, it has power supplied inside. (for the same reason, it's not good with heat, a lack of ventilation) This is a very acceptable solution if you could point me in the direction of some software, and a general idea of how to make the computer set off a motor. I have a small digital camera that I could run as a web cam. I could run it into a netbook or laptop. (give me a chance to display my awesome desktop I make too :D) I can zoom it into the LED, so it takes up whole whole screen. With this setup, I would now be looking for a way to make the laptop trigger a motor, which I am equally clueless on how I would do that. I can bring the video from the camera feed on screen, and I'm sure SOMEWHERE there is a program that can detect a color change within a given parameter. (I know these kind of programs exist because I used to mess with them on my old PC games back in the day) The only problem now is getting a program to do something externally, rather than type a command, or just click the color. I'd have no idea how to edit a program, or create a new one.

Thing is, detecting a laser spot, through a glass window, and in an exhibition light is NOT trivially easy. You still haven't said how long you have to do this in.

You could trigger "Player" by using your laser to hit an invisible target in the case, it switches to player mode until no-one shoots the game for 20 seconds or so, then it reverts back to demo. Steve

I have a good solid month or more in which to accomplish this in. There is a button to stop the game out side of the case (the button has designed as a 'play' button to start a video. I kindof repurposed it... The problem with letting it go into a demo mode after so many seconds is there is no proof that it is not one machine. The goal here is to compare human Vs computer reflexes. I kind of like L's idea of using a camera, and I think it would be much easier to do. But since this is tagged in lasers, the thread should stay more or less on track.I'm starting to come to the realization that, as simple as the layout sounded in my head, an actual build is going to be a bit implausible...

An actual build is going to be a bit implausible...

Yes, I think its a bit too ambitious, and image recognition even more so.

I don't know, with an image recognition, all I'd need to do is take a recording before hand, mess with it on a PC until I get a few reliable color hexs out of it. Thanks to a lovely set of halogen lights, the colors shouldn't change through the day, they should stay constant. I could even tear down a printer, or a CD drive for something to command, anything with moving parts, I just need a quick jerk out of it.

Although, connecting the movement with the cues, again that brick wall.

"First stage - collect underpants.
Second stage - ???.
Third stage - profit.
Get it?"

Thanks for your help

"This is a very acceptable..." Was a new paragraph, relating to the second method you had explained, but instructables didn't keep my formatting.

So, you want to shoot the led block with the laser and identify the shot block ?

You need a laser you can modulate an audio tone into. What colour are your LEDs ? If the laser is strongly the same colour, the LED makes a pretty good detector, with the right electronics around it, even when its lit. Failing that, you could sneak plastic optical fibres between the LEDS and onto some photodiodes. How long have you got to do this crazy thing in ? Steve