Non-heat based motion detection

Hello,

I am looking for a non-heat based motion detection for a foosball goal counter (when ball goes inside a goal). I was recommended http://www.ebay.com/sch/i.html?_nkw=TCRT5000. Are there any alternatives available to be ordered from UK? I wouldn't mind a sensitive switch either, but havent really found any available in the UK.

Project has been kind of stuck on this so any help is really appreciated!

Cheers

Fox

The TCRT­5000 seems to be available from the UK - just go to ebay.co.uk, type in TCRT­5000, and click 'UK Only' under 'Item location'.

Only thing I'd say with those sensors is they're reflective. I'd be tempted to just cut them in half, and have one half on one side of the goal, one half on the other. That way you'll have a 'beam' - and when the ball cuts that beam then it'll be really easy to see.

You could use just the TRCT5000 single device on its own with Espruino and a resistor, but as the modules (with PCB) aren't very expensive and also have an adjustment for sensitivity, maybe use them?

It's slightly more difficult to split the TRCT5000 in two, but not too hard...

Yeah - those are opto sensors, which is what you'd probably want to use. They also make ones that have two parts, and you put them on each side of the area where things pass though to detect when something blocks the light between them.

Just to add that you could probably use a simple LDR in a black tube to block out ambient light, and an LED.

IR obviously has the bonus that you can't see it, but for extra geek cred you could use a laser (pointer) instead :)

Hey guys, cheers for the incredibly quick comments.

1) Regarding TRCT5000. It says that the sensitive range is just 12mm, is that real world? I would need to around 5 - 7cm. It's not gonna be mounted on the goal, but in a drain behind it, so the goalie does not intefere with it. And yeah, I was thinking about splitting them in two.

2) What are PCB modules? :)

Thanks

Fox

PCB is printed circuit board, a PCB module is a small PCB with a part and supporting components mounted

For that distance, yeah, you need an opto switch that comes in two parts. The ones you mentioned work only at a much shorter range.

Thanks. Can you recommend anything? Or should I use the light dependent resistor with a LED or similar?

They use an ir led and photodiode like the one you linked only not stuck to each other

Don't know a part number but they exist. I see em all the time taking stuff apart

I had a quick look and can't see anything on eBay at the moment, short of 'flame sensors' that might work I guess.

Best bet would be to buy one of these and to then unsolder the transmitter part (the light blue LED) and mount it on the other side of the goal.

OR... maybe leave that module as-is and just put a small mirror on the other side of the goal? That'd be nice and easy. All you're trying to do is reflect the light from the IR LED back into the sensor.

Those TRCT devices work using reflection, so on a normal white surface they'll only go to a few cm - however if you point the IR LED right at the sensor, or have something properly reflective like a mirror (aimed correctly) they should work over pretty large distances.

That one looked the best to be honest so I ordered it. Should be with me on Friday. We will proceed using the mirror on the other side, as it sounds as the most sophisticated way.

Thanks, back to you on Friday! :)

beyond 15mm maybe you'll not have enough collector current. So you won't see any switching at the output.