12v magic eye sensor

[s410man]

What would be the proper name for a sensor that i need..

12v input
Needs to trigger a 12v output when something passes with 300mm or so of it
Can't have a pair of sensors either side with a light beam between them needs to be just the one side
Think of a 500mm passageway and i need to trigger a air solenoid to open when something goes down the passageway within say 0.5 seconds

For anyone interested I'm building a air powered sheep clamp for general tasks foottrimming etc but would like it to shut automatically when a sheep runs through so 1 person can use it on their own

Tepari sheep handler on youtube is what I'm making only a slightly simpler version as that one is £25k

 

[Hood]

Optical sensor would be the generic search term I would use.
Something like this maybe?

RS PRO Through Beam (transmitter) Photoelectric Sensor, Barrel Sensor, 10 m Detection Range | RS

uk.rs-online.com

 

[brightspark]

plenty of 12 volt sensors about with a mirror reflector

 

[Hood]

Actually that one won't work as it requires the separate receiver but a search will find the ones you need.

 

[Maker]

It sounds like a PIR sensor is what you're after, the sort of thing you get on floodlights.

 

[Hood]

Is it a one off? May have a sensor here (no guarantees but I have a box of stuff ) but would have to look so won't bother if you need a load of them.

 

[brightspark]

retro reflective censors https://www.google.co.uk/search?q=r...oAEBsAEUwAEB2gEGCAEQARgB&sclient=gws-wiz-serp

 

[500e]

Try
Capacitive proximity sensors

​

 

[Fraserb]

We use plenty of these sensors for scanning when cows walk past, I'll get the numbers from one of them tomorrow.

 

[s410man]

Christ there's some clever people on here ain't there

Ask a random question about a unusual item and within a few hours I've got a list of things to research!

Many thanks all I'm hoping i can find what i need now I've got a clue what they're called!

 

[s410man]

Is it a one off? May have a sensor here (no guarantees but I have a box of stuff ) but would have to look so won't bother if you need a load

I'll see if i can find one... at the moment it's a one off but if i can get it working well enough and cost effective I'm hoping to make a few!

If you had a part number or something would be ace tho if it's not to much trouble to find!

@brightspark they seem to need a reflector to bounce off? I'm hoping to get away with just a sender if possible as the position will be altered fairly regularly and a reciever would have be mounted on the back side which would be awkward to adjust easily

 

[eLuSiVeMiTe]

Christ there's some clever people on here ain't there

Ask a random question about a unusual item and within a few hours I've got a list of things to research!

Many thanks all I'm hoping i can find what i need now I've got a clue what they're called!

That's the problem with the tinternet.

All the information in the world is no good if you don't know what to actually search for.

 

[s410man]

Try
Capacitive proximity sensors

​

Can't seem to find them with a sensing range bigger than about 25mm?

I need 200-400mm sort of range ideally

 

[gaz1]

you dont need power as you can use the sheeps weight to close the gate

 

[Screwdriver]

Passive infrared. Hack a cheapo security light.

 

[Fraserb]

Can't seem to find them with a sensing range bigger than about 25mm?

I need 200-400mm sort of range ideally

The ones we use have a range from about 50mm out to about 2m, there's an Adjuster to set how far away it senses.

 

[Agroshield]

The ones we use have a range from about 50mm out to about 2m...

I think the mode of operation suggested above (capacitive) was the part of the post not quite correct. The longer range ones will be ultrasonic (https://www.motioncontroltips.com/what-are-ultrasonic-proximity-sensors/). A common application is to detect liquid levels in process vessels.

You can buy an Arduino ultrasonic sensor for not much money (https://thepihut.com/products/ultrasonic-distance-sensor-hcsr04) but it won't be 12v and it won't be waterproof. It might be enough to prove the concept.

 

[Bravheart]

As above proximity sensors we had them for switching on/off augers don't think they will be 12v though.















Random thought here, we have a few solar lights in the garden, some with sensors that switch the lights on when you walk past, perhaps that might be the base of a switch if no 12v proximity sensors to be had, will be waterproof anyway, and self powered.





Just need to work on sheep on a good day

 

[Hood]

I'll see if i can find one... at the moment it's a one off but if i can get it working well enough and cost effective I'm hoping to make a few!

If you had a part number or something would be ace tho if it's not to much trouble to find!

@brightspark they seem to need a reflector to bounce off? I'm hoping to get away with just a sender if possible as the position will be altered fairly regularly and a reciever would have be mounted on the back side which would be awkward to adjust easily

I have one of these, which I think would do but you would have to check the data sheet.

 

[Hood]

All the rest I have are either through beam (need transmitter and receiver opposite) or reflective type.