Hello,
I have searched the web for a reliable Arduino long range motion detector.
My project is as follows:
I want to be able to "see" a large object (car, train) coming 25m (90ft) away. I am not interested in the distance, i just want to see it as a PIR would do.
Any help would be greatly appreciated.
If you say "motion detector" and "see", I'm thinking : a webcam with motion detection software. There are many programs and Apps for security, and there are open source libraries for image handling.
Using a laser would probably illegal.
A train that close would cause vibration. You could dig a hole and put an accelerometer in it.
To detect this with an Arduino, I would use a second remote Arduino at the location you want to detect something. Either with a metal detector or a magnetometer. If something is detected, it sends it with a 433MHz module to the main Arduino.
Doppler radar?
Thanx for the replies.
I cannot use vibration because if i have more then one tracks at the location i don't know which train comes.
A motion detecting camera i cannot use with Arduino.
My solution for the time is the sensor at a remote location, and xbee communication because rf is not quite stable, but it is pretty expensive.
Doppler radar... I searched the web for a viable solution, but i havent found a project that worked. If you have any suggestion about the sensor i could use please give me an advice!!
Search Ebay for: "radar motion sensor" or "microwave intelligent switch" or "GH719".
But don't buy the very cheap ones radar sensors, those are radar modules without the electronics.
I think they go up to 10 or 15 meters.
The GH719 are the complete modules. They are up to 10meters.
A PIR sensor detects motion from left to right or right to left, but the radar sensor detect motion towards or from the sensor.
In the early days of burglar alarms I did work with the first Microwave detectors (radar was made in Ireland - ah how things have changed) I could see on the scope a ship moving across the bay - probably 10 K away you just set the sensitivity to what you need and they will give you both NO/NC connections
chip69:
I cannot use vibration because if i have more then one tracks at the location i don't know which train comes.
A motion detecting camera i cannot use with Arduino.
You're introducing new requirements now.
What are you actually trying to achieve, and what are the constraints? For example, do you have access to attach sensors to / near the tracks themselves or does this need to be a purely remote system? What restrictions are there on the packaging? Just because Arduino can't do something, need not mean you can't achieve it by some other means. What do you mean by "see"? Presumably you don't literally mean "see" since you put it in quotes. Are you trying to detect the presence of something? Detect it's size, position, speed, course? Differentiate between that particular type of thing and other similar things (trucks versus trains etc)? So far all you've said is that you want something to behave similar to a PIR sensor, which begs the question why don't you use a PIR sensor?
Sorry for answering so late!
My sensors are in a fixed position near the tracks but i have to sense the train from 15-20m away.
I am not interested in speed just the presence!
The pir can sense only at a limited 7-8m range, and it is too close.
I tried with a magnetometer but i didnt see any change in the magnetic fields from where i was sitting,only when the train was too close to me.
I ordered a xband sensor. It suppose to have a 9+m range. May i can see the train coming from 15m.