Hi I'm looking to start my first arduino project and im looking for some advise in regards to what sensors to use.
i want to be able to detect a person between 5-10m away in the dark when a person passes directly in front of the sensor. This will then trigger an led to show a person has passed the sensor
i was thinking of using a pir sensor and placing it in some tubing to restrict its detection angle from 120 degrees to about 10. This may work but i have been reading that they only detect changes in temp so if a person stays in from of the sensor it will stop detecting them until they move.
if anyone has any ideas of any better sensors it will be a great help
The end goal is to create a sentry searchlight that will be placed on the ground in a middle of a room and scan back and forth an arc of about 120 degrees while playing Airsoft indoors.
The environment will be dark, fairly cold ~10c and dry with little heat sources other than players so basically so if it is pointed toward to other team any heat source is a target.
When it detects a person i presume via some sore of IR sensor it will stop and activate some LEDs to light up the person so they can be spotted as typically indoor games can be extremely dark and using a torch your self just screams 'Shoot at me i'm over here!'
if possible it then track them if they then move from there original location (left/right) all of this i think could be done using pir sensors if it hard 3 attached to over left,right and ahead as far as im aware
i would also like it to be able to detect if the person has been detected and stays in there original position. i know this may be a problem for pir sensors as they detect changes in temp rather than a temp range.
This would mean if they stayed in position there would be a chance the pir would not trigger again....i dont know if once triggered it could entered a loop where the servo would loop back and forth about 5-10 degrees from its detection location in order to try and re trigger its self if they are still in the same location
how would a laser trip wire work? would that require a transmitter and a receiver to be placed at 2 locations or some thing reflective enough to bound the IR from the transmitter to the receiver?
Look into using webcams with something like a raspberry Pi, or any linux PC.
Players would have IR LEDs (1+) installed on them. There is already image proccessing available on RPi to detect the IR Leds within the image in real-time.
Having 2 cameras placed @ 90 degrees (adjacent walls/ceilings) would allow you to triangulate the position of each person in the room in real time. (essentially you end up with an image with just white(IR) blobs)
Similar projects have been published using the wii remote or kinect for electronic whiteboards.
....could be a really fun project
Another approach could be to have an IR LED in headgear and have the room divided into grids and have the sensors looking down & only into their own grid (1mx1m?). This approach could work with an arduino alone. Another benefit is that you could ID each player as well. Difficult bit would be to restrict scope to each grid...but doable.
