RFID locator for a range up to 30 ft


#1

Hi,
I know, my question is not really related to biohacking things, but you all are always so helpful and kind, so I simply hope you can help me with my project:

Basically I try to find a solution for locating lost arrows (archery). I thought about infrared leds with an infrared camera (or simply a camera without IR filter), I thought about a similar solution with UV, and came along to RFID (since I found an RFID locator for golf balls).

The issue is the physics of an arrow: Thin, carbon or aluminium, and weight and balance is definetely an issue.
A glass tube would fit great. But with passive RFID I won’t get results out of a range of some inches.
The target is to find arrows at least in 10 meter (30 ft) radius, so here are my questions:
Do you know any tube-like active rfid-transponders with a very small and light battery? Or any other form factor which could fit into the inner space of an arrow? And do you know any device to track them? Measuring the field strength could be enough to find the arrows…

Or any other ideas?

Thank you all for your input!
Best, Wolfgang


#2

In theory and under ideal conditions, UHF RFID tags could be read at that range. But it’s not easy and requires quite a bit of power, along with a large directional antenna. The tags are stickers similar to this:

I don’t know how well the would work (or stay) wrapped around an antenna. And read range would be significantly reduced if you are not hitting the tag broadside with your rf field.

I don’t know much about archery, but it would seem any sort of on-board electronics that require a battery would effect the flight characteristics and would have to be inegrated into the design of the arrow from the start for it to be feasible.

How about florescent paint and a black light or UV laser? That would require line of sight though…

Might look into building a very simple AM transmitter beacon that “chirps” every few seconds.

Or maybe just hit your target more often. :joy:

If you are looking for them right away… Keep your arrows in a warmer (or cooler depending on the surrounding temps). Then use an IR camera to locate the warm arrows against the background.


#3

You’re not going to get any sort of range with passive RFID, but given that they make battery powered lighted nocks you could probably figure out a way to put an active transmitter in the nock and find it with a small direction finder like the the golf balls or like those little BT Key trackers.


#4

Thank your for your quick replies, I appreciate.
In the meantime I’ve found batteries (originally from fishing) with LEDs which fit into the inner space of arrows for sure.
The idea now is, to replace the colored LEDs with pure white LEDs and additionally use golf finder goggles (which filter out all colors except white). I’d imagine, the white LED would boost the effect of those goggles. At least this is a quite cheap way for the first try!

And if this try fails, I’ll come back to I0TA probably, since the battery could used for active RFID technology probably very easy.
Thank you all!