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#206946
Hello, from way up north in FoCo! lol

I saw your RFID reader, and was hoping to pick someone's brain about it. I have an idea to use the reader as a timing device for drone racing, and I want to clarify some of its capabilities before pulling the trigger. In my mind, the ideal situation would be the reader with an external antenna at the start gate, being able to reliably read a tag thats as small as possible on the drones, and be able to read them from varying angles and what not. My mission is to figure out, is this reader capable if this task, and what "stuff" I'd need to make that happen, so a shopping list and any other support would be GREATLY appreciated.

So, some questions about the reader...

Firstly, is the word "simultaneous", in conjunction with the 150 reads per second claim. The most demanding conditions for these races would be as many as 8 drones simultaneously going through a race gate at 110fps/75mph or so. This isnt incredibly likely, but to appease some of the more picky pilots, I want to be sure of its capabilities. More than likely, it would be more like 2 or 3 quads at once maybe doing more like 40mph.

Would it read them all at the same time, or does there need to be a small amount of time between reads? The reason I ask, is at the "worst" case speed of 75mph, and an assumed external antenna "cone" dia at the gate of 5ft (the size of the gates typically), that gives a window of about 45ms to charge and read the tag, if the antenna is more or less above the gate on a tripod or something. Is this thing going to be able to handle that? Ideally it would be able to actually read simultaneously, but if a time gap of say 6 to 14ms is required, that is close enough in my book for "simultaneous". If its more than that, it would more than likely still work, I just wasn't able to definitively figure that out from the available information. The video demonstration with the frisbee is what lead me to believe it would be fit for purpose.

Which leads to my last question: Is the 150 reads per second a full charge/read cycle of a passive tag? So the functional read rate is more like 75 per second? Or is it a full read of a tag at 150 per second?

Sorry for the huge post, I just got super excited about this idea when I started looking at this reader and would love to see it to fruition!

Thank you so much for your time and help!
-Travis
#206994
Hi, I am working on a similar project but for my PE colleagues to time their students in cross country.
In your case, based on the experiments I have made already, getting active tags might be necessary as the speed of the drones is quite high.
The passive tags receive their power from the antenna and if it passes by too quickly, the reading can be missed.

My first tests while walking/running are sometimes missed and I am considering getting a dual antenna to avoid this but I am not sure yet if it will be necessary.

The second big issue (and I am about to post a specific message about it) it is hard to filter the data received straight in Arduino.
You may receive the same TAG ID 20 times instead of one and so far all the tries I have made have failed to filter the data received.
To fix it, I am using the PLX-DAQ Excel spreadsheet and deal with the data in Excel which seems to be working efficiently enough so far.