IR Watchdog : Initial Tech Specs

[nelsonii]

"It's a smoke alarm for IR" -- this is NOT a medical device NOR a redundant solution. The idea is to alert caregivers when "the eye gaze accidently gets unplugged" etc. It is NOT an eye tracker.

General Requirements

1. Repeatable (easy to source parts).
2. Inexpensive (<$100).
3. Easy to use (no fancy UI).

Initial Tech Thoughts

1. Use the IR board that Chris and Bill have developed, with a QT Py as the microcontroller, for prototype.
2. The design will be such that it can be re-created WITHOUT any custom PCBs -- for folks who can't get them. Should be point-to-point wiring friendly.
3. It will be powered by USB. I think having a battery backup would be nice to have, but high on the list.
4. Use a different/custom board for the actual device? I really want battery backup, so we may want to go with boards that have that on-board.
5. Device will look for IR (there are questions about this in the Issues list). When IR goes away, provide audio and visual alert. I'm thinking buzzer/beep and a bright LED to start with.

Future Tech Thoughts (Cool Improvements)

1. Use a microcontroller which supports WiFi and have it send alerts out.

[ImproveAbility]

I think this is an intriguing idea. There was a period of time where we were having some relatively consistent issues with cameras disconnecting. This device would work in that situation. I am currently dealing with an issue with Grid Pads right now that does have camera disconnect, so this is not a device that would detect all issues with an eye gaze system, but it is something that would be super useful.

[nelsonii]

Yep. Another tool for our toolbox. I'm thinking primary use is "eye gaze system turned off" (because, it might lock up, but still transmit IR).

This is a completely passive sensor -- it emits nothing, so it won't mess with equipment.

[ImproveAbility]

Question - how does the receiver "see" the IR - what kind of sensitivity does it have? Where would it have to be positioned in order to pick up the IR from the camera?

[nelsonii]

There is a photodiode that looks for IR. It's a line-of-sight sensor which picks up IR, but doesn't try to "decode" it.

This waveform image was measured from across the room, pointing a TV remote at it. (Tobii/etc would use similar illumination.)

The device can be mounted behind the user, with a view of the eye gaze -- the sensitivity is just like you get with a TV remote.