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Daylight Sensor for IR HUD (or anything else)

solar panel into a small motor, with a torque sensor on it, rps from the sensor to a mcu.. if rps greater than .01rps, output an on signal to toggle IR mode.. and a toggle switch.. then you can use the toggle switch to turn on nonIR daymode if you want for zooming or whatever.. otherwise it automatically turns on IR

minimum effort daylight sensor.

I think I tossed a cap in the mix as well in the MCU, which would need tuning to get it to trigger on at sunset and off at sunrise properly.
A larger panel may be more effective but I wanted to see if it'd work with the smallest panel.