08/19/2018 at 07:22 •
The goal here was to capture images intermittently and reduce power consumption. The following stats are all for a headless, HDMI disabled, RPi Zero W connected via SSH on Wifi. This is using a Purethermal 2 board and a Lepton 3.5 Here are the results:
- 0.098 A - Idle and purethermal2 is unplugged
- 0.175 A - Idle, now the purethermal2 is plugged in
- 0.340 A - There is always a brief spike when the shutter operates
- 0.250- 0.300 A- When running script that streams constantly from camera
- 0.185A for 9 seconds, 0.240A for less than 1 second @ when running script that takes output every 10 seconds
Using exactly the same setup and a Lepton 2.5, the results are almost exactly the same, except it seems like the peak current is a little less ( ~0.23A) and duration of the higher current for running is also less.
08/15/2018 at 14:28 •
I will do this on a headless Rpi Zero W.
First I am going to install a headless Raspian Stretech lite. Directions for this are here:
Next I will setup the software for the Purethermal2 to work with the RPi. I will first install libusb and then the groupgets version of libuvc (https://github.com/groupgets/libuvc) and then I will try the uvc-radiometry.py script from (https://github.com/groupgets/purethermal1-uvc-capture).
Once I get the image capture to work, we will save power by periodically disconnecting from and turning off the Purethermal board which is a usb device. There are some forums that discuss generally how this is done:
Another approach would be to work on doing a better job at stopping camera streaming when we are done.
General power saving tips are discussed here.