perhaps notable project: Thermal camera on internet controlled robot

[efeuentertainment]

feel free to try the thermal camera and robot «CakeOnIce» (online during GMT day) on https://vigibot.com
Note: I'm only a user of the Vigibot project.

Same text in forum post https://www.robot-maker.com/forum/topic/14770-thermal-camera-on-internet-controlled-robot/

1729602622182_firened_CakeOnIce.mp4

I got the infiray p2 pro thermal camera.
connected to PC it works like a webcam.
it recalibrates every 10s with an audible click, so i needed a way to turn it off when not in use.

i used uhubctl from https://github.com/mvp/uhubctl?tab=readme-ov-file#raspberry-pi-4b
off:

sudo uhubctl -l 1-1 -a off
sudo uhubctl -l 2 -a off

all 4 usb are switched together, turning off the usb microphone meant restarting the vigibot client every time.

fortunately the 4B allows usb host on the "power in" type c, to which i connected the microphone to keep it powered. otg_mode=1
https://forums.raspberrypi.com/viewtopic.php?t=246348

wrote a script vim thermal_power_manager.sh:

#!/bin/bash                              
# Function to handle cleanup on SIGTERM
cleanup() {
    echo "Stopping FFmpeg process..."
    kill $ffmpeg_pid
    wait $ffmpeg_pid 2>/dev/null

    echo "Disabling power to USB hub and thermal camera..."
    uhubctl -l 1-1 -a 0 > /dev/null
    uhubctl -l 2 -a 0 > /dev/null
    exit 0
}

# Enable power to USB hub and thermal camera
echo "Enabling power to USB hub and thermal camera..."
uhubctl -l 1-1 -a 1 > /dev/null
uhubctl -l 2 -a 1 > /dev/null

# Start FFmpeg stream
sleep 2
echo "Starting FFmpeg stream..."
ffmpeg -loglevel warning -i /dev/video1 -c:v h264_omx -profile:v baseline -b:v 1500000 -flags:v +global_header -bsf:v dump_extra -f rawvideo -vf 'scale=640x480' tcp://127.0.0.1:8043 &
ffmpeg_pid=$!

# Trap SIGTERM signal and execute the cleanup function
trap cleanup SIGTERM SIGINT

# Wait for the FFmpeg process to finish
wait $ffmpeg_pid

# Disable USB hub power for thermal camera after ffmpeg exits
uhubctl -l 1-1 -a 0 > /dev/null
uhubctl -l 2 -a 0 > /dev/null

echo "Stream stopped and USB power disabled."
exit 0

[efeuentertainment]

Thank you mvp for uhubctl ♥️