SelfWeigh

Weighbridge HMI/kiosk with PlateRecognizer ANPR and Google Drive integration

Requirements

This has been tested and currently used on Raspberry Pi 4 with Raspbian 10 (with desktop) with Python 3.7.3. For a basic setup, you will need at least one Raspberry Pi, and at least one IP camera with JPG snapshot or RTSP video stream support.

Hardware

• Weighbridge unit with RS232 output
  • Tested with Avery Weigh-Tronix E1205
• USB to RS232 adapter with Prolific PL2303 chip
• Raspberry Pi 4 with MicroSD card
• RPi-compatible touch screen LCD (resistive touch recommended, especially for outdoor units)
• At least one IP camera with IR support
  • Current version supports up to 4 cameras
• Thermal POS printer
  • Tested with Naviatec (Zjiang) 5890T
  • CUPS support required for QR-code printing
• Optional: 1-2 additional RPi-s with touchscreens for outdoor units

Installation & Configuration

Flashing SD card(s)

Download 32-bit Raspberry Pi OS (Legacy) 10 with desktop image.

Flash the downloaded image to SD card(s) with a flashing tool, such as balenaEtcher.

Installation

Once you've set up and booted up Pi, install the necessary packages and Python modules:

sudo apt install git tee sshfs ser2net socat moreutils python3-{pip,tk,pandas,opencv}
python3 -m pip install serial pydrive urllib3 requests expect ping3

Clone this repo to ~/SelfWeigh dir and make the necessary files executable:

mkdir ~/SelfWeigh; git clone https://github.com/elveos/SelfWeigh.git ~/SelfWeigh
cd ~/SelfWeigh/
find ~/SelfWeigh/ -type f \(-name "*.sh" -o name "*.py \)" -exec chmod +x {} \;

Configuration

Make sure that each Pi and camera is using static IP or a hostname.

Enable the SSH server by following Raspberry Pi Documentation.

Enter your Google API Client ID and Client Secret to settings.yaml.

Complete the necessary configuration in settings_main.py.

Change the screen resolution to 800x480:

tee -a /boot/config.txt <<EOF
hdmi_group=2
hdmi_mode=87
hdmi_cvt=800 480 60 6 0 0 0
EOF

Main unit configuration

Enable serial port over TCP sharing on the main unit only:

echo "3333:raw:0:dev:/tty/USB0:9600 8DATABITS NONE 1STOPBIT max-connections=5" >> /etc/ser2net.conf
systemctl restart ser2net.service

Make SelfWeigh start on boot:

cp ~/Projects/SelfWeigh/selfweigh-autostart.desktop ~/.config/autostart/selfweigh-autostart.desktop
chmod +x ~/.config/autostart/selfweigh-autostart.desktop

Configuration for outdoor units only

Generate SSH keypair on outdoor unit and copy it to main unit:

ssh-keygen -t rsa -N "" -f ~/.ssh/id_rsa
ssh-copy-id pi@<remote-unit-ip>

Set the main unit's IP/hostname in launch.sh:

sed -i 's|MAIN_UNIT_IP="empty"|MAIN_UNIT_IP="main-unit-hostname.lan"|g' launch.sh

Make SelfWeigh start on boot:

sudo cp ~/Projects/SelfWeigh/selfweigh_outdoor-autostart.desktop /etc/xdg/autostart/
chmod +x /etc/xdg/autostart/selfweigh_outdoor-autostart.desktop

To Do

Add usage documentation Add main.py for outdoor units or merge it into main_server.py as universal script

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License

This project is licensed under the GNU General Public License version 3 (GPLv3). You can find the full text of the license in the LICENSE file.