Pi Camera UDP Server | Camera-things

This is a repository for a camera server that runs on a Raspberry Pi Zero 2 W and sends images to a Jetson Orin Nano via UDP.

Dependencies

• Raspberry Pi Zero 2 W
• Jetson Orin Nano
• Micro-USB to USB-A data cable

Quick Setup

1. Setup the Networking Connection
2. Then setup the codebase below:

git clone git@github.com:tritonuas/camera-things.git
cd camera-things

# Install dependencies
sudo apt update
sudo apt install -y \
    build-essential \
    cmake \
    pkg-config \
    libcamera-dev \
    libevent-dev \
    libusb-1.0-0-dev

# Build the project
mkdir build && cd build
cmake ..    # configures the CMake build system
make

# Run the server
./raspy

Config Files

The server uses one config file config/picam.json.

{
    "UART_NAME": "/dev/serial0",    // UART port to use for MAVLink communication
    "BAUDRATE": 57600,              // Baudrate for MAVLink communication
    "DEBUG_MODE": 1,                // 1 for debug mode, 0 for normal mode
    "SEND_TO_OBC": 0,               // 1 to send images to OBC, 0 to send to Jetson
    "MAVLINK_ENABLED": 1            // 1 to enable MAVLink communication, 0 to disable
}

Network Setup

1. Enable USB Gadget Mode & Set Static MAC

We need to load the necessary kernel modules and force a specific MAC address so the Jetson always recognizes the Pi as the same device.

1. Open config.txt:

   sudo nano /boot/firmware/config.txt

2. Add this line to the very bottom:

   dtoverlay=dwc2
   

3. Save and exit (Ctrl+O, Enter, Ctrl+X).

4. Open cmdline.txt:

   sudo nano /boot/firmware/cmdline.txt

5. Find the line of text. Do not create a new line. Add the following text strictly after rootwait:

   modules-load=dwc2,g_ether g_ether.host_addr=00:dc:c8:f7:75:14 g_ether.dev_addr=00:dd:dc:eb:6d:da
   

   Make sure there is a space before and after this addition.

2. Configure Static IP (192.168.77.2)

We configure NetworkManager to assign a static IP to the usb0 interface.

# Create the connection profile
sudo nmcli con add type ethernet con-name "usb-gadget" ifname usb0

# Set Static IP
sudo nmcli con modify "usb-gadget" ipv4.addresses 192.168.77.2/24
sudo nmcli con modify "usb-gadget" ipv4.method manual

# Disable IPv6 to reduce overhead (optional but recommended)
sudo nmcli con modify "usb-gadget" ipv6.method ignore

3. Add Crontab "Kickstarter"

To ensure the network comes up reliably on every boot, we add a cron job to force the connection.

1. Open crontab:

   sudo crontab -e

2. Add this line to the bottom:

   @reboot sleep 30 && /usr/bin/nmcli con up "usb-gadget" > /var/log/gadget_connect.log 2>&1
   

3. Reboot the Pi: sudo reboot now

---

4. Physical Connection & Testing

1. Connect the Hardware

1. Plug the Micro-USB end into the Data Port of the Pi Zero 2 W (the port labeled "USB", closest to the center).
2. Plug the USB-A end into the Jetson Orin Nano.

2. Verify Connectivity

Wait about 45-60 seconds after plugging in (for the Pi to boot and the Crontab job to run).

On the Jetson:

# 1. Check if the interface exists
ip link show
# Look for an interface with MAC 00:dc:c8:f7:75:14

# 2. Ping the Pi (we should see the packet returning)
ping 192.168.77.2