Walker S2 EDU: Wrist Camera (RealSense D405)

ubt_IL/walker/realsense_wrist_camera/: an Intel RealSense D405 wrist camera ROS 2 publisher that provides wrist vision input for Walker S2 EDU real-robot deployment.

Quick start

# 1. Install (auto-discover cameras, generate config, persist PATH)
bash /ubt_IL/walker/realsense_wrist_camera/scripts/install.sh

# 2. Start (runs in the background by default)
bash /ubt_IL/walker/realsense_wrist_camera/scripts/start.sh

# 3. Check status / stop
bash /ubt_IL/walker/realsense_wrist_camera/scripts/start.sh --status
bash /ubt_IL/walker/realsense_wrist_camera/scripts/start.sh --stop

For debugging, run in the foreground with bash start.sh --fg; other arguments are passed through to the CLI (e.g. bash start.sh --fg --discover).

Verify publishing

ros2 topic echo /sensor/camera/wrist_right/color/raw --once --qos-reliability best_effort

Configuration

install.sh generates configs/wrist_cameras.json automatically; regenerate it with:

find-realsense-cameras

Start with an explicit config:

realsense-wrist-camera --config /path/to/cameras.json &

Config format (one D405 per wrist, shm_msgs/Image1m, 640×480@15fps):

{
  "cameras": [
    {
      "serial": "261122273724",
      "topic": "/sensor/camera/wrist_right/color/raw",
      "msg_type": "shm_msgs/Image1m",
      "frame_id": "wrist_right",
      "width": 640,
      "height": 480,
      "fps": 15
    },
    {
      "serial": "261022273252",
      "topic": "/sensor/camera/wrist_left/color/raw",
      "msg_type": "shm_msgs/Image1m",
      "frame_id": "wrist_left",
      "width": 640,
      "height": 480,
      "fps": 15
    }
  ]
}

Integration with real-robot deployment

The wrist cameras publish shm_msgs/Image1m on standard topics; walker_camera_relay.py picks them up automatically, so rollout needs no extra configuration:

# Terminal 1
bash /ubt_IL/walker/realsense_wrist_camera/scripts/start.sh

# Terminal 2 - normal rollout
POLICY_PATH=/ubt_IL/model/<policy>/checkpoints/080000/pretrained_model \
bash /ubt_IL/scripts/deploy/walker_s2/rollout.sh

Installation prerequisites

udev rules (host, one time):

sudo sh -c 'echo "SUBSYSTEM==\"usb\", ATTR{idVendor}==\"8086\", ATTR{idProduct}==\"0b5b\", MODE=\"0666\"" > /etc/udev/rules.d/99-realsense-d405.rules'
sudo udevadm control --reload-rules
sudo udevadm trigger

Docker: the container must run with --privileged (already included in the project run.sh).

FAQ

Symptom	Fix
No RealSense devices detected	Check the USB connection and udev rules
ModuleNotFoundError: pyrealsense2	Rerun install.sh
ModuleNotFoundError: rclpy	source /opt/ros/humble/setup.bash
USB Permission denied	Docker is missing --privileged