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FAQ

Q1: What if apt cannot locate a package?​

E: Unable to locate package ...

A: Run the following command to update the package index, then retry the install.

sudo apt update

Q2: What if the ros2 command is not found?​

ros2: command not found

A: Source the ROS 2 environment with the following commands.

source /opt/ros/jazzy/setup.bash
# If this is a RoboOrchard ROS 2 package, also run:
source ros2_package/install/setup.bash

Q3: What if the can_left device is missing when you need it?​

A: Check CAN devices with the following commands.

# List all recognized devices
ip link

# Check CAN mapping
bash teleop/find-all-can-port.sh

Confirm that the actual CAN devices have been renamed correctly to:

can_left
can_right

Q4: What if the camera has no image?​

A: Check whether the camera is recognized with the following commands.

# First, confirm that the camera is recognized
rs-enumerate-devices

# Then check whether image topics exist
ros2 topic list | grep image

# Then inspect a specific image topic
ros2 topic hz <image_topic>
ros2 topic info <image_topic> -v

Key checks:

  • USB connection is normal
  • USB 3.0 is used
  • Serial Number is configured correctly
  • ROS 2 RealSense driver is running normally

Q5: What if there is a NumPy / OpenCV / SciPy version conflict?​

A: Reinstall the related dependencies with the following commands.

pip install \
    "numpy==1.26.4" \
    "opencv-python<4.11" \
    "scipy<1.14" \
    "numpydantic<1.7"

Q6: How do I calibrate the pose relationship between the left arm and the middle camera?​

A:

  • See the calibration tutorial.
  • Pay attention to the RoboOrchard/projects/HoloBrain/handeye_calib/launch_handeye_calib.sh script configuration.
  • After starting ./launch/start.sh, start the calibration service with bash handeye_calib/launch_handeye_calib.sh.
  • Short-press the button on the robotic arm until it turns green, then move the arm manually to different poses and click Record Current Pose.
  • After recording multiple poses, click Save and Compute Hand-Eye Calibration to save the calibration file to the current path.
  • Required materials: aruco marker and a stand for attaching the aruco marker.