ROS 2 Humble Setup Guide (Ubuntu 22.04 LTS)

I. ROS 2 Humble Setup or run

    ./install.sh

1. Set Locale

Before installing ROS 2, ensure your system locale is set to UTF-8.

locale  # check for UTF-8

sudo apt update && sudo apt install locales
sudo locale-gen en_US en_US.UTF-8
sudo update-locale LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8
export LANG=en_US.UTF-8

locale  # verify settings

2. Setup Sources

To add the ROS 2 apt repository, enable the Ubuntu Universe repository.

sudo apt install software-properties-common
sudo add-apt-repository universe

Add the ROS 2 GPG key with apt.

sudo apt update && sudo apt install curl -y
sudo curl -sSL https://raw.githubusercontent.com/ros/rosdistro/master/ros.key -o /usr/share/keyrings/ros-archive-keyring.gpg

echo "deb [signed-by=/usr/share/keyrings/ros-archive-keyring.gpg] http://packages.ros.org/ros2/ubuntu $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/ros2.list > /dev/null

sudo apt update

3. Install ROS 2 Packages

Update your apt repository caches and install ROS 2 packages.

sudo apt update
sudo apt upgrade

sudo apt install ros-humble-desktop

Install development tools.

sudo apt install ros-dev-tools

4. Environment Setup

To start working with ROS 2, source the setup script in each terminal session.

source /opt/ros/humble/setup.bash

5. Try Some Examples

Talker-Listener Example

Open a terminal and start a talker node:

source /opt/ros/humble/setup.bash
ros2 run demo_nodes_py talker

Open another terminal and start a listener node: ✅

source /opt/ros/humble/setup.bash
ros2 run demo_nodes_py listener

II. OpenCV 4.8.0+ Installation for Librealsense

# Install dependencies
sudo apt update
sudo apt install -y build-essential cmake pkg-config libjpeg-dev libtiff-dev libpng-dev libgtk-3-dev libcanberra-gtk* libatlas-base-dev gfortran python3-dev

# Download OpenCV
wget -O opencv.zip https://github.com/opencv/opencv/archive/4.8.0.zip
unzip opencv.zip
cd opencv-4.8.0

# Build OpenCV
mkdir build
cd build
cmake ..
make -j$(nproc)
sudo make install

III. Camera Node Setup

** Realsense SDK Install

cd ~
git clone https://github.com/IntelRealSense/librealsense.git
cd librealsense
sudo cp config/99-realsense-libusb.rules /etc/udev/rules.d/
sudo udevadm control --reload-rules && sudo udevadm trigger
mkdir build && cd build
cmake .. -DFORCE_RSUSB_BACKEND=ON -DBUILD_EXAMPLES=true -DCMAKE_BUILD_TYPE=Release
make -j$(nproc)
sudo make install
sudo ldconfig

1. Clone the realsense_ros Repository

git clone https://github.com/IntelRealSense/realsense-ros.git
cd realsense-ros
colcon build --symlink-install

2. Source the Workspace

Source the newly built workspace:

source ~/realsense-ros/install/setup.bash

To make it persistent, add it to your .bashrc:

echo "source ~/realsense-ros/install/setup.bash" >> ~/.bashrc

3. Launch Camera Node (downfacing)

To test the installation, launch the RealSense camera node:

ros2 launch realsense2_camera rs_launch.py   enable_depth:=true   enable_color:=true   enable_sync:=true   depth_module.depth_profile:=848,480,90   rgb_camera.color_profile:=848,480,30 enable_sync:=true enable_gyro:=true enable_accel:=true unite_imu_method:=2 gyro_fps:=200 accel_fps:=200

IV. RTAB-Map Installation

1. Install RTAB-Map

sudo apt install -y ros-humble-rtabmap-ros

2. Launch IMU node:

ros2 run imu_filter_madgwick imu_filter_madgwick_node   --ros-args   -r imu/data_raw:=/camera/camera/imu   -r imu/data:=/imu/data   -p use_mag:=false

3. Launch RTAB-Map

ros2 launch rtabmap_launch rtabmap.launch.py   rtabmap_args:="--delete_db_on_start"   rgb_topic:=/camera/camera/color/image_raw   depth_topic:=/camera/camera/depth/image_rect_raw   camera_info_topic:=/camera/camera/color/camera_info   frame_id:=camera_link   use_sim_time:=true   approx_sync:=true   qos:=2   rviz:=false   queue_size:=100 imu_topic:=/imu/data

4. Ardupilot Parameter setup (Camera Downfacing)

SERIAL1_PROTOCOL = 2 (MAVLink2).

SERIAL1_BAUD = 115 (115200 baud)

VISO_TYPE = 1 (mavlink)

EK3_SRC1_POSXY = 6 (ExternalNav)

EK3_SRC1_VELXY = 6 (ExternalNav)

EK3_SRC1_POSZ = 1 (Baro which is safer)

EK3_SRC1_VELZ = 6 (you can set it to 6 if 1st flight test looks good)

EK3_SRC1_YAW = 6 (ExternalNav)

5. Run Slam node (ardupilot)

# (downfacing camera) #need rangefinder for better position hold
python3 slam_localization_ekf.py #up to date

# for forward facing camera
python3 slam_localization_frd.py 

# for cpp run
colcon build --packages-select slam_localization --symlink-install #once
source install/setup.bash #once
ros2 run slam_localization slam_node #updated
 

6. To see Saved maps Run

rtabmap ~/.ros/rtabmap.db

IV. Stereo Slam with RTABMAP

1. Stereo SLAM

1. Launch camera with infra1 (left) and infra2(right)

# realsense launch command
ros2 launch realsense2_camera rs_launch.py enable_infra1:=true enable_infra2:=true  enable_color:=true   enable_sync:=true  rgb_camera.color_profile:=848,480,30 enable_sync:=true enable_gyro:=true enable_accel:=true unite_imu_method:=2 gyro_fps:=200 accel_fps:=200 depth_module.infra_profile:=848,480,90

# Zed2i launch command 
ros2 launch zed_wrapper zed_camera.launch.py camera_model:=zed2i enable_ipc:=false ros_params_override_path:="/home/deathstroke/zed_conf.yaml"

2. Launch IMU Node :

ros2 run imu_filter_madgwick imu_filter_madgwick_node   --ros-args   -r imu/data_raw:=/camera/camera/imu   -r imu/data:=/imu/data   -p use_mag:=false

3. Launch RTABMAP for stereo

#rtabmap with realsense
ros2 launch rtabmap_launch rtabmap.launch.py \
   rtabmap_args:="--delete_db_on_start" \
   stereo:=true \
   left_image_topic:=/camera/camera/infra1/image_rect_raw \
   right_image_topic:=/camera/camera/infra2/image_rect_raw \
   left_camera_info_topic:=/camera/camera/infra1/camera_info \
   right_camera_info_topic:=/camera/camera/infra2/camera_info \
   frame_id:=camera_link \
   use_sim_time:=true \
   approx_sync:=true \
   qos:=2 \
   rviz:=false \
   queue_size:=100 \
   imu_topic:=/imu/data

#rtabmap with zed2i
ros2 launch rtabmap_launch rtabmap.launch.py \
   rtabmap_args:="--delete_db_on_start" \
   stereo:=true \
   left_image_topic:=/zed/zed_node/left_gray/image_rect_gray \
   right_image_topic:=/zed/zed_node/right_gray/image_rect_gray \
   left_camera_info_topic:=/zed/zed_node/left_gray/camera_info \
   right_camera_info_topic:=/zed/zed_node/right_gray/camera_info \
   frame_id:=zed_left_camera_frame \
   use_sim_time:=true \
   approx_sync:=true \
   qos:=2 \
   rviz:=false \
   queue_size:=100 \
   imu_topic:=/zed/zed_node/imu/data

Flight Tests with RTABMAP SLAM