Setup & Installation 🤖

Overview

This section explains how to build, launch, and verify the complete software stack of Pixel Robot.
Robot bringup refers to starting all essential components required for the robot to operate correctly, including sensors, motor control, state publishing, and visualization.

Prerequisites

Before proceeding, ensure that:

  • Ubuntu 22.04 is installed
  • ROS 2 Humble is installed and sourced
  • The robot hardware is fully assembled
  • Battery is charged and power system is functional
  • ESP32 firmware is already flashed
  • All sensors are properly connected

Update system packages and install essential tools

sudo apt update && sudo apt upgrade -y
sudo apt install -y curl wget htop net-tools openssh-server rsync tmux python3 python3-pip python3-rosdep gazebo git python3-colcon-common-extensions terminator
sudo apt install ros-humble-rviz2 ros-humble-slam-toolbox ros-humble-turtlebot3-gazebo ros-humble-joint-state-publisher-gui ros-humble-gazebo-ros-pkgs

One time setup

echo 'export TURTLEBOT3_MODEL=burger' >> ~/.bashrc
echo 'source /usr/share/gazebo/setup.sh' >> ~/.bashrc
echo 'export GAZEBO_MODEL_PATH=~/titan_ws/src/titan_simulation/turtlebot3_gazebo/models:$GAZEBO_MODEL_PATH' >> ~/.bashrc
echo 'source ~/titan_ws/install/setup.bash' >> ~/.bashrc

Workspace Setup

Create and initialize a ROS 2 workspace:

mkdir -p ~/titan_ws
cd ~/titan_ws

Clone the Pixel Robot repository:

git clone https://github.com/MRS111-OS/titan_robot.git
mv titan_robot/ src

Install dependencies

sudo rosdep init
rosdep update
rosdep install --from-paths src --ignore-src -y

Build the workspace:

cd ~/titan_ws
colcon build --symlink-install --parallel-workers 4

Source the workspace:

source install/setup.bash

It is recommended to add the source command to your .bashrc for convenience.

Bringup Launch Description

Pixel Robot uses a single bringup launch file that initializes all core components.

The bringup launch typically starts:

  • Robot description (URDF)
  • State publisher
  • LIDAR driver
  • ESP32 serial communication node
  • Static and dynamic TFs

Launching the Robot

Power on the robot and run the bringup launch file:

ros2 launch titan_bringup titan_bringup.launch.py

Once launched, the following should occur:

  • LIDAR begins publishing scan data
  • ESP32 establishes serial communication
  • Odometry is published to /odom
  • TF tree is available
  • RViz2 opens with a preconfigured view

Verifying Bringup

After launching, verify that all core components are running correctly.

Check Active Topics

ros2 topic list

You should see topics such as:

  • /scan
  • /odom
  • /cmd_vel
  • /tf
  • /tf_static

Verify Odometry

ros2 topic echo /odom
  • Values should update when the robot moves
  • Position and orientation should change smoothly

Verify LIDAR Data

ros2 topic echo /scan

Or visualize directly in RViz2.

Verify TF Tree

ros2 run tf2_tools view_frames

Confirm that frames such as odom, base_link, and laser are present.

Common Bringup Issues

Issue Possible Cause
No odometry ESP32 not connected or firmware not running
No LIDAR data USB connection or driver issue
Robot not moving Motor power or serial issue
RViz not showing data Incorrect fixed frame or TF missing

Keyboard Teleoperation

Keyboard teleoperation is useful for testing hardware, mapping environments, and manual control.

Run Keyboard Teleop

Open a new terminal and source the workspace:

source ~/titan_ws/install/setup.bash

Run the teleop node:

ros2 run teleop_twist_keyboard teleop_twist_keyboard

Teleop Controls

i Forward
k Stop
j Rotate Left
l Rotate Right
, Backward

q/z Increase/Decrease Linear Speed
w/x Increase/Decrease Angular Speed

Velocity commands are published to the /cmd_vel topic and sent to the ESP32.

Safety Notes

  • Always keep the robot in an open area during teleoperation
  • Start with low velocity limits
  • Be ready to stop the robot immediately
  • Do not lift the robot while motors are powered

Your robot is now up and running 🚀