Book Image

ROS Robotics Projects - Second Edition

By : Ramkumar Gandhinathan
Book Image

ROS Robotics Projects - Second Edition

By: Ramkumar Gandhinathan

Overview of this book

Nowadays, heavy industrial robots placed in workcells are being replaced by new age robots called cobots, which don't need workcells. They are used in manufacturing, retail, banks, energy, and healthcare, among other domains. One of the major reasons for this rapid growth in the robotics market is the introduction of an open source robotics framework called the Robot Operating System (ROS). This book covers projects in the latest ROS distribution, ROS Melodic Morenia with Ubuntu Bionic (18.04). Starting with the fundamentals, this updated edition of ROS Robotics Projects introduces you to ROS-2 and helps you understand how it is different from ROS-1. You'll be able to model and build an industrial mobile manipulator in ROS and simulate it in Gazebo 9. You'll then gain insights into handling complex robot applications using state machines and working with multiple robots at a time. This ROS book also introduces you to new and popular hardware such as Nvidia's Jetson Nano, Asus Tinker Board, and Beaglebone Black, and allows you to explore interfacing with ROS. You'll learn as you build interesting ROS projects such as self-driving cars, making use of deep learning, reinforcement learning, and other key AI concepts. By the end of the book, you'll have gained the confidence to build interesting and intricate projects with ROS.
Table of Contents (14 chapters)

ROS tools

ROS has a variety of GUI and command-line tools to inspect and debug messages. These tools come in handy when you're working in a complex project involving a lot of package integrations. It would help to identify whether the topics and messages are published in the right format and are available to the user as desired. Let's look at some commonly used ones.

ROS Visualizer (RViz)

RViz (http://wiki.ros.org/rviz) is one of the 3D visualizers available in ROS that can visualize 2D and 3D values from ROS topics and parameters. RViz helps to visualize data such as robot models, robot 3D transform data (TF), point cloud, laser and image data, and a variety of different sensor data:

Point cloud data visualized in RViz

The preceding screenshot shows a 3D point cloud scan from a Velodyne sensor placed on an autonomous car.

rqt_plot

The rqt_plot program (http://wiki.ros.org/rqt_plot) is a tool for plotting scalar values that are in the form of ROS topics. We can provide a topic name in the Topic box:

rqt_plot

The preceding screenshot is a plot of a pose from the turtle_sim node.

rqt_graph

The rqt_graph (http://wiki.ros.org/rqt_graph) ROS GUI tool can visualize the graph of interconnection between ROS nodes:

rqt_graph

The complete list of ROS tools is available at the following link: http://wiki.ros.org/Tools.

Since we now have a brief idea of the ROS tools, we can cover different ROS simulators.