Book Image

Learning ROS for Robotics Programming

By : Aaron Martinez, Enrique Fernández
Book Image

Learning ROS for Robotics Programming

By: Aaron Martinez, Enrique Fernández

Overview of this book

<p>Both the amateur and the professional roboticist who has ever tried their hand at robotics programming will have faced with the cumbersome task of starting from scratch, usually reinventing the wheel. ROS comes with a great number of already working functionalities, and this book takes you from the first steps to the most elaborate designs possible within this software framework.</p> <p>"Learning ROS for Robotics Programming" is full of practical examples that will help you to understand the framework from the very beginning. Build your own robot applications in a simulated environment and share your knowledge with the large community supporting ROS.</p> <p>"Learning ROS for Robotics Programming" starts with the basic concepts and usage of ROS in a very straightforward and practical manner. It is a painless introduction to the fascinating world of robotics, covering sensor integration, modeling, simulation, computer vision, and navigation algorithms, among other topics.</p> <p>After the first two chapters, concepts like topics, messages, and nodes will become daily bread. Make your robot see with HD cameras, or navigate avoiding obstacles with range sensors. Furthermore, thanks to the contributions of the vast ROS community, your robot will be able to navigate autonomously, and even recognize and interact with you, in a matter of minutes.</p> <p>"Learning ROS for Robotics Programming" will give you all the background you need to know in order to start in the fascinating world of robotics and program your own robot. Simply, you put the limit!</p>
Table of Contents (16 chapters)
Learning ROS for Robotics Programming
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Debugging messages


It is good practice to include messages that indicate what the program is doing. However, we must do it without compromising the efficiency of our software and the clearance of its output. In ROS, we have an API that covers both features and is built on top of log4cxx (a port of the well-known log4j logger library). In brief, we have several levels of messages, which might have a name depending on a condition or even throttle, with a null footprint on the performance and full integration with other tools in the ROS framework. Also, they are integrated seamlessly with the concurrent execution of nodes, that is, the messages do not get split, but they can be interleaved according to their timestamps. In the following sections, we will explain the details and how to use them adequately.

Outputting a debug message

ROS comes with a great number of functions or macros that allow us to output a debugging message as well as errors, warnings, or simply informative messages. It offers...