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You're reading from Effective Robotics Programming with ROS Find out everything you need to know to build powerful robots with the most up-to-date ROS

Product type Paperback

Published in Dec 2016

Publisher Packt

ISBN-13 9781786463654

Length 468 pages

Edition 3rd Edition

Tools

ROS

Concepts

Robotics

Authors (3):

Luis S√°nchez

Enrique Fernandez Perdomo

Anil Mahtani

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Table of Contents (12) Chapters

Preface

1. Getting Started with ROS FREE CHAPTER

2. ROS Architecture and Concepts

3. Visualization and Debugging Tools

4. 3D Modeling and Simulation

5. The Navigation Stack – Robot Setups

6. The Navigation Stack – Beyond Setups

7. Manipulation with MoveIt!

8. Using Sensors and Actuators with ROS

9. Computer Vision

10. Point Clouds

Index

Camera calibration

Most cameras, especially wide-angle ones, exhibit large distortions. We can model such distortions as radial or tangential and compute the coefficients of that model using calibration algorithms. The camera calibration algorithms also obtain a calibration matrix that contains the focal distance and principle point of the lens and, hence, provide a way to measure distances in the world using the images acquired. In the case of stereo vision, it is also possible to retrieve depth information, that is, the distance of the pixels to the camera, as we will see later. Consequently, we have 3D information of the world up to a certain extent.

The calibration is done by showing several views of a known image called a calibration pattern, which is typically a chessboard/checkerboard. It can also be an array of circles or an asymmetric pattern of circles; note that circles are seen as ellipses by the camera for skew views. A detection algorithm obtains the inner corner point of the...

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Authors (3)

Mahtani

Anil Mahtani is a computer scientist who has dedicated an important part of his career to underwater robotics. He first started working in the field with his master thesis, where he developed a software architecture for a low-cost ROV. During the development of his thesis, he also became the team leader and lead developer of AVORA, a team of university students that designed and developed an autonomous underwater vehicle for the Students Autonomous Underwater Challenge Europe (SAUC-E) in 2012. That same year, Anil Mahtani completed his thesis and his MSc in Computer Science at the University of Las Palmas de Gran Canaria and then became a Software Engineer at SeeByte Ltd, a world leader in smart software solutions for underwater systems. In 2015, he joined Dell Secureworks as a Software Engineer, where he applies his knowledge and skills toward developing intrusion detection and prevention systems. During his time at SeeByte Ltd, Anil Mahtani played a key role in the development of several semi-autonomous and autonomous underwater systems for the military and oil and gas industries. In those projects, he was heavily involved in the development of autonomy systems, the design of distributed software architectures, and low-level software development and also contributed in providing Computer Vision solutions for front-looking sonar imagery. At SeeByte Ltd, he also achieved the position of project manager, managing a team of engineers developing and maintaining the internal core C++ libraries. His professional interests lie mainly in software engineering, algorithms, data structures, distributed systems, networks, and operating systems. Anil's main role in robotics is to provide efficient and robust software solutions, addressing not only the current problems at hand but also foreseeing future problems or possible enhancements. Given his experience, he is also an asset when dealing with Computer Vision, machine learning, or control problems. Anil has also interests in DIY and electronics, and he has developed several Arduino libraries, which he has contributed back to the community.

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Fernandez Perdomo

Enrique Fernandez Perdomo has a PhD in Computer Engineer from the ULPGC. In his PhD thesis, he investigated path planning algorithms for Autonomous Underwater Gliders, and did an internship at the CIRS/VICOROB research group at the University of Girona. He also worked with ground robots and is currently a senior Robotics Engineer in the Autonomy Team at Clearpath Robotics since 2015. He was a member of the navigation department at PAL Robotics since 2013. He has good programming skills in C++ and Python, and develops wheeled controllers, a tele-operation infrastructure for both the wheeled and biped robots (REEM and REEM-C), SLAM algorithms, laser and visual localization, and autonomous navigation based on the ROS navigation stack. Finally, he worked on the project that develop a low-cost mobile base for high payload and retail applications, which is used on the TiaGo robot. Now at Clearpath Robotics, he works on SLAM and localization algorithms and has participated in the OTTO project.

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Sánchez

Luis Snchez has completed his dual master's degree in electronics and telecommunication engineering at the University of Las Palmas de Gran Canaria. He has collaborated with different research groups as the Institute for Technological Development and Innovation (IDETIC), the Oceanic Platform of Canary Islands (PLOCAN), and the Institute of Applied Microelectronics (IUMA) where he actually researches on imaging super-resolution algorithms. His professional interests lie in Computer Vision, signal processing, and electronic design applied on robotics systems. For this reason, he joined the AVORA team, a group of young engineers and students working on the development of Underwater Autonomous Vehicles (AUV) from scratch. Inside this project, Luis has started developing acoustic and Computer Vision systems, extracting information from different sensors such as hydrophones, sonar, or camera. With a strong background gained in marine technology, Luis cofounded Subsea Mechatronics, a young start-up, where he works on developing remotely operated and autonomous vehicles for underwater environments. Here's what Dario Sosa Cabrera, a marine technologies engineer and entrepreneur (and the cofounder and maker of LPA Fabrika: Gran Canaria Maker Space) has to say about Luis: "He is very enthusiastic and an engineer in multiple disciplines. He is responsible for his work. He can manage himself and can take up responsibilities as a team leader, as demonstrated at the euRathlon competition. His background in electronics and telecommunications allows him to cover a wide range of expertise from signal processing and software, to electronic design and fabrication." Luis has participated as a technical reviewer of the previous version of Learning ROS for Robotics Programming and as a cowriter of the second edition.

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You're reading from Effective Robotics Programming with ROS Find out everything you need to know to build powerful robots with the most up-to-date ROS

Table of Contents (12) Chapters

Camera calibration

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Authors (3)

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