The document discusses the Robot Operating System (ROS). It provides an introduction and overview of ROS including its design goals and nomenclature. It then describes several key use cases of ROS like debugging individual nodes, logging and playback capabilities, developing packaged subsystems, enabling collaborative development, providing visualization and monitoring tools, supporting composition of functionality through packages and stacks, and handling transformations between reference frames.

1. Morgan Quigley Presented By:-
Computer Science Department,
Stanford University. Ubaidullah Alias Kashif
Willow Garage, Menlo Park, CA MSCS-III
Computer Science Department, Sukkur IBA
University of Southern
California
1

2. Robot Operating System
 INTRODUCTION
 DESIGN GOALS
 NOMENCLATURE
 USE CASES

3. USE CASES
 Debugging a single node
 Logging and playback
 Packaged subsystems
 Collaborative Development
 Visualization and Monitoring
 Composition of functionality
 Transformations
 Conclusion

4. Debugging a single node
 A node is the well defined limited area of the system where
planning, reasoning, perception or control is performed.
 To get a robotic system up and running for experiments,
larger software ecosystem must exist.
 This adds a significant amount of difficulty to integrative
robotics research.
 ROS modular structure minimize the difficulty of
debugging in settings
 Nods connect to each other at run time
 The ease of inserting and removing nodes from a running
ROS based system is one of its most powerful and
fundamental features.

5. Logging and playback
 ROS supports generic logging and playback
functionality. Can be performed via command line and
requires no modification in source code.
 following network graph could be quickly set up to
collect a dataset for visual-odometry
research:
 To facilitate logging and monitoring , the rosconsole
library builds upon the Apache project’s
log4cxx system to provide a convenient
and elegant logging interface.

6. Packaged subsystems
 ROS leverages the algorithms implemented in the
Player project to provide a navigation system,
producing this graph:
 To allow for “packaged” functionality
such as a navigation system,
ROS provides a tool called roslaunch,
which reads an XML description
of a graph and instantiates the graph
on the cluster.

7. Collaborative Development
 To support collaborative development,
 the ROS software system is organized into packages.
 A ROS package is simply a directory which contains an
XML file describing the package and stating any
dependencies.
 For example, one ROS repository has root directories
including “nav,” “vision,” and “motion planning,” each of
which contains many packages as subdirectories.
 ROS provides a utility called rospack to query and inspect
the code tree, search dependencies, find packages by name,
etc

8. Visualization and Monitoring
 While designing and debugging robotics software, it often
becomes necessary to observe some state while the system is
running.
 Printf technique can be difficult to extend to large-scale
distributed systems, and can become unwieldy for general-
purpose monitoring.
 Instead, ROS can exploit the dynamic nature of the connectivity
graph to “tap into” any message stream on the system.
 rviz program, which is distributed with ROS. Visualization
panels can be dynamically instantiated to view a large variety of
data types, point clouds, geometric primitives (such as object
 recognition results), render robot poses and trajectories, etc.

9. Composition of functionality
 In ROS, a “stack” of software is a cluster of nodes that
does something useful.
 The previous graph was automatically generated by the
rxgraph tool, which can inspect and monitor any
ROS graph at runtime. Its output renders nodes as
ovals, topics as squares, and connectivity as arcs.

10. Hierarchical multi-robot control system constructed by simply instantiating
multiple navigation stacks, each in their own namespace:

11. Transformations
 Robotic systems often need to track spatial
relationships for a variety of reasons: between a mobile
robot and some fixed frame of reference for
localization.
 The tf system constructs a dynamic transformation
tree which relates all frames of reference in the system.
 For example, the tf system can be used to easily
generate point clouds in a stationary “map” frame from
laser scans received by a tilting laser scanner on a
moving robot

12.  ROS robot software distributions
 ROS Fuerte (April, 2012)
 ROS Electric (August, 2011)
 ROS Diamondback (March, 2011)
 ROS C Turtle (August, 2010)
 ROS Box Turtle (March, 2010)

13.  Robots Using ROS (Ongoing Series)
 From small differential-drive robots to mobile manipulators to
autonomous cars, robots of every size and shape are using ROS
to do interesting research and applications development. Groups
around the world are also releasing free, open-source software to
get you started on your own robot.
 Part 6: Helicopters Using ROS
 Part 5: Meka, Qbo, Mini-PR2, Lego NXT
 Part 4: Shadow Dextrous Hand, Robotino, Penn Quadrotors,
Washington University's B21r and Videre ERRATICs
 Part 3: TUM-Rosie, Marvin, HERB, CKBots
 Part 2: Care-O-bot 3, BOSCH RTC, EL-E and Cody, Kawada
HRP2-V
 Part 1: STAIR 1, Aldebaran Nao, Junior
 App Sprints

14. THANKS
 http://www.ros.org
 http://www.willowgarage.com/pages/software/ros-platform
 http://www.ros.org/wiki/rviz
 https://www.developers.google.com/chart/image/docs/gallery/graphviz
 http://answers.ros.org/question/35884/rviz-camera-display-camera_info-
problem/