Material for the ros2 crash course

Overview

ROS2 Crash course

Task 1 Create your new workspace

mkdir -p /home/usr/ros2/workspaces/ros2_crash_ws/src
cd /home/usr/ros2/workspaces/ros2_crash_ws/src

Task 2 Get teleop ros package and modify it

1) Clone the ros package repo
	cd /home/usr/ros2/workspaces/ros2_crash_ws/src/
	git clone [email protected]:ros2/teleop_twist_keyboard.git
	source /opt/ros/foxy/setup.bash
2) Compile the workspace
	cd /home/usr/ros2/workspaces/ros2_crash_ws/
	colcon build
3) Run the binary teleop_twist_keyboard.py and play with it! 
	ros2 run teleop_twist_keyboard teleop_twist_keyboard

Q1: How can we test our program? Hint: ros topics!

4) Add a customized print message in the file teleop_twist_keyboard.py and run it again

Q2: What happened? Hint: underlay vs overlay

5) Modify the binary teleop_twist_keyboard.py to generate the following motions:

	Linear motions: 

	u: left-front
	i: front
	o: right-front
	j: left
	k: stop
	l: right
	m: left-back
	,: back
	.: right-back

	Angular Motions:
	w: counter-clockwise
	e: stop
	r: clock-wise

	Speed:

	+ increase linear speed +0.1
	- decrease linear speed -0.1
	* increase angular speed +0.1
	/ decrease angular speed -0.1

6) Test your new binary
	Open a new terminal and source your workspace
	cd /home/usr/ros2/workspaces/ros2_crash_ws/
	source install/setup.bash
	ros2 run teleop_twist_keyboard teleop_twist_keyboard --ros-args --remap /cmd_vel:=turtle_twist

Q3: Does it work?

Task 3 Create a new ros2 cpp package named "turtle_msg"

1) Use the ros2 create package function 
	cd /home/usr/ros2/workspaces/ros2_crash_ws/src
	ros2 pkg create --build-type ament_cmake turtle_msgs
2) Compile the workspace
	colcon build --symlink-install --merge-install --cmake-args -DCMAKE_EXPORT_COMPILE_COMMANDS=1

Q4: Any problems? Do you notice any difference with the additional compiling arguments?

3) Add msg/TurtleState.msg and modify CMakeLists.txt, package.xml
4) Compile your workspace
5) Verify that your new message has been created, using ros2 interface.

Q5: Can you find your new message? Hint: overlay

Task 4 Create a new ros2 cpp package "turtle_ctrl"

1) Use the ros2 create package function 
	cd /home/dean/ros2/workspaces/ros2_crash_ws/src
	ros2 pkg create --build-type ament_cmake turtle_ctrl
2) Compile your workspace
3) Copy the TurtleVis class files TurtleVis.h and TurtleVis.cpp to their corresponding folders
4) Modify the CMakeFile to create a shared library with the TurtleVis class
5) Copy the application file turtle_vis.cpp
6) Modify the CMakeFile to create a new binary (Exec)
7) Compile your workspace (or single ros package)
8) Copy the file "turtle.rviz" into turtle_ctr/rviz/turtle.rviz
9) Test your application. You will need 3 terminals
	T1) Run the turtle visualization 
		ros2 run turtle_ctrl turtle_vis
	T2) Run rviz
		ros2 run rviz2 rviz2 -d src/turtle_ctrl/rviz/turtle.rvi
	T3) Publish a TurtleState message and check the rviz window
		ros2 topic pub --rate 1 /turtle_pose turtle_msgs/msg/TurtleStateStamped "{pose: {x: 1, y: 1, theta: 0}}"

Q6: What can you see?

Task 5 Let's create a lunch file to automate the above process

1) Copy the file "turtle_vis_test_launch.py" into the folder turtle_ctrl/launch/
2) Run the new launch file
	ros2 launch turtle_ctrl turtle_vis_test_launch.py

Q7: Does it work? What happened?

Task 6 Create the controller

1) Copy the class files  TurtleCtrl.cpp and TurtleCtrl.h to its corresponding folders
2) Modify the CMakeFile to create a shared library with the control class
3) Copy the application file turtle_control.cpp
4) Modify the CMakeFile to create a new binary (Exec)
5) Compile your workspace (or single ros package) 
6) Test your application
	T1) Copy the launch file turtle_vis_test_launch.py and renamed as turtle_test_launch.py
		Modify the new launch file to include the control node

Q8: How can you test your application?

Task 7 Trajectory generator

We will implement two methods to generate the commanded turtle pose for the controller.
First, transform the Twist (turtle velocity) message generated from the node teleop_twist_keyboard to continuous 
commanded turtle poses. 
Second, we will create a node that provides a service to request a desired turtle pose. This node will use the
requested turtle pose and generate a continuous smooth trajectory for the commanded turtle pose. 
The output of both nodes is a TurtleStateStamped message, which is connected to the controller to change the 
pose of the turtle
1) Create a new ros python package "turtle_trajectory_generator"
	ros2 pkg create --build-type ament_python turtle_trajectory_generator
2) Fix the ros package configuration files to use the new package, e.g. package.xml, resource, setup.py, etc.
3) Copy the file teleop_twist_keyboard.py from the ros package teleop_twist_keyboard to this new package
4) Compile the workspace. This is needed to create the symbolic links to the python files. 
	colcon build --symlink-install --merge-install --cmake-args -DCMAKE_EXPORT_COMPILE_COMMANDS=1
5) Create the trajectory generator module. Use the file trajectory_generator_class.py 
6) Compile again the workspace
7) Create the application nodes
	a) applications/poly_trajectories.py: Generates the smooth trajectory for the commanded turtle pose (TurtleStateStamped message)
	b) applications/twist2cmd.py: Converts from Twist message to commanded turtle pose (TurtleStateStamped message)
8) Compile your workspace 
7) Test your applications

Q9: How can you test the trajectory generator nodes only? Hint: ros2 run rqt_plot rqt_plot Q9: Does it work? Hint: did you configure your setup.py file?

Running Demo

Turtle Ctrl + Vis

T1) cd /home/dean/ros2/workspaces/ros2_crash_ws/

source install/setup.bash

ros2 launch turtle_ctrl turtle_test_launch.py

T2) ros2 topic pub --rate 1 /turtle_pose turtle_msgs/msg/TurtleStateStamped "{pose: {x: 0, y: 1, theta: 0}}"

Turtle Trajectory + Ctrl + Vis

ros2 launch turtle_ctrl turtle_test_launch.py

Keyboard commands (Velocity reference)

T1) ros2 run turtle_trajectory_generator twist2cmd

T2) ros2 run turtle_trajectory_generator teleop_twist_keyboard --ros-args --remap /cmd_vel:=turtle_twist

Spline (Smooth Position Commands)

T1) ros2 run turtle_trajectory_generator poly_trajectory

T2) ros2 service call /set_desired_pose turtle_msgs/srv/SetDesiredPose "{ turtle_d:{x: 1, y: 0, theta: 0}, time: 1}"

Owner
Emmanuel Dean
Emmanuel Dean
Python For Finance Cookbook - Code Repository

Python For Finance Cookbook - Code Repository

Packt 544 Dec 25, 2022
Main repository for the Sphinx documentation builder

Sphinx Sphinx is a tool that makes it easy to create intelligent and beautiful documentation for Python projects (or other documents consisting of mul

5.1k Jan 04, 2023
204-python-string-21BCA90 created by GitHub Classroom

204-Python This repository is created for subject "204 Programming Skill" Python Programming. This Repository contain list of programs of python progr

VIDYABHARTI TRUST COLLEGE OF BCA 6 Mar 31, 2022
A tutorial for people to run synthetic data replica's from source healthcare datasets

Synthetic-Data-Replica-for-Healthcare Description What is this? A tailored hands-on tutorial showing how to use Python to create synthetic data replic

11 Mar 22, 2022
Docov - Light-weight, recursive docstring coverage analysis for python modules

docov Light-weight, recursive docstring coverage analysis for python modules. Ov

Richard D. Paul 3 Feb 04, 2022
Obmovies - A short guide on setting up the system and environment dependencies required for ob's Movies database

Obmovies - A short guide on setting up the system and environment dependencies required for ob's Movies database

1 Jan 04, 2022
Fully typesafe, Rust-like Result and Option types for Python

safetywrap Fully typesafe, Rust-inspired wrapper types for Python values Summary This library provides two main wrappers: Result and Option. These typ

Matthew Planchard 32 Dec 25, 2022
A Collection of Cheatsheets, Books, Questions, and Portfolio For DS/ML Interview Prep

Here are the sections: Data Science Cheatsheets Data Science EBooks Data Science Question Bank Data Science Case Studies Data Science Portfolio Data J

James Le 2.5k Jan 02, 2023
Sphinx Theme Builder

Sphinx Theme Builder Streamline the Sphinx theme development workflow, by building upon existing standardised tools. and provide a: simplified packagi

Pradyun Gedam 23 Dec 26, 2022
Hjson for Python

hjson-py Hjson, a user interface for JSON Hjson works with Python 2.5+ and Python 3.3+ The Python implementation of Hjson is based on simplejson. For

Hjson 185 Dec 13, 2022
AiiDA plugin for the HyperQueue metascheduler.

aiida-hyperqueue WARNING: This plugin is still in heavy development. Expect bugs to pop up and the API to change. AiiDA plugin for the HyperQueue meta

AiiDA team 3 Jun 19, 2022
Explain yourself! Interrogate a codebase for docstring coverage.

interrogate: explain yourself Interrogate a codebase for docstring coverage. Why Do I Need This? interrogate checks your code base for missing docstri

Lynn Root 435 Dec 29, 2022
Quickly download, clean up, and install public datasets into a database management system

Finding data is one thing. Getting it ready for analysis is another. Acquiring, cleaning, standardizing and importing publicly available data is time

Weecology 274 Jan 04, 2023
Automatic links from code examples to reference documentation

sphinx-codeautolink Automatic links from Python code examples to reference documentation at the flick of a switch! sphinx-codeautolink analyses the co

Felix Hildén 41 Dec 17, 2022
A Python library for setting up projects using tabular data.

A Python library for setting up projects using tabular data. It can create project folders, standardize delimiters, and convert files to CSV from either individual files or a directory.

0 Dec 13, 2022
Data science Python notebooks: Deep learning (TensorFlow, Theano, Caffe, Keras), scikit-learn, Kaggle, big data (Spark, Hadoop MapReduce, HDFS), matplotlib, pandas, NumPy, SciPy, Python essentials, AWS, and various command lines.

Data science Python notebooks: Deep learning (TensorFlow, Theano, Caffe, Keras), scikit-learn, Kaggle, big data (Spark, Hadoop MapReduce, HDFS), matplotlib, pandas, NumPy, SciPy, Python essentials, A

Donne Martin 24.5k Jan 09, 2023
Plotting and analysis tools for ARTIS simulations

Artistools Artistools is collection of plotting, analysis, and file format conversion tools for the ARTIS radiative transfer code. Installation First

ARTIS Monte Carlo Radiative Transfer 8 Nov 07, 2022
Generate YARA rules for OOXML documents using ZIP local header metadata.

apooxml Generate YARA rules for OOXML documents using ZIP local header metadata. To learn more about this tool and the methodology behind it, check ou

MANDIANT 34 Jan 26, 2022
ReStructuredText and Sphinx bridge to Doxygen

Breathe Packagers: PGP signing key changes for Breathe = v4.23.0. https://github.com/michaeljones/breathe/issues/591 This is an extension to reStruct

Michael Jones 643 Dec 31, 2022
Loudchecker - Python script to check files for earrape

loudchecker python script to check files for earrape automatically installs depe

1 Jan 22, 2022