cheatsheet-ros-basic.md

ROS Cheatsheet

Workspace

Sourcing ROS

# Make sure you've added the system-wide ROS setup script to .bashrc file
# If you haven't done that, do it now, or source the file by hand

souce /opt/ros/kinetic/setup.bash

Creating a new workspace

STEP 1: Create a new workspace folder

# Create a new workspace folder, e.g. telebot_ws
mkdir -p /telebot_ws/src

STEP 2: Initialize the workspace

# Enter the src directory
cd telebot_ws/src

# Use catkin to initialize workspace
catkin_init_workspace

STEP 3: Generate the catkin workspace files

# Generate the catkin workspace files
cd ../telebot_ws
catkin_make

Packages

# Go into the workspace src directory
cd telebot_ws/src

# Create package e.g. my_awesome_code
catkin_create_pkg my_awesome_code rospy

Topics

Help on rostopic parameters

rostopic -h

List all topics

rostopic list

Show messages published to a topic

rostopic echo [topic-name] [param] [param-value]

# For example, for a node called 'counter'. Show only 5 messages
rostopic echo counter -n 5

Check publish rate

rostopic hz [topic-name]

# For example, for a node named 'counter'
rostopic hz counter

Display information about an advertised topic

rostopic info [topic-name]

# For example, for a node called 'counter'
rostopic info counter

Find topics of a given message type

rostopic find [message-type]

# For example, for a topic with 'std_msgs/Int32' type
rostopic find std_msgs/Int32

Publis a message to a topic

rostopic pub [topic_name] [message_type] [message_data]

# For example, for a topic named 'counter', publish a message with a type of 'std_msg/Int32' and a value 1000000
rostopic pub counter std_msgs/Int32 1000000