Obstacle_Avoidance_ROS

Project in action : Watch on youtube

Cloning the project

Create a new directory in <catkin_workspace>/src/testbot_description and clone all of project files to that folder.

sample commands:

1. mkdir ~/catkin_ws/src/testbot_description
2. cd ~/catkin_ws/src/testbot_description
3. git clone https://github.com/vibhuthasak/Obstacle_Avoidance_ROS.git
4. cd ~/catkin_ws
5. catkin_make

Step by Step ROS Command Explanation

1. First you need to Launch the ROS node.

   roslaunch testbot_description testbot_gazebo.launch

   testbot_description is the package name that I gave. And testbot_gazebo.launch file can be found at /launch folder After executing this command, Gazebo will open like below.

Everthing looking great so far right ?

2. Now you need to run the python script that is created to listen sensor data from our virtual robot and move the robot.

   rosrun testbot_description sensor_data_listerner.py

Python Script Explanation in brief:

The python script is available at Obstacle_Avoidance_ROS/scripts/sensor_data_listener.py path.

The script is simply subcribes to /scan topic's sensor_msgs.msg.LaserScan message. The message is modified using the LaserScanProcess() function.

rospy.Subscriber("scan", sensor_msgs.msg.LaserScan , LaserScanProcess)

And it is publishing commands to /cmd_vel topic and the message type is Twist.

pub = rospy.Publisher('/cmd_vel', Twist, queue_size=10)

If you echo the /cmd_vel topic using following command

rostopic echo cmd_vel

You will see it is printing Linear and Angular velocities.

DONE