Lab 5

###Getting Started To launch up Gazebo with an ArDrone and a landing pad., execute

roslaunch intro_to_robotics landing_pad.launch

Take a look at the file [nodes/ardrone_example.py] (https://github.com/IRLL/IntroToRobotics/blob/master/nodes/ardrone_example.py). You can use this code as a starting point.

###ArDrone Cameras The ArDrone has two cameras, a forward-facing one and a downward-facing one. You will be using the bottom camera for this lab. Unfortunately, you can only view one camera at a time with the ArDrone. To switch the active camera, run

rosservice call /ardrone/togglecam

in a terminal. The bottom camera's resolution is 640x360.

###Controlling the ArDrone The ArDrone is controlled via a Twist message sent to the /cmd_vel topic, similar to the turtlebot. The following actions are available:

• twist.linear.x - to move forwards/backwards
• twist.linear.y – to strafe
• twist.linear.z – to move up/down
• twist.angular.z – to rotate

###ArDrone Sensors If you're interested, there are a bunch of other topics the ArDrone publishes such as battery info, elevation, current status. You can take a look at the [official documentation] (http://ardrone-autonomy.readthedocs.org/en/latest/reading.html). However, some of the topics are slightly different between the simulated ArDrone and the real one, so the documentation may not be completely correct.