Sending Commands to AR-Drone

The drone will takeoff, land or emergency stop/reset if a ROS std_msgs/Empty message is published to ardrone/takeoff, ardrone/land and ardrone/reset topics respectively.

In order to fly the drone after takeoff, you can publish a message of type geometry_msgs::Twist to the cmd_vel topic:

-linear.x: move backward
+linear.x: move forward
-linear.y: move right
+linear.y: move left
-linear.z: move down
+linear.z: move up

-angular.z: turn right
+angular.z: turn left

The range for each component should be between -1.0 and 1.0. The maximum range can be configured using ROS Parameters_ discussed later in this document.

Hover Modes

geometry_msgs::Twist has two other member variables angular.x and angular.y which can be used to enable/disable “auto-hover” mode. “auto-hover” is enabled when all six components are set to zero. If you want the drone not to enter “auto hover” mode in cases you set the first four components to zero, set angular.x and angular.y to arbitrary non-zero values.