updated readme: auto hover

README.md

@@ -6,6 +6,7 @@
 
 ### Updates
 
+- *January XX 2013*: 
 - *November 9 2012*: Critical Bug in sending configurations to drone fixed and more parameters are supported ([More info](https://github.com/AutonomyLab/ardrone_autonomy/issues/24)). Seperate topic for magnetometer data added ([More info](https://github.com/AutonomyLab/ardrone_autonomy/pull/25)).
 - *September 5 2012*: Experimental automatic IMU bias removal.
 - *August 27 2012*: Thread-safe SDK data access. Synchronized `navdata` and `camera` topics.
@@ -19,7 +20,7 @@
 
 ### Pre-requirements
 
-This driver has been tested on Linux machines running Ubuntu 11.10 & 12.04 (32 bit and 64 bit). However it should also work on any other mainstream Linux distribution. The driver has been tested on both ROS "electric" and "fuerte". The AR-Drone SDK has its own build system which usually handles system wide dependencies itself. The ROS package depends on these standard ROS packages: `roscpp`, `image_transport`, `sensor_msgs`, `tf`, `camera_info_manager` and `std_srvs`.
+This driver has been tested on Linux machines running Ubuntu 11.10, 12.04 & 12.10 (32 bit and 64 bit). However it should also work on any other mainstream Linux distribution. The driver has been tested on both ROS "electric" and "fuerte". The AR-Drone SDK has its own build system which usually handles system wide dependencies itself. The ROS package depends on these standard ROS packages: `roscpp`, `image_transport`, `sensor_msgs`, `tf`, `camera_info_manager` and `std_srvs`.
 
 ### Installation Steps
 
@@ -143,7 +144,11 @@ In order to fly the drone after takeoff, you can publish a message of type [`geo
         -angular.z: turn left
         +angular.z: turn right
 
-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. Publishing "0" values for all components will make the drone keep hovering.
+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 variable called `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.
 
 ## Coordinate Frames