Update ros.rst

dev/source/docs/ros.rst

@@ -9,7 +9,7 @@ ROS
 
 ArduPilot capabilities can be extended with `ROS <http://www.ros.org/>`__ (aka Robot Operating System).
 
-`ROS <http://www.ros.org/>`__ provides libraries, tools, hardware abstraction, device drivers, visualizers, message-passing, package management, and more to help software developers create robot applications.  In the future we expect ROS will be replaced by `ROS2 <http://design.ros2.org/articles/why_ros2.html>`__
+`ROS <http://www.ros.org/>`__ provides libraries, tools, hardware abstraction, device drivers, visualizers, message-passing, package management, and more to help software developers create robot applications.  In the future, we expect ROS will be replaced by `ROS2 <http://design.ros2.org/articles/why_ros2.html>`__
 
 `MAVROS <http://wiki.ros.org/mavros>`__ is a ROS "node" that can convert between ROS topics and `MAVLink messages <https://github.com/ArduPilot/mavlink>`__ allowing ArduPilot vehicles to communicate with ROS.  The `MAVROS code can be found here <https://github.com/mavlink/mavros/tree/master/mavros>`__.
 
@@ -36,9 +36,9 @@ These pages will show you how to:
 Prerequisites
 =============
 
-- Learn on to use ArduPilot first by following the relevant wiki for `Rover <https://ardupilot.org/rover/index.html>`__, `Copter <https://ardupilot.org/copter/index.html>`__ or `Plane <https://ardupilot.org/plane/index.html>`__. In particular make sure the vehicle works well in Manual and Autonomous modes like Guided and Auto before trying to use ROS.
+- Learn on to use ArduPilot first by following the relevant wiki for `Rover <https://ardupilot.org/rover/index.html>`__, `Copter <https://ardupilot.org/copter/index.html>`__ or `Plane <https://ardupilot.org/plane/index.html>`__. In particular, make sure the vehicle works well in Manual and Autonomous modes like Guided and Auto before trying to use ROS.
 - Learn how to use ROS by reading the `beginner tutorials <http://wiki.ros.org/ROS/Tutorials>`__.  In the case of a problem with ROS, it is best to ask on ROS community forums first (or google your error). You will find many other tutorials about ROS like `Emlid <https://docs.emlid.com/navio2/common/dev/ros/>`__.
-- Install ROS Kinetic Kame on Ubuntu Linux (16.04). Those are default and LTS version of both ROS and Ubuntu.  ROS does not yet officially support Windows nor MAC.
+- Install ROS Kinetic Kame on Ubuntu Linux (16.04). Those are the default and LTS versions of both ROS and Ubuntu.  ROS does not yet officially support Windows nor MAC.
 
     VR Robotics has successfully used Rover with ROS for SLAM as demonstrated below.