Expanding README.

README.md

@@ -1,26 +1,30 @@
-# README #
+# Introduction
 
-### ROS_KVH1750 ###
+This ROS package provides an interface to interface with the [KVH 1750 IMU](http://www.kvh.com/Military-and-Government/Gyros-and-Inertial-Systems-and-Compasses/Gyros-and-IMUs-and-INS/IMUs/1750-IMU.aspx), with support for a hardware time-of-validity signal using serial, and a plugin interface for supporting alternate publishing schemes. These are used to support the message types for MIT's [Pronto](https://github.com/ipab-slmc/pronto-distro) state estimation library.
 
-* Provides ROS Support for the KVH 1750 IMU
-* Developed out of the Terrestrial Robotics Engineering & Controls Lab at Virginia Tech
+# Configuration
 
-### How do I get set up? ###
+1. `link_name` - link IMU is associated with
+2. `processor_type` - string representing name of a [pluginlib](http://wiki.ros.org/pluginlib) plugin to load for processing processing IMU data. This should be based on the MessageProcessorBase class in the repository.
+3. `rate` - Frequency to set the IMU reporting data.
+4. `use_delta_angles` - sets whether the IMU reports delta angles (change in angles between readings) or angular rates.
+5. `priority` - Priority for this node to be inserted into the scheduler.
+6. `use_rt` - Flag to indicate if the node should be inserted into the round-robin scheduler.
+7. `orientation_covariance` - Array of orientation covariances inserted into each IMU message.
+8. `angular_covariance` - Array of angular covariances inserted into each IMU message.
+9. `linear_covariance` - Array of linear covariances inserted into each IMU message.
+10. `address` - The file to open for reading the IMU.
+11. `tov_address` - File to open for reading the time-of-validity signal. This uses the [serial](http://wiki.ros.org/serial) library to perform the reading.
+12. `baudrate` - Baud rate at which to read the IMU. *NOTE:* This must match the setting on the IMU, or else communication cannot be established.
+13. `max_temp` - temperature at which to stop reading the IMU, as a safety feature.
 
-* Summary of set up
-* Configuration
-* Dependencies
-* Database configuration
-* How to run tests
-* Deployment instructions
+# Time of Validity
 
-### Contribution guidelines ###
+In order to receive time-of-validity, this package requires that a serial message is sent on the `tov_address` file descriptor. The contents of the message is irrelevant - an empty message is preferred for accuracy and reducing system latency.
 
-* Writing tests
-* Code review
-* Other guidelines
+# Contributing
 
-### Who do I talk to? ###
-
-* Repo owner or admin
-* Other community or team contact
+1. Fork this repository, make suggested changes.
+2. If the change is minor (e.g. can be read and understood in a short period of time, does not require much discussion) issue a pull request.
+3. If the change is more significant or requires discussion, open an issue explaining the issue and current thoughts. Open a pull request demonstrating a proposed solution, if one exists.
+4. Pull requests should be reviewed by a maintainer, and handled as appropriate.