Updated README

README.md

@@ -1,10 +1,21 @@
-# omni-platform control system
-This project aims to develop control system for omnidirectional wheeled platform. 
+# Introduction
+This repository is part of [OmniCar project](https://divelix.github.io/OmniCar/) and represents program for Arduino MEGA that solves omni platform kinematics to get wheel odometry solution and reach desired velocity.
 
-(c) ITMO University and contributors
-GNU GENERAL PUBLIC LICENSE
+# Showcase
+Arduino MEGA runs code of this repository and placed on the 1st floor of the mobile platform. It has `Freeduino Motor Shield V3` and special power board (reduces wiring) mounted on top of it.
 
-# Introduction
-The code in this repository is intended to control mobile platform that consists of:
-* 4 DC motors with encoders (JGB37-520) + mecanum wheels
-* Arduino MEGA 2560
+The platform has 4 mecanum wheels based on JGB37-520 DC motors with incremental encoders. Each encoder uses 2 interrupt pins.
+Chosen configuration has only 4 free interrupt pins (other ones are used or unreachable because of motor shield): 18, 19, 20, 21 - they are used by 2 front wheels. Two rear wheels use "fake" interrupts via `PinChangeInterrupt` library: 50, 51, 52, 53.
+![First floor of the platform](res/first_floor.jpg)
+
+# Structure
+The project structure consists of two blocks: car control (`Car`) and serial communication (`SerialTransceiver`).
+
+`Car` controls 4 wheels with tuned PID-controllers and calculates robot velocity by solving backward kinematics problem and robot position by solving forward kinematics problem (dedicated theory described in [Modern Robotics](http://hades.mech.northwestern.edu/images/7/7f/MR.pdf) book, p.519).
+
+`SerialTransceiver` receives control vector from Raspberry Pi (3 bytes) and transmits robot position in global coordinate system (12 bytes). It uses CRC8 algorithm to check message integrity.
+
+![UML diagram of GUI](res/UML.jpg)
+
+# Prerequisites
+This project was created using [PlatformIO](https://platformio.org/) IDE, so you need to install it to load code on your Arduino MEGA (or just copy all classes to Arduino IDE).