how to communicate with 32- bit controller and ROs running on PC over USB via UART

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Hello,

I am a newbie to the ROS, want to use the ROS for an indoor navigation robot which goes as below:

indoor navigation robot, which has sensors like stereo camera’s, ultra sonic sensors, kinect, encoders for the motors etc. which are all connected to a 32-bit micro controller (Atmel), all the commands for the actuators will be given by this controller, and the data from all the sensors are read by the controller (using SPI, UART I2C etc.).

I want to send the Sensor dat to the PC (running with ROS on Linux) fixed on to the Robot and use the libraries for navigation, mapping etc. available in ROS.

But my first question is How can I send the data from the micro controller to the PC, I have Checked over the internet, The option was to use the “roserial” library.

I can use the available UART port on my micro controller, but How can I transmit this data to PC which will be connected via a USB.? How can I open a USB port on the PC and send data on that port, which should be received by the micro controller on the UART..?

Many Thanks in Advance.