Last week in networked objects, we were required to make a physical interface for playing a networked pong game. There existed a server for the same running in processing, which would accept multiple incoming network connections. We were required to make an interface which would allow us to connect to the server, pass ‘l’ and ‘r’ values to move the paddle left and right respectively and to disconnect from the server if required. The main purpose of the assignment was to understand how to connect micro controllers to the internet without the use of a computer.
The interface that I came up with, looked like a big pulley, with a string on either side. The pulling of the strings on either side determined the direction in which the paddle would move. Also there was a single button used to connect to the server. Once connected an LED would light up show the connected status. The same button would be used to disconnect from the server if required.
On the technical end, the pulley is mounted on a potentiometer, which in turn is connected to the arduino input pin. The arduino regularly reads the value from the potentiometer to determine the position of the pulley. Based on a threshold, it would understand in which direction the pulley has been pulled. The arduino on the other side communicates over the internet using the Xport. There are 4 LEDs (controlled by the arduino) on the board to signal the status of connection, and the direction of the pulley.