Arduino light-gates

What is Arduino?

Open-source electronics platform 

Arduino boards are able to read inputs - light on a sensor, a finger on a button, or a Twitter message - and turn it into an output - activating a motor, turning on an LED, publishing something online. 

You can tell your board what to do by sending a set of instructions to the microcontroller on the board. 

To do so you use the Arduino programming language (based on Wiring), and the Arduino Software (IDE), based on Processing.

Over the years Arduino has been the brain of thousands of projects, from everyday objects to complex scientific instruments. A worldwide community of makers - students, hobbyists, artists, programmers, and professionals - has gathered around this open-source platform, their contributions have added up to an incredible amount of accessible knowledge that can be of great help to novices and experts alike.


What is a Light Gate?

A light gate has a beam going from one LED/IR light source onto a detector. As something goes through it, the beam is "Cut". 
The light gate measures how long the beam has been cut for. 

Some light gates will allow you to plug in the length of the crossing object, and then it an automatically calculate acceleration etc.

Our Light Gate

Parts List

MCU : 1 x Arduino Nano 
IR Receiver : 1 x TSOP38236 (or any TSOP382xx series should be fine. 
IR Sender : Any Infra-Red LED at around 940nm (940nm is the particular wavelength of infra red we are using, but anything around this should be OK).

Connection Table

Connected to
IR Sender LED Negative
Nano Gnd
IR Sender LED Positive
Nano D3 (PWM pin)
IR Receiver Negative
Nano Gnd
IR Receiver Positive
Nano +5v (VCC)
IR Receiver Signal
Nano D2