The Arduino Nano and Ten CdS Photoresistors are combined to realize an Optical Flow Sensor.


Nine diferential measurements are obtained from every consecutive pair of photoresistors (edge detectors).

Digital pins are used as outputs  to produce +5Volts and Ground, and as inputs to produce High impedance).


All the signals are captured in the analog input A0.


Based in the work of Geoffrey L. Barrows, Centeye, Inc. Simple optical flow sensor using 18 CdS cells.

The getImage() function was modified to  capture data.

Search for “Optical Flow with Aduino NANO”  in   pastebin


The assembly procedure and test results can be seen in Youtube:

Aditional Tests made with the “Optic Flow Sensor”: