I am working on different options for the head or face of my 15 DOF robot. Today I got a MAX7219 8x8 LED array working with it. Over the years I have made heads out of Christmas ornaments and some LED's. But they cannot change their expression. Now I have added a MAX7219 so the robots expression can change with every command that you send him.
This picture shows some of the robot heads I have made for my robots with the MAX7219 version in the middle. As you can see the 8x8 LED array is a little on the small side. I have some bigger LED arrays that are two and three color, but without the MAX7219 I do not have enough pins left over on the Arduino processor to run them. Data TX and RX + 15 servos is 17 Pins leaving only three pins that are available to control the face.
|Max7219 Humanoid Robot Head|
The video is up on YouTube: