To allow Twitr_janus to react to its surroundings it needed to be able to sense them. The simplest way to do this was to use a webcam with a built-in mic. This enabled the puppeteer to remotely see and what Twitr_janus could see and hear.
The eyeballs are made from deodorant balls, which conveniently are hollow. As well as being easy to cut open, they are also rigid and do not deform if you cut bits off them.
They also come with ready-made housings from the bottles they are contained in. These were cut off and glued into the back of the eye sockets of the puppet face mask.
Below you can see the exploded eyeball, the Microsoft LifeCam and the control rod. This is used to add leverage. Later the rods from the two eyes are jointed into a rig, that is attached to the servos to allow position-control...
To make Twitr_janus see, Skype was loaded onto the computer that was attached to the puppet head. Skype was signed into a specially set up account. Skype can be set to be woken up from standby and to connect to a call just by dialling it. You can also specify that only specified Skype contacts can do this.
The net effect was that it was possible to wake up Twitr_janus' webcam eyeball. The webcam also had a built-in microphone. This meant that it was possible to activate both sight and hearing remotely inside the puppet head from a remote location, as long as the control device had Skype loaded and was logged into an account with permission to activate the Twitr_janus Skype account.
In this picture, the web cam is being tested by aiming it at the Arduino...
And here you can see an iPad (left) being used as a remote control. It is making a Skype call over the web to the computer (right) to which the eyeball is attached. The close up of the Arduino on the iPad is what the eyeball on the floor is pointed at (slightly dark, in the centre).
Here you can see the webcam still in its original casing being tested for rotation clearance inside the face mask. You can also see the hot glue and the reinforcing plastic gauze used to provide strength.
Here are the two eyeballs inside the skull. They are fixed into a jointed parallogrammatic rig. The two control servos are visible.
the servo to the left of the picture inside the rig, causes left-right motion by shearing the rig parallelogram, which is partly made up of the eyeball control rods (as above).
the servo to the right is coupled to the rig via a flexible, but rigid bike cable, via which it controls up/down motion.