Cat’s Out of the Bag (Halloween Project)

For this project, I wanted to portray themes of nostalgia and unpleasant truths. I used a toy from my childhood, and augmented it, turning it into something slightly horrifying and much different from my idealized memory of the toy.

I started by trying to reverse engineer the toy and learn how it worked mechanically, so that would know what wires to change to suit my needs.

The toy features 5 capacitive touch sensors, a speaker, and two servos. I decided I wanted to ‘trigger’ different actions of the cat, and to do so I made a control panel with conductive tape that would allow a user to trigger different actions and play noise. These actions are Hiss, Purr, Meow, Look Left, and Look Right.

I had hoped to circuit bend the speaker board to get interesting results, but unfortunately most of the speaker timing and signal processing were in the IC, and I was not willing to mess around with the whole board due to the motor control circuits on the same pcb, as I was afraid of shorting out important components.

Instead, I made an external pitch shifter using an Atiny85, the circuit and code for this board can be found here:

I soldered the components to a protoboard and broke out the speaker wires for the cat toy, also soldering them to the board. I then added two buttons to allow the user to change the pitch manually, and mounted them to a control box.


I'm a computer and electrical engineer interested in robotics and technology as a medium for art. Alternate email:

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