Fish out of Water

General Description and Objectives

Created by David Perry, Hajin Kim, and Lissa Biltz, Fish out of Water is an interactive, fish robot on the Pololu 3pi robot platform.

The user draws various things on a whiteboard table, and the fish reacts to them appropriately.  On its own, the fish moves in a random, sinusoidal path.  However, various obstacles cause the fish to change it behaviors.  Darker and thicker drawings are considered major obstacles and threats to the fish, so it turns around and moves in a different direction.  Thinner lines are interpreted as beneficial to the fish, so the fish moves through them and makes happy noises.

Originally, our purpose was to make a robotic fish able to interpret user drawings exactly and emulate very real behaviors of a fish in a fish tank like environment.  However we realized that the 3pi platform would be unable to sense colors of whiteboard markers easily,and that the behavior of the fish would be too repetitive too quickly.  While the user can overall trigger various reactions from the fish, there is a lot of ambiguity in what the fish will decide is a thick or thin line, emulating the fact that the fish has free will.  Also the appearance of the fish is not meant to replicate any species of fish specifically.  So as each user draws and discovers the reactions of the fish, they are creating their own environment and specific fish in the water.


Some people consider looking at fish as a relaxing activity.  Amidst the stress culture of CMU, Fish out of Water was designed to calm students down in ordinary places, such as a library or a residence hall.  However, since user’s drawings are what influence the fish’s behavior, experiences and result change from person to person.

Work Distribution

David Perry- Created the default path for the fish.   Programed the sensors on the 3pi to recognize the difference between thin and thick lines.  Programmed the behavior of the fish.

Hajin Kim- Designed the overall appearance of the fish through various prototypes.  Laser cut and fabricated the fish.  

Lissa Biltz- Wired the LED, explored fish sounds, Programmed behavior of the fish.

Initial Prototype

Initial prototype. T  Initial prototype. Top viewInitial Protoypep Side ViewFinal Product

img_1957 img_1958 img_1959Technical Documentation

Circuit Diagram


Link to download source code and dxf file


Leave a Reply