Woodpeckers have two different types of pecking that they use for two different reasons. The first type of pecking is characterized by hard, randomly timed pecks, and is used for digging into wood surfaces to look for bugs or to make a nest. The second type of pecking is more of a drumming, and is the woodpecker's version of bird song. This drumming is far faster and is done in a rhythmic pattern; the birds usually find hollow wood to increase the volume and echo of their songs. My goal for this project was to mimic both of these behaviors, and to make the user feel as though they could have a call-and-response with the woodpecker. Project code can be found here.

Woodpecker from Martin Bernard on Vimeo.

The peck is more of a full body motion for the bird, which I though could be mimicked with the servo motor, but the drumming is more of a rapid neck motion, and I found the servo motors were too slow and clumsy. A small pull-solenoid fit my purposes well instead, both creating a mechanical beak and creating a noise that differed from the regular pecking.

Early versions of the mechanical woodpecker used single mini-servo motors, but the servo arms were not sturdy enough to withstand the somewhat violent pecking, so replacing the individual motors with a pan-and-tilt motor kit made the structure of the bird far more reliable.

The robot’s final form was a wooden box, with the bird form made of card stock on one of its longer flat sides. When turned on, the bird pecks randomly on the left side of the box. When a user knocks on the box loud enough, the bird pauses, registers the call, and drums back a response.

Future iterations of the project would be useful in further developing the bird's form. The bird’s weight was not easy for the servo-motors to move precisely, resulting in movement that could sometimes be clumsy. Replacing the card stock could improve performance as well as contribute to a more finished look to the robot.

Materials - 1/8” plywood, card stock, CPX, Crickit for CPX, pan-and-tilt servo motor, solenoid

Instructor: Phil Van Allen

Create an interactive piece that uses one or more servo motors to create something that feels alive. It must be based on research inspiration, where you find an example of something alive that behaves through movement.

This project builds on the previous emotion project ideas. But in this project, the physical movement provides the primary mode of expression. The expressive movement can indicate more than emotion, and can be functional (like looking up), or communicative (like shaking left/right to indicate “no”).
This project needs a strong concept as well as thoughtful design and form making – it is not only about technology. Having wires hanging out all over is not acceptable – you must create an enclosure. In other words, the project should feel finished and refined.

-Have more than one type of movement – this creates a much -greater sense of life
-The servo must be attached to something that it moves
-The movement must be altered based on input from a -sensor(s)
-Avoid literal human faces
-Use more than one sensor and/or more than one servo