I took a class called Principles of Engineering in my sophomore year of college (2005-2006) at the Olin College of Engineering. The ultimate goal of the class was to introduce students to the engineering process, and over the course of the class create a product that was mechatronic in nature and controlled by a microcontroller. Me and a few other students (Matthew Aasted, Chris Dellin, Elizabeth Kneen, and Jon Tse) teamed up, approached Professor Gill Pratt for project inspiration, and decided to create snake robots in his newly-formed Biomimetic Robotics Lab at Olin.
We decided early on in the project to focus on a mechanical design unlike any other that we’d seen in a snake robot up until that point; instead of having a long series of joints, we decided to have a single elastic member down the entire length of the robot. Ribs attached to this ‘spine’, and hobby servomotors acted as muscles to push and pull the ribs against each other. This resulted in a robot that we call the ‘Serpentine Snake’ at the end of the fall semester of sophomore year, that moved forward by moving in a sinusoid from side to side and having passive wheels resist the urge to slip sideways (and instead, force the snake forward along its serpentine path).
Chris Dellin and I decided to continue the project after the fall semester as an undergraduate research project, and changed the design to allow for fully three dimensional movement – instead of only having muscles that allowed for side-to-side movement, we stiffened the actuators and gave the robot the ability to lift or lower its sections. This allowed the snake to achieve both a sidewinding gait and a rectilinear gait similar to an inchworm.
My role on this project was lead mechanical engineer and designer, responsible for the overall mechanical structure and actuation design of both robots. The robot parts were designed for lasercutter-based rapid prototyping.