Calculated Imagination

Charlotte Folinus

student | engineer | tinkerer

I created two robots to score points on a Willy Wonka-inspired game board. One (above) used a rail climbing mechanism to ascend a 60º slope and an extending mechanism that could both lift an object and pull a lever. The other (right) used a telescoping linear lift to lift a 10 N gummy bear.

MIT’s pioneering 2.007 (Design and Manufacturing I) requires students to use materials from a universal kit to individually create robots which accomplish tasks and score points in a final competition. The game board my year, inspired by Willy Wonka (“Calculated Imagination” instead of pure imagination), featured many ways to score. Over the course of the semester, I used almost every manufacturing method available, from hand tools to the lathe and water jet. However, I relied heavily on rapid prototyping methods, particularly the laser cutter, to ideate quickly and test various designs.

I thoroughly enjoyed this project and both the freedom and responsibility it allowed me. I spent countless hours in the shop iterating through design concepts and refining my robots. By scoring in the top 16 students (out of ~150) during the semester, I achieved my goal of qualifying automatically to the second day of the competition. Despite issues with driving during my competition round, I am proud of my final robots as each of their modules worked smoothly and repeatably.

In recognition of my persistence and dedication to my robots, I received the Edison Award after the competition. I also received the Golden Broom Award from the shop staff for my commitment to maintaining the shop.

Ideation and Concept Selection

After performing initial calculations on points, torque, and power requirements, I used Pugh charts to select a strategy and later a specific design concept.

Experience gained from quick prototypes and CAD mockups of several ideas helped me choose the criterion for concept selection.

Pinch Wheel Extension

My second robot, designed to autonomously lift the oompa loompa before climbing the hill and pulling the multiplier during the manual control portion, utilized a pinch wheel and spring system to control the extension of a tape measure. A hook on the end of the tape measure allowed it to both attach to the top of the multiplier lever and to ascend the oompa loompa tube without buckling. The drive base features a rail climbing mechanism that lets the robot use the t-rail to easily climb the hill without tipping or slipping.

I experimented with a variety of hook shapes (top row) and ways to control the tape measure. The clear acrylic frame made the module easy to fabricate and understand. This allowed me to quickly add features, such as a tipper and a cut out to avoid collision with the rail when climbing the hill.

hook attachment

pinch wheel-spring system

rail climbing mechanism

CAD (Solidworks) was an invaluable tool in determining geometries. Climbing the t-rail required a narrow base to avoid collision with the other parts of the game board. I created a model of the t-rail (in brown) to determine proper rail grabber and motor placement.

While I made engineering drawings for the rail climbing mechanism's “skis," testing revealed a need for different geometries, which I achieved by sanding the pieces. I used the same hole pattern to create a variety of ski geometries.

Telescoping Linear Lift

My original robot, designed to lift the inner gummy bear, featured a telescoping linear lift and a robust drive base. My final design uses bended sheet metal frames separated by small pieces of acrylic which both provide a sliding surface and act as mechanical stops to prevent overextension.

I used my design notebooks for everything from brainstorming to engineering drawings and planning time in lab. I created Gantt charts to track project progress and then broke down these larger tasks into smaller items with accurate time estimates. For components with more complicated assembly, I made diagrams describing how to efficiently re-assembly my robots.

Project Planning