MECHANICAL ENGINEER
Pitfall (MIT 2.007)
The Game
The game for the 2017 2.007 competition was called "Friction Wars - May the Torque be With You". Inspired by Star Wars, players were given several different ways to score points. I chose to focus on spinning two heavy thruster wheels located on the first and second level of the game board.
Elevator
in order to reach both the top and bottom thruster reliably, I decided to design an elevator mechanism. Since our robots were required to fit within a 16" x 16" x 16" starting volume, I was forced to make a three-stage elevator in order to reach the entire distance. The elevator consisted of three stages, each made out of folded aluminum sheet metal. These parts were designed with linear guide slots that interlocked with plastic bushings attached to each of the stages, allowing them to slide up and down. The elevator was powered by a winch system driven by an LDO motor with a 26:1 planetary gearbox. The winch used two cables, allowing for the elevator to be back driven. I manufactured the elevator slides and cross pieces using a water-jet cutter and created the pulleys for the winch system using a lathe.
Spinner Gearbox
The second important component of my robot was the custom gearbox used for the spinner. To calculate the gear ratio, I created a Matlab script that took in the properties of my motor (stall torque and no-load speed), the number of motors I was using, and the moment of inertia of the wheel I was turning, and output a graph of wheel speed over time. Using this model, I decided to use two motors with 26:1 planetary gearboxes, connected together with a 2:3 gear reduction, as it allowed me to reach the max speed of 25 rad/s in a reasonable amount of time. I designed my gearbox inSolidWorks, water-jet the gearbox plates out of aluminums, and created the tapped aluminum standoffs using a lathe.
Results
My robot performed well in the final competition. I won my preliminary matches and qualified for the elimination rounds reserved for the top 16 out of 165 total competitors before eventually being eliminated. Over all, this project allowed me to gain more hands-on experience in all aspects of the design process, and was a lot of fun as well.
About the Project
This project was made as the term project for 2.007: Design and Manufacturing I. Each year, students in the class individually design and manufacture remote-controlled robot to compete in a game designed by the course instructors.
