MEGR 3156 - Junior Year

In the spring semester of 2009 I enrolled in MEGR 3156, also known as Junior Design. The project details can be found below.  I have included the rules, regulations and pictures of the end result.

At the end of the semester all the teams (from 3 different classes) competed against each other in a time challenge. Our team did will in the time challenge and placed 5^th overall.

A few details:
Each class was divided into teams of five to build a robot that had to travel over an obstacle course and complete a certain task at the end of the course and then return to the start point.

This year's class had to build a robot to deploy a bridge that was to be carried on the robot. After getting over the various obstacles it had go up a 30 degree incline that was 2 feet high and then deploy the bridge over a 9 inch gap at the top. The robot had to cross the bridge, then pick it back up and continue around the rest of the course to later turn around and complete the course in the opposite direction.

Normally the budget for the vehicle is in the $200.00 range. However, with the economic down turn and Dr. Lawton decided to give us a real life example and cut the budget to $170.00. There were a few other details involved regarding the cost but the main objective was to design a vehicle from scratch and to calculate all the stresses, torque and failure modes of the vehicle with the engineering knowledge we had at the time.

Below, are a few pictures of the course.  The starting position can be seen in the foreground via the taped off rectangle. This was also our maximum size envelope. The robot had to fit within the tape.

The blocks that were painted green where set as barriers that we had to navigate around and could not cross. All other obstacles could be traversed. 

After the robot crossed the gap, it had to continue up the incline and navigate through the vertical pegs before turning around and completing the course in the opposite direction.

Below are a few pictures of the robot after completing the competition.

The bridge was made of 2 sheets of "pre-preg" carbon fiber with a 1/8" thick honeycomb core between the sheets. The bridge was load tested for 10 pounds and deflected only a fraction of an inch.

(Bridge testing was part of the project)

The wheels were made on one of the 3D printers at our disposal with our team logo as the spokes. The rubber that is attached came from 1/8^th scale off road buggy tires. I was able to treat the rubber using techniques from my racing back ground to make them extremely tacky. This aided the robot in the climbing portion of the challenge. 

Using two worm gears the robot was able to pick up the bridge from both ends of the vehicle by using the fork tines that were machined out of ABS on a 2.5 axis plastic CNC.

The robot was controlled by a PID controller that my teammates Omar and Ed designed.

In addition, the controller, which was Omar’s project, was made using the SLS 3D printer. 

This design started by molding a brick of clay to the desired shape. It was later scanned using the 3D laser scanner to create a model for the 3D printer.