|A robot moving along a bar towards the items it is required to retreive and recycle.|
San Diego, CA, August 20, 2015 -- Each year, hundreds of UC San Diego students turn out for the Introduction to Engineering Graphics and Design (MAE3) robot competition in the main gym on campus. There are robots that grab, push and pull and even some that are made for the sole purpose of distracting the opponent. The competition stands in place of a final exam and results in bragging rights that students take seriously.
For the Spring 2015 quarter, the students in MAE3, taught by mechanical and aerospace engineering professors Nate Delson and Mike Tolley, were tasked with designing a robot that can “recycle” – or rather, move items from a small staging area representing their dorm room into the correct recycling bin a few feet away.
Designing and building these bots required undergraduates at the Jacobs School of Engineering to apply their machine design knowledge and dedicate time to learning how to use the fabrication tools at their disposal.
This year, for the first time in MAE3, students learned to use 3-D printers to print parts for their robots.
“The students were way ahead of me on this one,” said Delson, who is also the Director of UC San Diego’s Mechanical Engineering Design Center. “My TA, mechanical engineering graduate student Daniel Yang, actually purchased his own 3-D printer and convinced me to incorporate it into the MAE3 curriculum. When Dean Albert P. Pisano presented his plan to increase hands-on education, adding the 3-D printing to MAE3 became our highest priority.”
The plan Delson referred to is the Experience Engineering Initiative, which aims to give all Jacobs School undergraduates hands-on engineering educational experiences all four years. Over the 2014-2015 academic year, academic departments across the Jacobs School began developing and implementing Experience Engineering pilot courses that will roll out to larger numbers of students in the coming years.
Read more about the Dean's Experience Engineering initiative in the Fall 2015 issue of Pulse at pulsemag.ucsd.edu
“This is a memorable class because it’s the first time many of these students are exposed to the resources they have as engineering students at the UC San Diego Jacobs School of Engineering,” said Yang who is motivated to push the students to design and build great robots.
Yang’s vision for MAE3 mirrors an important aspect of the larger Experience Engineering Initiative: to give undergraduate students entering the Jacobs School hands-on experience and access to tools right from the start.
“We changed the curriculum for this course in order to incorporate the 3D printing,” said Delson. “Instead of waiting until week five to introduce 3-D CAD, we do it in week one, and by week 2 each team is printing their first 3-D part.”
At the beginning of the quarter students formed teams and used 3-D CAD software to start conceptualizing parts for the robot they’ll take to the competition at the end of the course.
“They’re free to print motor mounts, gears, pulleys, ball casters and anything else they can think of,” said Yang.
Early on, one group printed a modified motor mount with the hope of increasing the speed at which their robot performs the task.
“The idea came to us while we were solving a linear slider problem on a lecture assignment,” said Delta Caraulia, a first-year mechanical engineering major. “We realized that if we modified the width of the part, we could reduce the amount of friction: the wider base better supports the moments in the part and reduces the normal forces and friction in the bearings.”
Caraulia’s experience highlights an important goal at the Jacobs School of Engineering – to empower students to use engineering theory learned in class to solve real problems.
In past quarters, students used a 2-D laser cutter to cut the parts out of large sheets of plastic. Parts like hinges aren’t 2-D and required multiple steps to assemble – a problem that is solved with the use of 3-D printers. However, the 3-D printers present their own challenges.
“We printed a part that will slide along a bar to give our robot greater reach,” said Phil Gresser, a first-year mechanical engineering student in the class. “We left room for error but didn’t account for the expansion of the plastic due to the heat from the printer.”
Gresser is part of a team of three that held up their obsolete part to the class during a progress report during week six of the course.
“What did you learn?” asked Delson.
“We learned that we needed to increase our tolerance level even further,” said Gresser. “Next time, we’re going to print a small cross-section and test it before doing another six-hour print!”
Delson gave an approving nod. “Don’t discard an idea too quickly,” he said, turning to the rest of the class. “The truth is, we don’t know what will or won’t work in this competition.”
The Design Studio
The laser cutter and robot staging areas are housed in the Design Lab – a space that Nate Delson created along with Chris Cassidy 10 years ago to teach students hands-on design.
Chris Cassidy oversees the space.
“I have a cool job,” said Cassidy. “I get to help students drill or tap a hole for the first time.”
Cassidy says that it sounds simple, but these students are learning to actually design and make their own working machine; something most of them have never done.
According to Cassidy, 3-D printers are a different animal. Lasers can cut out parts quickly, but 3-D printers build up a part layer by layer, which may take hours. Also creating the computer models for 3-D printing is much more involved, but is an essential engineering skill to learn.
“They fit well in the education space,” said Cassidy. “The printers we have do not always yield high quality prints, but that makes them better for teaching because the students learn how to leave room for error.”
The MAE3 Robot Competition took place on June 9th at UC San Diego.