Hit the Bricks
Programmable building systems can transform a class—from kindergarten to graduate robotics.
By Chris Rogers
The piece of technology that has most changed my classes is the LEGO programmable brick. Originally inspired by Seymour Papert and Mitchel Resnick at the MIT Media Lab, the idea of bringing together the physical (LEGO brick) and virtual (computer code) building systems has had a transformational effect in the classroom. LEGO has developed a number of these smart bricks (RCX, CyberMaster, Scout, Micro Scout, CodePilot, Spybotics, NXT, EV3, WeDo, and recently the WeDo 2) and a large assortment of sensors and actuators to enable students of all ages to design and quickly test their different ideas. Further, a number of other companies have developed “LEGO-compatible” sensors and actuators. From robotic zoos to Rubik’s Cube solvers to automatic fish feeders, the combination of the LEGO building system and an intelligent brick has allowed everyone from 3-year-olds to graduate students to learn engineering skills. LEGO is not the only company to make smart building systems; VEX, TETRIX, Fischertechnik, K’nex, and others have exciting systems as well. And then of course the Arduino network (including sensor kits like Grove) coupled with Open Beam, 80/20, or another building system, has introduced millions of students to engineering.
As a result of working with LEGO Education on the Mindstorms product for many years, I have heard teachers around the world describe how smart building systems have changed the physical learning environment and the very nature of the classroom, drawing in students who were previously not engaged (from kindergarten to college). Classrooms rapidly go from the teacher passing out the knowledge to the student discovering and sharing the knowledge. From first graders looking critically every morning at a graph of the temperature of an incubator to ensure the eggs will hatch, to eighth graders struggling with lighting issues when making an automatic sorting machine and college students building robots that can play the guitar, control puppets, or navigate a wheelchair by tracking the driver’s pupil motion, students are thinking like scientists or engineers, critically examining data or designs and searching for evidence to support their opinions.
Any of these systems allows students to think using their hands, test out ideas, and easily rip apart and rebuild. While computer-aided design lets the inventor iterate virtually with a mouse, LEGO bricks make the iteration a physical experience. Further, because there are so many different pieces, no two solutions in the classroom look alike. Suddenly, students become proud of their own innovations and creations. As soon as we see solution diversity in the classroom, we start to see students teaching each other.
Even in a graduate robotics course, I have seen students light up when I pull out LEGO sets. They wonder what this toy can teach them, but soon recognize its potential to help in robot design and algorithm development. Once we have some good algorithms, the students turn to Sparkfun or Adafruit boards with a Pi or a BeagleBone Black (almost the same brain as an EV3) to build a “real” version of their invention. The combined power of the LEGO set and LabVIEW or MATLAB drivers allows them to rapidly test and iterate before finalizing their design.
In bringing LEGO into the college classroom, the first question is how to keep the sets sorted. Some instructors rent the sets to the students, returning a deposit only when the set comes back sorted. Others have a lending library of sets and hire undergraduate sorters. My favorite scheme is to replace the LEGO sets with a much simpler set (EV3, motors, sensors, and chargers) and then give students access to a “LEGO Wall” where there are bins of axles, connectors, beams, and so on. This makes sorting and return very easy, especially if one treats the LEGO Wall as consumables.
The second issue is how to get students started. While some teachers have students follow directions for their first build, I prefer to hold a “Silly Walks” competition. Students have 30 minutes to build a robot that moves forward without using wheels. This exercise shows me the building skills across the class and gets everyone to turn a brick on, connect up motors, get software installed, and write a simple program, such as one that keeps motors running. The class ends with entertainment, as robots hop, lurch, or snake forward. For more complicated builds, students couple the EV3 with LabVIEW, MATLAB, or RobotC (or any of the many other programming languages out there—including a very nice Linux/Python option at ev3dev.org). Image processing, subsumption architecture, discrete controls, and home automation are all easily explored.
Although teachers must impart knowledge, it is equally important to develop students’ skills. Building systems provide a balance. A Chinese elementary school teacher summed it up best, telling an audience that one of the most successful classes he ever taught was one where he had to leave the room for 30 minutes after passing out LEGO sets. When he returned, the students taught him how to make a robot.
Chris Rogers is a professor of mechanical engineering at Tufts University. crogers@tufts.edu