In Physics Classrooms, MarkerBot Draws Up a Perfect Teaching Tool
In a physics classroom, few instructors can claim to perfectly draw a problem on a whiteboard. But in many situations, the accuracy of their drawings can make an important difference in the ability of their students to learn.
Now, instructors have a new tool at their disposal to “print” problem sets on a whiteboard with accuracy and ease, automatically.
MarkerBot, an innovation developed by Landon Hunter, an engineering student at Rogue Community College and competitor in this year’s Invent Oregon Collegiate Challenge, is an automatic whiteboard writing robot designed for instructors to use on classroom whiteboards.
The idea: use the same technology in a printer on a vertical surface with a dry-erase marker.
A member of Rogue Community College’s engineering club, the idea evolved out of Hunter’s studies with club advisor and professor James Rittenbach, who goes by the nickname Dusty.
“Dusty really likes to use whiteboards for his classes. If we have something that can kind of automate that and turn it more into a slideshow of you push a button, it sets up the framework,” Hunter said, “we thought something like that be really cool.”
But accurately reproducing an image where proportions have mathematical significance is as challenging as it is time-consuming. The MarkerBot will make it easier for instructors to set up visual problems by automating the entire process.
“A lot of things in physics are really awkward to draw,” Hunter said of Rittenbach’s classes. “But even drawing good straight lines can be kind of time consuming because you have to hold the yardstick with one hand, try to keep it relatively level, try to draw the marker across it."
A solenoid, for example, is a coil commonly used in physics classes to demonstrate how magnetism works. "If you want to draw the magnetic field going through a coil of wire by hand on the whiteboard, that's really hard to do.”
With MarkerBot, instructors can eliminate the time and error inherent in hand-drawing problem sets on whiteboards.
For the most part, this isn’t a significant problem for many instructors, Hunter said. But when problems become more complex, as they do in advanced classes, it also becomes more important for problems to be rendered in a way that is easy to understand. Sometimes, the human hand is too imprecise.
“Especially when you start moving to upper level calculus classes and upper level physics classes, actually, it's really, really hard,” Hunter said. “Something good is hard to draw in such a way that you can really tell what they are.”
We aren’t talking about parabolas and circles. Hunter points to the Bessel function, a visually complex mathematics used to describe the way waves propagate through a medium.
“There are a lot of functions that have really certain specific shapes that you kind of have to see the profile of to really get how they work,” Hunter said.
In years past, we used overhead projectors and devices like Elmo, which reproduce hand-drawn visuals on a flat surface, but they come with problems. Drawing by hand on a flat surface is only marginally more accurate than drawing vertically. And these projectors aren’t cheap.
“One of the real reasons why I thought about building this robot in the first place is that projector's sets aren't cheap and Elmos aren't cheap, like they're really kind of high-end,” Hunter said. The cheapest Elmo, essentially a digital overhead projector, costs almost $200.
Hunter expects MarkerBot to cost less than half that. “That's really affordable,” Hunter said. “If you're a school that doesn't have all this available, then having a really low-cost option could be really appealing.”
MarkerBot can do this because, like the best innovations, it is a simpler device. The device consists of two spools of wire that are controlled by motors. The wire from the spools attach to a marker, and the action of the spools controls the marker’s left and right movement. Gravity and tension control how the marker moves up and down.
“Part of why the MarkerBot is such an interesting idea to me is that, fundamentally, it is a really rudimentary CNC machine,” Hunter said. A CNC machine, short for computer numerical control, automates the use of machining tools like drills, lathes or mills.
The same technology created printers, and Hunter built MarkerBot on the same backbone. “Before we had printers, we had basically drawing robots for drawing blueprints,” Hunter said. “They actually had a little pen chip and they would just go round and draw.”
The technology has evolved considerably, and printers can do much more than they used to. But the framework, according to Hunter, is essentially the same. He simply translated the same idea into MarkerBot.
Because of this, instructors can illustrate a perfectly rendered Bessel function on their computers. With the right software, they can use the MarkerBot to print that function on a whiteboard. It really is that easy.
And students will end up smarter for it.