Nudging the joystick forward on the video game controller in his hands, Aidan Flaherty watched as the foot-high robot in front of him sprang to life. In a whirr of electric motors, the metal bot dug its four rubber wheels into foam pads arranged on the floor and zipped across the makeshift pen inside Ridgefield High School’s robotics classroom.
The machine halted near one of the six-inch steel barriers set up in a square to pen the robot in. With a twitch of the joysticks, spun the machine around on its axis.
The 15-year-old high school tapped a button on the gamepad, and the robot lowered a metal arm suspended on elastic bands. Another button press set two cylinders at the end of the arm rotating. From his vantage point, the robot vaguely resembled a miniaturized combine-harvester.
With a flick of his thumb, Flaherty sent the bot in a semicircle around the pen, scooping up tennis balls strewn on the floor and depositing them in a cage in the robot’s body.
“We spent the first week building the arm,” said Ryan Crist, 14, Flaherty’s team mate who stood beside him as he directed the robot up and onto a set of platforms meant to test the robot’s agility.
They programmed the robot to drive like a tank — forward and backward on the left joystick controls the two wheels on the left, the right joystick controls the wheels on the right. Push one forward and pull the other back, and the bot will spin on its axis. “It seemed easier,” Crist said.
Crist and Flaherty’s bot was just one of the robots built by the students at Ridgefield High School for Robotics I, a one-semester course is taught by Michael Murphy.
On Friday, Jan. 25, his students were hard at work tearing their creations apart bolt-by-bolt, as the rest of the school took their midterm exams.
The end of semester teardown was a little sad, admitted sophomore Andrew Preston, 14, but it served a purpose. “We’re going to break it down and show our design process,” he told The Press, shortly before he and his freshman teammate, 14-year-old Will DeSpirito, gave a presentation on their creation. They decided to build a smaller robot they nicknamed “the protobot that could,” for a basic design Murphy had them build earlier in the semester.
“I feel like we could have made it a lot better,” Preston said. “It was supposed to be the underdog, but…” his voice trailed off.
The pair considered equipping the robot with an arm or a claw, but finally settled on a flipping armature for flipping over plastic caps in the pen — which “like three other teams stole from us,” DeSpirito said.
Robots were put together by the students from a mix of kits supplied by the school. Sections of metal framing came with pre-drilled holes for screws and bolts, allowing students to build a basic frame. From there they could add electric motors and wheels or tank-like treads for mobility, and arms or claws for grabbing objects.
“It’s sort of like the old-school erector sets,” said Murphy.
His first assignment for students had them building a simple drivetrain bot — essentially a motor mounted in a frame with four wheels.
Adding swappable gears between the motor and the wheels forced the students to learn about gear-ratios, Murphy explained. Students could gear the robot to zip around at high speed, but it wouldn’t have the power to hop up over obstacles. The same rules applied when students began adding armatures to complete challenges in the pen, such as picking up tennis balls and flipping plastic disks — lower gears would let their robot lift heavier loads.
“One of my goals is so that you don’t have to be a super nerd” to complete the course,” Murphy explained.
As students build increasingly complicated robots, they’re required to keep detailed notes of what they did, including pictures and videos of different versions of their robots. They also have to include notes on the computer code they write to teach their robot to respond to their commands from a video game controller, and work on its own.
It’s the less fun part of the course, Murphy admitted, but it’s there for “establishing good engineering principals.”
Besides Robotics I, Murphy also runs an after-school robotics club, where two robotics teams compete against those from other schools.
The school recently got the go-ahead to add Robotics II to the list of available courses for students next year. That class, which will also be a semester long, will teach students more advanced mechanical design. They’ll also learn more advanced ways to program the robots to work on their own without a human pilot.
Senior Austin Stietzel, 17, said the most challenging part of the course is getting a robot built within time constraints. Students have to “build it and code it for any issues,” he explained.
What kind of issues did the students encounter?
“Sometimes it would be a motor rotating in the wrong direction,” said Stietzel, who is also taking a course in computer science. Other times, pressing a button on the controller would make the robot perform the wrong command.
He said the course is flexible enough that it allows him to “get out of it what I put into it.”
“If I wanted to do something a little bit more advanced, Mr. Murph was really good about finding me an assignment,” Stietzel told The Press.
All of the students efforts culminates in a class-wide competition called Murfball.
Working in teams of two or three, students designed and built a robot from scratch; which they then entered in matches of two-versus-two robots. Students scored points for have their metal and wire creations complete tasks, such as climbing over obstacles, flipping over plastic disks, or snapping up tennis balls to deposit them in their team’s basket.
“We asked if we could steal from other baskets, Mr. Murphy said there’s no rule against it,” said Flaherty.
The class does not require students to have taken any prerequisite courses; “meaning students are not expected to come in with any prior knowledge and learn everything they need to design, build and program their unique creations in just half a year,” Murphy said.
Murphy said he encourages students interested in robotics to go on to take other courses the school offers in engineering, computer science, and digital electronics. Among the students who spoke to The Press, there was a wide array of interests that led them to the robotics course. Flaherty said he was interested in programming and artificial intelligence.
Stietzel, who said he’s interested in becoming a computer electrical engineer, said computer programming he learned in the course has helped in his computer science course, “but mostly it’s thinking through problems and solving them on your own,” he said.