Robotic car

Building a Better Robot

By


Twelve hours. 

That’s how long it took to undo almost two semesters worth of work.

When a pair of student teams from the University of Central Arkansas traveled to compete at the National Robotics Challenge in Marion, Ohio, one of the teams unpacked their bags after the 12-hour road trip only to find disaster staring them in the face.

“On the way to Ohio, we traveled in a 15-passenger van and our robot was in the back of it,” said Corbin Humphrey ’22. “When we got there, we saw that one of the capacitors on one of the motors had broken. It was just dangling by a thread.”

Thankfully, the team had brought a soldering kit and the tools needed to make repairs. As the teammate with the best soldering skills, Chris Geske stepped up to re-attach the capacitor to the motor. With that potential crisis averted, the team was ready to jump into the competition.

The National Robotics Challenge began in 1986 with just two events each for high school and college competitors. In the more than 35 years since, the competition has grown to nearly 30 events for students at the university, high school and middle school levels.

2022 marked the first year UCA students have participated in the competition, thanks in large part to a grant from the Arkansas Space Grant Consortium. The students also got support from William Slaton, director of the UCA engineering physics program and Carl Frederickson, chair of UCA’s Department of Physics and Astronomy.

At the competition, which was held in April 2022, students from Lin Zhang’s Engineering Physics Senior Design class took part in the Autonomous Vehicle Challenge against teams from Kansas State University, the University of Texas-Arlington, the Polytechnic University of Puerto Rico and the South Dakota School of Mines and Technology. 

“Nothing worked right out of the box. But that’s engineering. You can’t be discouraged. If things aren’t working, you have to spend the time to figure them out. And our students, they never gave up when things weren’t working. They just kept trying hard to solve the problem.”

– Lin Zhang, assistant professor of physics and astronomy

The two UCA teams spent the fall and spring semesters designing and building robots that could navigate an outdoor obstacle course in under five minutes with no human input. Both teams used a Raspberry Pi system as the “brains” of their vehicles but, beyond that, their approaches to navigation went in completely different directions.

The Robot Ninja team was comprised of Humphrey, Timon Dresselhaus ’22 and Ole Kjorholt ’22, all engineering physics majors who graduated in May 2022, and Geske, who plans to graduate in December of 2022. They installed an Arduino system and relied on GPS to guide their vehicle. Using real-time satellite data, the GPS system would determine the position of the robot and then tell it which direction to move.

Gavin Epperson ’22 and Daniel Ashcraft ’22, both computer engineering majors and also May 2022 graduates, made up the Donkey Car team. They used the open-source Donkey Car platform and an on-board camera for their robot. Essentially, the team would drive the vehicle around the course during practice laps using a remote control, modeling what they wanted it to do on its own. The robot would take nearly a thousand pictures per minute and then use that data during the competition to steer itself around the course.

But even with months of work under their belts, both teams had to make adjustments right up until the last minute.

“The day of the competition, we were still modifying our code,” Humphrey said. “Even when we were outside on the course, we were adjusting the robot and how it was performing. Timon was tweaking the design of the vehicle the entire day because it needed to be waterproof.”

UCA students posting with their award from the National Robotics Competition
Lin Zhang, assistant professor of physics and astronomy (left) with Christopher Geske, Timon Dresselhaus, Corbin Humphrey and Ole Kjorholt celebrating the 3rd place win. Humphrey is holding their autonomous racing robot: NinjaBot.

“We were already a little nervous going in,” added Dresselhaus. “And then it started raining. Then it started snowing. Later in the day, it was extremely sunny. The weather was just crazy.”

The parking lot at the competition, where the obstacle course was laid out, didn’t help matters either.

“We were expecting at least a flat, straight surface but this thing had holes and bumps in it,” Dresselhaus said. “In one part, it almost looked like the ‘bot was climbing a mountain. That also contributed to us making some of the last-minute changes.”

Thankfully, all those last-minute modifications paid off. The Robot Ninja team took home third place at the competition.

“We didn’t think we would place that high, especially our first year going,” Dresselhaus said. “But it was cool to see the hard work pay off.”

Even better, the Donkey Car robot built by Epperson and Ashcraft (and assisted at the event by fellow UCA student Austin Miller) captured top honors. They were also the only team to complete the entire obstacle course.

While taking home first and third place from the nation’s oldest robotics competition was certainly a tremendous success, Zhang had a slightly different perspective.

UCA student Austin Miller works on a robotic car
Austin Miller works on the new generation of the autonomous racing robot for 2023’s challenge.

“I didn’t think we’d get first and third place, so that was a nice surprise,” said Zhang, an assistant professor of physics and astronomy in UCA’s College of Natural Sciences and Mathematics. “But I more valued the process the students went through. They were dedicated to this project and showed off their intelligence and their determination. 

“Nothing worked right out of the box,” Zhang added, recalling the early days of the build process for both teams. “But that’s engineering. You can’t be discouraged. If things aren’t working, you have to spend the time to figure them out. And our students, they never gave up when things weren’t working. They just kept trying hard to solve the problem.”

Humphrey agreed and offered his advice for future UCA robotics teams.

“It’s going to be hard and you’re going to get frustrated,” Humphrey said. “We hit a lot of walls – there were times we had to ask for help. You can’t let that stop you from learning and giving it your best shot. It’s not going to be easy. But everything we went through, it was all worth doing.”

Originally published in the Fall 2022 edition of UCA Magazine.


Categories:

,