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 For the second consecutive year, South Dakota State University finished just short of winning the International Quarter-Scale Tractor Student Design Competition.

The ����ֱ��app Quarter-Scale Tractor Team, competing as the Jackrabbit Tractor Company, finished in a tie with Kansas State for second place. North Carolina State defended its 2024 title, finishing 26 points ahead of its Midwest competitors scoring 2,316 points out of a possible 2,405. 

The 28^th annual event was May 30-June 1 at the Expo Gardens Fairgrounds in Peoria, Illinois, with 23 teams competing from across the United States and Canada.

����ֱ��app has consistently been a leader in recent competitions. In addition to international titles in 2018, 2022 and 2023, ����ֱ��app has been runner-up in 2017, 2019 and 2025. In 2024, ����ֱ��app finished third with two points separating first and third place. COVID-19 canceled 2020’s contest. The 2021 contest was a hybrid adventure with ����ֱ��app only competing online and finishing fourth.

The team received a $1,200 check from the American Society of Agricultural and Biological Engineers, which sponsors the contest.

The tractors are essentially oversized riding lawn mowers. Each team receives a set of tires and a 31-horsepower engine; this year a Kawaski for the first time. Students are then tasked with designing, crafting and assembling the remainder of the tractor, which must hold up during durability, maneuverability and pulling tests.

In addition to points earned on the fairgrounds course, teams are judged on their written report and oral presentation as well as their entry’s appearance, craftsmanship and other criteria.

Tops in written, oral reports

����ֱ��app finished first in written report and oral presentation, scoring a perfect 500 points in each category. That was a highlight for club president Jaydon Estebo, who was part of the team for all four of his years at State.

The ����ֱ��app entry, nicknamed Bandit from the movie “Smokey and the Bandit,” was runner-up in the design category, gaining 416 out of possible 420 points. Estebo said judges were impressed by operator comforts on Bandit. For example, it has a custom air-ride suspension seat, and all the controls are in a central location on the armrest. 

“All the steering can be done by a joystick on the armrest,” said Estebo, who graduated in May with a degree in agricultural and biosystems engineering.  

Also this year, the ����ֱ��app team opted for a hydrostatic transmission rather than a manual transmission. “It’s as simple as driving a riding lawn mower. You push the gas and you’re going. The software is doing all the work behind the scenes,” said Estebo, noting this was particularly useful during the tractor pull.

Hydraulic transmission pulled well

����ֱ��app placed fourth out of 23 teams in the tractor pull. Among the five other entries with hydrostatic transmissions, ����ֱ��app had the best pull, Estebo said.

He said ����ֱ��app used off-the-shelf components — valving, hoses, pumps and motors — to develop its own hydraulic drivetrain as well as creating the software that guided the operation. As the load became heavier, the transmission would automatically adjust to provide more torque, Estebo explained.

“We learned that we had more torque than we needed,” so a future adjustment could be to sacrifice some torque to gain speed, he said.

Estebo, who now works as a design engineer at Vermeer equipment manufacturing in Pella, Iowa, said this is the first time in 13 years that ����ֱ��app has had a hydraulic drivetrain with its entry. He undertook the drivetrain as his senior design project and “thoroughly enjoyed … being able to work on an industry-level project and have the freedom to make important decisions that resulted in a successful final product.”

Into the repair shop

While the transmission performed well, the team did have an issue with a cast aluminum front suspension control arm.

On May 30, the team did a test run for the durability contest, which involves completing as many laps as possible in 20 minutes on a 250-foot course that included 80 feet of loose sand and 80 feet of rough conditions with a random array of six-inch bumps while pulling a cart loaded with 4,000 pounds.

One broke during the test run. That prompted a five-hour project that evening, working from the team’s portable shop/trailer to cut new suspension arms out of steel plates that are brought along and then reinstalling the arms. The next day, the entry was able to complete the course with no breakdowns, Estebo said.

In addition to Bandit, the club was able to bring its 2024 entry, make some comparatively minor revisions and compete in the X class, which is geared for freshmen and sophomores. The team finished second and was honored for having the best presentation.

While six students from this year’s quarter-scale tractor team did graduate, the 2024-25 roster included seven juniors, four sophomores and five freshmen. They are advised by Douglas Prairie, a lecturer in the Department of Agricultural and Biosystems Engineering.

The group also is varied in majors — ag systems technology, 7; ag and biosystems engineering, 10; mechanical engineering, 5; and precision agriculture, 2; and locales—Colorado, 1; Iowa, 3; Minnesota, 11; Nebraska, 1; North Dakota, 1; Ohio, 1; South Dakota, 3; and Wisconsin, 1.

The 23-member quarter-scale tractor team consists of:

Seniors

• Isaac Knobloch, Rock Rapids, Iowa 

• Jarrett Wildman, Farmdale, Ohio 

• Jaydon Estebo, Redwood Falls, Minnesota 

• Joseph Stumpf, Wabasha, Minnesota 

• Logan Turgasen, Richland Center, Wisconsin, incoming club president 

• Mark Hague, Highmore 

• Samuel Meyer, Mapleton, North Dakota

Juniors

• Brock Hansen, Good Thunder, Minnesota 

• Cameron Bennett, Bronson, Iowa 

• Dawson Gulizia, Gretna, Nebraska 

• Evan Madsen, Okabena, Minnesota 

• Ryan VanPelt, Austin, Minnesota 

• Samuel Nilsson, Mansfield 

• Trevor Sieberg, Minnesota Lake, Minnesota 

Sophomores

• Daniel Hetchler, Rogers, Minnesota 

• Joseph Mohr, Jackson, Minnesota

• Samuel Mastey, Belgrade, Minnesota 

• Trevor Werdel, Ree Heights 

Freshmen

• Andrew Schull, Mapleton, Minnesota 

• Blake VanPelt, Austin, Minnesota 

• Connor Fluit, Inwood, Iowa 

• Jack Forcier, Winsted, Minnesota 

• John Dexter, Delta, Colorado