The goal of project projectile, for engineering teacher Lance Sawyer, was to teach students to eliminate variables in a project through multiple variations of trial and error.
His students may not have noticed the lesson because they were having fun. Graham Pankratz said the projectile-launching competition to take place today in the Hillsboro High School gymnasium has become a point of pride for the students involved. The goal is to launch projectiles across the gym floor and land them within a 10-foot surface.
“It’s almost like a sporting event,” Pankratz said. “There’s a little bit of trash talking.”
Pankratz, Tyler Funk, and Kale Arnold constructed a potato gun launcher with PVC pipe mounted on two sliding rails to adjust the angle. The gun is powered by an air compressor that shoots golf balls wrapped in padding and T-shirts. Hillsboro basketball fans may have noticed Arnold using the gun to launch T-shirts into the stands at recent basketball games.
The students had six weeks for the project. Pankratz said it took about three weeks to construct the launcher. They conducted testing for about five days. He said one problem his group encountered was finding 3-inch PVC pipe to try to shoot a tennis ball. They discovered no place in town sold such pipe and had to adjust their projectile.
Pankratz, Arnold, and Funk never wavered on their choice of launcher, only making slight modifications on their potato gun idea. The group of Jordan Bezdek, J.D. Schmidt, and Caleb Bettles had to change their launcher several times in the process.
An original crossbow idea was scrapped for a catapult construction. The group used two different launching arms. The first was made of wood with a melded metal cup for a tennis ball. That arm broke once the team switched from bungee cords to springs to apply more power. They then decided to make a sling shot inspired arm with PVC pipe and string. Bettles said the arm mirrors a pitcher delivering a strike to home plate.
The Bezdek, Schmidt, and Bettles group put their catapult design through a myriad of tests at each stage. The wood base had notches built in to adjust the angle of projectile flight. They found that with the arm loaded in the furthest front position the projectile flew the farthest with little arc.
Bezdek and Bettles showed more interest in the project because they plan to pursue engineering in college — Bezdek, architectural and Bettles, computer engineering.
Schmidt said he enjoyed the project just because he likes to build stuff. Pankratz and Funk both added that they enjoyed the project because it was a removal from normal classroom activities.