PLTW: Motion and mechanisms

Posted on: May 26, 2022

Eighth-graders in the Project Lead The Way Automation and Robotics class recently gained experience in constructing pull toy mechanisms.

Pull toys transfer input energy from rolling wheels to power output movement in other parts.

“In this class they learn about and build 12 different mechanisms,” said instructor Tory Spanier. “We talk about types of motion: rotary, reciprocating, oscillating and more, so it’s kind of physics-related that way. Then they have to apply it.”

The challenge for the pull toy project was to piece together a mechanism that would appeal to elementary-age students, then put it to work in a Pull Toy Parade across the shop floor. Students had about a week to design and build before the parade on Monday, April 11.

“They build it from scratch. They have to configure all the different parts and put it all together to make it work,” said Spanier. 

By the time they get to the project, students have already learned about gear trains and how to adjust speed and torque. 

“If you’re riding a bicycle going uphill, how do you increase speed? How do you increase torque to make it easier to pedal up the hill? If you’re geared for speed it’s hard to pedal, so you change gears. Just getting them to understand that is the first part,” said Spanier. 

Students also learn about bevel gears that can change the direction of motion. 

Mylie Pinoniemi and Kaia Georges made one of the more impressive pull toy designs, with a rotating Christmas tree built on the standard four-wheel chassis. Although the students put the design together from a sketch Georges created, and most of the construction was fairly straightforward, the rotation of the tree took some fine tuning.

“Mr. Spanier said that the bevel gear was going to be tricky, to make (the motion) go a different way. It was hard,” said Pinoniemi. “The gears were rubbing against each other so it wouldn’t turn, so we had to space them apart.”

Thomas Myhervold, Hunter Hansen and Daniel Halonen built a unique toy that moved on treads like a bulldozer or tank rather than wheels.

“We had some extra time and we wanted to be more unique than some of the other ones, so we decided to do tracks,” said Myhervold. “We saw them and just thought it would be a cool idea.”

While the students had already learned about individual mechanisms, they enjoyed combining them into a functioning machine.

“This was just putting them together and learning how they all work together,” said Myhervold.

“It was pretty fun,” said Hansen. “It was interesting looking at other people’s creations as well.”

While there was a definite objective, students appreciated the opportunity to use their own imaginations on the final product. 

“I enjoyed the freedom to design whatever we wanted,” said Kaelyn Wittwer. 

Spanier said that flexibility was important to the overall project experience.

“You give them the resources and they figure it out,” he said.

• To watch a video of the Pull Toy Parade, see bit.ly/PullToyParade.
 

Post Categories: High School