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University of Iowa News Release

July 9, 2003

(Click on photos for high resolution images: Top--Matthew Christiansen's Sweep Stopper (the red plate on the side of the grain bin) is designed to stop the "sweep" to give workers inside the bin a safe exit. Middle--A close up view of Matthew Christiansen's sweep stopper shows how it stops a sweep inside of a grain bin to allow a safe exit. Bottom--Matthew Christiansen of Scranton is shown with his display that explains how his invention, the Sweep Stopper, operates.)

Grain Bin Safety Sparks Young Inventor's Imagination

Many children dream of inventing fantastic contraptions. When Matthew Christiansen dreams up inventions, they're not only practical -- they're being used.

One of Matthew's inventions, The Sweep Stopper, makes cleaning out grain bins - an often-dangerous chore because of internal machinery that can injure a person - a cinch, and it's already been installed in bins on his family's farm. The invention also won a $500 scholarship at the Invent Iowa competition held in April at Iowa State University. He'll get the scholarship if he enrolls in the College of Engineering at either the University of Iowa or ISU.

Matthew is the son of Glen and Cathy Christiansen of Scranton and will be a seventh-grader at Jefferson Middle School this fall.

The Invent Iowa Program is sponsored by the Connie Belin & Jacqueline N. Blank International Center for Gifted Education and Talent Development in the UI College of Education and by the UI and ISU colleges of engineering.

"Inventing and the invention process involves problem finding, reading, writing, researching, building, and speaking," according to Clar Baldus, Ph.D., Invent Iowa coordinator. "Teaching the invention process is a fun and creative way to integrate math, science, English, social studies and kinesthetic experiences in an unique way that can motivate at times even the most reluctant students."

Matthew's Sweep Stopper is currently being used in six grain bins on the family farm. The device allows Matthew, his dad, Glen, or brother, Randy, to safely finish sweeping grain out of the bin.

Farming is already among the most dangerous occupations. According to the National Safety Council, 700 agricultural workers are killed each year and another 120,000 incur disabling injuries. Such statistics drive home the point that all farm machinery, including grain sweepers, needs to be treated with respect.

"A sweeper is heavy enough and moves fast enough that it would be possible for it to take off a leg," Glen Christiansen, Matthew's father, said.

A sweeper spins around the bottom of a grain bin much like a second hand sweeps around a clock. Only in the case of the sweeper, the "hand" is an auger that makes it easier to transfer grain out of the bin. Although automated, the process always leaves some grain remaining at the bottom. To get rid of the remaining grain, someone must go into the bin and sweep it out. They must also keep an eye on the sweeper.

"It's kind of dangerous and that's how I came up with the idea for the Sweep Stopper," Matthew said. "We bolt it to the side of the bin and it stops the sweep. Then you can get out and shut it off."

The Sweep Stopper was one of several projects displayed at Invent Iowa this year that focused on assisting disabled people or providing safety, according to Baldus.

"Every year we have the mitten and boot drier projects. However, many of the young inventors focus on issues of safety. Several of students with farm backgrounds, like Matthew, completed projects specifically on farm safety," Baldus said.

Matthew has been working on a lot of projects since starting with Erector Sets as soon as he was old enough to wrangle a wrench. Later, his father, Glen, made space in the barn for a workbench, and Matthew has been putting things together ever since.

"I've always liked do engineering type of things," Matthew said. "I started on Erector Sets and then on scraps of metal dad had in the work shop and I'd just make something work out of it."

A good deal of his inventiveness has been channeled into an old lawnmower. His accomplishments, according to his mother, Cheryl, include a sprayer -- complete with wings -- for spraying weeds on the farm, and a lawnmower-sized field cultivator Matthew made by cannibalizing discarded cultivator pieces.

"It works very well," Cheryl said. "I remember watching his lights when he'd be out in the bean field."

With that background, coming up with a project for the Invent Iowa competition was a breeze for Matthew.

"This type of work is his thing," Cheryl said. "It's just natural for him to go out and come up with things. We've never had Game Boys or video games."

Matthew's first hurdle for the Sweep Stopper was deciding what material to use. He quickly discarded the idea of using wood or plastic before settling on the idea of quarter-inch sheet metal.

"We have a friend who has a machine shop in Scranton, so we just took a 12x12 inch piece of metal and he bent it at a right angle for me," Matthew said.

The angled piece of metal is then bolted to the side of the bin about six inches off the floor. When the sweep drops to a certain level, it hits the stopper. People inside the bin can then safely get out and turn off the sweep.

"The neighbors have been asking about it and they've been checking in here with me," Matthew said.

There has been enough interest shown by neighbors and other people that Matthew is already taking steps to market the device. He has a patent pending for his invention and has taken entrepreneurship classes at school.

It's that type of creativity that the scholarship was created to encourage, said Barry Butler, the UI College of Engineering dean, a professor of mechanical and industrial engineering and one of this year's judges at Invent Iowa.

"Our culture, educational system and laws on ownership of intellectual property combine to provide an environment where people are encouraged to use their imagination to invent," Butler said. "In the College of Engineering, we recognize our role in society to continually encourage and train young people to be tomorrow's contributors to technology. Supporting Invent Iowa is consistent with
our mission."

STORY SOURCE: University of Iowa News Services, 300 Plaza Centre One, Suite 371, Iowa City, Iowa 52242-2500.

MEDIA CONTACT: Larry Mendenhall, writer, 319-384-0019, Program: Clar Baldus, 319-335-6148,