CEDAR FALLS — Effectively programming a Lego Mindstorms robot and efficiently operating it in 2-1/2 minute matches can be challenging.

But a team of Hansen Elementary School sixth-graders did it — and came up with a solution to provide clean drinking water in developing countries.

Speedsters, which includes five students, won the FIRST Lego League champions award and the robot performance award at both the regional and state competitions. Now the group is preparing for the FIRST World Championship in Detroit April 25 to 28, one of two Iowa Lego League teams advancing to the event. FIRST — or For Inspiration and Recognition of Science and Technology — is an international organization that sponsors Lego League and a number of other robotics programs.

This is the third year since the team was formed and second year with its current members. But it has taken time to consistently do so well in both robotics matches and making presentations to judges.

When the team began, it had nine members and “did really, really horrid,” said student Param Sampat. Five kids didn’t continue with the team the next year and another joined, completing the group that now makes up Speedsters. Sampat noted they advanced it to the state meet last year, but it wasn’t until this year the team really thrived.

“Our robot did extremely well,” said student Natalie Olsen, at the state competition in January. While typical teams scored in the range of 100 to 150 for their robot missions, “we got 195.”

Teams work on a challenge to solve real-world problems related to a theme, which is “Hydro Dynamics” this year. Scores on the robotic portion of the challenge are determined by how many missions are completed in the 2-1/2 minute tabletop matches using the robots. Four adult coaches and mentors — all parents of the children — provide guidance for the team.

Parag Sampat, one of the coaches, said the kids didn’t work well together the first year. He started volunteering with the goal of helping them become a cohesive team.

“We work in a coordinated fashion,” he noted. “I know without being a team you can’t accomplish anything. As the years go by, they respect each other, they work as a team.”

Students work in pairs on the robotic missions during matches. When one group finishes another steps up to add different attachments and restart the robot. Speed is important so they can earn as many points as possible.

“They practice just like a relay,” said Parag Sampat. “They keep practicing the transitions.”

Lego League teams also complete a project related to the theme that involves identifying a problem and developing a solution. That led them to create a device to purify water using ultraviolet light. Exposing bacteria or other germs to UV light kills them.

“We came up with this idea because people in impoverished homes don’t have access to clean drinking water,” said student Varun Gulwadi.

He noted those in developing countries without indoor plumbing often store up water. A common storage method uses earthen clay pots with steel lids, Gulwadi explained, “but microbes and other bacteria can get into the water.”

So the team’s prototype water purifier is built into a lid that can be put on such pots. “We wanted to incorporate the current way they store water,” said Gulwadi.

A test tube containing a light extends from the bottom of the lid. On top, the students created a crank mechanism connected to a dynamo, or coiled copper wire.

Student Pranav Kota explained that a dynamo “changes the magnetic field and creates electricity.” That powers the bulb, which in this case is an LED light.

The crank mechanism uses part of a hanger, a tape roll with a CD glued to the top and the bottom, and the motor from a toy windmill.

“We made this all out of materials you can find at home,” said Param Sampat. “The thing is to get the UV light to turn on. We’re working with the (University of Northern Iowa) departments of physics and biology to test a real UV light so it works.”

He added, “We feel that there’s really no point in having a good project without putting it in use. You have to get a goal in mind. You need something on a bigger level.”

If the students can get their idea into a workable format, they are thinking about marketing, as well.

“Our plan is to make kits that you would build by yourself,” said student Henry Wiering, so it’s as inexpensive as possible. In addition, there would be a pre-built model of the purifier.

Parag Sampat said the students also are contacting nongovernmental organizations to gauge interest in the water purifier.