Are the Fancy New Curling Brooms Fair? Robots and Lasers Will Help Figure It Out

So-called “Frankenbrooms” are causing tension amongst the world’s curlers

Vanoc/Covan via Flickr

For the last few years, the world of curling has been thrown into turmoil over a broom. While this might seem like a small thing to non-curlers, the scandal has rocked the sport. Now, scientists are using lasers and robots in a bid to restore fairness.

On the surface, curling seems like a pretty simple sport, if a bit quirky. Like a version of shuffleboard played on an ice skating rink, curling involves teams competing to see who can get a heavy granite stone closest to the center of a giant bullseye. A pair of players armed with brooms try to control the stone’s speed and direction by sweeping the ice in front of the sliding rock. The brooms reduce friction and clear any debris that could mess up the throw.

For centuries, these brooms were made with natural fibers, but in recent years artificial fibers have crept onto the ice, Donna Spencer reports for the Canadian Broadcasting Corporation.

“The last couple of years we’ve had a revolution in the sport,” Ben Hebert, a two-time world champion and Olympic gold medalist curler tells Martin Smith for Motherboard. “Manufacturers have come up with some products that let you do some fancy stuff to the rocks.”

At the core of the heated, years-long debate is the so-called “Frankenbroom.” Made with artificial materials, the Frankenbroom’s brush fibers were smooth on one side and rough on the other and often paired with hard inserts.

This combination allowed sweepers to put more downward pressure, creating grooves in the ice for the stones to slide along, giving them greater control over the stone’s direction, Smith reports. This changed the game so dramatically that 50 top teams refused to use the brooms, and officials banned them.

Since then, curlers have questioned whether other broom heads should be made illegal, Smith writes. "A new hair brush has the exact same impact," Olympic gold medalist Brad Gushue told Spencer. "It shouldn't be in play. We have too much control over the rock with those brooms."

The argument over which broom heads were fair to has grown so heated, the World Curling Federation teamed up with scientists from the National Research Council of Canada (NRC) to put the brooms to the test, Smith writes.

The scientists pulled out all the stops to measure how the many different broom heads affected the ice and the stone, including a robot designed to throw the stone the same way each time and sensors mounted on the broom heads to measure pressure and speed of sweeping. Additional sensors on the stone measured its speed, spin, temperature, acceleration and rotation, while laser scanners built detailed pictures of the ice’s surface during the trials, Smith writes.

For three days, the scientists took measurements and scans of nearly every imaginable variable to compile enough evidence to determine the best ways to bring fairness back to the sport in time for the 2018 Winter Olympics. 

“We don’t want it to be about the fabric on your broom head,” champion curler Emma Miskew tells Smith. “We want it to be about throwing it [the rock] well.”

The curling world now waits with baited breath to see where the sliding stone falls.

Editor's Note 6/1/2016: This article has been updated to show the international effect that the new brooms have had on the sport. An additional correction was made in the reference to the World Curling Federation headquarters, which was previously noted to be located in Canada. 

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