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Glowing Hockey Puck

February 12, 2002

A public radio commentary

Last night at a dinner party someone leaned over and said to me "How exactly do they make the hockey puck glow?" I thought they were drunk, but I found out that indeed on TV there's a hockey puck that glows blue, until it's slapped to over seventy miles an hour when it turns red and develops a long red tail. Intrigued, I looked into this and found it's a real tour de force to make a hockey puck glow.

Rick Cavallaro, who headed the team, described the problem as this: We had "to track and highlight a frozen hockey puck traveling at times in excess of 100 mph after being walloped by angry 250-pound men with sticks."

In developing the puck, the team's first lesson was that the laboratory isn't the same as the real world. In their labs they crammed a puck full of electronics, then gave it to a real-world player. He found the puck too light. Rick and his team learned a puck even an ounce light can change the game completely.

So, they got official hockey pucks, cut them in two, carved out the middles and loaded their batteries and transmitters. Putting them back together was their next major problem.

They searched to find a glue of just the the right weight and adhesivness. They felt it pretty important the pucks not split apart and spew batteries on a slap shot. To test the various glues they hit pucks with sledge hammers, squeezed then in vises, and then shot them out of cannons at 105 miles per hour.

Then the real world intervened again. They didn't realize that the pucks are stored on ice for several hours before being put into play. The problem is that batteries lose their charge at low temperatures. Since in a hockey game up to thirty pucks might be used, they couldn't just turn them all on because when frozen the batteries wouldn't last long.

They put in a sensor so that when the referee drops it the shock turns the puck on. It goes off if it isn't hit for 45 seconds - which, of course, never happens in a game - but if the puck goes into the stands it turns off, and the new puck put into play by the ref will take over.

During the game the puck's electronics sends back it's position every few seconds to twelve computers housed in a forty-foot semi. They process all the data then draw the puck on the TV screen.

This new glowing puck upset hard core hockey fans, who claimed they could already follow it. But since it helped attract new viewers, I have bad news for devoted sports fans. The team that brought us the glowing hockey puck is adapting their technology to other sports. They want, for example, NASCAR coverage to feature cars that glow.

Copyright 2002 William S. Hammack Enterprises