GPS Units Get A Fix On The Football Priya Narasimhan, a football fan in Pittsburgh, wants to help referees make the right call. Her experiment: embed GPS units and accelerometers into football equipment to keep track of where the ball is and who has possession of it.
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GPS Units Get A Fix On The Football

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GPS Units Get A Fix On The Football

GPS Units Get A Fix On The Football

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Say you're watching Brigham Young take on Arizona tonight in the Las Vegas Bowl, and a receiver stretches to catch a pass at the goal line. At the same time, a defender smacks the ball out of his hands and out of bounds. So, is it a catch? Is it a touchdown? Is it a fumble? Referees turn to the instant replay. But what if the football could tell you what happened? It's "Science Out of the Box."

(Soundbite of music)

SEABROOK: Priya Narasimhan teaches at Carnegie Mellon University in Pittsburgh. Her specialty - embedded real-time systems. She and her students have planted a GPS inside a football, and they're working on special gloves that could determine whether a ball was caught or fumbled. Priya Narasimhan joins us now from member station WDUQ in Pittsburgh. Go Steelers!

Dr. PRIYA NARASIMHAN (Associate Professor, Electrical & Computer Engineering Department, Carnegie Mellon University): Go Steelers!

(Soundbite of laughter)

SEABROOK: So how did you come up with this idea?

Dr. NARASIMHAN: When I first moved to Pittsburgh in 2001, I caught the football bug here, and I've never looked back since. I throw things at the TV when a call doesn't go my way, and it was really inspired by doing that and recognizing that if you did have ways to track various things on the football field, it would be a really interesting concept to try and supplement today's refereeing with additional electronics that you might put in the football, in the uniforms, in gloves, and other things.

SEABROOK: So what exactly do you put inside the football, for example?

Dr. NARASIMHAN: So, inside the football, we've done a couple of things. We've put a mini GPS unit inside the football, and the GPS unit then allows us to track the football as it moves around the field of play. So, for example, if there's a quarterback who throws the football, then we can track the trajectory of the football as it's moving in the field of play. And we're trying to improve this all the time, because obviously we'd like to get this to a finer-grained resolution so we can actually get it down to inch level.

SEABROOK: How is the resolution right now?

Dr. NARASIMHAN: We're at about 30 feet, which as you can imagine is very far from doing, you know, 14 inches versus a first down.


Dr. NARASIMHAN: And this is the very first prototype of it.

SEABROOK: You know, it occurs to me that when someone throws a football, it kind of goes in a spiral motion through the air. Does that mess with the GPS?

Dr. NARASIMHAN: Absolutely. Absolutely it does. And so, what happens to the GPS unit is it's latching on to satellites in the sky. So as you can imagine, the ball is spinning around. And if you have a GPS unit inside, one minute it finds the signal, the next minute it doesn't. So it's cutting in and out of the signal. So additional things we've done is put base stations which transmit wireless RF signals around the football field, so the ball is continuously in contact with something. Even if it's not GPS, it's in contact with something else that is relaying its coordinates or its position on the field of play.

SEABROOK: So I understand there's also a pair of gloves. What do they do?

Dr. NARASIMHAN: So, the gloves are standard-issue wide receiver gloves. They have a set of pressure sensors on every one of the fingers, and they're sewn into the gloves. And whenever the player makes contact with any object, the pressure sensors will fire telling you exactly how much pressure was applied when that object came into contact. So, for example, someone who's catching the football, we can tell you how that person caught the football, whether they caught it, all of those different things.

SEABROOK: Could it revolutionize the instant replay?

Dr. NARASIMHAN: That's one of the hopes. I mean, I don't think this will ever replace human referees because human referees can make very interesting decisions based on their vast experience, based on having seen the same play at multiple different games. But this thing could supplement their decision-making especially if, you know, for example a coach throws the red flag on a field and you have to go to instant replay or you have to go back and, you know, re-decide the call that you just made. I think this could supplement their decision-making.

SEABROOK: It makes me wonder if there are other things you could do with this technology like track the hands of a surgeon or something.

Dr. NARASIMHAN: We've actually done something similar for the deaf. We took another variant of these gloves. We had sensors again embedded on all the fingertips, so somebody who's deaf and signs using American Sign Language, we can capture all their gestures because we can tell you how much each finger was bent, what the relative distance between hands are, etcetera. We capture those gestures. We relay them to a phone using Bluetooth. And then the phone speaks the word out aloud. So somebody who's deaf and speaks in American Sign Language can talk to somebody who doesn't know American Sign Language.

SEABROOK: On the phone?

Dr. NARASIMHAN: Using the phone as the medium for actually voicing whatever you were gesturing.

SEABROOK: Wow. Priya Narasimhan. She's a professor at Carnegie Mellon University in Pittsburgh. Thanks so much for talking to us today.

Dr. NARASIMHAN: Thank you so much for having me.

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