Monthly Archives: July 2013

Cheetahs hunting: a coda on sensors

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I really need to keep up with my back issues of Wired.  After posting about the possible use of portable sensors in sports to monitor defense and skills, I came across this feature  in Wired about different kinds of sensors, including one made by X2 Biosystems to measure head impacts.  This system uses a small, adhesive sensor, placed behind the athlete’s ear, to monitor the force of head impacts in real time.  This provides additional data that coaches and medical staff on the sideline can use in judging whether a player should be allowed back on the field or not after a blow to the head.

I’m curious how sensitive these sensors are and whether they could or do record less extreme events like rapid acceleration and deceleration while players run on the field.  The nice thing about the X2 system is that information is collected in an application that allows collation of health care provider information and clinical results as well, keeping data in one place.   I’m also curious if the general, anonymized data will be made publicly available.  According to the Wired article, a number of collegiate and amateur sports organizations are gathering data as part of a central initiative, presumably to monitor and prevent concussions.  It would be interesting to see if other things could be studied from that data.

Cheetahs hunting redux: the next step in measuring baseball defense?

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I had another thought about the collars that were used to measure cheetah hunting behaviors.  For a summary that is not behind a paywall, see here.  How long will it be before tools like these are used to measure baseball players, playing defense on the field?  Tools like FIELDf/x quantify the behavior of baseball players from an external viewpoint.  Sportvision’s cameras record elements of the game like positioning, how quickly a defender moves, the kind of jumps he takes when getting to (or missing) the ball, and overall range.  This allows a much clearer view of defender territory, ability to reach difficult balls, and general quality.

Now, what if that were combined with the kinds of tools that were used to measure cheetahs?  As the authors of the article point out, the collars they designed could record “some of the highest measured values for lateral and forward acceleration, deceleration and body-mass-specific power for any terrestrial mammal.”  If it can do that for cheetahs, it can certainly do that for Brendan Ryan and Mike Trout, much less Derek Jeter or Raul Ibanez.  By the way, this would obviously not be implemented as a collar.  You don’t have to drug and tag shortstops.  At least not for these purposes.

Instead, these monitoring devices would be attached to the body, and possibly in multiple places, to capture kinesthetics.  Now, one might say, can’t all this data just be captured by  image capture from the Sportvision feed, and algorithmically extracting things like acceleration, body positioning, etc?  Quite possibly; I don’t know enough about that technology.  But what about actions taken on fields which are not equipped with Sportvision cameras, which is to say, most of them?

That might end up being the sweet spot for implementing this technology, as an adjunct to training, coaching and scouting.  Being able to measure how quickly a high school shortstop actually reacts to the batted ball, based on his lateral acceleration and ability to accelerate/decelerate would provide a more proximal measure of athleticism when making scouting evaluations.  It can also allow quantification of both areas for improvement, as well as a measure of improvement during coaching.  And using these kinds of monitors can also help answer questions on what really is important for defense, based on a comparison of proximal, immediately measured body motions and more distal metrics such as are measured by things like UZR.

Like any of these kinds of quantified self tools, though, it remains to be seen how useful this extra data will be.  However, for the savvy organization at any level, I think these kinds of tools are worth thinking about.