KinaTrax Gives Rays In-Game Markerless Motion Capture Data

In an effort to keep their pitchers healthy, the Tampa Bay Rays have enlisted the services of markerless motion capture company KinaTrax. As Jeff Passan of Yahoo! Sports reported Monday, the Rays are the first team to partner with the Philadelphia-based company.

When asked about the technology Tuesday, KinaTrax founder Michael Eckstein was reluctant to reveal much of the technology that drove his company’s system. Images from “multiple cameras” positioned throughout the ballpark (an earlier test used eight) are stitched together to create an unobstructed, 360-degree view of the pitcher. Eckstein compared his system to the commercially-available Microsoft Kinect, which uses infrared and sonar tracking to capture a user’s position for video gaming or other applications.

“The Kinect has a focal length of 8 to 14 feet, and captures 30 frames per second,” Eckstein said. “The challenge is, how do you scale that up to an MLB stadium, where you have to capture 275 to 300 frames per second from 350 feet away?”

Once the data is collected and uploaded to cloud storage, “proprietary algorithms” are then used to identify the position of body landmarks like joints and calculate the distances, angles, velocities, and accelerations between the various body segments. In an earlier talk at the 2013 SABR Conference in Philadelphia, Eckstein claimed that the positions measured by the system were accurate to within 1.5 centimeters.

It is probably no surprise that capturing such detailed visual information hundreds of times per second is a costly process. Eckstein estimates that a typical game could produce up to 1.4 terabytes of data. The data is owned by the teams — since it identifies each pitcher and is thus considered medical information, even KinaTrax can’t access it without permission once it’s collected. For teams unable to work with the raw data, KinaTrax can also develop reports on key metrics; Eckstein said in his 2013 presentation his system was capable of generating these reports overnight.

“Some teams have the ability and the staff to say, ‘We want these kinds of reports, and these kinds of analytics,’ and then we can go out and produce them,” Eckstein said. “And then if teams have very qualified staff, they’ll get the raw data to work with themselves.”

Although KinaTrax worked with the Mets in 2013 to develop their system, Tampa Bay is the first major-league team to install the system and collect game data. And while it’s too early to draw any conclusions from the data collected by the system, Eckstein is happy with KinaTrax’s early performance.

“We’ve successfully recorded thousands of pitches, and the system is working as expected,” he said.

According to Eckstein, KinaTrax had discussed possible arrangements with 17 MLB teams between the Winter Meetings, Cactus League, and Grapefruit League before finally coming to an agreement with the Rays. Eckstein was excited about working with the Rays, praising their front office acumen and even the symmetrical shape of Tropicana Field (which made camera installation easier).

“The Rays are among those top major-league teams that understand what we’re doing and have an understanding of big data,” Eckstein said. “We couldn’t ask for a better team for our pilot.”

Teams have already proposed a number of different uses for the system. For major league pitchers, teams could use the system to demonstrate “best practices,” and highlight the subtle changes in mechanics that could separate a great outing from a poor one. But Eckstein also discussed the possibility of installing the cameras in minor-league parks, allowing teams to better teach proper mechanics to young arms while also developing “longitudinal patient records” of changes to a pitcher’s kinematics over time.

“All of the teams we’re speaking to want them in their major league stadiums,” Eckstein said. “But the really innovative teams tell me, ‘Where we will get the most benefit out of this is with our Single-A or Double-A teams.'”

Once installed, the system can also be adjusted to capture mechanics in bullpen sessions, and could be modified to track hitters’ swing mechanics. For now, though, KinaTrax is primarily focused on the action on the pitcher’s mound.

“There’s a consensus among teams about this anecdotal evidence of pitchers who are great in their bullpens but then lose it on the mound,” Eckstein said. “But truth be told, it’s the in-game information that managers, coaches, and scouts are after.”

Before founding KinaTrax, Eckstein worked in the technology sector for 25 years, helping companies figure out how to use technology to develop competitive advantages. A baseball fan, Eckstein found himself at a lunch with a Phillies senior executive in 2012, and the conversation turned to Roy Halladay’s early-season struggles.

“He said, ‘Wouldn’t it be great if we had a way to measure his mechanics and see what he’s doing wrong?'” Eckstein said. “And I said, ‘Oh, this will be easy. We’ll go to Microsoft and they’ll come up with something.'”

It wasn’t that easy, of course. The leap from the existing technology to in-game motion capture from hundreds of feet away required the development of an entirely new technology platform, which became the basis for KinaTrax.

Before Monday, KinaTrax first announced itself at the 2013 SABR Conference in Philadelphia, where Eckstein gave a talk and brief demonstration on his system. At the time, KinaTrax had persuaded the Mets to let them test their camera system in Citi Field. The eight-camera test was successful, but no actual game data were recorded.

Now that the word is out on KinaTrax, Eckstein plans to return to the Winter Meetings and put his newly-tested product before the decision-makers in MLB front offices.

“We’re going to have serious discussions with teams about agreements for the 2016 season,” he said.

But go on the company’s website and you’re greeted not by a picture of a Major Leaguer or of Tropicana Field but by a youth baseball pitcher. This is not just a nice image: Eckstein said KinaTrax is planning to scale its system down for college, high school, and even youth-level teams.

“Clearly the arm motion is very different for an eight or 12-year-old versus a major league pitcher,” Eckstein said. “But we feel that with the nuggets we’ve learned, and with cameras that don’t have to capture 275 to 300 frames per second and don’t have to be 350 feet away, we can bring the price of the system down to that level.”

We hoped you liked reading KinaTrax Gives Rays In-Game Markerless Motion Capture Data by Bryan Cole!

Please support FanGraphs by becoming a member. We publish thousands of articles a year, host multiple podcasts, and have an ever growing database of baseball stats.

FanGraphs does not have a paywall. With your membership, we can continue to offer the content you've come to rely on and add to our unique baseball coverage.

Support FanGraphs




Bryan Cole is a contributor to TechGraphs and a featured writer at Beyond the Box Score. You can follow him on Twitter at @Doctor_Bryan.

Comments are closed.