Professional baseball is a grind, with daily games and countless hours of batting practice for hitters. But younger hitters working in a batting cage lack the feedback of seeing how that last hit would have traveled on the diamond. To help hitters get that experience, the company InMotion has developed the HitTrax system, capable of tracking batted ball speed, launch angle, and a number of other parameters that tell hitters how far each ball would have traveled during an actual game.
The system consists of separate hardware and software components. The hardware, encased in the rectangular white box seen above, consists of three near-infrared cameras and two near-infrared LED arrays that better illuminate the ball. Like other motion-capture systems, multiple cameras track the ball as it crosses the camera volume. The location of the ball in each camera’s field of vision, combined with the known distances between each camera, are combined to measure the position of the ball in three dimensions.
The box containing the cameras is positioned inside the cage, a few feet behind the batter and just in front of the plate, in a fixed position for both right- and left-handed batters. You typically wouldn’t want to stand by the box when someone is in the cage, of course, but the hardware is still well-protected from foul balls: the LED arrays are behind bulletproof glass, and the front of the box is “made from the same material as hockey boards,” according to Tom Stepsis, InMotion Systems’s director of marketing.
The tracking data is then fed into a physics engine to project the distance each hit would travel in the real world. But in addition to distance and trajectory, HitTrax also estimates whether each batted ball would result in a hit or an out. The fielders’ ability has been programmed to match the hitter’s, so high school hitters will face high school fielders, whereas more skilled fielders and deeper fences await older hitters.
InMotion, based in Northborough, Mass., claims that the speeds reported by the HitTrax system are accurate to within one mile per hour, as compared with conventional radar guns. Stepsis also claimed the distances reported were accurate to within five percent of the actual distance, as measured manually with a tape measure. The system does not track the ball’s spin (which has been shown to have an important impact on the distance a fly ball travels) but instead makes its calculation based on the first few feet of trajectory captured by the cameras.
The HitTrax software is controlled by a touchscreen, where the user can enter personal information, change settings, or switch between training and game mode. In training mode, the system can produce detailed spray charts, strike zone “hot and cold” zones, and trajectory data such as launch angle and exit velocity. Reports and leaderboards are available online so players can track their performance and get a sense of how a change to their swing mechanics might translate to in-game performance.
But game mode, Stepsis said, was entirely separate. Here, hitters can compete in home run derbies and on teams in simulated games. The system also includes fun features, like power boosts, to affect trajectories.
Despite its name, the HitTrax system is also capable of tracking pitchers. The system tracks the horizontal and vertical break of the ball, the “end speed” as the pitch crosses the plate, and where in the strike zone the pitch was located. Because the cameras are fixed in front of home plate, however, more in-depth statistics like release point, starting speed, and a more detailed trajectory of the ball’s path to home plate, are not available.
Prior to founding InMotion, the company’s founders had decades of experience with motion tracking technologies and a passion for baseball. It took InMotion “a solid two years” to develop the HitTrax system to the point where it was ready to be sold. Stepsis said that, because the product was so unlike other available offerings, the initial marketing focused on showing potential customers how to use the system.
“When we introduced this, part of the hurdle was explaining what it was to people,” Stepsis said. “And seeing is believing, so we did a lot of demos. And then once people saw it, word of mouth started to spread, and things really took off.”
The system is now in facilities across North America, along with some high schools, colleges, and the occasional private residence. For those in publicly-accessible facilities, the price for a session can vary widely.
“There are some places that charge over $100, there are some places that just put this in a coin-op [batting cage] and just charge double, so instead of $1 for 20 balls, it’s $2,” Stepsis said.
InMotion has gotten positive feedback from players, coaches, and facility owners as a training tool, but Stepsis said some users were also using it for tryouts or scouting purposes.
“Some of our customers who own facilities are also MLB scouts, and they love it,” Stepsis said. “They feel like the data we’re providing them just paints this elaborate picture of what the player’s like.”
As InMotion grows and HitTrax becomes more popular, Stepsis hopes that his company will be able to give players and coaches instant access to the type of data that will allow them to monitor their progress and quantify the effect of any changes in their swings.
“We’re not coaches. We just want to be data providers,” Stepsis said. “It’s all about making the indoor training environment more engaging and more beneficial.”