Using an activity tracker to arbitrarily count your steps can be very hit or miss in its usefulness. It makes more sense to get one designed to track a specific activity in order to get the most insight out of the data.
For tennis players, Smash is a new wrist band meant to help improve their game through data. The device includes an accelerometer, gyroscope, and magnetometer, able to collect data 250 times per second. This allows for really precise measurements which, combined with open API access, might help it find a wider audience with third party developers.
The goal with opening up an API as a stretch goal in the Kickstarter campaign is to expand into other sports and beyond. It's been obvious for awhile most niche products need help from a community of interested developers.
"We’d love to move Smash into more sports, however we can’t do them all at once," says Smash Wearables founder Rob Crowder. "We’ve had some great feedback and requests ranging from baseball to badminton, table tennis to Padel—which is huge in Spain. To do them justice we’d need to spend significant time on algorithms and an experience that makes sense," Crowder continues. "So, for devs we’d love to offer a simple toolkit so they can collect measurements for whatever sport they’re passionate about. This is what we’re working on as a stretch goal."
But having a wrist band that that can track really precise movements could also be used outside of sports. Crowder says he’s also heard feedback about Smash being used for things like physiotherapy and rehabilitation.
"Not from sports injuries necessarily, but people requiring [physiotherapy] due to surgery or other injury," he says. "Recovery time could be shortened if they were able to repeat the correct movements more often."
As for the actual device, all data processing happens inside the hardware unit itself and then the results passed to an app on a phone. This means that even while Smash is generating peak data, it doesn’t require one of the latest smartphones to capture the information. The data processing onboard the device does affect battery life, but right now in its initial phase Smash gets around 6 to 8 hours.
The wrist band collecting so much data also brings up the issue of separating the noise from the signal. This has been a constant area of focus for Crowder from the beginning. He says that recognizing a person hitting the tennis ball is easy, it’s everything beyond that which is tough.
"The clever bit is recognizing events within a shot that demonstrate good technique," says Crowder. "This is where the majority of time has been spent, writing algorithms which identify technique markers within a stroke. Taking the forehand as an example it’s about dropping the wrist at the back of the backswing, driving forward and upwards with the right angle of wrist through contact and finishing with a nice high follow through to ensure decent topspin. Each stroke currently has between six to twelve events."
As more devices include tracking sensors, effectively measuring data from wearables will become more important. If device manufactures support open APIs, it can help make devices say for tennis, attractive even to people who don’t care for the sport.
Zepp is another example of this type of gadget not being saddled to one sport. The quarter sized device can attach things like a gold club, tennis racquet, and baseball bat. Zepp has the same goal, which is to get players immediate feedback on their technique.
It’s still early for Smash, but with over 250 backers and quickly approaching a quarter of the funds, there’s a good chance third party developers will be able to get this tracker into their hands.