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Break it down: A soccer ball with serious game

From CNET Magazine: We crack open the MiCoach Smart Ball for a look at how Adidas gave this soccer ball a brain.

Bill Detwiler
3 min read

The Adidas MiCoach Smart Ball won't instantly turn you into Cristiano Ronaldo or David Beckham. But this brainy training ball is packed with tech to help soccer enthusiasts play better. Combined with the free MiCoach Smart Ball app, it gives players real-time feedback on the strike point, spin, speed and flight path for practice kicks. Using that data, players can perfect long passes, increase shot power and even add more bend to free kicks.

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Tyler Lizenby/CNET

To make a soccer ball smart, Adidas added a 16-bit RISC microcontroller, a multi-axis MEMS eCompass module and a Bluetooth connectivity module, all powered by a 3.7V lithium ion battery and inductive charging system. Everything is packed into a standard size 5 (22cm diameter) soccer ball that weighs 445 grams (well within range for a FIFA-approved ball).

Cracking open the Adidas MiCoach Smart Ball

Whenever I crack open a gadget, I aim to do so in a way that lets me reassemble it after my teardown is complete. Unfortunately, there was no practical way to get inside the MiCoach Smart Ball without cutting it open. At least all the destruction was for a good cause.

Tyler Lizenby/CNET

Using a very sharp knife, I carefully cut through the outer shell, inner lining and bladder of the ball. I started my incision about an inch above the lightning bolt logo and removed a roughly 7-inch section. I carefully avoided cutting myself or the receiver coil for the inductive charging system, which I knew was located behind the lightning bolt graphic on the bottom of the ball.

Once I crafted an opening large enough, I could see how Adidas gave this ball its brain. Sitting in the center of the inner cavity is a small, white plastic sphere held in place by heavy-duty rubber bands attached to the ball's inner layers. A single wire connects the circuits inside the orb to the receiver coil, which is attached to the inside of the bladder.

Tyler Lizenby/CNET

After unhooking the rubber bands and prying loose the receiver coil, I was finally able to remove the MiCoach Smart Ball's electronics package. Both physical snaps and glue hold the two halves of the package's hard plastic shell together. I had to cut through the shell to access the circuit board and battery inside, but both came out of the opened shell without much fuss. The whole teardown process took about 30 minutes.

What the teardown tells us

Tyler Lizenby/CNET

  • A well-made ball: I'm not an expert on soccer ball construction, but every hands-on review of the MiCoach Smart Ball I've watched or read gave it high marks for quality. The slightly textured PU (polyurethane) cover is made of 32 thermally bonded panels. The inner air bladder is made of butyl.
  • The ball within a ball: The brain of the MiCoach ball is a second 1.5-inch diameter sphere suspended directly in the center of the ball. Inside sits a single circuit board and battery. Soldered to the board are a Texas Instruments 16-bit RISC microcontroller that can operate at a clock speed of 25MHz and has 128KB of non-volatile memory and 10KB of SRAM. The sensor that collects all the kick data is a multi-axis MEMS eCompass module (3D accelerometer and 3D magnetometer) from STMicroelectronics, and a Nordic Semiconductor Bluetooth chip connects the ball to your mobile device.
  • Brain surgery isn't practical: I couldn't remove or replace the entire processor, sensor, battery and charging assembly without cutting the ball open and damaging the rubber bands that hold it in place. And while it is possible to patch leaks in some soccer balls, the construction of the MiCoach ball's cover and bladder, along with the size of the hole needed to remove the assembly, makes replacing internal hardware impractical.

Pricey but a unique training tool for the soccer enthusiast

The MiCoach Smart Ball costs $200, which is pricey for a practice ball. But considering that a premium match ball, such as the Adidas Brazuca, costs anywhere from $100 to $160, paying an extra $40 for a ball with brains isn't such a huge leap.

This story appears in the summer edition of CNET Magazine. For other magazine stories, go here.

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