Teardown – Gearbox

After quite a bit of prying, we finally separate the two halves of the box. We can see some surprisingly heavy-duty hardware in here.

This metal, multiple interlocking gearbox is heftier than the standard brass or plastic gearbox you see on most consumer products. And judging by the gear ratio, this thing is built to generate a lot of torque.

With the cover off, we can see there’s a threaded part at the end of the winding spindle that passes through an optical gate, letting the shoe know if it’s tightened (or loosened) too far.

This unit outputs an impressive amount of pull force for its size, easily in the neighborhood of 30+ lb. before stalling out. You don’t often see a box that fits in the palm of your hand and can lift three gallon jugs of milk, with power to spare. The gearbox helps by stepping down the RPM while increasing the torque, but how fast must the motor be spinning? We recorded an audio clip of the motor running and ran it through Audacity’s Fast Fourier Transform (FFT).

We think the 600Hz is the motor with the other spikes being harmonics or brush noise. This would correspond to approximately 36,000rpm.

That’s very impressive!

Though not waterproof, the polycarbonate case is built to take a beating. There are screws to hold it together around the gearbox and motor, ribs everywhere, and it is made out of plastic that’s known for its resistance to impact.

Flip the battery up, and we find out it’s a 630mAh LiPo, about three times larger than the Apple Watch battery.

The Electronics Board

The main board packs an impressive amount of electronics. Its heart is an ARM Cortex M4 main processor that controls the entire mechanism as well as various other peripherals. The smarts for the wireless charging are also found in here. The HyperAdapts use a protocol called Qi, which is becoming more commonplace in smartphones like the Nexus 5 and 6 and Galaxy S6 and S7. A driver chip for the motor is also used to detect the increase in current draw when the laces have been done up too! Pretty smart!

A few details that the more tech-savvy hardware enthusiasts may be interested in:

The wireless power receiver is a Qi-compatible wireless charging IC, a standard that is being seen more and more in consumer devices.

The motor driver is a very elegant solution for driving DC motors with all sorts of special features and protection, especially useful to make sure your shoes don’t catch fire!

The main processor is from Atmel (now Microchip), which packs what seems to be an overkill ARM Cortex M4 processor. However, it is specified for very low power operation. Maybe this hints to future features being added in with this set of hardware?

LED board

There is a separate little board, connected at right-angle to the main one, which is responsible for the cool blue glow coming from the side of the shoes. This board houses a huge array of tiny little lights.

Interestingly, Nike chose to use an array of 32 top-emitting and 14 side-emitting RGB LEDs here. At first, this seems excessive to light up such a small area, but all those LEDs provide a uniform brightness across the side of the shoe, where one or two large LEDs would have created bright spots.

Also the board that they are mounted on has some mysterious burn marks on it, where it looks like it might have been depanelized with a laser. (Depanelization is the process of separating one large board into lots of smaller ones. This is usually done at the end of the manufacturing process, so you don’t have to handle a bunch of small boards individually).

Heel LED flex

This flexible circuit has some more electronics wizardry in it by being able to drive 15 tiny lights from only 4 wires. They use a clever controller from Texas Instruments to achieve this.

Some very careful design and manufacturing must have been used here to ensure the components were not subject to unnecessary stress which could easily break electronics and their housing while being made.