By now your social media feeds have been swarmed by Michael J. Fox demonstrating the functions of the 2015 Nike Mags power lacing system, as seen in back to the future. If you haven't you can check it out here
Thanks to Forbes we are able to see a breakdown of all the mechanics that went into designing, creating, and manufacturing the self lacing sneaker. The automatic lacing system consists of two separate parts around the foot and ankle areas. In the lower part, the self lacing system has a strap moving mechanism located in the sole of the sneaker. A small motor powers the mechanism by rotating the device's driveshaft with two gears; the gets transfer power to two belts attached to the laces. The ankle cinching system in the sneaker's upper uses a different mechanism that lies behind your achilles tendon. It uses a coil spring wrapped around a shaft that basically pulls on the ankle strap. The belt stays tight thanks to a locking mechanism, which is disengaged by the sneaker's control system.
To simply put it, the two mechanism located in the upper and lower part of the sneaker work together and are triggered after your body mass is detected by a weight sensor in the heel. For adjustments, there are manual controls. Push the green button to tighten the straps and a red button to loosen them. It's super easy!