If we don't think too complicated - I've got an idea, but I don't know if that works. Here's a sketch of what I thought (sorry for the crude one, haven't been sketching a long time):
The elastic white bands are held in channels which have on each end holes for nylons straps, all connected to a main strap, which is activated by the thin pressure sensor under the heel. A ultra strong micro-motor starts winding up the the main strap and tightens the elastic bands. A clamp would secure the strap when the motor stops. For unlacing the shoe, you press the release pressure sensor behind the light sheet with the Nike logo. A control chip supervises the motor, clamp, release, photo-diode for the night sole and side LEDs light-up. That's what came into my mind for power laces - not complicated, but maybe working (minus the sound effects

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