The flex PCB is small, but carries lots of windings [Moritz] used ... To drive the coils, he used a pair of TB6612FNG stepper motor drivers, controlled by a Wemos D1 Mini. The housing was 3D ...

It’s a small linear motor which [ligonapProduktion ... the break shows him testing the motor. In this screenshot he’s holding the center shaft while the coil assembly moves back and forth.