Electric engineer build’s Thor’s weapon, Mjolnir which can only be lifted by him
A replica of Thor’s hammer Mjolnir build by an electric engineer using powerful electromagnets and a fingerprint scanner
Only the ones who are worthy can hold and use Thor’s famous and legendary hammer Mjolnir in Marvel comics. For the ones who are not worthy, which is almost everyone except Thor and the odd someone else occasionally (an useful loophole for writers), Mjolnir just cannot be lifted off the ground.
It is this thing that electrical engineer Allen Pan, AKA Sufficiently Advanced on YouTube, made a decision to reproduce in his very own take on a “working” Mjolnir.
He decided to use the strong magnets to make the hammer immoveable, as that was the best method. He filled a microwave oven transformer electromagnet that uses electricity to produce a magnetic field inside the head of his Mjolnir. This in turn produces a strong magnetic pull, which is so strong that when the hammer is put on a metal surface, it feels very heavy to lift.
The handle is attached to a capacitive touch sensor, which in turn is attached to an Arduino Pro Mini and a solid state relay, which works as a switching device. The electromagnets switches on immediately when someone grasps the handle, attaching the hammer to the metal surface.
However, a fingerprint sensor that is keyed to Pan’s thumbprint can be used to turn off the hammer. But the magnets switches on when Pan holds the hammer. Then it switches off again when he moves his thumb over the sensor, letting Pan to lift the hammer.