Last updated at 13:38

Smart shoe devices generate power from walking

Smart shoeOther

Imagine being able to generate electricity, just by walking along.

German scientists have made two energy-collecting devices tiny enough to put in the soles of shoes.

One device collects energy when your heel hits the floor, while the second works as the foot is swinging; so every step you take generates power.

Smart shoeOther
The shock harvester fits inside the sole of a trainer

At the moment they can only generate a very small amount of power: enough for tiny gadgets. Hundreds of times more would be needed to charge a smartphone.

Running shoeOther
The devices use the motion between magnets and coils to generate power

The people behind the tech hope to be able to use the devices to create shoes that tie their own laces, to help older people who find tying shoelaces difficult.

The invention was published in the journal Smart Materials and Structures.