Scavenger Technology Allows Robots to “Eat” Metal for Energy

When electronics need their own power sources, there are two basic options: batteries and harvesters. Batteries store energy internally but are therefore heavy and have a limited supply. Harvesters, such as solar panels, collect energy from their environments. This gets around some of the downsides of batteries but introduces new ones — they can only operate in certain conditions and can’t turn that energy into useful power very quickly.