US Patent 7856290 Nesting negotiation for self-mobile devices

Disparate robotic devices can be automatically recharged and reprogrammed by self-scheduling individual time slots for the available recharging area(s) of a charging station. These charging stations provide a nest to which each robot must return periodically for power. These nests can also provide new tasking or patches for the robotic devices. The charging station and the robotic devices are both provided with communications capabilities and a protocol by which they can negotiate to find a time slot in which the device can be recharged, as well as determining a correct connector and a battery type.