Patent ID: 7332890

Claim:
A method for energy management in a robotic device, the method comprising the steps of: providing a robotic device comprising at least one energy storage unit and a signal detector; providing a base station for mating with the robotic device, the base station emitting a homing signal; determining whether a quantity of energy stored in the energy storage unit is below one or both of a predetermined high energy level and a predetermined low energy level that is lower than predetermined high energy level; performing, by the robotic device, a predetermined task based at least in part on whether the quantity of energy stored is below the predetermined high energy level or the predetermined low energy level; the predetermined task comprising: cleaning without seeking the homing signal when the quantity of energy is not below the high energy level; cleaning while seeking the homing signal when the quantity of energy is below the high energy level; seeking the homing signal without cleaning when the quantity of energy is below the low energy level; and following the homing signal to return to the recharging base station when detecting the homing signal during seeking the homing signal.