An electrical charging system for charging an autonomous robot, comprising: - an autonomous robot powered by a re-chargeable battery and having a first charging member; and - a charging station, including: - a second charging member configured to receive the first charging member on the autonomous robot when the autonomous robot is docked with the charging station for charging the rechargeable battery; - a power supply configured to charge the re-chargeable battery of the autonomous robot when docked at the charging station; - a sensor configured to measure an amount of charge transferred from the power supply to the autonomous robot during charging; - a processor, in communication with the sensor, configured to determine, from the amount of charge transferred from the power supply to the autonomous robot measured by the sensor, a state of charge of the autonomous robot; and - a communications device, in communication with the processor, configured to transmit to the autonomous robot the state of charge of the autonomous robot while docked at the charging station; - wherein the autonomous robot further includes: - a communications device configured to communicate with the communications device on the charging station, - a motor drive powered by the re-chargeable battery and configured to propel the autonomous robot when the autonomous robot is undocked from the charging station, and - a sensor configured to measure the amount of charge provided to the motor drive by the re-chargeable battery to propel the autonomous robot when the autonomous robot is undocked from the charging station; and - wherein the communications device on the autonomous robot is configured to receive the state of charge of the autonomous robot from the charging station and wherein the autonomous robot includes a memory to store the state of charge received from the charging station; and - wherein the memory of the autonomous robot is further configured to store the amount of charge provided to the motor drive by the re-chargeable battery to propel the autonomous robot when the autonomous robot is undocked from the charging station. - an autonomous robot powered by a re-chargeable battery and having a first charging member; and - a charging station, including: - a second charging member configured to receive the first charging member on the autonomous robot when the autonomous robot is docked with the charging station for charging the rechargeable battery; - a power supply configured to charge the re-chargeable battery of the autonomous robot when docked at the charging station; - a sensor configured to measure an amount of charge transferred from the power supply to the autonomous robot during charging; - a processor, in communication with the sensor, configured to determine, from the amount of charge transferred from the power supply to the autonomous robot measured by the sensor, a state of charge of the autonomous robot; and - a communications device, in communication with the processor, configured to transmit to the autonomous robot the state of charge of the autonomous robot while docked at the charging station; - a second charging member configured to receive the first charging member on the autonomous robot when the autonomous robot is docked with the charging station for charging the rechargeable battery; - a power supply configured to charge the re-chargeable battery of the autonomous robot when docked at the charging station; - a sensor configured to measure an amount of charge transferred from the power supply to the autonomous robot during charging; - a processor, in communication with the sensor, configured to determine, from the amount of charge transferred from the power supply to the autonomous robot measured by the sensor, a state of charge of the autonomous robot; and - a communications device, in communication with the processor, configured to transmit to the autonomous robot the state of charge of the autonomous robot while docked at the charging station; - wherein the autonomous robot further includes: - a communications device configured to communicate with the communications device on the charging station, - a motor drive powered by the re-chargeable battery and configured to propel the autonomous robot when the autonomous robot is undocked from the charging station, and - a sensor configured to measure the amount of charge provided to the motor drive by the re-chargeable battery to propel the autonomous robot when the autonomous robot is undocked from the charging station; and - a communications device configured to communicate with the communications device on the charging station, - a motor drive powered by the re-chargeable battery and configured to propel the autonomous robot when the autonomous robot is undocked from the charging station, and - a sensor configured to measure the amount of charge provided to the motor drive by the re-chargeable battery to propel the autonomous robot when the autonomous robot is undocked from the charging station; and - wherein the communications device on the autonomous robot is configured to receive the state of charge of the autonomous robot from the charging station and wherein the autonomous robot includes a memory to store the state of charge received from the charging station; and - wherein the memory of the autonomous robot is further configured to store the amount of charge provided to the motor drive by the re-chargeable battery to propel the autonomous robot when the autonomous robot is undocked from the charging station.