Patent ID: 8121728

Claim:
A robot system comprising: a robot apparatus; and several wireless communication devices, for sending radio frequency (RF) signals of identification (ID) codes; wherein the robot apparatus comprises: a communicating unit, for receiving the RF signals of ID codes from the wireless communication devices within a predetermined area and time period; a sensing unit, for sensing people and obtaining the number of people within the predetermined area and time period; a buffer unit, for storing previous and current condition data, wherein the previous data, which is initialized to null, comprise ID codes and the number of people updated and stored at a previous time, and the current data comprise current ID codes and the number of people in the predetermined area as determined by the communicating unit and the sensing unit; a storage unit, for storing an output table which respectively associates a plurality of outputs with various combinations and/or changes; a processing unit comprising: an ID presence determining (IDPD) module, for comparing the current ID codes and the number of people with previous data stored previously in the buffer unit, and generating an update signal when the comparison is not equal; an updating module, for replacing the previous data with the current data based on the update signal; and an output decision module, for acquiring output data in the storage unit associated with any differences between previous data and current data in the output table; and an output unit, for performing an output according to the output data.