Robot localization system

Abstract

A robot localization system is provided. The robot localization includes a robot, which moves within a predetermined space and performs predetermined tasks, and a docking station corresponding to a home position of the robot. The docking station includes a first transmitting unit, which transmits a sound wave to detect a position of the robot; and a second transmitting unit, which transmits a synchronizing signal right when the sound wave is transmitted. The robot includes a first receiving unit, which comprises at least two sound sensors receiving the sound wave incident onto the robot; a second receiving unit, which receives the synchronizing signal incident onto the robot; a distance calculation unit, which calculates a distance between the first transmitting unit and the first receiving unit using a difference between an instant of time when the synchronizing signal is received and an instant of time when the sound wave is received; and an incident angle calculation unit, which calculates an incident angle of the sound wave onto the robot using a difference between receiving times of the sound wave in the at least two sound sensors comprised in the first receiving unit.

1 . A robot localization system including a robot, which moves within a predetermined space and performs predetermined tasks, and a docking station corresponding to a home position of the robot,
 the docking station comprising:   a first transmitting unit, which transmits a sound wave to detect a position of the robot; and   a second transmitting unit, which transmits a synchronizing signal right when the sound wave is transmitted,   the robot comprising:   a first receiving unit, which comprises at least two sound sensors receiving the sound wave incident onto the robot;   a second receiving unit, which receives the synchronizing signal incident onto the robot;   a distance calculation unit, which calculates a distance between the first transmitting unit and the first receiving unit using a difference between an instant of time when the synchronizing signal is received and an instant of time when the sound wave is received; and   an incident angle calculation unit, which calculates an incident angle of the sound wave onto the robot using a difference between receiving times of the sound wave in the at least two sound sensors comprised in the first receiving unit.   
     
     
         2 . The robot localization system of  claim 1 , wherein the sound wave is a supersonic wave. 
     
     
         3 . The robot localization system of  claim 1 , further comprising an encoder, which measures a positional change between a previous position and a current position of the robot and a directional change between a previous orientation and a current orientation of the robot. 
     
     
         4 . The robot localization system of  claim 3 , further comprising a state observer, which estimates a current position and a current orientation of the robot with respect to the docking station using the distance between the first transmitting unit and the first receiving unit, the incident angle of the sound wave, the positional change, and the directional change. 
     
     
         5 . The robot localization system of  claim 4 , wherein the state observer comprises a Kalman filter which estimates the orientation of the robot using the positional and directional changes measured by the encoder. 
     
     
         6 . The robot localization system of  claim 1 , further comprising a unit for measuring an absolute azimuth of the robot. 
     
     
         7 . The robot localization system of  claim 6 , further comprising a Kalman filter which filters measurement noise of the unit for measuring the absolute azimuth of the robot.