Mobile robot localization scheme based on RFID and sonar fusion system

We propose a novel algorithm for improved localization of the mobile robots by fusing RFID localization system and ultra-sonic sensors. Because there are uncertainties in previous RFID localization system, we are focusing on the sensor fusion system, which removes the uncertainty of the robot location using the distance measurements by ultra-sonic sensors. We divide into 2 parts, which are GPE (global position estimation) by RFID localization system and LEC (local environment cognition) by ultra-sonic sensor. The scheme to remove the uncertainty is proposed, which are the modeling about the measurement noise for RFID localization system and to estimate the straight obstacle and circular obstacle in well-structural indoor environment by the ultra-sonic sensors. The hierarchical localization algorithm is proposed to estimate the position of the mobile robot from GPE and LEC and for robust localization under the unknown indoor environment.