RFID for aiding the visually impaired recognize surroundings

For a visually impaired person identifying the landmark he is expecting in his cognitive map is crucial. To let him do this, we approach as follows: we set landmarks in the environment by RFIDs and then we identify, trace and localize them. In the first part we describe our approach in detail, including landmarking by passive RFIDs and tracing them by autonomous robots. As visually impairedness badly interfere with the detection of changes in the environment, in the second part, we describe localization of active RFIDs which are deployed in the room and subject to spontaneous move. Our approach for this problem is: 1. place several anchoring (fixed) RFIDs, 2. for the estimation of a possible location of movable RFIDs we use clustering by SOM, 3. we navigate robots iterating the estimation algorithm until we reach the desired object (RFID).