Tangible Play Surface Using Passive RFID Sensor Array.

We present two approaches to sensing objects on a surface, using passive Radio Frequency Identification (RFID), and explain the application of this technology to toy prototypes, Code Maker and Story Maker. In Code Maker, we created a system with an RFID antenna array on a robotic fire truck. The array senses RFID-embedded tiles as they are placed on the truck. Each tile corresponds to a command that is executed by the truck, directing to move, light up, and make sounds. In Story Maker, RFID antennas are embedded in toys that are placed on a mat, underlain with a two-dimensional array of RFID tags. The toys report their position on the mat, which triggers a scene in the story that corresponds to the configuration of toys. We describe the advantages of these RFID implementations as an alternative to other approaches, such as resistive sensing and hardware connectors.