RFID-enabled Target Tracking and Following with a Mobile Robot Using Direction Finding Antennas

Summary This paper presents novel application of RFID for robot target tracking and following. Authors have utilized the cheap though effective RFID technology for the purpose. These antennas receive the signal form the RFID transponder which generates the voltage which depends on angle of orientation of the antenna (sin of the angle)with respect to the transponder. This variation in the voltage can be used to find the direction of transponder .In order to find the direction correctly; they have used dual antennas which are at 90 degree phase difference. S The ration between the voltage can be calibrated to the angle information of the transponder (as the v1/v2= tan(theta), where theta is the angle between the transponder direction and the line of sight of the transponder with respect to the vertex of the angle formed by the two antennas.

The set of antennas is connected to an actuator, controlled by a micro controller, which is programmed to rotate the antennas such that the ratio (v1/v2) remains 1. This ensures that the transponder is always in the direction given by the angle bisector of the two antennas. The change in the direction triggered by the actuator is mapped to the actual direction of motion of the robot. Thus the robot can be made to track either another robot or reach some static destination.


Discussion:

This paper as discussed by all is more relevant to Robotic navigation and Rather than RFID. Though, it has given some good cue about utilizing the information based on the voltage ratios for direction tracking. May be we can club this information with the data gloves to get the 3D information about the hand position. I think if we can use a similar setup (orthogonal antennas) as a receiver and some RFID transmitter (tags) on the gloves, the ratio can be utilized to track the hand in 3D space with respect to the vertex of the receiver. Over all I liked this simple and straightforward approach.