An Indoor Location Tracking using Wireless Sensor Networks Cooperated with Relative Distance Fingerprinting

We present a method of moving path control of an automatic guided vehicle (AGV) in an indoor environment through recognition of markers. A linear relationship between the relative distance to a marker from the current location of an AGV and the size of the recognized marker image can be built. Thus using the length of the recognized marker image as a fingerprint instead of the received signal strength (RSS) may result in a more reliable estimation of the location. Our simulation results show that the maximum localization error is less than 2cm and thus the range of the estimation error is ±0.025%. The main advantage of the proposed system is that they are highly flexible for on-demand delivery to any location.