A Hemispherical Sun Sensor for Orientation and Geolocation

We propose a novel sensing system with a hemispherical arrangement of light intensity sensors to determine the vector to the dominant light source in its environment. We apply this system to the measurement of sun vector. The accuracy of our sensor is proved to be scalable when using more sensing pixels. Our experimental data yields the solar azimuth to within 5° and the solar zenith to within 1° using only five light intensity sensors. A sensor operation procedure is provided to improve sensor accuracy. A method is shown that determines absolute orientation and location from the measured sun vector. The corresponding uncertainty analysis is also presented.