| TRACK was developed by Abbess Instruments in the 1980's. It allows tracking and characterization of a single magnetic dipole introduced into an essentially static known background field. The algorithm's distinguishing feature is its ability to provide a definite single-valued tracking solution given one measurement of ambient magnetic field characteristics at a single point in space. The algorithm is fairly simple, and for that reason a single magnetic sensor of appropriate design coupled with it, can track a rapidly moving magnetic object in real time.
Stated precisely , TRACK allows one to determine the position, magnitude, and direction of a single magnetic dipole given:
Since the magnetic field derivative matrix is symmetric and trace less, it is determined by 5 values. The magnetic field is determined by its three components. Thus TRACK requires exactly eight numbers to place and characterize a given dipole introduced against a known background field. Given this input the dipole's position, magnitude and direction can be uniquely determined through mathematical calculation alone, without any additional empirical information. Hence an appropriate sensor to use with TRACK is the so called Eight Track Magnetometer - Gradiometer which measures three field components and 5 derivatives at a time. TRACK insures that the data from the sensor is used in an optimal manner by rotating the coordinate system in which calculations are done to minimize error. TRACK gives a means by which an anomalous dipole introduced against a known background field can be tracked and characterized in real time. This has application in any situation where it is desirable to track moving magnetic objects or where a magnetic object lost in an area of known magnetic field needs to be found. The algorithm is practical even in a situation where dipoles are continually entering and leaving the scene since the background field measurement can be continually updated, allowing one to keep track of a multitude of magnetic anomalies if their velocities at any given time are sufficiently distinct. The high speed at which the algorithm can be run and the fact that it needs only a single eight track reading to position a dipole relative to the sensor, makes possible the real time tracking of anomalous magnetic objects in field situations.
If you have any questions or would like to discuss an application or demonstration with us. Please feel free to e-mail or call Geoffrey Zeamer at abbess@abbess.com |
