Rocket attitude determination using a vector magnetometer
Cloutier, Paul A.
Master of Science
Two sounding rockets were launched from poker Flats Rocket Range, Alaska, on February 2 and 25, 1972, in order to study the currents associated with quiet auroral arcs. The payload contained among other instruments a vector magnetometer measuring the magnetic field along the rocket trajectory and a moonsensor giving the orientation in space of the rocket. This thesis analyzes in detail the first part of the magnetometer data reduction process using new electronic components; using then these data, we determine the attitude of the payload in space based only upon magnetometer measurements. This instrument, giving very accurate data, allows a determination of the zenith angle of the coning direction within .2° and its azimuth within 1.5° under the most favorable conditions. The results are then compared with those obtained using the magnetometer and the moonsensor. The agreement is good, though the smaller accuracy of the moonsensor leads to a larger error margin, usually twice as large. Finally, we try to use the moonsensor alone, and this gives results again in reasonable agreement with the previous ones, with an error margin five to ten times larger than with the magnetometer only. It must be emphasized that the attitude determination using the magnetometer only is not applicable in times when the geomagnetic field is strongly perturbed; only the moonsensor ought to be used then.