Precision Attitude Sensing on Aerostats (PASA)

Archangel's Air Data Attitude Heading Reference System (ADAHRS) is a solid-state unit that integrates low-cost piezoelectric MEMS gyros and accelerometers, as well as pitot and static sensing devices and a magnetometer with a local processor. Accuraciesto 1 degree RMS have been demonstrated in aircraft test flights. Long term stability of the ADAHRS has been demonstrated to be better than 1 degree hr/yr. The gyro sensors used in the construction of the original ADAHRS were low cost without reproduciblethermal profiles. All drift in the ADAHRS is therefore estimated on line using a proprietary technique called FLASP (Fuzzy Logic Adaptive Signal Processing). By replacing the existing gyro sensors with the new sensors and modifying the FLASP algorithm,the RMS attitude errors can be significantly reduced.Following this approach and using proprietary shock isolation, an IMU of inertial quality can be produced with MEMS devices in a 1