Abstract: An off-gimbal pointing system is improved using filtering of resolver and gyro responses respectively applied at the output of the resolvers and gyros for attenuating high frequencies resolver responses and gyro responses that effectively degrades the high frequency responses that are matched and above the control system bandwidth for improving the overall dynamic control of the off-gimbal pointing system for rejecting the affects of base motion disturbances and vibrations.

Abstract: The de-icing system of the present invention comprises a piezoelectric sensor means and a processor means. A piezoelectric film is the preferred sensor means and a microprocessor is the preferred processor means. In a preferred embodiment, a strip of piezoelectric film placed at a point of model kinetic energy such as the boundary layer transition point or the vortex generator of the aircraft. Such placement of the strip provides adequate airflow to excite the piezoelectric film without using a power source, thus providing a passive system. The sensor allows measurement of distributedSTATEMENT REGARDING FEDERALLY SPONSORED RESEARCHThis invention was made with Government support under Contract No. DAAH01-87-C-0860 awarded by the Defense Advanced Research Agency (DoD), Defense Small Business Innovation Research Program. The Government has certain rights in this invention.

Abstract: The change in capacitance of a sensor is linearly proportional to ice thickness provided that the ice thickness is significantly less than the distance between the conductive electrodes. By employing sensors with different electrodes, the sensitivity to ice may be traded off against the ability to measure greater ice thickness. A sensor with small spacing between electrodes will exhibit a large change in capacitance when covered by a thin layer of ice, however, the capacitance change will be linear only for very thin layers of ice. A sensor with greater spacing between electrodes is less sensitive to ice accretion but has a correspondingly greater ice thickness measurement range. Accordingly, sensor (55) is relatively sensitive and is employed to determine whether or not ice or water is present.