ROBERT JOHN HANSMAN, JR
Pilots at Sacramento St, Cambridge, MA

4729245, Mar 8, 1988

Jan 2, 1986

6/815583

Robert J. Hansman - Cambridge MA

Massachusetts Institute of Technology - Cambridge MA

G01F 1700

73865

A substantially fluid orientation insensitive, simple, relatively inexpensive gauge for measuring the quantity (mass/volume) of a liquid, such as fuel, stored in a tank subjected to low gravity conditions is disclosed. The gauge comprises, in general, a transmitter and a receiver coupled to a liquid storage tank in which a liquid of known dielectric behavior, such as fuel for a space vehicle, is stored. The transmitter comprises an R. F. oscillator for generating R. F. energy across a predetermined variable frequency range. The transmitted R. F. energy is coupled to an antenna inserted into the tank and is also coupled to an R. F. energy detector. The receiver measures the received power as a function of frequency above and below the dominant resonant frequency, or harmonics thereof. The measured power decreases substantially before and after resonance because, at resonance, most of the power is absorbed or stored in the cavity and less is transmitted to the receiver. The measured power versus frequency as sensed by the receiver is used to calculate the quality factor, "Q" which is inversely proportioned to the amount of fluid in the tank.

5313202, May 17, 1994

Jan 25, 1993

8/008822

Robert J. Hansman - Cambridge MA
Adam L. Dershowitz - New York NY

Massachusetts Institute of Technology - MA

G08B 2100

340962

Method and apparatus for detecting icing, particularly on airfoils such as helicopter rotor blades, by detecting warming caused by latent heat released as water freezes. The sensors may be multiple or single, contact or remote.