Patent ID: 6860136

Claim:
A method for determining density of an object, comprising: (a) completely immersing the object in a gaseous medium; (b) causing the gaseous medium to have a first density; (c) determining the first density of the gaseous medium; (d) exposing the object to an acceleration in a first direction while immersed in the gaseous medium having the first density; (e) determining a first applied force in a second direction opposite the first direction, where the first applied force is sufficient to maintain the object in static equilibrium while the acceleration is applied and the object is immersed in the gaseous medium having the first density, (f) causing the gaseous medium to have a second density which differs from the first density; (g) determining the second density of the gaseous medium; (h) exposing the object to the acceleration in the first direction while immersed in the gaseous medium having the second density; (i) determining a second applied force in the second direction which is sufficient to maintain the object in static equilibrium while exposed to the acceleration and immersed in the gaseous medium having the second density; (j) completely immersing a calibration standard of known density in the gaseous medium having the first density; (k) exposing the calibration standard to the acceleration in a first direction while immersed in the gaseous medium having the first density; (l) determining a third applied force in the second direction, where the third applied force is sufficient to maintain the calibration standard in static equilibrium while the acceleration is applied and the calibration standard is immersed in the gaseous medium having the first density; (m) exposing the calibration standard to the acceleration in the first direction while immersed in the gaseous medium having the second density; (n) determining a fourth applied force in the second direction which is sufficient to maintain the calibration standard in static equilibrium while exposed to the acceleration and immersed in the gaseous medium having the second density; (o) calculating a calibration ratio based on the third and fourth applied forces, the first and second densities of the gaseous medium, and the known density of the calibration standard; and (p) determining the density of the object based on the first and second densities of the gaseous medium, the first and second applied forces, and the calibration ratio.