Patent ID: 7853362
Filing Date: 2010-12-14
Classification: A61M,F04B,G05D,Y10T

Abstract:
1. A method for estimating a relative elevation between a first location and a second location, the method comprising: placing a fluid flow control device at the first location, the fluid flow control device having a membrane pump in fluid communication through a valve with the second location, the membrane pump having a pressure transducer; isolating the membrane pump from the second location; calibrating the pressure transducer; establishing fluid communication between the membrane pump and the second location; measuring pressure in the membrane pump with the pressure transducer; and estimating the relative elevation based on the pressure; wherein the step of calibrating comprises filling the membrane pump with fluid in pressure equilibrium with the pressure at the first location; measuring a first calibration pressure in the membrane pump; filling the membrane pump with fluid in pressure equilibrium with a known calibration pressure; measuring a second calibration pressure in the membrane pump; and estimating the relative elevation by constructing a mathematical fit between the pressure and relative elevation based on the known calibration pressure, the first calibration pressure, and the second calibration pressure.