Patent ID: 8781652
Filing Date: 2014-07-15
Classification: B64G,G01F

Abstract:
1. A computer-implemented method comprising: receiving pressure telemetry data and temperature telemetry data for a propellant tank of a satellite over a time interval, the propellant tank having a known geometry and containing an amount of propellant and a volume of a pressurant; calculating a metric relating the volume of the pressurant, the pressure telemetry data and the temperature telemetry data, the metric calculation comprising reconstructing, based on the received temperature telemetry data, a predicted set of pressure data for the time interval and comparing the predicted set of pressure data to at least part of the pressure telemetry data, and wherein reconstructing comprises assuming a direct proportionality between the predicted set of pressure data and the temperature telemetry data; solving for a most likely estimate of the volume of the pressurant to optimize the metric; determining, based on the most likely estimate of the volume of the pressurant and the known geometry of the propellant tank, the most likely amount of propellant remaining in the propellant tank; and wherein the receiving, calculating, solving and determining are performed by at least one system comprising at least one programmable processor.