摘要 |
To monitor continuously the propellant consumption of a space vehicle equipped with a plurality of propulsion units operated by activator means according to activation instructions received by the activator means, the number N of activation instructions applied to each propulsion unit from a reference time and their cumulative duration S are memorized. The mass M of propellant consumed since the reference time by each propulsion unit is computed from the equation: M = f(N) + g(S) In this equation, f and g are independent predetermined functions. The masses consumed by each propulsion unit are summed. The functions f(N) and g(S) may be such that the above equation can be re-written: M = (? x S) + (mo x N) In this equation ? is an average propellant flowrate during the activation of a given propulsion unit and mo is a predetermined fixed mass. |