Abstract: An evaluation system for evaluating a flow rate of a fluid coming from a tank, the system including measurement device suitable for measuring a fluid level in the tank and including estimation device for estimating the flow rate of the fluid using an unscented Kalman filter, the estimation device including an obtaining device for obtaining the raw fluid flow rate and correction device connected to the obtaining device and to the measurement device and configured to correct the raw flow rate as obtained by the obtaining device as a function of the level measured by the measurement device. A method performed by such a system.

Abstract: An obtaining step for obtaining a measurement of the monitored parameter as measured by a sensor and corresponding to an operating point of the engine, the operating point being defined by at least one regulation parameter of the engine; an estimation step for estimating a value of the monitored parameter for this operating point on the basis of a regulated value or a filtered setpoint value of the at least one regulation parameter of the engine defining the operating point; a comparison step for comparing an error between the measurement of the monitored parameter and its estimate relative to at least one threshold determined on the basis of an uncertainty on the error evaluated for the operating point; and a notification step for sending a notification in the event of the at least one threshold being crossed.

Abstract: A method of regulating pressure within a first propellant tank of a rocket engine having a first propellant tank containing a first propellant and a second propellant tank containing a second propellant, and a regulator device for regulating pressure within the first tank, the regulator device comprising a gas generator and a heat exchanger co-operating with the gas generator so as to vaporize at least part of the first propellant prior to reintroducing it into the first tank (16), the gas generator and the heat exchanger both being fed with the first propellant by a single first motor-driven pump, while the gas generator is fed with the second propellant by a single second motor-driven pump, wherein the flow rate of the first motor-driven pump is controlled as a function of a first parameter, while the flow rate of the second motor-driven pump is controlled as a function of a second parameter.

Abstract: The invention relates to the field of rocket engines, and in particular to a method and a circuit for regulating a rocket engine (1) comprising at least one combustion chamber (3) and a first liquid propellant feed circuit (10) with a first pump (12) for pumping a first liquid propellant and a first turbine (14) for actuating the first pump (12), a first feed valve (15), and a regulator device for regulating the first turbine (14). In the regulation method and circuit, an opening command (DVCH) for opening the first feed valve (15) is calculated from an external command (Cext) in application of an open loop control relationship; a command for the regulator device of the first turbine (14) is calculated on the basis of said external command (Cext) and at least one feedback value, in application of a closed loop control relationship; and the first feed valve (15) and the regulator device of the first turbine (14) are controlled in application of the respective commands.

Abstract: A feed system for feeding a rocket engine with a liquid propellant includes a feed circuit, and a device to vary a volume of gas in the feed circuit. The device is configured to cause a volume of gas in the feed circuit to vary while the rocket engine is in operation. The device to vary gas volume includes at least one variable-flow-rate gas injector to inject gas into the liquid propellant in the feed circuit. Methods of suppressing a POGO effect are also provided.

Abstract: A rocket engine feed system, includes a feed circuit including a device for varying a gas volume in the feed circuit to suppress the POGO effect. A method of suppressing the POGO effect varies at least one hydraulic resonant frequency by varying a rate at which gas is injected into the feed circuit.

Abstract: A method of characterizing a signal, the method including acquiring a signal; and determining a vibration rating of a portion of the signal; determining a level of variation of a portion of the signal; and determining information characterizing the signal by applying a function that takes as arguments the vibration rating and the level of variation.

Abstract: A technical test method for evaluating at least one operating parameter of a device over a sequence of a plurality of operating stages, each stage corresponding to a stable value of at least one operating setpoint of the device. The method including at least sampling values of the at least one operating parameter over time, filtering the sampled values in order to obtain a filtered signal for each operating parameter, calculating the variance of the sampled values for each operating parameter in a sampling window during the operating stage, calculating the absolute value of the time derivative of the filtered signal for each operating parameter and changing the value of the at least one operating setpoint when, for each operating parameter, the variance of the sampled values and the absolute value of the time derivative of the filtered signal are less than respective predetermined lower thresholds.

Abstract: A field of test methods, and more particularly to a method for testing a device, the method including one operating stage corresponding to a stable value of one operating setpoint for the device and/or for a test bench for testing the device. The operating stage is finalized before a maximum duration threshold if a criterion associated with a set of physical parameters picked up during the operating stage is satisfied and if a confidence level associated with the set of physical parameters reaches at least a predetermined threshold.

Abstract: A field of feeding propellant gas to ion thrusters, and in particular a method of feeding an ion thruster with propellant gas coming from a pressurized tank via a feed circuit including an on/off valve and, in succession downstream from the on/off valve, a high pressure restrictor, a buffer tank, and at least one low pressure restrictor. The method includes the steps of calculating a pressure setpoint for the buffer tank as a function of a flow rate setpoint, calculating the difference between the pressure setpoint for the buffer tank and a pressure measured in the buffer tank, calculating a setpoint for the opening time of the on/off valve as a function of the difference and of a pressure inside the pressurized tank, and opening the on/off valve in compliance with the opening time setpoint.

Abstract: The measurement system having multiple sensors for sensing the same physical magnitude comprises at least one set of n redundant sensors or of models representing the same physical magnitude in order to deliver n measurement signals, a fusion unit for performing fusion that is the result of multiplexing the n measurement signals in order to deliver a single multiplexed output signal resulting from the fusion of the n measurement signals, and a reconditioned UKF receiving the multiplexed output signal to output a signal constituting the best estimate of the measurement of the physical magnitude after rejecting signals representative of a sensor failure.

Abstract: A data processor system for monitoring a complex system, the processor system configured to receive a plurality of pieces of state information and to merge at least the pieces of state information into a piece of failure information, at least one of the pieces of state information being associated with a confidence flag, and the piece of failure information also being associated with a confidence flag. The system performs the merging by implementing a fuzzy logic technique to produce the piece of failure information while taking account of the respective confidence flag of the pieces of state information and to produce the confidence flag associated with the failure information.

Abstract: An information processor system for monitoring a complex system and including a mechanism receiving at least one piece of event detection information associated with a detection time and a mechanism generating at least one remanent confidence level value that decreases over time starting from the detection time.

Abstract: A mechanism for regulating an engine by using an actuator that is controlled in bang-bang mode, in which non-linearities are introduced in the control strategy in order to avoid putting excessive demand on an electric motor. The actuator is controlled by power supply pulses, which is a specific type of bang-bang control and, therefore, the actuator can receive a certain number of discrete commands. In one example, the actuator can receive two types of commands, for rotating in one direction and for rotating in the other direction.

Abstract: A method of making safe operation of a rotary assembly of a turbomachine including a turbine and a rotary machine, the method anticipating an event of exceeding a predetermined threshold speed by repetitively performing a prediction cycle including: measuring magnitudes relating to operation of the turbomachine, including real speed of rotation of its rotary assembly; based on the magnitudes, estimating driving and resisting torques applied to the rotary assembly; preparing a representative value representative of the difference between these two torques; and calculating a predicted speed of rotation for the rotary assembly at a given time horizon based on the representative value and the real speed of rotation. An action is taken on the operation of the turbomachine to limit an extent to which its rotary assembly exceeds the threshold speed in the event of the predicted speed of rotation exceeding the threshold speed.

Abstract: A system for detecting and locating failures that occur in a complex system includes elements (CAP, MODVAL, MODDP, MODFD) for detecting and locating a failure affecting at least one sub-system of the complex system. The system also includes an element (MODPD) for making a decision on any action to be taken in the event of such detection. A rocket engine can be monitored with this system.

Abstract: A rocket engine feed system, includes a feed circuit including a device for varying a gas volume in the feed circuit to suppress the POGO effect. A method of suppressing the POGO effect varies at least one hydraulic resonant frequency by varying a rate at which gas is injected into the feed circuit.

Abstract: A space launcher propulsion system includes: an engine fed by at least two propellant component tanks; a measurement mechanism to measure a quantity of propellant component actually consumed in each of the tanks, by sensors becoming uncovered; an estimation mechanism to estimate instantaneous flow rates of each of the propellant components on the basis of at least one operating parameter of the engine; and a correction mechanism correcting the way the estimation mechanism estimates on the basis of the measured consumed quantities and of the estimated instantaneous flow rates.

Abstract: A system for detecting and locating failures that occur in a complex system includes elements (CAP, MODVAL, MODDP, MODFD) for detecting and locating a failure affecting at least one sub-system of the complex system. The system also includes an element (MODPD) for making a decision on any action to be taken in the event of such detection. A rocket engine can be monitored with this system.

Abstract: The invention relates to a system for regulating the temperature of a fuel cell that is cooled by a cooling fluid traveling through the cell, the system including both first control means for measuring the temperature of the cooling fluid and for controlling the flow rate of the controlling fluid as a function of said measured temperature of said cooling fluid, comprising second control means for measuring the flow rate of the cooling fluid and for controlling the temperature of the cooling fluid as a function of a flow rate difference between the command flow rate specified by said first control means and said corresponding measured flow rate of the cooling fluid such that said command temperature specified by the second control means compensates for said flow rate difference.