A method of making a multi-grained fuel grain for a rocket is disclosed, the method comprising the steps of using at least one nozzle to extrude a first propellant in an additive manufacturing process, the first propellant comprising a multi-grained fuel grain, the multi-grained fuel grain forming the at least one void, the at least one void facilitating variation in internal ballistics, forming sensors, said sensors permitting continuous monitoring and continuous modification such that a user controls the ballistics profile of a rocket motor, forming an electrically-controlled second propellant in contact with and operatively coupled to the sensors; and wherein the additive manufacturing process uses at least at least one nozzle to extrude raw materials.

An energetic ignition arrangement may comprise a pressure vessel arrangement, comprising a pressure vessel, and an ignition system arrangement. The ignition system arrangement may comprise an ignitor housing coupled to the pressure vessel and defining a sealing aperture, a seal disposed in the sealing aperture, and an electric match extending through the ignitor housing, wherein at least the ignitor housing and the pressure vessel are reusable after the energetic ignition arrangement has been employed in an ignition event.

An energetic ignition arrangement may comprise a pressure vessel arrangement, comprising a pressure vessel, and an ignition system arrangement. The ignition system arrangement may comprise an ignitor housing coupled to the pressure vessel and defining a sealing aperture, a seal disposed in the sealing aperture, and an electric match extending through the ignitor housing, wherein at least the ignitor housing and the pressure vessel are reusable after the energetic ignition arrangement has been employed in an ignition event.

Rocket tank liquid level determination, and associated systems and methods. A representative system includes a computer-readable medium having instructions that, when executed, receive an image corresponding to a view of the liquid in the rocket tank, identify an edge between the liquid and a wall of the tank, and, based on at least one of a size, shape, location, or orientation of the edge, estimate a level of the liquid in the tank. In addition to or in lieu of determining the liquid level, the system can determine a characteristic of a sloshing motion of the liquid in the tank, and, based at least on the characteristic of the sloshing motion, direct operation of a forcing element that imparts a force to the rocket to at least partially counteract a force placed on the rocket by the sloshing motion of the liquid in the tank.

Rocket tank liquid level determination, and associated systems and methods. A representative system includes a computer-readable medium having instructions that, when executed, receive an image corresponding to a view of the liquid in the rocket tank, identify an edge between the liquid and a wall of the tank, and, based on at least one of a size, shape, location, or orientation of the edge, estimate a level of the liquid in the tank. In addition to or in lieu of determining the liquid level, the system can determine a characteristic of a sloshing motion of the liquid in the tank, and, based at least on the characteristic of the sloshing motion, direct operation of a forcing element that imparts a force to the rocket to at least partially counteract a force placed on the rocket by the sloshing motion of the liquid in the tank.

A thruster control device has an opening degree estimating section and an opening degree control section. The opening degree estimating section calculates an estimated opening degree of a valve showing a rate at which the valve is opened, based on a balance of an acting force applied to a valve element of the valve to adjust a quantity of combustion gas to be ejected from a thruster and a fluid force applied to the valve element by the ejected combustion gas. The opening degree control section determines a target opening degree based on the estimated opening degree to control the opening degree of the valve.

A thruster control device has an opening degree estimating section and an opening degree control section. The opening degree estimating section calculates an estimated opening degree of a valve showing a rate at which the valve is opened, based on a balance of an acting force applied to a valve element of the valve to adjust a quantity of combustion gas to be ejected from a thruster and a fluid force applied to the valve element by the ejected combustion gas. The opening degree control section determines a target opening degree based on the estimated opening degree to control the opening degree of the valve.

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.

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.

A rocket engine benefiting from better behavior during its starting stage, the rocket engine (1) including a diverging section (13) and a lashing system (40) configured to hold the diverging section (13) while starting the rocket engine (1), the lashing system (40) comprising: a plurality of radial cables (42) connected at respective first ends to a plurality of points of the diverging section (13), and a peripheral cable (41) connected to the second ends of the radial cables (42) and configured to co-operate with attachment points (43) of a launch platform (3).