Trajectory shaping

Patent metadata

Field	Value
Publication number	US-11946727-B2
Application number	US-202017765148-A
Country	US
Kind code	B2
Filing date	Oct 8, 2020
Priority date	Oct 10, 2019
Publication date	Apr 2, 2024
Grant date	Apr 2, 2024

Abstract

The presently disclosed subject matter includes a system and a method for launching a projectile towards a target, wherein the system comprises a control circuitry, a booster engine, and one or more thrusters adapted to be connected to the projectile and capable of being spun during launch around a longitudinal axis of the projectile, the control circuitry being operatively connected to the one or more thrusters; wherein responsive to ignition of propellant stowed in a combustion chamber of the booster engine, the booster engine causes the projectile to launch from its cell; following launch of the projectile, cause the projectile to turn at a certain rate and a certain azimuth.

First claim

The invention claimed is:

1. A system for launching a projectile towards a target, the system comprising:
a control circuitry;
a booster engine; and
one or more thrusters adapted to be connected to the projectile and capable of being spun during launch around a longitudinal axis of the projectile, the control circuitry being operatively connected to the one or more thrusters;
wherein the booster engine is configured such that ignition of propellant stowed in a combustion chamber of the booster engine, initiates a sequential execution of a first burning phase, a second burning phase and a third burning phase of the propellant; wherein during the first burning phase the projectile is ejected from a cell and wherein thrust generated by burning of the propellant during the second burning phase is lower than the thrust generated during the first and the third burning phases;
wherein the control circuitry is configured to activate during the second burning phase the one or more thrusters; wherein upon the activation, the projectile begins to turn in a certain deflection azimuth that is dependent on activation timing.

2. The system of claim 1 , wherein during the first burning phase the projectile is ejected from the cell and the one or more thrusters are spun around a longitudinal axis of the projectile; wherein the control circuitry is configured to activate the one or more thrusters according to the activation timing, wherein the activation timing is calculated according to a desired deflection azimuth.

3. The system of claim 1 , wherein activation of the one or more thrusters is executed according to a selected activation profile, wherein the activation profile is selected according to a desired deflection angle of a velocity vector of the projectile.

4. The system of claim 3 , wherein the activation profile comprises data indicating, for each one of the one or more thrusters, a respective spin-cycle for activation.

5. The system of claim 3 , wherein the activation profile defines for a specific combination of one or more thrusters, activation timing of each thruster relative to activation timing of a first thruster.

6. The system of claim 2 , wherein the control circuitry is configured to calculate the activation timing of the one or more thrusters, based on data including: initial angular position of at least one thruster, spin rate and a position of the target.

7. The system of claim 1 , wherein the one or more thrusters include two or more thrusters and wherein the control circuitry is further configured, following activation of a first thruster, to update a respective activation timing of one or more additional thrusters, according to the actual deflection azimuth and deflection angle rate, resulting from one or more previous activations of thrusters.

8. The system of claim 2 , further comprises an off-board processing circuitry, external to the projectile, configured to calculate an activation timing of at least one thruster of the one or more thrusters, based on data including: direction of the target, nominal spin rate of the projectile and nominal thrust of the one or more thrusters.

9. The system of claim 2 , wherein the cell is designed with a spiral groove along its internal surface and the projectile comprises a pin attached to its body; wherein the projectile is stored in the cell with the pin positioned within the groove and upon launch, the projectile is pushed out of the cell while the pin situated in the groove causing the projectile to spin around its longitudinal axis.

10. The system of claim 2 , wherein the one or more thrusters are installed in a thrusters-belt fixed to the projectile in a manner allowing the belt to spin freely around the projectile and wherein spinning of the belt is executed by any one of:
a. an onboard spinning mechanism operatively connected to the belt; or
b. a pin attached to the belt which is situated within a spiral grooved disposed along an internal surface of the cell, wherein upon launch, the projectile is pushed out of the cell and the pin and the spiral groove cause the belt to spin around its longitudinal axis.

11. The system of claim 1 , wherein thrust generated during the second burning phase is at least two times lower than the thrust of the first burning phase.

12. The system of claim 1 , wherein a duration of thrust generated by any one of the one or more thrusters is shorter than a duration of a thruster spin-cycle.

13. The system of claim 1 , wherein the one or more thrusters comprise a plurality of thrusters and wherein the control circuitry is further configured following activation of a first thruster of the plurality of thrusters to:
measure real-time data including deflection azimuth and/or deflection angle rate; compare the measured real-time data with an expected data; in case a deviation between measured data and expected data is identified, update thruster activation parameters to rectify the deviation.

14. A method of launching a projectile towards a target, the method comprising:
in response to a command to launch the projectile towards the target:
igniting propellant stowed in a combustion chamber of the projectile; wherein ignition of the propellant initiates a sequential execution of a first burning phase, a second burning phase and a third burning phase of the propellant; wherein during the first burning phase the projectile is ejected from a cell and wherein thrust generated by burning of the propellant during the second burning phase is lower than the thrust generated during the first burning phase and the third burning phases;
ejecting, during the first burning phase, the projectile out of a cell in a manner that causes one or more thrusters fixed to the projectile, to spin around a longitudinal axis of the projectile;
activating, during the second burning phase, the one or more thrusters; wherein the one or more thrusters are fixed to the projectile, such that upon an activation of the one or more thrusters, the projectile begins to turn in a certain deflection azimuth according to activation timing.

15. The method of claim 14 further comprising, activating the one or more thrusters according to the activation timing, wherein the activation timing is calculated according to a desired deflection azimuth.

16. The method of claim 14 further comprising: selecting an activation profile according to a desired deflection angle of velocity vector of the projectile; and activating the one or more thrusters according to the selected activation profile.

17. The method of claim 16 , wherein the activation profile defines for a specific combination of one or more thrusters an activation timing of each thruster relative to the activation timing of a first thruster.

18. The method of claim 15 , further comprising: calculating the activation timing of the one or more thrusters, based on data including: an initial angular position of at least one thruster, spin rate of the projectile and a position of the target.

19. The method of claim 14 , wherein the one or more thrusters include two or more thrusters and wherein the method further comprising:
following activation of a first thruster, updating a respective activation timing of one or more additional thrusters, according to the actual deflection azimuth and deflection angle rate, resulting from one or more previous activations of one or more thrusters.

20. The method of claim 15 , further comprising: maintaining the projectile in the cell having a spiral groove along its internal surface while a pin

Assignees

• Israel Aerospace Ind Ltd

Inventors

• Rovinsky Jacob

Classifications

• F42B10/668 Primary

  Injection of a fluid, e.g. a propellant, into the gas shear in a nozzle or in the boundary layer at the outer surface of a missile, e.g. to create a shock wave in a supersonic flow · CPC title

• F41F3/04 Primary

  for rockets · CPC title

• F41G7/36

  using inertial references · CPC title

• F42B10/26

  using spin (F42B10/04, F42B10/12, F42B10/14, F42B10/24, F42B14/02 take precedence) · CPC title

• F41G7/346 Primary

  using global navigation satellite systems, e.g. GPS, GALILEO, GLONASS · CPC title