Off-center parachute flight termination system including latch mechanism disconnectable by burn wire

Patent metadata

Field	Value
Publication number	US-11518514-B2
Application number	US-202017605754-A
Country	US
Kind code	B2
Filing date	Apr 23, 2020
Priority date	Apr 25, 2019
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

Systems, devices, and methods including: a latching mechanism comprising: a first latch configured to attach to a door of an unmanned aerial vehicle (UAV); a second latch configured to attach to a portion of the UAV distal from the first latch; a string connected between the first and second latch, where the string secures the door shut; at least two radio modules in communication with a ground control station; and at least two burn wires in contact with a portion of the string between the first latch and the second latch; where current from a backup battery passes to at least one burn wire when the burn signal is received, where the burn wire causes the connection between the first latch and the second latch to be broken and the door of the UAV is separated from the UAV, and where the parachute is deployed when the door of the UAV is separated from a rest of the UAV.

First claim

What is claimed is:

1. A system, comprising:
a latching mechanism, wherein the latching mechanism comprises:
a first latch configured to attach to a door of an unmanned aerial vehicle (UAV);
a second latch configured to attach to a portion of the UAV distal from the first latch;
a string connected between the first latch and the second latch, wherein the string secures the door of the UAV shut;
at least two radio modules in communication with a ground control station; and
at least two burn wires in contact with a portion of the string between the first latch and the second latch, wherein each burn wire of the at least two burn wires is attached to a respective radio module of the at least two radio modules;
wherein at least one of the at least two radio modules are configured to receive a burn signal from the ground control station, wherein current from a backup battery passes to a corresponding burn wire of the at least two burn wires based on receiving the burn signal, wherein the corresponding burn wire is attached to the radio module that is configured to receive the burn signal, wherein the burn wire is configured to melt the portion of the string in contact with the burn wire causing the connection between the first latch and the second latch to be broken, and wherein the door of the UAV is separated from a rest of the UAV when the connection between the first latch and the second latch is broken.

2. The system of claim 1 , further comprising:
a parachute disposed in the UAV, wherein the parachute is deployed when the door of the UAV is separated from the UAV.

3. The system of claim 2 , wherein the parachute is disposed off-center of the UAV.

4. The system of claim 3 , wherein deploying the parachute causes a drag force on a first side of the UAV, wherein the drag force slows down the first side of the UAV more than a second opposite side of the UAV inducing a torque on the UAV which results in a rotation of the UAV, and wherein the drag force combined with the induced torque causes the UAV to exit a current flight pattern and spiral down towards the ground.

5. The system of claim 1 , wherein the at least two radio modules comprise:
a first radio module; and
a second radio module.

6. The system of claim 5 , wherein the first radio module comprises:
an antenna; and
an interface configured to receive the burn signal from the antenna, wherein the interface toggles the backup battery to pass current to a first burn wire of the at least two burn wires.

7. The system of claim 1 , wherein the ground control station is in communication with a terrestrial GPS receiver, a terrestrial RF emitter, a terrestrial RF receiver, and a visual band emitter.

8. The system of claim 1 , wherein the string is made of a combustible material.

9. The system of claim 1 , wherein the at least two burn wires are made of nichrome (NiCr).

10. A method, comprising:
receiving a burn signal at an interface of a first radio module of two or more radio modules of a latching mechanism;
toggling, via the interface, at least one backup to pass current from the backup to a first conducting burn wire of the first radio module, wherein the first conducting burn wire is attached to a portion of a string; and
melting, by the first conducting burn wire, the portion of the string connected between a first latch and a second latch, wherein the first latch is configured to attach to a door of an unmanned aerial vehicle (UAV), wherein the second latch is configured to attach to a portion of the UAV distal from the first latch, and wherein the string secures the door of the UAV shut prior to being melted.

11. The method of claim 10 , further comprising:
separating the door of the UAV from a rest of the UAV when the connection between the first latch and the second latch is broken.

12. The method of claim 11 , further comprising:
deploying an off-center parachute when the door of the UAV separates from the UAV.

13. The system of claim 12 , wherein deploying the parachute causes a drag force on a first side of the UAV, wherein the drag force slows down the first side of the UAV more than a second opposite side of the UAV inducing a torque on the UAV which results in a rotation of the UAV, and wherein the drag force combined with the induced torque causes the UAV to exit a current flight pattern and spiral down towards the ground.

14. The method of claim 10 , wherein the string is made of a combustible material.

15. The method of claim 10 , wherein the first conducting burn wire is made of nichrome (NiCr).

16. The method of claim 10 , further comprising:
determining that the door did not separate from a rest of the UAV;
receiving a second burn signal at a second interface of a second radio module of the two or more radio modules of the latching mechanism;
toggling, via the second interface, the at least one backup to pass current from the backup to a second conducting burn wire of the second radio module, wherein the second conducting burn wire is attached to a portion of the string; and
melting, by the second conducting burn wire, the portion of the string connected between the first latch and the second latch.

Assignees

• Aerovironment Inc

Inventors

• Lisoski Derek
• Sechrist William Stuart

Classifications

• B64D17/34

  adapted to control direction or rate of descent · CPC title

• B64D17/62

  Deployment · CPC title

• B26F3/12

  with heated wires · CPC title

• B64D17/80

  in association with aircraft, e.g. for braking thereof · CPC title

• B64C2201/185

  Operations & Transport · mapped topic