Model based contact predictor

Patent metadata

Field	Value
Publication number	US-10017263-B2
Application number	US-201715422941-A
Country	US
Kind code	B2
Filing date	Feb 2, 2017
Priority date	Apr 11, 2016
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

An impact mitigation system for an aircraft and method of deploying the impact mitigation system is disclosed. A state parameter of the aircraft is obtained. The state parameter is used with an aircraft performance model to determine an acceleration capability of the aircraft. A trajectory of the aircraft is predicted using the state parameter of the aircraft and the acceleration capability of the aircraft. A location of an object with respect to the aircraft is determined and the impact mitigation system is deployed when the predicted trajectory indicates a contact with the object at a predicted contact velocity higher than a threshold velocity at a future time.

First claim

Having thus described the invention, it is claimed:

1. A method of deploying an impact mitigation system for an aircraft, comprising:
obtaining a state parameter of the aircraft;
determining an acceleration capability of the aircraft using the state parameter and an aircraft performance model;
predicting a trajectory of the aircraft using the state parameter of the aircraft and the acceleration capability of the aircraft;
determining a location of an object with respect to the aircraft; and
deploying the impact mitigation system when the predicted trajectory indicates a contact with the object at a future time.

2. The method of claim 1 , further comprising using the state parameter and a rotor thrust model of the aircraft performance model to determine a rotor thrust capability of an engine of the aircraft and determining the acceleration capability of the aircraft from the rotor thrust capability.

3. The method of claim 2 , further comprising determining the acceleration capability of the aircraft from the rotor thrust capability and a mass of the aircraft.

4. The method of claim 2 , wherein determining the rotor thrust capability includes at least one of: (i) determining a force provided by a rotor of the aircraft; (ii) determining a force on the aircraft due to ground effect; (iii) determining an effect of atmospheric conditions on the force provided on the aircraft; and (iv) determining a force adjustment based on an engine capabilities and rotor speed.

5. The method of claim 1 , further comprising performing an integration using the determined acceleration capability and the state parameter to predict a trajectory envelope of the aircraft.

6. The method of claim 1 , further comprising comparing the predicted trajectory envelope of the aircraft to a model of a terrain to predict an unavoidable contact of the aircraft with a feature of the terrain.

7. The method of claim 6 , further comprising predicting a contact velocity of the aircraft and deploying the impact mitigation system when the predicted contact velocity exceeds a threshold velocity.

8. The method of claim 1 , wherein the state parameter further comprises at least one of: (i) an attitude of the aircraft; and (ii) a velocity of the aircraft.

9. The method of claim 1 , wherein the deploying the impact mitigation system includes at least one of: (i) deploying an external airbag; and (ii) deploying a landing gear.

10. An impact mitigation system for an aircraft, comprising:
a state sensor for obtaining a state parameter of the aircraft;
a surveillance sensor for determining a location of an object with respect to the aircraft; and
a processor configured to:
determine an acceleration capability of the aircraft using the state parameter and an aircraft performance model,
predict a trajectory of the aircraft using the state parameter of the aircraft and the acceleration capability of the aircraft, and
deploy the impact mitigation system when the predicted trajectory indicates a contact with the object at a future time.

11. The aircraft of claim 10 , wherein the processor determines a rotor thrust capability of an engine of the aircraft using the state parameter of the aircraft and a rotor thrust model of the aircraft performance model and determines the acceleration capability of the aircraft from the rotor thrust capability.

12. The aircraft of claim 11 , wherein the processor is further configured to determine the rotor thrust capability by determining at least one of: (i) a force provided by a rotor of the aircraft; (ii) a force on the aircraft due to ground effect; (iii) an effect of atmospheric conditions on the force provided on the aircraft; and (iv) a force adjustment based on a capability of an engine and a rotor speed of the aircraft.

13. The aircraft of claim 10 , wherein the processor further predicts a contact velocity of the aircraft and deploys the impact mitigation device when the predicted contact velocity exceeds a threshold velocity.

14. The aircraft of claim 10 , wherein the state parameter further comprises at least one of: (i) an attitude of the aircraft; and (ii) a velocity of the aircraft.

15. The aircraft of claim 10 , wherein the impact mitigation device includes at least one of: (i) an external airbag; and (ii) a landing gear.

Assignees

• Sikorsky Aircraft Corp

Inventors

• Litwinowicz Anthony
• Cheng Kwok

Classifications

• B64D25/00 Primary

  Emergency apparatus or devices, not otherwise provided for · CPC title

• B64C25/00

  Alighting gear (air-cushion alighting gear B60V3/08) · CPC title

• B64D2201/00

  Airbags mounted in aircraft for any use · CPC title

• B64C27/04

  Helicopters · CPC title

• B64D45/00

  Aircraft indicators or protectors not otherwise provided for · CPC title