Autonomous flight safety system

Patent metadata

Field	Value
Publication number	US-12175877-B2
Application number	US-202117469024-A
Country	US
Kind code	B2
Filing date	Sep 8, 2021
Priority date	Sep 8, 2021
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

The present disclosure describes autonomous flight safety systems (AFSSs) that incorporate an autonomous flight termination unit (AFTU) enabling AFSS monitoring for various termination conditions that are used to activate a flight termination system (e.g., in the event a termination condition is detected). Such termination conditions include boundary limit detection (e.g., whether a vehicle position is outside or projected outside a planned flight envelope), as well as body instability detection (e.g., whether a pitch rate and yaw rate exceed some threshold indicative of vehicle instability). For instance, an AFTU may incorporate a three-axis gyroscope sensor and may implement instability detection processing based on information obtained via the sensor. Instability detection processing may include, for example, a BID algorithm that may be implemented by an AFTU to monitor angular rates of the vehicle, to determine if the vehicle is no longer under stable control, and to issue termination commands when termination conditions are detected.

First claim

What is claimed is:

1. An autonomous flight safety system comprising:
a position sensing system communicatively coupled to a processor and comprising at least one sensor configured to sense a real-time position in three-dimensional space of a launch vehicle and generate a location signal indicative of the real-time position in three-dimensional space of the launch vehicle;
a three-axis gyro communicatively coupled to the processor and configured to generate a gyro signal indicative of a pitch rate and yaw rate of the launch vehicle;
a flight termination unit communicatively coupled to the processor and configured to terminate the launch vehicle upon activation of the flight termination unit; and
an autonomous flight termination unit comprising:
the processor;
processor-readable memory; and
software stored on the processor-readable memory and configured to run on the processor, wherein the autonomous flight termination unit is adapted to perform the following steps:
receive repeatedly, from the position sensing system, the location signal indicative of the real-time position in three-dimensional space of the launch vehicle;
receive repeatedly, with the three-axis gyro communicatively coupled to the processor, the gyro signal indicative of a pitch rate and yaw rate of the launch vehicle;
determine, repeatedly, using at least the gyro signal as input to an algorithm including pre-determined mission rules governing expected launch vehicle behavior, whether the launch vehicle is in an unstable condition, wherein the unstable condition includes tumbling of the launch vehicle, wherein the algorithm includes comparing the pitch rate and yaw rate indicated by the gyro signal with a maximum prescribed pitch rate and yaw rate; and
upon determining that the launch vehicle is in an unstable condition, activate the flight termination unit, whereby in response to the activation, the launch vehicle is terminated.

2. The autonomous flight safety system of claim 1 comprising:
said position sensing system comprising a global positioning system receiver.

3. The autonomous flight safety system of claim 2 comprising:
said position sensing system further comprising an inertial navigation system.

4. The autonomous flight safety system of claim 1 further comprising:
a global positioning system receiver; and
said autonomous flight termination unit, wherein said autonomous flight termination unit is coupled to the global positioning system receiver, wherein the global positioning system receiver generates said location signal, and wherein said position sensing system receives said location signal.

5. The autonomous flight safety system of claim 1 further comprising:
said autonomous flight termination unit, wherein said autonomous flight termination unit is adapted to perform the following steps:
said receiving repeatedly said location signal, wherein said receiving repeatedly said location signal is repeated at a first sampling rate;
said receiving repeatedly said gyro signal, wherein said receiving repeatedly said gyro signal is repeated at a second sampling rate, wherein said second sampling rate is higher than said first sampling rate.

6. The autonomous flight safety system of claim 1 further comprising:
said autonomous flight termination unit, wherein said autonomous flight termination unit is adapted to perform the following steps:
said receiving repeatedly said location signal, wherein said receiving repeatedly said location signal is repeated at a first sampling rate;
said receiving repeatedly said gyro signal, wherein said receiving repeatedly said gyro signal is repeated at a second sampling rate, wherein said second sampling rate is lower than said first sampling rate.

7. The autonomous flight safety system of claim 1 further comprising:
said autonomous flight termination unit, wherein said autonomous flight termination unit is adapted to perform the following steps:
said receiving repeatedly said location signal, wherein said receiving repeatedly said location signal is repeated at a first sampling rate;
said receiving repeatedly said gyro signal, wherein said receiving repeatedly said gyro signal is repeated at a second sampling rate, wherein said second sampling rate is equal to said first sampling rate.

8. The autonomous flight safety system of claim 1 further comprising: said autonomous flight termination unit adapted to perform the following steps:
said determining, repeatedly, using at least the gyro signal as input to an algorithm including pre-determined mission rules governing expected launch vehicle behavior, whether the launch vehicle is in an unstable condition;
said algorithm including comparing repeatedly the pitch rate and yaw rate indicated by the gyro signal with said maximum prescribed pitch rate and yaw rate, wherein the pitch rate and yaw rate indicated by the gyro signal comprise a separate pitch value and a separate yaw value, wherein said maximum prescribed pitch rate and yaw rate comprises a separate maximum pitch value and a separate maximum yaw value, and wherein said comparing repeatedly the pitch rate and yaw rate indicated by the gyro signal with said maximum prescribed pitch rate and yaw rate comprises:
comparing said separate pitch value to said separate maximum pitch value; and
comparing said separate yaw value to said separate maximum yaw value.

9. The autonomous flight safety system of claim 1 further comprising:
said autonomous flight termination unit adapted to perform the following steps:
said determining, repeatedly, using at least the gyro signal as input to an algorithm including pre-determined mission rules governing expected launch vehicle behavior, whether the launch vehicle is in an unstable condition;
said algorithm including comparing repeatedly the pitch rate and yaw rate indicated by the gyro signal with said maximum prescribed pitch rate and yaw rate, wherein the pitch rate and yaw rate indicated by the gyro signal comprise a combined pitch rate and yaw rate value, wherein said maximum prescribed pitch rate and yaw rate comprises a combined maximum pitch rate and yaw rate value, and wherein said comparing repeatedly the pitch rate and yaw rate indicated by the gyro signal with said maximum prescribed pitch rate and yaw rate comprises:
comparing said combined pitch rate and yaw rate value to said combined maximum pitch rate and yaw rate value.

10. The autonomous flight safety system of claim 1 further comprising:
a first circuit card assembly including said processor;
a second circuit card assembly including an input and an output interface circuit; and
a third circuit card assembly including a power conditioning circuit.

11. The autonomous flight safety system of claim 10 further comprising:
a fourth circuit card assembly including a connector and a connector circuit.

12. The autonomous flight safety system of claim 1 further comprising:
a first circuit card assembly including said processor and said position sensing system.

13. The autonomous flight safety system of claim 12 further comprising:
a second circuit card assembly including an input and an output interface circuit; and
a third circuit card assembly including a power conditioning circuit.

14. The autonomous flight safety system of claim 12 further comprising:
a fourth circuit card assembly including a connector and a connector circuit.

15. The autonomous flight safety system of claim 12 , wherein said software comprises:
a mission data load file comprising rules for vehicle position, velocity and time; and termination logic, wherein the ter

Assignees

• General Atomics

Inventors

• Beard Gary C
• Aven Kyle
• Anderson Rusty
• Helms Keith
• Xerri Jason
• Odom Jr Luther E

Classifications

• B64G1/002

  Launch systems · CPC title

• G08G5/30

  Flight plan management · CPC title

• G08G5/55 Primary

  for a single aircraft · CPC title

• G05D1/81

  Handing over between on-board automatic and on-board manual control · CPC title

• G05D1/495

  to ensure stability · CPC title