Autonomous navigation, guidance and control using LDRI

• US 6,411,871 B1
• Filed: 08/06/2001
• Issued: 06/25/2002
• Est. Priority Date: 08/05/2000
• Status: Expired due to Term

• Current Assignee: American GNC Corporation
• Original Assignee: American GNC Corporation
• Inventors: Lin, Ching-Fang
• Primary Examiner(s): Camby, Richard M.
• Application Number:
  US09/924,226
• Publication Number:
  US 20020035419A1
• Time in Patent Office: 323 Days
• Field of Search: 701/27, 701/28, 701/4, 701/13, 356/5.01, 356/5.04
• US Class Current: 701/27
• CPC Class Codes: B64G 1/24 Guiding or controlling apparatus, e.g. for attitude control
• CPC Class Codes: B64G 1/244 Spacecraft control systems
• CPC Class Codes: B64G 1/247 Advanced control concepts for autonomous, robotic spacecraft, e.g. by using artificial intelligence, neural networks or autonomous agents
• CPC Class Codes: B64G 1/36 using sensors, e.g. sun-sensors, horizon sensors
• CPC Class Codes: B64G 1/66 Arrangements or adaptations of apparatus or instruments, not otherwise provided for
• CPC Class Codes: G01S 17/66 Tracking systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/89 for mapping or imaging

Abstract

An autonomous navigation, guidance, and control process for docking and formation flying by utilizing the laser dynamic range imager (LDRI) and key technologies, including fuzzy logic based guidance and control, optical flow calculation (including cross-correlation, phase-correlation, and image differential), software design and implementation, and verification methods. The autonomous navigation, guidance, and control process includes the steps of providing an expected reference position relative to a target; generating a carrier position and attitude relative to said target by a Range and Intensity Images Provider; producing a relative position and attitude error; and producing control commands from said relative position and attitude error for relative motion dynamics.

Claims

1. An autonomous navigation, guidance and control process, comprising the steps of

(a) providing an expected reference position relative to a target;

(b) generating a carrier position and attitude relative to said target by a Range and Intensity Images Provider;

(c) producing a relative position and attitude error; and

(d) producing control commands from said relative position and attitude error for relative motion dynamics.

2. An autonomous navigation, guidance and control process, as recited in claim 1, wherein said Range and Intensity Images Provider is a Laser Dynamic Range Imager (LDRI).

3. An autonomous navigation, guidance and control process, as recited in claim 2, wherein said expected reference position relative to said target is a trajectory and is provided by a reference relative position provider.

4. An autonomous navigation, guidance and control process, as recited in claim 2, wherein said expected reference position relative to said target is a number and is provided by a reference relative position provider.

5. An autonomous navigation, guidance and control process, as recited in claim 2, after the step (a), further comprising a step of smoothing said reference position relative to said target.

6. An autonomous navigation, guidance and control process, as recited in claim 3, after the step (a), further comprising a step of smoothing said reference position relative to said target.

7. An autonomous navigation, guidance and control process, as recited in claim 4, after the step (a), further comprising a step of smoothing said reference position relative to said target.

8. An autonomous navigation, guidance and control process, as recited in claim 3, wherein the step (d) further comprises the steps of:

(d.1) performing derivation on error variables to calculate error derivations; and

(d.2) collecting said error variables and said error derivatives to generate a control output.

9. An autonomous navigation, guidance and control process, as recited in claim 4, wherein the step (d) further comprises the steps of:

(d.1) performing derivation on error variables to calculate error derivations; and

(d.2) collecting said error variables and said error derivatives to generate a control output.

10. An autonomous navigation, guidance and control process, as recited in claim 6, wherein the step (d) further comprises the steps of:

(d.1) performing derivation on error variables to calculate error derivations; and

(d.2) collecting said error variables and said error derivatives to generate a control output.

11. An autonomous navigation, guidance and control process, as recited in claim 7, wherein the step (d) further comprises the steps of:

(d.1) performing derivation on error variables to calculate error derivations; and

(d.2) collecting said error variables and said error derivatives to generate a control output.

12. An autonomous navigation, guidance and control system, comprising:

a reference relative position provider which provides an expected reference position relative to a target;

a guidance and control system generating control commands;

an error calculation module for deriving a difference between a measured relative position and said reference relative position;

a range and intensity images provider producing range images and intensity images; and

a relative motion dynamics which receives said range images and intensity images for performing a control actuation.

13. An autonomous navigation, guidance and control system, as recited in claim 12, further comprising of a relative position shaping module for smoothing said reference relative position.

14. An autonomous navigation, guidance and control system, as recited in claim 12, wherein said range and intensity images provider is a Laser Dynamic Range Imager (LDRI).

15. An autonomous navigation, guidance and control system, as recited in claim 13, wherein said range and intensity images provider is a Laser Dynamic Range Imager (LDRI).