Synchronized autonomous docking system

• US 6,227,495 B1
• Filed: 12/10/1998
• Issued: 05/08/2001
• Est. Priority Date: 12/10/1998
• Status: Expired due to Fees

• Current Assignee: National Aeronautics and Space Administration (Government of the United States of America)
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Howard, Richard T., Book, Michael L., Bryan, Thomas C.
• Primary Examiner(s): Barefoot, Galen L.
• Application Number:
  US09/228,033
• Time in Patent Office: 880 Days
• Field of Search: 244/158 R, 244/159, 244/161, 358/103, 358/109, 358/107
• US Class Current: 244/172.4
• 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 1/36 using sensors, e.g. sun-sensors, horizon sensors
• CPC Class Codes: B64G 1/646 Docking or rendezvous systems refuelling in space B64G1/4024
• CPC Class Codes: G05D 1/0225 involving docking at a fixed facility, e.g. base station or loading bay parking aids B62D15/027
• CPC Class Codes: G05D 1/0234 using optical markers or beacons optical beacons per se G01S1/70

Abstract

A synchronized target subsystem for use in an automated docking system for docking a chase vehicle with a target vehicle wherein the chase vehicle is provided with a video camera for feeding digitized frames to an image processing unit which controls a timing circuit. The timing circuit turns on the video camera to digitize a foreground frame and at the same time turns on a transmitter on the chase vehicle. A power generating antenna on the target vehicle receives the transmitted signal from the transmitter and actuates lights on the chase vehicle so that these lights appear in the foreground frame. After the foreground frame has been grabbed, the timing circuit turns the transmitter off and signals the video camera to digitize a background frame. The image processing unit subtracts the background frame from the foreground frame and provides a docking signal.

Claims

1. A synchronized target subsystem for use in automated docking systems wherein a chase vehicle is docked with a target vehicle, said synchronized target subsystem comprising,

a. a video camera carried by the chase vehicle for digitizing background and foreground frames,

b. an image processing unit connected to the camera,

c. a transmitter carried by the chase vehicle for directing a signal toward the target vehicle when the transmitter is actuated,

d. a timing circuit connected to the image processing unit for actuating the video camera and the transmitter,

e. a plurality of lights carried by the target vehicle,

f. a receiving antenna carried by the target vehicle for generating power when the signal from the transmitter is received, and

g. a power conditioning unit connected between the antenna and the lights for conditioning the power from the antenna to a voltage suitable for operating the lights.

2. The synchronized target subsystem of claim 1 wherein the timing circuit actuates the transmitter to transmit a signal for a sufficient time to allow the video camera for to acquire a foreground frame, said timing circuit then turning off the transmitter and causing the video camera to acquire a background frame.

3. The system of claim 2 wherein the image processing unit subtracts the background frame from the foreground frame to provide a docking signal.

4. The subsystem of claim 3 wherein the lights comprise first and second lights mounted on a base plane and a third light mounted at the end of a post extending outwardly from the base plane.

5. A synchronized target subsystem for use in automated docking systems wherein a chase vehicle is docked with a target vehicle, said synchronized target subsystem comprising;

a plurality of light sources carried by the target vehicle for transmitting a plurality of light signals,

a single video camera carried by the chase vehicle for directly receiving said light signals from the target vehicle and for digitizing background and foreground frames based on said light signals,

an image processing unit, carried by the chase vehicle and connected to said video camera, for processing said background and foreground frames,

a transmitter carried by the chase vehicle for directing a control signal toward the target vehicle when said transmitter is actuated,

a timing circuit, carried by the chase vehicle and connected to the image processing unit, the video camera and the transmitter, for actuating the video camera and transmitter,

a receiving antenna carried by the target vehicle for generating power when the control signal from the transmitter is received, and

a power conditioning unit connected between the antenna and the light sources for conditioning the power from the antenna to a voltage suitable for operating the light sources.