Momentum position control

• US 6,241,194 B1
• Filed: 06/28/1999
• Issued: 06/05/2001
• Est. Priority Date: 06/28/1999
• Status: Expired due to Term

• Current Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Heiberg, Christopher J.
• Primary Examiner(s): Barefoot, Galen L.
• Application Number:
  US09/340,806
• Time in Patent Office: 708 Days
• Field of Search: 244/164, 244/165, 244/171, 244/170, 701/13
• US Class Current: 244/165
• CPC Class Codes: B64G 1/244 Spacecraft control systems
• CPC Class Codes: B64G 1/283 using reaction wheels
• CPC Class Codes: B64G 1/286 using control momentum gyroscopes (CMGs)
• CPC Class Codes: B64G 1/36 using sensors, e.g. sun-sensors, horizon sensors

Abstract

A vehicle control system is disclosed utilizing a reaction wheel assembly for producing small scanning motions and, in combination, a scissored pair of low-cost control moment gyros is used to produce larger slewing motions.

Claims

1. A control system for a vehicle comprising:

a reaction wheel array operable to provide a limited scanning motion for the vehicle on a plurality of planes; and

a scissored pair of control moment gyros each having a spin axis limited to a single plane and an angular momentum; and

means to rotate the spin axes of the scissored pair to cause the momentum vectors to change direction and act in opposite directions, the same direction and directions therebetween according to the amount of rotation of the spin axes to slew the vehicle.

2. Apparatus according to claim 1 wherein the scissored pair is used to create a large torque to achieve a rapid slew reorientation of the vehicle between scans.

3. Apparatus according to claim 2 wherein the scanning motion produce by the reaction wheel array is assisted by the momentum produced by the scissored pair.

4. Apparatus according to claim 2 wherein the scissored pair produces a disturbance and the reaction wheel assembly is used to mitigate the disturbance.

6. Apparatus according to claim 1 where in the vehicle is a satellite and the scanning motion is for observing terrestrial targets.

7. Apparatus according to claim 6 wherein the scanning motion for the satellite is produced for use by a radar antenna.

5. Where the number of CMGs in a scissored pair is more than 1 and are used in conjunction to produce torque and momentum in a plane.

8. A control system for a vehicle comprising:

a reaction wheel array operable to provide a limited scanning motion for the vehicle on a plurality of planes; and

a scissored pair of control moment gyros each having a spin axis and an angular momentum, momentum vectors of said gyros lying substantially in a plane; and

means to rotate the spin axes of the scissored pair to cause the momentum vectors to change direction and act in opposite directions, the same direction and directions therebetween according to the amount of rotation of the sp,in axes to slew the vehicle;

wherein the momentum vectors of the scissored pair lie substantially in a plane.

9. The method of controlling a satellite and a scanning device thereon comprising the steps of:

A. causing a scanning motion of the scanning device by use of a reaction wheel assembly; and

B. causing a slewing motion of the satellite in one plane by use of at least one scissored pair of control moment gyros.

10. The method of claim 9 including the step of:

C. using at least one scissored pair of control moment gyros to assist the reaction wheel assembly produce the scanning motion.

11. The method of claim 9 including the step of:

C. using the reaction wheel assembly to mitigate any disturbance produced by at least one scissored pair.