Control moment gyroscope array and method of power distribution therefor

• US 20100044517A1
• Filed: 04/18/2007
• Published: 02/25/2010
• Est. Priority Date: 04/18/2007
• Status: Active Grant

• Current Assignee: Ithaco Space Systems, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Ithaco Space Systems, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Stromswold, Eric, Bialke, William E.
• Granted Patent: US 8,210,062 B2
• Time in Patent Office: Days
• US Class Current: 244/165
• CPC Class Codes: B64G 1/286 using control momentum gyroscopes (CMGs)
• CPC Class Codes: Y10T 74/1218 Combined
• CPC Class Codes: Y10T 74/1229 Gyroscope control
• CPC Class Codes: Y10T 74/1254 by motor torque

Abstract

An attitude control system for a spacecraft is disclosed that includes a scissored pair of control moment gyroscopes for delivering an output torque to the spacecraft along a an output axis, wherein each gyroscope has a spin motor for spinning a rotor about a rotor axis and a gimbal torque motor for rotating the rotor about a gimbal axis, and wherein the system includes a generator for extracting kinetic energy from the rotors during rotor deceleration to power the gimbal torque motors of the gyroscopes.

Claims

1. A directional control array for a spacecraft comprising:

a) a first control moment gyroscope having a first rotor, a spin motor to spin the first rotor about a first rotor axis, and a first gimbal motor to rotate the first rotor about a first gimbal axis that is normal to the first rotor axis;

b) a second control moment gyroscope having a second rotor, a spin motor to spin the second rotor about a second rotor axis, a second gimbal motor to rotate the second rotor about a second gimbal axis that is normal to the second rotor axis;

c) means for extracting kinetic energy from the first rotor as the first rotor is decelerated to power the first gimbal motor; and

d) means for extracting kinetic energy from the second rotor as the second rotor is decelerated to power the second gimbal motor.

2. A directional control array as recited in claim 1, wherein the first and second control moment gyroscopes have parallel gimbal axes.

3. A directional control array as recited in claim 1, further comprising means for controlling gimbal angle and gimbal rate of the first and second gimbal motors.

4. A directional control array as recited in claim 1, wherein energy extracted from the first rotor is delivered to a first gimbal motor driver.

5. A directional control array as recited in claim 1, wherein energy extracted from the second rotor is delivered to a second gimbal motor driver.

6. An attitude control system for a spacecraft comprising:

a) a first scissored pair of control moment gyroscopes for delivering an output torque to a spacecraft along a first output axis, wherein each gyroscope of the first scissored pair has a spin motor for spinning a rotor about a rotor axis and a gimbal motor for rotating the rotor about a gimbal axis that is normal to the rotor axis and the first output axis, the first scissored pair having means for extracting kinetic energy from the rotors of the first scissored pair as those rotors are decelerated to power the gimbal motors of the first scissored pair;

b) a second scissored pair of control moment gyroscopes for delivering an output torque to a spacecraft along a second output axis, wherein each gyroscope in the second scissored pair has a spin motor for spinning a rotor about a rotor axis and a gimbal motor for rotating the rotor about a gimbal axis that is normal to the rotor axis and to the second output axis, the second scissored pair having means for extracting kinetic energy from the rotors of the second scissored pair as those rotors are decelerated to power the gimbal motors of the second scissored pair; and

c) a third scissored pair of control moment gyroscopes for delivering an output torque to a spacecraft along a third output axis, wherein each gyroscope in the third scissored pair has a spin motor for spinning a rotor about a rotor axis and a gimbal motor for rotating the rotor about a gimbal axis that is normal to the rotor axis and to the third output axis, the third scissored pair having means for extracting kinetic energy from the rotors of the third scissored pair as those rotors are decelerated to power the gimbal motors of the third scissored pair.

7. An attitude control system as recited in claim 6, further comprising means for controlling gimbal angle and precession rate of the gimbal torque motors of the first, second and third scissored pairs.

8. A method of powering a control moment gyroscope comprising the steps of:

a) accelerating a rotor to a nominal speed;

b) decelerating the rotor;

c) extracting energy from the decelerating rotor; and

d) powering a gimbal motor with the extracted energy.

9. A method according to claim 8, further comprising the step of rotating the rotor at a desired gimbal rate to a desired gimbal angle.

10. A method according to claim 8, further comprising the step of returning the rotor to the nominal speed.

11. A method of powering a scissored pair of control moment gyroscopes comprising the steps of:

a) accelerating the rotors of the scissored pair to a nominal speed;

b) simultaneously decelerating the rotors of the scissored pair;

c) extracting energy from the decelerating rotors; and

d) powering the gimbal torque motors of the scissored pair with the energy extracted from the decelerating rotors.

12. A method according to claim 11, further comprising the step of rotating the rotors in tandem at a desired gimbal rate to desired gimbal angles.

13. A method according to claim 12, further comprising the step of returning the rotors of the scissored pair to a nominal speed.

14. A method according to claim 13, wherein the rotors of the scissored pair return to a nominal speed as the gimbal torque motors of the scissored pair precess the rotors at a desired gimbal rate.

15. A method according to claim 14, further comprising the step of controlling the rate at which the gimbal torque motors of the scissored pair precess such that the scissored pair has zero output torque.