초록 ▼

A momentum actuator for steering a spacecraft is disclosed. The momentum actuator comprises a rotor, a gimbal upon which the rotor is mounted, and a stepper motor coupled to the gimbal and operable to rotate the rotor about the gimbal in a series of steps. In one embodiment of the present invention

A momentum actuator for steering a spacecraft is disclosed. The momentum actuator comprises a rotor, a gimbal upon which the rotor is mounted, and a stepper motor coupled to the gimbal and operable to rotate the rotor about the gimbal in a series of steps. In one embodiment of the present invention the spin rate of the rotor can be varied to provide torque.

대표청구항 ▼

I claim: 1. A method for steering control-moment gyroscopes having variable-speed rotors and moveable gimbals, the gimbals moving in discrete steps, the method comprising: generating a table referencing all momentum points in momentum space achievable by all possible alignments of the control-momen

I claim: 1. A method for steering control-moment gyroscopes having variable-speed rotors and moveable gimbals, the gimbals moving in discrete steps, the method comprising: generating a table referencing all momentum points in momentum space achievable by all possible alignments of the control-moment gyroscopes; determining a change in momentum needed to make a desired attitude change for a spacecraft; determining if the gimbals need to be stepped to provide at least part of the change in momentum; altering only a spin rate of the rotor if the change in momentum does not require the gimbals to be moved; and changing the alignment of the gimbals if needed to provide at least part of the change in momentum. 2. The method of claim 1 wherein the step of determining a change in momentum further comprises comparing each of the momentum points in the space of all momentum points achievable by an alignment of the control-moment gyroscopes that surround the current momentum point to determine if the control-moment gyroscope needs to be rotated. 3. A method for steering control-moment gyroscopes having variable-speed rotors and moveable gimbals, the gimbals moving in discrete steps, the method comprising: generating a table referencing all momentum points in momentum space achievable by all possible alignments of the control-moment gyroscopes, except any alignments of the control-moment gyroscopes that can result in a singular condition; determining a change in momentum needed to make a desired attitude change for a spacecraft; determining if the gimbals need to be stepped to provide at least part of the change in momentum; altering only a spin rate of the rotor if the change in momentum does not require the gimbals to be moved; and changing the alignment of the gimbals if needed to provide at least part of the change in momentum. 4. The method of claim 1 wherein the step of changing the alignment of the control-moment gyroscopes further comprises changing the spin rate of the rotor of the control-moment gyroscope after changing the alignment of the control-moment gyroscope to provide any additional momentum needed. 5. The method of claim 1 further comprising varying the spin rate of the rotors as the gimbals of the control-moment gyroscope are being moved. 6. The method of claim 1 wherein the step of changing the alignment of the control-moment gyroscopes further comprises; a) moving the control-moment gyroscopes to a new momentum point; b) changing the spin rate of the rotor: c) checking to determine if desired change in momentum has occurred; and d) repeating the steps of a-c if the desired momentum change is not finished. 7. The method of claim 6 further comprising the step of collecting data between the steps of moving the control-moment gyroscopes and changing the spin rate of the rotors.