Robust singularity avoidance in satellite attitude control
AssigneeHoneywell Inc.
InventorsBong Wie, David A. Bailey, Christopher J. Heiberg
Life of this patent
Estimating the term…
Abstract
Control moment gyros in an array are rotated to reorient a satellite. A pseudo inverse control is employed that adds a term to a Moore-Penrose pseudo inverse to prevent a singularity.
Claims6
A satellite attitude control comprising a plurality of control moment gyros in an array and a controller for changing a gimbal angle on each gyro, characterized in that the controller comprises signal processing means comprising:
- means for receiving a desired satellite attitude signal;
- means for producing an actual satellite attitude signal;
- means for producing an attitude error signal from desired satellite attitude signal and the actual satellite attitude signal;
- means for producing a torque command signal in response to the attitude error signal;
- means for producing an angular rate signal for each gyro using a pseudo inverse control law that uses said torque command signal and a Jacobean value for the angle of the a gyro, said pseudo inverse including a term that prevents a singularity in the angular rate signal;
- and
- means for rotating a gyro in the array in response to the angular rate signal.
A robotic system characterized by a plurality of actuators controlled by a signal processor according to a control law to control an element, characterized in that the signal process comprises:
- means for producing an error signal representing the difference between a desired and actual position for the element;
- means for producing a rate signal manifesting a desired rate of change in the position of the actuators in response to said error signal;
- means for producing a signal that controls the rate of actuator movement by each actuator using a pseudo inverse control law that uses said torque command signal and a Jacobean value for the angle of the actuator, said pseudo inverse including a term that prevents a singularity in the angular rate signal.
Dependencies are inferred from the claim text.