초록 ▼

Methods and systems for stabilizing satellite spin about an intermediate inertia axis (Z) are disclosed. A set of gyros (22) sense the X component and the Y component of the angular velocity of the satellite body. A single degree of freedom momentum wheel (26) has a fixed transverse orientation with

Methods and systems for stabilizing satellite spin about an intermediate inertia axis (Z) are disclosed. A set of gyros (22) sense the X component and the Y component of the angular velocity of the satellite body. A single degree of freedom momentum wheel (26) has a fixed transverse orientation with respect to the intermediate axis in order to store momentum. In one embodiment, the momentum wheel (26) is oriented to store momentum parallel to the Y axis. A tachometer (30) senses the rotation rate of the momentum wheel (26). A processor (24) forms a control signal representative of a control torque to be applied to the momentum wheel (26). The control torque is based upon the X component and the Y component of angular velocity of the satellite, and the angular velocity of the momentum wheel (26). These methods and systems may also be used to invert the spin direction of spinning satellites, ensure tumble recover to a preferred orientation, and stabilize the body spin axis against nutation, dynamic imbalance and external torques.

대표청구항 ▼

A method of stabilizing the spin of a spinning satellite about an intermediate inertia axis, the method comprising the steps of: sensing a first component of the angular velocity of the satellite about a first axis transverse to the intermediate inertia axis; sensing a second component of the angula

A method of stabilizing the spin of a spinning satellite about an intermediate inertia axis, the method comprising the steps of: sensing a first component of the angular velocity of the satellite about a first axis transverse to the intermediate inertia axis; sensing a second component of the angular velocity of the satellite about a second axis transverse to the intermediate inertia axis, wherein the second axis is transverse to the first axis; sensing the angular velocity of not more than one single degree of freedom momentum wheel, wherein the momentum wheel has a fixed transverse orientation with respect to the intermediate inertia axis, wherein the fixed transverse orientation of the momentum wheel is offset from a principal axis of the satellite by an angle between 0 and 90 degrees; computing a commanded angular velocity for the momentum wheel in dependence upon the first component and the second component, wherein the commanded angular velocity is proportional to a transverse component of the angular velocity of the satellite, wherein the transverse component is in a direction based upon an eigenvector associated with an unstable eigenvalue of a linear dynamic model of the satellite; forming a control signal representative of a control torque to be applied to the momentum wheel, wherein the control torque is proportional to a difference between the angular velocity of the momentum wheel and the commanded angular velocity; and applying the control signal to the momentum wheel.