초록 ▼

An agile, spinning spacecraft has a first body portion and a second body portion which is rotatably coupled about a first rotational axis to the first body portion. A pair of planar solar cell arrays are rotatably coupled to the second body portion along a second rotational axis that is preferably o

An agile, spinning spacecraft has a first body portion and a second body portion which is rotatably coupled about a first rotational axis to the first body portion. A pair of planar solar cell arrays are rotatably coupled to the second body portion along a second rotational axis that is preferably orthogonal to the first rotational axis. The first body portion can be spun if desired and the first rotational axis can be directed by an attitude control system to have selected orientations. The solar cell arrays are rotated about the first and second rotational axes in accordance with steering laws which maintain the arrays in an orthogonal relationship with a Sun line.

대표청구항 ▼

[ We claim:] [1.] A method of positioning a spacecraft in a selected orientation while Sun-steering a solar cell array of said spacecraft as said spacecraft moves in an orbital plane about an Earth in which a Sun has an elevation angle .beta. from said orbital plane and said spacecraft has an angle

[ We claim:] [1.] A method of positioning a spacecraft in a selected orientation while Sun-steering a solar cell array of said spacecraft as said spacecraft moves in an orbital plane about an Earth in which a Sun has an elevation angle .beta. from said orbital plane and said spacecraft has an angle .eta. from midnight, comprising the steps of:spinning a body portion of said spacecraft to generate an angular momentum;spinning a momentum wheel of said spacecraft to reduce said angular momentum and enhance spacecraft agility;generating turning moments in said spacecraft to realize said selected orientation; andsteering said array about first and second mutually orthogonal spacecraft axes to direct said array at said Sun;wherein said selected orientation directs said first spacecraft axis at a subsatellite point and said steering step includes the steps of:rotating said array about said first axis in accordance with a steering angle A from said orbital plane wherein said steering angle A=ATAN2(sinA, cosA) in which ATAN2 is a four-quadrant solution of an arctangent function, sin A=sin.beta./{(sin.beta.).sup.2 +(cos.beta. sin.eta.).sup.2 }.sup.1/2 and cos A=(cos.beta. sin.eta.)/{(sin.beta.).sup.2 +(cos.beta. sin.eta.).sup.2 }.sup.1/2 ; androtating said array about said second axis in accordance with a steering angle B from said first spacecraft axis wherein said steering angle B=ATAN2(sinB, cosB) in which ATAN2 is a four-quadrant solution of an arctangent function, sin B={(sin.beta.).sup.2 +(cos.beta. sin.eta.).sup.2 }1/2 and cos B=cos.beta. cos.eta..