Abstract A method for remotely determining the dynamic imbalance of and for changing the spin rate and center of gravity of a spinning spacecraft which utilizes the communications channel between the spacecraft and the receiving terminal, the master index pulse generator on the spacecraft, and the spacecraft axial thrusters. To measure the dynamic imbalance, the variation in the received signal strength is plotted relative to the master index pulse. The peak-to-peak variation in the received signal strength is proportional to twice the magnitude of the wobble angle of the spacecraft created by the dynamic imbalance. The phase of the wobble angle relative to the master index pulse (MIP) is proportional to the time interval between the occurrence of an MIP and either a peak or a trough in the received signal strength. To be able to change the spin rate, the spinning body must also include a means for dynamically balancing the spinning body. To change the spin rate, a dynamic imbalance of a known wobble angle and phase is introduced by the dynamic balancing means. An axial thruster is then fired for a predetermined time interval thereby coupling a portion of the axial thrust force into the rotational energy of the spinning body. To be able to change the center of gravity, the dynamic balance means must be of the type which comprises a plurality of axially movable masses. To change the center of gravity, the axially movable masses are moved in unison in either axial direction thereby shifting the center of gravity in that direction.
A method for determining the periodic wobble of a free spinning body, comprising the ordered steps of: radiating electromagnetic energy in a known pattern from said body; directing said radiated electromagnetic energy at a remotely located electromagnetic energy detector; detecting the magnitude of said radiated electromagnetic energy; and determining the peak-to-peak fluctuation of the detected magnitude of said radiated electromagnetic energy to yield a resultant which is proportional to the magnitude of said periodic wobble of said body.
Claim 2
Independent Claim
78 words
A method for determining the periodic wobble of a free spinning body, comprising the ordered steps of: radiating electromagnetic energy in a known pattern from said body; directing said radiated electromagnetic energy at a remotely located electromagnetic energy detector; detecting the magnitude of said radiated electromagnetic energy; and determining the peak-to-peak fluctuation of the detected magnitude of said radiated electromagnetic energy to yield a resultant which is proportional to the magnitude of said periodic wobble of said body.
Claim 3
Independent Claim
141 words
A method for determining the dynamic imbalance of a free spinning body comprising the ordered steps of: radiating electromagnetic energy in a known pattern from said spinning body; directing said radiated electromagnetic energy at a remotely located electromagnetic energy detector; detecting the magnitude of said radiated electromagnetic energy; determining the peak-to-peak fluctuation of the detected magnitude of said radiated electromagnetic energy to yield a resultant which is proportional to the magnitude of the dynamic imbalance of said spinning body; transmitting a pulse once each spin period of said spinning body from said spinning body to said remote location; and measuring the time interval between a peak of the magnitude of the detected electromagnetic energy and the occurrence of said pulse to yield a resultant which is proportional to the phase of the dynamic imbalance relative to the occurrence of said pulse.
Claim 4
Independent Claim
141 words
A method for determining the dynamic imbalance of a free spinning body comprising the ordered steps of: radiating electromagnetic energy in a known pattern from said spinning body; directing said radiated electromagnetic energy at a remotely located electromagnetic energy detector; detecting the magnitude of said radiated electromagnetic energy; determining the peak-to-peak fluctuation of the detected magnitude of said radiated electromagnetic energy to yield a resultant which is proportional to the magnitude of the dynamic imbalance of said spinning body; transmitting a pulse once each spin period of said spinning body from said spinning body to said remote location; and measuring the time interval between a peak of the magnitude of the detected electromagnetic energy and the occurrence of said pulse to yield a resultant which is proportional to the phase of the dynamic imbalance relative to the occurrence of said pulse.