초록 ▼

A zero-momentum spacecraft\s attitude is controlled by determining the torque required about a control axis to maintain the desired attitude, and, during each of recurrent control cycles, enabling a magnetic torquer if the torque demand exceeds a threshold. During each of the control cycles, thruste

A zero-momentum spacecraft\s attitude is controlled by determining the torque required about a control axis to maintain the desired attitude, and, during each of recurrent control cycles, enabling a magnetic torquer if the torque demand exceeds a threshold. During each of the control cycles, thruster(s) are enabled to make up the difference between the torque demand and the estimated torque produced by the magnetic torquer. In determining the torque demand, the attitude rate signal is low-pass filtered to reduce noise, and the control loop bandwidth is maintained by totalling the estimated torque applied by the magnetic torquer and thrusters, integrating and high-pass filtering the estimated torque signals, and adding the filtered estimated torque with the filtered attitude rate signals to generate low-noise attitude rate signals. A three-axis system is described.

대표청구항 ▼

An attitude control system for a zero-momentum spacecraft which includes a body, for maintaining said body in a particular attitude, said system comprising: magnetic torquing means mounted on said body, for, when enabled, torquing said body about a particular axis; thrusters mounted on said body, fo

An attitude control system for a zero-momentum spacecraft which includes a body, for maintaining said body in a particular attitude, said system comprising: magnetic torquing means mounted on said body, for, when enabled, torquing said body about a particular axis; thrusters mounted on said body, for, when enabled, producing torque about said particular axis; a source of attitude command signals representing said particular attitude; attitude sensing means, for sensing the attitude of said spacecraft body about said particular axis, and for generating attitude-representative signals representing said attitude; attitude error processing means coupled to said attitude sensing means and to said source of attitude command signals, for determining, during each of a plurality of recurrent control intervals, the amount of torque required about said particular axis for tending to maintain said particular attitude; distribution means coupled to said attitude error processing means, to said magnetic torquing means, and to said thrusters, for, during each of said control intervals, energizing said magnetic torquing means in response to said torque required, and for, during each of said recurrent control intervals, if said torque required is greater than the torque which said magnetic torquing means provides, enabling at least one of said thrusters for generating torque representative of the difference between said torque required and the torque which said magnetic torquing means supplies.