Attitude stabilization of synchronous communications satellites employing narrow-beam antennas

Dougherty, H.; Lebsock, Kenneth L.; Rodden, J.

doi:10.2514/6.1970-457

Cited by 6 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The control law for the roll/yaw thrusters as found in Refs. 7,8,9 is: which results in the transfer function This equation is based on the condition that for complete damping of the orbital mode and rapid yaw response, the offset angle of the thruster Rootlocus for the above transfer function is shown in Fig. 3.…”

Section: Control Systems Descriptionmentioning

confidence: 99%

Comparison of different attitude control schemes for large communications satellites

Singh

Agrawal

Gran

1987

Guidance, Navigation and Control Conference

View full text Add to dashboard Cite

A comparative study of the robustness of various spacecraft body attitude control systems with structural flexibility is presented in this paper. The control systems examined are: (a) 3-Reaction Wheels (b) Body-fixed momentum wheel with offset thrusters (c) Skewed body-fixed momentum wheels with offset thrusters and (d) Body-fixed momentum wheel with two reaction wheels. For the size of large spacecraft considered in this paper, all these systems are shown to result in satisfactory performance. In order to exhibit their relative merits, the presence of severe structural interaction had to be introduced. Comparison was then made in terms of stability, which is affected by non-colocation of actuators and sensors. Performance borne out of the nonlinear simulation with both the large flexible spacecraft and dummy unstable interacting low structural mode is illustrated. This latter study shows that a system with single body-fixed momentum ?heel along pitch axis and two reaction wheels oriented along roll and yaw axes, is the most robust.

show abstract

Section: Control Systems Descriptionmentioning

confidence: 99%

Comparison of different attitude control schemes for large communications satellites

Singh

Agrawal

Gran

1987

Guidance, Navigation and Control Conference

View full text Add to dashboard Cite

show abstract

“…Taking A r >0, the conditions for stability require that the WHECON angle lies in the range 0<a<cos~1 (- (7) For the special case of critically damped roots, the momentum gain becomes K=2/(l-cosa) and the critically damped natural frequency of the controlled body is…”

Section: S -mentioning

confidence: 99%

“…Previous magnetic desaturation systems have used deadband, on-off, or proportional type controllers operating on the roll attitude error signal and/or the wheel tachometer signals. 7 The advent of reliable space qualified microprocessors makes possible the application of observer theory to the design of more efficient and accurate magnetic desaturation systems. This paper describes a simple threestate observer that provides remarkably accurate estimates of the yaw attitude and the roll and yaw environmental torques.…”

Section: Introductionmentioning

confidence: 99%

Magnetic desaturation of a momentum bias system

Lebsock

1983

Journal of Guidance, Control, and Dynamics

View full text Add to dashboard Cite

A simple observer and controller has been formulated for a low bandwidth yaw attitude control loop on a synchronous orbit momentum bias spacecraft. Operation of the system is entirely autonomous, with the only external reference required being a measurement of the spacecraft roll attitude. Low-level torque actuation is provided by a single magnetic coil that is mounted in the spacecraft body at an arbitrary orientation in the roll/yaw plane. This control system design provides much better pointing accuracy and rate stability for a given bias momentum than previous techniques. Simulated performance during a magnetic storm is presented for a Vee-Wheel momentum bias configuration. The properties of the geomagnetic field at synchronous altitude that are pertinent to spacecraft attitude control system design are described in the Appendix.

show abstract

Double gimballed reaction wheel attitude control system for high altitude communications satellites

Lebsock

Lyons

Scott

1971

Guidance, Control and Flight Mechanics Conference

View full text Add to dashboard Cite

Attitude stabilization of synchronous communications satellites employing narrow-beam antennas

Cited by 6 publications

References 0 publications

Comparison of different attitude control schemes for large communications satellites

Comparison of different attitude control schemes for large communications satellites

Magnetic desaturation of a momentum bias system

Double gimballed reaction wheel attitude control system for high altitude communications satellites

Contact Info

Product

Resources

About