Attitude control for small satellites using control moment gyros

The stability and singularity problem of agile small satellite (ASS) with actuator failure is discussed in this paper. Firstly, the three-axis stabilized controller of an ASS is designed, where micro control moment gyros (MCMG's) in pyramid configuration (PC) is used as the actuator. By using the same controller and steering law, the control results before and after one gyro fails are compared by simulation. The variation of singular momentum envelope before and after one gyro fails is also compared. The simulation results show that the failure intensively decreases the capacity of output torque, which leads to the emergence of more singular points and the rapid saturation of MCMG's. Finally, the parameters of system controller are changed to compare the control effect.

show abstract

“…The simulation results have been shown as follows. The parameters of some small satellite are chosen as [9]: …”

Section: Comparison Of Simulation Results Of the System With Normal Amentioning

confidence: 99%

Attitude control for part actuator failure of agile small satellite

2008

View full text Add to dashboard Cite

show abstract

“…Thus, CMGs were born from this tiny disturbance torque. Ever since, CMGs have been used for key spacecraft programs, including Skylab, the Hubble Space Telescope, and the ISS [13,63]. Primarily, though, these devices have been used for medium to heavy/large satellites [13].…”

Section: Cmgs/vscmgsmentioning

confidence: 99%

Combines Attitude Control and Energy Storage for Small Satellites using Variable Speed Control Moment Gyroscopes

Lappas¹

2008

View full text Add to dashboard Cite

Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information SPONSOR/MONITOR'S ACRONYM(S) 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)EOARD Unit 4515 BOX 14 APO AE 09421 SPONSOR/MONITOR'S REPORT NUMBER(S)Grant 05-3037 DISTRIBUTION/AVAILABILITY STATEMENTApproved for public release; distribution is unlimited. SUPPLEMENTARY NOTES ABSTRACTThis report results from a contract tasking University of Surrey as follows: The Grantee will investigate three areas concerning energy storage and attitude control systems (ESACS) for small satellites: a.) Use of small satellite reference models to determine the relative scales for a combined variable speed control moment gyroscope (VSCMG) energy storage (ES) system. b.) Explore potential imbalances, derive mathematical descriptions of ESACS-imbalance systems and model the ESACS system in MATLAB/Simulink.. c.) Construct experimental hardware for power conversion demonstration: An experimental VSCMG system will be used to demonstrate combined attitude control and energy storage. The imbalances modeled in (b.) will be replicated in the experimental hardware. Derived control solutions to the imbalance problem will be implemented and validated in the experimental hardware. SUBJECT TERMS Government DisclaimerThe views expressed in this article are those of the authors and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the U.S. Government. AcknowledgementsThe ii Summary This work presents the first known energy storage and attitude control subsystem (ESACS) for small satellites, proving this technology to be viable, applicable to more complex, demanding space missions, and laden with substantial benefits, such as agile slewing, robust singularity avoidance, increased lifetime, mass savings, and favourable peak power density. In capturing the key features of this novel system, it investigates the design sizing, feasibility, mission utility, experimentation, and performance benefits for using variable-speed control moment gyroscopes (VSCMGs) to store and drain energy while controlling satellite orientation.First, a novel optimal ESACS sizing algorithm is developed for a practical, miniature spotlight synthetic aperture RADAR (SAR) space mission. When given a set of small satellite agility and energy storage requirements, the design is cast as a constrained nonlinear programming problem using a performance index constructed from subsystem design margins including the attitude torque, peak power, energy capacity, and subsystem mass margins and solved using a reduced-o...

show abstract

“…1) However, the attitude motion of such small satellites is more susceptible to external disturbances than their larger counterparts. Measurement noise, parametric uncertainty and control actuator restriction also have a large impact on control performance.…”

Section: Introductionmentioning

confidence: 99%

Robust Attitude Control and Compensation under Actuator Practical Restrictions

Meng¹,

Matunaga

2011

Trans. Japan Soc. Aero. S Sci.

View full text Add to dashboard Cite

Rapid attitude maneuvering and high pointing accuracy are two keywords for advanced missions of next generation satellites. The single-gimbal control moment gyro (CMG) is regarded as an ideal torque generator for rapid maneuvering due to its torque amplification capability. However, singularities, unknown friction effects and its real steering resolution constrain its practical performance. This paper presents a robust attitude control approach based on variable-structure theory with a time-varying sliding surface. This approach guarantees minimum angular path maneuvering, global stability and asymptotic convergence in the presence of CMG practical restrictions, inertial uncertainties and various disturbances. By taking CMG gimbal friction as unmodeled disturbances, the approach is independent of the gimbal friction model. Furthermore, a magnetic compensation method with gimbal rate feedback is proposed to reduce torque-generated error caused by the CMG steering mechanism including singularity avoidance logic and steering resolution limits. This method also attenuates the frequent switching operation of the CMG during the stabilization phase. Numerical simulations demonstrate the validity and feasibility of the proposed approach. It is also shown that the magnetic compensation method does not only improve the tracking accuracy effectively, but also reduces the total power consumption, which is very desirable in practice.

show abstract

Attitude control for small satellites using control moment gyros

Cited by 89 publications

References 5 publications

Attitude control for part actuator failure of agile small satellite

Attitude control for part actuator failure of agile small satellite

Combines Attitude Control and Energy Storage for Small Satellites using Variable Speed Control Moment Gyroscopes

Robust Attitude Control and Compensation under Actuator Practical Restrictions

Contact Info

Product

Resources

About