The practical design approach of robust control of multivariable systems

A nonlinear robust control design approach is presented in this paper for a prototype reusable launch vehicle (RLV) during the critical re-entry phase where the margin for error is small. A nominal control is designed following the dynamic inversion philosophy for the reaction control system (RCS) and optimal dynamic inversion philosophy for the aerodynamic control actuation. This nominal controller is augmented next with a barrier Lyapunov function based neuro-adaptive control in the inner loop, which enforces the body rates of the actual system i.e. in presence of uncertainties to track the closed-loop body rates of the nominal plant. A fusion logic is also presented for fusing the RCS and aerodynamic control. The control design approach presented here assures robust tracking of the guidance commands despite the presence of uncertainties in the plant model. Extensive nonlinear six degree-of-freedom (DoF) simulation study, which embeds additional practical constraints such as actuator delay in the aerodynamic control actuation and constraints related to the RCS, shows that the proposed design approach has both good command following as well as robustness characteristics.

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Robust control of multivariable systems by PID+Q controller

Proceedings of the 1997 American Control Conference (Cat. No.97CH36041) ◽

10.1109/acc.1997.609512 ◽

1997 ◽

Cited By ~ 1

Author(s):

T. Matsuo ◽

K. Nakano

Keyword(s):

Robust Control ◽

Multivariable Systems

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Design Limits for Buckling in the Creep Range

ASME 2010 Pressure Vessels and Piping Conference: Volume 3 ◽

10.1115/pvp2010-25091 ◽

2010 ◽

Cited By ~ 1

Author(s):

Maan Jawad ◽

Donald Griffin

Keyword(s):

Cylindrical Shells ◽

Time Dependent ◽

Design Approach ◽

Stress Strain ◽

Buckling Stress ◽

Creep Buckling ◽

Practical Design ◽

Slender Columns

A methodology is introduced for calculating the allowable buckling stress in equipment operating in the time-dependent (creep) range. Norton’s equation coupled with various procedures such as the stationary stress method, classical creep buckling equations, and the isochronous stress-strain diagrams are utilized to obtain a practical design approach for equipment operating in the time-dependent range. Various components are investigated such as slender columns, cylindrical shells, spherical components, and conical transition sections.

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Design Limits for Buckling in the Creep Range

Journal of Pressure Vessel Technology ◽

10.1115/1.4007031 ◽

2012 ◽

Vol 134 (6) ◽

Cited By ~ 2

Author(s):

Maan Jawad ◽

Donald Griffin

Keyword(s):

Cylindrical Shells ◽

Time Dependent ◽

Design Approach ◽

Stress Strain ◽

Buckling Stress ◽

Creep Buckling ◽

Practical Design ◽

Slender Columns

A methodology is introduced for calculating the allowable buckling stress in equipment operating in the time-dependent (creep) range. Norton's equation coupled with various procedures such as the stationary stress method, classical creep buckling equations, and the isochronous stress–strain diagrams are utilized to obtain a practical design approach for equipment operating in the time-dependent range. Various components are investigated such as slender columns, cylindrical shells, spherical components, and conical transition sections.

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