Robust disturbance decoupling with simultaneous exact model matching via static measurement output feedback

The problem of robust exact model matching with simultaneous robust disturbance decoupling for linear systems with nonlinear uncertain structure (NLUS) and with measurable and non measurable disturbances is solved via an independent of the uncertainties static measurement output feedback law. The necessary and sufficient conditions for the problem to have a solution, are established. The general analytical expressions of the feedback matrices are derived

Robust triangular decoupling with application to 4WS cars

The necessary and sufficient conditions for the problem of robust triangular decoupling (RTD) are established for the case of a linear time-invariant system with a nonlinear uncertain structure. The general analytic expressions of the feedback matrices and the robust triangularly decoupled closed-loop system are derived. For the solution of the problem of robust triangular decoupling with simultaneous Hurwitz invariability, sufficient conditions are established. Finally, all of the above results are successfully applied to control four-wheel steering (4WS) cars

Robust input-output decoupling via static measurement output feedback

In this paper the problem of robust input-output decoupling for linear systems with nonlinear uncertain structure (NLUS), via an independent from the uncertainties static measurement output feedback law, is studied. The necessary and sufficient conditions for the problem to have a solution, are established. The general analytical expressions of the feedback matrices and the decoupled closed loop system are derived. The problem of robust input - output decoupling with simultaneous Hurwitz invariability, is also studied

Output feedback decoupling of linear systems with nonlinear uncertain structure

The problem of input-output decoupling for linear systems with nonlinear uncertain structure, via an independent of the uncertainties static output feedback law, is solved. The necessary and sufficient conditions for the problem have a solution are established. The general analytical expressions of the feedback matrices and the decoupled closed loop system, are derived. Copyright (C) 1996 Published by Elsevier Science Lt

Robust disturbance rejection for left-invertible linear systems with nonlinear-uncertain structure

The problem of robust disturbance rejection for left invertible linear systems, with nonlinear uncertain structure and with measurable and nonmeasurable disturbances, is solved via an independent from the uncertainties static measurement output feedback law. The necessary and sufficient conditions for the problem to have a solution are established. The general explicit expression of the measurement output feedback matrix and the measurement disturbances feedback matrix are derived The feedback invariant poles are determined. Sufficient conditions for robust disturbance rejection with simultaneous robust stability are also established. The rejection of the influence of the rotary gust disturbing the vertical I velocity of the longitudinal motion of an aircraft is achieved

Robust triangular decoupling with simultaneous robust disturbance rejection

For the case of a linear time invariant system with nonlinear uncertain structure the problem of robust triangular decoupling with simultaneous robust disturbance rejection (RTDRDR) is studied. The necessary and sufficient conditions for the solution of the RTDRDR problem are established. The general expressions for the feedback matrices solving the problem are derived in analytic form. The resulting closed-loop system, being triangularly decoupled and having no influence from the disturbances to the output, is analytically determined. For the solution of the RTDRDR problem with simultaneous robust stability, sufficient conditions are established. The present results are successfully applied to control a vertical take-off and landing aircraft in hover

Automatic steering control of unmanned vehicles

The problem of robust automatic steering of an autonomous unmanned vehicle is studied. The problem is solved using a robust P-D feedback controller feeding back the path error and the front steering angle. The design goal is to follow accurately a desired path independently from the presence of a possible disturbances (wind forces acting on the aerodynamic center of the side surface of the vehicle) and uncertainties (road, mass and velocity uncertainties). Additionally robust stability of all system variables is required. It is proven that the design requirements can always be satisfied via appropriate P-D feedback. The present results appear to be beneficially for worksite and agriculture vehicles. The results are illustrated via simulation for the path of a tractor during tilling

Controller design for lateral manoeuvres in electromagnetic wind tunnels

The roll angle, the yaw angle and the side-slip position of test aircrafts in electromagnetic wind tunnels, are independently controlled. The problem is proven to be always solvable by applying a static state feedback law involving aerodynamic and electromagnetic variables. The general forms of the static controllers, solving the problem, as well as the resulting closed loop system, are derived. The stability of the closed loop is guaranteed

Robust exact model matching via P-D feedback with application to DC servo motor

The problem of exact model matching for single input single output linear systems with nonlinear uncertain structure, via an independent of the uncertainties P-D state and output feedback, is studied. The necessary and sufficient conditions for the problem to have a solution, are established. The general expressions of the feedback matrices solving the problem are derived. For the special case of static state feedback, the respective results are also derived. For a permanent magnet DC motor with uncertain load inertia and viscosity, an independent of the uncertainties P-D feedback law is applied to yield a closed loop system transfer function which is equal to that of a desired model's

Static controllers for magnetic suspension and balance systems

For a test aircraft in a wind tunnel with magnetic suspension and balance systems, a decoupling control configuration is proposed. Using the input-output decoupling technique the flight variables are controlled independently at all frequencies and for all aerodynamic and electromagnetic conditions. The decoupling controllers are static. The performance of the resulting closed-loop system is quite satisfactory