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In this paper, the mechanism for the fault estimation (FE) problem for a steer-by-wire (SBW) vehicle with sensor and actuator faults is investigated. To deal with the design issues, we transformed the nonlinear model of SBW vehicle into a new coordinate system to jointly estimate the sensor and actuator faults. In the new coordinate system, the Lipschitz conditions and system uncertainties are also considered. The proposed schemes essentially transform the original system into two subsystems, where subsystem-1 includes the effects of actuator faults but is free from sensor faults and subsystem-2 only has sensor faults. Then two sliding mode observers (SMOs) are designed to estimate actuator and sensor faults, respectively. The sufficient conditions for the existence of the proposed observers with FI°o performance are derived and expressed as an LMI optimization problem such that the upper bounds of the state and fault estimation errors can be minimized. Finally, the numerical example with simulation results is provided to validate the practicability and efficacy of the developed estimation strategy

H control theory has achieved a very high level, which is not followed by appropriate applications in industry. Some reasons are: synthesis of H controllers is complex and based on the numerical Nevanlinna-Pick procedure, high order of controllers (higher than the order of the process) and sensitivity to deviation of controller coefficients (fragile controller). On the other hand, PI (PID) controllers are still dominant in industry, which places the problem of design of fixed structure controllers at the forefront. The mentioned problem is very difficult. This paper proposes a simple interactive procedure for design of H PI controllers with the presence of constraints (given the relative stability) based on Ddecomposition. The catalogue of responses to references, suppression of disturbances and minimum of H criteria of control is created. Selection of controllers, based on the catalogue, is left to the user. The application of H PI controllers to a CSTR (continuous stirred-tank reactor) is demonstrated.