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This paper addresses the position and attitude tracking control problem for a recently designed ellipsoidal airship with four vectored thrusters. External disturbances, thruster faults, mass matrix and aerodynamic coefficient uncertainties, which are inevitably encountered in practice, can deteriorate the control system performance of airship and even lead to system instability. To meet these challenges, we develop an adaptive integral sliding mode control method without requiring the prior knowledge of mass matrix and aerodynamic coefficients, in which these uncertainties and faults are considered simultaneously. We showed that the three Cartesian positions and three Euler attitude angles could globally asymptotically track the desired values in the face of external disturbances, thruster faults, mass matrix and aerodynamic coefficient uncertainties. Simulation results validate the effectiveness and advantage of proposed methods.

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This paper is concerned with the problem of robust H ∞ output tracking control for uncertain sampleddata systems with probabilistic actuator failures. By assuming that each actuator fault takes values randomly in a finite set, a new actuator-failure-mode is proposed. Lyapunov-Krasovskii functional combined with the input delay approach as well as the free-weighting matrix approach are employed to establish the H ∞ performance, and the controller design is cast into a convex optimization problem with linear matrix inequality (LMI) constraints. The designed reliable controller can guarantee that the output of the closed-loop sampled-data system tracks the reference signal without steady-state error. An airship model is considered in this paper and its simulation results are given.

The problem of station-keeping attitude tracking control for an autonomous airship with system uncertainties and external disturbances is investigated. Adaptive laws are applied to estimate the upper bounds of uncertainties and disturbances, and a nonlinear finite time control scheme is proposed by combing input/output feedback linearization with integral sliding mode technique. Different from the existing works on attitude control of airship, the developed controller can guarantee the yaw, pitch and roll angle trajectories track the desired attitude in finite time in spite of uncertain system uncertainties and external disturbances. Simulation results are provided to illustrate the attitude tracking performance.