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Presents a method to design fuzzy logic controllers of autonomous articulated vehicles. The method considers manoeuvres in industrial environments, including backing-up manoeuvres where the angle between the longitudinal axis of a tractor and its trailer takes large values. These manoeuvres are particularly dangerous because the vehicle can reach the so-called "jackknife" position, which is a very dangerous situation because it may cause the destruction of the roller. Stability analysis is a crucial issue in the backing-up manoeuvres of articulated vehicles. However, the existing results on the stability of fuzzy control systems of articulated vehicles are based on the assumption of a small value of the above-mentioned angle, which is not usually the case when manoeuvring in factories. The paper shows how a fuzzy control system which, under this assumption, satisfies the Lyapunov stability criterion, can lead the system to the "jackknife" position. The method proposed in the paper is based on the qualitative theory of nonlinear dynamical systems and does not assume a small angle between the tractor and the trailer. The paper shows how the method guarantees absolute stability of the fuzzy control system and can preclude the "jackknife" position.