The kinematical model of a truck-trailer mobile robot is analyzed and used for designing a positioning control system based on linear controllers integrated in a fuzzy-logic approach, taking into account both positioning performance and jack-knife avoidance. The results of robot positioning control are extended to trajectory following for which a novel strategy is proposed applicable to general-shape desired trajectories. The effectiveness of the proposed control strategies are verified for linear, circular and sinusoidal trajectories where the mobile robot attains and follows the desired trajectory, avoiding jack-knife positions and with bounded values of input steering angle.