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A control strategy is proposed to improve the high-speed lateral performance of an A-double (tractor-semitrailer-dolly-semitrailer) combination vehicle using active steering of the front axle of the dolly. The strategy is realized as a H∞-type static output feedback combined with dynamic feed-forward. The static output feedback synthesis is based on a previous work from the literature, while novel linear matrix inequality (LMI) conditions have been derived for dynamic feed-forward synthesis that can also be used for uncertain systems. The proposed controller has a simple structure and is easy to implement from a practical point of view since it requires only the driver steering angle (for feed-forward) and just one articulation angle measurement (for feedback). Obtained using a high-fidelity vehicle model, the synthesis results confirm a significant reduction in the rearward amplifications of the yaw rate and the lateral acceleration as well as the high-speed transient off-tracking during sudden lane change maneuvers.

A control strategy based on H∞-type static output feedback combined with dynamic feed-forward is proposed to improve the high-speed lateral performance of an A-double combination vehicle(tractor–se...

This paper proposes a robust load-dependent controller synthesis to improve the lateral stability and performance of an A-double vehicle (tractor-semitrailer-dolly-semitrailer) at high speeds and consequently road safety by active steering of the dolly unit. The mass of the semitrailers resides in an interval between empty and fully-loaded scenarios and can be measured online. The yaw moments of inertia of the semitrailers can significantly change depending on loading conditions. In order to design a gain-scheduled controller with the mass of the semitrailers as scheduling parameters and to guarantee the system performance against the yaw moment of inertia variations in the semitrailers, a linear matrix inequality (LMI)-based design framework has been utilized. In this formulation, a descriptor-form representation of the vehicle model is used in order to avoid dealing with rational parameter dependency. The controller synthesis is formulated as an $\mathcal{H}_{\infty}$ -type static output feedback (SOFB), which uses information from one articulation angle which is easily measurable in practice. The simulations results indicate significant improvements in the high-speed lateral performance of the A-double in various loading conditions by suppressing undesired oscillations in the yaw rate of the last semitrailer during sudden lane change manoeuvres.

This paper proposes a gain-scheduled controller synthesis for improving the lateral performance and stability of articulated heavy vehicles by active steering of the selected towed vehicle units. The longitudinal velocity is on-line measurable, and it is thus treated as a scheduling parameter in the gain-scheduled controller synthesis. The lateral performance of four articulated heavy vehicles, including existing Nordic heavy vehicles and prospective longer articulated heavy vehicles, are investigated with and without active steering and compared with a commonly used conventional tractor–semitrailer. The control problem is formulated as an [Formula: see text] static output feedback, which uses only information from articulation angles between the steered vehicle unit and the vehicle unit in front of it. The solution of the problem is obtained within the linear matrix inequality framework, while guaranteeing [Formula: see text] performance objectives. Effectiveness of the designed controller is verified through numerical simulations performed on high-fidelity vehicle models. The results confirm a significant reduction in yaw rate rearward amplification, lateral acceleration rearward amplification, and high-speed transient off-tracking, thereby improving the lateral stability and performance of all studied heavy vehicles at high speeds.

A robust steering-based controller synthesis is presented for an A-double combination vehicle with a steerable dolly. The controller ensures robust stability and performance in the face of uncertainties in the cornering stiffness of the tyres and the moments of inertia of the semitrailers, which are treated as time-varying and time-invariant parameters respectively. A descriptor-type representation of the system is employed since a standard state-space model depends rationally on the moments of inertia. The controller synthesis is formulated as an Hinfinity-type static output feedback, which uses information from only one articulation angle. The driver steering input is also used by including a static feed-forward. The proposed synthesis method is based on linear matrix inequality (LMI) optimisation. The controller is verified based on the simulation results obtained from both (approximate) linear and (high-fidelity) nonlinear vehicle models. The results indicate significant improvement in the high-speed lateral performance of the A-double in the presence of parametric uncertainties.

A robust static output feedback controller is developed for improving the high speed lateral performance of an A-double combination by active steering of the dolly unit. The controller is designed to be robust against the uncertainty in the cornering stiffness parameters of the tires in the semitrailers. Both H∞ and generalized H2 synthesis approaches are discussed together with their solutions in the form of linear matrix inequality (LMI) optimizations. The control syntheses are then applied to both a fixed system and an uncertain parameter-dependent system. The verification results confirm a significant reduction in rearward amplification of yaw rates and high speed transient off-tracking. To validate the simulation results, an advanced high-fidelity vehicle model is used.

This paper proposes a new linear matrix inequality (LMI) approach for static output feedback synthesis under an integral quadratic constraint (IQC) on the states. The proposed approach is applicable to a wider class of systems if compared to the relevant previous work. The new sufficient LMI condition for the IQC constraint might also be preferable to work with when considering systems that have affine parameter dependence in the descriptor form. As a particularly relevant application, the proposed approach is then considered for the control of a high capacity transport vehicle to enhance its lateral performance. The verification results confirm significant reductions in rearward amplification of yaw rates and high speed transient offtracking for the nominal system.

This paper shows how actuator coordination, based on control allocation, can be used in the motion control system for long articulated heavy vehicles. Usage of a control allocation structure is one way to handle an over-actuated system, which is a system where there are more motion actuators than controlled motions. The A-double combination is in focus for the control allocation design, which is based on vehicle modelling using the Lagrange formulation. The control structure is tested in a simulation environment and evaluated by two test scenarios. For the selected configuration with 31 actuators, the control allocation method coordinates the desired motion for both large and small steer and articulation angles. The proposed control structure is shown to be convenient when the vehicle configuration, for example the number of actuators in the combination, is changed.