Control Of Lateral Vehicle Dynamics Research Articles

Data-driven design of model-free control for reference model tracking based on an ultra-local model: Application to vehicle yaw rate control

Lateral vehicle dynamics control is important for autonomous driving. This paper presents a data-driven design of model-referenced model-free control (DD-MR-MFC) based on an ultra-local model for vehicle yaw rate control. The characteristics of lateral vehicle dynamics systems depend on vehicle velocities and weights. For this system, fixed proportional–integral–derivative (PID) controllers cannot provide the desired control performance. Additionally, although model-based control can be applied to lateral vehicle dynamics, the modeling process is time-consuming. To efficiently design controllers that can realize the desired performance, we adopt a model-free approach. In this study, the control law of practical MR-MFC is derived by extending the traditional MFC based on an ultra-local model and using a data-driven design method. The MFC approach can be applied to nonlinear systems with few parameters, and the data-driven method provides optimized parameters from single-experiment time-series data without the need for repeated experiments and system model to be controlled. Additionally, the processing cost is considerably low because the controller parameter can be obtained using least-square methods. The effectiveness of the proposed method is verified using a multibody vehicle simulator. The yaw rate tracking performance is examined under different velocities and loads. Results showed that the root-mean-square error of the proposed method is approximately 1/100th of that when using a fixed PID controller optimized using a data-driven method.

Set-Based Actuator Reconfguration Analysis for the Integrated Control of Lateral Vehicle Dynamics

The paper proposes a set-based analysis of steering and braking actuator integration in order to improve the reconfguration strategy of lateral vehicle control. The purpose is to examine the improvement possibilities of the stabilization abilities through actuator integration. The results are applied to the theoretical basis of the actuator selection strategy in the reconfgurable control. In the analysis the computation method of the maximum Controlled Invariant Sets based on the nonlinear Sum-of-Squares (SOS) programming is used. The analysis considers the nonlinear characteristics of the tyre, the velocity and the tyre-road conditions which signifcantly determine the stability regions in the lateral dynamics. Thus, the resulting sets provide information about the stabilization abilities of the actuators for the entire vehicle system. The examination of the integrated actuation in the reconfguration strategy is illustrated through various vehicle manoeuvres.

A new flatness-based control of lateral vehicle dynamics

This paper presents a new concept for vehicle dynamics control (VDC). The control of the longitudinal vehicle dynamics is not discussed, since we are assuming that it is much slower and weakly coupled to the lateral and yawing dynamics. The actuators are considered to be the traction and the braking torques of the individual wheels and only the standard sensors of the common VDC system are used. A modular interface to the subordinate wheel control system is provided by choosing the yaw torque as a fictitious control input. The VDC system is designed by means of a two degrees-of-freedom control scheme. It comprises a flatness-based feedforward part and a stabilising feedback part. The reference trajectory generation is introduced for the flat output which is given by the lateral velocity of the vehicle. Thus an advantageous kind of body side-slip angle control is provided with the standard VDC system hardware. Extensive simulation studies show excellent performance of the designed control concept.

Model-Based Supervision and Control of Lateral Vehicle Dynamics

The further improvement of drive dynamic control needs model-based concepts. Two model-based applications are described. Firstly, the one-track model is used to indicate critical driving situations like oversteering or unstable behavior. Experiments with a middle-class vehicle show the results of this supervision and fault detection method.Secondly, it is shown by simulation how the understeering and oversteering behavior can be influenced by anti-roll bar actuation. Then a nonlinear yaw-rate controller for active steering is designed and it is shown by simulation how the steering behavior can be improved by anti-roll actuation.