Vehicle dynamics

About: Vehicle dynamics is a research topic. Over the lifetime, 12909 publications have been published within this topic receiving 204091 citations.

Robust two degree-of-freedom vehicle steering controller design

Abstract: Robust steering control based on a specific two degree-of-freedom control structure is used here for improving the yaw dynamics of a passenger car. The usage of an auxiliary-steering actuation system for imparting the corrective action of the steering controller is assumed. The design study is based on six operating conditions for vehicle speed and the coefficient of friction between the tires and the road representing the boundary of the operating domain of the vehicle. The design is carried out by finding the region in controller parameter plane where Hurwitz stability and a mixed-sensitivity frequency-domain constraint are simultaneously satisfied. A velocity-based gain scheduling type implementation is used. Moreover, the steering controller has a fading effect that leaves the low-frequency driving task to the driver, intervening only when necessary. The effectiveness of the final design is demonstrated with linear simulations and nonlinear simulations using a highly realistic model of an actual car.

Self sustaining bicycle robot with steering controller

Abstract: Bicycle is a transportation device without any environmental burden. However, bicycle is unstable in itself and it is fall down without human assistance like steering handle or moving upper body. In these days, electric power assistance bicycles are used practically, but all of those bicycles merely assist human with pedal driving and there are no bicycles that help to stabilize its position. Hence, stabilizing the posture and realizing stable driving of a bicycle have been researched. Dynamic model of running bicycle is complicated and it's hard to recognize completely. However, assuming that the rider doesn't move upper body, dynamics of bicycle is represented in equilibrium of gravity and centrifugal force. Centrifugal force is risen out from the running velocity and turning radius determined by steering angle. Under these conditions, it is possible to stabilize bicycle posture by controlling its steering. In this paper, the dynamic model derived from equilibrium of gravity and centrifugal force is proposed. Then the control method for bicycle steering based on acceleration control is proposed. Finally, the validity of this method is proved by the simulations and experimental results.

Vehicle dynamics and external disturbance estimation for vehicle path prediction

Abstract: This paper addresses the onboard prediction of a motor vehicle's path to help enable a variety of emerging functions in autonomous vehicle control and active safety systems. It is shown in simulation that good accuracy of path prediction is achieved using numerical integration of a linearized two degree of freedom vehicle handling model. To improve performance, a steady-state Kalman filter is developed to estimate the vehicle's lateral velocity and the magnitudes of external disturbances acting on the vehicle, specifically the lateral force and the yaw moment disturbances. A comparison is made between three models of external disturbance time variation; a piecewise-constant-in-time model is found to be sufficient. Finally, an algorithm is proposed to characterize path prediction uncertainty using a statistical characterization of the measurement and modeling errors. Simulation suggests that these algorithms may provide a useful suite of path prediction tools for a variety of applications.