Effects of Aerodynamic downforce on Vehicle Control and Stability

This paper deals with the analysis of vehicle handling with the variation of downforce. A vehicle with aero package were taken and the values of aerodynamic downforce and front downforce distribution for different front and rear ride heights were taken. This was followed by the generation of yaw moment diagram at original ground clearance of 30mm. Aero map data were collected and individual yaw moment diagrams were collected from which vehicle handling parameters are noted. Different contour plots were made to understand the variation of vehicle handling with different ride heights (aerodynamics downforce and downforce distribution). The paper concludes with the sensitivity study where effects of aerodynamic downforce were recorded on vehicle control and stability.

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A Feedback Control Strategy for Torque-Vectoring of IWM Vehicles

Volume 3: 16th International Conference on Advanced Vehicle Technologies; 11th International Conference on Design Education; 7th Frontiers in Biomedical Devices ◽

10.1115/detc2014-34372 ◽

2014 ◽

Cited By ~ 3

Author(s):

Francesco Braghin ◽

Edoardo Sabbioni ◽

Gabriele Sironi ◽

Michele Vignati

Keyword(s):

Electric Vehicles ◽

Automotive Industry ◽

Control Strategy ◽

Control Logic ◽

Power Train ◽

Vehicle Handling ◽

Torque Vectoring ◽

Feedback Control Strategy ◽

Object Of Study ◽

Yaw Moment

In last decades hybrid and electric vehicles have been one of the main object of study for automotive industry. Among the different layout of the electric power-train, four in-wheel motors appear to be one of the most attractive. This configuration in fact has several advantages in terms of inner room increase and mass distribution. Furthermore the possibility of independently distribute braking and driving torques on the wheels allows to generate a yaw moment able to improve vehicle handling (torque vectoring). In this paper a torque vectoring control strategy for an electric vehicle with four in-wheel motors is presented. The control strategy is constituted of a steady-state contribution to enhance vehicle handling performances and a transient contribution to increase vehicle lateral stability during limit manoeuvres. Performances of the control logic are evaluated by means of numerical simulations of open and closed loop manoeuvres. Robustness to friction coefficient changes is analysed.

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A direct yaw moment controller for a four in-wheel motor drive electric vehicle using adaptive sliding mode control

Proceedings of the Institution of Mechanical Engineers Part K Journal of Multi-body Dynamics ◽

10.1177/1464419318807700 ◽

2019 ◽

Vol 233 (3) ◽

pp. 549-567 ◽

Cited By ~ 3

Author(s):

Aria Noori Asiabar ◽

Reza Kazemi

Keyword(s):

Sliding Mode Control ◽

Control Algorithm ◽

Sliding Mode ◽

Adaptive Sliding Mode Control ◽

Regenerative Braking ◽

Lane Change ◽

Unknown Parameters ◽

Vehicle Handling ◽

Adaptive Sliding Mode ◽

Yaw Moment

In this paper, a direct yaw moment control algorithm is designed such that the corrective yaw moment is generated through direct control of driving and braking torques of four in-wheel brushless direct current motors located at the empty space of vehicle wheels. The proposed control system consists of a higher-level controller and a lower-level controller. In the upper level of proposed controller, a PID controller is designed to keep longitudinal velocity constant in manoeuvres. In addition, due to probable modelling error and parametric uncertainties as well as adaptation of unknown parameters in control law, an adaptive sliding mode control through adaptation of unknown parameters is presented to yield the corrective yaw moment such that the yaw rate tracks the desired value and the vehicle sideslip angle maintains limited so as to improve vehicle handling stability. The lower-level controller allocates the achieved control efforts (i.e. total longitudinal force and corrective yaw moment) to driving or regenerative braking torques of four in-wheel motors so as to generate the desired tyre longitudinal forces. The additional yaw moment applied by upper-lever controller may saturate the tyre forces. To this end, a novel longitudinal slip ratio controller which is designed based on fuzzy logic is included in the lower-level controller. A tyre dynamic weight transfer-based torque distribution algorithm is employed to distribute the motor driving torque or regenerative braking torque of each in-wheel motor for vehicle stability enhancement. A seven degree-of-freedom non-linear vehicle model with Magic Formula tyre model as well as the proposed control algorithm are simulated in Matlab/Simulink software. Three steering inputs including lane change, double lane change and step-steer manoeuvres in different roads are investigated in simulation environment. The simulation results show that the proposed control algorithm is capable of improving vehicle handling stability and maintaining vehicle yaw stability.

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On-board-tire-model reference control for cooperation of 4WS and direct yaw moment control for improving limit performance of vehicle handling Yoshimi Furukawa (Honda R & D), Masato Abe (Kanagawa Institute of Technology)

JSAE Review ◽

10.1016/s0389-4304(97)84981-8 ◽

1997 ◽

Vol 18 (2) ◽

pp. 189

Keyword(s):

Tire Model ◽

Model Reference ◽

Vehicle Handling ◽

Direct Yaw Moment Control ◽

Model Reference Control ◽

Yaw Moment Control ◽

Moment Control ◽

Institute Of Technology ◽

Yaw Moment

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Comparison of 4WS and direct yaw moment control (DYC) for improvement of vehicle handling performance Masato Abe, Naoto Ohkubo, Yoshio Kano (Kanagawa Institute of Technology/Japan), pp. 159–164, 8 figs., 3 refs.

JSAE Review ◽

10.1016/0389-4304(95)94912-7 ◽

1995 ◽

Vol 16 (2) ◽

pp. 214

Keyword(s):

Vehicle Handling ◽

Handling Performance ◽

Direct Yaw Moment Control ◽

Yaw Moment Control ◽

Moment Control ◽

Institute Of Technology ◽

Yaw Moment

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Gain-scheduled LPV/H∞ controller based on direct yaw moment and active steering for vehicle handling improvements

49th IEEE Conference on Decision and Control (CDC) ◽

10.1109/cdc.2010.6171089 ◽

2010 ◽

Cited By ~ 6

Author(s):

M. Doumiati ◽

O. Sename ◽

J. Martinez ◽

L. Dugard ◽

C. Poussot-Vassal

Keyword(s):

Vehicle Handling ◽

Active Steering ◽

Gain Scheduled ◽

Yaw Moment

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Direct Yaw Moment Control for Enhancing Handling Quality of Lightweight Electric Vehicles with Large Load-To-Curb Weight Ratio

Applied Sciences ◽

10.3390/app9061151 ◽

2019 ◽

Vol 9 (6) ◽

pp. 1151 ◽

Cited By ~ 3

Author(s):

Pongsathorn Raksincharoensak ◽

Sato Daisuke ◽

Mathias Lidberg

Keyword(s):

Experimental Study ◽

Vehicle Dynamics ◽

Driving Simulator ◽

Feedback Gain ◽

Lane Change ◽

Vehicle Handling ◽

Feed Forward ◽

Yaw Rate ◽

Rate Feedback ◽

Yaw Moment

In this paper a vehicle dynamics control system is designed to compensate the change in vehicle handling dynamics of lightweight vehicles due to variation in loading conditions and the effectiveness of the proposed design is verified by simulations and an experimental study using a fixed-base driving simulator. Considering the electrification of future mobility, the target vehicle of this research is a lightweight vehicle equipped with in-wheel motors that can generate an additional direct yaw moment by transverse distribution of traction forces to control vehicle yawing as well as side slip motions. Previously, the change in vehicle handling dynamics for various loading conditions have been analyzed by using a linear two-wheel vehicle model in planar motion and a control law of the DYC system based on feed-forward of front steering angular velocity and feedback of vehicle yaw rate. The feed-forward controller is derived based on the model following control with approximation of the vehicle dynamics to 1st-order transfer function. To make the determination of the yaw rate feedback gain model-based and adaptable to various vehicle velocity conditions, this paper selects a method where the yaw rate feedback gain in the DYC system is determined in a way that the steady-state yaw rate gain of the controlled loaded vehicle matches the gain of the unloaded vehicle. The DYC system is simulated in a single lane change maneuver to confirm the improved responsiveness of the vehicle while simulations of a double-lane change maneuver with a driver steering model confirms the effectiveness of the DYC system to support tracking control. Finally, the effectiveness of the proposed DYC system is also verified in an experimental study with ten human drivers using a fix-based driving simulator.

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Utilising the Potential of Individual Wheel Control on a 6x6 Off-Road Vehicle

10.1115/imece2001/de-23279 ◽

2001 ◽

Author(s):

Andrew Jackson ◽

Michael Brown ◽

David Crolla ◽

Adrian Woodhouse ◽

Michael Parsons

Keyword(s):

Hybrid Electric Vehicle ◽

Mobility Control ◽

Wheel Slip ◽

Vehicle Handling ◽

Conventional Vehicle ◽

Handling Characteristics ◽

Wheel Torque ◽

Yaw Moment Control ◽

Hybrid Configuration ◽

Yaw Moment

Abstract This paper will present a form of mobility control for a 6x6 Hybrid Electric Vehicle (HEV). The vehicle concerned is a series configured HEV utilising Hub Mounted Electric Drives (HMED) at each of the six wheel stations to provide Individual Wheel Control (IWC). Whereas a conventional vehicle needs individual brake actuators or bulky differentials to vary individual wheel torques, IWC can be realised in this hybrid configuration through software control of each HMED, making it potentially more accurate, responsive and flexible than a mechanically implemented version. Direct Yaw-moment Control (DYC) is a method of regulating individual wheel torque to control vehicle yaw motion, providing greater stability in cornering. By varying the torque applied to the left and right wheels, tyre forces can be controlled to produce a desired yaw moment. Not only can this be used to aid cornering, but also to reject disturbances, such as side winds, in straight line running. When combined with a Traction Control System (TCS), optimisation of these tyre forces are considered, ensuring that the vehicle handling characteristics remain stable while acceleration performance is improved. When integrating these two systems, consideration is given to the torque demands of each controller. This co-ordinated control ensures that the vehicle takes full advantage of the torque capabilities associated with the electric motor to provide improved vehicle handling, acceleration and stability. The proposed control algorithms are implemented in MATLAB/SIMULINK on a basic non-linear vehicle handling model utilising a Dugoff tyre model to determine longitudinal and lateral tyre forces. The torque of each individual wheel is controlled to maintain a desired yaw rate and/or wheel slip. The model is then simulated on a number of road surfaces, undertaking a variety of test manoeuvres to assess the potential improvements that the combined controller can offer over a vehicle with fixed-torque distribution. The paper shows how the resultant controller offers a robust method of improving vehicle mobility, providing good stability under varying conditions.

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Vehicle direct yaw moment control system based on the improved linear quadratic regulator

Industrial Robot the international journal of robotics research and application ◽

10.1108/ir-08-2020-0168 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Xianyi Xie ◽

Lisheng Jin ◽

Guo Baicang ◽

Jian Shi

Keyword(s):

Linear Quadratic Regulator ◽

Objective Evaluation ◽

Linear Quadratic ◽

Vehicle Handling ◽

Content Type ◽

The Road ◽

Direct Yaw Moment Control ◽

Yaw Moment Control ◽

Moment Control ◽

Yaw Moment

Purpose This study aims to propose an improved linear quadratic regulator (LQR) based on the adjusting weight coefficient, which is used to improve the performance of the vehicle direct yaw moment control (DYC) system. Design/methodology/approach After analyzing the responses of the side-slip angle and the yaw rate of the vehicle when driving under different road adhesion coefficients, the genetic algorithm and fuzzy logic theory were applied to design the parameter regulator for an improved LQR. This parameter regulator works according to the changes in the road adhesion coefficient between the tires and the road. Hardware-in-the-loop (HiL) tests with double-lane changes under low and high road surface adhesion coefficients were carried out. Findings The HiL test results demonstrate the proposed controllers’ effectiveness and reasonableness and satisfy the real-time requirement. The effectiveness of the proposed controller was also proven using the vehicle-handling stability objective evaluation method. Originality/value The objective evaluation results reveal better performance using the improved LQR DYC controller than a front wheel steering vehicle, especially in reducing driver fatigue, improving vehicle-handling stability and enhancing driving safety.

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