Gain-scheduled integrated active steering and differential control for vehicle handling improvement
57
Citation
22
Reference
10
Related Paper
Citation Trend
Abstract:
This paper presents a gain-scheduled active steering control and active differential design method to preserve vehicle stability in extreme handling situations. A new formulation of the bicycle model in which tyre slip angles, longitudinal slips and vehicle forward speed appear as varying vehicle parameters is introduced. Such a model happens to be useful in the design of vehicle dynamics controllers scheduled by vehicle parameters: after having expressed the parametric bicycle model in the parametric descriptor form, gain-scheduled active steering and differential controllers are designed to improve vehicle handling at 'large' driver-commanded steering angles. Simulations reveal the efficiency of the selected modelling and controller design methodology in enhancing vehicle handling capacity during cornering on roads with varying adhesion coefficient and under variable speed operation.Keywords:
Automobile handling
Electronic differential
Active Steering
Active safety
This paper presents a gain-scheduled active steering control and active differential design method to preserve vehicle stability in extreme handling situations. A new formulation of the bicycle model in which tyre slip angles, longitudinal slips and vehicle forward speed appear as varying vehicle parameters is introduced. Such a model happens to be useful in the design of vehicle dynamics controllers scheduled by vehicle parameters: after having expressed the parametric bicycle model in the parametric descriptor form, gain-scheduled active steering and differential controllers are designed to improve vehicle handling at 'large' driver-commanded steering angles. Simulations reveal the efficiency of the selected modelling and controller design methodology in enhancing vehicle handling capacity during cornering on roads with varying adhesion coefficient and under variable speed operation.
Automobile handling
Electronic differential
Active Steering
Active safety
Cite
Citations (57)
Active steering is a newly developed technology for passenger cars to enhance vehicle stability and handling performance. A fractional-order PI D λμ control strategy is applied on active steering vehicle based on a multi-body vehicle dynamic model in this paper and the active control is expressed as a sum of PI λ and PD μ control. The multi-body vehicle dynamic model using ADAMS can accurately predict the dynamic performance of the vehicle. A new hybrid steering scheme including both active front steering (applying an additional front steering angle besides the driver input) and rear steering is presented to control both yaw velocity and sideslip angle. The parameters of the controller were optimized by a genetic algorithm (GA) and it can adjust both sideslip angle and yaw velocity through the co-simulation between the ADAMS multi-body vehicle dynamic model and Matlab. The co- simulation scenario takes place at high speed with a single-sine steering angle input to validate the effectiveness of active steering system. Simulation result shows that active steering vehicle with fractional-order PI D λμ control logic strategy can enhance vehicle stability and handling greatly comparing with classical PID controller and traditional front wheel steering vehicle.
Active Steering
Yaw
Automobile handling
Steering linkage
Active safety
Electronic differential
Cite
Citations (0)
Abstract The unstabilization of limit-oversteer vehicles depends heavily on the saturation characteristics of the rear cornering forces. In this paper, an anti-spin condition of vehicles under the saturation characteristics of the rear cornering forces is examined from the view point of robust stability control. Then, an active front wheel steering control system satisfying the anti-spin condition is designed by H∞ control. Furthermore, vehicle maneuverability is improved by adaptive control approach.
Automobile handling
Electronic stability control
Cite
Citations (9)
Several control strategies can be implemented in road vehicles to avoid roll over, improve ride quality or customize handling performance. Handling performance is one of the crucial areas of research from the safety point of view. Most of the control strategies depend on manipulating the motion of the tires, which are the prime source of the forces acting on the vehicle. Some of the common control strategies for handling explored in recent years include: active control of tractive and/or braking torque; and a wide variations in active steering control. For vehicle stability and handling improvement, Active Front and Rear Steering (AFS, ARS) prove to be excellent control techniques, as active torque control fails to generate required forces and moments in certain situations. In recent years, major research effort has been directed towards active steering control, where the steer angle of the wheels is actively controlled to improve handling performance at high speeds. Such controls, however, have limitations as they do not attempt to utilize tires' force generating potential. The present study proposes a new Active Independent Front Steering (AIFS) technique with independent control for each front wheel. A non-linear 4-wheel vehicle model incorporating tire 'Magic formula' and load shifts in longitudinal and lateral direction is studied. This model agrees well with a simpler bicycle model and CarSim simulation. The 4-wheel vehicle model with proposed AIFS is simulated for step and sinusoidal lane-change inputs. A simple PI control algorithm that differentiates between under and oversteer handling characteristics is developed and utilized for the simulations. The results show that by controlling one wheel only, AIFS can provide the ideal yaw-rate and trajectory responses at any speed, and the performances are as good as those obtained by AFS and significantly better than conventional uncontrolled system. Furthermore, AIFS is shown to equalize the tire workload at the left and right front tires improving the vehicle's ability to generate maximum possible lateral force. Only exception to this is when the vehicle is strongly oversteer. It is also shown that this limitation can be overcome by introducing an AIFS where both wheels are actively controlled. A physical design using tandem planetary gear trains is proposed for the AIFS that can provide the required control and is fail safe. The present is a first investigation of AIFS control that has significant potential for the integrated control of road vehicles and is identified in proposed future studies.
CarSim
Active Steering
Automobile handling
Yaw
Active safety
Electronic stability control
Electronic differential
Traction control system
Ride quality
Cite
Citations (2)
It is pointed out that taking the non-linear characteristics of tire and vehicle dynamics into consideration,introducing the chassis control DYC(A direct yaw moment control)is inevitable for improving handling performance and active safety in the vehicle motion with larger side-slip angle and higher lateral acceleration.Emphasis is placed on the need to propose a control strategy based on through observation and understanding of the tire and vehicle dynamics.
Chassis
Active safety
Automobile handling
Yaw
Vehicle safety
Slip angle
Cite
Citations (0)
For improving the vehicle handling at high speed, an optimal controller was introduced for the four-wheel-active-steering vehicle. A closed-loop system was set up by combining vehicle model with driver model. The simulation test in the closed-loop system was carried out to verify control effect of such a optimum controller. Simulation results show that the four-wheel-active-steering vehicle under the optimal control can gain expected control effect such as wiping out sideslip angle and tracking desired yaw rate and so on. In addition, the four-wheel-active-steering vehicle with the optimal control can also track desired trajectory and its following accuracy is better than the traditional front-wheel steering vehicle. So, the steering response characteristic for the four-wheel-active-steering vehicle at high speed is improved.
Active Steering
Yaw
Active safety
Automobile handling
Active suspension
Electronic differential
Cite
Citations (1)
An optimal control approach is developed for Four-Wheel Active Steering Vehicles. First, parameterized vehicle model is built. Second, active steering model is implemented and coupled to the vehicle model. Finally, an optimal control loop, delivering as final output optimal vehicle performances of Four-Wheel Active Steering Vehicles is developed.
Active Steering
Active safety
Electronic differential
Steering linkage
Car model
Cite
Citations (9)
An important development of the steering systems in general is active steering systems like active front steering and steer-by-wire systems. In this paper the current functional possibilities in application of active steering systems are explored. A new approach and additional functionalities are presented that can be implemented to the active steering systems without additional hardware such as new sensors and electronic control units. Commercial active steering systems are controlling the steering angle depending on the driving situation only. This paper introduce methods for enhancing active steering system functionalities depending not only on the driving situation but also vehicle parameters like vehicle mass, tyre and road condition. In this regard, adaptation of the steering ratio as a function of above mentioned vehicle parameters is presented with examples. With some selected vehicle parameter changes, the reduction of the undesired influences on vehicle dynamics of these parameter changes has been demonstrated theoretically with simulations and with real-time driving measurements.
Active Steering
Active safety
Steering system
Steering linkage
Automobile handling
Electronic differential
Cite
Citations (7)
SUMMARYThis paper describes an investigation of active roll control of heavy road vehicles. Results from handling tests performed on an articulated vehicle are used to validate a nonlinear simulation of the vehicle. A simple linear model of the vehicle is used to investigate three strategies for active roll control. The strategies are then implemented on the validated nonlinear model.
Active safety
Automobile handling
Car model
Nonlinear model
Cite
Citations (20)
This article presents the capability of several active systems and smart actuators to control the vehicle yaw motion for various driving situations. A control concept allowing for a centralised coordination of multiple actuators is described. The additional yaw torque generated through system control interventions is determined taking account of the vehicle side slip angle and the lateral acceleration. Analysis results are illustrated for the active front steering and brake system, active differential and active anti-roll bars. The developed control concept is based on a centralised yaw torque allocation algorithm. The concept comprises the coordination of the considered active systems and the identification of required interventions to control the vehicle yaw motion. A sine with dwell time open-loop manoeuvre is utilised to illustrate the stability and agility improvement achieved by the centralised and coordinated control strategy.
Yaw
Active Steering
Automobile handling
Cite
Citations (10)