Active Roll Control Research Articles

Adaptive robust control methodology for active roll control system with uncertainty

The active roll control system (ARCS) can impose anti-roll moment quickly to prevent the vehicle rolling when the vehicle generates the roll tendency and effectively enhance the vehicle dynamic performance without sacrificing the ride comfort. In the dynamic model of the ARCS, the sprung mass of the vehicle is considered to be the uncertain parameter, which is (possibly) fast-varying. However, what we know about the uncertainty is just that it is bounded. Furthermore, the bound is unknown. The target roll angle is regarded as the constraint when the vehicle equipped with the ARCS is running under a given case. Taking the parameter uncertainty and possible initial condition deviation from the constraint into account, an adaptive robust control scheme based on the Udwadia and Kalaba’s approach is proposed to drive the ARCS to follow the pre-specified constraint approximately. The adaptive law is of leakage type which can adjust itself based on the tracking error. Numerical simulation shows that by using the adaptive robust control scheme, the error between the actual roll angle and the desired roll angle converges to zero quickly in 0.3 s from initial error 0.287 deg, and the final error is of the order of $$10^{-7}$$ . Thus, the control design renders the ARCS practically stable and achieves constraints following maneuvering.

V2V 통신과 CDC를 이용한 능동 롤 예견 제어

V2V 통신과 CDC를 이용한 능동 롤 예견 제어

Optimal design for robust control parameter for active roll control system: a fuzzy approach

In this paper, we investigate the dynamical model of an active roll control system (ARCS) which can impose an anti-roll moment quickly by active actuators to prevent a vehicle rolling when the vehicle generates the roll tendency and effectively enhances the vehicle dynamic performance without sacrificing ride comfort. In the dynamic model of the ARCS, we consider the sprung mass of the vehicle which is (possibly) time-varying and the initial conditions are the uncertain parameters which are described by fuzzy set theory. A new optimal robust control which is deterministic and is not the usual if–then rules-based control is proposed. The desired controlled system performance is twofold: one deterministic, which includes uniform boundedness and uniform ultimate boundedness, and one fuzzy, which enhances the cost consideration. We then formulate an optimal design problem associated with the control as a constrained optimization problem. The resulting control design is systematic and is able to guarantee the deterministic performance and minimize the average fuzzy performance. Numerical simulations show that the control design renders the ARCS practically stable and achieves constraints following maneuvering.

Design of an integrated control system to enhance vehicle roll and lateral dynamics

Besides lateral instability, one major threat to all ground vehicles, especially SUVs, is the danger of rollover during cornering. A coordination strategy based on fuzzy logic has been devised to coordinate the sub-controls; namely, active steering, active differential, active brake and a novel active roll control system. Independent study of each sub-control as well as an analysis of their inter-relationship has been carried out. The coordination strategy is supposed to resolve the conflict among control targets – which are sideslip regulation, yaw rate tracking, lateral acceleration tracking and roll motion control – all of which are to be done while maintaining the driver’s desired longitudinal acceleration. Thus, a compromise must be reached. Vehicle sideslip angle and yaw rate were considered to be the criteria for lateral stability; and a combination of roll angle, roll rate and lateral load transfer was selected as the criterion for roll stability. The results of simulations on two SUV models in CarSim software indicate that the integrated controller can successfully restore vehicles’ stability in critical condition.

A design synthesis framework for directional performance optimization of multi-trailer articulated heavy vehicles with trailer lateral dynamic control systems

This paper presents a design synthesis framework for directional performance optimization of multi-trailer articulated heavy vehicles with trailer lateral dynamic control systems, e.g. active trailer steering, trailer differential braking, active roll control or the coordination of the three systems. In order to demonstrate the effectiveness of the proposed framework, it was applied to the design optimization of a multi-trailer articulated heavy vehicle with an active trailer steering controller. In the design, a set of lateral stability measures is originally defined, and the design problem under simulated test manoeuvres is implemented using a parallel computing technique. It is illustrated that the proposed framework and the performance measures can be used to identify effectively the desired variables and to predict reliably the performance envelopes of multi-trailer articulated heavy vehicles with active safety systems by considering the concept of driver-adaptive-vehicle design.

A new robust controller to improve the lateral dynamic of an articulated vehicle carrying liquid

In this paper to improve manoeuvrability and jackknifing prevention, as well as increasing rollover stability of an articulated vehicle carrying liquid, a new control system coupled with an active roll control system and an active steering control system is presented. First, a 16-degrees-of-freedom nonlinear dynamic model of an articulated vehicle is developed. Next, the dynamic interaction of the liquid cargo with the vehicle is investigated by integrating a quasi-static liquid sloshing model with a tractor semi-trailer model. Initially, to improve the roll stability of the vehicle, an active roll control system is presented. The active anti-roll bar is employed as an actuator to generate the roll moment. Furthermore, the manoeuvrability increment and jackknifing prevention are targeted using the active steering control system. The main purpose of using the active steering controller is to track the desired values of tractor yaw rate, articulation angle and tractor lateral velocity in different roads, various filled volumes and different speeds. The active steering control system is designed based on a three-degrees-of-freedom dynamic model of the articulated vehicle carrying liquid and on the basis of sliding mode control. Simulation results confirmed robust performance of the control system for different filled volumes, especially during the critical manoeuvre. Further studies show that the tracking of the desired articulation angle has not only eliminated the off-tracking path, but also has made the semi-trailer rear end follow the fifth wheel path.

Improvement in the rollover stability of a liquid-carrying articulated vehicle via a new robust controller

In this paper, in order to improve the roll stability of an articulated vehicle carrying a liquid, an active roll control system is utilized by employing two different control methods. First, a 16-degree-of-freedom non-linear dynamic model of an articulated vehicle is developed. Next, the dynamic interaction of the liquid cargo with the vehicle is investigated by integrating a quasi-dynamic liquid sloshing model with a tractor–semitrailer model. Initially, to improve the lateral dynamic stability of the vehicle, an active roll control system is developed using classical integral sliding-mode control. The active anti-roll bar is employed as an actuator to generate the roll moment. Next, in order to verify the classical sliding-mode control performance and to eliminate its chattering, the backstepping method and the sliding-mode control method are combined. Subsequently, backstepping sliding-mode control as a new robust control is implemented. Moreover, in order to prevent both yaw instability and jackknifing, an active steering control system is designed on the basis of a simplified three-degree-of-freedom dynamic model of an articulated vehicle carrying a liquid. In the introduced system, the yaw rate of the tractor, the lateral velocity of the tractor and the articulation angle are considered as the three state variables which are targeted in order to track their desired values. The simulation results show that the combined proposed roll control system is more successful in achieving target control and reducing the lateral load transfer ratio than is classical sliding-mode control. A more detailed investigation confirms that the designed active steering system improves both the lateral stability of the vehicle and its handling, in particular during a severe lane-change manoeuvre in which considerable instability occurs.

An Integrated Control of Differential Braking, Front/Rear Traction, and Active Roll Moment for Limit Handling Performance

This paper describes an integrated chassis control (ICC) algorithm of differential braking, front/rear traction torque, and active roll moment control. The integrated control algorithm is designed to maximize driving velocity and enhance vehicle lateral stability in cornering. The target longitudinal acceleration is determined based on the driver's intention and vehicle current status to ensure vehicle lateral stability in high-speed maneuvering. An optimization-based control allocation strategy is used to distribute the actuator control inputs optimally under consideration of tire and vehicle limitations. Closed-loop simulations of a driver-vehicle-controller system were conducted to investigate the performance of the proposed control algorithm. The performance of the ICC has been compared with those of individual chassis control systems, such as electronic stability control, four-wheel drive (4WD), and active roll control system. The simulation results show that the proposed ICC algorithm improves the performance in high-speed cornering with respect to driving speed without losing stability, compared with individual chassis control systems.

Coordinated control of active steering and active roll control systems for enhanced vehicle lateral dynamics

In this paper, the coordinated control of active steering and active roll control systems is investigated aiming to enhance vehicle lateral dynamics performance. A combined control structure is employed to design active steering controller, in which feedback controller is designed using robust mixed sensitivity control approach to minimise the tracking error of yaw rate and body sideslip angle. To further improve vehicle cornering capacity, an active roll controller based on the yaw rate feedback is designed by re-distributing roll moments between the front and rear axles to collaborate together with active steering. The proposed control system is evaluated via computer simulations under different manoeuvres. The simulation results show the overall performance improvement using the proposed coordinated control system in terms of the better handling performances.

Coordinated control of active steering and active roll control systems for enhanced vehicle lateral dynamics

In this paper, the coordinated control of active steering and active roll control systems is investigated aiming to enhance vehicle lateral dynamics performance. A combined control structure is employed to design active steering controller, in which feedback controller is designed using robust mixed sensitivity control approach to minimise the tracking error of yaw rate and body sideslip angle. To further improve vehicle cornering capacity, an active roll controller based on the yaw rate feedback is designed by re-distributing roll moments between the front and rear axles to collaborate together with active steering. The proposed control system is evaluated via computer simulations under different manoeuvres. The simulation results show the overall performance improvement using the proposed coordinated control system in terms of the better handling performances.

Integrated control of the differential braking, the suspension damping force and the active roll moment for improvement in the agility and the stability

This paper describes an integrated control strategy of the differential braking, the semiactive suspension damper and the active roll moment. Integrated control is designed to improve the agility and the stability of a vehicle by simultaneous control of the yaw rate and the roll motion. The proposed integrated chassis control algorithm consists of a supervisor, vehicle motion control algorithms and a coordinator. The supervisor monitors the vehicle status and determines the desired vehicle motions such as the desired yaw rate and the desired roll motion based on control modes to improve the stability and the agility of the vehicle. The control algorithm calculates the desired yaw moment and the desired roll moment for generation of the desired vehicle motions. The coordinator determines the brake pressures, the damper current and the active roll moment to generate the desired yaw moment and the desired roll moment. The roll moment and the yaw moment can be controlled simultaneously by the use of the active anti-roll bar motor torque. Open-loop and closed-loop simulations of a driver–vehicle–controller system were conducted to investigate the performance of the proposed control algorithm. The performance of the proposed integrated chassis control algorithm was compared with those of the individual chassis control systems, such as the electronic control suspension and the an active roll control system. It was shown from the simulation results that the proposed integrated chassis control system can provide a significantly improved performance with respect to the agility, the manoeuvrability and the roll stability of a vehicle compared with the performances of the individual chassis control systems.

승차감 향상과 차량 전복 방지를 위한 능동 롤 제어기의 성능 비교

This paper presents a comparison among three types of approaches to an ARC (Active Roll Control) with an AARB(Active Anti-Roll Bar) for a vehicle system. Lateral acceleration and road profile are considered as disturbance. The ARC is designed with an LQ SOF (Linear Quadratic Static Output Feedback) control, <TEX>$H_{\infty}$</TEX> control and SMC (Sliding Mode Control). These approaches are compared in terms of rollover prevention and ride comfort. For comparison, Bode plot analysis based on linear model and frequency response analysis based on CarSim simulation are performed.

Active carbody roll control in railway vehicles using hydraulic actuation

Carbody tilting is used in railway vehicles to reduce the exposure of passengers to lateral acceleration in curves, allowing these to be negotiated at higher speeds with the same level of comfort. This, however, requires a rather complex actuation system that increases vehicle weight and reduces space for passengers.This paper introduces a new concept that provides a limited amount of carbody tilt using hydraulic actuation. The device consists of interconnected hydraulic actuators attached to the carbody and bogies, replacing the passive anti-roll bar used in railway vehicles and in addition permitting active tilt control.Three control strategies for the active hydraulic suspension are proposed, and the regulator gains are defined using Genetic Algorithm optimisation, based on numerical simulation of the running behaviour of the actuated railway vehicle in a high-speed curve. Finally, the performance of the actuated vehicle is assessed on the basis of numerical simulations, showing it is possible to increase significantly the vehicle׳s running speed in fast curves compared with a vehicle equipped with passive suspension.

Simulation and experimental evaluations on the performance of pneumatically actuated active roll control suspension system for improving vehicle lateral dynamics performance

This paper presents the derivation of a full vehicle model which consists of ride, handling and tyre subsystems to study vehicle dynamics behaviour in the lateral direction. The full vehicle model is then validated experimentally using an instrumented experimental vehicle based on steering wheel input from the driver. Three types of vehicle dynamics test were performed for model validation, namely step steer, slalom and double lane change tests. The validation results show that the behaviours of the model are similar to the real vehicle with acceptable error. An Active Roll Control (ARC) suspension system was developed using the validated full vehicle model to reduce unwanted vehicle motions during steering input manoeuvres such as body roll angle, body roll rate, vertical acceleration of the body and body heave. The proposed controller for the ARC system is a combination of Proportional-Integral-Derivative (PID) control with roll moment rejection loop. The results of the study show that the proposed control structure significantly improves the dynamics performance of the vehicle during step steer, slalom and double lane change manoeuvres compared with a passive vehicle system. The additional roll moment rejection loop is found to be able to further improve the performance of the PID ARC system. The effectiveness of the ARC system with the proposed control was also proven experimentally using the instrumented experimental vehicle.

Control Systems Integration for Enhanced Vehicle Dynamics

This paper deals with improving comfort and handling for a ground vehicle through the coordinated control of different active systems available in passenger cars, e.g., electronic stability control, active roll control and engine torque control. The authors first describe separate control systems, each with its logic, showing advantages and limits, then propose various possible integrations, aiming at exploiting the benefits of a coordinated approach. Finally, the proposed control logics are tested on a vehicle model: simulation results prove the effectiveness of the approach in improving vehicle response during typical handling maneuvers.

An Investigation into Coordinated Control of 4-wheel Independent Brakes and Active Roll Control System for Vehicle Stability

An Investigation into Coordinated Control of 4-wheel Independent Brakes and Active Roll Control System for Vehicle Stability

Development of Integrated Control of Electronic Stability Control, Continuous Damping Control and Active Anti-Roll Bar for Vehicle Yaw Stability

This paper describes an investigation into coordinated control of electronic stability control (ESC), continuous damping control (CDC) and active roll control system (ARC). The coordinated control is suggested to improve the vehicle stability and agility features by yaw rate control. At first, the relation of roll moment distribution and yaw dynamics is analyzed based on simplified tire model. The proposed integrated chassis control algorithm consists of a supervisor, control algorithms, and a coordinator. The supervisor monitors the vehicle status and determines desired vehicle motions such as a desired yaw rate and desired roll motion based on control modes to improve vehicle stability. According to the corresponding the desired vehicle dynamics, the control algorithm calculated a desired yaw moment and desired roll moment, respectively. Based on the desired yaw moment and the desired roll moment, the coordinator determines the brake pressures, the ARC motor torques and damper current based on control strategies. The ARC motor torque has been calculated to generate the roll moment and yaw moment simultaneously. Closed loop simulations with a driver-vehicle-controller system were conducted to investigate the performance of the proposed control strategy using CarSim vehicle dynamics software and the integrated controller coded using Matlab/Simulink.

SUV 차량용 전동식 능동 롤 제어 시스템의 성능 평가 기술 연구

차량 선회 시 조종안정성과 주행 승차감을 향상시키기 위하여 능동적으로 차체의 롤(roll)을 줄이기 위한 연구가 진행되고 있다. 전동식 능동 롤 제어(ARC) 시스템은 전후 스테빌라이저바 중앙에 위치한 전동 모터 방식의 구동기에 의해 차량의 차체 롤을 제어한다. 본 연구에서는 이러한 전동식 ARC 시스템의 제어 성능 및 차량 동역학적 특성을 평가하고 검증하기 위한 해석, 벤치 시험, 실차 시험의 3단계 절차와 방법을 제안하였다. ARC 제어로직의 성능 및 타당성 평가를 위한 Matlab/Simulink와 CarSim간의 연동-해석 방법을 제안하였고, ARC 구동기 및 시스템의 성능을 평가하기 위한 벤치 시험 방법과 실차 시험 방법을 제안하였다.

Study on the Time Lag between Steering Input and Vehicle Lateral Acceleration Response under Different Key Vehicle Parameters

A passively suspended road vehicle rolls outwards under the influence of lateral acceleration when cornering, which is very dangerous under large lateral acceleration. In this paper, time lag between steering input and vehicle lateral acceleration response is systematically studied to implement the active roll control algorithm from the viewpoint of vehicle system dynamics. A 3 DOF yaw-roll vehicle model is established based on vehicle lateral, roll and yaw dynamics. Vehicle parameters of a 1997 Jeep Cherokee is used for parametric study, where the influences of vehicle velocity, steering frequency, mass, length, roll, yaw moment of inertia, position of vehicle centre of gravity, and tyre cornering stiffness are studied via numerical simulation. The analysis results will help improve the real time rollover warning/control algorithm design for vehicle safety.

Design of an active roll control system for hybrid four-wheel-drive vehicles

This paper presents a method for designing an active roll control system, combined with integrated chassis control for hybrid four-wheel-drive vehicles. The active roll control system adopts an active anti-roll bar as an actuator and is designed by model matching control with a roll estimator. To maintain the manoeuvrability of hybrid four-wheel-drive vehicles with an active roll control system, integrated chassis control is adopted. The hybrid four-wheel-drive vehicle consists of a front internal-combustion engine and independent motor-driven rear wheels and is equipped with electronic stability control, active front steering and four-wheel drive. Direct yaw moment control is used to generate a control yaw moment. Weighted pseudo-inverse-based control allocation and simulation-based optimization are proposed to distribute the control yaw moment. Simulations on the vehicle simulation software CarSim® show that the proposed active roll control system with integrated chassis control is effective for controlling the roll motion and the yaw motion of a hybrid four-wheel-drive vehicle.