A control strategy for efficient slip ratio regulation of a pneumatic brake system for commercial vehicles

This paper presents a control strategy for efficient slip ratio regulation of a pneumatic brake system for commercial vehicles. A model-based estimator for brake pressure estimation has been developed. The braking torque applied to the wheel has been computed using the estimated brake pressure for the control of the wheel slip both in braking and traction situations. The vehicle velocity and wheel slip ratio estimation algorithms have been designed using only wheel speed sensors. The proposed slip regulation algorithm has also been successfully implemented for the antilock braking system (ABS) and traction control system (TCS). In ABS, the slip ratio and wheel acceleration are stabilized by a limit cycle control of the braking pressure. The TCS has been implemented by combining engine torque control and pneumatic brake pressure control. The brake controller is based on the valve switched control that incorporates the wheel dynamics and valve on/off characteristics. The ABS and TCS algorithms are integrated into the slip regulation algorithm to reduce the computation load of an Electrical Control Unit (ECU). Four-wheel independent slip monitoring and slip ratio control algorithms have been implemented on the ECU, and their performance has been investigated via both computer simulations and vehicle tests. Both results show that the proposed algorithms enhance the acceleration and braking performance without vehicle acceleration information. Moreover, the proposed split-mu strategy has improved the lateral stability during braking, and the acceleration performance during accelerating on the split-mu road. It has been shown via vehicle tests that, compared to the reference commercial algorithm, the braking distance was reduced by more than 4% on the split-mu and low-mu roads, and the acceleration performance was improved by 7.9% on the split-mu road.

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Experimental design of control strategy based on brake pressure changes on wet and slippery surfaces of rough road for variable damper setting during braking with activated anti-lock brake system

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407012443443 ◽

2012 ◽

Vol 226 (10) ◽

pp. 1303-1324 ◽

Cited By ~ 4

Author(s):

Hakan Koylu ◽

Ali Cinar

Keyword(s):

Control Strategy ◽

Electronic Control Unit ◽

Control Unit ◽

Pressure Change ◽

Brake System ◽

Damping Capacity ◽

Passenger Cars ◽

The Road ◽

Brake Pressure ◽

Braking Distance

In this study, the control strategy based on experimental study is established for a variable damper setting with activated anti-lock brake system. For this, anti-lock brake system braking tests have been conducted by using hard, medium–hard and soft dampers on a rough road which has wet and slippery surfaces. In anti-lock brake system tests, brake pressure has been measured. The brake pressure increasing and decreasing rates have been obtained using measured brake pressure. The control strategy has been designed by using threshold values acquired from these test results related to brake pressure. For this, firstly, the brake pressure change thresholds of damper providing the shortest braking distance are determined. Then, the damping capacity stage rules are designed by depending on the brake pressure thresholds corresponding to the road conditions. The control strategy performance has been evaluated during transitions between wet and slippery roads. The results show that this control strategy is effectively applied to passenger cars without any change in electronic control unit configuration of anti-lock brake system. For this control strategy, it is considerably important that the damper setting to provide the shortest braking distance is detected.

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A Research on Anti-Slip Regulation for 4WD Electric Vehicle with In-Wheel Motors

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.347-350.753 ◽

2013 ◽

Vol 347-350 ◽

pp. 753-757

Author(s):

Li Zhou ◽

Lu Xiong ◽

Zhuo Ping Yu

Keyword(s):

Control Strategy ◽

Sliding Mode ◽

Traction Force ◽

Slip Rate ◽

Control Effect ◽

Wheel Slip ◽

Slip Ratio ◽

Tire Force ◽

Optimal Slip Ratio ◽

Electrical Vehicle

This paper proposes a wheel slip control strategy for 4WD Electrical Vehicle with In-wheel Motors. In the first part of this paper, a brief introduction of sliding mode control for acceleration slip regulation is given. Consider that its control effect varies with road conditions, another algorithm which can automatically adapt to different roads is designed. This method takes advantage of the peculiarity of the longitudinal static tire force curve and regulates wheel slip ratio to the detected optimal value, aiming to maximize the traction force while preserving sufficient lateral tire force. Simulation results show that the slip rate can be regulated to a value around the optimal slip ratio, and the driving torque is very close to the maximum transmissible torque. The control strategy achieves stronger stability, shorter driving distance and hence better control performance.

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Effects of sliding surface on the performances of adaptive sliding mode slip ratio controller for a HEV

Archives of Control Sciences ◽

10.2478/acsc-2013-0011 ◽

2013 ◽

Vol 23 (2) ◽

pp. 187-203 ◽

Cited By ~ 2

Author(s):

Basanta Kumar Dash ◽

Bidyadhar Subudhi

Keyword(s):

Hybrid Electric Vehicle ◽

Sliding Mode ◽

Nonlinear Function ◽

Control Force ◽

Sliding Surface ◽

Wheel Slip ◽

Slip Ratio ◽

Important Concern ◽

Control Paradigm ◽

Antilock Braking System

Slip ratio control of a ground vehicle is an important concern for the development of antilock braking system (ABS) to avoid skidding when there is a transition of road surfaces. In the past, the slip ratio models of such vehicles were derived to implement ABS. It is found that the dynamics of the hybrid electric vehicle (HEV) is nonlinear, time varying and uncertain as the tire-road dynamics is a nonlinear function of road adhesion coefficient and wheel slip. Sliding mode control (SMC) is a robust control paradigm which has been extensively used successfully in the development of ABS of a HEV. But the SMC performance is influenced by the choice of sliding surface. This is due to the discontinuous switching of control force arising in the vicinity of the sliding surface that produces chattering. This paper presents a detailed study on the effects of different sliding surfaces on the performances of sliding mode based adaptive slip ratio control applied to a HEV.

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Influence of Tire Parameters on ABS Performance

Tire Science and Technology ◽

10.2346/tire.17.450203 ◽

2017 ◽

Vol 45 (2) ◽

pp. 121-143 ◽

Cited By ~ 4

Author(s):

Stefano Arrigoni ◽

Federico Cheli ◽

Paolo Gavardi ◽

Edoardo Sabbioni

Keyword(s):

Degrees Of Freedom ◽

Test Bench ◽

Control Unit ◽

Experimental Tests ◽

Control Logic ◽

Relaxation Length ◽

Slip Ratio ◽

Braking System ◽

Longitudinal Stiffness ◽

Antilock Braking System

ABSTRACT The antilock braking system (ABS) is an active control system, which prevents the wheels from locking-up during severe braking. The ABS control cycle rapidly modulates braking pressure at each wheel mainly based on tire peripheral acceleration. Significant wheel speed oscillations and consequent fast variations of tire longitudinal slip are a consequence, which, in turn, produce a corresponding variation of tire longitudinal force according to the ABS control cycle. Clearly, tire characteristics, namely, tire peak friction (regulating maximum vehicle deceleration), longitudinal stiffness, optimal slip ratio, curvature factor (regulating the position of the peak of μ-slip curve and the subsequent drop), and relaxation length (accounting for tire dynamic response) may significantly influence ABS performance. The aim of the present paper is to evaluate the effect of the main tire parameters on ABS performance. This task is, however, very challenging, since tire characteristics are intrinsically related, and the analysis involves interaction between tires, vehicle, and ABS control logic. A methodology based on the hardware-in-the-loop (HiL) technique is used. This approach was selected to overcome limitations of numerical simulations or difficulties related to the execution of on-road experimental tests (repeatability, costs, etc.). The developed HiL test bench includes all the physical elements of the braking system of a vehicle (comprising the ABS control unit) and a 14 degrees of freedom (dofs) vehicle model, which are synchronized by a real-time board. With the developed HiL test bench, a sensitivity analysis was carried out to assess the influence of tire peak friction, longitudinal stiffness, and relaxation length on ABS performance, evaluated in terms of braking distance, mean longitudinal acceleration, and energy distribution.

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Backstepping Fuzzy Sliding Mode Control for the Antiskid Braking System of Unmanned Aerial Vehicles

Electronics ◽

10.3390/electronics9101731 ◽

2020 ◽

Vol 9 (10) ◽

pp. 1731

Author(s):

Xi Zhang ◽

Hui Lin

Keyword(s):

Sliding Mode Control ◽

Unmanned Aerial Vehicles ◽

Control Strategy ◽

Sliding Mode ◽

Pressure Control ◽

Slip Ratio ◽

Fuzzy Sliding Mode Control ◽

Braking System ◽

Mode Control ◽

Fuzzy Sliding Mode

This paper proposes a backstepping fuzzy sliding mode control method for the antiskid braking system (ABS) of unmanned aerial vehicles (UAVs). First, the longitudinal dynamic model of the UAV braking system is established and combined with the model of the electromechanical actuator (EMA), based on reasonable simplification. Subsequently, to overcome the higher-order nonlinearity of the braking system and ensure the lateral stability of the UAV during the braking process, an ABS controller is designed using the barrier Lyapunov function to ensure that the slip ratio can track the reference value without exceeding the preset range. Then, a power fast terminal sliding mode control algorithm is adopted to realize high-performance braking pressure control, which is required in the ABS controller, and a fuzzy corrector is established to improve the dynamic adaptation of the EMA controller in different braking pressure ranges. The experimental results show that the proposed braking pressure control strategy can improve the servo performance of the EMA, and the hardware in loop (HIL) experimental results indicate that the proposed slip ratio control strategy demonstrates a satisfactory performance in terms of stability under various runway conditions.

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Research on a Novel Electro-Hydraulic Brake System and Pressure Control Strategy

10.4271/2018-01-0764 ◽

2018 ◽

Cited By ~ 1

Author(s):

Haizhen Liu ◽

Rui He ◽

Weiwen Deng ◽

Shun Yang ◽

Jian Wu ◽

...

Keyword(s):

Control Strategy ◽

Pressure Control ◽

Brake System ◽

Hydraulic Brake

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Asymmetric Barrier Lyapunov Function-Based Wheel Slip Control for Antilock Braking System

International Journal of Aerospace Engineering ◽

10.1155/2015/917807 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Xiaolei Chen ◽

Zhiyong Dai ◽

Hui Lin ◽

Yanan Qiu ◽

Xiaogeng Liang

Keyword(s):

Wheel Slip ◽

Slip Ratio ◽

Braking System ◽

Aircraft Landing ◽

Optimal Slip Ratio ◽

Antilock Braking System ◽

Control Schemes ◽

Slip Region ◽

Antilock Braking ◽

Hardware In Loop

As an important device of the aircraft landing system, the antilock braking system (ABS) has a function to avoid aircraft wheels self-locking. To deal with the strong nonlinear characteristics, complex nonlinear control schemes are applied in ABS. However, none of existing control schemes focus on the braking operating status, which directly reflects wheels self-locking degree. In this paper, the braking operating status region is divided into three regions: the healthy region, the light slip region, and the deep slip region. An ABLF-based wheel slip controller is proposed for ABS to constrain the braking system operating status in the healthy region and the light slip region. Therefore the ABS will be prevented from operating in the deep slip region. Under the proposed control scheme, self-locking is avoided completely and zero steady state error tracking of the wheel optimal slip ratio is implemented. The Hardware-In-Loop (HIL) experiments have validated the effectiveness of the proposed controller.

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A novel pressure control strategy of an electro-hydraulic brake system via fusion of control signals

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407018821016 ◽

2019 ◽

Vol 233 (13) ◽

pp. 3342-3357 ◽

Cited By ~ 6

Author(s):

Wei Han ◽

Lu Xiong ◽

Zhuoping Yu

Keyword(s):

Control Strategy ◽

Sliding Mode ◽

Pressure Control ◽

Tracking Performance ◽

Brake System ◽

Automotive Application ◽

Friction Compensation ◽

Hydraulic Brake ◽

Model Based ◽

Control Signals

With the development of electro-hydraulic brake system in the automotive application, pressure control is at the top of a brake system engineer’s agenda. This work focuses on the development of a pressure-loop controller for a motor-type electro-hydraulic brake system, which is composed of an electro-mechanical actuator and a hydraulic link. The pressure control issue of motor-type electro-hydraulic brake system is influenced intensely by the nonlinearities (i.e. friction) and uncertainties (e.g. temperature variation, brake pad wear, and so on) of the system and by the very demanding performance specifications (i.e. supporting cooperative work with hydraulic control unit of anti-lock brake system). The pressure control of motor-type electro-hydraulic brake system is investigated, and a novel pressure–based control strategy via fusion of control signals is proposed to improve the pressure tracking performance. The control strategy comprises online model–based friction compensation, online dither–based friction compensation, and feedback control. Four original contributions make this work distinctive from the existing relevant literature. Selecting the Coulomb+viscous friction model can maximize to reduce difficulty of parameter identification and Stribeck effects detection based on maintaining the pressure tracking accuracy. Thanks to the model-based friction compensation torque, the signal magnitude of dither-based friction compensation torque can be decreased so that the vehicle comfort can be improved. The compensation parameters of both the model-based and dither-based friction compensation can be online modified according to the operating point of system. The robustness of the fusion controller is enhanced by employing the sliding mode control algorithm with conditional integrator. The performance of the proposed control strategy is evaluated by hardware-in-the-loop-simulation and vehicle experiment in typical braking situations. The experimental results with fusion control show improved pressure tracking performance in comparison with that without fusion control.

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