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This is a errata for 2017-01-2520.

One of the most important challenges for electronic stability control (ESC) systems is the identification and monitoring of tire rolling environment, especially actual tire-road friction parameters. The presented research considers an advanced variant of the ESC system deducing the mentioned factors based on intelligent methods as fuzzy sets. The paper includes: Overview of key issues in prototyping the algorithms of Electronic Stability Control. Case study for vehicle model. Procedures for monitoring of tire rolling environment: theoretical backgrounds, computing methods, fuzzy input and output variables, fuzzy inference systems, interface with ESC algorithm. Case study for ESC control algorithm. Examples of simulation using Hardware-in-the-Loop procedures. The proposed approach can be widely used for the next-generation of ESC devices having the close integration with Intelligent Transport Systems.

The paper introduces the results of the development of anti-lock brake system (ABS) for full electric vehicle with individually controlled near-wheel motors. The braking functions in the target vehicle are realized with electro-hydraulic decoupled friction brake system and electric motors operating in a braking mode. The proposed ABS controller is based on the direct slip and velocity control and includes several main blocks for computing of predictive (feedforward) and reactive (feedback) brake torque, wheel slip observer, slip target adaptation, and the algorithm of brake blending between friction brakes and electric motors. The functionality of developed ABS has been investigated on the HIL test rig for straight-line braking manoeuvres on different surfaces with variation of initial velocity. The obtained experimental results have been compared with the operation of baseline algorithm of a hydraulic ABS and have demonstrated a marked effect in braking performance.

The presented study demonstrates results of experimental investigations of the anti-lock braking system (ABS) performance under variation of tire inflation pressure. This research is motivated by the fact that the changes in tire inflation pressure during the vehicle operation can distinctly affect peak value of friction coefficient, stiffness and other tire characteristics, which are influencing on the ABS performance. In particular, alteration of tire parameters can cause distortion of the ABS functions resulting in increase of the braking distance. The study is based on experimental tests performed for continuous ABS control algorithm, which was implemented to the full electric vehicle with four individual on-board electric motors. All straight-line braking tests are performed on the low-friction surface where wheels are more tended to lock.

Geometric imperfections on brake rotor surface are well-known for causing periodic variations in brake torque during braking. This leads to brake judder, where vibrations are felt in the brake pedal, vehicle floor and/or steering wheel. Existing solutions to address judder often involve multiple phases of component design, extensive testing and improvement of manufacturing procedures, leading to the increase in development cost. To address this issue, active brake torque variation (BTV) compensation has been proposed for an electromechanical brake (EMB). The proposed compensator takes advantage of the EMB's powerful actuator, reasonably rigid transmission unit and high bandwidth tracking performance in achieving judder reduction.

The brake architecture of hybrid and full electric vehicle includes the distinctive function of brake blending. Known approaches draw upon the maximum energy recuperation strategy and neglect the operation mode of friction brakes. Within this framework, an efficient control of the blending functions is demanded to compensate external disturbances induced by unpredictable variations of the pad disc friction coefficient. In addition, the control demand distribution between the conventional frictional brake system and the electric motors can incur failures that compromise the frictional braking performance and safety. However, deviation of friction coefficient value given in controller from actual one can induce undesirable deterioration of brake control functions.

The paper describes a new disc brake design procedure including the ADAMS model of the air-operated brake disc mechanism and its validation against the conventional hardware. A mechanical system simulation is used in the paper to forecast the full dynamic behavior of the complex brake unit system having a lot of cooperating with each other parts.

Stability of motion, turnability, mobility and fuel consumption of all-wheel drive terrain vehicles strongly depends on engine power distribution among the front and rear driving axles and then between the left and right wheels of each axle. This paper considers kinematic discrepancy, which characterizes the difference of the theoretical velocities of the front and rear wheels, as the main factor that influences power distribution among the driving axles/wheels of vehicles with positively locked front and rear axles. The paper presents a new algorithm which enables minimization of the kinematic discrepancy factor for the improvement of AWD terrain vehicle dynamics while keeping up with minimal power losses for tire slip. Three control modes associated with gear ratio control of the front and rear driving axles are derived to provide the required change in kinematic discrepancy. Computer simulation results are presented for different scenarios of terrain and road conditions.

Development of anti-lock brake system (ABS) for motorcycles needs specific approaches to the control of movement of a wheel. The well developed ABS control principles for cars or trucks cannot be automatically applied to motorcycles. In this connection, an alternative strategy of pre-extreme ABS control has been researched and simulated. Its aim is to ensure the wheel operation in pre-extreme, stable area of “coefficient of longitudinal force - wheel slip” dependence. MATLAB software and specially created software have been used for the simulation of single-channel and two-channel ABS systems. This simulation has verified that the pre-extreme ABS algorithm guarantees the high braking efficiency and motorcycle stability consequently.

Main defect of traditional structure of the brake boosters is the necessity of an external energy source. The analysis of redistribution of power streams occurring during at braking of the automobile shows that it is possible to use the force component of the driving automobile kinetic energy for the drive of a booster (so-called kinetic booster). The power consumed by a booster is taken from power developed during brake action thereby it promotes vehicle slowing down. In the paper for the booster work the schemas of power take-off from an engine, onboard electric system, transmission, single wheel are considered. Especially for brake-by-wire systems the project of pilot management is probed. It allows applying the serial x-by-wire components both on small automobiles andon vehicle with the great load-carrying capacity and trailers.

The investigation is concerned with dependencies between a friction coefficient of the tire with a road, μ, and wheel slip, s. The analysis of μ-s-dependencies is given in the paper. The conventional approach to their presentation contains some discordance with real physical processes. On the basis of the external friction theory it is possible to offer another concept of potential μ-s-curves. The potential μ-s-curve is a function of the deformative, adhesion and transverse components of tire grip, the absolute slip velocity and the road reaction. Over the interrelation character of the given components it is possible to evaluate a current road-operational situation. In addition the recommendations for practical use of the potential μ-s-dependencies for the Systems of Active Safety are given.

The analysis of existing systems of automotive active safety (SAS) shows that the antilock braking system (ABS) is a kernel for anyone of them. However circle of the tasks, which should be decided by SAS, is complicated, and the algorithms approaches are traditionally based on threshold control. Basing on the researches of interactions within a chain ‘automobile - wheel – road’ a new so-called pre-extreme control philosophy for ABS may be offered. It is based on the discovered regularities between the tire grip and wheel slippage. For the given philosophy the family of ABS algorithms is offered which allows realising both discrete and continuous control of wheel operation.

Research and development tools for investigations of various facets of braking processes cover three major groups of devices: Dynamometer test rigs: assessment of performance, durability, life cycle and others; Tribometer test rigs: definition of parameters of friction and wear; Hardware-in-the-loop: estimation of functional properties of controlled braking. A combination of the listed devices allows to research complex phenomena related to braking systems. The presented work discusses a novel approach of test rig fusion, namely the combination of a brake dynamometer and hardware in the loop test rig. First investigations have been done during the operation of the anti-lock braking system (ABS) system to demonstrate the functionality of the approach.

This paper is part of the European OWHEEL project. It proposes a method to improve the comfort of a vehicle by adaptively controlling the Camber and Toe angles of a rear suspension. The purpose is achieved through two actuators for each wheel, one that allows to change the Camber angle and the other the Toe angle. The control action is dynamically determined based on the error between the reference angle and the actual angles. The reference angles are not fixed over time but dynamically vary during the maneuver. The references vary with the aim of maintaining a Camber angle close to zero and a Toe angle that follows the trajectory of the vehicle during the curve. This improves the contact of the tire with the road. This solution allows the control system to be used flexibly for the different types of maneuvers that the vehicle could perform. An experimentally validated sports vehicle has been used to carry out the simulations. The original rear suspension is a Trailing-arm suspension.

Battery electric vehicles (BEV) share the ability of regenerative braking since they are equipped with two independent types of deceleration devices, namely the electric motor working as a generator and the friction brakes. Correct interaction of these systems in terms of driving safety and energy efficiency is a function of the Brake Blending Control. Individual electric motors for each wheel and a decoupled brake system provides the Brake Blending with a high design flexibility that allows significant advantages regarding energy consumption, brake performance, and driving comfort. This paper is focusing on the fail behaviour and analyses the robustness and redundancy abilities of such systems against various error scenarios. For this purposes, a distributed x-in-the-loop environment, consisting of dedicated simulation and hardware testing components, is introduced.

Brake-by-wire systems are an innovative and important component of modern high-performance and also electrified vehicles. Due to their decoupled architecture, they enable driver-independent vehicle dynamics control (e.g., brake torque blending) and easy integration of assistance functionalities (e.g. Emergency Brake Assist (EBA)). On the other hand, the development of these functions can cause high costs and development effort, and testing can be critical in case of improper gain tuning. Therefore, already in the concept phase, a large part of the testing is shifted to virtual environments and simulations that allow safe and reproducible experiments without damage. Therefore, suitable and reliable models are needed to represent reality as accurately as possible. This paper deals with the modelling of a purely electrohydraulic brake-by-wire system and a hybrid system with electrohydraulic brakes on the front axle and electromechanical brakes on the rear axle.

The presented study is dedicated to the technology supporting vehicle state estimation and motion control with a concept drone, which helps the vehicle in sensing the surroundings and driving conditions. This concept allows also extending the functionality of the sensors mounted on the vehicle by replacing or including additional parameter observation channels. The paper discusses the feasibility of such a drone-vehicle interaction as well as demonstrates several design configurations. In this regard, the paper presents a general description of the proposed drone system that assists the vehicle and describes an experiment in measuring the profile of the road with a range sensor. The results obtained in the experiment are described in terms of the accuracy to be achieved using the drone and are compared with other studies, which use the methods of estimation from the sensors mounted on the vehicle.

The presented research discusses the experimental procedure developed for testing of friction brake systems installed on the modern electric vehicles. Approach of combined experimental technique utilizing hardware-in-the-loop platform and brake dynamometer is introduced. As the case study, an influence of brake lining coefficient of friction fluctuations on the anti-lock brake system (ABS) performance is investigated. The ABS algorithm is represented by the direct slip control aimed to the precise tracking of reference slip ratio by means of electric and friction brake system. Vehicle prototype is represented by RWD electric vehicle with in-wheel motors. Results, representing the investigated phenomenon, are derived using the developed combined test bench. The achieved results give a basis for further extension of standard brake testing procedures.

E-mobility is a game changer for the automotive domain. It promises significant reduction in terms of complexity and in terms of local emissions. With falling prices and recent technological advances, the second generation of electric vehicles (EVs) that is now in production makes electromobility an affordable and viable option for more and more transport mission (people, freight). Current e-vehicle platforms still present architectural similarities with respect to combustion engine vehicle (e.g., centralized motor). Target of the European project EVC1000 is to introduce corner solutions with in-wheel motors supported by electrified chassis components (brake-by-wire, active suspension) and advanced control strategies for full potential exploitation. Especially, it is expected that this solution will provide more architectural freedom toward “design-for-purpose” vehicles built for dedicated usage models, further providing higher performances.

Anti-lock braking functions of electric vehicles with individual wheel drive can be effectively realized through the operation of in-wheel or on-board motors in the pure regenerative mode or in the blending mode with conventional electro-hydraulic anti-lock braking system (ABS). The regenerative ABS has an advantage in simultaneous improvement of active safety, energy efficiency, and driving comfort. In scope of this topic, the presented work introduces results of experimental investigations on a pure electric ABS installed on an electric powered sport utility vehicle (SUV) test platform with individual switch reluctance on-board electric motors transferring torque to the each wheel through the single-speed gearbox and half-shaft. The study presents test results of the vehicle braking on inhomogeneous low-friction surface for the case of ABS operation with front electric motors.