ADVANCED BRAKING SYSTEM CONTROL PROTOTYPING USING NETWORKED HARDWARE-IN-THE-LOOP TECHNIQUE

Control functions for the base-braking and emergency braking situations are important element of the vehicle active safety and have high requirements to robustness. The corresponding control algorithms should be reliable, provide sufficient level of system adaptiveness and be able to reject external disturbances. This demands not only the well-organized controller from the theoretical point of view, but also its systematic experimental validation. Moreover, effects and factors, which can potentially produce deterioration of braking system control functions, should be properly taken into account in the simulation and during the experiments. Another important factor is that brake control systems have a closed-loop operation with the tyre-road interaction, and its operation is accompanied by such complex effects like (i) variation of disc/pad friction coefficient and (ii) brake hysteresis. This produces strong demand on extension of the conventional testing facilities for the braking system control evaluation. Therefore, besides the part of the control system design, this paper represents possible advancement of hardware-in-the-loop testing procedure for development and validation of braking system control functions

Advanced electric vehicle components for long-distance daily trips

This paper introduces a holistic engineering approach for the design of an electric sport utility vehicle focused on the reliable capability of long-distance daily trips. This approach is targeting integration of advanced powertrain and chassis components to achieve energy-efficient driving dynamics through manifold contribution of their improved functions. The powertrain layout of the electric vehicle under discussion is designed for an e-traction axle system including in-wheel motors and the dual inverter. The main elements of the chassis layout are the electro-magnetic suspension and the hybrid brake-by-wire system with electro-hydraulic actuators on the front axle and the electro-mechanical actuators on the rear axle. All the listed powertrain and chassis components are united under an integrated vehicle dynamics and energy management control strategy that is also outlined in the paper. The study is illustrated with the experimental results confirming the achieved high performance on the electric vehicle systems level

Robust control of brake systems with decoupled architecture

Modern brake systems have the tendency to decoupled brake system design involving electric and/or electrohydraulic brake actuators. In this thesis, a corresponding brake control architecture applicable for electric and automated vehicles is proposed and includes (i) base braking, (ii) brake blending and (iii) wheel slip control functions. Main focus has been given to the robustness of continuous wheel slip control during emergency braking in high and low road friction conditions. As the solution, several control laws were designed and experimentally validated during road tests. Results obtained for three vehicle prototypes with individual on-board and in-wheel electric motors and electrohydraulic brake-by-wire system present significant improvement in braking performance and ride quality compared to the conventional wheel slip control strategies.Moderne Bremssysteme tendieren zur entkoppelten Konstruktion mit involvierten elektrischen und/oder elektrohydraulischen Aktuatoren. In der vorliegenden Arbeit ist die entsprechende Bremsregelungsarchitektur für die elektrischen und automatisierten Fahrzeuge vorgeschlagen, die beinhaltet Funktionen zur (i) primären Bremsung, (ii) gemischten Bremsung und (iii) Radschlupfregelung. Der Schwerpunkt dieser Arbeit ist auf die Robustheit der kontinuierlichen Radschlupfregelung während einer Notbremsung bei hoher und niedriger Fahrbahnreibung gelegt. Als die Lösung sind mehrere Regelungsstrategien entwickelt und experimentell validiert. Die Ergebnisse für drei Fahrzeugprototypen mit individuellen Board- und Radnabemotoren und einem elektrohydraulischen Brake-by-Wire System demonstrieren wesentliche Verbesserung der Bremsleistung und Fahrqualität im Vergleich zu den konventionellen Strategien der Radschlupfregelung

Advanced continuously variable transmissions for electric and hybrid vehicles

A brief survey of past and present continuously variable transmissions (CVT) which are potentially suitable for application with electric and hybrid vehicles is presented. Discussion of general transmission requirements and benefits attainable with a CVT for electric vehicle use is given. The arrangement and function of several specific CVT concepts are cited along with their current development status. Lastly, the results of preliminary design studies conducted under a NASA contract for DOE on four CVT concepts for use in advanced electric vehicles are reviewed

Ride blending control for electric vehicles

Vehicles equipped with in-wheel motors (IWMs) feature advanced control functions that allow for enhanced vehicle dynamics and stability. However, these improvements occur to the detriment of ride comfort due to the increased unsprung mass. This study investigates the driving comfort enhancement in electric vehicles that can be achieved through blended control of IWMs and active suspensions (ASs). The term “ride blending”, coined in a previous authors’ work and herein retained, is proposed by analogy with the brake blending to identify the blended action of IWMs and ASs. In the present work, the superior performance of the ride blending control is demonstrated against several driving manoeuvres typically used for the evaluation of the ride quality. The effectiveness of the proposed ride blending control is confirmed by the improved key performance indexes associated with driving comfort and active safety. The simulation results refer to the comparison of the conventional sport utility vehicle (SUV) equipped with a passive suspension system and its electric version provided with ride blending control. The simulation analysis is conducted with an experimentally validated vehicle model in CarMaker® and MATLAB/Simulink co-simulation environment including high-fidelity vehicle subsystems models

Ride Blending Control for Electric Vehicles

Vehicles equipped with in-wheel motors (IWMs) feature advanced control functions that allow for enhanced vehicle dynamics and stability. However, these improvements occur to the detriment of ride comfort due to the increased unsprung mass. This study investigates the driving comfort enhancement in electric vehicles that can be achieved through blended control of IWMs and active suspensions (ASs). The term &ldquo ride blending&rdquo , coined in a previous authors&rsquo work and herein retained, is proposed by analogy with the brake blending to identify the blended action of IWMs and ASs. In the present work, the superior performance of the ride blending control is demonstrated against several driving manoeuvres typically used for the evaluation of the ride quality. The effectiveness of the proposed ride blending control is confirmed by the improved key performance indexes associated with driving comfort and active safety. The simulation results refer to the comparison of the conventional sport utility vehicle (SUV) equipped with a passive suspension system and its electric version provided with ride blending control. The simulation analysis is conducted with an experimentally validated vehicle model in CarMaker&reg and MATLAB/Simulink co-simulation environment including high-fidelity vehicle subsystems models. Document type: Articl

Rolling stock technology for the future

The paper presents a vision for future rolling stock with a timescale of 30-50 years to identify the key changes that are likely to be influential, in particular to meet the challenges associated with the UK’s ambitious technical strategy. Overall it suggests the authors’ vision for future rolling stock, not necessarily as a perfect prediction, but certainly to highlight the main possibilities