The Experts below are selected from a list of 31080 Experts worldwide ranked by ideXlab platform

D Cebon - One of the best experts on this subject based on the ideXlab platform.

  • design concept for an alternative Heavy Vehicle slip control brake actuator
    2013
    Co-Authors: Jonathan I Miller, F Kienhofer, D Cebon
    Abstract:

    Heavy Vehicles have sluggish pneumatic brake actuators that limit the cycling bandwidth of their antilock braking systems. In order to implement more effective braking controllers, the conventional actuation systems must be redesigned. This paper introduces a novel actuator that features high bandwidth, binary actuated valves placed directly on the brake chamber. A preliminary look at the effect of slip control bandwidth on the compromise between stopping distance and air usage is first presented. One-dimensional flow theory is then combined with simple thermodynamic arguments to describe charging and discharging of a brake chamber. The resulting equations are linearized and used to design a closed-loop pressure controller for the actuator. Finally, the performance of the valves is presented with respect to their steadystate accuracy and time delay.

  • modelling of hydraulic regenerative braking systems for Heavy Vehicles
    Proceedings of the Institution of Mechanical Engineers Part D: Journal of Automobile Engineering, 2013
    Co-Authors: William Jb Midgley, H Cathcart, D Cebon
    Abstract:

    A hydraulic regenerative braking system for an articulated Heavy Vehicle is modelled for an idealised urban driving cycle, consisting of one stop and start from 30 mile/h, in a distance of 700 m. T...

  • implementation of semi active damping on a tri axle Heavy Vehicle suspension
    Proceedings of the Institution of Mechanical Engineers Part D: Journal of Automobile Engineering, 2008
    Co-Authors: R L Roebuck, D Cebon
    Abstract:

    AbstractA semi-active truck damper was developed in conjunction with a commercial shock absorber manufacturer. A linearized damper model was developed for control system design purposes. Open- and closed-loop damper force tracking control was implemented, with tests showing that an open-loop approach gave the best compromise between response speed and accuracy.A hardware-in-the-loop test facility was used to investigate performance of the damper when combined with a simulated quarter-car model. The input to the Vehicle model was a set of randomly generated road profiles, each profile traversed at an appropriate speed. Modified skyhook damping tests showed a simultaneous improvement over the optimum passive case of 13 per cent in vertical body acceleration and 8 per cent in dynamic tyre forces.Full-scale Vehicle tests of the damper on a Heavy tri-axle trailer were carried out. Implementation of modified skyhook damping yielded a simultaneous improvement over the optimum passive case of 8 per cent in vertic...

  • design concept for an alternative Heavy Vehicle abs system
    Vehicle System Dynamics, 2008
    Co-Authors: F Kienhofer, Jonathan I Miller, D Cebon
    Abstract:

    This paper investigates the use of slip control on Heavy Vehicles to reduce stopping distances and compressed air usage in an emergency stop. A hardware-in-the-loop (HiL) rig has been developed to investigate slip control. The hardware includes an air receiver, anti-lock braking system (ABS) or slip-control modulator, brake actuator and brake calliper. The braked wheel and Vehicle dynamics are simulated on a micro-processor. A gain-scheduled slip controller using the same pneumatic actuation as used by conventional ABS is developed. The slip control strategy increases the mean fully developed deceleration by 6% and halves the air usage compared to the ABS strategy on the HiL rig. The transient performance of the slip controller is poor due to the sluggish response of the ABS valves, causing a 10% increase in stopping distance. A novel fast-acting brake actuator design is described. Simulations of the new actuator implementing slip control show an improvement of 10% in stopping distance performance and 30%...

  • analytical redundancy techniques for fault detection in an active Heavy Vehicle suspension
    Vehicle System Dynamics, 2004
    Co-Authors: B P Jeppesen, D Cebon
    Abstract:

    This paper describes the design and implementation of an intelligent fault monitoring system for a prototype Heavy Vehicle active suspension system. A controller architecture has been designed, to facilitate safe start up and shutdown of the active control. This paper develops a method for monitoring the complete system, by dividing it into submodels which are more straightforward to analyse. The aim is to define a practical method for detecting faults, taking into account the nonlinearities in the real Vehicle.

Péter Gáspár - One of the best experts on this subject based on the ideXlab platform.

  • enhancing roll stability of Heavy Vehicle by lqr active anti roll bar control using electronic servo valve hydraulic actuators
    Vehicle System Dynamics, 2017
    Co-Authors: Olivier Sename, Luc Dugard, Péter Gáspár
    Abstract:

    Rollover of Heavy Vehicle is an important road safety problem world-wide. Although rollovers are relatively rare events, they are usually deadly accidents when they occur. The roll stability loss i...

  • Active anti-roll bar control using electronic servo valve hydraulic damper on single unit Heavy Vehicle
    IFAC-PapersOnLine, 2016
    Co-Authors: Van Tan Vu, Luc Dugard, Olivier Sename, Péter Gáspár
    Abstract:

    Rollover is a very serious problem for Heavy Vehicle safety, which can result in large financial and environmental consequences. In order to improve roll stability, most of modern Heavy Vehicles are equipped with passive anti-roll bars to reduce roll motion during cornering or riding on uneven roads. This paper introduces the active anti-roll bars designed by finding an optimal control based on a linear quadratic regulator (LQR). Four electronic servo-valve hydraulic dampers are modelled and applied on a yaw-roll model of a single unit Heavy Vehicle. The control signal is the current entering the electronic servo-valve and the output of this actuator is the damping force generated by the hydraulic damper. Simulation results are obtained and compared in three different situations: without anti-roll bars, with passive anti-roll bars and with active anti-roll bars. It is shown that the use of two active (front and rear) anti-roll bars drastically improves the behaviour of the single unit Heavy Vehicle.

Liyen Chang - One of the best experts on this subject based on the ideXlab platform.

  • exploring contributory factors to highway accidents a nonparametric multivariate adaptive regression spline approach
    Journal of Transportation Safety & Security, 2017
    Co-Authors: Liyen Chang
    Abstract:

    ABSTRACTPoisson and negative binomial regression models have been commonly applied to identify the significant factors that affect accident frequency on highways or at intersections. This study explores the application of an alternate method, the nonparametric multivariate adaptive regression spline (MARS) technique, to identify the effects of highway geometric characteristics, traffic factors, and environmental conditions on the frequency of highway accidents. The 2007 to 2008 accident data for National Freeway 1 in Taiwan were collected to develop MARS models. Results indicate that horizontal alignment, vertical alignment, average daily traffic volume (ADT), Heavy Vehicle ADT, and precipitation all have nonlinear effects on highway accidents.

  • analysis of freeway accident frequency using multivariate adaptive regression splines
    Procedia Engineering, 2012
    Co-Authors: Liyen Chang, Hsingchung Chu, Dajie Lin, Pei Lui
    Abstract:

    Abstract This study applies nonparametric multivariate adaptive regression splines (MARS) modeling technique to explore the effects of nonbehavior factors including highway geometrics characteristics, traffic factors as well as environmental conditions on freeway accidents. 2007-2008 accident data of National Freeway 1 in Taiwan were collected for analysis. The results indicate that horizontal alignment, vertical alignment, average daily traffic volume (ADT), Heavy Vehicle ADT and annual precipitation have are nonlinear effects on freeway accidents.

Olivier Sename - One of the best experts on this subject based on the ideXlab platform.

  • enhancing roll stability of Heavy Vehicle by lqr active anti roll bar control using electronic servo valve hydraulic actuators
    Vehicle System Dynamics, 2017
    Co-Authors: Olivier Sename, Luc Dugard, Péter Gáspár
    Abstract:

    Rollover of Heavy Vehicle is an important road safety problem world-wide. Although rollovers are relatively rare events, they are usually deadly accidents when they occur. The roll stability loss i...

  • Active anti-roll bar control using electronic servo valve hydraulic damper on single unit Heavy Vehicle
    IFAC-PapersOnLine, 2016
    Co-Authors: Van Tan Vu, Luc Dugard, Olivier Sename, Péter Gáspár
    Abstract:

    Rollover is a very serious problem for Heavy Vehicle safety, which can result in large financial and environmental consequences. In order to improve roll stability, most of modern Heavy Vehicles are equipped with passive anti-roll bars to reduce roll motion during cornering or riding on uneven roads. This paper introduces the active anti-roll bars designed by finding an optimal control based on a linear quadratic regulator (LQR). Four electronic servo-valve hydraulic dampers are modelled and applied on a yaw-roll model of a single unit Heavy Vehicle. The control signal is the current entering the electronic servo-valve and the output of this actuator is the damping force generated by the hydraulic damper. Simulation results are obtained and compared in three different situations: without anti-roll bars, with passive anti-roll bars and with active anti-roll bars. It is shown that the use of two active (front and rear) anti-roll bars drastically improves the behaviour of the single unit Heavy Vehicle.

Gáspár Péter - One of the best experts on this subject based on the ideXlab platform.

  • Enhancing roll stability of Heavy Vehicle by LQR active anti-roll bar control using electronic servo-valve hydraulic actuators
    'Informa UK Limited', 2017
    Co-Authors: Vu Van-tan, Sename Olivier, Dugard Luc, Gáspár Péter
    Abstract:

    International audienceRollover of Heavy Vehicle is an important road safety problem worldwide. Although rollovers are relatively rare events, they are usually deadly accidents when they occur. The roll stability loss is the main cause of rollover accidents in which Heavy Vehicles are involved. In order to improve the roll stability, most of modern Heavy Vehicles are equipped with passive anti-roll bars to reduce roll motion during cornering or riding on uneven roads. However these may be not sufficient to overcome critical situations. This paper introduces the active anti-roll bars made of four electronic servo-valve hydraulic actuators, which are modelled and integrated in a yaw-roll model of a single unit Heavy Vehicle. The control signal is the current entering the electronic servo-valve and the output is the force generated by the hydraulic actuator. The active control design is achieved solving a linear optimal control problem based on the Linear Quadratic Regulator (LQR) approach. A comparison of several LQR controllers is provided to allow for tackling the considered multi-objective problems. Simulation results in frequency and time domains show that the use of two active anti-roll bars (front and rear axles) drastically improves the roll stability of the single unit Heavy Vehicle compared with the passive anti-roll bar