Optimal control for semi-active suspension with inerter

The benefits of the inerter in passive suspension have been well demonstrated. To investigate suspension performances with the inerter in semi-active suspension, eight well studied passive suspension configurations with a parallel connection to a variable shock absorber are analyzed in this paper. By applying the optimal control theory, an optimal solution for each configuration is obtained and numerically solved by the forward/backward sweep method. The result shows that under the considered performance measure, the use of inerter can improve ride comfort in general, where the effect can even be significant for some specific configurations, but has no obvious advantage in road holding and suspension travel performance compared with the conventional semi-active suspension. © 2012 Chinese Assoc of Automati.published_or_final_versio

A Methodology for Optimal Semi-Active Suspension Systems Performance Evaluation

International audienceThis paper concerns the study of the optimal performance computation of a semi-active suspension evaluated in terms of comfort and handling performances. To this aim the semi-active suspension system is described as a quartercar model, equipped with a controllable damper, providing an effective representation of the semi-active suspension dynamics. The passive suspension presents dual performances: at low frequency the better comfort performances are ensured by a high damped suspension, whereas the best comfort damping is low at mid and high frequency. The handling performance is perfectly the opposite. This study highlights how this trade-off can be overcome with an optimal control of damping and how the best performances in terms of comfort are reflected in terms of handling and vice verse. The main result of this paper is to propose a methodology allowing for evaluation of handling and comfort lower theoretical filtering bounds, which can be used as a benchmark for any semi-active control design

A Methodology for Optimal Semi-Active Suspension Systems Performance Evaluation

International audienceThis paper concerns the study of the optimal performance computation of a semi-active suspension evaluated in terms of comfort and handling performances. To this aim the semi-active suspension system is described as a quartercar model, equipped with a controllable damper, providing an effective representation of the semi-active suspension dynamics. The passive suspension presents dual performances: at low frequency the better comfort performances are ensured by a high damped suspension, whereas the best comfort damping is low at mid and high frequency. The handling performance is perfectly the opposite. This study highlights how this trade-off can be overcome with an optimal control of damping and how the best performances in terms of comfort are reflected in terms of handling and vice verse. The main result of this paper is to propose a methodology allowing for evaluation of handling and comfort lower theoretical filtering bounds, which can be used as a benchmark for any semi-active control design

Approche LPV pour la commande robuste de la dynamique des véhicules (amélioration conjointe du confort et de la sécurité)

Ce travail concerne le développement de méthodes de commandes avancées pour les suspensions automobiles afin d'améliorer la tenue de route des véhicules et le confort des passagers, tout en respectant les contraintes technologiques liées aux actionneurs de suspension (passivité, non-linéarités, limite structurelle). Dans la 1ère partie, nous proposons deux schémas de commande par approche LPV polytopique (Linéaire à Paramètre Variant) et Stabilisation Forte (Strong Stabilization) avec optimisation par algorithme génétique pour résoudre les conflits confort/tenue de route et confort/débattement de suspension. Dans la 2ème partie, pour résoudre le problème complet de commande de suspensions semi-actives, nous développons d'abord une stratégie générique pour les systèmes LPV généraux soumis à la saturation des actionneurs et à des contraintes d'état. Le problème est étudié sous la forme de résolution d'inégalités linéaires matricielles (LMI) qui permettent de synthétiser un contrôleur LPV et un gain anti wind-up garantissant la stabilité et la performance du système en boucle fermée. Ensuite, cette stratégie est appliquée au cas de la commande des suspensions semi-actives. Les méthodes proposées sont validées par une évaluation basée sur un critère industriel et des simulations effectuées sur un modèle non-linéaire de quart de véhicule.This work concerns the development of advanced control methods for automotive suspensions to improve road holding and passenger comfort, while satisfying the technological constraints related to the suspension actuators (passivity, nonlinearity, structural limit). In the first part, we propose two control schemes by polytopic LPV (Linear Parameter Varying) approach and by Strong Stabilization with genetic algorithm optimization to solve the comfort/handling and comfort/suspension travel conflits. In the second part, to solve the full semi-active suspension problem, we develop first a generic strategy for general LPV systems subject to actuator saturation and state constraints. The problem is studied in the form of resolution matrix of linear inequalities (LMI) that allows synthesizing an LPV controller and an anti-windup gain to ensure the stability and performance of the closed-loop system. Second, the theoretical result is applied to the case of semi-active suspension control. The proposed methods are validated by an evaluation based on an industrial standard and simulations on a nonlinear quarter vehicle model.SAVOIE-SCD - Bib.électronique (730659901) / SudocGRENOBLE1/INP-Bib.électronique (384210012) / SudocGRENOBLE2/3-Bib.électronique (384219901) / SudocSudocFranceF