A major purpose of any vehicle suspension system is to isolate the body from roadway unevenness disturbances. On rough roads or at very high speeds on smoother roads, suspension deflection may become large enough to cause frequent bottoming, thus causing a severe degradation of isolation. Variable parameter suspensions are optimized to use the available suspension deflection to provide maximum isolation. Broadband stochastic roadway inputs at several intensity levels are applied to a quarter car model and the suspension parameters are optimized to find the best possible isolation under the (equality) constraint that the rms (root mean square) suspension deflection is a constant value in every case. From these results, improvements can be designed on the basis of measured suspension travel signals. Five types of suspension systems are investigated. These systems are called the fully active, the limited active, the optimal passive, the actively damped, and the variable damper systems. Comparisons are made among these systems in terms of rms response, frequency domain predictions and eigen-frequency behavior as functions of disturbance intensity. The results show that such an adaptation philosophy would work well for moderate and high roadway intensities. For very smooth roads, forcing the suspension system to provide a specific rms travel does not produce a useful result, because at low disturbance intensities, the normal tire force variation becomes unnecessarily large as the system is forced to maintain constant rms suspension deflection. The fully active suspension system provides much better body isolation than the other types with or without equality constraint. Finally, the fully active system requires minimum suspension control force to maintain constant suspension travel compared with the other types of suspension considered.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Optimal control of vehicle random vibration with constrained suspension deflection


    Additional title:

    Optimale Kontrolle der zufälligen Fahrzeugvibrationen durch Begrenzung des Federwegs


    Contributors:

    Published in:

    Publication date :

    1996


    Size :

    18 Seiten, 11 Bilder, 1 Tabelle, 27 Quellen




    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English





    Load-Deflection Characteristics of Vehicle Suspension Systems

    Livermore, Donald F. | SAE Technical Papers | 1967


    Comfort Improvement of an Adaptive Vehicle Suspension via Pointwise-Constrained Optimal Control

    Palomares, Eduardo / Felix, Miguel / Morales, Angel L. et al. | TIBKAT | 2020


    Comfort Improvement of an Adaptive Vehicle Suspension via Pointwise-Constrained Optimal Control

    Palomares, Eduardo / Felix, Miguel / Morales, Angel L. et al. | Springer Verlag | 2020


    Constrained optimal control of vibration dampers

    Kasturi, P. | Online Contents | 1998