Modeling an Active Vehicle Suspension System With Application of Digital Displacement Pump Motor

Author(s):  
Xubin Song

Vehicle suspension design can be simplified by using compressible fluid (CF) based struts. One single CF strut can provide both spring and damping force instead of two independent components of spring and shock absorber in a traditional vehicle suspension system. With the application of a digital displacement pump motor (DDPM) to modulate the fluid amount in CF struts, a hydraulic based active suspension can be developed. Each vehicle suspension corner (i.e., CF strut) can be linked to (at least) one cylinder of a multiple cylinder DDPM. Each cylinder has two poppet valves to allow exchanging flow between strut and accumulator. Those valves are actively controlled according to a properly designed control strategy. Thus DDPM can regulate the fluid flow to/from the CF struts to create a desired strut force at each suspension corner. This paper focuses on elaborating this novel active suspension using CFS and DDPM, and then presents a model that can well capture the macro-behavior of this new active suspension.

2016 ◽  
Vol 20 (5) ◽  
pp. 1725-1739 ◽  
Author(s):  
Miroslav Demic ◽  
Djordje Diligenski

Dynamic simulation, based on modelling, has a significant role during to the process of vehicle development. It is especially important in the first design stages, when relevant parameters are to be defined. Shock absorber, as an executive part of a semi-active suspension system, is exposed to thermal loads which can lead to its damage and degradation of characteristics. Therefore, this paper attempts to analyze a conversion of mechanical work into heat energy by use of a method of dynamic simulation. The issue of heat dissipation from the shock absorber has not been taken into consideration.


Author(s):  
Maria Aline Gonçalves ◽  
Rodrigo Tumolin Rocha ◽  
Frederic Conrad Janzen ◽  
José Manoel Balthazar ◽  
Angelo Marcelo Tusset

2019 ◽  
Vol 39 (3) ◽  
pp. 787-802 ◽  
Author(s):  
Mingde Gong ◽  
Hao Chen

A semi-active suspension variable damping control strategy for heavy vehicles is proposed in this work. First, a nine-degree-of-freedom model of a semi-active suspension of heavy vehicles and a stochastic road input mathematical model are established. Second, using a 1/6 vehicle as an example, a semi-active suspension system with damping that can be adjusted actively is designed using proportional relief and throttle valves. The damping dynamic characteristics of the semi-active suspension system and the time to establish the damping force are studied through a simulation. Finally, a variable damping control strategy based on an actuator motion state is proposed to adjust the damping force of the semi-active suspension system actively and therefore satisfy the vibration reduction requirements of different roads. Results show that the variable damping control suspension can substantially improve vehicle ride comfort and handling stability in comparison with a passive suspension.


Author(s):  
A.S. Emam ◽  
H. Metered ◽  
A.M. Abdel Ghany

In this paper, an optimal Fractional Order Proportional Integral Derivative (FOPID) controller is applied in vehicle active suspension system to improve the ride comfort and vehicle stability without consideration of the actuator. The optimal values of the five gains of FOPID controller to minimize the objective function are tuned using a Multi-Objective Genetic Algorithm (MOGA). A half vehicle suspension system is modelled mathematically as 6 degrees-of-freedom mechanical system and then simulated using Matlab/Simulink software. The performance of the active suspension with FOPID controller is compared with passive suspension system under bump road excitation to show the efficiency of the proposed controller. The simulation results show that the active suspension system using the FOPID controller can offer a significant enhancement of ride comfort and vehicle stability.


Sign in / Sign up

Export Citation Format

Share Document