A Neural Fuzzy Approach for Controlling Active Vehicle Suspension Systems

2003 ◽  
Author(s):  
M. B. A. Abdelhady ◽  
S. A. Alhasan
Keyword(s):  
Suspension System ◽  
Road Surface ◽  
Control Law ◽  
Error Signal ◽  
Performance Parameters ◽  
Active System ◽  
Control Laws ◽  
Body Acceleration ◽  
The Road ◽  
Neural Fuzzy

In this work, a novel neural fuzzy (NF) control scheme is introduced to design a fully active suspension system. The fuzzy part of the controller handles uncertainties, whereas the neural part learns from past events and tunes the controller to optimize the performance of the suspension system. The two-degree-of-freedom quarter-car model is used to illustrate the control strategy and to evaluate the performance parameters for sinusoidal and random road inputs. A sinusoid road surface description is first used to obtain an initial design of the NF controller. The acceleration of the sprung mass is compared with that of an ideal skyhook model to produce an error signal, e(t); this error signal, as well as Δe(t) are employed as inputs to the controller. Results obtained for this type of road input indicate that the NF active system has significant advantages over the linear quadratic regulator (LQR) active suspension system. In order to get a broader view, more realistic road descriptions and practical control laws were used. The performance parameters were computed when the road surface was presented as a random road input. The control law of the NF active system was modified to achieve a novel non-linear control (NC) strategy. This control law requires only measurement of the body acceleration and the road input displacement, and hence, it can be realized easily in practice when compared with all other control laws, including the LQR one. For a wide range of road surfaces, results show that the performance capability of this novel system is much better than that of the LQR active system. For example, the improvements, under a medium-quality road surface and a 30-m/s vehicle speed, achieved a reduction in the rms values of the ISO weighted body acceleration and the dynamic tyre load by 17% and 20% respectively.

scholarly journals Design and Kinematics Analysis of Suspension System for a Formula Society of Automotive Engineers (FSAE) Car

2021 ◽  
pp. 48-63
Author(s):  
K. Sriram ◽  
K. Anirudh ◽  
B. Jayanth ◽  
J. Anjaneyulu
Keyword(s):  
Vehicle Control ◽  
Simulation Software ◽  
Suspension System ◽  
Road Surface ◽  
Kinematics Analysis ◽  
Kinematic Simulation ◽  
Kinematic Design ◽  
The Road ◽  
Adams Simulation

The main objective of the Suspension of a vehicle is to maximize the contact between the vehicle tires and the road surface, provide steering stability and provide safe vehicle control in all conditions, evenly support the weight of the vehicle, transfer the loads to springs, and guaranteeing the comfort of the driver by absorbing and dampening shock. This paper discusses the kinematic design of a double a-arm Suspension system for an FSAE Vehicle. The hardpoint’s location can be determined using this procedure to simulate motion in any kinematic simulation software. Here, Optimum Kinematics is used as kinematic simulation software, and the results are verified using Msc Adams simulation. The method illustrated deals with the basics of Kinematics which helps to predict the characteristics of the Suspension even before simulating it in the kinematic simulation software.

Optimal Active Control of Vehicle Suspension System Including Time Delay and Preview for Rough Roads

2002 ◽  
Vol 8 (7) ◽  
pp. 967-991 ◽  
Author(s):  
Javad Marzbanrad ◽  
Goodarz Ahmadi ◽  
Yousef Hojjat ◽  
Hassan Zohoor
Keyword(s):  
Ride Comfort ◽  
Three Dimensional ◽  
Suspension System ◽  
Road Surface ◽  
Vehicle Suspension ◽  
Control Force ◽  
Preview Control ◽  
The Road ◽  
Road Surface Roughness ◽  
Vehicle Suspension System

An optimal preview control of a vehicle suspension system traveling on a rough road is studied. A three-dimensional seven degree-of-freedom car-riding model and several descriptions of the road surface roughness heights, including haversine (hole/bump) and stochastic filtered white noise models, are used in the analysis. It is assumed that contact-less sensors affixed to the vehicle front bumper measure the road surface height at some distances in the front of the car. The suspension systems are optimized with respect to ride comfort and road holding preferences including accelerations of the sprung mass, tire deflection, suspension rattle space and control force. The performance and power demand of active, active and delay, active and preview systems are evaluated and are compared with those for the passive system. The results show that the optimal preview control improves all aspects of the vehicle suspension performance while requiring less power. Effects of variation of preview time and variations in the road condition are also examined.

Modelling and Comparison of Semi-Active Control Logics for Suspension System of 8x8 Armoured Multi-Role Military Vehicle

2014 ◽  
Vol 592-594 ◽  
pp. 2165-2178 ◽  
Author(s):  
M.W. Trikande ◽  
Vinit V. Jagirdar ◽  
Muraleedharan Sujithkumar
Keyword(s):  
Active Control ◽  
Time Domain ◽  
Ride Comfort ◽  
Vertical Direction ◽  
Active Suspension ◽  
Suspension System ◽  
Road Surface ◽  
Vehicle Speed ◽  
The Road ◽  
Road Disturbance

Comparative performance of vehicle suspension system using passive, and semi-active control (on-off and continuous) has been carried out for a multi-axle vehicle under the source of road disturbance. Modelling and prediction for stochastic inputs from random road surface profiles has been carried out. The road surface is considered as a stationary stochastic process in time domain assuming constant vehicle speed. The road surface elevations as a function of time have been generated using IFFT. Semi active suspension gives better ride comfort with consumption of fraction of power required for active suspension. A mathematical model has been developed and control algorithm has been verified with the purpose/objective of reducing the unwanted sprung mass motions such as heave, pitch and roll. However, the cost and complexity of the system increases with implementation of semi-active control, especially in military domain. In addition to fully passive and fully semi-active a comparison has been made with partial semi-active control for a multi-axle vehicle to obviate the constraints. The time domain response of the suspension system using various control logics are obtained and compared. Simulations for different class of roads as defined in ISO: 8608 have been run and the ride comfort is evaluated and compared in terms of rms acceleration at CG in vertical direction (Z), which is the major contributor for ORV (Overall Ride Value) Measurement.

Optimal Design of Active and Semi-Active Suspensions Including Time Delays and Preview

1993 ◽  
Vol 115 (4) ◽  
pp. 498-508 ◽  
Author(s):  
A. Hac´ ◽  
I. Youn
Keyword(s):  
Ride Comfort ◽  
Controller Design ◽  
Piecewise Linear ◽  
Active Suspension ◽  
Front Wheel ◽  
Active System ◽  
Control Laws ◽  
The Road ◽  
Suspension Systems ◽  
And Control

Several control laws for active and semi-active suspension based on a linear half car model are derived and investigated. The strategies proposed take full advantage of the fact that the road input to the rear wheels is a delayed version of that to the front wheels, which in turn can be obtained either from the measurements of the front wheels and body motions or by direct preview of road irregularities if preview sensors are available. The suspension systems are optimized with respect to ride comfort, road holding and suspension rattle space as expressed by the mean-square-values of body acceleration (including effects of heave and pitch), tire deflections and front and rear suspension travels. The optimal control laws that minimize the given performance index and include passivity constraints in the semi-active case are derived using calculus of variation. The optimal semi-active suspension becomes piecewise linear, varying between passive and fully active system and combinations of them. The performances of active and semi-active systems with and without preview were evaluated by numerical simulation in the time and frequency domains. The results show that incorporation of time delay between the front and rear axles in controller design improves the dynamic behavior of the rear axle and control of body pitch motion, while additional preview improves front wheel dynamics and body heave.

scholarly journals Assessment of the Road Surface Condition with Longitudinal Acceleration Signal of the Car Body

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 5987
Author(s):  
Krzysztof Prażnowski ◽  
Jarosław Mamala ◽  
Michał Śmieja ◽  
Mariusz Kupina
Keyword(s):  
Surface Condition ◽  
Mean Amplitude ◽  
Road Surface ◽  
Vehicle Body ◽  
Frequency Bands ◽  
Body Acceleration ◽  
The Road ◽  
Road Roughness ◽  
Specific Frequency ◽  
The Mean

On the basis of road tests, the authors assessed the feasibility of the vehicle body acceleration values for the purposes of assessing road surface characteristics in terms of its roughness. Short-term Fourier Transform (STFT) was used for the analysis of the recorded signal. The spectra obtained in successive frequency bands demonstrate the amplitudes originating from the natural vibrations of the rolling wheel and forces resulting from the interaction with the road roughness. The article focuses on the relationships between the road roughness and the ratios of individual amplitudes in a specific frequency band of the vehicle body acceleration values. Amplitude values derived on the basis of successive windows were averaged for analogous, arbitrarily assumed local frequency bands. The value characterizing the road surface condition provided the information regarding the mean amplitude value in specific frequency ranges depending on the instantaneous velocity of the car body and the condition of the road surface on which it was moving. In cases where the road was free of any visible roughness, the obtained mean amplitude value in the analyzed spectrum window, for the adopted vehicle velocity range from 50 km h to 100 km/h, did not exceed 0.02 m/s2. It was also demonstrated that the road surface roughness leads to an increase in the mean amplitude value from 0.07 m/s2 to 0.16 m/s2.

scholarly journals Active Control of Nonlinear Suspension System Using Modified Adaptive Supertwisting Controller

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Jagat J. Rath ◽  
Kalyana C. Veluvolu ◽  
Michael Defoort
Keyword(s):  
Active Control ◽  
Ride Comfort ◽  
Sliding Mode ◽  
Active Suspension ◽  
Higher Order ◽  
Suspension System ◽  
Road Surface ◽  
Control Action ◽  
The Road ◽  
Bounded Uncertainties

The suspension system is faced with nonlinearities from the spring, damper, and external excitations from the road surface. The objective of any control action provided to the suspension is to improve ride comfort while ensuring road holding for the vehicle. In this work, a robust higher order sliding mode algorithm combining the merits of the modified supertwisting algorithm and the adaptive supertwisting algorithm has been proposed for the nonlinear active suspension system. The proposed controller is robust to linearly growing perturbations and bounded uncertainties. Simulations have been performed for different classes of road excitations and the results are presented.

Liftable Auxiliary Axle for a Multi Axle Vehicle: A Review

2009 ◽  
Author(s):  
A. Sahaya Grinspon
Keyword(s):  
Suspension System ◽  
Road Surface ◽  
Compressed Air ◽  
The Road ◽  
Current State ◽  
Load Carrying

Retractable suspension system is used to lift the auxiliary axle of a multi axle vehicle. The article summarizes the current state of knowledge of the lifting mechanisms, which are used for lifting and lowering the auxiliary axle. Various designs of liftable axle are described. To proper use of the auxiliary axle, important guidelines are given for suppliers, OEMs and customers. Several viable steerable and non-steerable liftable axles are developed with various load carrying capacities using air bellows. In these liftable axles, the air bellows expands when compressed air is supplied to the air bellows at a required pressure. The air bellows activates the lifting mechanism; thereby the tires of the auxiliary axle are lifted from the road surface. When the air is released from the air bellows, the tires are lowered to engage the road surface.

A multi-switching mode intelligent hybrid control of electro-hydraulic proportional systems

2018 ◽  
Vol 233 (1) ◽  
pp. 120-131 ◽  
Author(s):  
Xiangzhen Kong ◽  
Hasan Majumdar ◽  
Faye Zang ◽  
Shouyong Jiang ◽  
Qingzhen Wu ◽  
...  
Keyword(s):  
Control System ◽  
Fuzzy Controller ◽  
Hybrid Control ◽  
Experimental Result ◽  
Control Law ◽  
Control Laws ◽  
Proportional Systems ◽  
Switching Mode ◽  
Non Linear System ◽  
Neural Fuzzy

The electro-hydraulic proportional system is a highly non-linear system owing to the fact that the system is composed of components from different disciplines such as electric, hydraulic and mechanical disciplines. In general, a switching-based controller is suitable to the control of such a system. In this paper, a switching-based controller is proposed, which is called multi-switching mode intelligent hybrid control, for electro-hydraulic proportional systems. The novelty of the multi-switching mode intelligent hybrid control is that it integrates the PID control law, the neural-fuzzy control law, and the expert-based control law. To demonstrate the effectiveness of the proposed multi-switching mode intelligent hybrid control, both experiment and simulation were conducted. It is shown that the experimental result corresponds well with the simulation result. Further, the proposed control system was compared with the traditional ones such as PID and neural-fuzzy controller for a trajectory tracking task with an electro-hydraulic proportional, which shows that the proposed one is far superior to these traditional ones. Overall, there is evidence that the proposed multi-switching mode intelligent hybrid control is very effective. It is noted that though the idea of the switching-based control system to electro-hydraulic proportional systems may not be new, the specific integration of the member control laws along with specific control laws developed in this work to electro-hydraulic proportional systems is not reported in the literature and multi-switching mode intelligent hybrid control is potentially useful to other electro-hydraulic proportional systems.

Tire-Road Interactions — Harmony or Conflict?

1989 ◽  
Vol 17 (1) ◽  
pp. 66-84
Author(s):  
A. R. Williams
Keyword(s):  
Rolling Resistance ◽  
Major Effect ◽  
Road Surface ◽  
Interactive Effects ◽  
Central Theme ◽  
Water Drainage ◽  
The Road ◽  
Truck Tires ◽  
Road Surfaces ◽  
Tire Wear

Abstract This is a summary of work by the author and his colleagues, as well as by others reported in the literature, that demonstrate a need for considering a vehicle, its tires, and the road surface as a system. The central theme is interaction at the footprint, especially that of truck tires. Individual and interactive effects of road and tires are considered under the major topics of road aggregate (macroscopic and microscopic properties), development of a novel road surface, safety, noise, rolling resistance, riding comfort, water drainage by both road and tire, development of tire tread compounds and a proving ground, and influence of tire wear on wet traction. A general conclusion is that road surfaces have both the major effect and the greater potential for improvement.

Control Strategies for Semi-Active Lorry Suspensions

1996 ◽  
Vol 210 (2) ◽  
pp. 161-178 ◽  
Author(s):  
D Cebon ◽  
F H Besinger ◽  
D J Cole
Keyword(s):  
Linear Models ◽  
Control Strategies ◽  
Power Input ◽  
Optimum Level ◽  
Passive Damping ◽  
Control Laws ◽  
Body Acceleration ◽  
Performance Improvements ◽  
Full State Feedback ◽  
Active Damper

The optimum level of passive damping for minimizing the root mean square (r.m.s.) dynamic tyre force and r.m.s. body acceleration of a heavy vehicle is determined by testing a damper in a ‘hardware-in-the-loop’ (HiL) test rig. Two different control strategies [‘modified skyhook damping’ (MSD), and linear optimal control with full state feedback (FSF)] are investigated theoretically using linear models, and suspension force control laws are derived. These control laws, along with simple ‘on–off’ control, are then tested experimentally using a prototype semi-active damper which is controlled so as to follow the demanded force, except when power input is required. The achievable performance improvements are compared and differences between the linear theory, computer simulations and experimental performance are discussed. It is found that using FSF control, r.m.s. body acceleration and r.m.s. tyre force can be reduced simultaneously by 28 and 21 per cent of their values for optimal passive damping.

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