A New Lumped-Mass Vehicle Ride Model Considering Body Flexibility

2006 ◽  
Author(s):  
Avesta Goodarzi ◽  
Amir Jalali
Keyword(s):  
Ride Comfort ◽  
Vehicle Body ◽  
Total Quality ◽  
Lumped Mass ◽  
Quarter Car Model ◽  
Car Model ◽  
Rigid Model ◽  
Forced Vibration Analysis ◽  
Comparison Of The Results ◽  
Natural Frequency Analysis

Ride comfort is one of the most important criteria by which people judge the total quality of the car. Traditionally to investigate the vehicle ride comfort, some well-known classical lumped-mass models are used. In these models such as quarter car model, half car model and full vehicle model, body flexibility has been ignored and sprung mass (vehicle body) assumed to be rigid. This assumption can reduce the model accuracy, specially in the case of long vehicles such as vans, buses and trucks. To impose body flexibility in the ride analysis, recently some numerical FEM-based models have been introduced, but they are complex and non-parametric. In this paper the effects of body flexibility on the vehicle vibration behavior has been studied based on an analytical approach. For this purpose, a new simple and parametric lumped-mass 8 DOF model has been developed. Comparison of the results of natural frequency analysis and forced vibration analysis for this model with the corresponding results of so called “rigid model” or “classic model” is very informative. As the results are shown, body flexibility strongly influenced on the acceleration and displacement responses of the vehicle so that it is necessary to considering this term at the early stages of the vehicle design.

Evaluation of Human Exposure to Vibrations using Quarter Car Model with Semi-Active Suspension

2018 ◽  
Vol 10 (4) ◽  
Author(s):  
D.V.A. Rama Sastry ◽  
K.V. Ramana ◽  
N. Mohan Rao ◽  
M. Phani Kumar ◽  
V.S.S. Rama Chandra Reddy
Keyword(s):  
Human Body ◽  
Ride Comfort ◽  
Mr Damper ◽  
Active Suspension ◽  
Suspension System ◽  
Lumped Mass ◽  
Passive Suspension ◽  
Quarter Car Model ◽  
Car Model ◽  
Quarter Car

Exposure of human body to vehicular vibrations in transit may lead to the human discomfort. Ride comfort is one of the major issues in design of automobiles. Magneto rheological (MR) dampers are emerging as most feasible solution for various applications in controlling vibrations. An MR damper is a semi-active device, which will offer the advantages of both active and passive suspension. In this study, the MR damper based semi-active suspension system for a car is analysed for ride comfort of 7 degrees of freedom model human body lumped mass, considering head, upper torso, lower torso and pelvis, seated over a seat of a quarter car model and is compared with that of similar system using passive damper. A MR damper is fabricated and is filled with MR fluid made of Carbonyl iron powder and Silicone oil added with additive. Modified Bouc-Wen Model developed by Spencer is used to model the behaviour of MR damper. All the parameters of this model are identified using data acquired from experiments conducted to characterise MR damper. Further, using the Spencer model of MR damper, the human body seated over quarter car is simulated by implementing a semi-active suspension system for analysing the resulting displacement and acceleration of the human body. The ride comfort performance of vehicle model with passive suspension system is compared with corresponding semi-active suspension system. The simulation and analysis are carried out using MATLAB/SIMULINK.

scholarly journals ROAD PAVEMENT LONGITUDINAL EVENNESS QUANTIFICATION AS STATIONARY STOCHASTIC PROCESS

Transport ◽  
2019 ◽  
Vol 34 (3) ◽  
pp. 193-203 ◽  
Author(s):  
Bohuš Leitner ◽  
Martin Decký ◽  
Matúš Kováč
Keyword(s):  
Ride Comfort ◽  
Reference Model ◽  
Rolling Resistance ◽  
Geodetic Survey ◽  
Work Place ◽  
Quarter Car Model ◽  
Car Model ◽  
Road Pavement ◽  
Research Activities ◽  
Quarter Car

One of the requirements concerning pavement quality is the evenness of its surface. Pavement unevenness has a random character and has an adverse influence to rolling resistance, tyre–pavement coherence, safety and the driving comfort. Knowledge of “longitudinal unevenness” has been long recognized as an important criteria of road performance, not only for safety by causing vehicle vibrations and affecting ride comfort but also as a major factor in pavement deterioration and working conditions of vehicles. The paper presents two original devices for the measurement of pavement longitudinal unevenness designed as a reaction to results and experiences gathered from a few years’ research activities, measurements and evaluations of road pavement evenness carried out in the authors' work place (University of Žilina – UNIZA). The first equipment has been designed as a single-wheel trailing vehicle and has been constructed on the Double-mass Measuring Set (DMS) principle and it is referred to as UNIZA single-wheel vehicle JP VSDS. The main reason for designing the device were authors’ findings that the reference quarter car model (used for calculation of International Roughness Index – IRI) can provide evaluation, which can be in contradiction with ride safety. This fact is determined by overvaluation of the short wavelengths and undervaluation the longer wavelengths by reference model. The second one is a profiler with very high resolution of surface scanning using mathematical models for unevenness evaluation. The device is referred to as Dynamic Road Scanner (DRS). The reason for designing of this equipment was in the first place insufficient repeatability of transversal unevenness measurements of device used by Slovak Road Administration, but for the purpose of correctness and measurements accuracy verifying were also results of longitudinal unevenness measurements compared. The paper presents results of evaluation by international established dynamic quantifiers of longitudinal unevenness based on measurements performed by these devices on three selected road sections in Slovakia. In the next part of the paper are compared IRI values obtained by mathematical calculations using reference quarter car model “driving” on road section profile measured by geodetic survey with IRI values obtained by conversion of the unevenness degree C (measured by UNIZA single-wheel vehicle JP VSDS) and IRI values measured by profilometer DRS.

scholarly journals Mixed Skyhook and FxLMS Control of a Half-Car Model with Magnetorheological Dampers

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Piotr Krauze ◽  
Jerzy Kasprzyk
Keyword(s):  
Control Strategies ◽  
Mr Damper ◽  
Front Axle ◽  
Vehicle Body ◽  
Magnetorheological Dampers ◽  
The Road ◽  
Quarter Car Model ◽  
Car Model ◽  
Road Roughness ◽  
Suspension Model

The problem of vibration attenuation in a semiactive vehicle suspension is considered. The proposed solution is based on usage of the information about the road roughness coming from the sensor installed on the front axle of the vehicle. It does not need any preview sensor to measure the road roughness as other preview control strategies do. Here, the well-known Skyhook algorithm is used for control of the front magnetorheological (MR) damper. This algorithm is tuned to a quarter-car model of the front part of the vehicle. The rear MR damper is controlled by the FxLMS (Filtered-x LMS) taking advantage of the information about the motion of the front vehicle axle. The goal of this algorithm is to minimize pitch of the vehicle body. The strategy is applied for a four-degree-of-freedom (4-DOF) vehicle model equipped with magnetorheological dampers which were described using the Bouc-Wen model. The suspension model was subjected to the road-induced excitation in the form of a series of bumps within the frequency range 1.0–10 Hz. Different solutions are compared based on the transmissibility function and simulation results show the usefulness of the proposed solution.

H∞ Control of Active Suspension System for a Quarter Car Model

2016 ◽  
Vol 8 (1) ◽  
Author(s):  
N.M. Ghazaly ◽  
A.S Ahmed ◽  
A.S Ali ◽  
G.T Abd El- Jaber
Keyword(s):  
Ride Comfort ◽  
Active Suspension ◽  
Suspension System ◽  
Passive Suspension ◽  
Quarter Car Model ◽  
Suspension Systems ◽  
Car Model ◽  
Active Suspension Systems ◽  
Passive Suspension System ◽  
Quarter Car

In recent years, the use of active control mechanisms in active suspension systems has attracted considerable attention. The main objective of this research is to develop a mathematical model of an active suspension system that is subjected to excitation from different road profiles and control it using H∞ technique for a quarter car model to improve the ride comfort and road handling. Comparison between passive and active suspension systems is performed using step, sinusoidal and random road profiles. The performance of the H∞ controller is compared with the passive suspension system. It is found that the car body acceleration, suspension deflection and tyre deflection using active suspension system with H∞ technique is better than the passive suspension system.

Ride comfort analysis of passenger body biodynamics in active quarter car model using adaptive neuro-fuzzy inference system based super twisting sliding mode control

2019 ◽  
Vol 25 (12) ◽  
pp. 1866-1882 ◽  
Author(s):  
Devdutt Singh
Keyword(s):  
Sliding Mode Control ◽  
Human Body ◽  
Ride Comfort ◽  
Fuzzy Inference ◽  
Sliding Mode ◽  
Inference System ◽  
Quarter Car Model ◽  
Car Model ◽  
Mode Control ◽  
Quarter Car

In this paper, a four degrees of freedom biodynamic human body model is used for ride comfort analysis, which is coupled with a three degrees of freedom quarter car model. The random road profile is generated in a simulation environment using the ISO 8608:2016 standard. In order to suppress the adverse effects of road induced vibrations on the human body, a super-twisting sliding mode control (STSMC) and adaptive neuro-fuzzy inference system (ANFIS) based super-twisting sliding mode control (ASTSMC) strategy is used in the main suspension of the active quarter car model. The ride comfort response of the human body segments is compared for passive and active suspension systems using the ISO 2631-1:1997 standard. Based on the simulation results in time and frequency domain related to acceleration and displacement response for head and neck, upper torso, viscera and lower torso, it is shown that the ride comfort provided by the ASTSMC controller is much improved compared to the STSMC and passive control method. It can be finalized from the present research work that active suspension with the ASTSMC control strategy can successfully reduce the adverse effects of road induced vibrations on human body health and safety.

Analysis of Ride comfort and Road holding of Quarter car model by SIMULINK

2017 ◽  
Vol 4 (2) ◽  
pp. 2425-2430 ◽  
Author(s):  
Trupti P. Phalke ◽  
Anirban C. Mitra
Keyword(s):  
Ride Comfort ◽  
Quarter Car Model ◽  
Car Model ◽  
Quarter Car

In-Plane Rigid Ring-Based Tire Model: Parameter Identification, Sensitivity Analyses, and Effect on Ride Comfort

2014 ◽  
Author(s):  
Bin Li ◽  
Ning Li ◽  
Xiaobo Yang ◽  
James Yang
Keyword(s):  
Ride Comfort ◽  
Contact Forces ◽  
Tire Model ◽  
Spring Stiffness ◽  
Rigid Ring ◽  
Quarter Car Model ◽  
Car Model ◽  
Ring Radius ◽  
Road Load

The tire is the main interface between the vehicle and road, and all maneuvers controlled by a driver to road vehicle are achieved by the interaction force between tire and road. In modern vehicle design, tire modeling plays an important role in effectively assessing vehicle handling, ride comfort, and road load analysis. The long term goal of this research is to develop a three-dimensional robust tire model that can be used for road load durability simulation. This work is the first step to the long term goal. This paper presents a new simplified in-plane tire model based on a traditional rigid ring tire model. The interaction between the tire and road is assumed to be patch contact. Optimization technique is used to obtain all key tire parameters of the tire model by minimizing the vertical and horizontal contact forces between the model simulation results and road test data when a tire passes a road bump. After the parameters are identified, a full factorial design of experiments with three levels for each of 8 parameters (horizontal spring stiffness and damper coefficient, vertical spring stiffness and damper coefficient, rotational spring stiffness and damper coefficient between the rim and ring, ring radius, ring residual spring stiffness) is conducted for parameter sensitivity analysis. The three levels for each parameter except the ring radius are 50% increase, 50% decrease, and nominal values. Sensitivity analysis has shown that several parameters are critical to the peak value of the vertical and horizontal contact forces. A quarter-car model is then used to assess ride comfort of the vehicle suspension system. The quarter-car model with the proposed tire model can more accurately predict the ride comfort subject to random road inputs than the one with point contact tire model.

Optimization of Asymmetric Damper Parameters of an Automotive Suspension for Minimal Camber Angle Variations

2010 ◽  
Author(s):  
Krishna Prasad Balike ◽  
Subhash Rakheja ◽  
Ion Stiharu
Keyword(s):  
Ride Comfort ◽  
Dynamic Responses ◽  
Simulation Studies ◽  
Angle Variation ◽  
Quarter Car Model ◽  
Car Model ◽  
Camber Angle ◽  
Nonlinear Relation ◽  
Automotive Suspension ◽  
Design Guidance

Asymmetric dampers invariably employed in automotive suspensions are known to cause ‘damper jacking’. The influence of the damper jacking on the suspension kinematic responses, particularly variations in the camber angle, are generally ignored while synthesizing a damper. This study presents influences of damper asymmetry on the camber angle variations of a double wishbone type of suspension together with the dynamic responses under measured urban road inputs. Simulation studies employing a kineto-dynamic quarter-car model comprising a bilinear damper revealed increase in the camber angle variations with an increase in the damper asymmetry, while this increment showed nonlinear relation with the suspension deflection. This study further investigates synthesis of an optimal two-stage asymmetric damper to yield a compromise between the conflicting performance measures. A composite performance index comprising the ride comfort and road holding measures with limit constraint on camber angle variation is formulated to seek optimal damper parameters. The results are presented so as to yield design guidance for synthesis of asymmetric dampers.

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