Research on Performances of a Displacement Controllable Active Suspension

2018 ◽  
Author(s):  
Zhen Zhao ◽  
Lin Xu ◽  
Beibei Liu ◽  
Mohamed A. A. Abdelkareem ◽  
Junyi Zou ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Shock Absorber ◽  
Active Suspension ◽  
The Body ◽  
Magnetorheological Damper ◽  
Vehicle Body ◽  
Characteristic Functions ◽  
Dynamic Performances ◽  
Electric Cylinder ◽  
Driving Stability

The suspension is one of the most important systems in a vehicle, which can decrease the vehicle body vibration and maintain good ride performance and driving stability. As for strikingly rugged roads like off-road conditions, the traditional active suspension can hardly balance the contradiction between the wheel adhesion and the vertical accelerated speed of the body. To accelerate to a higher speed while ensuring the ride performance at the same time, high-quality suspension system must be created and applied. As we all know, the active suspension can improve the driving stability and ride performance dramatically. In order to achieve the controllable adjustment of shock absorber damping and vehicle height, and realize the optimization of vehicle suspension performance, a new kind of active suspension which includes magnetorheological damper and servo electric cylinder is proposed. Then, the mathematical model of the proposed active suspension based on “Servo Electric Cylinder-Spring-Magnetorheological damper” is established after being simplified. Finally, the dynamic performances of the passive and active suspension in different modes are simulated by MATLAB based on its mathematical model and dynamic characteristic functions. The results indicate that the proposed active suspension, compared with the passive, can achieve the controlled adjustment of shock absorber damping and vehicle height, and ensure the ride performance.

Impact of Electric Vehicle Lateral Dynamics on the Battery Pack

2014 ◽  
Vol 590 ◽  
pp. 451-457
Author(s):  
Sen Nan Song ◽  
Fa Chao Jiang ◽  
Hong Shi
Keyword(s):  
Mathematical Model ◽  
Angular Acceleration ◽  
Simulation Software ◽  
The Body ◽  
Battery Pack ◽  
Vehicle Body ◽  
Rolling Motion ◽  
Rolling Angle ◽  
On The Road ◽  
The Mathematical Model

The present work is concerned with the rolling motion of the battery pack when EV travelling on the road. First McPherson suspension system was regarded as the research object with detailed analysis of its structural features and motion characteristics. Establish the mathematical model which could apply to calculating the rolling motion of the vehicle body. Through MATLAB/Simulink simulation software, we could calculate the rolling angle on passive suspension. On this basis, assume that the battery pack mounted on the vehicle body and make it passive connection and PID connection. When the body rolls, the battery pack will produce a certain angle then. Next establish the mathematical model to summarize the relationship between the two variables. Then we set the parameters and calculate the roll angle of battery pack in both cases for comparison. Simulation results show that road irregularities will make battery rotate an angle and PID controller can effectively reduce the angle, especially angular acceleration. This paper put forward a new idea that battery is connected with body by active control on EV, and proves the superiority in reducing the rolling angle.

scholarly journals Experimental Researches on the Dynamic Behavior of the Magnetorheological Damper

2020 ◽  
Author(s):  
Alexandru Dobre
Keyword(s):  
Dynamic Behavior ◽  
Shock Absorber ◽  
Active Suspension ◽  
Suspension System ◽  
Magnetorheological Damper ◽  
Passenger Cars ◽  
Damping Force ◽  
The Road ◽  
Shock Absorbers ◽  
Road Profile

In the context of improving the comfort and dynamics of the vehicle, the suspension system has been continuously developed and improved, especially using magnetorheological (MR) shock absorbers. The development of this technology which is relatively new has not been easy. Thus, the first widespread commercial use of MR fluid in a semi-active suspension system was implemented in passenger cars. The magnetorheological shock absorber can combine the comfort with the dynamic driving, because it allows the damping characteristic to be adapted to the road profile. The main objective of the paper is to analyze the dynamic behavior of the magnetorheological shock absorber in the semi-active suspension. In this sense, the author carried out a set of experimental measurements with a damping test bench, specially built and equipped with modern equipment. The results obtained from the experimental determinations show a significantly improved comfort when using a magnetorheological shock absorber, compared to a classic one, by the fact that the magnetorheological shock absorber allows to modify the damping coefficient according to the road conditions, thus maintaining the permanent contact between the tire and the road due to increased damping force.

Landing of descent objects with a closed spherical pneumatic shock absorber

2003 ◽  
Vol 3 ◽  
pp. 60-71
Author(s):  
S.S. Komarov ◽  
N.I. Miskaktin ◽  
N.Yu. Tsvileneva
Keyword(s):  
Mathematical Model ◽  
Boundary Conditions ◽  
Nonlinear Boundary ◽  
Shock Absorber ◽  
Nonlinear Boundary Conditions ◽  
The Body ◽  
Power Structures ◽  
Movement System ◽  
Pneumatic Shock

The landing of the landing object with a closed pneumatic shock absorber is considered. A mathematical model of planting the ”object–pneumatic shock absorber“ system is being constructed. Nonlinear boundary conditions in the sealing of the pneumatic shock absorber on the body of the landing object and in the area of interaction with the screen in the power structures in the ”object–pneumatic shock absorber“ movement system.

Wheelbase preview control of an active suspension with a disturbance-decoupled observer to improve vehicle ride comfort

2019 ◽  
Vol 234 (6) ◽  
pp. 1725-1745
Author(s):  
Baek-soon Kwon ◽  
Daejun Kang ◽  
Kyongsu Yi
Keyword(s):  
Simulation Study ◽  
Control Algorithm ◽  
Ride Comfort ◽  
Active Suspension ◽  
The Body ◽  
Vehicle Body ◽  
Preview Control ◽  
The Road ◽  
Road Disturbance ◽  
Suspension Control

This article deals with the design of a partial preview active suspension control algorithm for the improvement of vehicle ride comfort. Generally, while preview-controlled active suspension systems have even greater potential than feedback-controlled systems, their main challenge is obtaining preview information of the road profile ahead. A critical drawback of the “look-ahead” sensors is an increased risk of incorrect detection influenced by water, snow, and other soft obstacles on the road. In this work, a feasible wheelbase preview suspension control algorithm without information about the road elevation has been developed based on a novel 3-degree-of-freedom full-car dynamic model which incorporates only the vehicle body dynamics. The main advantage of the employed vehicle model is that the system disturbance input vector consists of vertical wheel accelerations that can be measured easily. The measured acceleration information of the front wheels is used for predictive control of the rear suspension to stabilize the body motion. The suspension state estimator has also been designed to completely remove the effect of unknown road disturbance on the state estimation error. The estimation performance of an observer is verified via a simulation study and field tests. The performance of the proposed suspension controller is evaluated on a frequency domain and time domain via a simulation study. It is shown that the vehicle ride comfort can be improved more by the proposed wheelbase preview control approach than by the feedback approach.

Modeling and Simulation of a Displacement Controllable Active Suspension System

2018 ◽  
Author(s):  
Beibei Liu ◽  
Lin Xu ◽  
Zhen Zhao ◽  
Mohamed A. A. Abdelkareem ◽  
Junyi Zou ◽  
...  
Keyword(s):  
Attitude Control ◽  
High Speed ◽  
Ride Comfort ◽  
Simulation Analysis ◽  
Body Position ◽  
Active Suspension ◽  
Suspension System ◽  
The Body ◽  
Vehicle Body ◽  
Dynamic State

Active suspension can adapt itself to the rigidity and the damping characteristics based on the vehicle dynamic state and the road condition, making the suspension in the best state of shock absorbing, which can increase the handling stability, the ride comfort and the passing ability of vehicles. As for strikingly rugged roads like off-road conditions, the traditional active suspension can hardly balance the contradiction between the wheel adhesion and the vertical accelerated speed of the body. In this paper, an active suspension in which the position of the vehicle body can be adjusted is proposed. In the proposed suspension, a series of electric cylinders are installed, which can actively adjust the position between the vehicle body and the suspension in order to achieve the purpose of controlling the relative body-wheels position. In this manner, AMESim is used to set up three suspension designs which include suspension supporter adaptation equipment with different locations in the system. Through simulation analysis, the paper has explored the feasibility of the vehicle attitude control of the three suspension designs under off-road conditions. The results proved that the active suspension system with adjustable body position can restrain the body roll or pitch efficiently in which this technology can be applied to the body attitude control when ORVs are at high speed.

Neural Network Control for a Semi-Active Vehicle Suspension with a Magnetorheological Damper

2004 ◽  
Vol 10 (3) ◽  
pp. 461-471 ◽  
Author(s):  
D. L. Guo ◽  
H. Y. Hu ◽  
J. Q. Yi
Keyword(s):  
Neural Network ◽  
Low Frequency ◽  
Active Suspension ◽  
Network Control ◽  
Magnetorheological Damper ◽  
Vehicle Body ◽  
Vehicle Suspension ◽  
Neural Network Control ◽  
Magnetorheological Dampers ◽  
Back Propagation Algorithm

Semi-active vehicle suspension with magnetorheological dampers is a promising technology for improving the ride comfort of a ground vehicle. However, the magnetorheological damper always exhibits nonlinear hysteresis between its output force and relative velocity, and additional nonlinear stiffness owing to the state transition from liquid to semi-solid or solid, so that the semi-active suspension with magnetorheological dampers features nonlinearity by nature. To control such nonlinear dynamic systems subject to random road roughness, in this paper we present a neural network control, which includes an error back propagation algorithm with quadratic momentum of the multilayer forward neural networks. Both the low frequency of road-induced vibration of the vehicle body and the fast response of the magnetorheological damper enable the neural network control to work effectively on-line. The numerical simulations and an experiment for a quarter-car model indicate that the semi-active suspension with a magnetorheological damper and neural network control is superior to the passive suspensions in a range of low frequency.

scholarly journals A review of the vehicle suspension system

2020 ◽  
Vol 4 (2) ◽  
pp. 109-114
Author(s):  
Iyasu T. Jiregna ◽  
Goftila Sirata
Keyword(s):  
Active Suspension ◽  
Suspension System ◽  
The Body ◽  
Vehicle Body ◽  
Vehicle Suspension ◽  
The Road ◽  
Suspension Systems ◽  
Active Suspension Systems ◽  
Different Types ◽  
Proper Design

The driving comfort of the vehicle is primarily determined by the design of the suspension system, which transmits the force between the vehicle and the ground. There are different types of vehicle suspension systems, including active suspension systems that provide significant benefits for ride comfort while driving. However, the existing active suspension systems have limited functions such as power, and also complex structure. To overcome the problem, the proper design of the active suspension system by considering its present limitations is essential. A well-designed active suspension system controls the load on the wheels under the resonance of the body structure and ensures driving comfort. It reduces the vibrational energy of the vehicle body caused by the excitation of the road while keeping the stability of the vehicle within an acceptable limit. For a proper design of the active suspension system, the road surface, the seat suspension, and the wheel load are the most important elements to consider. In this study, different types of vehicle suspension systems with their limitations have been thoroughly investigated. Many aspects of control and some of the essential practical considerations are also explored.

scholarly journals Innovative concepts for the usage of veneer-based hybrid materials in vehicle structures

2021 ◽  
pp. 146442072199839
Author(s):  
DB Heyner ◽  
G Piazza ◽  
E Beeh ◽  
G Seidel ◽  
HE Friedrich ◽  
...  
Keyword(s):  
Steel Strip ◽  
High Energy ◽  
The Body ◽  
Vehicle Body ◽  
Material System ◽  
Laminated Veneer Lumber ◽  
Hybrid Beam ◽  
Bending Load ◽  
The Impact ◽  
Very High

A promising approach for the development of sustainable and resource-saving alternatives to conventional material solutions in vehicle structures is the use of renewable raw materials. One group of materials that has particular potential for this application is wood. The specific material properties of wood in the longitudinal fiber direction are comparable to typical construction materials such as steel or aluminum. Due to its comparatively low density, there is a very high lightweight construction potential especially for bending load cases. Structural components of the vehicle body are exposed to very high mechanical loads in the case of crash impact. Depending on the component under consideration, energy has to be absorbed and the structural integrity of the body has to be ensured in order to protect the occupants. The use of natural materials such as wood poses particular challenges for such applications. The material characteristics of wood are dispersed, and depend on environmental factors such as humidity. The aim of the following considerations was to develop a material system to ensure the functional reliability of the component. The test boundary conditions for validation also play a key role in this context. The potential of wood–steel hybrid design based on laminated veneer lumber and steel was investigated for use in a component subjected to crash loads such as the door impact beam. The chosen solution involves a separation of functions. A laminated veneer lumber-based beam was hybridized with a steel strip on the tension side. The steel strip was designed to compensate the comparatively low elongation at fracture of the wood and to ensure the integrity of the beam. The wooden component was designed for high energy absorption due to delamination and controlled failure during the impact, while maintaining the surface moment of inertia, i.e. the bending stiffness of the entire component. This approach was chosen to ensure the functional safety of the component, avoid sudden component failure and utilize the high potential of both materials. The tests carried out provided initial functional proof of the chosen solution. The hybridization achieved significantly higher deformations without sudden failure of the beam. In addition, bending capabilities were increased significantly compared to a beam without hybridization. In comparison with a state-of-the-art steel beam, the hybrid beam was not able to achieve the maximum deformation and the target weight of the hybrid beam. Further optimization of the hybrid beam is therefore necessary.

scholarly journals Combination of an Improved FRF-Based Substructure Synthesis and Power Flow Method with Application to Vehicle Axle Noise Analysis

2008 ◽  
Vol 15 (1) ◽  
pp. 51-60 ◽  
Author(s):  
C.Q. Liu
Keyword(s):  
Power Flow ◽  
Noise Analysis ◽  
Flow Analysis ◽  
Synthesis Method ◽  
The Body ◽  
Vehicle Body ◽  
Total System ◽  
Simple Formulation ◽  
Substructure Synthesis ◽  
Fea Model

In this paper, an improved FRF-based substructure synthesis method combined with power flow analysis is presented and is used for performing a vehicle axle noise analysis. The major transfer paths of axle noise transmitted from chassis to vehicle body are identified and ranked based on power flows transmitted through bushings between the chassis and body. To calculate the power flows, it is necessary to know the reaction forces and the vibrations at the bushing locations on the body side. To this end, the body is represented in terms of experimentally derived frequency response functions (FRF's) at the bushing locations, and the FRF's are coupled with the FEA model of the chassis for performing a total system dynamic analysis. This paper also describes how the FRF's of the vehicle body and the frequency dependent stiffness data of the bushings can be combined together with a simple formulation to better represent the dynamic characteristics of a full vehicle. A classical example is used to illustrates the concept of the method, and the method is then applied to a vehicle axle noise analysis with detailed procedure. The theoretical predictions are compared with experimentally measured results. Good correlation has been obtained.

The physical basis of mollusk shell chiral coiling

2021 ◽  
Vol 118 (48) ◽  
pp. e2109210118
Author(s):  
Régis Chirat ◽  
Alain Goriely ◽  
Derek E. Moulton
Keyword(s):  
Mathematical Model ◽  
The Body ◽  
Symmetric Body ◽  
Model Organisms ◽  
Physical Interaction ◽  
Mechanical Forces ◽  
Hard Shell ◽  
Left Right Asymmetry ◽  
Development And Evolution ◽  
Mollusk Shell

Snails are model organisms for studying the genetic, molecular, and developmental bases of left–right asymmetry in Bilateria. However, the development of their typical helicospiral shell, present for the last 540 million years in environments as different as the abyss or our gardens, remains poorly understood. Conversely, ammonites typically have a bilaterally symmetric, planispiraly coiled shell, with only 1% of 3,000 genera displaying either a helicospiral or a meandering asymmetric shell. A comparative analysis suggests that the development of chiral shells in these mollusks is different and that, unlike snails, ammonites with asymmetric shells probably had a bilaterally symmetric body diagnostic of cephalopods. We propose a mathematical model for the growth of shells, taking into account the physical interaction during development between the soft mollusk body and its hard shell. Our model shows that a growth mismatch between the secreted shell tube and a bilaterally symmetric body in ammonites can generate mechanical forces that are balanced by a twist of the body, breaking shell symmetry. In gastropods, where a twist is intrinsic to the body, the same model predicts that helicospiral shells are the most likely shell forms. Our model explains a large diversity of forms and shows that, although molluscan shells are incrementally secreted at their opening, the path followed by the shell edge and the resulting form are partly governed by the mechanics of the body inside the shell, a perspective that explains many aspects of their development and evolution.

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