Mathematical Model of a Buckled Spring for Vehicle Active Suspension

1997 ◽  
Author(s):  
Shiping Yao ◽  
Colin Morgan ◽  
Nigel J. Leighton
Keyword(s):  
Dynamic Performance ◽  
Active Suspension ◽  
Effective Rate ◽  
Suspension System ◽  
Leaf Spring ◽  
Practical Application ◽  
Resonance Effects ◽  
Spring Element ◽  
Constant Rate ◽  
Force Displacement

Abstract The basic characteristic of a conventional spring is that of a constant rate, that is a linear force-displacement relationship. If, however, a flat, thin leaf spring is end-loaded past its buckling point it will deform into a curve and the resulting force-displacement relationship can be made virtually flat; that is a very low effective rate is seen, once the buckling force is exceeded. A novel form of automotive active suspension system proposed by Leighton & Pullen (1994) relies upon the “buckled spring” element acting through a variable geometry wishbone assembly to provide wheel to body forces that are controllable by a low power actuator but are virtually independent of wheel to body displacement. The dynamic behavior of the spring element is also significant, since resonance effects may affect the vibration isolating properties of the suspension system and may result in unstable modes of motion. This paper presents a rigorous derivation of the static and dynamic characteristic of the spring element and of the effect of design compromises that are essential for practical application. Comparison of the experimental and simulation results shows that the simulation can be used to predict the static and dynamic performance of the spring.

Performance analysis of MR damper based semi-active suspension system using optimally tuned controllers

2021 ◽  
pp. 095440702110044
Author(s):  
Gurubasavaraju Tharehalli mata ◽  
Vijay Mokenapalli ◽  
Hemanth Krishna
Keyword(s):  
Pid Controller ◽  
Ride Comfort ◽  
Sliding Mode ◽  
Dynamic Performance ◽  
Parametric Method ◽  
Mr Damper ◽  
Active Suspension ◽  
Suspension System ◽  
Sliding Mode Controller ◽  
Road Excitation

This study assesses the dynamic performance of the semi-active quarter car vehicle under random road conditions through a new approach. The monotube MR damper is modelled using non-parametric method based on the dynamic characteristics obtained from the experiments. This model is used as the variable damper in a semi-active suspension. In order to control the vibration caused under random road excitation, an optimal sliding mode controller (SMC) is utilised. Particle swarm optimisation (PSO) is coupled to identify the parameters of the SMC. Three optimal criteria are used for determining the best sliding mode controller parameters which are later used in estimating the ride comfort and road handling of a semi-active suspension system. A comparison between the SMC, Skyhook, Ground hook and PID controller suggests that the optimal parameters with SMC have better controllability than the PID controller. SMC has also provided better controllability than the PID controller at higher road roughness.

A Novel Active Suspension System for Automotive Application

1994 ◽  
Vol 208 (4) ◽  
pp. 243-250 ◽  
Author(s):  
N J Leighton ◽  
J Pullen
Keyword(s):  
Computer Simulation ◽  
Active Suspension ◽  
Input Power ◽  
Suspension System ◽  
Automotive Application ◽  
Test Results ◽  
Active System ◽  
Spring Element

This paper describes a novel type of active suspension based on a buckling spring element installed in an actively controlled variable leverage system. The development of the suspension system through stages of computer simulation, implementation and test is outlined, together with the test results. The suspension system does not fall into any of the established categories of active system but may be seen as fitting into a recently identified category of variably leverage systems. The system is shown to be capable of controlling a vehicle body's motion while providing excellent road input isolation and requiring input power levels of below 150 watts per wheel.

Fuzzy Controller for Semi-Active Automobile Suspension System under Random Profiled Road Input

2014 ◽  
Vol 668-669 ◽  
pp. 474-477
Author(s):  
Qi Hua Ma ◽  
Jing Luo ◽  
Chun Yan Zhang
Keyword(s):  
Ride Comfort ◽  
Fuzzy Controller ◽  
Dynamic Performance ◽  
Active Suspension ◽  
Suspension System ◽  
Vehicle Body ◽  
Control Laws ◽  
Passive Suspension ◽  
External Conditions ◽  
Set Up

The suspension system is one of the most important parts of the automobile. The suspension system has an important influence on the ride comfort and maneuverable stability of the automobile. As structure parameters of traditional passive suspension cannot adaptively change with external conditions, the improvement of dynamic performance is difficult. Tow-DOF and four-DOF suspension of vehicle model is set up in this paper. Under random profiled road input simulated by using Runge-Kutta method, the control laws of fuzzy controller are adjusted by using different weight coefficients and use Matlab software to simulate the performances. Then, the results are compared and the performances are analyzed between passive suspension and semi-active suspension. The simulation results show the semi-active suspension is more effective for decreasing the vibration of vehicle body than the passive suspension, and designed fuzzy controller is effective for controlling the active controller of the semi-active suspension.

The Time-Delay Study on Vehicle Active Control Suspension

2011 ◽  
Vol 383-390 ◽  
pp. 52-58
Author(s):  
Fa Rong Kou
Keyword(s):  
Time Delay ◽  
Fuzzy Controller ◽  
Dynamic Performance ◽  
Critical Time ◽  
Active Suspension ◽  
Suspension System ◽  
Delay Compensation ◽  
The Road ◽  
Key Factor ◽  
Time Delay Compensation

Actuator is a key factor for vehicle active suspension. A new vehicle active suspension is put forward based on the Electro-Hydrostatic Actuator (EHA).For vehicle active suspension system, unavoidable time delay may appear in the controllable course. The critical time-delay of EHA active suspension is calculated in this paper and time-delay influence on the dynamic performance of vehicle active suspension is analyzed. A time-delay compensation strategy for EHA active suspension is proposed to reduce time delay. A self-adapting fuzzy controller is designed and applied to active suspension system with EHA. Physical prototype and experimental rig for EHA active suspension are built. Then time-delay tests of suspension prototype are carried out on the developed test rig. Test results show that the sprung mass acceleration of the active suspension with time-delay compensation significantly declines by 12.4% under the road input of 1.2Hz and by 13.6% under the road input of 1.6Hz.

Design and experimental research on electromagnetic active suspension with energy-saving perspective

2019 ◽  
Vol 234 (2) ◽  
pp. 487-500
Author(s):  
Jiajia Wang ◽  
Long Chen ◽  
Ruochen Wang ◽  
Xiangpeng Meng ◽  
Dehua Shi
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Dynamic Performance ◽  
Active Suspension ◽  
Linear Motor ◽  
Suspension System ◽  
System Structure ◽  
Theoretical Research ◽  
Hydraulic Damper ◽  
Driving Conditions

A hydraulic damper can improve system reliability when it is introduced to an electromagnetic active suspension equipped with a linear motor. In this study, the effect of damping value on the energy consumption of an electromagnetic active suspension system is investigated with an energy-saving perspective. A kinetic model of electromagnetic active suspension is established, and a controller is designed on the basis of a linear quadratic regulator. Three different levels of roads are then chosen as driving conditions, and the corresponding control targets are set. The effects of damping value on energy consumption and dynamic performance of electromagnetic active suspension under different driving conditions are determined. Results show that damping value does not affect dynamic performance at the same weighting factor or the same driving condition in a time domain. Compared with that of an electromagnetic active suspension without a damper in parallel, the energy consumption of the electromagnetic active suspension system initially decreases and subsequently increases as the damping value increases. Therefore, appropriate damping values can significantly reduce energy consumption. In a frequency domain, appropriate damping values can improve driving safety but can slightly deteriorate ride comfort. An integrated electromagnetic actuator is also designed by integrating the linear motor with the hydraulic damper to construct a practical system structure. These parameters are optimized to improve air-gap magnetic field strength. Thus, the initial design of the structure and dimension of the electromagnetic active suspension system is completed. Finally, the prototype is produced and a 1/4 bench test is also conducted to verify the correctness of theoretical research.

Energy-saving control strategy design and structure realization for electromagnetic active suspension

2018 ◽  
Vol 233 (9) ◽  
pp. 3060-3075 ◽  
Author(s):  
Renkai Ding ◽  
Ruochen Wang ◽  
Xiangpeng Meng
Keyword(s):  
Energy Saving ◽  
Active Control ◽  
Control Strategy ◽  
Dynamic Performance ◽  
Active Suspension ◽  
Linear Motor ◽  
Suspension System ◽  
Passive Damping ◽  
Energy Regeneration ◽  
Energy Saving Control

An electromagnetic active suspension equipped with a linear motor can remarkably improve the dynamic performance of a vehicle in terms of ride comfort and handling stability. However, electromagnetic active suspensions consume a considerable amount of external energy. Therefore, an energy-saving control strategy and its corresponding realization structure are designed to reconcile the contradiction between the dynamic performance and energy consumption. The energy conservation feasibility of an electromagnetic active suspension system is investigated in this study. Subsequently, the conventional skyhook control strategy is used as a reference; a passive damping is introduced to improve the defects of the system for an active control. It can also ensure the basic dynamic performance during energy regeneration. The energy-saving control strategy is placed beside the switch between the active control and energy regeneration. The vehicle simulation manifests that the energy-saving control strategy can effectively inhibit body movement, including vibration, roll, and pitch, while exhibiting a good road holding. A single linear motor used for the suspension system deteriorates the dynamic performance during energy regeneration and cannot guarantee the system reliability because of its low passive damping. Thus, a new integrated electromagnetic actuator prototype is developed, and the bench test shows that the prototype can satisfy the control requirements of the energy-saving control strategy.

scholarly journals DESIGN AND ANALYSIS OF DYNAMIC PERFORMANCE OF A VEHICLE ACTIVE SUSPENSION SYSTEM

2011 ◽  
Vol 11 (ASAT CONFERENCE) ◽  
pp. 1-17
Author(s):  
Z. IBRAHIM ◽  
I. ELSHERIF ◽  
M. RABIE ◽  
S. HEGAZY
Keyword(s):  
Dynamic Performance ◽  
Active Suspension ◽  
Suspension System

scholarly journals The Active Fractional Order Control for Maglev Suspension System

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Peichang Yu ◽  
Jie Li ◽  
Jinhui Li
Keyword(s):  
Fractional Order ◽  
Dynamic Performance ◽  
Suspension System ◽  
Practical Application ◽  
Robust Performance ◽  
Sensors And Actuators ◽  
Maglev Train ◽  
Fractional Order Controller ◽  
The Mathematical Model ◽  
Core Part

Maglev suspension system is the core part of maglev train. In the practical application, the load uncertainties, inherent nonlinearity, and misalignment between sensors and actuators are the main issues that should be solved carefully. In order to design a suitable controller, the attention is paid to the fractional order controller. Firstly, the mathematical model of a single electromagnetic suspension unit is derived. Then, considering the limitation of the traditionalPDcontroller adaptation, the fractional order controller is developed to obtain more excellent suspension specifications and robust performance. In reality, the nonlinearity affects the structure and the precision of the model after linearization, which will degrade the dynamic performance. So, a fractional order controller is addressed to eliminate the disturbance by adjusting the parameters which are added by the fractional order controller. Furthermore, the controller based onLQRis employed to compare with the fractional order controller. Finally, the performance of them is discussed by simulation. The results illustrated the validity of the fractional order controller.

Sign in / Sign up

Export Citation Format

Share Document