Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Research on Skyhook Control Strategy of Multi-grade Adjustable Damper in Semi-active Air Suspension

- , 2016,
Abstract: 以某重卡汽车阻尼多级可调的电子控制空气悬架系统为研究对象,基于Matlab/Simulink模块分别建立1/4车辆悬架系统模型、理想天棚和实际天棚控制模型,给出阻尼可调的天棚控制器设计方法。该方法分析车身加速度az、悬架动挠度fd和轮胎动载荷tl随阻尼系数的变化规律,对该车辆悬架系统的平顺性(az,fd)和道路友好性(tl)目标进行加权优化处理,得到不同控制策略下使悬架获得最优综合性能的悬架阻尼系数。仿真结果表明:采用优化后的天棚阻尼控制器能够有效改善车辆平顺性和道路友好性。
A quarter heavy truck dynamic model assembled with the electronically controlled air suspension with stepped adjustable damping is studied, and the ideal and actual controller models of the air suspension are presented based on Matlab/Simulink software, then a method of designing skyhook controller is proposed. In this method, variation laws of the body acceleration denoted as az, the suspension dynamic deflection denoted as fd and the tire dynamic load denoted as tl due to the transfer of suspension damping are analyzed. Moreover, ride comfort (az,fd) and road friendliness (tl) indexes of this suspension control model are weighted to create a new comprehensive index, according to which the best damping coefficient under different control strategies can be obtained. Finally, the simulation results indicate that the ride comfort and road friendliness of the heavy truck can be obviously and efficiently improved by using the optimized skyhook damping controller
Automotive Ride Comfort Control Using MR Fluid Damper  [PDF]
Mahmoud El-Kafafy, Samir M. El-Demerdash, Al-Adl Mohamed Rabeih
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.44024
Abstract: In this paper, the performance of automotive ride comfort using Bouc-Wen type magneto-rheological (MR) fluid damper is studied using a two degree of freedom quarter car model. The sliding mode control is used to force the MR damper to follow the dynamics of ideal sky-hock model. The model is tested on two excitations, the first is a road hump with severe peak amplitude and the second is a statistical random road. The results are generated and presented in time and frequency domains using Matlab/Simulink software. Comparison with the fully active, ideal semi-active and conventional passive suspension systems are given as a root mean square values. Simulation results, for the designed controller, show that with the controllable MR damper has a significant improvement for the vehicle road holding then its lateral stability as well as road damage in comparison with passive, fully active and ideal semi-active suspension systems.
Characteristics of Ride Comfort and Torsion Elimination of Four-Corner Interconnected Air Suspension System

江洪, 钱宽, 朱超, 孙禹州
, QIAN Kuan, ZHU Chao, SUN Yuzhou

- , 2015,
Abstract: 摘要: 为提高车辆在不平路面上的行驶平顺性,减小车身所受扭转载荷,提出了一种四角互联空气悬架系统.基于工程热力学和车辆动力学理论,构建了带四角互联空气悬架的整车动力学模型.通过搭建试验台架,验证了所建模型的准确性,并在Matlab/Simulink中进行了仿真分析.研究结果表明:当车辆以20 km/h的速度行驶在对扭路面时,与传统空气悬架相比,四角互联空气悬架可使车身加速度、侧倾角和车轮动载荷分别改善22.5%,24.2%和16.3%, 并消除27.8%的车身扭转载荷,但悬架动行程增大20.6%;连接管路内径在0~10 mm范围增大,互联效果越显著,当车速在10~60 km/h范围时,四角互联空气悬架能有效提升车辆隔振性能,且车速在40 km/h以下消扭效果更加明显.
Abstract: In order to improve the ride comfort and decrease the vehicle body torsion load on uneven roads, a four-corner interconnected air suspension system was proposed. Based on the engineering thermodynamics and the vehicle dynamics theory, a vehicle dynamic model equipped with the four-corner interconnected air suspension was established. Then, the model accuracy was validated by a bench test, and the full vehicle model was simulated under the Matlab/Simulink environment. The results show that when a vehicle equipped with the four interconnected air suspension runs at a low speed on a twisting road, compared to that equipped with the traditional air suspension, the vehicle body acceleration, roll angle and wheel load reduce 22.5%, 24.2% and 16.3%, respectively; the vehicle body torsion load decreases 27.8%; but the suspension dynamic stroke increases 20.6%. Moreover, the interconnection brings about more benefits as the pipe diameter increases from 0 to 10 mm. The four-corner interconnected air suspension can effectively improve the ride comfort when the vehicle speed is in the range of 10-60 km/h, and the torsion elimination characteristics will be more obvious when the speed is less than 40 km/h
Optimization of Damper Top Mount Characteristics to Improve Vehicle Ride Comfort and Harshness  [PDF]
Mina M. S. Kaldas,Kemal ?al??kan,Roman Henze,Ferit Kü?ükay
Shock and Vibration , 2014, DOI: 10.1155/2014/248129
Abstract: A novel optimization technique for optimizing the damper top mount characteristics to improve vehicle ride comfort and harshness is developed. The proposed optimization technique employs a new combined objective function based on ride comfort, harshness, and impact harshness evaluation. A detailed and accurate damper top mount mathematical model is implemented inside a validated quarter vehicle model to provide a realistic simulation environment for the optimization study. The ride comfort and harshness of the quarter vehicle are evaluated by analyzing the body acceleration in different frequency ranges. In addition, the top mount deformation is considered as a penalty factor for the system performance. The influence of the ride comfort and harshness weighting parameters of the proposed objective function on the optimal damper top mount characteristics is studied. The dynamic stiffness of the damper top mount is used to describe the optimum damper top mount characteristics for different optimization case studies. The proposed optimization routine is able to find the optimum characteristics of the damper top mount which improve the ride comfort and the harshness performances together. 1. Introduction Damper top mounts are used in the vehicles not only to provide ideal Noise-Vibration-Harshness (NVH) performance but also to improve ride comfort, driving safety, and handling. The ride comfort and harshness can be considered as the vibration response of the vehicle body at different frequency ranges. Vehicle ride comfort can be evaluated by using vertical acceleration of the body up to 20?Hz while the harshness can be considered as the body vertical acceleration in the frequency range over 20?Hz until 100?Hz [1]. Another type of the vehicle harshness is the impact harshness (IH) which also affects the subjective impression of ride comfort. This type of harshness involves the vibration response of the vehicle which is referred to as IH events [2–5]. The driver and the passengers are always in contact with different parts of the vehicle chassis during the operation of the vehicle. Therefore, it is expected that reducing the acceleration response of the vehicle body will improve ride comfort and harshness. Some previous studies have shown that the ride comfort and harshness performance of the vehicle can be improved by optimizing the characteristics of the suspension system components [5–13]. A numerical procedure for finding the optimum values of the vehicle suspension system parameters has been studied by Pintado and Benitez [6]. The vehicle is modeled as a
A Study on Half-car Active Suspension Control by Combining EKF State Observation and Sliding Mode Algorithm

- , 2017,
Abstract: 针对主动悬架控制可能面临的平顺性、悬架动挠度及车轮动载性能冲突,以及考虑参数不确定与外界干扰带来的鲁棒性问题,论文基于非线性滤波方法设计了滑模控制器以综合改善悬架性能;根据控制算法所需实时而准确的车辆状态信息需求,采用扩展卡尔曼滤波方法设计了状态观测器。分别进行随机路面激励、正弦路面激励和凸块路面激励仿真分析,结果显示所设计控制器具有良好的路面适应性,在不牺牲悬架动挠度的情况下,可以有效改善车辆平顺性及轮胎抓地力,有利于综合提升车辆的乘坐舒适性和操纵稳定性。
Due to the fact that there may be trade-offs among ride comfort, suspension deflection and tire deformation for the active suspension system, and considering the robustness of control system with parameter uncertainties and external disturbances, an active suspension controller based on nonlinear filtering method and the sliding mode variable structure control method was designed in order to comprehensively improve the suspension system performance. According to the previously established control algorithm, implementation of the control system requires real-time access to several key states, a state observer was proposed using the extended Kalman filter method. Subsequently, simulation schemes including random road excitation, sinusoidal road excitation and bump road excitation are carried out to validate the effectiveness of the entire control system. The results of the simulations show that, the proposed control system has good road adaptability, and can effectively improve ride comfort and road holding performance without sacrificing suspension deflection. Therefore, the proposed control system is beneficial to improve the ride quality and handling stability of vehicle
Design and Analysis for Sliding Mode-following Controller of Semi-active Suspension System

- , 2017,
Abstract: 为提高车辆行驶平顺性并减小轮胎对路面的动载荷,建立二自由度半主动悬架动力学模型,以理想天棚阻尼控制系统作为参考模型,在实际被控悬架与参考模型系统之间建立误差动力学系统,采用极点配置法设计滑模面。基于Lyapunov理论推导出被控悬架系统渐进稳定条件,并用指数趋近律消减系统抖振,使实际被控系统能够达到理想天棚模型的控制效果并产生渐进稳定的滑模运动。最后,建立基于理想天棚模型的半主动悬架滑模变结构控制仿真模型,并进行仿真验证。结果表明:滑模控制可以很好达到参考模型的控制效果,具有良好的适应性和鲁棒性。
In order to improve the vehicle ride comfort and reduce the tire dynamic load, the 2-DOF mathematical reference model of semi-active suspension system with ideal sky-hook damping is established, and then the error dynamic system is built between the actual controlled system and the reference model system. The sliding mode surface is designed with pole assignment method. Moreover, the asymptotic stability condition of suspension system is derived based on the Lyapunov theory, and the system chattering is reduced with the index control law, which makes the actual controlled system can achieve the control effect of the ideal reference model and produce the asymptotically stable sliding motion. Finally, the sliding mode variable structure control model is built based on the ideal sky-hook damping model of the semi-active suspension. Numerical simulation verification is conducted and results indicate that the sliding mode control has a good control effect of the reference model system with good adaptability and robustness
Research on Ride Comfort Model of Wheel Motor Driving Vehicle Based on Matlab/Simulink  [PDF]
Wenwen Xiao, Feihu Xuan, Huanghuang Zhang
Engineering (ENG) , 2017, DOI: 10.4236/eng.2017.911057
Abstract: Simulink is a visual simulation tool in MATLAB;?through Simulink software,?to establish a model can reduce the amount of programming workload,?and?improve the efficiency of the establishment of automotive models.The ride comfort of the vehicle is a measure of the most basic indicators of a car performance.By establishing a ride comfort model in Matlab/Simulink, the wheel motor electric vehicle mainly affects the smoothness of the car mainly in the following aspects:?pavement, tire, suspension, motor and so on.Through the establishment of the above model,we?can effectively study the wheel motor drive electric vehicle ride comfort research.
Railway Carriage Model to Study the Influence of Vertical Secondary Stiffness on Ride Comfort of Railway Carbody Running on Curved Tracks
Karim H.Ali Abood,Rasheed Ahmid Khan
Modern Applied Science , 2011, DOI: 10.5539/mas.v5n2p11
Abstract: A mathematical model of a railway carriage running on curved tracks is constructed by deriving the equations of motion concerning the model in which single-point and two-point wheel-rail contact is considered. The presented railway carriage model comprises of front and rear simple conventional bogies with two leading and trailing wheelets attached to each bogie. The railway carriage is modeled by 31 degrees of freedom which govern vertical displacement, lateral displacement, roll angle and yaw angle dynamic response of wheelset whereas vertical displacement, lateral displacement, roll angle, pitch angle and yaw angle dynamic response of carbody and each of the two bogies. Linear stiffness and damping parameters of longitudinal, lateral and vertical primary and secondary suspensions are provided to the railway carriage model. Combination of linear Kalker's theory and nonlinear Heuristic model is adopted to calculate the creep forces in which introduced at wheel and rail contact patch area. Computer aided-simulation is constructed to solve the governing differential equations of the mathematical model using Runge-Kutta fourth order method. Principle of limit cycle and phase plane approach is applied to realize the stability and evaluate the concerning critical hunting velocity at which railway carriage starts to hunt. The numerical simulation model is used to study the influence of vertical secondary suspension spring stiffness on the ride passenger comfort of railway carbody running with speeds under and at critical hunting velocity. High magnitudes of vertical secondary spring stiffness suspension introduce undesirable roll and yaw dynamic response in which affect ride passenger comfort at critical hunting velocity. Low critical hunting velocity with railway carriage running on curved tracks can be represented.
Parametric analysis of rail vehicle parameters influencing ride behavior
RC Sharma
International Journal of Engineering, Science and Technology , 2011,
Abstract: This paper presents the influence of rail vehicle parameters on vertical and lateral ride behavior. The analysis considers coupled vertical-lateral 37 degrees of freedom mathematical model of an Indian Railway General Sleeper ICF coach formulated using Largangian dynamics. Both vertical and lateral irregularities of the railway track, considered as random function of time are incorporated in analysis. The ride analysis of the mathematical model suggests that discomfort frequency range lies from 4 to 10.5 Hz and improvements in the design of rail vehicle coach are required for better ride comfort. It is seen from parametric analysis that car body mass, secondary suspension vertical damping, primary suspension vertical damping and wheel base are the most sensitive parameters influencing vertical ride. While lateral ride is significantly influenced by car body mass, roll & yaw mass moment of inertia and secondary suspension lateral stiffness.
M.P. Nagarkar,G.J Vikhe,K.R. Borole,V.M. Nandedkar
International Journal of Automotive and Mechanical Engineering , 2011,
Abstract: The automobile is composed of many systems. One of these is the suspension system. The main functions of the automotive suspension system are to provide vehicle support, stability and directional control during handling manoeuvres and to provide effective isolation from road disturbances. The suspension system has to balance the tradeoff between ride comfort and handling performance. This paper analyses the passive suspension system and active suspension system using a Linear Quadratic Regulator (LQR) controller. A linear quarter-car model is used for the analysis and simulation. The performance of the LQR controller is compared with the passive suspension system. The simulation results show that the LQR controller improves vehicle ride comfort.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.