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Sliding Mode Controlled Half Car Suspension System with Magnetorheological Damper

  • Technical Paper
  • 2020-01-1540
To be published on 2020-06-03 by SAE International in United States
Attenuation of vibrations caused by the road undulance conditions are tedious and very much related to human health and vehicle handling problems. One of the promised approaches to solving these problems in a vehicle suspension system is the use of effective controllers. In this paper, the sliding mode controller (SMC) is designed and used to control the magnetorheological (MR) damper. The performance of the proposed controller is verified by incorporating the controller in a half car vehicle suspension model. In a suspension damper design, Modified Bouc-Wen model is used to characterize the hysteretic behaviour of MR damper parameters. The voltage control algorithm is used to convert the desired force into the varied voltage input to the MR damper. The fail-proof advantage of MR damper is analysed by comparing the results of uncontrolled MR suspension with a passive system. In order to limit the pitch angle and to achieve the improved ride comfort and stability of the vehicle, the vertical displacement of the front and rear body of the half-car model is controlled by the SMC…
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Integrated Model Predictive Control and Adaptive Unscented Kalman Filter for Semi-Active Suspension System Based on Road Classification

China Automotive Technology and Research Center Co., Ltd.-Zhenfeng Wang, Shengjie Xu, Fei Li, Xinyu Wang, Jiansen Yang
Suzhou University of Science and Technology-Jing Miao
  • Technical Paper
  • 2020-01-0999
To be published on 2020-04-14 by SAE International in United States
The accuracy of state estimation and optimal control for controllable suspension system is a challenging task for the vehicle suspension system under various road excitations. How to effectively acquire suspension states and choose the reasonable control algorithm become a hot topic in both academia and industry. Uncertainty is unavoidable for the suspension system, e.g., varying sprung or unsprung mass, suspension damping force or spring stiffness. To tackle the above problems, a novel observer-based control approach, which combines adaptive unscented Kalman filter (AUKF) observer and model predictive control (MPC), is proposed in the paper. A quarter semi-active suspension nonlinear model and road profile model are first established. Secondly, using the road classification identification method based on system response, an AUKF algorithm is employed to estimate accurately the state of suspension system. Due to the nonlinear of semi-active suspension damping force in the movement process, the methods of observer-based and model predictive control are used to design the optimal predictive controller under various road excitations. Finally, compared with passive suspension system, the constrained optimal control (COC) algorithm…
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Robust and optimum design selection for crank train dampers

Mahindra & Mahindra, Ltd.-Anup Bhattacharya, Vivek Yadav, Abhijit Londhe
  • Technical Paper
  • 2020-01-0603
To be published on 2020-04-14 by SAE International in United States
Reduced engine noise and vibrations is a key challenge in product development which leads to better comfort for end customer. Cranktrain is a major contributor in the transfer path of gas oscillations. The noise and vibrations induced by cranktrain torsional resonances are reduced by providing torsional dampers. Dampers are also important for avoiding resonant failures. The requirements from dampers is high reliability, lesser sensitivity for manufacturing variability in rubber properties with respect to desired performance. The requirement from a cranktrain damper is to achieve minimum crankshaft vibratory torque. Also, damper heat dissipation and torsional oscillations need to be within acceptable limits. This depends on selection of damper dimensions, damper hub inertia, ring inertia and rubber stiffness. There is a non-linear dependence of these parameters on damper performance. Hence, it needs an optimizer with better design space exploration capabilities. This paper presents, reliability based optimization process starting with generation of RSM followed by NSGA-II evolutionary search algorithm to achieve robust optimum damper design in early phase of product development through simulation. The process reduced number of…
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Modelling of a combined system of hydraulic magnetorheological fluid damper with braking-by-wire system

Tsinghua University-Cenbo Xiong, Liangyao Yu, Zhenchuan Li, Zhenghong Lu, Abi Lanie
  • Technical Paper
  • 2020-01-0988
To be published on 2020-04-14 by SAE International in United States
A hydraulic chamber is embedded in serial with the accumulator of a normal mono-tube magnetorheological fluid damper (MRFD). The damper stiffness can be adjusted by changing the initial accumulator volume with the hydraulic chamber. This hydraulic chamber is connected to an electric pump and controlled by the braking-by-wire system. Some signals and control parameters of the braking system are shared with the suspension system. A modified bi-viscosity magnetorheological fluid (MRF) model that explicitly includes the parameter of control current is adopted to determine the viscous forces of the damper. A dynamic model of this hydraulic MRFD is subsequently set up based on the hydro dynamic system and the MRF model. In this scheme, both the MRF viscosity and the damper stiffness can be continuously adjusted at the same time. A theoretical model combining the vehicle dynamics, the braking-by-wire system and the hydraulic MRFD is established based on which the control principles of the hydraulic MRFD according to the braking intensity are revealed. Simulations are carried out to study the parametric influences of this combined braking…
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The Effect of Friction on Ride Comfort Simulation and Suspension Optimization

Ebco Inc.-Peijun Xu
Huazhong University of Science and Technology-Wang Xuwang, Xiaoyu Chen, Yunqing Zhang
  • Technical Paper
  • 2020-01-0765
To be published on 2020-04-14 by SAE International in United States
The design of suspension affects the vehicle dynamics such as ride comfort and handling stability. Nonlinear characteristics and friction are important characteristics of suspension system, and the influence on vehicle dynamic performance cannot be ignored. Based on the seven-degree-of-freedom vehicle vibration nonlinear model with friction, the vibration response process of the vehicle and the influence of suspension friction on vehicle ride comfort and suspension action process were studied. The results show that friction will significantly affects the simulation of ride comfort and coincide with the function of the shock absorber. The suspension shock absorbers of vehicles were optimized with and without suspension friction. The results showed that the suspension tended to choose softer shock absorbers when there was friction. However, both of the two optimizations are able to improve the ride comfort of vehicles, and the simulation results were similar. At the same time, it was found that the better the dynamic performance of the vehicle model, the greater the influence of suspension friction on the simulation results of ride comfort.
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Acoustic Characteristics of Automotive Damper during Fluid Structure and Structural Interactions

Gabriel India Ltd.-Ravi B
VIT ARAI-Swapnil S. Kulkarni
  • Technical Paper
  • 2020-01-0989
To be published on 2020-04-14 by SAE International in United States
Acoustic characteristics of hydraulic dampers used in passenger cars are investigated. Experimentation work is carried out with servo hydraulic machine. Semi-anechoic chamber is used to isolate damper in order to study noise source in damper. Noise and vibration data analysis is performed with the help of OROS software. OROS provides noise and vibration testing solution. This is specifically used here for noise and vibration data acquisition and analysis for damper. Noise and vibration tests are performed by various frequencies and amplitude excitation inputs given to damper. As a part of low to mid frequency excitation, the amplitude of damper excitation is 20 mm in rebound and 10 mm in compression stroke of damper with data containing multiple input frequencies namely 0.5, 1, 1.5 and 2 Hz. This test condition ensured that the noise is perceived to car cabin by means of damper rather than filtration unit attached to damper. As a part of high frequency excitation, damper is stroked at low amplitude and high frequency typically ±5 mm in rebound and compression stroke of damper,…
Open Access

Control Performance of Damping and Air Spring of Heavy Truck Air Suspension System with Optimal Fuzzy Control

SAE International Journal of Vehicle Dynamics, Stability, and NVH

Hubei Polytechnic University, China-Vanliem Nguyen, Renqiang Jiao
Southeast University, China-Jianrun Zhang
  • Journal Article
  • 10-04-02-0013
Published 2020-02-28 by SAE International in United States
The air suspension system of heavy trucks not only improves the vehicle’s ride comfort but also reduces the negative impact on the road surface. In order to evaluate the performance of the control damping (CD) and the control air spring (CAS) of the vehicle air suspension system on the ride comfort and the road friendliness, a three-dimensional (3D) nonlinear dynamic model with 14 degrees of freedom (DOF) of the heavy trucks and optimal fuzzy control (OFC) with control rules optimized by the genetic algorithm (GA) are proposed in this study. The root mean square (RMS) acceleration response of the tractor and the dynamic load coefficient (DLC) at the wheel axles are chosen as objective functions under the various operating conditions. Contrastive analysis of the RMS and DLC values with the passive (P), CD, and CAS methods of the air suspension system is carried out respectively. The research result shows that both the CD and CAS methods remarkably improve the ride comfort and road friendliness of the heavy trucks in comparison with P, especially the CAS…
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Transfer Function and Simplified Stiffness Model for Damper Design and Validation

EATON Ltda-André L. A. M. Leão, Bruno C. de Paulo, José I. Piva
  • Technical Paper
  • 2019-36-0229
Published 2020-01-13 by SAE International in United States
The process of vehicular components validation requires field performance verification. During the development process of a component, testing and data collection often require longer than the vehicle test period available for a given component. In order for the vehicle development process to encompass all components tests and software calibration both, cost and time increase. Thus, it has become progressively necessary to use simulation tools and bench analysis during product development processes. Mathematical tools for simulation have been gaining popularity exponentially due to the fact that they enable users to simulate many designs in order to find the optimal solution and reduce development time, prototypes and field tests costs. The present work uses the Signal Analysis Transfer Function Tool, combined with a bar model proposed for calculating stiffness, in the development of a rubber damper and support, as a solution to attenuate the vibration on the electronic module mounted on an automated transmission. The function of the rubber damper is to attenuate the vibration effect of sprung mass and the interactions with vehicle excitation. An important…
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Spring and Damper Tuning of an ATV to Reduce Transmissibility

ARAI Academy-Rajat Girish Kanade, Mohammad Rafiq Agrewale, Kamalkishore Vora
  • Technical Paper
  • 2019-28-2401
Published 2019-11-21 by SAE International in United States
The application in vehicle ride and handling has been mostly subjective or intuitive. There are several methods to improve vehicle stability and handling. One of the methods is suspension tuning. The objective of this work is to perform dynamical analysis of suspension by spring and damper tuning to reduce transmissibility for an all-terrain vehicle. A baseline spring rate data is used for tuning to provide better ride. The Fox air shock absorbers with progressive damping are used for testing. First the dynamics simulation is carried out by using ADAMS CAR tool. A detailed characteristic of the air shocks is obtained at various loading conditions by experimentation using test rig. Based on it, the simulation has been carried out for desired tuning parameters of spring and damper to improve stability. The speculated optimum setting is validated on an all-terrain vehicle (ATV) using ultrasonic sensors, by varying vehicle speed and bump heights to evaluate the transmissibility of the suspension. The acquired data shows behaviour of the suspension and the influence of the main parameters in the transmissibility.…
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Automotive Engineering: November/December 2019

  • Magazine Article
  • 19AUTP11_08
Published 2019-11-01 by SAE International in United States

While I'm among the first media to have driven the mid-engine 2020 Stingray, my time in the car (during the North American Car, Truck and Utility of the Year judging) was but 45 minutes. A very invigorating 45 minutes.

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