Optimization of Vehicle Powertrain Mounting System and its Performance

2013 ◽  
Vol 441 ◽  
pp. 580-583
Author(s):  
Gong Yu Pan ◽  
Xin Yang ◽  
You Yan

In order to solve the vibration problem of diesel engine powertrain assembly at its idle state, a six degree-of-freedom dynamics model of the powertrain mounting system is established and a optimization based on Adams/View is applied to simulation and analysis on the powertrain mounting system with energy decoupling method. The results show that the optimized repositioning mounts installation position can effectively improve decoupling rate in main vibration directions of mounting system. Based on this, the vibration transmissibility and acceleration response before and after optimization are simulated. The results show that the optimized engine mounting system makes a great improvement of vibration isolation performance.

2013 ◽  
Vol 328 ◽  
pp. 499-503 ◽  
Author(s):  
Gong Yu Pan ◽  
You Yan ◽  
Xin Yang

In order to solve the vibration problem of diesel engine powertrain assembly at its idle state, a six degree-of-freedom dynamics model of the powertrain mounting system is established and a optimization based on Adams/View is applied to simulation and analysis on the powertrain mounting system with energy decoupling method. The results show that the optimized repositioning mounts installation position can effectively improve decoupling rate in main vibration directions of mounting system, proving that the energy decoupling method has good effect on greatly improving the system’s vibration isolation efficiency.


2018 ◽  
Vol 14 (6) ◽  
pp. 155014771878237 ◽  
Author(s):  
Shuilong He ◽  
Binqiang Chen ◽  
Zhansi Jiang ◽  
Yanxue Wang ◽  
Fuyun Liu

Strong steering wheel jitter during idling states of the engine can seriously deteriorate the driving comfort as well as the driving safety. The powertrain suspension system can be considered as the only essential path for the transmission of vibrations from the engine to the vehicle cab. Its vibration isolation performance directly affects the severity of vibrations on the steering wheel. In this article, aiming at solving the problem of a certain type of commercial vehicle’s steering wheel with strong idle jitter at the idle state, the intrinsic characteristics and vibration isolation performances of the powertrain suspension system were studied in detail. A multi-sensor-based measurement strategy was utilized to evaluate the idle jitter severity of the steering wheel. In order to improve the indicators of the decoupling degree, the vibration transmissibility, and the resonant frequency distributions of the engine suspension system, an optimization model of engine suspension system was established. Parameters of the optimized suspension system were obtained by multi-objective particle swarm optimization. Finally, the effectiveness and feasibility of the optimization algorithm to solve the problem of the vehicle’s steering wheel jitter at idle states were verified through a test using multiple acceleration sensors, which has practical values in the engineering field.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Xingtian Liu ◽  
Changbao Shao ◽  
Liping Zhou ◽  
Xiangsen Kong

In order to provide an ultraquiet environment for spacecraft payload, a six-degree-of-freedom microvibration isolation device for satellite control moment gyro (CMG) is proposed in this paper. The dynamic characteristics of the microvibration isolation device are analyzed theoretically and experimentally. The dynamic equations of the microvibration suppression device are established by using the Newton–Euler method. The dynamic responses are numerically solved and the frequency-domain characteristics of the microvibration isolation device under base excitation are analyzed. The analytical results are first verified numerically, and the two results are in good accordance. The experimental apparatus is built, and the vibration isolation performance is investigated. The acceleration transfer function is measured and the influence of the excitation amplitude on the vibration isolation performance is performed. It is shown that the amplification factor at the vicinity of the resonance frequency is within 10 dB, and the vibration isolation performance is significant at higher frequencies. The vibration attenuation performance at the main frequency of the CMG (100 Hz) is more than 30 dB. The microvibration suppression device can effectively suppress the microvibration generated by CMG during orbital operation.


Author(s):  
Xuancheng Yuan ◽  
Shengyang Zhu ◽  
Lei Xu ◽  
Wanming Zhai ◽  
Huailong Li

Floating slab track is an effective countermeasure to mitigate undesirable vibrations caused by metro trains. In this work, a stochastic fractional derivative model is proposed for simulating the dynamic behavior of rubber bearings in floating slab tracks. The stochastic fractional derivative model is based on the Grünwald representation of fractional calculus, the number theoretical method, and the probability density evolution method (PDEM). It considers the viscoelastic characteristics of the rubber bearings, as well as randomness in mechanical behavior due to manufacturing tolerances, aging, and fatigue. The stochastic fractional derivative model is then implemented into a vehicle–floating slab track coupled dynamics model to investigate the vibration isolation performance of the floating slab track with rubber bearings. The characteristics and advantages of the stochastic fractional derivative model with deterministic parameters are illustrated by comparing the results with the conventional Kelvin model. Finally, stochastic analyses of the dynamic response and the vibration isolation performance of the floating slab track are carried out using the coupled vehicle–floating slab track system dynamics model. Results show that the stochastic simulation of the vehicle–floating slab track system using PDEM is efficient and reliable compared with the Monte Carlo method. Thus, the proposed model is effective and useful for evaluating the vibration levels in floating slab tracks with uncertain parameters, and for predicting the reliability of the vibration isolation performance.


2002 ◽  
Vol 21 (3) ◽  
pp. 141-155 ◽  
Author(s):  
R.G. Dong ◽  
T.W. McDowell ◽  
D.E. Welcome ◽  
S. Rakheja ◽  
S. A. Caporali ◽  
...  

Anti-vibration gloves have been used as personal protective equipment to reduce the exposure intensity of hand-transmitted vibration. Although a method based upon the measured transfer function has been recently proposed to predict the tool-specific anti-vibration performance of these gloves, its validity for real tool applications has not been sufficiently evaluated. In this study, the effectiveness of the proposed prediction method was examined using two typical vibration-attenuation gloves when used in conjunction with two different pneumatic chipping hammers. Six adult male subjects were employed in the experiments involving measurement of gloves transmissibility while operating the selected tools. A comparison of the measured vibration transmissibility with the predicted values revealed that the transfer function method provides a reasonably good prediction of the vibration isolation performance of the gloves. The differences between the predicted and measured mean values of the weighted transmissibility were surprisingly small. It is concluded that the transfer function method can serve as an effective and convenient approach for estimating the effectiveness of anti-vibration gloves when used with pneumatic chipping hammers. A pneumatic chipping hammer is considered to represent a critical case for the evaluation of the method because they are typical percussive tools that generate impact vibration. It is thus anticipated that the transfer function method may also be widely employed to predict anti-vibration glove performance when used with many other vibrating tools.


Author(s):  
Hui Liu ◽  
Xiaojie Wang ◽  
Weida Wang ◽  
Changle Xiang

This paper proposes a torsion isolator with negative stiffness structures, which has low stiffness. The torsion isolator has been designed into disk structure, which is the installation position of the positive springs and negative stiffness structures. In this paper, the model of the torsion isolator is introduced firstly, and the nonlinear stiffness and torque are studied under different compression deformation of springs in negative stiffness structures. Then a two-degree-freedom equation of the torsional isolator is established and vibration transmissibility is obtained by using Harmonic Balance Method. Theoretical analysis results show that the isolator with negative stiffness structures has larger isolation frequency range than linear isolator. Finally, an initial experiment is completed. The experimental results show that the isolator has a good vibration isolation performance.


2021 ◽  
pp. 095745652110557
Author(s):  
Yong Chen ◽  
Mian Jiang ◽  
Daoyong Wang ◽  
Kuanfang He

The mass variances of materials in buckets and the movements of excavation arms greatly impact powertrain vibration transmissibility in hydraulic excavators under working conditions. If the influence of mass variation among bucket contents and excavation arm motions on vibration transmissibility is not considered, then only limited improvements can be made to vibration isolation performance. In this paper, vibration transmissibility suppression for hydraulic excavators operating under working conditions were studied via multi-objective optimization for stiffness coefficients of suspension elements (SEs). First, the rigid-flexible coupling model of a hydraulic excavator with a flexible base was built using ADAMS software. In the model, the stiffness coefficients of the SEs were the targeted variables with constrained conditions, while the multi-objectives for optimization were the vibration transmissibility and energy decoupling rates of the powertrain. Vibration isolation transmissibility (VIT) of the mounting system was compared between situations with non-optimized and optimized stiffness coefficients. Finally, the amplitude changes of the resultant SE support forces were used to illustrate the effects of powertrain vibration transmissibility suppression. We found that the average value of VITs increases significantly during the optimization process for the stiffness coefficients of SEs, which indicates that the mounting system has better vibration isolation performance. The smaller amplitudes of the resultant support force illustrate the improvements to the performance of vibration transmissibility suppression of the powertrain via the optimization process.


2021 ◽  
Vol 13 (8) ◽  
pp. 168781402110449
Author(s):  
Xin Liao ◽  
Xiaofei Du ◽  
Shaohua Li

In order to improve the vibration isolation performance of cab seat and ride comfort of the driver, a seat suspension structure of construction machinery cab is proposed based on negative stiffness structure (NSS) in this paper. The influences of different parameters of suspension system on dynamic stiffness are analyzed. The configuration parameter range of suspension system is obtained. Then, the nonlinear dynamic equation of the seat suspension system is established and the NSS optimization model is proposed. The vibration transmissibility characteristics of suspension structure are analyzed by different methods. The results show that the displacement and acceleration amplitude of optimized seat suspension system are obviously reduced, and the VDV and RMS in the vertical vibration direction for the seat are respectively decreased by 87% and 86%. The vibration transmissibility rate SEAT and the Ttrans are both decreased. Moreover, the peak frequencies of the vibration transmitted to the driver are not near the key frequency values which are easy to cause human discomfort. It indicates that the design of seat suspension system has no effect on the health condition of the driver after being vibrated. The advantages of vibration isolation performance of the designed NSS suspension system are demonstrated, improving the driver’s ride comfort and the working environment.


2017 ◽  
Vol 21 (3) ◽  
pp. 1119-1132 ◽  
Author(s):  
Gui-Lan Yu ◽  
Hong-Wei Miao

The vibration isolation performance of a PC sandwich plate with periodic hollow tube core is investigated experimentally and numerically. The experiment results reveal that there exist vibration attenuation zones in acceleration frequency responses which can be improved by increasing the number of periods or tuning some structure parameters. The presence of soft fillers shifts the attenuation zone to lower frequencies and enhances the capability of vibration isolation to some extent. Dispersion relations and acceleration frequency responses are calculated by finite element method using COMSOL MULTIPHYSICS. The attenuation zones obtained by experiments fit well with that by simulations, and both are consistent with the band gap in dispersion relations. The numerical and experimental studies in the present paper show that this PC sandwich plate exhibits a good performance on vibration isolation in low frequency ranges, which will provide some useful references for relevant research and potential applications in vibration propagation manipulations.


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