scholarly journals Vibration modeling of a vehicle equipped with MR damper and aerodynamic elements

2019 ◽  
Vol 20 (1-2) ◽  
pp. 57-61
Author(s):  
Wiesław Grzesikiewicz ◽  
Michał Makowski

We considered of a vehicle model equipped with controlled magneto-rheological (MR) dampers and controlled aerodynamic elements. The vibrations of the vehicle moving at high speed during acceleration and braking are analysed. The purpose of this analysis is to determine the effect of forces generated on aerodynamic elements on vehicle vibrations and changes in wheel pressure on the road surface during acceleration and braking. The presented work presents the results of numerical investigations obtained on the basis of the developed vehicle model.

Author(s):  
R.B. Soujanya ◽  
D.D. Jebaseelan ◽  
S. Kannan

Passenger’s comfort in moving vehicles depends on the quality of the ride. The major cause of discomfort is the vibration transmitted to passengers due to the road irregularities. For a comfortable ride on a vehicle, vibration must stay within prescribed standards. In the present work, an attempt was made to show that, the vibrations can be limited with the use of Magneto-rheological (MR) dampers for varying road profiles than the passive damping methods. MR dampers are semi-active control devices that use MR fluids to produce controllable damping force as they are known to exhibit nonlinear behaviour. Multi body dynamic studies were done to study the response of the system using a quarter car model. In this paper, passive damping (viscous damping) was considered at natural frequency of 1.012Hz, the response of damping was observed after 10s and the acceleration was found to be 6m/s2. When MR damper is employed as the magnetic force increases, the response of the damping was better than the passive damping, at 1.2A it comes down to 0.55m/s2, and the vibration gets dampened after 1.75s. Hence, from this study it is concluded that the MR damper can be employed in automobile for better ride comfort.


2020 ◽  
Vol 64 (1-4) ◽  
pp. 1439-1445
Author(s):  
Xinna Ma ◽  
Shaopu Yang ◽  
Wenrui Shi

With running speed increases, the dynamics characteristic of railway vehicle system behaves intensively, such as, snaking motion, bifurcation problem, even digression accident. These questions effect ride comfort and run stationary. The magneto-rheological (MR) damper can continually change its state in a few milliseconds and has low energy requirement and insensitivity to the temperature and circumstance. MR dampers have turned out to be a promising device in vibration control. According to the nonlinear of MR damper and the vibration characteristic of semi-active suspension of high-speed vehicle, a seventeen-degree-of-freedom lateral semi-control model of high-speed whole vehicle with MR dampers is established. Taking into account of the vibrations of vehicle and electromagnetic interference, a novel adaptive fuzzy control strategy is put forward. The simulation results show that adaptive fuzzy control method can improve the ride comfort and restrain electromagnetic interference. The electromagnetic interference noise problems in high-speed railway vehicle system with MRD are analyzed and discussed according to EN 55022 for the first time.


Electronics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 193
Author(s):  
Mohamed Ben bezziane ◽  
Ahmed Korichi ◽  
Chaker Abdelaziz Kerrache ◽  
Mohamed el Amine Fekair

As a promising topic of research, Vehicular Cloud (VC) incorporates cloud computing and ad-hoc vehicular network (VANET). In VC, supplier vehicles provide their services to consumer vehicles in real-time. These services have a significant impact on the applications of internet access, storage and data. Due to the high-speed mobility of vehicles, users in consumer vehicles need a mechanism to discover services in their vicinity. Besides this, quality of service varies from one supplier vehicle to another; thus, consumer vehicles attempt to pick out the most appropriate services. In this paper, we propose a novel protocol named RSU-aided Cluster-based Vehicular Clouds protocol (RCVC), which constructs the VC using the Road Side Unit (RSU) directory and Cluster Head (CH) directory to make the resources of supplier vehicles more visible. While clusters of vehicles that move on the same road form a mobile cloud, the remaining vehicles form a different cloud on the road side unit. Furthermore, the consumption operation is achieved via the service selection method, which is managed by the CHs and RSUs based on a mathematical model to select the best services. Simulation results prove the effectiveness of our protocol in terms of service discovery and end-to-end delay, where we achieved service discovery and end-to-end delay of 3 × 10−3 s and 13 × 10−2 s, respectively. Moreover, we carried out an experimental comparison, revealing that the proposed method outperformed several states of the art protocols.


2021 ◽  
pp. 100077
Author(s):  
Samim Mustafa ◽  
Hidehiko Sekiya ◽  
Aya Hamajima ◽  
Iwao Maeda ◽  
Shuichi Hirano

2008 ◽  
Vol 56 ◽  
pp. 218-224
Author(s):  
Maguid H.M. Hassan

Smart control devices have gained a wide interest in the seismic research community in recent years. Such interest is triggered by the fact that these devices are capable of adjusting their characteristics and/or properties in order to counter act adverse effects. Magneto-Rheological (MR) dampers have emerged as one of a range of promising smart control devices, being considered for seismic applications. However, the reliability of such devices, as a component within a smart structural control scheme, still pause a viable question. In this paper, the reliability of MR dampers, employed as devices within a smart structural control system, is investigated. An integrated smart control setup is proposed for that purpose. The system comprises a smart controller, which employs a single MR damper to improve the seismic response of a single-degree-of-freedom system. The smart controller, in addition to, a model of the MR damper, is utilized in estimating the damper resistance force available to the system. On the other hand, an inverse dynamics model is utilized in evaluating the required damper resistance force necessary to maintain a predefined displacement pattern. The required and supplied forces are, then, utilized in evaluating the reliability of the MR damper. This is the first in a series of studies that aim to explore the effect of other smart control techniques such as, neural networks and neuro fuzzy controllers, on the reliability of MR dampers.


1999 ◽  
Author(s):  
Mehdi Ahmadian ◽  
James C. Poynor ◽  
Jason M. Gooch

Abstract This study will examine the effectiveness of magneto-rheological (MR) dampers for controlling shock dynamics. Using a system that includes a 50-caliber rifle and a magneto-rheological damper, it is experimentally shown that MR dampers can be quite effective in controlling the compromise that commonly exists between shock forces and strokes across the shock absorber mechanism. A series of tests are conducted to demonstrate that different damping forces by the MR damper can result in different shock-force/stroke profiles. The test results further show that MR dampers can be used in a closed-loop system to adjust the shock loading characteristics in a manner that fits the dynamic system constraints and requirements.


Author(s):  
Mehdi Ahmadian ◽  
Xubin Song

Abstract A non-parametric model for magneto-rheological (MR) dampers is presented. After discussing the merits of parametric and non-parametric models for MR dampers, the test data for a MR damper is used to develop a non-parametric model. The results of the model are compared with the test data to illustrate the accuracy of the model. The comparison shows that the non-parametric model is able to accurately predict the damper force characteristics, including the damper non-linearity and electro-magnetic saturation. It is further shown that the parametric model can be numerically solved more efficiently than the parametric models.


2018 ◽  
Vol 1 (3) ◽  
pp. 667-678
Author(s):  
Mulyadi Mulyadi ◽  
Muhammad Isya ◽  
Sofyan M. Saleh

Abstract: Blangkejeren - Lawe Aunan road conditions overall is on the slopes of the mountains which is strongly influenced by local environmental factors such as drainage, topography, soil conditions, material conditions and vehicle load conditions across the road. It should be noted in order to avoid a decrease in the road quality due to road surface damage that can affect the traffic safety, comfort and smoothness.. Therefore, it is necessary to study the evaluation of the condition of the damaged road surface and the local factors that affect the damage in order to avoid a decrease in the roads quality. This study took place on Blangkejeren - Lawe Aunan roads started from Sta. 529 + 700 - Sta. 535 + 206. Generally, the condition of roads in this segment were found damage that disturb the comfort, smoothness and safety of the roads users. In this study, the primary data obtained by actual surveys in the form of data field length, width, area, and depth of each type of damage as well as local factors that lead to such damage. Actual field surveys conducted along the 5.506 km, with the distance interval of each segment is 100 m. The secondary data obtained from the relevant institutions and other materials related to this research. This study analyzed the PCI method (Pavement Condition Index) to obtain the level of damage in order to know how to handle, while for the identification of the damage done by observation factors descriptively appropriate observation in the field such as the number of damage points. The results of this study found that the type of damage caused to roads is damage to the cover layer, a hole, and curly. This type of damage that commonly occurs on the road Blangkejeren - Lawe Aunan is damage to the edges with a percentage of 87.30%. The local factors that greatly affect drainage on the percentage of damage is 62.00%. PCI average value is 13.47 which indicates a very bad condition (very poor) and requires maintenance or improvement of reconstruction.Abstrak: Kondisi jalan Blangkejeren – Lawe Aunan secara keseluruhan berada di lereng pegunungan sangat dipengaruhi oleh faktor lingkungan setempat seperti drainase, topografi, kondisi tanah, kondisi material dan kondisi beban kendaraan yang melintasi jalan tersebut. Hal ini perlu diperhatikan agar tidak terjadi penurunan kualitas jalan akibat kerusakan permukaan jalan sehingga dapat mempengaruhi keamanan, kenyamanan, dan kelancaran dalam berlalu lintas. Oleh karena itu, perlu dilakukan penelitian evaluasi terhadap kondisi permukaan jalan yang mengalami kerusakan serta faktor setempat yang mempengaruhi kerusakan tersebut agar tidak terjadi penurunan kualitas jalan. Penelitian ini mengambil lokasi di ruas jalan Blangkejeren – Lawe Aunan yang dimulai dari Sta. 529+700 - Sta. 535+206. Umumnya kondisi ruas jalan pada segmen ini banyak ditemukan kerusakan-kerusakan yang dapat mengganggu kenyamanan, kelancaran, dan keamanan pengguna jalan. Dalam penelitian ini data primer diperoleh dengan melakukan survei aktual lapangan yaitu berupa data panjang, lebar, luasan, dan kedalaman tiap jenis kerusakan serta faktor setempat yang mengakibatkan kerusakan tersebut. Survei aktual lapangan dilakukan sepanjang 5,506 km, dengan jarak interval setiap segmen adalah 100 m. Adapun data sekunder diperoleh dari lembaga terkait dan bahan lainnya yang berhubungan dengan penelitian ini. Penelitian ini dianalisis dengan metode PCI (Pavement Condition Index) untuk mendapatkan tingkat kerusakan agar diketahui cara penanganannya, sedangkan untuk identifikasi faktor kerusakannya dilakukan dengan pengamatan secara diskriptif sesuai hasil pengamatan di lapangan berupa jumlah titik kerusakan. Hasil penelitian ini didapatkan bahwa jenis kerusakan yang terjadi pada ruas jalan adalah kerusakan lapisan penutup, lubang, dan keriting. Jenis kerusakan yang umum terjadi pada ruas jalan Blangkejeren – Lawe Aunan adalah kerusakan tepi dengan persentase 87,30 %. Faktor setempat yang sangat mempengaruhi kerusakan adalah drainase dengan persentase 62,00%. Nilai PCI rata-rata yaitu 13,47 yang menunjukkan kondisi sangat buruk (very poor) dan memerlukan pemeliharaan peningkatan atau rekonstruksi.


Author(s):  
Diane M. Gayeski

While educational and corporate training environments have made large investments in getting wired to high-speed Internet connections, our work and social environments are rapidly becoming more mobile and flexible. The Internet and organizationally based intranets are powerful learning and performance tools, as long as users have a high-speed connection and up-to-date computing equipment. Online learning and information is not nearly as convenient or reliable when learners need to access sites from their homes, hotel rooms, client locations, or while on the road. In corporate settings, large numbers of critical employees such as factory engineers, health care professionals, builders, and maintenance workers often do not even have offices in which to use a computer.


2020 ◽  
Vol 10 (24) ◽  
pp. 8804
Author(s):  
Jhonni Rahman ◽  
Yutaka Shoukaku ◽  
Tomoaki Iwai

This study examines the relationship between rubber-wheel and the contact area on the road surface. Ultraviolet-induced fluorescence microscopy was used to observe and measure the contact parts with pyranine as a dye solution. The high sensitivity to U.V. light makes it easy to distinguish contact and non-contact regions on a very small scale. The experiment was conducted in static and dynamic conditions to identify its influence on the apparent contact area of rubber-wheel and road surface. The in-situ observation of the contact area was captured and recorded using a high-speed digital camera with 1-inch a CMOS (complementary metal oxide semiconductor) sensor. Additionally, the contact area between rubber-wheel and road surface was measured using an analyzing software. The results show differences in static and dynamic contact conditions based on the operating parameters.


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