scholarly journals Road Vehicle-Bridge Interaction considering Varied Vehicle Speed Based on Convenient Combination of Simulink and ANSYS

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Helu Yu ◽  
Bin Wang ◽  
Yongle Li ◽  
Yankun Zhang ◽  
Wei Zhang

In order to cover the complexity of coding and extend the generality on the road vehicle-bridge iteration, a process to solve vehicle-bridge interaction considering varied vehicle speed based on a convenient combination of Matlab Simulink and ANSYS is presented. In this way, the road vehicle is modeled in state space and the corresponding motion equations are solved using Simulink. The finite element model for the bridge is established and solved using ANSYS. The so-called inter-history iteration method is adopted to realize the interaction between the vehicle model and the bridge model. Different from typical method of road vehicle-bridge interaction in the vertical direction, a detailed longitudinal force model is set up to take into account the effects of varied vehicle speed. In the force model, acceleration and braking of the road vehicle are treated differently according to their mechanical nature. In the case studies based on a simply supported beam, the dynamic performance of the road vehicle and the bridge under varied vehicle speeds is calculated and discussed. The vertical acceleration characteristics of the midpoint of beam under varied vehicle speed can be grouped into two periods. The first one is affected by the load transform between the wheels, and the other one depends on the speed amplitude. Sudden change of the vertical acceleration of the beam and the longitudinal reaction force are observed as the wheels move on or off the bridge, and the bridge performs different dynamic responses during acceleration and braking.

Author(s):  
Tom Partridge ◽  
Lorelei Gherman ◽  
David Morris ◽  
Roger Light ◽  
Andrew Leslie ◽  
...  

Transferring sick premature infants between hospitals increases the risk of severe brain injury, potentially linked to the excessive exposure to noise, vibration and driving-related accelerations. One method of reducing these levels may be to travel along smoother and quieter roads at an optimal speed, however this requires mass data on the effect of roads on the environment within ambulances. An app for the Android operating system has been developed for the purpose of recording vibration, noise levels, location and speed data during ambulance journeys. Smartphone accelerometers were calibrated using sinusoidal excitation and the microphones using calibrated pink noise. Four smartphones were provided to the local neonatal transport team and mounted on their neonatal transport systems to collect data. Repeatability of app recordings was assessed by comparing 37 journeys, made during the study period, along an 8.5 km single carriageway. The smartphones were found to have an accelerometer accurate to 5% up to 55 Hz and microphone accurate to 0.8 dB up to 80 dB. Use of the app was readily adopted by the neonatal transport team, recording more than 97,000 km of journeys in 1 year. To enable comparison between journeys, the 8.5 km route was split into 10 m segments. Interquartile ranges for vehicle speed, vertical acceleration and maximum noise level were consistent across all segments (within 0.99 m . s−1, 0.13 m · s−2 and 1.4 dB, respectively). Vertical accelerations registered were representative of the road surface. Noise levels correlated with vehicle speed. Android smartphones are a viable method of accurate mass data collection for this application. We now propose to utilise this approach to reduce potential harmful exposure, from vibration and noise, by routing ambulances along the most comfortable roads.


Author(s):  
S. C¸ag˘lar Bas¸lamıs¸lı ◽  
Selis O¨nel

In this study, the Shannon entropies of six different road-profiles ranging from “very good asphalt road” to “dirt road (terrain)” were calculated. Results indicate that each type of road has a well defined entropy value and that the entropies of roads ranging from “very good asphalt” to “dirt road (terrain)” lie on a nearly linear locus. A second approach presented in this paper consists in measuring the sprung mass vertical acceleration of a vehicle running over segments of roads of different qualities and calculating the entropies of the acceleration signals. This procedure has been applied to assess the influence of nonlinear damping and vehicle speed. It has been seen that it is possible to identify the type of the road surface through the calculation of entropy if the vehicle operating parameters are known. Finally, it is observed that the locus of entropy values is concave on the plot of acceleration entropy versus root mean square (RMS) acceleration.


2014 ◽  
Vol 592-594 ◽  
pp. 2165-2178 ◽  
Author(s):  
M.W. Trikande ◽  
Vinit V. Jagirdar ◽  
Muraleedharan Sujithkumar

Comparative performance of vehicle suspension system using passive, and semi-active control (on-off and continuous) has been carried out for a multi-axle vehicle under the source of road disturbance. Modelling and prediction for stochastic inputs from random road surface profiles has been carried out. The road surface is considered as a stationary stochastic process in time domain assuming constant vehicle speed. The road surface elevations as a function of time have been generated using IFFT. Semi active suspension gives better ride comfort with consumption of fraction of power required for active suspension. A mathematical model has been developed and control algorithm has been verified with the purpose/objective of reducing the unwanted sprung mass motions such as heave, pitch and roll. However, the cost and complexity of the system increases with implementation of semi-active control, especially in military domain. In addition to fully passive and fully semi-active a comparison has been made with partial semi-active control for a multi-axle vehicle to obviate the constraints. The time domain response of the suspension system using various control logics are obtained and compared. Simulations for different class of roads as defined in ISO: 8608 have been run and the ride comfort is evaluated and compared in terms of rms acceleration at CG in vertical direction (Z), which is the major contributor for ORV (Overall Ride Value) Measurement.


2020 ◽  
pp. 002029402098140
Author(s):  
Qingfei Gao ◽  
Kun Zhang ◽  
Tong Wang ◽  
Weikang Peng ◽  
Chengqing Liu

The steel-concrete composite girder bridge is a new type of bridge. The steel girder and concrete slab are connected together by connectors and bear the common force so that the tensile performance of steel and the compressive performance of concrete can be fully utilized. The advantages are obvious. However, research on the dynamic analysis of steel-concrete composite beam bridges is still relatively rare, and the dynamic effects on these bridges from vehicles are becoming increasingly significant. In this paper, a more complex steel-concrete composite simply supported beam bridge model and the entire vehicle model are established, and five steel-concrete connection levels of the bridge model are considered. Using the finite element model, the effects of five factors, namely, bridge natural frequency, vehicle natural frequency, vehicle speed, vehicle lateral position and bridge deck roughness, on the dynamic load allowance ( DLA) of the composite girder bridge are studied. The influence of vehicle speed and bridge surface roughness on the DLA has a strong regularity. The change in the DLA of the lateral position of the vehicle is highly symmetrical, and the DLA value at the side beam is larger than that of the center beam. Changes in bridge vibration frequency and vehicle vibration frequency can bring about significant changes in the DLA, and the closer the two frequencies are, the more significant the DLA increases, and the more likely it is to produce resonance.


2011 ◽  
Vol 90-93 ◽  
pp. 1931-1935
Author(s):  
Shi Tan Gu ◽  
Chun Qiu Wang ◽  
Chun Zhao Xu ◽  
Feng Hai Yu

A number of nodes at different strata positions of tunnel roof were selected as research objects, the law between the roof deformation and the speed or acceleration time-history of horizontal and vertical direction were simulated on conditions of inputting earthquake wave at particular lacation of deep tunnel floor. With the gradually increasing distance from tunnel top surface, the “high -low-high” law of peak values were performed in speed time-history and acceleration speed time-history curves. One peak value was overally performed on vertical speed time-history curves, but multiple peak fluctuation was indicated in vertical acceleration time-history, horizontal speed and horizontal accelaration time-history curves.


Vibration ◽  
2018 ◽  
Vol 1 (1) ◽  
pp. 20-40 ◽  
Author(s):  
Abdulaziz Alfadhli ◽  
Jocelyn Darling ◽  
Andrew Hillis

The use of suspension preview information obtained from a quarter vehicle model (QvM) to control an active seat has been shown by the authors to be very promising, in terms of improved ride comfort. However, in reality, a road vehicle will be subjected to disturbances from all four wheels, and therefore the concept of preview enhanced control should be applied to a full vehicle model. In this paper, different preview scenarios are examined, in which suspension data is taken from all or limited axles. Accordingly, three control strategies are hypothesized—namely, front-left suspension (FLS), front axle (FA), and four wheel (4W). The former utilises suspension displacement and velocity preview information from the vehicle suspension nearest to the driver’s seat. The FA uses similar preview information, but from both the front-left and front-right suspensions. The 4W controller employs similar preview information from all of the vehicle suspensions. To cope with friction non-linearities, as well as constraints on the active actuator displacement and force capabilities, three optimal fuzzy logic controllers (FLCs) are developed. The structure of each FLC, including membership functions, scaling factors, and rule base, was sequentially optimised based on improving the seat effective amplitude transmissibility (SEAT) factor in the vertical direction, using the particle swarming optimisation (PSO) algorithm. These strategies were evaluated in simulation according to ISO 2631-1, using different road disturbances at a range of vehicle forward speeds. The results show that the proposed controllers are very effective in attenuating the vertical acceleration at the driver’s seat, when compared with a passive system. The controller that utilised suspension preview information from all four corners of the car provided the best seat isolation performance, independent of vehicle speed. Finally, to reduce the implementation cost of the “four suspension” controller, a practical alternative is developed that requires less measured preview information.


2014 ◽  
Vol 1022 ◽  
pp. 169-181
Author(s):  
Yu Han ◽  
Guang Wei Meng ◽  
Chao Sheng Huang ◽  
Yan Hao

To study the problem of the road identification of the off-road vehicle, a road identification method based on on-line monitoring of the vehicle running state was put forward. The time series data of the suspension displacement and the sprung mass were monitored. The spatial power spectrum density was calculated, aiming at automatically identifying the road roughness. The vehicle speed and the longitudinal vibration acceleration were collected, aiming at identifying the terrain slope. The state of the vehicle and engine was recorded. The rolling resistance coefficient was computed, based on the output torque of the engine. Comparing this coefficient with the threshold of the soft road surface, the soft road surface could be identified. On the basis of the identification result of the road feature, the vehicle running mode can be adjusted, improving the maneuverability of the off-road vehicle.


2020 ◽  
Vol 64 (1-4) ◽  
pp. 1365-1372
Author(s):  
Xiaohui Mao ◽  
Liping Fei ◽  
Xianping Shang ◽  
Jie Chen ◽  
Zhihao Zhao

The measurement performance of road vehicle automatic weighing instrument installed on highways is directly related to the safety of roads and bridges. The fuzzy number indicates that the uncertain quantization problem has obvious advantages. By analyzing the factors affecting the metrological performance of the road vehicle automatic weighing instrument, combined with the fuzzy mathematics theory, the weight evaluation model of the dynamic performance evaluation of the road vehicle automatic weighing instrument is proposed. The factors of measurement performance are summarized and calculated, and the comprehensive evaluation standard of the metering performance of the weighing equipment is obtained, so as to realize the quantifiable analysis and evaluation of the metering performance of the dynamic road vehicle automatic weighing instrument in use, and provide data reference for adopting a more scientific measurement supervision method.


2021 ◽  
Vol 13 (2) ◽  
pp. 168781402199497
Author(s):  
Guanghui Xu ◽  
Shengkai Su ◽  
Anbin Wang ◽  
Ruolin Hu

The increase of axle load and train speed would cause intense wheelrail interactions, and lead to potential vibration related problems in train operation. For the low-frequency vibration reduction of a track system, a multi-layer track structure was proposed and analyzed theoretically and experimentally. Firstly, the analytical solution was derived theoretically, and followed by a parametric analysis to verify the vibration reduction performance. Then, a finite element simulation is carried out to highlight the influence of the tuned slab damper. Finally, the vibration and noise tests are performed to verify the results of the analytical solution and finite element simulation. As the finite element simulation indicates, after installation of the tuned slab damper, the peak reaction force of the foundation can be reduced by 60%, and the peak value of the vertical vibration acceleration would decrease by 50%. The vibration test results show that the insertion losses for the total vibration levels are 13.3 dB in the vertical direction and 21.7 dB in the transverse direction. The noise test results show that the data of each measurement point is smoother and smaller, and the noise in the generating position and propagation path can be reduced by 1.9 dB–5.5 dB.


2021 ◽  
Vol 11 (2) ◽  
pp. 196
Author(s):  
Sébastien Laurent ◽  
Laurence Paire-Ficout ◽  
Jean-Michel Boucheix ◽  
Stéphane Argon ◽  
Antonio Hidalgo-Muñoz

The question of the possible impact of deafness on temporal processing remains unanswered. Different findings, based on behavioral measures, show contradictory results. The goal of the present study is to analyze the brain activity underlying time estimation by using functional near infrared spectroscopy (fNIRS) techniques, which allow examination of the frontal, central and occipital cortical areas. A total of 37 participants (19 deaf) were recruited. The experimental task involved processing a road scene to determine whether the driver had time to safely execute a driving task, such as overtaking. The road scenes were presented in animated format, or in sequences of 3 static images showing the beginning, mid-point, and end of a situation. The latter presentation required a clocking mechanism to estimate the time between the samples to evaluate vehicle speed. The results show greater frontal region activity in deaf people, which suggests that more cognitive effort is needed to process these scenes. The central region, which is involved in clocking according to several studies, is particularly activated by the static presentation in deaf people during the estimation of time lapses. Exploration of the occipital region yielded no conclusive results. Our results on the frontal and central regions encourage further study of the neural basis of time processing and its links with auditory capacity.


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