Analysis for Ride Comfort Evaluation of Passenger Car Traveling on Roads with Generalized Road Profiles and Conventional Speeds

2014 ◽  
Vol 926-930 ◽  
pp. 877-880
Author(s):  
Ai Hua Tang ◽  
Jian Ping Tian ◽  
Ying Hua Liao

To investigate how the conventional speeds to affect passenger cars ride comfort under a kind of road surface profiles, in multibody dynamics software (ADAMS/Car), a vehicle model was built based on the characteristic parameters of a passenger car. According to the relevant test regulations of ride comfort, the building methods of road surface profiles were discussed. Furthermore, a dynamics simulation analysis of the car was realized by ADAMS/Car and the acceleration-time histories of the seat surfaces X/Y/Z-axis under three conventional driving-speeds were acquired. A special MATLAB program was compiled to calculate the total weighted Root Mean Square (RMS) value by calling the above histories. According to the GB/T 4970-1996, a road test of a passenger car was carried out in the random road surface which equivalent to B level. The car was driven to get the values of total weighted acceleration RMS under three conventional driving-speeds. By comparing the road test result with simulation, the result indicated that the changing trend of total weighted RMS value is consistent as the driving-speed changes, and the ride comfort will decrease when the driving-speed increase. At the same time, it shows that the consistency of the simulation and road test is better.

2019 ◽  
Vol 178 (3) ◽  
pp. 228-234
Author(s):  
Wojciech GIS ◽  
Maciej GIS ◽  
Piotr WIŚNIOWSKI ◽  
Mateusz BEDNARSKI

Air pollution is a challenge for municipal authorities. Increased emission of PM10 and PM 2.5 particles is particularly noticeable in Poland primarily the autumn and winter period. That is due to the start of the heating season. According to the above data, road transport accounted for approximately 5% of the creation of PM10 particles, ca. 7% of PM2.5 and approximately 32% for NOx. In Poland, suspended particles (PM10 and PM2.5) cause deaths of as many as 45,000 people a year. The issue of smog also affects other European cities. Therefore, it is necessary to undertake concrete efforts in order to reduce vehicle exhaust emissions as much as possible. It is therefore justifiable to reduce the emission of exhaust pollution, particularly NOx, PM, PN by conventional passenger cars powered by compression ignition engines. Emissions by these passenger cars have been reduced systematically. Comparative tests of the above emission of exhaust pollution were conducted on chassis dynamometer of such passenger car in NEDC cycle and in the new WLTC cycle in order to verify the level of emissions from this type of passenger car. Measurements of fuel consumption by that car were also taken. Emission of exhaust pollution and fuel consumption of the this car were also taken in the RDE road test.


2013 ◽  
Vol 395-396 ◽  
pp. 1142-1145 ◽  
Author(s):  
Ai Hua Tang

The arising health problems of ride comfort of passenger cars point out that a lot of effort still has to be put into the design of passive suspension systems.The comfort problem originates from the vibrations transmitted to the driver and passengers caused by the unevenness of the road. This paper reports on an investigation to determine the spring and damper settings that will ensure optimal ride comfort of a passenger car at different speeds. D-optimal designs are developed via multibody dynamics software (ADAMS/Insight) with a model. Evaluation of the comfort improvement was done using an objective function according to the international organisation for standardisation (ISO)2631(1997). The optimised passive suspensions equipped in a passenger car were tested on a test rig in ADAMS/Car. The results show that the vibration levels can be reduced by 47%, generating a drastic comfort improvement.


Author(s):  
Sang-Kwon Lee ◽  
Dong-June Yu

A few researchers have tried to find the measurement of the reverberation time of a passenger car. However, this has proved to be extremely difficult because the reverberation time of a passenger car is too short to measure using the traditional bandpass filter. If the reverberation time is very short, the product of the reverberation time ( T) and the bandwidth ( B) of the traditional bandpass filter is very small. The low level of the product BT required for the measurement of the reverberation time using the traditional bandpass filter is 16. In order to overcome this problem, the wavelet filter bank has been developed. In the paper, this new wavelet filter is employed to measure the reverberation times of five different classes of passenger car. The low level of the product BT required for the measurement of reverberation time using the wavelet filter is 4. Therefore, it was possible to measure the reverberation times of five passenger cars successfully using the new wavelet filter bank. It is found that the reverberation times measured in most passenger cars are around 0.04. It is a very short reverberation time compared with those of general acoustic rooms like a concert hall.


2012 ◽  
Vol 215-216 ◽  
pp. 399-406
Author(s):  
Xiao Ming Du ◽  
Jin Dong Ren ◽  
Yong Qing Liu ◽  
Zhong Xian Chen ◽  
Shi Hai Li ◽  
...  

Ergonomics is an important validation content in vehicle product development. The traditional evaluation method of ergonomics adopts physical mockups or prototypes, which is very costly, and is inconvenient to modify, and usually cause prolonged development cycle-time. In this paper, in conjunction with enterprise’s requirements, an ergonomic validation equipment system, which has adjustable main parts, was developed. Firstly, requirements were analyzed, and target model cars ranges were determined, and ergonomic contents which can be validated using this equipment were clarified. The packaging characteristic of the passenger car was analyzed, and the reference fiducial marks system used for packaging design were determined. Based on the requirement of occupant accommodation, anthropometries of target population were statistically analyzed. By using revised SAE J1517 H-Point curves models, the drivers’ seating space was designed, as well as the requirement of the driver seat track travel. Based on the analysis of packaging data of passenger cars, and considering the possible changes, controls such as steering wheel, pedals, sticks, etc., were packaged.


2018 ◽  
Vol 19 (11) ◽  
pp. 3405 ◽  
Author(s):  
Emanuel Peter ◽  
Jiří Černý

In this article, we present a method for the enhanced molecular dynamics simulation of protein and DNA systems called potential of mean force (PMF)-enriched sampling. The method uses partitions derived from the potentials of mean force, which we determined from DNA and protein structures in the Protein Data Bank (PDB). We define a partition function from a set of PDB-derived PMFs, which efficiently compensates for the error introduced by the assumption of a homogeneous partition function from the PDB datasets. The bias based on the PDB-derived partitions is added in the form of a hybrid Hamiltonian using a renormalization method, which adds the PMF-enriched gradient to the system depending on a linear weighting factor and the underlying force field. We validated the method using simulations of dialanine, the folding of TrpCage, and the conformational sampling of the Dickerson–Drew DNA dodecamer. Our results show the potential for the PMF-enriched simulation technique to enrich the conformational space of biomolecules along their order parameters, while we also observe a considerable speed increase in the sampling by factors ranging from 13.1 to 82. The novel method can effectively be combined with enhanced sampling or coarse-graining methods to enrich conformational sampling with a partition derived from the PDB.


2018 ◽  
Vol 9 (1) ◽  
pp. 2 ◽  
Author(s):  
Peter Speers

Hydrogen Mobility Europe (H2ME, 2015–2022) is the largest European Fuel Cells and Hydrogen Joint Undertaking (EU FCH JU)-funded hydrogen light vehicle and infrastructure demonstration. Up until April 2017, the 40 Daimler passenger car fuel cell electric vehicles (FCEVs) and 62 Symbio Fuel Cell-Range Extended Electric Vans (FC-REEV)-vans deployed by the project drove 625,300 km and consumed a total of 7900 kg of hydrogen with no safety incidents. During its first year of operation (to April 2017), the NEL Hydrogen Fueling HRS (hydrogen refuelling station) in Kolding, Denmark dispensed 900 kg of hydrogen, and demonstrated excellent reliability (98.2% availability) with no safety incidents. The average hydrogen refuelling time for passenger cars is comparable to that for conventional vehicles (2–3 min).


2019 ◽  
Author(s):  
Jose Daniel Arroyo

The iconic Ford Motor Company is considered one of the pillars of the automotive industry. Its first vehicle, the Model T, introduced the concept of mass production and automobile affordability to the masses. Today, the market is full of domestic and foreign competitors, yet, Ford has struggled to remain competitive, even though it promotes itself as America’s best-selling brand. Its stock was recently downgraded, and recently, it announced its intentions to only sell sports utility vehicles, trucks, Mustangs and Focus, in other words, it will stop selling most of its passenger cars. Conversely, Toyota continues to lead the market in passenger car sales, while newcomer Tesla struggles to deliver on its backlog of 500,000 electric vehicle orders. Ford has strong brand equity, has automated production facilities and a large franchised dealer network across the globe. Yet, it is rapidly losing passenger car market share, its profits are eroding, and its new vision is confusing. Furthermore, the company is facing a significant threat from well capitalized new competitors entering from the tech industry. The company, on the other hand, has enjoyed significant success in mainland China, where the demand for American automobiles continuous to be strong. Yet, the company needs to assume a cost leadership position and attempt to use this strategy to increase market share. The contention in this paper is that an adequate approach for the company appears to be a combination of market penetration in the domestic front, market expansion in Asia and other parts of the globe, and a product development approach that ushers cost reductions.


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