RESEARCH INTO AUTOMOBILE MOVEMENT ON A CURVE UNDER WINTER CONDITIONS / AUTOMOBILIO JUDĖJIMO POSŪKYJE TYRIMAS ŽIEMOS SĄLYGOMIS

The article analyzes the movement of the car on the curve on the slippery and snowy road surface with asphalted ruts. The paper reviews literature related to lateral and longitudinal vehicle acceleration and dynamics of vehicle movement. The experimental facts of vehicle lateral acceleration are given in graphical charts. The article also describes the acceleration values and stability of the automobile depending on the speed in the curve. The findings are given based on the results. Santrauka Straipsnyje nagrinėjamas automobilio judėjimas posūkyje esant slidžiai ir snieguotai su asfaltuotomis provėžomis kelio dangai. Apžvelgiama literatūra, susijusi su automobilių skersiniais ir išilginiais pagreičiais, automobilių judėjimo dinamika. Eksperimentinėje dalyje pateikiami automobilių skersinių pagreičių grafikai. Nagrinėjamas pagreičių dydis ir automobilio stabilumas priklausomai nuo judėjimo greičio tame kelio posūkyje. Remiantis gautais rezultatais pateikiamos išvados.

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Assessment of roadability and stability of a vehicle movement on the bend

10.36652/1684-1298-2020-11-22-29 ◽

2020 ◽

Keyword(s):

Mathematical Model ◽

Road Surface ◽

Inertia Force ◽

Speed Limit ◽

The Road ◽

Inertial Moment ◽

The Mathematical Model ◽

Computer Imitation ◽

Vehicle Movement

The paper presents the mathematical model and the technique of computer imitation of a vehicle movement on bend. Research of roadability and stability of the truck and the schedules illustrating change of characteristics of the steered movement have been obtained. The critical modes of the movement causing separation of wheels from road surface and side slippage have been defined. Speed limit of the steered movement on trajectory of the set curvature have been determined. Keywords vehicle, wheel, cross and longitudinal reactions of the road, inertia force, inertial moment, trajectory of a vehicle movement, angles of withdrawal of wheels, spring weight angle of heel, side slippage, vehicle drift

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Access Spacing Based on Turning-Vehicle Acceleration

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2618-01 ◽

2017 ◽

Vol 2618 (1) ◽

pp. 1-7

Author(s):

James L. Gattis ◽

Justin R. Chimka ◽

Andrew Evans

Keyword(s):

Small Study ◽

Access Management ◽

Left Turn ◽

The Core ◽

Different Types ◽

Vehicle Acceleration ◽

Time Required ◽

Vehicle Movement ◽

Suburban Environment

Spacing between access connections—whether between a public roadway and a driveway or between two successive driveways—is one of the core techniques employed to effect access management. Several rationales reflecting different types of traffic interactions have been developed as a basis for minimum spacing distances. A small study was done in which two attributes were recorded: positions of vehicles turning from a side street and accelerating along the through roadway and time required for vehicles to turn left from the through roadway into a driveway. The vehicle movement described—a vehicle turning right from the side street into the through roadway—may be more likely to surprise the driver contemplating a left turn from the through roadway. Information derived from these observations, combined with perception–reaction values found in the literature, offers a basis for minimum spacing criteria that addresses one of many types of traffic interactions related to spacing, where a left turn is allowed across the through roadway downstream of another connection. These findings provide one more means to assess spacing along four-lane arterials in a developed suburban environment. A study with a greater scope to expand these findings is also proposed.

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ABOUT THE APPROACHES TO MATHEMATICAL DESCRIPTION AND CALCULATION OF TIRE ROUAD NOISE RADIATION

Akustika ◽

10.36336/akustika20193297 ◽

2019 ◽

Vol 32 ◽

pp. 97-99

Author(s):

Andrey Vasilyev

Keyword(s):

Mathematical Description ◽

Sound Pressure ◽

Environmental Temperature ◽

Point Of View ◽

Road Surface ◽

Vehicle Engine ◽

Movement Characteristics ◽

Surface Climate ◽

Vehicle Movement ◽

Good Coincidence

Vehicles noise is a serious problem as from the point of view of impact to environment as due to the damage of vehicle's driver and passengers health. Usually in high vehicle's speed tires noise is the most significant noise source. Mathematical description of the process of sound generation from the moving source is described. Program provision for calculation of noise generation by the system "vehicle's tires – road surface" have been developed. Software is allowing to determine sound pressure level generated by vehicle's tires during vehicle movement taking to account the following factors: - velocity of vehicle movement; - characteristics of road surface; - climate characteristics (environmental temperature, rain, snow etc.); - construction characteristics of vehicle's tires; - dimensions and mass of vehicle; - engine capacity etc. Experimental data showed good coincidence with results of calculations by using of program provision.

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A Methodology for Evaluating Driving Styles in Various Road Conditions

Energies ◽

10.3390/en14123570 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3570

Author(s):

Rafał S. Jurecki ◽

Tomasz L. Stańczyk

Keyword(s):

Detailed Analysis ◽

Urban Traffic ◽

Lateral Acceleration ◽

Urban Road ◽

The Road ◽

Road Type ◽

Movement Parameters ◽

The Impact ◽

The Given ◽

Vehicle Movement

For many institutions, it is important to evaluate a given driving technique as safe or unsafe based on measurable vehicle movement parameters. The paper constitutes a part of studies aimed at establishing a method of parameter-based evaluation of drivers in various road conditions, in other words, to create a so-called ‘driver profile’. The tests were carried out on a 650 km route, on four varying road types. Longitudinal and lateral acceleration values are used to evaluate the driving style. An analysis is presented of the impact of the type and shape of road on acceleration values. The results demonstrate that the same driver, when driving the same vehicle on an expressway, an inter-urban road or in urban traffic, will move with various acceleration values. A detailed analysis of acceleration values and distributions was conducted. Interesting conclusions were drawn after excluding the so-called ‘smooth driving’ sections, by acceleration ranges of −0.5 to 0.5 m/s2 from the analysis. This allowed for the evaluation of the structure of other longitudinal and lateral acceleration values. After this modification, the distributions showed specificity for the given road type, thereby allowing the road type used by the vehicle’s driver to be recognized based solely on the distribution.

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A Study of Coordinated Vehicle Traction Control System Based on Optimal Slip Ratio Algorithm

Mathematical Problems in Engineering ◽

10.1155/2016/3413624 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Gang Liu ◽

LiQiang Jin

Keyword(s):

Control System ◽

Control Strategy ◽

Control Method ◽

Road Surface ◽

Vehicle Model ◽

Slip Ratio ◽

Traction Control ◽

Traction Control System ◽

Optimal Slip Ratio ◽

Vehicle Acceleration

Under complicated situations, such as the low slippery road surface and split-μroad surface, traction control system is the key issue to improve the performance of vehicle acceleration and stability. In this paper, a novel control strategy with engine controller and active pressure controller is presented. First and foremost, an ideal vehicle model is proposed for simulation; then a method for the calculation of optimal slip ratio is also brought. Finally, the scheme of control method with engine controller and active brake controller is presented. From the results of simulation and road tests, it can be concluded that the acceleration performance and stability of a vehicle equipped with traction control system (TCS) can be improved.

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Influence of ride motions on the handling behaviour of a passenger vehicle

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/095440705x34702 ◽

2005 ◽

Vol 219 (9) ◽

pp. 1047-1058 ◽

Cited By ~ 10

Author(s):

B Mashadi ◽

D A Crolla

Keyword(s):

Lateral Force ◽

The Body ◽

Road Surface ◽

Lateral Acceleration ◽

Steering Wheel ◽

Slip Angle ◽

Vehicle Model ◽

Body Side ◽

Road Profile ◽

Road Surfaces

A vehicle model was developed for the investigation of the influence of ride motions on handling dynamics of passenger vehicles. The inputs to the vehicle model are the steering wheel angle and a road profile at each wheel. The outputs were first compared with the results of independent handling and ride models, and good agreement was shown to exist. The combined motion of the vehicle was investigated by the application of step steering wheel angle inputs while travelling on a rough road surface. It was seen that the cornering ability at low and moderate levels of lateral acceleration on the roads with moderate roughness was similar to that on the smooth road, but larger body side-slip angles and tyre slip angles occurred over the rough road surfaces for similar steering inputs. The maximum achievable lateral acceleration was reduced on roads with moderate roughness owing to the earlier saturation of tyre slip angles compared with those on smooth roads. Over very rough roads and at high lateral accelerations, because of the large fluctuations of normal loads and the rapid drop in available lateral force, the body side-slip angle dramatically increased, which led to instability characterized by the oversteering behaviour. At high lateral accelerations close to the limit, the vehicle that understeered over the smooth road surface exhibited oversteering behaviour over rough road surfaces.

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Investigation of Vehicle Stability with Consideration of Suspension Performance

Applied Sciences ◽

10.3390/app11209778 ◽

2021 ◽

Vol 11 (20) ◽

pp. 9778

Author(s):

Vaidas Lukoševičius ◽

Rolandas Makaras ◽

Arūnas Rutka ◽

Robertas Keršys ◽

Andrius Dargužis ◽

...

Keyword(s):

Road Surface ◽

Vehicle Body ◽

Vehicle Suspension ◽

Original Structure ◽

Vehicle Stability ◽

Main Task ◽

The Road ◽

Movement Stability ◽

On The Road ◽

Vehicle Movement

The issue of movement stability remains highly relevant considering increasing vehicle speeds. The evaluation of vehicle stability parameters and the modeling of specific movement modes is a complex task, as no universal evaluation criteria have been established. The main task in modeling car stability is an integrated assessment of the vehicle’s road interactions and identification of relationships. The main system affecting the vehicle’s road interaction is the suspension of the vehicle. Vehicle suspension is required to provide constant wheel to road surface contact, thus creating the preconditions for stability of vehicle movement. At the same time, it must provide the maximum possible body insulation against the effect of unevennesses on the road surface. Combining the two marginal prerequisites is challenging, and the issue has not been definitively solved to this day. Inaccurate alignment of the suspension and damping characteristics of the vehicle suspension impairs the stability of the vehicle, and passengers feel discomfort due to increased vibrations of the vehicle body. As a result, the driving speed is artificially restricted, the durability of the vehicle body is reduced, and the transported cargo is affected. In the study, analytical computational and experimental research methods were used. Specialized vehicle-road interaction assessment programs were developed for theoretical investigation. The methodology developed for assessing vehicle movement stability may be used for the following purposes: design and improvement of vehicle suspension and other mechanisms that determine vehicle stability; analysis of road spans assigned with characteristic vehicle movement settings; road accident situation analysis; design of road structures and establishment of certain operational restrictions on the road structures. A vehicle suspension test bench that included original structure mechanisms that simulate the effect of the road surface was designed and manufactured to test the results of theoretical calculations describing the work of the vehicle suspension and to study various suspension parameters. Experimental investigations were carried out by examining the vibrations of vehicle suspension elements caused by unevenness on the road surface.

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Investigation on Emergency Brake Property of a Heavy-Duty Vehicle Based on Functional Virtual Prototyping Model

The Open Mechanical Engineering Journal ◽

10.2174/1874155x01408010675 ◽

2014 ◽

Vol 8 (1) ◽

pp. 675-681

Author(s):

Shaohua Li ◽

Jiangbo Chen ◽

Hongwei Huang

Keyword(s):

Surface Roughness ◽

Ride Comfort ◽

Virtual Prototyping ◽

Frictional Coefficient ◽

Front Wheel ◽

Road Surface ◽

Lateral Acceleration ◽

Heavy Duty ◽

Full Vehicle ◽

Road Surface Roughness

A Functional Virtual Prototyping full vehicle model for a tri-axial heavy-duty truck is built, and the non-linearity of suspension dampers and tires is also considered. With the trajectory of full vehicle gravity center, longitudinal tire force of front wheel, longitudinal acceleration, lateral acceleration, yaw rate and pitch angle as the evaluation indexes of brake property, the influences of system parameters including wheelbase, load shift, road surface roughness and separated road friction coefficient on brake efficiency, stability and ride comfort are analyzed. In addition, the interaction of brake and full vehicle dynamics is studied. Results show that small wheelbase and load shift may improve the brake efficiency of vehicles, small road surface roughness is beneficial to brake stability and ride comfort, and great frictional coefficient difference of separation road will worsen the brake efficiency and stability.

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