Wyniki wyszukiwania - BazTech

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Symulacyjna ocena wpływu nabiegania ogumienia na dynamikę poprzeczną i bezpieczeństwo ruchu pojazdu podczas przejazdu przez pojedynczą nierówność podłoża w ruchu krzywoliniowym

Luty W.

Prace Naukowe Politechniki Warszawskiej. Transport

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2016

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z. 112

261--270

PL

W pracy przedstawiono możliwe przyczyny obniżenia wartości reakcji bocznej przenoszonej przez koła pojazdu w ruchu krzywoliniowym na skutek ich wprowadzenia w stan drgań pionowych. Wykonano badania symulacyjne pojazdu w warunkach ruchu krzywoliniowego podczas przejazdu po pojedynczej nierówności podłoża. Wykazano, że nabieganie ogumienia może znacznie zwiększyć poziom obciążeń dynamicznych elementów układu jezdnego pojazdu. Jednocześnie wykazano, że nabieganie ogumienia istotnie zwiększa wrażliwości pojazdu na zakłócenia ruchu krzywoliniowego wywołane przejazdem po nierówności podłoża.

EN

The paper presents the possible causes of a reduction in the value of lateral reaction force transmitted by the tire during nonlinear vehicle motion when the vehicle wheels are in state of vertical vibrations. Simulation tests of vehicle in nonlinear motion, when driving over the single unevenness of the road surface have been performed. It has been shown that the tire relaxation can significantly increase the level of dynamic loads of vehicle chassis components. At the same time it have been demonstrated that the tire relaxation can significantly increase the vehicle sensitivity to disturbances of its nonlinear motion caused by passing through the unevenness of road surface.

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Influence of the tire relaxation on the simulation results of the vehicle lateral dynamics in aspect of the vehicle driving safety

Luty W.

Journal of KONES

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2015

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Vol. 22, No. 1

185--192

EN

Selected experimental research results of truck tire in steady-state side cornering and transient cornering conditions are presented in this paper. Experimental research results of the tire have been used in simulation research of medium duty truck in nonlinear driving conditions. The paper presents the structure of the vehicle dynamics model and a description of applied tire-road interaction model. Simulation research of the vehicle lateral dynamics has been performed in two variants: without and with the model of tire relaxation. During research, the tire relaxation length has been also changed. The steering wheel angle changes were forced as continuous sinusoidal excitation signal with a constant amplitude and with continuously increasing frequency. There have been analysed basic physical quantities characterizing the vehicle lateral dynamics connected with the vehicle active safety, especially including body yaw velocity and lateral acceleration in the centre of the truck body mass. An analysis of research results have been performed in the time and frequency domain. Time courses of analysed physical quantities and their frequency spectrum, obtained for tire-road interaction model without and with the tire relaxation (with different values of relaxation length) have been compared. Based on the simulation research results there have been considered the influence of tire relaxation on the vehicle performance. There have been shown that the tire relaxation can significantly change courses of observed physical quantities connected with vehicle lateral dynamics connected with vehicle driving safety.

3

Nieustalone stany znoszenia bocznego ogumienia kół jezdnych w symulacji ruchu krzywoliniowego pojazdu

Luty W.

Prace Naukowe Politechniki Warszawskiej. Transport

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2013

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z. 98

357--367

PL

W pracy przedstawiono teoretyczny opis właściwości dynamicznych ogumienia kół jezdnych samochodu. Pokazano przykładowe charakterystyki dynamiczne koła ogumionego. Na podstawie wyników badań symulacyjnych przedstawiono wpływ nabiegania ogumienia na zmiany wybranych wielkości fizycznych, które charakteryzują dynamikę pojazdu w ruchu krzywoliniowym. Wykazano wpływ nabiegania ogumienia na wartości amplitudy oraz przesunięcie w czasie obserwowanych charakterystyk pojazdu.

EN

The paper presents a theoretical description of the dynamic properties of vehicle tired wheels. Dynamic characteristics of tired wheel have been shown. Based on the simulation results the effect of tire relaxation on changes in selected physical quantities that characterize the vehicle dynamics has been presented.

4

Wyznaczanie parametrów modelu nabiegania ogumienia na podstawie wyników badań eksperymentalnych

Luty W.

Postępy Nauki i Techniki

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2012

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Nr 14

135-147

PL

W pracy przedstawiono wyniki badań eksperymentalnych ogumienia samochodu ciężarowego w nieustalonych warunkach znoszenia bocznego koła. Pokazano sposób aproksymacji wyników badań poprzez dopasowanie modelu nabiegania do charakterystyki nabiegania koła ogumionego. Przedstawiono sposób ręcznego oraz zautomatyzowanego doboru długości drogi nabiegania, z uwzględnieniem zmiany wartości obciążenia normalnego koła oraz zadawanego kąta znoszenia. Przedstawiono uproszczoną metodę określenia parametrów nabiegania na podstawie znanej wartości sztywności bocznej opony. Metoda umożliwia wyznaczenie wartości długości drogi nabiegania i jej zastosowanie bezpośrednio w modelu współpracy koła ogumionego z podłożem, z uwzględnieniem nieustalonych stanów znoszenia bocznego.

EN

Experimental research results of truck tire in conditions of not steady-state side cornering are presented in this paper. A way of tire relaxation model approximation to the tire relaxation characteristics, obtained from experimental research have are presented. A way of manual and automated selection of relaxation length value, taking into account changes in the normal load and the wheel cornering angle are presented. A simplified method to determine relaxation parameters basing on the known value of tire lateral stiffness is described. Presented method allows to determine the relaxation length and its direct application in the model of tire-road interaction, including the tire relaxation.

5

An analysis of tire relaxation in conditions of the wheel side cornering agle oscilations

Luty W.

Journal of KONES

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2011

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Vol. 18, No. 1

325-332

EN

Results of laboratory experimental research of a truck tire, in conditions of side cornering angle dynamic changes are presented in this work. As research objects, there were 2 truck tires. These tires had different construction and as an effect they had different properties, including cornering resistance and relaxation length. Tires tests have been performed using the dynamometric trailer, fixed on the drum facility. During testing, the wheel side cornering angle oscillatory changes have been forcing, with frequency of 2 and 4Hz, in wide scope of the wheel rolling velocity. Chosen measurement results of lateral reaction force have been presented in time domain. Values of the lateral force oscillations amplitude and lateral force time lag have been observed. Amplitude and phase dynamic characteristics of tires, using FFT transformation, have been determined. A decrease of the lateral force oscillations amplitude and an increase of the lateral force phase shift with increasing input signal frequency, as the wheel cornering angle oscillations, have been shown. Conclusions about influence of the wheel rolling speed on tire relaxation effects in dynamic conditions have been formulated. There have been revealed that different properties of different tires types, described in quasistatic conditions have an influence on their behaviour also in dynamic conditions. Lower tire cornering resistance can decrease an amplitude of lateral force oscillations whilst greater tire relaxation length can decrease an amplitude and also can increase phase shift of lateral force oscillations.

6

An analysis of tire relaxation process during dynamic changes of cornering angle

Luty W.

Journal of KONES

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2009

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Vol. 16, No. 1

307-316

EN

The work presents results of laboratory experimental research of a truck tire in dynamic motion conditions. Researches were performed using dynamometric trailer and dual drum facility for tire dynamics testing. The research object was a new structure truck, tubeless tire (275/70R22.5) with steel cord included also in carcass and bell. Tested tired wheel was rolling over steel drum surface with different speed. A wheel cornering angle was forces with different increase and similar decrease rate. The control system of hydraulic wheel turning mechanism was controlled by the voltage signals generated by software, through the D/A converter card. Values of cornering angle and also lateral reaction force transmitted by tested wheel were measured during tests performing. Changes of lateral reaction force values, transmitted by a tired wheel depending on forced wheel cornering angle were observed. Tire behaviour in the conditions of wheel cornering angle variations at different wheel rolling speed is presented. An influence of tire relaxation on values of transmitted lateral reaction force, during forcing of wheel cornering angle, is presented. As a result, there are presented differences in transient tire behaviour during forcing of wheel cornering angle with different increase rate and at different wheel rolling speed. A scope of wheel motion conditions are indicated, where tire relaxation can be important in case of modelling its interaction with the ground in the aspect of vehicle driving safety and comfort. Lateral reaction force value, transmitted by a wheel, the tire relaxation phenomenon becomes less significant when the rolling speed increases, the cornering angle value increases and when the rate of the wheel cornering angle variation rate decreases. It has been also shown that the relaxation phenomenon occurs both when cornering angle increases or decreases.