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Hjort, M., Bruzelius, F., Kharrazi, S. & Yang, D. (2024). A Method for Obtaining Reference Friction Values for Validation of Road Friction Estimation Algorithms. In: Giampiero Mastinu; Francesco Braghin; Federico Cheli; Matteo Corno; Sergio M. Savaresi (Ed.), 16th International Symposium on Advanced Vehicle Control: Proceedings of AVEC’24 – Society of Automotive Engineers of Japan. Paper presented at 16th International Symposium on Advanced Vehicle Control - AVEC 2024, Milan, Italy, September 2-6, 2024. (pp. 50-56). Springer
Open this publication in new window or tab >>A Method for Obtaining Reference Friction Values for Validation of Road Friction Estimation Algorithms
2024 (English)In: 16th International Symposium on Advanced Vehicle Control: Proceedings of AVEC’24 – Society of Automotive Engineers of Japan / [ed] Giampiero Mastinu; Francesco Braghin; Federico Cheli; Matteo Corno; Sergio M. Savaresi, Springer, 2024, p. 50-56Conference paper, Published paper (Refereed)
Abstract [en]

Data-driven development of friction estimators for passenger vehicles is becoming popular. They rely mainly on training data to obtain an accurate estimate of the current road conditions. However, reference or training data for natural conditions containing available friction is sparse. This limits the development of data-driven approaches for friction estimation. The current paper presents progress in a project devoted to developing a method to use standard equipment for road monitoring to acquire reference data for friction estimation, relevant to specific tyres and operating conditions. Results show how a mapping between existing test equipment readings and the real experienced coefficient of friction of a car tyre can be made. 

Place, publisher, year, edition, pages
Springer, 2024
Series
Lecture Notes in Mechanical Engineering (LNME), ISSN 2195-4356, E-ISSN 2195-4364
Keywords
Tyre-to-road friction, friction measurement, friction reference value
National Category
Vehicle and Aerospace Engineering
Identifiers
urn:nbn:se:vti:diva-21253 (URN)10.1007/978-3-031-70392-8_8 (DOI)2-s2.0-85206463470 (Scopus ID)9783031703911 (ISBN)9783031703928 (ISBN)
Conference
16th International Symposium on Advanced Vehicle Control - AVEC 2024, Milan, Italy, September 2-6, 2024.
Funder
Vinnova, 2020-02910
Available from: 2024-10-25 Created: 2024-10-25 Last updated: 2025-02-14Bibliographically approved
Hjort, M., Bruzelius, F., Kharrazi, S. & Ydenius, A. (2024). All-Season Tires–Investigation of Braking Performance in Summer and Winter Conditions. In: Wei Huang; Mehdi Ahmadian (Ed.), Advances in Dynamics of Vehicles on Roads and Tracks III: Proceedings of the 28th Symposium of the International Association of Vehicle System Dynamics, IAVSD 2023, August 21–25, 2023, Ottawa, Canada - Volume 2: Road Vehicles. Paper presented at 28th IAVSD Symposium on Dynamics of Vehicles on Roads and Tracks, Ottawa, Canada, August 21-25, 2023. (pp. 907-916). Springer, 2
Open this publication in new window or tab >>All-Season Tires–Investigation of Braking Performance in Summer and Winter Conditions
2024 (English)In: Advances in Dynamics of Vehicles on Roads and Tracks III: Proceedings of the 28th Symposium of the International Association of Vehicle System Dynamics, IAVSD 2023, August 21–25, 2023, Ottawa, Canada - Volume 2: Road Vehicles / [ed] Wei Huang; Mehdi Ahmadian, Springer, 2024, Vol. 2, p. 907-916Conference paper, Published paper (Refereed)
Abstract [en]

All-season tires have previously not been allowed to use in Sweden during winter. However, after a recent change of regulations they are now valid as winter tires if they are marked with the 3PMSF symbol, indicating that the tire has passed a standardized snow grip test. Whether the compromise between summer and winter grip makes them unsuitable for Swedish road conditions is an open question. The purpose of this study was to test the road grip of all-season tires during winter and summer conditions and compare them to regular winter and summer tires. A total of 14 all-season tires were carefully selected, together with a few studless winter tires and summer tires. Braking tests were performed on ice and snow tracks, as well as on dry and wet asphalt. It is clear from the results that the performance spread is very large among the tested all-season tires, where some manufacturers aim for grip on asphalt and others on snow. In general, the snow grip is worse than traditional winter tires of both Nordic and central European type, and especially so for the three all-season tires that were not 3PMSF marked. The ice grip of all-season tires was without exception much worse than what has been seen before in similar winter tires tests performed by VTI, and one of the all-season tires performed equally badly as one of the summer tires. Correlations between rolling resistance and grip on the different surface conditions were investigated as well.

Place, publisher, year, edition, pages
Springer, 2024
Series
Lecture Notes in Mechanical Engineering, ISSN 2195-4356, E-ISSN 2195-4364
National Category
Vehicle and Aerospace Engineering
Identifiers
urn:nbn:se:vti:diva-21271 (URN)10.1007/978-3-031-66968-2_89 (DOI)2-s2.0-85207644445 (Scopus ID)9783031669675 (ISBN)9783031669682 (ISBN)
Conference
28th IAVSD Symposium on Dynamics of Vehicles on Roads and Tracks, Ottawa, Canada, August 21-25, 2023.
Available from: 2024-10-28 Created: 2024-10-28 Last updated: 2025-02-14Bibliographically approved
Suo, Y., Lu, D., Bruzelius, F., Zhang, Y. & Hjort, M. (2024). Research on Prediction of Tire Camber-Sideslip Combined Mechanical Characteristics. In: Wei Huang; Mehdi Ahmadian (Ed.), Advances in Dynamics of Vehicles on Roads and Tracks III: Proceedings of the 28th Symposium of the International Association of Vehicle System Dynamics, IAVSD 2023, August 21–25, 2023, Ottawa, Canada - Volume 2: Road Vehicles. Paper presented at 28th IAVSD Symposium on Dynamics of Vehicles on Roads and Tracks, Ottawa, Canada, August 21-25, 2023. (pp. 195-208). Springer, 2
Open this publication in new window or tab >>Research on Prediction of Tire Camber-Sideslip Combined Mechanical Characteristics
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2024 (English)In: Advances in Dynamics of Vehicles on Roads and Tracks III: Proceedings of the 28th Symposium of the International Association of Vehicle System Dynamics, IAVSD 2023, August 21–25, 2023, Ottawa, Canada - Volume 2: Road Vehicles / [ed] Wei Huang; Mehdi Ahmadian, Springer, 2024, Vol. 2, p. 195-208Conference paper, Published paper (Refereed)
Abstract [en]

This article presents a new method to help achieving the rapid response of tire virtual optimization–predicting the camber-sideslip combined mechanical characteristics based on pure camber and pure sideslip. First, the influence mechanism of camber on sideslip is explored. Using the method of combining test and simulation, a finite element (FE) model of 235/55R18 tire is established, and the influence law of camber on sideslip is summarized. Secondly, the prediction method is studied. The linear region prediction is based on the load transferring along tire width caused by camber. The transition zone mechanical characteristics is predicted by treating camber as a function of load and the friction prediction considers local carcass camber (LLC) function. Finally, the application verifications of the prediction method in Magic Formula (MF) and UniTire are carried out. The prediction results are compared with the Similarity result and the MF identification result.

Place, publisher, year, edition, pages
Springer, 2024
Series
Lecture Notes in Mechanical Engineering, ISSN 2195-4356, E-ISSN 2195-4364
National Category
Vehicle and Aerospace Engineering Applied Mechanics
Identifiers
urn:nbn:se:vti:diva-21286 (URN)10.1007/978-3-031-66968-2_20 (DOI)2-s2.0-85207660456 (Scopus ID)9783031669675 (ISBN)9783031669682 (ISBN)
Conference
28th IAVSD Symposium on Dynamics of Vehicles on Roads and Tracks, Ottawa, Canada, August 21-25, 2023.
Available from: 2024-10-29 Created: 2024-10-29 Last updated: 2025-02-14Bibliographically approved
Romano, L., Timpone, F., Bruzelius, F. & Jacobson, B. (2024). Transient Tire Slip Losses Using the Brush Theory. Tire Science And Technology, 52(1), 51-75
Open this publication in new window or tab >>Transient Tire Slip Losses Using the Brush Theory
2024 (English)In: Tire Science And Technology, ISSN 0090-8657, Vol. 52, no 1, p. 51-75Article in journal (Refereed) Published
Abstract [en]

Tire slip losses have been shown to have a significant impact on vehicle performance in terms of energy efficiency, thus requiring accurate studies. In this paper, the transient dissipation mechanisms connected to the presence of micro-sliding phenomena occurring at the tire–road interface are investigated analytically. The influence of a two-dimensional velocity field inside the contact patch is also considered in light of the new brush theory recently developed by the authors. Theoretical results align with findings already known from literature but suggest that the camber and turn spins contribute differently to the slip losses and should be regarded as separate entities when the camber angle is sufficiently large. The present work shows that an additional amount of power which relates to the initial sliding conditions is generated or lost during the unsteady-state maneuvers. A simple example is presented to illustrate the discrepancy between the microscopic and macroscopic approaches during a transient maneuver.

Place, publisher, year, edition, pages
The Tire Society, 2024
Keywords
Brush model, tire models, transient tire dynamics, energy losses, slip losses
National Category
Vehicle and Aerospace Engineering Applied Mechanics
Identifiers
urn:nbn:se:vti:diva-20920 (URN)10.2346/tire.22.20002 (DOI)001197112000002 ()
Projects
COVER – Bedömning av CO2 och energieffektivitet hos fordon i verklig användning (44929-1)
Funder
Swedish Energy AgencyVinnova
Available from: 2024-05-08 Created: 2024-05-08 Last updated: 2025-02-14Bibliographically approved
Sharifzadeh, M., Bruzelius, F., Jacobson, B., Henderson, L. & Timpone, F. (2023). An effective tyre to road friction estimation applied to heavy vehicles. Proceedings of the Institution of mechanical engineers. Part D, journal of automobile engineering, 237(14), 3547-3558
Open this publication in new window or tab >>An effective tyre to road friction estimation applied to heavy vehicles
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2023 (English)In: Proceedings of the Institution of mechanical engineers. Part D, journal of automobile engineering, ISSN 0954-4070, E-ISSN 2041-2991, Vol. 237, no 14, p. 3547-3558Article in journal (Refereed) Published
Abstract [en]

Knowledge about the tyre to road friction is central to many vehicle functions as well as the overall performance of the vehicle. In this paper, a new real-time algorithm is presented for estimating the coefficient of friction using available on-board sensor information. A computationally efficient algorithm is presented, that reduces resources usage compared to previously published approaches. Issues connected to heavy vehicles and friction estimation is addressed, such as wind up of hub assembly and vehicle speed sensing. The performance of the algorithm is illustrated on data sets acquired from the test track recordings in winter conditions.

Place, publisher, year, edition, pages
Sage Publications, 2023
Keywords
Real-time estimation, friction force observer, longitudinal vehicle dynamics, chip shortage
National Category
Vehicle and Aerospace Engineering
Identifiers
urn:nbn:se:vti:diva-19508 (URN)10.1177/09544070221134197 (DOI)000891221000001 ()2-s2.0-85143211446 (Scopus ID)
Funder
Vinnova, 2016-02538
Available from: 2023-02-13 Created: 2023-02-13 Last updated: 2025-02-14Bibliographically approved
Hjort, M., Bruzelius, F., Kharrazi, S. & Ydenius, A. (2023). Test av åretruntdäck: Väggrepp på is och snö samt barmark. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>Test av åretruntdäck: Väggrepp på is och snö samt barmark
2023 (Swedish)Report (Other academic)
Alternative title[en]
Test of all-season tyres : Grip on ice, snow and asphalt
Abstract [sv]

Åretruntdäck är en typ av däck som tidigare inte varit godkända att använda som vinterdäck i Sverige, men som efter en regeländring 2019 nu är tillåtna. I syfte att jämföra väggreppet för denna typ av däck med renodlade vinter- och sommardäck så genomfördes bromstester för 14 olika åretruntdäck på packad snö och is, likväl som på torr och våt asfalt. Åretruntdäcken valdes ut för att vara representativa för de tillgängliga åretruntdäcken på den svenska marknaden, och jämförelsedäcken valdes ut för att vara representativa för respektive däcktyp. Resultaten visar att det är stora skillnader i bromsgrepp mellan olika åretruntdäck. En del åretruntdäck presterar mer likt europeiska dubbfria vinterdäck, och andra mer likt sommardäck, vilket verkar vara ett medvetet val från de olika tillverkarna. I genomsnitt så är åretruntdäckens bromssträcka på snötydligt längre än för både nordiska och europeiska dubbfria vinterdäck, och även om det finns åretruntdäck som är mer lika europeiska vinterdäck på snö, så finns det andra som är betydligt sämre. På is så är bromsgreppet för åretruntdäcken mycket sämre jämfört med det nordiska dubbfria referensdäcket.

Vår bedömning är att isgreppet överlag är för dåligt för att utgöra ett trafiksäkert alternativ på svenska vintervägar, och att ett av de vintergodkända åretruntdäcken presterade likvärdigt med ett av sommardäcken på is är anmärkningsvärt. Det finns en korrelation mellan lågt klassat rullmotstånd och dåligt isgrepp, vilket indikerar att åtgärder för att minska rullmotståndet kan vara negativt för isgreppet för denna typ av däck. Bromsprestanda på torr och våt asfalt för åretruntdäcken är generellt något bättre än de europeiska vinterdäcken, men tydligt sämre än sommardäck. Spridningen var dock stor där de bästa åretruntdäcken presterade likvärdigt med sommardäcken, och de sämsta var ungefär samma nivå som det bästa av de nordiska dubbfria vinterdäcken. Vi kan därför inte rekommendera åretruntdäck som ett alternativ till vinter- och sommardäck.

 

Abstract [en]

All-season tyres have previously not been approved for use as winter tyres in Sweden but are now allowed after a change of regulations in 2019. To compare the grip of this type of tyre with regular winter and summer tires, brake tests were conducted for 14 different all-season tyres on packed snow and ice, as well as on dry and wet asphalt. The tyres were selected to be representative of the available all-season tyres on the Swedish market. The results show large differences in braking grip between different all-season tires. Some tyres perform more like European non-studded winter tyres, and others more like summer tyres, which seems to be a conscious choice by the various manufacturers. On average, the braking distance of all-season tyres on snow is clearly longer than that of both Nordic and European non-studded winter tyres, and although there are all-season tyres that are similar to European winter tyres on snow, others perform significantly worse. On ice, the braking grip of all-season tyres is much worse compared to the Nordic non-studded reference tyre.

Our assessment is that the ice grip is generally too poor to constitute a safe alternative on Swedish winter roads, and that one of the winter-approved all-season tyres performed just as bad as one of the summer tyres on ice is remarkable. There is a correlation between low rolling resistance and poor ice grip, which indicates that measures to reduce rolling resistance can have a negative impact on the ice grip of this type of tyre. Braking performance on dry and wet asphalt for all-season tyres are widespread, with the best all-season tyres performing equally with summer tyres, and the worst being about the same level as the best of the Nordic winter tyres. We can therefore not recommend all-season tyres as an alternative to winter and summer tyres.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2023. p. 46
Series
VTI rapport, ISSN 0347-6030 ; 1183
National Category
Vehicle and Aerospace Engineering
Identifiers
urn:nbn:se:vti:diva-19963 (URN)
Funder
Swedish Transport Administration
Available from: 2023-10-23 Created: 2023-10-23 Last updated: 2025-02-14Bibliographically approved
Romano, L., Bruzelius, F. & Jacobson, B. (2022). An extended LuGre-brush tyre model for large camber angles and turning speeds. Vehicle System Dynamics, 61(6), 1674-1706
Open this publication in new window or tab >>An extended LuGre-brush tyre model for large camber angles and turning speeds
2022 (English)In: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159, Vol. 61, no 6, p. 1674-1706Article in journal (Refereed) Published
Abstract [en]

This paper presents a novel tyre model which combines the LuGre formulation with the exact brush theory recently developed by the authors, and which accounts for large camber angles and turning speeds. Closed-form solutions for the frictional state at the tyre-road interface are provided for the case of constant slip inputs, considering rectangular and elliptical contact patches. The steady-state tyre characteristics resulting from the proposed approach are compared to those obtained by employing the standard formulation of the LuGre-brush tyre models and the exact brush theory for large camber angles. Then, to cope with the general situation of time-varying slips and spins, two approximated lumped models are developed that describe the aggregate dynamics of the tyre forces and moment. In particular, it is found that the transient evolution of the tangential forces may be approximated by a system of two coupled ordinary differential equations (ODEs), whilst the dynamics of the self-aligning moment may be described by combining two systems of two coupled ODEs. Given its stability properties and ease of implementation, the lumped one may be effectively employed for vehicle state estimation and control purposes.

Place, publisher, year, edition, pages
Taylor & Francis, 2022
National Category
Vehicle and Aerospace Engineering
Identifiers
urn:nbn:se:vti:diva-18915 (URN)10.1080/00423114.2022.2086887 (DOI)000844731500001 ()2-s2.0-85132385756 (Scopus ID)
Available from: 2022-09-22 Created: 2022-09-22 Last updated: 2025-02-14Bibliographically approved
Romano, L., Timpone, F., Bruzelius, F. & Jacobson, B. (2022). Analytical results in transient brush tyre models: theory for large camber angles and classic solutions with limited friction. Meccanica (Milano. Print), 57(1), 165-191
Open this publication in new window or tab >>Analytical results in transient brush tyre models: theory for large camber angles and classic solutions with limited friction
2022 (English)In: Meccanica (Milano. Print), ISSN 0025-6455, E-ISSN 1572-9648, Vol. 57, no 1, p. 165-191Article in journal (Refereed) Published
Abstract [en]

This paper establishes new analytical results in the mathematical theory of brush tyre models. In the first part, the exact problem which considers large camber angles is analysed from the perspective of linear dynamical systems. Under the assumption of vanishing sliding, the most salient properties of the model are discussed with some insights on concepts as existence and uniqueness of the solution. A comparison against the classic steady-state theory suggests that the latter represents a very good approximation even in case of large camber angles. Furthermore, in respect to the classic theory, the more general situation of limited friction is explored. It is demonstrated that, in transient conditions, exact sliding solutions can be determined for all the one-dimensional problems. For the case of pure lateral slip, the investigation is conducted under the assumption of a strictly concave pressure distribution in the rolling direction.

Place, publisher, year, edition, pages
Springer, 2022
National Category
Vehicle and Aerospace Engineering
Research subject
90 Road: Vehicles and vehicle technology, 911 Road: Components of the vehicle
Identifiers
urn:nbn:se:vti:diva-18665 (URN)10.1007/s11012-021-01422-3 (DOI)
Funder
Vinnova, 44929-1Chalmers University of Technology
Available from: 2022-05-23 Created: 2022-05-23 Last updated: 2025-02-14Bibliographically approved
Romano, L., Bruzelius, F. & Jacobson, B. (2022). Brush tyre models for large camber angles and steering speeds. Vehicle System Dynamics, 60(4), 1341-1392
Open this publication in new window or tab >>Brush tyre models for large camber angles and steering speeds
2022 (English)In: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159, Vol. 60, no 4, p. 1341-1392Article in journal (Refereed) Published
Abstract [en]

In this paper, we discuss three improved brush models. The first one deals with the coupling between the slip and spin parameters and is valid for relatively high steering speed and small camber angles; the second one is more complex and considers the presence of a two-dimensional velocity field inside the contact patch due to large camber angles; the third one is more general and combines both the previous formulations. For the last two models, the investigation is conducted with respect to a rectangular contact patch, for which we show that three different regions can be identified, each of them corresponding to a different steady-state solution for the deflection of the bristle. Furthermore, from the transient analysis it emerges that each region can be in turn separated into an area in which steady-state conditions reign and another one in which the transient solution takes place. An asymptotic analysis is carried out for the three models and it is shown that the solutions are equivalent to the ones predicted by the standard brush theory for small values of the spin ratio and camber angle. Finally, a comparison is performed amongst the models to highlight the differences in the predicted tyre characteristics. © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

Place, publisher, year, edition, pages
Taylor & Francis, 2022
Keywords
brush models, nonlinear theory, transient dynamics, transport equation, two-dimensional theory, Tyre modelling
National Category
Vehicle and Aerospace Engineering Applied Mechanics
Identifiers
urn:nbn:se:vti:diva-15876 (URN)10.1080/00423114.2020.1854320 (DOI)000596306000001 ()2-s2.0-85097134604 (Scopus ID)
Funder
Swedish Energy Agency
Note

Research funding provided by the COVER project (44929-1), funded by the Swedish energy agency and the Swedish vehicle research and innovation programme (FFI).

Available from: 2020-12-29 Created: 2020-12-29 Last updated: 2025-02-14Bibliographically approved
Romano, L., Bruzelius, F., Hjort, M. & Jacobson, B. (2022). Development and analysis of the two-regime transient tyre model for combined slip. Vehicle System Dynamics, 61(4), 1028-1062
Open this publication in new window or tab >>Development and analysis of the two-regime transient tyre model for combined slip
2022 (English)In: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159, Vol. 61, no 4, p. 1028-1062Article in journal (Refereed) Published
Abstract [en]

This paper refines the two-regime transient theory developed by Romano et al. [Romano L, Bruzelius F, Jacobson B. Unsteady-state brush theory. Vehicle Syst Dyn. 2020;59:11-29. DOI: 10.1080/00423114.2020.1774625.] to include the effect of combined slip. A nonlinear system is derived that describes the non-steady generation of tyre forces and considers the coupling between the longitudinal and lateral characteristics. The proposed formulation accounts for both the carcass and the bristle dynamics, and represents a generalisation of the single contact point models. A formal analysis is conducted to investigate the effect of the tyre carcass anisotropy on the properties of the system. It is concluded that a fundamental role is played by the ratio between the longitudinal and lateral relaxation lengths. In particular, it is demonstrated that the maximum slip that guarantees (partial) adhesion conditions does not coincide with the stationary value and decreases considerably for highly anisotropic tyres. The dissipative nature of the model is also analysed using elementary tools borrowed from the classic theory for nonlinear systems. A comparison is performed against the single contact point models, showing a good agreement especially towards the full-nonlinear one. Furthermore, compared to the single contact point models, the two-regime appears to be able to better replicate the exact dynamics of the tyre forces predicted by the complete brush theory. Finally, the transient model is partially validated against experimental results.

Place, publisher, year, edition, pages
Taylor & Francis, 2022
National Category
Vehicle and Aerospace Engineering
Identifiers
urn:nbn:se:vti:diva-18567 (URN)10.1080/00423114.2022.2057335 (DOI)000778034100001 ()2-s2.0-85129199313 (Scopus ID)
Available from: 2022-12-02 Created: 2022-12-02 Last updated: 2025-02-14Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-6317-8795

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