A Method to Estimate the Friction Coefficient and Tire Slip Angle Using Steering Torque

2006 ◽  
Author(s):  
Yung-Hsiang J. Hsu ◽  
Shad Laws ◽  
Christopher D. Gadda ◽  
J. Christian Gerdes
Keyword(s):  
Friction Coefficient ◽  
Nonlinear Observer ◽  
Slip Angle ◽  
Power Steering ◽  
Passenger Safety ◽  
Torque Measurements ◽  
Steer By Wire ◽  
The Coefficient Of Friction ◽  
Tire Forces ◽  
Steering Torque

Knowledge of tire forces is important for vehicle control systems that aim to enhance vehicle handling and passenger safety. This paper introduces a nonlinear observer that estimates the coefficient of friction and tire slip angle, both of which are key factors in characterizing the vehicle's lateral tire forces. The observer estimates the friction coefficient and slip angle based on sensor measurements available on many production vehicles. This includes steering torque measurements readily available in steer-by-wire or electric power steering (EPS) systems. Experimental results on a steer-by-wire research vehicle (Fig. 1) demonstrate the observer's ability to provide accurate estimates out to the limits of handling.

Wireless Piezoelectric Sensor for the Measurement of Tire Deformations and the Estimation of Slip Angle

2009 ◽  
Author(s):  
Gurkan Erdogan ◽  
Lee Alexander ◽  
Rajesh Rajamani
Keyword(s):  
Friction Coefficient ◽  
Piezoelectric Sensor ◽  
Slip Angle ◽  
Lateral Deformation ◽  
Test Rig ◽  
Slip Ratio ◽  
Lateral Deflection ◽  
Road Friction ◽  
Tire Forces ◽  
Road Friction Coefficient

This paper introduces a wireless piezoelectric tire sensor whose readings can be utilized for the estimation of various tire variables such as slip angle, slip ratio, tire forces and tire road friction coefficient. In this paper, the proposed sensor is demonstrated for the estimation of tire slip angle. Lateral deformation of the tire is decoupled from radial and longitudinal tire deformations using a special sensor design. The decoupled lateral deflection profile of the tire is employed to estimate the slip angle. A new tire test rig is constructed to experimentally evaluate the performance of the developed sensor. Results show that the tire sensor can accurately estimate slip angles up to values of 5.0 degrees.

Development of a driving assist system for ultra-compact electric vehicles using a steer-by-wire system: Fundamental consideration of muscle burden and evaluation by a continuous steering operation

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1111-1118
Author(s):  
Daigo Uchino ◽  
Xiaojun Liu ◽  
Hideaki Kato ◽  
Takayoshi Narita
Keyword(s):  
Electric Vehicles ◽  
Gear Ratio ◽  
Steering Wheel ◽  
Steering Angle ◽  
Power Steering ◽  
Steer By Wire ◽  
Steering Torque ◽  
Distance Travel ◽  
Wire System ◽  
Fundamental Consideration

Ultra-compact electric vehicles has excellent environmental performance and are extremely convenient for short-distance travel. However, owing to cabin space limitations, it is difficult to mount power steering. Therefore, there is a need to increase the gear ratio of the rack and pinion to change steering angle because such vehicles need light torque to steer. However, increasing the gear ratio requires more rotations of the steering wheel. Our research group focused on developing a steer-by-wire system (SBWS) that freely controls the steering torque. Although we evaluated the burden when a driver rotates the steering wheel in one direction in a previous study. This study assumed the actual steering operation in an SBWS. And then we evaluate muscle burden when a driver steers with continuous changing of the steering direction.

An Adaptive Vehicle Stability Control Strategy Using Tire Slip-Angle Feedback

2014 ◽  
Author(s):  
Mustafa Ali Arat ◽  
Saied Taheri
Keyword(s):  
Control Strategy ◽  
Estimation Algorithm ◽  
Stability Control ◽  
Nonlinear Observer ◽  
Slip Angle ◽  
Vehicle Stability ◽  
Vehicle Performance ◽  
Contact Patch ◽  
Active Safety Systems ◽  
Tire Forces

The dynamics at the tire road contact have an immense effect on the vehicle’s handling and stability characteristics as the majority of the forces and moments acting on the vehicle chassis are generated at the tire contact patch. Sudden changes at this contact patch results in abrupt variations in vehicle characteristics which may lead to lose of control for the inexperienced driver. The active safety systems available today seek to prevent such unintended vehicle behavior by assisting drivers in maintaining control of their vehicles. Nevertheless, the lack of knowledge about the tire-road interactions highly limits their effectiveness. Motivated by this opportunity and necessity in the field, this study develops a tire slip-angle estimation algorithm and an adaptive control strategy to improve vehicle stability. The estimator uses a sensor fusion approach that integrates feedback from a concept technology, namely the intelligent tire with a model based nonlinear observer to provide information on tire forces and slip-angle. The proposed control and observer algorithms are evaluated using numerical analysis under a double lane change maneuver. To get a better measure of possible improvements in vehicle performance, the tests are executed together with baseline algorithm inspired by a conventional system. The results demonstrate that the proposed algorithms can successfully negotiate the given tasks as well as promising considerable improvements over the baseline system.

Lateral Tire Forces on Wet Roads

1977 ◽  
Vol 5 (2) ◽  
pp. 75-82 ◽  
Author(s):  
A. Schallamach
Keyword(s):  
Normal Load ◽  
The Self ◽  
Experimental Results ◽  
Slip Angle ◽  
Tire Model ◽  
Side Force ◽  
Tire Forces

Abstract Expressions are derived for side force and self-aligning torque of a simple tire model on wet roads with velocity-dependent friction. The results agree qualitatively with experimental results at moderate speeds. In particular, the theory correctly predicts that the self-aligning torque can become negative under easily realizable circumstances. The slip angle at which the torque reverses sign should increase with the normal load.

scholarly journals The Effect of Co-Deposition of SiC Sub-Micron Particles and Heat Treatment on Wear Behaviour of Ni–P Coatings

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 180
Author(s):  
Donya Ahmadkhaniha ◽  
Lucia Lattanzi ◽  
Fabio Bonora ◽  
Annalisa Fortini ◽  
Mattia Merlin ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Friction Coefficient ◽  
Wear Mechanisms ◽  
Composite Coatings ◽  
Wear Behaviour ◽  
Maximum Hardness ◽  
Sic Particles ◽  
Heat Treated ◽  
The Coefficient Of Friction ◽  
The Difference

The purpose of the study is to assess the influence of SiC particles and heat treatment on the wear behaviour of Ni–P coatings when in contact with a 100Cr6 steel. Addition of reinforcing particles and heat treatment are two common methods to increase Ni–P hardness. Ball-on-disc wear tests coupled with SEM investigations were used to compare as-plated and heat-treated coatings, both pure and composite ones, and to evaluate the wear mechanisms. In the as-plated coatings, the presence of SiC particles determined higher friction coefficient and wear rate than the pure Ni–P coatings, despite the limited increase in hardness, of about 15%. The effect of SiC particles was shown in combination with heat treatment. The maximum hardness in pure Ni–P coating was achieved by heating at 400 °C for 1 h while for composite coatings heating for 2 h at 360 °C was sufficient to obtain the maximum hardness. The difference between the friction coefficient of composite and pure coatings was disclosed by heating at 300 °C for 2 h. In other cases, the coefficient of friction (COF) stabilised at similar values. The wear mechanisms involved were mainly abrasion and tribo-oxidation, with the formation of lubricant Fe oxides produced at the counterpart.

Experimental study on the relationship between the friction coefficient and interference in locomotive axle press-fitting

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ting Wang ◽  
Hanfei Guo ◽  
Jianjun Qiao ◽  
Xiaoxue Liu ◽  
Zhixin Fan
Keyword(s):  
Friction Coefficient ◽  
Coefficient Of Friction ◽  
Friction Pair ◽  
Rolling Stock ◽  
Content Type ◽  
Press Fitting ◽  
The Press ◽  
The Coefficient Of Friction ◽  
The Relationship ◽  
Locomotive Wheels

PurposeTo address the lack of data in this field and determine the relationship between the coefficient of friction and the interference between locomotive wheels and axles, this study evaluates the theoretical relationship between the coefficient of friction and the interference under elastic deformation.Design/methodology/approachWhen using numerical analyses to study the mechanical state of the contacting components of the wheels and axle, the interference between the axle parts and the coefficient of friction between the axle parts are two important influencing factors. Currently, as the range of the coefficient of friction between the wheel and axle in interference remains unknown, it is generally considered that the coefficient of friction is only related to the materials of the friction pair; the relationship between the interference and the coefficient of friction is often neglected.FindingsA total of 520 press-fitting experiments were conducted for 130 sets of wheels and axles of the HXD2 locomotive with 4 types of interferences, in order to obtain the relationship between the coefficient of friction between the locomotive wheel and axle and the amount of interference. These results are expected to serve as a reference for selecting the coefficient of friction when designing axle structures with the rolling stock, research on the press-fitting process and evaluations of the fatigue life.Originality/valueThe study provides a basis for the selection of friction coefficient and interference amount in the design of locomotive wheels and axles.

Estimation of Tire Slip Angle and Friction Limits Using Steering Torque

2010 ◽  
Vol 18 (4) ◽  
pp. 896-907 ◽  
Author(s):  
Yung-Hsiang Judy Hsu ◽  
Shad M. Laws ◽  
J. Christian Gerdes
Keyword(s):  
Slip Angle ◽  
Steering Torque

INFLUENCE OF NITROGEN FLOW RATE ON FRICTION COEFFICIENT AND SURFACE ROUGHNESS OF TiN COATINGS DEPOSITED ON TOOL STEEL USING ARC METHOD

2007 ◽  
Vol 14 (05) ◽  
pp. 1007-1013 ◽  
Author(s):  
ESAH HAMZAH ◽  
ALI OURDJINI ◽  
MUBARAK ALI ◽  
PARVEZ AKHTER ◽  
MOHD RADZI HJ. MOHD TOFF ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Friction Coefficient ◽  
Tool Steel ◽  
Flow Rate ◽  
Physical Vapor Deposition ◽  
Gas Flow ◽  
Cutting Tools ◽  
Gas Flow Rate ◽  
Pin On Disc ◽  
The Coefficient Of Friction

In the present study, the effect of various N 2 gas flow rates on friction coefficient and surface roughness of TiN -coated D2 tool steel was examined by a commercially available cathodic arc physical vapor deposition (CAPVD) technique. A Pin-on-Disc test was carried out to study the Coefficient of friction (COF) versus sliding distance. A surface roughness tester measured the surface roughness parameters. The minimum values for the COF and surface roughness were recorded at a N 2 gas flow rate of 200 sccm. The increase in the COF and surface roughness at a N 2 gas flow rate of 100 sccm was mainly attributed to an increase in both size and number of titanium particles, whereas the increase at 300 sccm was attributed to a larger number of growth defects generated during the coating process. These ideas make it possible to optimize the coating properties as a function of N 2 gas flow rate for specific applications, e.g. cutting tools for automobiles, aircraft, and various mechanical parts.

scholarly journals Thermomechanical Couplings in Aircraft Tire Rolling/Sliding Modeling

2011 ◽  
Vol 274 ◽  
pp. 81-90 ◽  
Author(s):  
Ange Kongo Kondé ◽  
Iulian Rosu ◽  
F. Lebon ◽  
L. Seguin ◽  
Olivier Brardo ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Thermal Effects ◽  
Coulomb Friction ◽  
Large Deformations ◽  
Element Model ◽  
Slip Angle ◽  
Tire Model ◽  
Vertical Load ◽  
Coulomb Friction Law ◽  
Lateral Friction

This paper presents a finite element model for the simulation of aircraft tire rolling. Large deformations, material incompressibility, heterogeneities of the material, unilateral contact with Coulomb friction law are taken into account. The numerical model will allow estimating the forces in the contact patch - even in critical and extreme conditions for the aircraft safety and security. We show the influence of loading parameters (vertical load, velocity, inflating pressure) and slip angle on the Self Aligning torque and on the lateral friction coefficient. A friction coefficient law corresponding to Chichinadze model is considered to take into account thermal effects in the aircraft tire model behaviour.

Sign in / Sign up

Export Citation Format

Share Document