System for Testing a Tire to Avoid a Torque Steer Effect

Total Page:16

File Type:pdf, Size:1020Kb

System for Testing a Tire to Avoid a Torque Steer Effect Europaisches Patentamt 0 091 393 J) European Patent Office Publication number: B1 Office europeen des brevets EUROPEAN PATENT SPECIFICATION into.4: G 01 M 17/02, G 01 B 11/08, Date of publication of patent specification: 02.11.88 G 01 P 3/60 Application number: 83630053.3 Date of filing: 05.04.83 System for testing a tire to avoid a torque steer effect. Proprietor: THE GOODYEAR TIRE & RUBBER Priority: 05.04.82 US 365593 COMPANY 1144 East Market Street Akron, Ohio 44316-0001 (US) Date of publication of application: 12.10.83 Bulletin 83/41 Inventor: Brown, Jack Edward, Jr. 936 Merriman Road Akron Ohio 44303 (US) Inventor: Dutt, William Randall Publication of the grant of the patent: 139 Hametown Road 02.1 1.88 Bulletin 88/44 Copley Ohio 44321 (US) Inventor: Glemming, David Allen 3630 Portage Point Boulevard States: Akron Ohio 44319 (US) Designated Contracting Inventor: Greenhorn, Richard James DEFRGB 2341 Lynnwood Drive Stow Ohio 44224 (US) Inventor: Heisler, Michael Guy References cited: 221 Asbury Road 089 783 Ithaca New York 14850 (US) GB-A-1 Inventor: Muhl, John Siegfried US-A-4 173 850 3311 Shellhart Road Norton Ohio 44203 (US) Inventor: Vandale, Leonard Albert 1023 Johnston Street Akron Ohio 44306 (US) co Inventor: Winslow, Douglas Lynn 41 Jalan Beka Damansara Heights Kuala Lumpur (MY) CO 0 Representative: Weyland, Joseph Jean Pierre Patent 5> Goodyear Technical Center Luxembourg Department Avenue Gordon Smith o L-7750 Colmar-Berg (LU) o Within nine months from the publication of the mention of the grant of the European patent any person may Note- of shall notice to the European Patent Office of opposition to the European patent granted. Notice opposition give until the fee has been CL be filed in a written reasoned statement. It shall not be deemed to have been filed opposit.on 111 paid. (Art. 99(1 ) European patent convention). Courier Press, Leamington Spa, England. 0 091 393 Description Background of the invention The present invention relates generally to tire testing devices and more particularly to a method of 5 testing a tire in order to reduce the torque steer effect when the tires are used with an automotive vehicle. Torque steer generally refers to an undesirable tendency of an automotive vehicle to move or turn laterally when torque, or thrust, is applied to its driven wheels. Torque is applied, for example, when the vehicle accelerates or decelerates. The torque steer effect is particularly acute in cars that are steered and driven by the same wheels. w "Front wheel drive" vehicles are normally steered and driven by the same wheels and accordingly are influenced by the torque steer effect. In recent years, the number of such cars produced has increased significantly. Overcoming the torque steer effect has thus become increasingly important. One example of a device for measuring the characteristics of a tire is disclosed in US — A — 4,173,850. This prior art patent relates to a method for measuring tangential force variations in pneumatic tires. In the 15 method disclosed in this patent, pneumatic tires are mounted on a wheel rim, inflated to an operating pressure, and rotated under a predetermined load against a loading drum. Force transducers on the axis of the loading drum measure the tangential force variation as the tire rotates. The patent, however, does not mention the measurement of the effective rolling radius of the tire as set forth below. 20 Summary of the invention In attempting to reduce the effect of torque steer. Applicant realized that torque steer could be caused by a variety of additive factors, such as plysteer or the design of the vehicle itself. Applicant also recognized that the radius of a tire could play an important part in avoiding undesired torque steer characteristics. The radius of a static, inflated tire changes as a load, or weight is placed on it. Applicant has noted, 25 however, that knowledge regarding the static, loaded radius of a tire is of only limited importance in attempting to eliminate the torque steer effect. Applicant has ascertained, however, that the radius of a tire also changes as it rotates, and particularly as it rotates under a load. This latter type of radius — the radius of a tire as it revolves under a load — is referred to as the "effective rolling" radius. It can be thought of as the radius of an imaginary, perfectly 30 round circle that has the same circumference as the tire when the tire is revolving under a load. After substantial effort, Applicant discovered that if the "effective rolling" radius of each steerable, driving wheel is kept within a close tolerance, the torque steer effect can be signifiantly reduced. Just as the radius of a tire change as it begins to revolve under a load, the rolling circumference of a tire also, of course, changes in proportion to how the rolling radius changes. The circumference of the tire 35 revolving under a load is referred to as "effective rolling" circumference. The effective rolling radius of a revolving, loaded tire cannot be accurately ascertained simply by determining the distance from the center of the tire to road surface. This is partly due to the deformation that the upper portion of the tire undergoes when it revolves under a load. The upper portion of the tire, which is not in contact with the road, tends to bulge out. As a result, the tire has a larger effective rolling 40 circumference than is suggested by the distance between the center of the tire and the roadway. Thus, the measurement of such a distance cannot accurately indicate the tire's effective rolling circumference or effective rolling radius. The present invention is characterized by the means recited in appended claim 1. It is thus an object of the present invention to substantially reduce the torque steer effect. Other objects 45 of the invention are: (1) to easily and quickly determine the effective rolling radius of a tire; (2) to conveniently measure the effective rolling circumference of a tire; (3) to allow tires to be more closely matched before they are mounted on a vehicle and thus reduce customer complaints about the torque steer effect; and 50 (4) to use a small number of components to determine the effective rolling parameters of a tire so that the invention may be readily and inexpensively manufactured. Description of the drawing These and other objects, advantages, and features of the present invention will hereafter appear in 55 connection with the accompanying drawing, wherein like numbers refer to like parts throughout and wherein: Figure 1 is a perspective view of an automotive vehicle having two front tires that have been tested in accordance with a preferred form of the present invention; Figure 2 is a schematic diagram illustrating, in exaggerated detail, the differences between an go unloaded radius, a loaded radius, and an effective radius, in order to explain the operation of a preferred form of the present invention; Figure 3 is a block diagram showing the steps in manufacturing a tire which has been tested according to the method of the present invention; Figure 4 is a partial, front elevational view of a preferred form of the present invention, showing two 65 chucks in a spaced relation; 0 091 393 Figure 5 is a partial, front elevational view of a preferred form of the present invention, showing two chucks in a closed relation and a cross section of a tire; Figure 6 is a schematic diagram illustrating the interaction of a tire and a rolling load drum in a preferred form of the present invention; 5 Figure 7 is a graph illustrating the interaction between a first detector, a second detector, and a processor in a preferred form of the present invention; Figure 8 is a short flowchart showing an overview of the program under which the microprocessor of the present invention operates; and Figure 9 is a detailed flowchart illustrating the program under which the microprocessor of the present w invention operates. Description of a preferred embodiment Referring to Figure 1, an exemplary automotive vehicle 11 having front wheel drive is shown. The automotive vehicle 1 1 includes a drive train assembly 13, a steering assembly 15, a set of front, steerable 15 wheels 17, 19 and associated tires 21, 23, and a set of rear non-steerable wheels 25, 27 and associated tires 29, 31. The drive train assembly 13 includes a power plan 33 and two shafts 35, 37, each of which is interconnected with one of the two front wheels 17, 19 (Figure 1). The two front wheels 17, 19 are thus rotatably driven and propel the vehicle 11. 20 The steering assembly 15 includes a steering wheel 39. The steering wheel 39 is connected to the two front wheels 17, 19 (Figure 1). Since the vehicle 1 1 has front wheel drive, the effect of torque steer is particularly noticeable. Thus, if the power plant 33 provides torque, or thrust, to the two front wheels 17, 19 (and the radii of the two front tires 21, 23 are not properly "matched"), the vehicle 11 will tend to move or turn laterally, even though the 25 steering wheel 39 has not been turned. Usually, under such circumstances, the vehicle 11 tends to turn toward the tire having the smaller radius. Applicants have discovered that if the two front tires 21, 23 are "matched" within certain tolerances, the effect of torque steer is substantially reduced. The "matching" process involves the determination of a particular type of radius of the tires 21, 23. 30 The profile of a fully inflated tire, standing free and unassociated with any vehicle, is defined by a dotted, circular line 41 in Figure 2a.
Recommended publications
  • Advances in Truck and Bus Safety
    EVALUATING THE NEED FOR CHANGING CURRENT REQUIREMENTS TOWARDS INCREASING THE AMOUNT OF LIGHTING DEVICES EQUIPPING SEMI TRAILERS Krzysztof Olejnik Motor Transport Institute Poland Paper No. 07 – 0135 the driven truck in relation to the unilluminated ABSTRACT objects. The similar situation takes place when The report has pointed out the need to manoeuvres are carried out in none lit up place and provide the truck driver with a semi trailer, the there are unilluminated objects either side of the ability to see the contour of the semi trailer and road vehicle. illumination in the insufficient lighting conditions. The need for equipping the vehicle with additional THE ESTIMATION OF THE SITUATION AND contour light and lamps illuminating the section of CHANGES PROPOSED. the road overrun by the semi trailer wheels has been assessed. The driver of the vehicle or group of vehicles should This is particularly important during have the possibility to observe the surroundings of manoeuvring with such truck – semi trailer unit at the vehicle together with the elements of the night to ensure safety, as the semi trailer has a contour of this vehicle – see Figure 1 [1,2]. The different tracking circle than the towing truck. drawing presented below shows these areas around Current regulations are too (categorical) restrictive the vehicle. and limiting possibility of introducing additional The driver should have the ability to observe them lights. The proposal for technically solving this during driving, both during a day and at night. It problem as well as amending the regulations, has should be possible under the street lighting and been presented.
    [Show full text]
  • C2101, C2201, C2103 & C2203
    INSTALLATION INSTRUCTIONS S/S COMPETITION TRACTION BARS P/N'S: C2101, C2201, C2103 & C2203 Competition Engineering Leaf Spring Traction Bars are designed especially for use in drag race classes that require a bolt-on traction device such as Stock Eliminator and Bracket Racing. These bars will eliminate wheel hop and improve traction by applying the force which normally produces unwanted tire spin into a downward force where the tire meets the pavement. These bars are capable of handling horsepower levels up to 450hp. They are designed with a snubber location that is positioned directly under the front spring eye bolt, eliminating spring damage and increasing the lever effect on the rear tires. NOTE: These traction bars may not work with the stock rear sway bar on some vehicle models. We recommend that you modify the bar to fit or remove it. PARTS LIST 2) Competition Traction Bars 4) 1/2" J-Bolts 2) 7/16" Square U-Bolts 2) Rubber Snubbers 8) 1/2"-20 Nuts 8) 1/2"-20 Locknuts 12) 1/2" Flat Washers 4) 7/16"-14 Locknuts 4) 7/16"-14 Nuts 2) 3/8"-16 Locknuts INSTALLATION 1) Check rear springs for broken leaves. Replace if necessary. 2) Jack up the rear of the car and place two jack stands under the frame member directly in front of the rear spring. Allow the rear housing to hang down with its weight on the springs. 3) Disconnect the shock absorber at the lower mounting point. Remove the stock lower spring plates and U-Bolts. NOTE: When replacing U-Bolts with the supplied J-Bolts, you must use either the factory T-Bolt or a 1/2" Grade 8 bolt.
    [Show full text]
  • Service Bulletin
    ATTENTION: IMPORTANT - All GENERAL MANAGER q Service Personnel PARTS MANAGER q Should Read and Initial in the boxes CLAIMS PERSONNEL q provided, right. SERVICE MANAGER q © 2019 Subaru of America, Inc. All rights reserved. SERVICE BULLETIN APPLICABILITY: 2018-19MY STI NUMBER: 04-25-19R SUBJECT: Torque Steer Diagnostics and Repair Procedure DATE: 04/25/19 REVISED: 08/28/19 INTRODUCTION: The primary focus of this bulletin is to provide a procedure to follow when diagnosing a customer concern of Torque Steer, defined as a pulling condition to either the left or right when under full acceleration which requires a somewhat greater than standard correction of steering wheel input from the driver to counteract. As part of this diagnosis, it will be necessary to first eliminate two other conditions a customer may misinterpret as torque steer. These are: Steering Pull and Steering Off-Center. This will prevent incorrect or over-repair, both of which can negatively impact customer satisfaction. This bulletin applies only in cases where the original factory equipment wheels, tires, and all suspension components are currently installed and, the outlined condition is confirmed to be present. SERVICE PROCEDURE / DIAGNOSTIC INFORMATION: Definition of Terms: • Torque Steer: A pull to either the left or right during full acceleration (high engine torque) which requires a somewhat greater than standard steering wheel input from the driver to counteract and keep the vehicle moving straight ahead. • Steering “Pull”: A tendency for the vehicle to pull or “drift” to the left or right while at speed (not under acceleration) and holding the steering wheel straight ahead.
    [Show full text]
  • Car Suspension and Handling Fourth Edition
    Car Suspension and Handling Fourth Edition List of Chapters: Preface to the Fourth Edition 3.8 Tire Uniformity 3.9 Aspect Ratios Preface to the First Edition 3.10 Tire Selection and Air Chamber Geometry Notation 3.11 References Chapter 1 Introduction Chapter 4 Steering 1.1 Scope and Layout of the Book 4.1 Dynamic Function of the Steering 1.2 The Function of the Suspension System System 4.2 Steering Angles: Effects of Tire Slip 1.3 Suspension Geometry Angles and Steering and Suspension 1.4 Kinematics and Compliance (K&C) Kinematics 1.5 Vehicle Dynamics 4.3 Relative Positions of Front- and Rear- 1.6 References Wheel Tracks 4.4 Understeer and Oversteer Chapter 2 Disturbances and Sensitivity 4.5 Directional Stability 2.1 Road Irregularities 4.6 Torque in the Steering System 2.2 Influence of Wheel Size 4.7 Steering Torque Effects Due to 2.3 Subjective Assessment of Ride Steering Geometry 2.4 Human Sensitivity to Vibration 4.8 The Steering Column 2.5 Measurement Standards for Vibration 4.9 Steering Gear 2.6 Influence of Noise on Assessment of 4.10 Constant Velocity (CV) Driveshaft Ride Comfort Joints 2.7 Influence of Phase of Differential 4.11 Torque Steer Effects Vibration on Assessment of Ride 4.12 Front-Wheel Steering Oscillations— Comfort Shimmy 2.8 References 4.13 Power Assistance 4.14 Electric Power Steering Chapter 3 The Wheel and Tire 4.15 Rear-Wheel Steering Systems 3.1 Introduction 4.16 References 3.2 The Wheel Rim 3.3 Tire Size Designation Chapter 5 Suspension Systems and 3.4 Tire Construction Types Their Effects 3.5 Tire Properties
    [Show full text]
  • The Automotive Chassis Engineering Principles List of Chapters
    The Automotive Chassis Engineering Principles List of Chapters Preface 2.2.2 Radial ply tyres 2.2.3 Tubeless or tubed 1 Types of suspension and drive 2.2.4 Height-to-width ratio 1.1 General characteristics of wheel suspensions 2.2.5 Tyre dimensions and markings 1.2 Independent wheel suspensions - general 2.2.6 Tyre load capacities and inflation 1.2.1 Requirements pressures 1.2.2 Double wishbone suspensions 2.2.7 Tyre sidewall markings 1.2.3 McPherson struts and strut dampers 1.2.4 Rear axle trailing-arm suspension 2.2.8 Rolling circumference and driving 1.2.5 Semi-trailing-arm rear axles speed 1.2.6 Multi-link suspension 2.2.9 Influence of the tyre on the 1.3 Rigid and semi-rigid crank axles speedometer 1.3.1 Rigid axles 2.3 Wheels 1.3.2 Semi rigid crank axles 2.3.1 Concepts 1.4 Front-mounted engine, rear-mounted drive 2.3.2 Rims for passenger cars, light 1.4.1 Advantages and disadvantages of commercial vehicles and trailers the front-mounted engine, rear- 2.3.3 Wheels for passenger cars, light mounted drive design commercial vehicles and trailers 1.4.2 Non-driven front axles 2.3.4 Wheel mountings 1.4.3 Driven rear axles 2.4 Springing behaviour 1.5 Rear and mid engine drive 2.5 Non-uniformity 1.6 Front-wheel drive 2.6 Rolling resistance 1.6.1 Types of design 2.6.1 Rolling resistance in straight-line 1.6.2 Advantages and disadvantages of driving front-wheel drive 2.6.2 Rolling resistance during cornering 1.6.3 Driven front axles 2.6.3 Other influencing variables 1.6.4 Non-driven rear axles 2.7 Rolling force coefficients and sliding friction
    [Show full text]
  • Hydraulic Power Steering System Design in Road-Analysis, Testing
    avhandling marro 2007/01/14 20:34phd_andjo page2005/08/17 iii 13:51 page 1 Link¨oping Studies in Science and Technology. Dissertations Linköping StudiesNo. in Science1068 and Technology. Marcus Rösth Dissertations No.1068 965 DesignHydraulic Principles Power Steering for Noise System Reduction Design in in HydraulicHydraulicRoad Power PistonVehicles Steering Pumps SystemSimulation,Analysis, Optimisation Design Testing and in andEnhanced Road Experimental Functionality Vehicles Verification Analysis, TestingarcuMarcuss andRs Enhancedth Rösth Functionality RoadVehicles Hydraulic Power Steering System Design in Marcus R¨osth Linköping 2005 Hydraulic Piston Pumps Design Principles for NoiseAndreas Reduction Johansson in Division of Fluid and Mechanical Engineering Systems Department of Mechanical Engineering Division of FluidLink and¨oping Mechanical University Engineering Systems DepartmentSE–581 83 of Link Mechanical¨oping, Sweden Engineering 2007 Linköpings universitet SE–581 83 Linköping, Sweden Link¨oping 2007 Linköping 2005 August 17, 2005 1 avhandling marro 2007/03/07 20:41 page i Hydraulic Power Steering System Design in Road Vehicles Analysis, Testing and Enhanced Functionality avhandling marro 2007/03/07 20:41 page ii avhandling marro 2007/03/07 20:41 page iii Link¨oping Studies in Science and Technology. Dissertations No. 1068 Hydraulic Power Steering System Design in Road Vehicles Analysis, Testing and Enhanced Functionality Marcus R¨osth Division of Fluid and Mechanical Engineering Systems Department of Mechanical Engineering Link¨oping University SE–581 83 Link¨oping, Sweden Link¨oping 2007 avhandling marro 2007/03/07 20:41 page iv ISBN 978-91-85643-00-4 ISSN 0345-7524 Copyright c 2006 by Marcus R¨osth Department of Mechanical Engineering Link¨oping University SE-581 83 Link¨oping, Sweden Printed in Sweden by LTAB Link¨opings Tryckeri AB, 2007.445 avhandling marro 2007/03/07 20:41 page v To my wife Jennifer M¨angden tror att allt sv˚arfattligt ¨ar djupsinnigt, men s˚a ¨ar det icke.
    [Show full text]
  • Torque Split Between Left and Right Drive Shaft Over a Front Wheel Drive Differential
    Torque split between left and right drive shaft over a front wheel drive differential Mechanical and Automotive Engineering Master’s Thesis in the Mechanical and Automotive Engineering Msc MARC OLLÉ BERNADES Department of Applied Mechanics Division of Vehicle Dynamics and Autonomous Systems Vehicle Dynamics Group CHALMERS UNIVERSITY OF TECHNOLOGY Göteborg, Sweden 2012 Master’s thesis 2012:21 MASTER’S THESIS IN VEHICLE DYNAMICS AND AUTONOMOUS SYSTEMS Torque split between left and right drive shaft over a front wheel drive differential MARC OLLÉ BERNADES Department of Applied Mechanics Vehicle Dynamics and Autonomous Systems Vehicle Dynamics Group CHALMERS UNIVERSITY OF TECHNOLOGY Göteborg, Sweden 2012 Torque split between left and right drive shaft over a front wheel drive differential MARC OLLÉ BERNADES © MARC OLLÉ BERNADES 2012 Master’s Thesis 2012:21 ISSN 1652-8557 Department of Applied Mechanics Division of Vehicle Dynamics and Autonomous Systems Vehicle Dynamics Group Chalmers University of Technology SE-412 96 Göteborg Sweden Telephone: + 46 (0)31-772 1000 Cover: There is shown a brief representation, starting from the differential design, of all the steps that are followed (Modelling, Rig design, FEM analysis, Rig Test and Dynamic simulations) during this Thesis Work. Chalmers University of Technology / Department of Applied Mechanics Göteborg, Sweden 2012 Torque split between left and right drive shaft over a front wheel drive differential Master’s Thesis in Mechanical Engineering MARC OLLÉ BERNADES Department of Applied Mechanics Division of Vehicle Dynamics and Autonomous system Chalmers University of Technology ABSTRACT Steering feel and vehicle steering motion is affected by wheel torques from propulsion, especially for front wheel drive cars.
    [Show full text]
  • Torsen LSD in Conventional and Electric Axles with EPS Tuning (Electric Power Steering)
    EAWD’19 Torsen LSD in conventional and electric axles with EPS tuning (Electric Power Steering) Presented by Paolo Sacchettini JTEKT TORSEN EUROPE 1 Torsen is a registered trademark of JTEKT Corporation PROPRIETARY JTEKT CORPORATION Torsen LSD integration challenge topics : • New Torsen type D > achieves a new strength / compactness ratio landmark • Torsen LSD improves both Performance & Safety > maximize advantages & eliminate disturbances : & 1. "TOC" EPS tuning eliminates torque-steer while ensuring natural steering feel 2. ESC tuning eliminates initial understeer and boosts corrective yaw moments 3. Chassis tuning reduces initial understeer as well as unsmooth yaw transients + achieves adequate vehicle natural yaw balance 2 Torsen is a registered trademark of JTEKT Corporation PROPRIETARY JTEKT CORPORATION Torsen LSD integration challenge topics : • New Torsen type D > achieves a new strength / compactness ratio landmark • Torsen LSD improves both Performance & Safety > maximize advantages & eliminate disturbances : 1. "TOC" EPS tuning eliminates torque-steer while ensuring natural steering feel 2. ESC tuning eliminates initial understeer and boosts corrective yaw moments 3. Chassis tuning reduces initial understeer as well as unsmooth yaw transients + achieves adequate vehicle natural yaw balance 3 Torsen is a registered trademark of JTEKT Corporation PROPRIETARY JTEKT CORPORATION Torsen type D : robust & compact Size & Weight Reduction Smaller module & Lower helix angle Larger module & Higher helix angle 4 Torsen is a registered trademark of JTEKT Corporation PROPRIETARY JTEKT CORPORATION Torsen LSD integration challenge topics : • New Torsen type D > achieves a new strength / compactness ratio landmark • Torsen LSD improves both Performance & Safety > maximize advantages & eliminate disturbances : & 1. "TOC" EPS tuning eliminates torque-steer while ensuring natural steering feel 2.
    [Show full text]
  • SAE Vehicle Dynamics Technology Collection : Technical Papers
    SAE Vehicle Dynamics Technology Collection : Technical Papers 11th Annual SAE Brake Colloquium and Engineering Display 933070 Title: RTV—A friction material designers view 933071 Title: Practical evaluation and FEM-modelling of a squealing disc brake 933072 Title: Geometric induced instability in drum brakes 14th Annual Brake Colloquium and Engineering Display 962128 Title: Experimental analysis of low-frequency brake squeal noise 962130 Title: Development of correlation between experimental and analytical modal analysis of brake pads 17th Annual Brake Colloquium and Engineering Display 1999-01-3400 Title: Disc brake corner system modeling and simulation Title: A proposal to predict the noise frequency of a disc brake based on the friction pair interface 1999-01-3403 geometry 1999-01-3405 Title: Global NVH matrix for brake noise—A Bosch proposal 1999-01-3407 Title: Prediction of damping treatment dynamics as bonded to a brake shoe and lining Title: An experimental investigation of disk brake creep-groan in vehicles and brake dynamometer 1999-01-3408 correlation 1999-01-3410 Title: Calculation of average coefficient of friction during braking 18th Annual Brake Colloquium and Engineering Display 2000-01-2753 Title: Dynamic modeling of brake friction coefficients 2000-01-2760 Title: Ultra Q™process 2000-01-2763 Title: Cost-effective Aluminium MMC brake discs 2000-01-2764 Title: Modal participation analysis for identifying brake squeal mechanism 2000-01-2765 Title: On the analysis of brake squeal propensity using finite element method 2000-01-2766
    [Show full text]
  • Steering Drift and Wheel Movement During Braking: Parameter Sensitivity Studies
    Steering drift and wheel movement during braking: parameter sensitivity studies Item Type Article Authors Klaps, J.; Day, Andrew J. Citation Klaps, J. and Day, A.J. (2003). Steering drift and wheel movement during braking: parameter sensitivity studies. Proceedings of the Institution of Mechanical Engineers D: Journal of Automobile Engineering. Vol. 217, No. 12, pp. 1107-1115. Rights © 2003 IMechE. Reproduced in accordance with the publisher's self-archiving policy. Download date 24/09/2021 19:01:02 Link to Item http://hdl.handle.net/10454/882 1107 Steering drift and wheel movement during braking: parameter sensitivity studies J Klaps1 and A J Day2* 1Ford Motor Company,Belgium 2School of Engineering,Design and Technology, University of Bradford, Bradford, UK Abstract: In spite of the manysigni cant improvements in carchassis design over the past two decades, steering drift during braking where the driver must applya corrective steering torque in order to maintain course canstill be experienced under certain conditions whiledriving. In the past, such drift, or ‘pull’, would havebeen attributed to side-to-side braking torque variation[ 1], but modern automotive friction brakes and friction materialsare now ableto provide braking torque with such high levelsof consistency that side-to-side braking torque variationis no longer regarded asacause of steering drift during braking. Consequently, other inuences must be considered. This paper isthe rst of two papers to report on anexperimental investigation into braking-related steering drift in motor vehicles.Parameters that might inuence steering drift during braking include suspen- sion compliance and steering o set, and these havebeen investigated to establish the sensitivity of steering drift to such parameters.
    [Show full text]
  • MINI Compare Models 2011 Specifications-Pdf
    LET’S FORGET ALL OUR ASSUMPTIONS ABOUT CARS. If you’re going to motor, motor in a strange and wonderful alchemy of steel, aluminum, graphite, dreams and sweat. Motor in something built by designers who used paper and pencil instead of computers. By designers who listened to their hearts, not focus groups. Motor in a machine that’s more than a pretty face. Every MINI is small but packed with as many features as some cars costing three times as much. Read on and soon you’ll understand that even though there are three different body types, the MINI is still in a class of one. Cooper Cooper S Cooper Cooper S Cooper Cooper S Cooper Cooper S Cooper S John John Cooper John Cooper LET’S BE SMART. Hardtop Hardtop Convert. Convert. Clubman Clubman Countryman Countryman Countryman Cooper Works Works ALL4 Works Convert. Clubman 6 standard airbags w/ side curtains: Smart technology knows which airbags need to inflate when, and at what speed and force* 7 standard airbags w/ side curtains: Smart technology knows which airbags need to inflate when, and at what speed and force* Active Rollover Protection Bars and reinforced A-pillar and frame Four standard airbags: Smart technology knows which airbags need to inflate when, and at what speed and force* Side thorax airbags in the sides of the front seats that protect the bodies and the heads of the driver and front co-pilot* Advanced crumple zones re-channel forces around the passenger compartment The latest generation 4-channel Anti-lock Braking System (ABS). Vented front, solid back.
    [Show full text]
  • Alignment Theory Manual
    Fundamentals of Suspension & 4-Wheel Alignment Interactive Multimedia Edition Toe Toe In Out Copyright 1996 Fundamentals of Suspension & 4-Wheel Alignment Page - 2 Personal Notes Table of Contents SPRINGS ------------------------------------------------------------------------- 5 TORSION BARS ------------------------------------------------------------------------- 6 COIL SPRINGS ------------------------------------------------------------------------- 6 LEAF SPRINGS ------------------------------------------------------------------------- 7 AIR SPRINGS ------------------------------------------------------------------------- 8 SHOCK ABSORBERS ------------------------------------------------------------------------- 9 MACPHERSON STRUT ------------------------------------------------------------------------- 11 CONTROL ARMS ------------------------------------------------------------------------- 13 BALL JOINTS ------------------------------------------------------------------------- 15 STRUT ROD/BUSHINGS ------------------------------------------------------------------------- 18 SWAY BAR SYSTEM ------------------------------------------------------------------------- 19 STEERING SYSTEM ------------------------------------------------------------------------- 20 STEERING LINKAGES ------------------------------------------------------------------------- 22 PITMAN ARM ------------------------------------------------------------------------- 23 IDLER ARM ------------------------------------------------------------------------- 24 CENTER
    [Show full text]