High Speed Off-Road Vehicles Automotive Series Series Editor: Thomas Kurfess High Speed Off-Road Vehicles: Suspensions, Tracks, Wheels and Dynamics Maclaurin July 2018 Hybrid Electric Vehicles: Principles and Applications with Practical Perspectives, 2nd Edition Mi and Masrur October 2017 Hybrid Electric Vehicle System Modeling and Control, 2nd Edition Liu April 2017 Thermal Management of Electric Vehicle Battery Systems Dincer, Hamut and Javani March 2017 Automotive Aerodynamics Katz April 2016 The Global Automotive Industry Nieuwenhuis and Wells September 2015 Vehicle Dynamics Meywerk May 2015 Vehicle Gearbox Noise and Vibration: Measurement, Signal Analysis, Signal Processing and Noise Reduction Measures Tůma April 2014 Modeling and Control of Engines and Drivelines Eriksson and Nielsen April 2014 Modelling, Simulation and Control of Two-Wheeled Vehicles Tanelli, Corno and Savaresi March 2014 Advanced Composite Materials for Automotive Applications: Structural Integrity and Crashworthiness Elmarakbi December 2013 Guide to Load Analysis for Durability in Vehicle Engineering Johannesson and Speckert November 2013 High Speed Off-Road Vehicles Suspensions, Tracks, Wheels and Dynamics Bruce Maclaurin Retired ex Ministry of Defence UK This edition first published 2018 © 2018 John Wiley & Sons Ltd All rights reserved No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by law Advice on how to obtain permission to reuse material from this title is available at http://www.wiley.com/go/permissions The right of Bruce Maclaurin to be identified as the author of this work has been asserted in accordance with law Registered Office(s) John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK Editorial Office The Atrium, 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John Wiley & Sons, 2018 | Series: Automotive series | Includes bibliographical references and index | Identifiers: LCCN 2018007653 (print) | LCCN 2018012003 (ebook) | ISBN 9781119258803 (pdf ) | ISBN 9781119258810 (epub) | ISBN 9781119258780 (cloth) Subjects: LCSH: Off-road vehicles Classification: LCC TL235.6 (ebook) | LCC TL235.6 M25 2018 (print) | DDC 629.228/8–dc23 LC record available at https://lccn.loc.gov/2018007653 Cover Design: Wiley Cover Images: Background: © solarseven/Shutterstock; Left: Range Rover Sport Offroad Presentation by Wachauring is licensed under CC BY-SA; Middle: © Rockfinder/Gettyimages; Right: Reservists Train to be Challenger tank crew, WMID-2013-044-350 © Crown Copyright 2013 Set in 10/12pt WarnockPro by SPi Global, Chennai, India 10 9 8 7 6 5 4 3 2 1 ffirs.indd 6/7/2018 12:15:57 PM To the late Professor David Crolla, whose advice, knowledge, encouragement and humour are sorely missed To my wife Jacqueline, for her encouragement and tolerance of my many hours communing with journals, papers, books and my computer vii Contents Series Preface xiii Acknowledgements xv Introduction xvii Tracked Vehicle Running Gear and Suspension Systems 1.1 General Arrangement 1.2 Transverse Torsion Bars 1.3 Coil Springs 1.4 Hydrogas Suspensions 1.4.1 Challenger MBT Hydrogas Unit 1.4.2 Measured Characteristics of a Challenger Unit 1.4.2.1 Spring Characteristics 1.4.2.2 Damper Characteristic 11 1.4.2.3 Differential Pressure Across the Damper Valve 11 1.4.2.4 Force/Displacement Loop 11 1.4.2.5 Flow Rig 12 1.4.2.6 Suspension Damping of a Multi‐Wheeled Vehicle 13 1.4.3 Temperature Effects 13 1.4.3.1 Two‐Stage Units 15 1.4.3.2 Counter‐Spring Units 17 1.4.4 Other Types of Hydrogas Suspension 18 1.4.4.1 Twin‐Cylinder Units 18 1.4.4.2 In‐Arm Units 18 1.5 Dampers 20 1.5.1 Hydraulic Dampers 20 1.5.2 Friction Dampers 20 References 22 2.1 2.1.1 2.1.1.1 2.1.1.2 2.1.2 Vehicle Track Systems 23 Link Tracks 23 Single‐Pin Tracks 26 Dry‐Pin Tracks 26 Rubber‐Bushed Tracks 27 Double‐Pin Tracks 28 viii Contents 2.1.3 Rubber Track Pads, Road Wheels and Track Tensioners 31 2.1.3.1 Rubber Track Pads 31 2.1.3.2 Road Wheels 32 2.1.3.3 Track Tensioners 33 2.1.4 Track Loadings 33 2.1.4.1 Centrifugal Tension 33 2.1.4.2 Final‐Drive Torque Measurements 34 2.1.4.3 Lateral Horn Load 35 2.1.5 Rolling Resistance: Analytical Methods 35 2.1.5.1 On a Metal Wheel Path 35 2.1.5.2 On a Rubber Wheel Path 36 2.1.6 Rolling Resistance: Experimental Measurements 37 2.1.6.1 Chieftain 38 2.1.6.2 FV 432 39 2.1.6.3 Scorpion and Spartan 40 2.1.6.4 Summary 42 2.1.7 Noise and Vibration 42 2.1.8 Approaches for Reducing Noise and Vibration 43 2.1.8.1 Finite Element Analysis and Experimental Sprockets 43 2.1.8.2 Fully Decoupled Running Gear 44 2.1.8.3 Flexible Rubber Tracks 44 2.1.9 Reducing Noise and Vibration 44 2.1.9.1 Stage (a): Establishing the Principal Noise Sources 45 2.1.9.2 Stage (b): Design and Production of the Resilient Mountings 46 2.1.9.3 Stage (c): Test Results with the Resilient Mountings 47 2.2 Flexible Tracks 48 2.2.1 Earlier Flexible Tracks 49 2.2.2 Contemporary Flexible Tracks 50 2.2.3 ‘Proof‐of‐Principle’ Flexible Tracks for a Spartan APC 51 2.2.3.1 Mark Tracks 53 2.2.3.2 Mark Tracks 54 2.2.3.3 Mark Tracks 55 2.2.3.4 Durability Trials 57 2.2.4 Later Developments 57 References 58 Tracked Vehicle Suspension Performance: Modelling and Testing 59 3.1 Human Response to Whole‐Body Vibration (WBV) and Shock 59 3.1.1 BS 6841:1987 and ISO 2631‐1 (1997) 59 3.1.2 Further Standards Relating to WBV 61 3.1.2.1 Absorbed Power 61 3.1.2.2 The European Physical Agents (Vibration) Directive 2002/44/EC 64 3.1.2.3 ISO 2631‐5 (2004) 64 3.2 Terrain Profiles 64 3.2.1 Characterisation 64 3.2.2 DERA Suspension Performance Test Courses 65 3.2.3 Response of Multi‐Wheel Vehicles 66 Notation S(f) T V V W w zg zs zu αa αd ζ θ μ ωs ωu PSD in terms of frequency (Hz) time of exposure vertical velocity of seat base vehicle forwards speed vehicle weight (kN) terrain wavelength terrain profile displacement sprung mass displacement unsprung mass displacement approach angle departure angle damping ratio pitch angle ratio unsprung mass/sprung mass sprung mass natural frequency (rad s–1) unsprung mass natural frequency (rad s–1) Chapter 4 KB KM MB MM CB CM stiffness of the main body spring stiffness of the model spring mass of the main body mass of the model damping coefficient of the main body damping coefficient of the model Chapter 5 A fn n Ka Kh Kw K1 K2 KϕF KϕR V piston area of an air spring natural frequency polytropic index stiffness of an air spring vehicle heave stiffness warp stiffness stiffness at the wheel of the pitch interconnection spring stiffness at the wheel of the pure heave spring front axle roll stiffness rear axle roll stiffness volume of an air spring Chapter 6 Ccr Ceq k m critical damping coefficient equivalent damping coefficient stiffness of the spring mass carried by the spring 237 238 Notation X μ ω amplitude of vibration coefficient of friction frequency of vibration (rad s–1) Chapter 7 a length of track pad in x direction of track A area of track pad As, Bs, Cs, Ds shafts in double differential (Figure 7.4) B, C, D, E Magic Formula primary parameters , , , normalised parameters in Magic Formula B C D E Cα, Cs lateral and longitudinal force–slip stiffness Cfx, Cfy longitudinal and lateral slip stiffness of tyres CF centrifugal force CFx, CFy longitudinal and lateral components of centrifugal force CG centre of gravity c half the distance between track centres d horizontal distance between mid‐wheelbase and centre of sprocket/idler FDf, FDr components of drive force front and rear of outer sprocket FBf, FBr components braking force front and rear of inner sprocket Fpt track pretension force ΣFxo, FD sum of longitudinal forces on outer (drive) track ΣFxi, FB sum of longitudinal forces on inner (braking) track ΣFyo, ΣFyi sum of lateral forces on outer and inner tracks ΣFy1, ΣFy2 sum of lateral forces on axle 1, 2, etc Fx, Fy longitudinal and lateral forces on tyres Fx,max, Fy,max peak longitudinal and lateral forces on tyres Fr rolling resistance of tyres Fs normalised combined slip force Fzs static normal load on wheel/pad Fzr, Fzp normal loads on pads due to roll and pitch moments Fzt normal loads on pads due to vertical components of track forces G shear modulus of track pad rubber h height of CG k ratio of track longitudinal stiffness (sprocket to ground/sprocket to idler to ground) Ks shear stiffness of a track pad l half the wheelbase Mp, Mr pitch and roll moments Pp power for a pivot or neutral turn Po, Pi outer and inner shaft powers Pd drive power Ps steer power Pnt total net power R radius of turn to CG re effective sprocket radius combined slip sc Notation sy lateral slip sxt, sxb longitudinal slip in traction and braking t depth of track pad To, Ti, Td, Ts outer, inner, drive and steer shaft torques (Figures 7.1 and 7.4) x1, x2 distance from CG to axle 1, 2, etc xm slip value at maximum force in Magic Formula v peripheral velocity of tyre ya force value at maximum slip in Magic Formula vt track velocity in relation to wheel centre vx longitudinal velocity of wheel centre vo, vi outer and inner track velocities in relation to wheel centre, peripheral velocities of tyres Δv velocity difference between inner and outer wheels V velocity at CG W weight of vehicle X slip angle or longitudinal slip in Magic Formula β sideslip angle at CG γf, γr track angle at front and rear of vehicle (tangent from sprocket/idler to wheel and ground) , , normalised slip parameters δ front wheel steer angle κ, κb, κt tractive slip λ combined slip ωp angular rate of vehicle for a pivot or neutral turn Ωo, Ωi, Ωd, Ωs outer, inner, drive and steer shaft speeds (Figures 7.1 and 7.4) Chapter 8 b B, C, D, E ct CG CR CT CT20 CTP CI d FG FR FT h NC NM NMS NRR NGT tyre width primary coefficients in the Magic Formula cohesion from triaxial test gross traction coefficient rolling resistance coefficient net traction coefficient coefficient of net traction at 20% slip peak net traction coefficient cone index tyre diameter gross tractive force rolling resistance force net tractive force tyre section height expression for cohesive soils (Turnage) expression for cohesive soils expression for tyres with small deflection expression for rolling resistance in cohesive soils expression for gross traction in cohesive soils 239 240 Notation NS NSN N T N TS re rs rr R s sv SH, SV T V W x, X xm y, Y δ ω WES expression for sandy soils NRMM expression for sandy soils expression for tracked vehicles in cohesive soils expression for tracked vehicles in sandy soils effective tyre rolling radius static radius of tyre, wheel centre to ground rolling radius of tyre on a hard surface, free rolling normal reaction of tyre at ground surface longitudinal slip shear stress from simple shear vane horizontal and vertical shifts in the Magic Formula input torque forward velocity of the wheel vertical load on the wheel slip parameters in the Magic Formula slip at peak force in the Magic Formula force parameters in the Magic Formula tyre deflection on a hard surface rotational speed of wheel Chapter 9 FD equivalent transfer force in the differential FG gross tractive force FGF gross tractive force on faster‐running wheel FGFD gross tractive force of the faster‐running wheel as given by the differential transfer force FGFM gross tractive force of the faster‐running wheel as given by the Magic Formula FGS gross tractive force on slower‐running wheel FI equivalent input force to the differential FR rolling resistance force FT net tractive force FTF net tractive force of the faster‐running wheel FTS net tractive force of the slower‐running wheel Kd transfer ratio of proportional load differential PI input power to the differentials PI power dissipated in the differential ‘clutch’ Po output power of the vehicle re effective rolling radius s slip sf slip of the faster‐running wheel ss slip of the slower‐running wheel TD torque transfer in diff (clutch) TF torque to faster‐running wheel TI torque input to differential torque to slower‐running wheel TS Notation T W vf v i vs vt VV W ωf ωi ωs ωw input torque to wheel peripheral velocity of the faster‐running wheel equivalent input speed to the differential peripheral velocity of the slower‐running wheel peripheral velocity of tyre forward velocity of the wheel or vehicle vertical load on the tyre rotational velocity of the faster‐running wheel rotational input velocity of the differential rotational velocity of the slower‐running wheel rotational speed of the wheel Chapter 11 ay Fi FL Fo h t W Φ lateral acceleration (g units) vertical force at the inner wheel lateral force at the CG vertical force at the outer wheel height of the CG vehicle track vehicle weight body roll angle 241 243 Abbreviations AP APC ASAARL ASCOD ATZ BS CAD CG CI DBP DERA DROPS ERDC ESP FEM GDELS GVW IED IFV IRHD ISO ISTVS KMW MBT MI MMP MMPL NATO NRMM PCD PSD RCI RI RMQ RMS absorbed power, Automotive Products armoured personnel carrier US Army Aeromedical Research Laboratory Austrian Spanish Cooperation Development Automobiltechnische Zeitschrift British Standard computer‐aided design centre of gravity cone index drawbar pull Defence Evaluation and Research Agency demountable rack offload and pickup system Engineer Research and Development Centre electronic stability programme finite‐element modelling General Dynamics European Land Systems gross vehicle weight improvised explosive device infantry fighting vehicle International Rubber Hardness Degree International Standards Organisation International Society for Terrain‐Vehicle Systems Krauss Maffei Wegmann main battle tank mobility index mean maximum pressure limiting go/no‐go soil strength (CI) for the MMP method North Atlantic Treaty Organisation NATO Reference Mobility Model pitch circle diameter power spectral density rating cone index remoulding index root mean quad root mean square High Speed Off-Road Vehicles: Suspensions, Tracks, Wheels and Dynamics, First Edition Bruce Maclaurin © 2018 John Wiley & Sons Ltd Published 2018 by John Wiley & Sons Ltd 244 Abbreviations SRT TACOM TARDEC VCI VDV VLCI WBV WES static rollover threshold Tank Automotive and Armaments Command Tank Automotive Research, Development and Engineering Centre vehicle cone index vibration dose value vehicle limiting cone index whole‐body vibration Waterways Experiment Station (now ERDC) 245 Bibliography Gillespie, T D (1992) Fundamentals of Vehicle Dynamics Society of Automotive Engineers Wong, J Y (2001) Theory of Ground Vehicles John Wiley and Sons Pacejka, H B (2002) Tyre and Vehicle Dynamics Elsevier Butterworth‐Heinemann Mastinu, G and Ploechl, M (eds) (2014) Road and Off‐Road System Dynamics CRC Press, Taylor and Francis Group Reif, K R (ed.) (2014) Automotive Handbook Bosch GmbH Milliken, W F and Milliken, D L (1995) Race Car Vehicle Dynamics Society of Automotive Engineers Ogorkiewicz, R M (1968) Design and Development of Fighting Vehicles Macdonald & 10 11 Co Ltd Ogorkiewicz, R M (2015) Tanks, 100 Years of Evolution Osprey Publishing Heißing, B and Ersoy, M (2011) Chassis Handbook Vieweg + Teubner Griffin, M J (1990) Handbook of Human Vibration Academic Press Bekker, M G (1969) Introduction to Terrain-Vehicle Systems The University of Michigan Press High Speed Off-Road Vehicles: Suspensions, Tracks, Wheels and Dynamics, First Edition Bruce Maclaurin © 2018 John Wiley & Sons Ltd Published 2018 by John Wiley & Sons Ltd 247 Index a c Active suspensions 89–100 fast active (wide bandwidth) 97–100 slow active (narrow bandwidth) 93–97 ADM (Automatic Drive‐Train Management System) 203 Air springs natural frequency 107 ride height control 106 stiffness 106 Anthony Best Dynamics 46 Anti‐roll bars 117 Armoured Personnel Carriers see also Infantry Fighting Vehicle; Reconnaissance Vehicle FV432 27, 35, 38–40, 93 M113 44, 48, 52, 55, 219–220 Spartan 38–40, 45–46, 48, 53, 74, 140–143 Stormer 4, 20, 222 Warrior 1, 20, 33, 74, 75, 199 Articulated vehicles, tracked 217–222 BV 206 217 BVS 10 217 COBRA–positive pitch control 219 coupled M113s 219 Tucker SNO‐CAT 217 UDES XX20 220 Vityaz 221 Articulated vehicles, wheeled 222–226 GOER 223 MARV 224 Twister 224 Automotive products 94 Cambridge University Engineering Department 230 Caterpillar Inc. 50, 108 Central tyre inflation system (CTIS) 129 Challenger hydrogas unit, characteristics 8–18 damper characteristics 11–13 spring stiffness characteristics 9–11 temperature effects 13–18 Coil springs nested 7 presetting or ‘scragging’ tracked in bogie in trailing arm 6, Wahl factor wheeled, with axles 105 McPherson struts 107, 113 swing axles 105 trailing arms 112, 113 twin wishbones 107, 115 Cone penetrometer 180 Controllable suspensions active 91–100 adaptive damping 91 height and attitude control 89–91 semi‐active (controllable damping) 91 d Dampers friction 1, 19, 20, 94, 117, 131 hydraulic 1, 20, 129 High Speed Off-Road Vehicles: Suspensions, Tracks, Wheels and Dynamics, First Edition Bruce Maclaurin © 2018 John Wiley & Sons Ltd Published 2018 by John Wiley & Sons Ltd 248 Index DERA Suspension Performance Test Courses 65 ramps 62 random 62 sinewaves 62 Differentials double 90, 133–137, 167, 173, 174 free 166, 188, 211 limited slip 196, 203–208, 214, 215 lockable 133, 203, 204, 210, 211, 214, 215 Double differential types 133–137 Dowty Rotol 103, 110, 193 Driver control arrangements for skid steering 146 DROPS (demountable rack offload and pickup system) 103, 125, 127, 230 e Electronic stability program (ESP) 168, 230 h Human response to vibration and shock absorbed power 61, 63, 229 BS 6841:1987 59–64, 70, 71, 78 exposure action values 64 exposure limit values 64 ISO 2631–1 (1987) 63 ISO 2631–5 (2004) 59.61, 63 root mean quad weighted 61 root mean square weighted 60 vibration dose value 61 vibration response weighting filters 59, 60 Hydrogas springs 6, 8–18, 85, 89, 90, 95, 108, 113, 116, 118, 121 with external telescopic unit 19 in‐arm units 18, 19 twin cylinder units 18 i Infantry Fighting Vehicle 1, 20, 115 Interconnected suspensions 116–122 methods of interconnection 116–118 in pitch 117–119 in pitch Citroen 2CV 117–119 in roll 117 in roll and pitch 118 six wheel interconnection 121, 122 in warp 119–122 k Kegresse flexible track 49 Citroen half‐track truck with Kegresse flexible track 49 Krauss Maffei Wegmann (KMW) 44 l Leaf springs 103, 104, 217, 227 bogie with swing axles 105 bogie with twin axles 103 equivalent viscous damping 131 friction 131 with swing axles 103 Limited slip differentials 113, 196, 203–205 ADM (Automatic Drive‐Train Management System) 203 frictional, load dependant 205–215 NoSpin 108, 166, 167 velocity dependant 204 Liquid springs 93, 110–112 Lotus Engineering 97 m Magic Formula 139–143, 158, 159, 170, 198–201, 209 track longitudinal force/slip characteristics on roads 139–143 tyre combined force/slip characteristics on roads (Sharp) 158, 159 tyre longitudinal force/slip characteristics in cohesive soils 198–201 Main battle tanks (MBTs) Abrams 20, 31, 36, 89 Centurion 7 Challenger 8–18, 26, 31, 32, 66, 76–79, 83–86 Chieftain 7, 34, 37, 39, 193, 194 Cromwell 6 K2 Black Panther 19 Khalid 7, 26, 27, 32 Leclerc 18 Leopard 2 1, 20, 21, 31, 33, 135 M 60 33 MBT‐70 89 Merkava 8, 26 Panther 4 Index S‐tank 89, 90 MAN trucks 105 Mars rover ‘Curiosity’ 120–122 Mean maximum pressure (MMP) 182, 183, 187, 188 Merritt steering model 136, 146, 159 Mobile tester (DERA) 183, 188, 196–199, 209 Mobility numbers NC (WES cohesive soil) 182 NM (DERA cohesive soil) 185, 225 NMS (DERA cohesive soil small tyre deflection) 186 NSN (NRMM frictional soil) 189 NS (WES frictional soil) 189, 192 N T (DERA cohesive soil track systems) 188 NTP (Tyre peak coefficient traction) 199 n Nexter Systems 18, 91, 113, 156 NRMM (NATO Reference Mobility Model) 61–63, 177, 180, 182, 190, 193, 195, 199 q QinetiQ tracked vehicle electric drive steering system 154 Quarter car model 68, 92, 123, 129 damping 69 natural frequency 69, 124 RMS dynamic suspension displacement 123 RMS dynamic tyre load 123 sprung/ unsprung weight 125 tyre pressure 125 weighted RMS body acceleration 70, 124 with wheelbase filter tracked 70 with wheelbase filter wheeled 126 r Radial ply tyres rolling radius 199, 200 rolling stiffness and damping 131, 132 soft soil performance (DERA mobile tester) 185 Reconnaissance Vehicle 115–117 Renk MBT transmission 135 Rollover 227–233 active anti‐roll bars 230, 232 electronic Stability Programs 230 static Rollover Threshold (SRT) 227 tilt table 228 truck rollover; a case study 230 s SITV (Sprung idler test vehicle) 85–87 Soils and surfaces 177, 178 cohesive (wet clays) 177, 178 frictional (dry sands) 178 organic 177 road (dry, wet, slippery, icy, split μ) 209 snow 178 Soil strength measurement methods Bekker, M.G. 180 cone Index 180 cone index gradient 189, 192 cone penetrometer 180 Coulomb 177 rating cone index 180 shear vane (shear strength) 192, 200 Terzaghi (civil engineering) 178 triaxial test (laboratory method) 200 Wong, J.Y. 180, 197 Soil/vehicle models Bekker, M.G. 180 FEM 180 MMP (Rowland) 182, 183 VCI (WES) 180–183 VLCI (DERA) 183–188 Wong, J.Y. 180, 197 Space efficiency, tracks v wheels 194, 195 Sprung cab 129 t Torque vectoring 166, 167, 169, 205 Torsion bars springs presetting 2 stresses 3 tracked transverse with trailing arms wheeled transverse with trailing arms 113 twin wishbones 108 249 250 Index Track loadings cross bending 29 tensile centrifugal 34 duty cycle 34 vehicle drive 29, 30, 36 Track pads 31–32 Track performance noise and vibration 43–48 rolling resistance, analytical 36–38 rolling resistance, experimental 38–43 Tracks, flexible continuous, friction drive 50 continuous, sprocket drive 53–58 segmented 51, 52 wrapped with single connector 50 Tracks, link tracks double pin 28 double bodies and three connectors 29 single body and three connectors 29, 30 single body and two connectors 28 weight 31 single pin 23 needle bearings 26 plain pivot (dry pin) 26, 27 rubber bushed 27, 28 Tracks, soucy flexible DERA performance trials 53–56 performance and durability with standard road and cross country duty cycle 57 Track wheels 32, 33 Tractive efficiency 50, 196, 208, 210 v Vedovelli Priestley 133, 154 w Wheelbase filter 66–68, 70, 101, 126 Wheeled vehicle driveline systems H‐drive 103, 107, 112, 113 I‐drive 103 113–115 Wheeled vehicles armoured AMX 10RC 91, 113, 156, 157, 159, 195 Boxer 114, 115 Ferret 113 Fox 115 Luchs 115 Panhard AML 112, 113 Panhard EBR 113 Piranha 113, 114 Saladin 107 Saracen 106 Wheeled vehicles (unarmoured) Caterpillar mining truck 108 Euclid/Hitachi mining truck 110 Leyland DROPS 103, 125, 127, 129, 230, 231 MAN SX 8x8 105 Pinzgauer 105 Range Rover 106, 107 Stalwart 107 Wheeled vehicle suspension systems axle with coil springs and control links 105 axle with leaf springs 103 double wishbones 107, 108 McPherson strut 107, 113 swing axle 106 telescopic with integral steering pivot 108 trailing arms with drive shaft 113 trailing arms with internal transmission gearing 112, 113 ZF 206, 208 WILEY END USER LICENSE AGREEMENT Go to www.wiley.com/go/eula to access Wiley’s ebook EULA ... High Speed Off-Road Vehicles Automotive Series Series Editor: Thomas Kurfess High Speed Off-Road Vehicles: Suspensions, Tracks, Wheels and Dynamics Maclaurin July 2018 Hybrid Electric Vehicles: ... for Durability in Vehicle Engineering Johannesson and Speckert November 2013 High Speed Off-Road Vehicles Suspensions, Tracks, Wheels and Dynamics Bruce Maclaurin Retired ex Ministry of Defence... front three and rear two axle arm pivots The vehicle is fitted with rubber‐bushed double‐pin tracks (see Chapter 2) High Speed Off-Road Vehicles: Suspensions, Tracks, Wheels and Dynamics, First