4569846498

More documents

Recommendations

Info

Simulation output and interpretation 437 on. The combination of design variables is selected to maximize signal-tonoise ratio to maximize robustness of the system. The following steps in the process are the adjustments to the sensitivity, , being made through those variables showing themselves as affecting but of less influence on . Such an approach to the ideal function for the steering and handling behaviour covers a great many different situations although for motorsport applications, in particular rallying, it may lack one important aspect. Rally drivers use the non-linearity of the car to their advantage. Recall the force–moment diagram in Figure 7.29. This is derived on the basis of quasi-static calculations. However, professional rally drivers use the dynamic amplification of the yaw–sideslip resonance along with features such as ruts and road surface edges (Figure 7.35) to achieve yaw accelerations significantly greater than that suggested by the Milliken moment method, as shown by the comparison in Figure 7.36. The lightest data in the centre represents the highest speeds achieved during the stage and fits well within the estimated boundaries of the F–M diagram. However, the two other shades show extremely large levels of yaw acceleration at high lateral acceleration in strong contrast to the general form of the Milliken diagram. This is a symptom of the use of the dynamic amplification in the yaw–sideslip mode as used by the rally drivers. The use of an ideal function that relates steer angle to yaw rate will promote an increase in yaw damping, which is good for road cars but precludes the ‘flick’ style of driving preferred by rally drivers. Figure 7.37, by contrast, shows the behaviour of the rally car on tarmac and suggests that the vehicle stays well within the quasi-static boundary predicted by the Milliken moment method. Fig. 7.35 Tommi Makinen hooks the front left wheel of his 2003 Subaru WRC off the tarmac and ensures a large yaw moment will be available shortly (courtesy of Prodrive)
438 Multibody Systems Approach to Vehicle Dynamics Yaw acceleration (deg/s/s) 1000 800 600 400 200 0 200 400 600 Predicted CN – A y boundary Measured data 0–90 kph Measured data 90–130 kph Measured data 130–250 kph 800 1000 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 Lateral acceleration (g) Fig. 7.36 Yaw acceleration versus lateral acceleration for the Subaru WRC 2002, Petter Solberg, Argentina Yaw acceleration (deg/s/s) 1000 800 600 400 200 0 200 400 Predicted CN–A y boundary Measured data 0–90 kph Measured data 90–130 kph Measured data 130–250 kph 600 800 1000 2.5 2.0 1.5 1.0 0.5 0.0 0.5 1.0 1.5 2.0 2.5 Lateral acceleration (g) Fig. 7.37 Yaw acceleration versus lateral acceleration for Subaru WRC 2002, Petter Solberg, Germany Examination of the recorded data shows there is little ‘steady state’ about the rally stage on loose surfaces and the character of the handwheel angle versus yaw rate trace for the entire stage has a distinctly ‘circular’ quality about it (Figure 7.38). This indicates that output (yaw) has a phase shift of around 90 degrees – an indication that the system is indeed at resonance. In
Page 2 and 3:
Multibody Systems Approach to Vehic
Page 4 and 5:
Multibody Systems Approach to Vehic
Page 6 and 7:
Contents Preface Acknowledgements N
Page 8 and 9:
Contents vii 4.10.1 Problem definit
Page 10 and 11:
Contents ix 8.2.1 Active suspension
Page 12 and 13:
Preface This book is intended to br
Page 14 and 15:
Preface xiii vehicle design process
Page 16 and 17:
Acknowledgements Mike Blundell In d
Page 18 and 19:
Nomenclature xvii {z I } 1 Unit vec
Page 20 and 21:
Nomenclature xix O n Frame for part
Page 22 and 23:
Nomenclature xxi p Magnitude of re
Page 24 and 25:
1 Introduction The most cost-effect
Page 26 and 27:
Introduction 3 subsequent ‘classi
Page 28 and 29:
Introduction 5 Fig. 1.4 Linearity:
Page 30 and 31:
Introduction 7 While apparently a s
Page 32 and 33:
Introduction 9 3. The body yaws (ro
Page 34 and 35:
Introduction 11 Aspiration Definiti
Page 36 and 37:
Introduction 13 Decomposition: Synt
Page 38 and 39:
Introduction 15 The best multibody
Page 40 and 41:
Introduction 17 shows good correlat
Page 42 and 43:
Introduction 19 generated in numeri
Page 44 and 45:
Introduction 21 1.9 Benchmarking ex
Page 46 and 47:
2 Kinematics and dynamics of rigid
Page 48 and 49:
Kinematics and dynamics of rigid bo
Page 50 and 51:
Page 52 and 53:
Page 54 and 55:
Page 56 and 57:
Page 58 and 59:
Page 60 and 61:
Page 62 and 63:
Page 64 and 65:
Page 66 and 67:
Page 68 and 69:
Page 70 and 71:
Page 72 and 73:
Page 74 and 75:
Page 76 and 77:
Page 78 and 79:
Page 80 and 81:
Page 82 and 83:
Page 84 and 85:
Page 86 and 87:
Page 88 and 89:
Page 90 and 91:
Page 92 and 93:
Page 94 and 95:
Page 96 and 97:
Page 98 and 99:
3 Multibody systems simulation soft
Page 100 and 101:
Multibody systems simulation softwa
Page 102 and 103:
Page 104 and 105:
Page 106 and 107:
Page 108 and 109:
Page 110 and 111:
Page 112 and 113:
Page 114 and 115:
Page 116 and 117:
Page 118 and 119:
Page 120 and 121:
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
Page 128 and 129:
Page 130 and 131:
Page 132 and 133:
Page 134 and 135:
Page 136 and 137:
Page 138 and 139:
Page 140 and 141:
Page 142 and 143:
Page 144 and 145:
Page 146 and 147:
Page 148 and 149:
Page 150 and 151:
Page 152 and 153:
Page 154 and 155:
4 Modelling and analysis of suspens
Page 156 and 157:
Modelling and analysis of suspensio
Page 158 and 159:
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
Page 186 and 187:
Page 188 and 189:
Page 190 and 191:
Page 192 and 193:
Page 194 and 195:
Page 196 and 197:
Page 198 and 199:
Page 200 and 201:
Page 202 and 203:
Page 204 and 205:
Page 206 and 207:
Page 208 and 209:
Page 210 and 211:
Page 212 and 213:
Page 214 and 215:
Page 216 and 217:
Page 218 and 219:
Page 220 and 221:
Page 222 and 223:
Page 224 and 225:
Page 226 and 227:
Page 228 and 229:
Page 230 and 231:
Page 232 and 233:
Page 234 and 235:
Page 236 and 237:
Page 238 and 239:
Page 240 and 241:
Page 242 and 243:
Page 244 and 245:
Page 246 and 247:
Page 248 and 249:
Page 250 and 251:
Page 252 and 253:
Page 254 and 255:
Page 256 and 257:
Page 258 and 259:
Page 260 and 261:
Page 262 and 263:
Page 264 and 265:
Page 266 and 267:
Page 268 and 269:
Page 270 and 271:
Page 272 and 273:
Tyre characteristics and modelling
Page 274 and 275:
Page 276 and 277:
Page 278 and 279:
Page 280 and 281:
Page 282 and 283:
Page 284 and 285:
Page 286 and 287:
Page 288 and 289:
Page 290 and 291:
Page 292 and 293:
Page 294 and 295:
Page 296 and 297:
Page 298 and 299:
Page 300 and 301:
Page 302 and 303:
Page 304 and 305:
Page 306 and 307:
Page 308 and 309:
Page 310 and 311:
Page 312 and 313:
Page 314 and 315:
Page 316 and 317:
Page 318 and 319:
Page 320 and 321:
Page 322 and 323:
Page 324 and 325:
Page 326 and 327:
Page 328 and 329:
Page 330 and 331:
Page 332 and 333:
Page 334 and 335:
Page 336 and 337:
Page 338 and 339:
Page 340 and 341:
Page 342 and 343:
Page 344 and 345:
Page 346 and 347:
Page 348 and 349:
Page 350 and 351:
Modelling and assembly of the full
Page 352 and 353:
Page 354 and 355:
Page 356 and 357:
Page 358 and 359:
Page 360 and 361:
Page 362 and 363:
Page 364 and 365:
Page 366 and 367:
Page 368 and 369:
Page 370 and 371:
Page 372 and 373:
Page 374 and 375:
Page 376 and 377:
Page 378 and 379:
Page 380 and 381:
Page 382 and 383:
Page 384 and 385:
Page 386 and 387:
Page 388 and 389:
Page 390 and 391:
Page 392 and 393:
Page 394 and 395:
Page 396 and 397:
Page 398 and 399:
Page 400 and 401:
Page 402 and 403:
Page 404 and 405:
Page 406 and 407:
Page 408 and 409:
Page 410 and 411: Modelling and assembly of the full
Page 418 and 419: 7 Simulation output and interpretat
Page 420 and 421: Simulation output and interpretatio
Page 424 and 425: down and even more difficult to asc
Page 464 and 465: 8 Active systems 8.1 Introduction M
Page 466 and 467: Active systems 443 mechanical actua
Page 468 and 469: Active systems 445 Table 8.1 MSC.AD
Page 470 and 471: Active systems 447 Body acceleratio
Page 472 and 473: Active systems 449 impressions of t
Page 474 and 475: Active systems 451 For this reason,
Page 476 and 477: Appendix A: Vehicle model system sc
Page 496 and 497: Appendix B: Fortran tyre model subr
Page 510 and 511:
Appendix C: Glossary of terms Agili
Page 512 and 513:
Appendix C: Glossary of terms 489 a
Page 514 and 515:
Appendix C: Glossary of terms 491 t
Page 516 and 517:
Appendix C: Glossary of terms 493 e
Page 518 and 519:
Appendix C: Glossary of terms 495 m
Page 520 and 521:
Appendix C: Glossary of terms 497 h
Page 522 and 523:
Appendix C: Glossary of terms 499 t
Page 524 and 525:
Appendix C: Glossary of terms 501 s
Page 526 and 527:
References 503 Blundell, M.V. The m
Page 528 and 529:
References 505 Hudi, J. AMIGO - A m
Page 530 and 531:
References 507 Palmer, D. Course no
Page 532 and 533:
References 509 European ADAMS News
Page 534 and 535:
Index Abuse loads, 148 3 g bump, 14
Page 536 and 537:
Index 513 Elk Test, 1 El-Nasher, 29
Page 538 and 539:
Index 515 generalised translational
Page 540 and 541:
Index 517 steer axis inclination, 1
show all

4569846498

Create successful ePaper yourself

Delete template?

Save as template?