Knowledge

Orientation (geometry)

Source 📝

38: 348: 336: 306: 750: 487: 317:. He imagined three reference frames that could rotate one around the other, and realized that by starting with a fixed reference frame and performing three rotations, he could get any other reference frame in the space (using two rotations to fix the vertical axis and another to fix the other two axes). The values of these three rotations are called 110:(or linear position). The position and orientation together fully describe how the object is placed in space. The above-mentioned imaginary rotation and translation may be thought to occur in any order, as the orientation of an object does not change when it translates, and its position does not change when it rotates. 467:, also called versors. They are equivalent to rotation matrices and rotation vectors. With respect to rotation vectors, they can be more easily converted to and from matrices. When used to represent orientations, rotation quaternions are typically called orientation quaternions or attitude quaternions. 373:
Based on this fact he introduced a vectorial way to describe any rotation, with a vector on the rotation axis and module equal to the value of the angle. Therefore, any orientation can be represented by a rotation vector (also called Euler vector) that leads to it from the reference frame. When used
203:). At least three independent values are needed to describe the orientation of this local frame. Three other values describe the position of a point on the object. All the points of the body change their position during a rotation except for those lying on the rotation axis. If the rigid body has 343:
These are three angles, also known as yaw, pitch and roll, Navigation angles and Cardan angles. Mathematically they constitute a set of six possibilities inside the twelve possible sets of Euler angles, the ordering being the one best used for describing the orientation of a vehicle such as an
498:, and consists of at least three coordinates. One scheme for orienting a rigid body is based upon body-axes rotation; successive rotations three times about the axes of the body's fixed reference frame, thereby establishing the body's 414:). The product of two rotation matrices is the composition of rotations. Therefore, as before, the orientation can be given as the rotation from the initial frame to achieve the frame that we want to describe. 101:
that is needed to move the object from a reference placement to its current placement. A rotation may not be enough to reach the current placement, in which case it may be necessary to add an imaginary
195:
are defined as the position and orientation, relative to the main reference frame, of another reference frame, which is fixed relative to the body, and hence translates and rotates with it (the body's
494:
The attitude of a rigid body is its orientation as described, for example, by the orientation of a frame fixed in the body relative to a fixed reference frame. The attitude is described by
403:
referred to as rotation matrices or direction cosine matrices. When used to represent an orientation, a rotation matrix is commonly called orientation matrix, or attitude matrix.
207:
not all orientations are distinguishable, except by observing how the orientation evolves in time from a known starting orientation. For example, the orientation in space of a
223:. Another example is the position of a point on the Earth, often described using the orientation of a line joining it with the Earth's center, measured using the two angles of 254:) is given by a single value: the angle through which it has rotated. There is only one degree of freedom and only one fixed point about which the rotation takes place. 370:). Therefore, the composition of the former three angles has to be equal to only one rotation, whose axis was complicated to calculate until matrices were developed. 238:
Further details about the mathematical methods to represent the orientation of rigid bodies and planes in three dimensions are given in the following sections.
291:
Several methods to describe orientations of a rigid body in three dimensions have been developed. They are summarized in the following sections.
754: 548: 286: 584: 780: 623: 603:...the attitude of a plane or a line — that is, its orientation in space — is fundamental to the description of structures. 366:
Euler also realized that the composition of two rotations is equivalent to a single rotation about a different fixed axis (
27:
This article is about the orientation or attitude of an object or a shape in a space. For the orientation of a space, see
17: 729: 697: 664: 635: 596: 418: 464: 458: 125: 770: 503: 378: 361: 266:
dimensions, specification of an orientation of an object that does not have any rotational symmetry requires
164: 121: 374:
to represent an orientation, the rotation vector is commonly called orientation vector, or attitude vector.
117: 775: 523: 367: 175: 113: 657:
Quaternions and Rotation Sequences: A Primer with Applications to Orbits, Aerospace, and Virtual Reality
399:
With the introduction of matrices, the Euler theorems were rewritten. The rotations were described by
528: 689: 533: 231:
can be described with two values as well, for instance by specifying the orientation of a line
224: 103: 46: 717: 652: 330: 558: 518: 160: 8: 385:
aligned with the rotation axis, and a separate value to indicate the angle (see figure).
204: 107: 682: 216: 171: 50: 725: 693: 660: 631: 592: 543: 400: 220: 129: 449:
to an object. The direction in which each vector points determines its orientation.
615: 553: 437: 430: 228: 86: 507: 440: 394: 344:
airplane. In aerospace engineering they are usually referred to as Euler angles.
208: 137: 94: 82: 314: 247: 232: 145: 141: 764: 446: 157: 149: 28: 116:
shows that in three dimensions any orientation can be reached with a single
619: 563: 499: 318: 300: 251: 212: 133: 538: 407: 382: 153: 481: 411: 192: 90: 42: 120:. This gives one common way of representing the orientation using an 422: 98: 58: 630:. American Institute of Aeronautics and Astronautics. p. 71. 347: 582: 309:
Euler angles, one of the possible ways to describe an orientation
37: 715: 749: 614: 335: 313:
The first attempt to represent an orientation is attributed to
688:. American Institute of Aeronautics and Astronautics. p.  305: 490:
The orientation of a rigid body is determined by three angles
97:
it occupies. More specifically, it refers to the imaginary
410:
of a rotation matrix (a rotation matrix has a unique real
486: 445:. Orientation may be visualized by attaching a basis of 93:– is part of the description of how it is placed in the 339:
Tait–Bryan angles. Other way for describing orientation
219:
can be specified with only two values, for example two
235:
to that plane, or by using the strike and dip angles.
191:
In general the position and orientation in space of a
681: 351:A rotation represented by an Euler axis and angle. 170:Typically, the orientation is given relative to a 280: 762: 508:incremental deviations from the nominal attitude 250:the orientation of any object (line, vector, or 650: 181: 381:, describes a rotation or orientation using a 583:Robert J. Twiss; Eldridge M. Moores (1992). 722:Modelling and Control of Robot Manipulators 716:Lorenzo Sciavicco; Bruno Siciliano (2000). 653:"Figure 4.7: Aircraft Euler angle sequence" 463:Another way to describe rotations is using 659:. Princeton University Press. p. 85. 156:may also be used to represent an object's 452: 709: 679: 485: 406:The above-mentioned Euler vector is the 346: 334: 304: 36: 591:(2nd ed.). Macmillan. p. 11. 549:Rotation formalisms in three dimensions 287:Rotation formalisms in three dimensions 14: 763: 724:(2nd ed.). Springer. p. 32. 680:Bong Wie (1998). "§5.2 Euler angles". 644: 257: 628:Analytical Mechanics of Space Systems 608: 576: 506:, although these terms also refer to 388: 355: 331:Euler angles § Tait–Bryan angles 585:"§2.1 The orientation of structures" 324: 124:. Other widely used methods include 186: 24: 684:Space Vehicle Dynamics and Control 673: 227:. Likewise, the orientation of a 25: 792: 742: 470: 241: 34:Notion of pointing in a direction 748: 704:Euler angle rigid body attitude. 459:Quaternions and spatial rotation 294: 140:. More specialist uses include 718:"§2.4.2 Roll–pitch–yaw angles" 281:Rigid body in three dimensions 13: 1: 569: 475: 781:Rotation in three dimensions 182:Mathematical representations 118:rotation around a fixed axis 7: 512: 176:Cartesian coordinate system 10: 797: 479: 456: 392: 359: 328: 298: 284: 41:Changing orientation of a 26: 755:Orientation (mathematics) 379:axis–angle representation 377:A similar method, called 362:Axis–angle representation 174:, usually specified by a 122:axis–angle representation 81:of an object – such as a 651:Jack B. Kuipers (2002). 502:. Another is based upon 368:Euler's rotation theorem 114:Euler's rotation theorem 624:"Rigid body kinematics" 529:Body relative direction 201:local coordinate system 106:to change the object's 771:Orientation (geometry) 534:Directional statistics 491: 453:Orientation quaternion 429:-dimensional space is 352: 340: 310: 225:longitude and latitude 54: 489: 350: 338: 308: 197:local reference frame 152:on maps and signs. A 40: 757:at Wikimedia Commons 559:Terms of orientation 519:Angular displacement 496:attitude coordinates 465:rotation quaternions 277:independent values. 167:between two points. 144:in crystallography, 126:rotation quaternions 504:roll, pitch and yaw 419:configuration space 401:orthogonal matrices 356:Orientation vector 258:Multiple dimensions 205:rotational symmetry 18:Attitude (geometry) 776:Euclidean geometry 589:Structural Geology 492: 389:Orientation matrix 353: 341: 311: 172:frame of reference 165:relative direction 55: 753:Media related to 544:Plane of rotation 325:Tait–Bryan angles 221:direction cosines 138:rotation matrices 16:(Redirected from 788: 752: 736: 735: 713: 707: 706: 687: 677: 671: 670: 648: 642: 641: 616:Hanspeter Schaub 612: 606: 605: 580: 554:Signed direction 524:Attitude control 276: 265: 187:Three dimensions 79:angular position 21: 796: 795: 791: 790: 789: 787: 786: 785: 761: 760: 745: 740: 739: 732: 714: 710: 700: 678: 674: 667: 649: 645: 638: 620:John L. Junkins 613: 609: 599: 581: 577: 572: 515: 484: 478: 473: 461: 455: 447:tangent vectors 397: 395:Rotation matrix 391: 364: 358: 333: 327: 303: 297: 289: 283: 267: 263: 262:When there are 260: 244: 189: 184: 148:in geology and 53:attached to it. 51:reference frame 45:is the same as 35: 32: 23: 22: 15: 12: 11: 5: 794: 784: 783: 778: 773: 759: 758: 744: 743:External links 741: 738: 737: 730: 708: 698: 672: 665: 643: 636: 607: 597: 574: 573: 571: 568: 567: 566: 561: 556: 551: 546: 541: 536: 531: 526: 521: 514: 511: 480:Main article: 477: 474: 472: 471:Usage examples 469: 457:Main article: 454: 451: 393:Main article: 390: 387: 360:Main article: 357: 354: 329:Main article: 326: 323: 315:Leonhard Euler 299:Main article: 296: 293: 285:Main article: 282: 279: 259: 256: 248:two dimensions 243: 242:Two dimensions 240: 188: 185: 183: 180: 146:strike and dip 142:Miller indices 49:the axes of a 33: 9: 6: 4: 3: 2: 793: 782: 779: 777: 774: 772: 769: 768: 766: 756: 751: 747: 746: 733: 731:1-85233-221-2 727: 723: 719: 712: 705: 701: 699:1-56347-261-9 695: 691: 686: 685: 676: 668: 666:0-691-10298-8 662: 658: 654: 647: 639: 637:1-56347-563-4 633: 629: 625: 621: 617: 611: 604: 600: 598:0-7167-2252-6 594: 590: 586: 579: 575: 565: 562: 560: 557: 555: 552: 550: 547: 545: 542: 540: 539:Oriented area 537: 535: 532: 530: 527: 525: 522: 520: 517: 516: 510: 509: 505: 501: 497: 488: 483: 468: 466: 460: 450: 448: 444: 443: 439: 436: 434: 428: 424: 420: 415: 413: 409: 404: 402: 396: 386: 384: 380: 375: 371: 369: 363: 349: 345: 337: 332: 322: 320: 316: 307: 302: 292: 288: 278: 274: 270: 255: 253: 249: 239: 236: 234: 230: 226: 222: 218: 214: 210: 206: 202: 198: 194: 179: 177: 173: 168: 166: 162: 159: 158:normal vector 155: 151: 147: 143: 139: 135: 131: 127: 123: 119: 115: 111: 109: 105: 100: 96: 92: 88: 84: 80: 76: 72: 68: 64: 60: 52: 48: 44: 39: 30: 29:Orientability 19: 721: 711: 703: 683: 675: 656: 646: 627: 610: 602: 588: 578: 564:Triad method 500:Euler angles 495: 493: 462: 441: 432: 426: 416: 405: 398: 376: 372: 365: 342: 319:Euler angles 312: 301:Euler angles 295:Euler angles 290: 272: 268: 261: 252:plane figure 245: 237: 213:line segment 200: 196: 190: 169: 134:Euler angles 112: 78: 74: 70: 66: 62: 56: 423:symmetrical 408:eigenvector 383:unit vector 154:unit vector 104:translation 63:orientation 765:Categories 570:References 482:Rigid body 476:Rigid body 425:object in 412:eigenvalue 193:rigid body 91:rigid body 43:rigid body 421:of a non- 161:direction 75:direction 622:(2003). 513:See also 275:− 1) / 2 108:position 99:rotation 67:attitude 59:geometry 47:rotating 163:or the 71:bearing 728:  696:  663:  634:  595:  233:normal 217:vector 130:rotors 61:, the 229:plane 215:, or 199:, or 150:grade 136:, or 95:space 87:plane 77:, or 726:ISBN 694:ISBN 661:ISBN 632:ISBN 593:ISBN 417:The 209:line 83:line 690:310 431:SO( 246:In 89:or 57:In 767:: 720:. 702:. 692:. 655:. 626:. 618:; 601:. 587:. 321:. 211:, 178:. 132:, 128:, 85:, 73:, 69:, 65:, 734:. 669:. 640:. 442:R 438:× 435:) 433:n 427:n 273:d 271:( 269:d 264:d 31:. 20:)

Index

Attitude (geometry)
Orientability

rigid body
rotating
reference frame
geometry
line
plane
rigid body
space
rotation
translation
position
Euler's rotation theorem
rotation around a fixed axis
axis–angle representation
rotation quaternions
rotors
Euler angles
rotation matrices
Miller indices
strike and dip
grade
unit vector
normal vector
direction
relative direction
frame of reference
Cartesian coordinate system

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑