Knowledge (XXG)

PLEXIL

Source 📝

211:
that implements PLEXIL and can be interfaced (using a provided software framework) with external systems to be controlled and/or queried. PLEXIL has been used to demonstrate automation technologies targeted at future NASA space missions.
246:. A plan is a tree divided in nodes close to the root (high level nodes) and leaf nodes that represent primitive actions such as variable assignments or the sending of commands to the external system. 577: 155: 190: 182: 111: 27: 552: 198: 582: 239:
that drive the execution of the node and another set which specifies what the node accomplishes after execution.
236: 208: 67: 426: 430: 205: 483: 547: 167: 22: 261:: List nodes are the internal nodes in a plan. These nodes have child nodes that can be of any type. 147: 279::accesses external functions that perform computations, but do not alter the state of the system. 562: 90: 74: 220: 34: 377: : This is true when all child nodes are either in node state waiting or finished. 232: 122: 571: 458: 535: 530: 186: 525: 557: 216: 63: 59: 54: 171: 151: 401: : The (single) parent of the node transitions to node state executing. 365: : The invariant condition of any ancestor changes to false or unknown. 177:
PLEXIL is used in automation technologies such as the NASA K10 rover, Mars
407: : the repeat condition changes from unknown to either true or false. 395: : The (single) parent of the node transitions to node state waiting. 508: 118: 285:: Provides information to the planning and decision support interface. 83: 459:"Bibliography of PLEXIL-related publications, organized by category" 231:
The fundamental programming unit of PLEXIL is the Node. A node is a
197:, Autonomy Operating System (AOS) and procedure automation for the 353: : Invariant condition changes from true to false or unknown. 347: : The start condition changes from unknown or false to true. 194: 79: 341: : The skip condition changes from unknown or false to true. 103: 254:
As of September 2008 NASA has implemented seven types of nodes.
39: 297:: Nodes that contain attributes and do not perform any actions. 273:: Performs a local operation and assigns a value to a variable. 371: : The end condition of any ancestor changes to true. 383: : When the abort for a command action is completed. 215:
The binaries and documentation are widely available as
429:; Simmons, Reid; Tso, Kam; Verma, Vandi (April 2006). 291:
nodes: This nodes invoke nodes in an external library.
267:: These nodes issue commands that drive the system. 109: 99: 89: 73: 53: 45: 33: 21: 389: : The abort of a function call is completed. 187:Deep Space Habitat and Habitat Demonstration Unit 242:A hierarchical composition of nodes is called a 431:"Plan Execution Interchange Language (PLEXIL)" 306:Each node can be in only one state. They are: 8: 16: 235:formed of two primary components: a set of 154:, created and currently in development by 15: 191:Edison Demonstration of Smallsat Networks 417: 359: : End condition changes to true. 578:Domain-specific programming languages 7: 509:"PLEXIL (Plan execution software)" 375:All_children_waiting_or_finished T 14: 484:"Main page: NASA applications" 104:http://plexil.sourceforge.net/ 1: 438:NASA Technical Reports Server 425:Estlin, Tara; Jonsson, Ari; 553:Spacecraft command language 204:The PLEXIL Executive is an 199:International Space Station 170:for representing plans for 599: 363:Ancestor_inv_condition F/U 387:Function_abort_complete T 117: 381:Command_abort_complete T 369:Ancestor_end_condition T 351:InvariantCondition F/U 536:PLEXIL at SourceForge 548:Programming Language 168:programming language 405:RepeatCondition T/F 277:Function call nodes 46:First appeared 18: 488:PLEXIL sourceforge 399:Parent_executing T 333:Nodes transitions: 583:Robotics software 563:Space exploration 463:Plexil souceforge 427:Pasareanu, Corina 219:open source from 128: 127: 55:Typing discipline 590: 513: 512: 505: 499: 498: 496: 494: 480: 474: 473: 471: 469: 455: 449: 448: 446: 444: 435: 422: 393:Parent_waiting T 345:StartCondition T 271:Assignment nodes 183:percussion drill 35:Designed by 19: 598: 597: 593: 592: 591: 589: 588: 587: 568: 567: 544: 522: 517: 516: 507: 506: 502: 492: 490: 482: 481: 477: 467: 465: 457: 456: 452: 442: 440: 433: 424: 423: 419: 414: 339:SkipCondition T 322:Iteration_Ended 229: 221:SourceForge.net 164: 150:technology for 146:anguage) is an 112:implementations 12: 11: 5: 596: 594: 586: 585: 580: 570: 569: 566: 565: 560: 555: 550: 543: 540: 539: 538: 533: 528: 526:PLEXIL at NASA 521: 520:External links 518: 515: 514: 500: 475: 450: 416: 415: 413: 410: 409: 408: 402: 396: 390: 384: 378: 372: 366: 360: 357:EndCondition T 354: 348: 342: 330: 329: 326: 323: 320: 317: 314: 311: 299: 298: 292: 286: 280: 274: 268: 262: 233:data structure 228: 225: 163: 160: 126: 125: 123:Space missions 115: 114: 107: 106: 101: 97: 96: 93: 87: 86: 77: 71: 70: 57: 51: 50: 47: 43: 42: 37: 31: 30: 28:Multi-paradigm 25: 13: 10: 9: 6: 4: 3: 2: 595: 584: 581: 579: 576: 575: 573: 564: 561: 559: 556: 554: 551: 549: 546: 545: 541: 537: 534: 532: 531:PLEXIL Manual 529: 527: 524: 523: 519: 510: 504: 501: 489: 485: 479: 476: 464: 460: 454: 451: 439: 432: 428: 421: 418: 411: 406: 403: 400: 397: 394: 391: 388: 385: 382: 379: 376: 373: 370: 367: 364: 361: 358: 355: 352: 349: 346: 343: 340: 337: 336: 335: 334: 327: 324: 321: 318: 315: 312: 309: 308: 307: 304: 303: 296: 293: 290: 287: 284: 281: 278: 275: 272: 269: 266: 265:Command nodes 263: 260: 257: 256: 255: 252: 251: 247: 245: 240: 238: 234: 226: 224: 222: 218: 213: 210: 207: 202: 200: 196: 192: 188: 184: 180: 175: 173: 169: 161: 159: 157: 153: 149: 145: 141: 137: 133: 124: 120: 116: 113: 108: 105: 102: 98: 94: 92: 88: 85: 81: 78: 76: 72: 69: 65: 61: 58: 56: 52: 48: 44: 41: 38: 36: 32: 29: 26: 24: 20: 503: 491:. Retrieved 487: 478: 466:. Retrieved 462: 453: 441:. Retrieved 437: 420: 404: 398: 392: 386: 380: 374: 368: 362: 356: 350: 344: 338: 332: 331: 305: 302:Node states: 301: 300: 294: 289:Library call 288: 283:Update nodes 282: 276: 270: 264: 258: 253: 249: 248: 243: 241: 230: 217:BSD licensed 214: 203: 178: 176: 166:PLEXIL is a 165: 143: 139: 135: 131: 129: 558:Cybernetics 295:Empty nodes 250:Node Types: 148:open source 142:nterchange 95:Open source 572:Categories 493:8 February 468:8 February 443:8 February 412:References 259:List nodes 237:conditions 172:automation 152:automation 68:nominative 319:Finishing 316:Executing 206:execution 179:Curiosity 542:See also 328:Finished 310:Inactive 181:rover's 162:Overview 138:ecution 130:PLEXIL ( 119:Robotics 23:Paradigm 325:Failing 313:Waiting 100:Website 91:License 209:engine 110:Major 84:Mac OS 64:unsafe 60:Static 17:PLEXIL 434:(PDF) 227:Nodes 195:LADEE 80:Linux 495:2019 470:2019 445:2019 244:plan 156:NASA 49:2005 40:NASA 134:an 574:: 486:. 461:. 436:. 223:. 201:. 193:, 189:, 185:, 174:. 158:. 136:Ex 132:Pl 121:, 82:, 75:OS 66:, 62:, 511:. 497:. 472:. 447:. 144:L 140:I

Index

Paradigm
Multi-paradigm
Designed by
NASA
Typing discipline
Static
unsafe
nominative
OS
Linux
Mac OS
License
http://plexil.sourceforge.net/
implementations
Robotics
Space missions
open source
automation
NASA
programming language
automation
percussion drill
Deep Space Habitat and Habitat Demonstration Unit
Edison Demonstration of Smallsat Networks
LADEE
International Space Station
execution
engine
BSD licensed
SourceForge.net

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