Gait Tracking Control of Quadruped Robot Using Differential Evolution Based Structure Specified Mixed Sensitivity <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.3443pt" id="M1" height="15.7437pt" version="1.1" viewBox="-0.0657574 -11.3994 26.9666 15.7437" width="26.9666pt"><g transform="matrix(.017,0,0,-0.017,0,0)"><path id="g113-73" d="M828 650H570L564 622C646 614 650 609 634 524L604 366H253L281 524C296 608 308 615 382 622L388 650H132L126 622C211 615 214 609 198 524L121 122C106 42 102 35 23 28L17 0H276L282 28C196 35 191 40 206 122L243 324H597L559 123C544 42 537 35 452 28L446 0H710L716 28C632 35 628 43 643 122L719 524C735 610 741 615 822 622L828 650Z"/></g><g transform="matrix(.012,0,0,-0.012,13.299,4.134)"><path id="g14-30" d="M1034 231C1034 352 945 457 803 457C686 457 615 395 553 303C486 406 399 457 271 457C159 457 30 375 30 212C30 102 108 -12 267 -12C382 -12 450 51 509 142C577 37 668 -12 799 -12C917 -12 1034 68 1034 231ZM483 186C432 104 369 32 277 32C215 32 175 127 175 249C175 362 216 414 257 414C348 414 423 291 483 186ZM887 200C887 56 847 32 809 32C715 32 640 154 579 260C631 342 696 414 789 414C852 414 887 338 887 200Z"/></g></svg> Robust Control

<div>Control block diagram of the quadruped robot, where <svg height="11.927pt" id="M38" style="vertical-align:-3.291101pt" version="1.1" viewbox="-0.0498162 -8.6359 12.4304 11.927" width="12.4304pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M600 480C600 590 528 650 384 650H143L137 622C222 614 225 607 210 531L130 127C113 41 106 36 23 28L17 0H294L300 28C204 36 195 42 212 127L243 284L314 263C327 263 339 263 352 264C465 271 600 337 600 480ZM508 481C508 351 402 304 329 304C289 304 265 311 250 317L295 559C302 594 310 606 323 611C335 616 350 619 367 619C455 619 508 573 508 481Z" id="g113-81"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="617" vert-adv-y="617"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,6.656,3.132)"><path d="M538 684C542 703 539 710 529 710C512 710 455 682 363 674L361 644H396C444 644 448 642 438 594L405 438C373 450 347 451 336 451C288 451 200 416 147 374C69 312 24 207 24 113C24 29 60 -12 94 -12C126 -12 156 4 196 30C231 53 296 100 346 166H348L328 81C311 10 325 -12 348 -12C380 -12 450 24 512 98L495 125C466 97 431 70 417 70C408 70 408 80 411 98L538 684ZM390 373L361 240C336 196 210 56 145 56C132 56 113 73 113 131C113 216 156 338 220 379C243 394 266 402 303 402C331 402 375 388 390 373Z" id="g50-101"></path><glyph.data ascent="3443" descent="-2856" horiz-adv-x="564" vert-adv-y="564"></glyph.data></g></svg>, <svg height="12.5794pt" id="M39" style="vertical-align:-3.29107pt" version="1.1" viewbox="-0.0498162 -9.28833 11.9215 12.5794" width="11.9215pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z" id="g113-230"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="498" vert-adv-y="498"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,6.149,3.132)"><path d="M538 684C542 703 539 710 529 710C512 710 455 682 363 674L361 644H396C444 644 448 642 438 594L405 438C373 450 347 451 336 451C288 451 200 416 147 374C69 312 24 207 24 113C24 29 60 -12 94 -12C126 -12 156 4 196 30C231 53 296 100 346 166H348L328 81C311 10 325 -12 348 -12C380 -12 450 24 512 98L495 125C466 97 431 70 417 70C408 70 408 80 411 98L538 684ZM390 373L361 240C336 196 210 56 145 56C132 56 113 73 113 131C113 216 156 338 220 379C243 394 266 402 303 402C331 402 375 388 390 373Z" id="g50-101"></path><glyph.data ascent="3443" descent="-2856" horiz-adv-x="564" vert-adv-y="564"></glyph.data></g></svg>, and <svg height="12.584pt" id="M40" style="vertical-align:-3.29567pt" version="1.1" viewbox="-0.0498162 -9.28833 19.0917 12.584" width="19.0917pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z" id="g113-230"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="498" vert-adv-y="498"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,6.149,3.132)"><path d="M262 451C169 451 38 375 38 210C38 98 121 -12 261 -12C360 -12 481 64 481 227C481 351 386 451 262 451ZM249 414C337 414 385 320 385 204C385 70 333 25 272 25C189 25 134 117 134 241C134 355 189 414 249 414Z" id="g58-109"></path><glyph.data ascent="1007" descent="-369" horiz-adv-x="519" vert-adv-y="519"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,10.771,3.132)"><path d="M527 54L498 55C459 56 451 63 451 114V445C436 442 413 438 384 435C353 432 318 430 291 429V402L328 396C361 390 370 387 370 331V101C336 70 300 54 262 54C217 54 173 78 173 166V300C173 361 173 412 176 445C160 442 132 438 105 434C77 431 52 430 29 429V402L59 395C83 390 92 385 92 331V141C92 30 150 -12 218 -12C246 -12 266 -4 295 13C324 29 346 47 370 64V-6L376 -12C396 -7 421 1 448 8C476 15 504 21 527 24V54Z" id="g58-115"></path><glyph.data ascent="1007" descent="-369" horiz-adv-x="541" vert-adv-y="541"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,15.585,3.132)"><path d="M303 37L293 66C280 59 256 49 231 49S173 63 173 143V396H281C294 404 298 428 287 439H173V575L158 577L92 509V439H46L17 408L22 396H92V107C92 27 128 -12 192 -12C203 -12 218 -9 237 2L303 37Z" id="g58-114"></path><glyph.data ascent="1007" descent="-369" horiz-adv-x="312" vert-adv-y="312"></glyph.data></g></svg>, respectively, denote foot position reference, joint angle reference, and actual joint angles.</div>

Journal of Control Science and Engineering

fig3

Figure 3

Figure 3: Gait Tracking Control of Quadruped Robot Using Differential Evolution Based Structure Specified Mixed Sensitivity <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.3443pt" id="M1" height="15.7437pt" version="1.1" viewBox="-0.0657574 -11.3994 26.9666 15.7437" width="26.9666pt"><g transform="matrix(.017,0,0,-0.017,0,0)"><path id="g113-73" d="M828 650H570L564 622C646 614 650 609 634 524L604 366H253L281 524C296 608 308 615 382 622L388 650H132L126 622C211 615 214 609 198 524L121 122C106 42 102 35 23 28L17 0H276L282 28C196 35 191 40 206 122L243 324H597L559 123C544 42 537 35 452 28L446 0H710L716 28C632 35 628 43 643 122L719 524C735 610 741 615 822 622L828 650Z"/></g><g transform="matrix(.012,0,0,-0.012,13.299,4.134)"><path id="g14-30" d="M1034 231C1034 352 945 457 803 457C686 457 615 395 553 303C486 406 399 457 271 457C159 457 30 375 30 212C30 102 108 -12 267 -12C382 -12 450 51 509 142C577 37 668 -12 799 -12C917 -12 1034 68 1034 231ZM483 186C432 104 369 32 277 32C215 32 175 127 175 249C175 362 216 414 257 414C348 414 423 291 483 186ZM887 200C887 56 847 32 809 32C715 32 640 154 579 260C631 342 696 414 789 414C852 414 887 338 887 200Z"/></g></svg> Robust Control 

Journal of Control Science and Engineering

Gait Tracking Control of Quadruped Robot Using Differential Evolution Based Structure Specified Mixed Sensitivity Robust Control

Figure 3