Hello Guest it is March 28, 2024, 03:20:18 PM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - joeaverage

Pages: « 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 »
1171
Mach4 General Discussion / Re: Hazardous Motion - Mach4 Software
« on: May 12, 2021, 04:29:24 PM »
Hi,

Quote
There is no such problem as a buffer "run on" with the SmoothStepper, because the buffer will be drained in less than 0.5 seconds

Correct, the jog moves are buffered in Mach NOT the ESS.

I say again, if the continuous jog issues more steps that can be consumed by the machine they get buffered and result in after-run.

Try an experiment, preferably with an MPG so you can vary the input step rate, and try it. With large jog steps you end up with after-run
and with small jog steps you do not. I did this exact experiment six years ago with that conclusion.

Craig


1172
General Mach Discussion / Re: Mach 3: Programmatic change to config
« on: May 11, 2021, 07:37:08 PM »
Hi,

Quote
Just with the SERVO encoder? That would be really interesting

Yes, that is exactly how my C axis works.

Craig

1173
Mach4 General Discussion / Re: Hazardous Motion - Mach4 Software
« on: May 11, 2021, 04:43:33 PM »
Hi,

Quote
Your suggestion is to reduce the jog increment down so few steps are in the buffer.  OK, the jog increment was 0.001" - I guess I could go to 0.0001" if you think that would help.  As far as knowing how many steps are in the buffer, how do I determine that?

That is a good question. In my case, as I use an MPG and do not use on-screen buttons, the solution and result are much plainer.

Lets say for example your machine has a max velocity of 1200mm/min. I choose this number as it suits my mini-mill which because of axis gearing
has relatively low G0 speeds.
1200/60= 20mm/sec.

If I set the max jog increment to 1mm, then if I spin the MPG (100 pulse/rev), at any greater than 20 clicks per second then movement is going to accumulate
in the buffer. Its entirely possible to spin the MPG at 1 rev, or 100 pulse per second, and thus I would have significant accumulated motion in the buffer.
If however I reduce the increment to 0.1mm then that same 100 pulse per second input results in 10mm/sec movement which is within my machine velocity
and therefore no accumulated movement.

The trick here is that I know how many steps per second I am applying by virtue of me spinning the MPG.

In your case using Mach's jog buttons is issuing a certain rate of steps....and exactly what they are I don't know. Lets guess and say that Mach is issuing 1000 pulses
per second, then at 0.1mm jog increment that would indicate a movement of 100mm/sec which exceeds my machine velocity and therefore get motion
accumulation. If I selected a jog increment of 0.01mm then the same 1000 pulse/sec input would result in 10mm/sec movement which is suitably within my machine limits.

I'm not sure off-hand how Mach determines the pulse rate. On the jog screen there is a slider at the bottom which is a percentage of max, whatever max is. Using that slider
you can slow the pulse rate down until you approach the balance point necessary to avoid accumulated motion.

I'm hoping that smurph sees this post and he will surely know how to set the rate. My guess is that once you make an appropriate setting you will then never touch it
again for the life of the machine. Such has been the case with my max jog increment, once I found the 'sweet spot' of 0.1mm it gets left there for months at a time.
I will sometimes drop down to 0.01mm if I have a fine touch off to complete, but even that does not happen that often.

Craig

1174
Mach4 General Discussion / Re: Hazardous Motion - Mach4 Software
« on: May 11, 2021, 03:41:52 PM »
Hi,

Quote
Thanks for your response.  It does make sense that an unemptied buffer could cause the problem, but I would call that a bug.  If the expectation is that jogging will stop when the button is released (I'm using a screen button not an MPG) then that's what should happen and the buffer should be flushed.  Any unexpected motion is cause for serious concern.  There should be no "catches you by surprise" when dealing with machine motion.

BS. Mach is doing EXACTLY what its supposed to do, if you issue 211 pulses of 1mm per pulse then it will move 211mm. That a number of those steps are
'in the buffer' and you can't visualize where that 211mm movement is going to end up is your problem......not Machs, it just going to the 211mm mark as
you requested.

When I first encountered this problem six years ago I too thought it a fault, and the hundreds of people since then that have posted about this
in the years since, all imagine its a Mach bug. ITS NOT!!!! If I tell Mach to move to a BS location, it goes there and crashes, its because I told it to go
there, its not up to Mach to try to anticipate my BS mistake.

Reduce the jog increment down to the situation that very few if any steps end up in the buffer and you'll never have the problem again.

Craig

1175
General Mach Discussion / Re: Mach 3: Programmatic change to config
« on: May 11, 2021, 03:26:21 PM »
Hi,

Quote
try to rigid tapping and in that case you trust the good closed loop system from the servo to don't keep up with Z and do not loose power. Is it correct?

Yes, the closed loop applies to the servo and servo drive. You signal the drive where you want the servo to be and the servo/servo drive takes itself
there. In some respects its like an open loop stepper, you signal a certain number of steps in a given direction and the stepper drive drives
the stepper to that location....assuming no loss of steps. A servo has feedback so that it is much more certain of arriving at the commanded location,
and if it can't for any reason it will fault 'following error' and alarm out.

You could signal the drive, one pulse = one revolution, but it would be very coarse. All AC servos have the principle of electronic gearing.
It allows that you can signal the drive at one rate, say 1324 pulse per rev, but the servo encoder is 10,000 pulse per rev. Electronic gearing allows
very great flexibility in application of a servo.

Craig

1176
Mach4 General Discussion / Re: Hazardous Motion - Mach4 Software
« on: May 11, 2021, 01:29:15 AM »
Hi,
I believe the problem you are experiencing is after-run.

When in continuous jog mode Mach issues  a stream of jog steps at the current jog increment. If the machine can move 20mm/sec but the steps
are indicating a move of 30mm/sec then the extra steps get buffered. Thus even when the button is released and Mach stops issuing jog steps the
steps in the buffer still have to execute, and will carry on until the buffer is drained, ie after-run.

You might consider this is a bug, its not. Its is that your selected jog increments mean that the buffer can fill up.......and it catches you by surprise.
If you reduce your maximum jog increment down to a realistic amount the problem ceases to exist.

As an example I used to have my max jog step set at 1mm/step. If I spin the MPG fast the steps exceed the ability of my machine to execute them
immediately, and I would get after-run with the attendant surprise and consternation. I have since set my max jog step to 0.1mm/step. Now I can
spin the MPG as fast as I like and my machine executes all  those steps nearly instantly, the buffer never fills up and therefore no after-run.

Another way of saying it is that the maximum jog increment  and jog step rate should match the velocity of the machine and thereby avoid
accumulated steps in the motion buffer.

Craig

1177
General Mach Discussion / Re: Mach 3: Programmatic change to config
« on: May 10, 2021, 08:58:55 PM »
Hi,
yes you can drive an AC servo with either step/direction OR PWM. In most circumstances there is little in it.

If your controller is providing an analogue voltage , ie PMW output, the servo drive closes its speed loop on that input voltage, thus any
speed reduction by virtue of changing load will be corrected by the servo drive feedback.

If your controller is outputting step/direction then the drive, using the servo encoder, closes the feedback loop.

Both methods result in the speed being controlled by a feedback loop....ergo no difference. Given that the spindle in Mach3, and incidentally Mach4,
is natively PWM it is easier to apply PWM than step/direction, although either is possible.

Step/Direction input allows you to have position control for an indexing spindle for instance, or C axis control for rigid tapping. Quite frankly I think
trying to get Mach3 to do a Caxis properly is going to be trouble.

Quote
Spindle motor to C axis, just by using an Index input (1 per rev), but in that case I believe you trust on the inbuilt encoder spindle and it's power to don't slow down while threading or bye bye, something bad will happen since there is no real feedback on the spindle. Is this the case?

That is a misunderstanding, the servo encoder is an INPUT into the servo drive and it is COMPARED to the step/direction input and the drive attempts to reduce the
error. That IS FEEDBACK, and its fundemental to the way AC servos operate. Thus an AC servo is in feedback control at all times, its just that you, or rather Mach,
does not control the feedback loop, it is enacted entirely by the servo drive. Should the load be such that the servo cannot keep up then the drive will alarm out
and stop. The feedback enacted by a modern servo drive on a matching servo is superb, better I would say, than any general purpose feedback controller can ever
manage. The manufacturer of a servo knows EXACTLY the best way to control it and makes their drives to PERFECTLY match the servo. If you think you can program
a PID loop better than a servo manufacturer then this is the wrong place for you!

Quote
Regarding the UC300ETH, I have seen it has an analog port but does it mean that for instance it can create the 0-10V signal to drive a VFD without an additional board?

This is a misunderstanding also. A controller, be it an ESS OR a UC300 can produce a PWM output signal which is filtered by an A-to-D converter on the BoB to produce an
analogue 0-10V signal. What a UC300 has is an analog input channel. The UC300 measures an analog input, say a voltage from a potentiometer say, and convert that into
a digital number which can be read and manipulated by Mach.

Quote
. Then a Estop is automatically triggered and the changes are applied. I have also tried to trigger the Estop manually but that doesn't help, so there is some kind of refresh cycle that it's automatically elicited when you close the ports and pins tab. Do you know if it's possible to trigger the same refresh cycle with a VB command? Thanks

This is part of the way Mach3 works, any change to the profile results in an Estop and must be manually restarted. Mach4 on the other hand can programmatically change settings in the
profile, with or without a save cycle, and carry on running. Mach4  and its Lua coding language is VASTLY superior when it comes to doing this sort of tricky-dicky  customisations.

Craig

1178
General Mach Discussion / Re: Mach 3: Programmatic change to config
« on: May 10, 2021, 03:54:24 PM »
Hi,
the ESS has a larger and more powerful FPGA and so has a few features that the USS misses on.

You mention encoder threading and the ESS does that, but to my knowledge is supported in Mach4 only. You can use encoder
threading in Mach3 but it treats the encoder channel as a single pulse per rev input, that is to say, encoder threading offers no advantage
over index threading, at least in Mach3.

Related to encoder threading is spindle PID. When using an encoder and a conventional PWM spindle the PWM is adjusted to control
spindle speed with a PID loop. The loop has a low bandwidth velocity loop so cannot be used as a servo controller, but is quite an
improvement over the open loop situation. Note  this is a  feature that occurs in the Mach4 plugin only and to my knowledge there is
no plan by Warp9 to extend the Mach3 plugin to support spindle PID.

The USS does not have the noise immunity to do plasma, whereas the ESS supports hardware THC in both Mach3 and Mach4 plugins.

I have an AC servo as a spindle motor, and I can use it as a conventional PWM spindle OR a step/direction C axis for rigid tapping. I can
change back and forth programmatically with Mach4, whether the same programmatic switch can happen in Mach3  is doubtful, rather like
this multi-probe problem.

Overall I think the ESS is an advantage over the USS but you will not get the true benefits until you step up to Mach4.

The only feature that the UC300, aside from compatibility with UCCNC, is an analogue input that the ESS lacks.

Craig

1179
General Mach Discussion / Re: Mach 3: Programmatic change to config
« on: May 10, 2021, 07:30:26 AM »
Hi,
its not possible in Mach3, at least programmatically.

That leaves some sort of hardware switch, eminently possible but far from straight forward.

Craig

1180
General Mach Discussion / Re: Mach 3: Programmatic change to config
« on: May 09, 2021, 08:46:12 PM »
Hi,
Mach4 has up to four independent probe channels, G31.1, G31.2, G31.3 and G31.4.

Craig

Pages: « 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 »