src/modules/tools/zprobe/ZProbe.cpp

   1 /*
   2       This file is part of Smoothie (http://smoothieware.org/). The motion control part is heavily based on Grbl (https://github.com/simen/grbl).
   3       Smoothie is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
   4       Smoothie is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   5       You should have received a copy of the GNU General Public License along with Smoothie. If not, see <http://www.gnu.org/licenses/>.
   6 */
   7
   8 #include "ZProbe.h"
   9
  10 #include "Kernel.h"
  11 #include "BaseSolution.h"
  12 #include "Config.h"
  13 #include "Robot.h"
  14 #include "StepperMotor.h"
  15 #include "StreamOutputPool.h"
  16 #include "Gcode.h"
  17 #include "Conveyor.h"
  18 #include "Stepper.h"
  19 #include "checksumm.h"
  20 #include "ConfigValue.h"
  21 #include "SlowTicker.h"
  22 #include "Planner.h"
  23 #include "SerialMessage.h"
  24 #include "PublicDataRequest.h"
  25 #include "EndstopsPublicAccess.h"
  26 #include "PublicData.h"
  27 #include "LevelingStrategy.h"
  28 #include "StepTicker.h"
  29 #include "utils.h"
  30
  31 // strategies we know about
  32 #include "DeltaCalibrationStrategy.h"
  33 #include "ThreePointStrategy.h"
  34 #include "ZGridStrategy.h"
  35
  36 #define enable_checksum          CHECKSUM("enable")
  37 #define probe_pin_checksum       CHECKSUM("probe_pin")
  38 #define debounce_count_checksum  CHECKSUM("debounce_count")
  39 #define slow_feedrate_checksum   CHECKSUM("slow_feedrate")
  40 #define fast_feedrate_checksum   CHECKSUM("fast_feedrate")
  41 #define return_feedrate_checksum CHECKSUM("return_feedrate")
  42 #define probe_height_checksum    CHECKSUM("probe_height")
  43 #define gamma_max_checksum       CHECKSUM("gamma_max")
  44
  45 // from endstop section
  46 #define delta_homing_checksum    CHECKSUM("delta_homing")
  47
  48 #define X_AXIS 0
  49 #define Y_AXIS 1
  50 #define Z_AXIS 2
  51
  52 #define STEPPER THEKERNEL->robot->actuators
  53 #define STEPS_PER_MM(a) (STEPPER[a]->get_steps_per_mm())
  54 #define Z_STEPS_PER_MM STEPS_PER_MM(Z_AXIS)
  55
  56 #define abs(a) ((a<0) ? -a : a)
  57
  58 void ZProbe::on_module_loaded()
  59 {
  60     // if the module is disabled -> do nothing
  61     if(!THEKERNEL->config->value( zprobe_checksum, enable_checksum )->by_default(false)->as_bool()) {
  62         // as this module is not needed free up the resource
  63         delete this;
  64         return;
  65     }
  66
  67     // load settings
  68     this->on_config_reload(this);
  69     // register event-handlers
  70     register_for_event(ON_GCODE_RECEIVED);
  71
  72     THEKERNEL->step_ticker->register_acceleration_tick_handler([this](){acceleration_tick(); });
  73
  74     // we read the probe in this timer, currently only for G38 probes.
  75     probing= false;
  76     THEKERNEL->slow_ticker->attach(1000, this, &ZProbe::read_probe);
  77 }
  78
  79 void ZProbe::on_config_reload(void *argument)
  80 {
  81     this->pin.from_string( THEKERNEL->config->value(zprobe_checksum, probe_pin_checksum)->by_default("nc" )->as_string())->as_input();
  82     this->debounce_count = THEKERNEL->config->value(zprobe_checksum, debounce_count_checksum)->by_default(0  )->as_number();
  83
  84     // get strategies to load
  85     vector<uint16_t> modules;
  86     THEKERNEL->config->get_module_list( &modules, leveling_strategy_checksum);
  87     for( auto cs : modules ){
  88         if( THEKERNEL->config->value(leveling_strategy_checksum, cs, enable_checksum )->as_bool() ){
  89             bool found= false;
  90             // check with each known strategy and load it if it matches
  91             switch(cs) {
  92                 case delta_calibration_strategy_checksum:
  93                     this->strategies.push_back(new DeltaCalibrationStrategy(this));
  94                     found= true;
  95                     break;
  96
  97                 case three_point_leveling_strategy_checksum:
  98                     // NOTE this strategy is mutually exclusive with the delta calibration strategy
  99                     this->strategies.push_back(new ThreePointStrategy(this));
 100                     found= true;
 101                     break;
 102
 103                 case ZGrid_leveling_checksum:
 104                      this->strategies.push_back(new ZGridStrategy(this));
 105                      found= true;
 106                      break;
 107
 108                 // add other strategies here
 109                 //case zheight_map_strategy:
 110                 //     this->strategies.push_back(new ZHeightMapStrategy(this));
 111                 //     found= true;
 112                 //     break;
 113             }
 114             if(found) this->strategies.back()->handleConfig();
 115         }
 116     }
 117
 118     // need to know if we need to use delta kinematics for homing
 119     this->is_delta = THEKERNEL->config->value(delta_homing_checksum)->by_default(false)->as_bool();
 120
 121     // default for backwards compatibility add DeltaCalibrationStrategy if a delta
 122     // will be deprecated
 123     if(this->strategies.empty()) {
 124         if(this->is_delta) {
 125             this->strategies.push_back(new DeltaCalibrationStrategy(this));
 126             this->strategies.back()->handleConfig();
 127         }
 128     }
 129
 130     this->probe_height  = THEKERNEL->config->value(zprobe_checksum, probe_height_checksum)->by_default(5.0F)->as_number();
 131     this->slow_feedrate = THEKERNEL->config->value(zprobe_checksum, slow_feedrate_checksum)->by_default(5)->as_number(); // feedrate in mm/sec
 132     this->fast_feedrate = THEKERNEL->config->value(zprobe_checksum, fast_feedrate_checksum)->by_default(100)->as_number(); // feedrate in mm/sec
 133     this->return_feedrate = THEKERNEL->config->value(zprobe_checksum, return_feedrate_checksum)->by_default(0)->as_number(); // feedrate in mm/sec
 134     this->max_z         = THEKERNEL->config->value(gamma_max_checksum)->by_default(500)->as_number(); // maximum zprobe distance
 135 }
 136
 137 bool ZProbe::wait_for_probe(int& steps)
 138 {
 139     unsigned int debounce = 0;
 140     while(true) {
 141         THEKERNEL->call_event(ON_IDLE);
 142         if(THEKERNEL->is_halted()){
 143             // aborted by kill
 144             return false;
 145         }
 146
 147         // if no stepper is moving, moves are finished and there was no touch
 148         if( !STEPPER[Z_AXIS]->is_moving() && (!is_delta || (!STEPPER[Y_AXIS]->is_moving() && !STEPPER[Z_AXIS]->is_moving())) ) {
 149             return false;
 150         }
 151
 152         // if the touchprobe is active...
 153         if( this->pin.get() ) {
 154             //...increase debounce counter...
 155             if( debounce < debounce_count) {
 156                 // ...but only if the counter hasn't reached the max. value
 157                 debounce++;
 158             } else {
 159                 // ...otherwise stop the steppers, return its remaining steps
 160                 if(STEPPER[Z_AXIS]->is_moving()){
 161                     steps= STEPPER[Z_AXIS]->get_stepped();
 162                     STEPPER[Z_AXIS]->move(0, 0);
 163                 }
 164                 if(is_delta) {
 165                     for( int i = X_AXIS; i <= Y_AXIS; i++ ) {
 166                         if ( STEPPER[i]->is_moving() ) {
 167                             STEPPER[i]->move(0, 0);
 168                         }
 169                     }
 170                 }
 171                 return true;
 172             }
 173         } else {
 174             // The probe was not hit yet, reset debounce counter
 175             debounce = 0;
 176         }
 177     }
 178 }
 179
 180 // single probe with custom feedrate
 181 // returns boolean value indicating if probe was triggered
 182 bool ZProbe::run_probe_feed(int& steps, float feedrate, float max_dist)
 183 {
 184     // not a block move so disable the last tick setting
 185     for ( int c = X_AXIS; c <= Z_AXIS; c++ ) {
 186         STEPPER[c]->set_moved_last_block(false);
 187     }
 188
 189     // Enable the motors
 190     THEKERNEL->stepper->turn_enable_pins_on();
 191     this->current_feedrate = feedrate * Z_STEPS_PER_MM; // steps/sec
 192     float maxz= max_dist < 0 ? this->max_z*2 : max_dist;
 193
 194     // move Z down
 195     STEPPER[Z_AXIS]->move(true, maxz * Z_STEPS_PER_MM, 0); // always probes down, no more than 2*maxz
 196     if(this->is_delta) {
 197         // for delta need to move all three actuators
 198         STEPPER[X_AXIS]->move(true, maxz * STEPS_PER_MM(X_AXIS), 0);
 199         STEPPER[Y_AXIS]->move(true, maxz * STEPS_PER_MM(Y_AXIS), 0);
 200     }
 201
 202     // start acceleration processing
 203     this->running = true;
 204
 205     bool r = wait_for_probe(steps);
 206     this->running = false;
 207     STEPPER[X_AXIS]->move(0, 0);
 208     STEPPER[Y_AXIS]->move(0, 0);
 209     STEPPER[Z_AXIS]->move(0, 0);
 210     return r;
 211 }
 212
 213 // single probe with either fast or slow feedrate
 214 // returns boolean value indicating if probe was triggered
 215 bool ZProbe::run_probe(int& steps, bool fast)
 216 {
 217     float feedrate = (fast ? this->fast_feedrate : this->slow_feedrate);
 218     return run_probe_feed(steps, feedrate);
 219 }
 220
 221 bool ZProbe::return_probe(int steps)
 222 {
 223     // move probe back to where it was
 224
 225     float fr;
 226     if(this->return_feedrate != 0) { // use return_feedrate if set
 227         fr = this->return_feedrate;
 228     } else {
 229         fr = this->slow_feedrate*2; // nominally twice slow feedrate
 230         if(fr > this->fast_feedrate) fr = this->fast_feedrate; // unless that is greater than fast feedrate
 231     }
 232
 233     this->current_feedrate = fr * Z_STEPS_PER_MM; // feedrate in steps/sec
 234     bool dir= steps < 0;
 235     steps= abs(steps);
 236
 237     STEPPER[Z_AXIS]->move(dir, steps, 0);
 238     if(this->is_delta) {
 239         STEPPER[X_AXIS]->move(dir, steps, 0);
 240         STEPPER[Y_AXIS]->move(dir, steps, 0);
 241     }
 242
 243     this->running = true;
 244     while(STEPPER[Z_AXIS]->is_moving() || (is_delta && (STEPPER[X_AXIS]->is_moving() || STEPPER[Y_AXIS]->is_moving())) ) {
 245         // wait for it to complete
 246         THEKERNEL->call_event(ON_IDLE);
 247          if(THEKERNEL->is_halted()){
 248             // aborted by kill
 249             break;
 250         }
 251     }
 252
 253     this->running = false;
 254     STEPPER[X_AXIS]->move(0, 0);
 255     STEPPER[Y_AXIS]->move(0, 0);
 256     STEPPER[Z_AXIS]->move(0, 0);
 257
 258     return true;
 259 }
 260
 261 bool ZProbe::doProbeAt(int &steps, float x, float y)
 262 {
 263     int s;
 264     // move to xy
 265     coordinated_move(x, y, NAN, getFastFeedrate());
 266     if(!run_probe(s)) return false;
 267
 268     // return to original Z
 269     return_probe(s);
 270     steps = s;
 271
 272     return true;
 273 }
 274
 275 float ZProbe::probeDistance(float x, float y)
 276 {
 277     int s;
 278     if(!doProbeAt(s, x, y)) return NAN;
 279     return zsteps_to_mm(s);
 280 }
 281
 282 void ZProbe::on_gcode_received(void *argument)
 283 {
 284     Gcode *gcode = static_cast<Gcode *>(argument);
 285
 286     if( gcode->has_g && gcode->g >= 29 && gcode->g <= 32) {
 287
 288         // make sure the probe is defined and not already triggered before moving motors
 289         if(!this->pin.connected()) {
 290             gcode->stream->printf("ZProbe not connected.\n");
 291             return;
 292         }
 293         if(this->pin.get()) {
 294             gcode->stream->printf("ZProbe triggered before move, aborting command.\n");
 295             return;
 296         }
 297
 298         if( gcode->g == 30 ) { // simple Z probe
 299             // NOTE currently this will not work for rotary deltas, use G38.2/3 Z instead
 300             // first wait for an empty queue i.e. no moves left
 301             THEKERNEL->conveyor->wait_for_empty_queue();
 302
 303             int steps;
 304             bool probe_result;
 305             if(gcode->has_letter('F')) {
 306                 probe_result = run_probe_feed(steps, gcode->get_value('F') / 60);
 307             } else {
 308                 probe_result = run_probe(steps);
 309             }
 310
 311             if(probe_result) {
 312                 gcode->stream->printf("Z:%1.4f C:%d\n", zsteps_to_mm(steps), steps);
 313                 // move back to where it started, unless a Z is specified
 314                 if(gcode->has_letter('Z')) {
 315                     // set Z to the specified value, and leave probe where it is
 316                     THEKERNEL->robot->reset_axis_position(gcode->get_value('Z'), Z_AXIS);
 317                 } else {
 318                     return_probe(steps);
 319                 }
 320             } else {
 321                 gcode->stream->printf("ZProbe not triggered\n");
 322             }
 323
 324         } else {
 325             if(!gcode->has_letter('P')) {
 326                 // find the first strategy to handle the gcode
 327                 for(auto s : strategies){
 328                     if(s->handleGcode(gcode)) {
 329                         return;
 330                     }
 331                 }
 332                 gcode->stream->printf("No strategy found to handle G%d\n", gcode->g);
 333
 334             }else{
 335                 // P paramater selects which strategy to send the code to
 336                 // they are loaded in the order they are defined in config, 0 being the first, 1 being the second and so on.
 337                 uint16_t i= gcode->get_value('P');
 338                 if(i < strategies.size()) {
 339                     if(!strategies[i]->handleGcode(gcode)){
 340                         gcode->stream->printf("strategy #%d did not handle G%d\n", i, gcode->g);
 341                     }
 342                     return;
 343
 344                 }else{
 345                     gcode->stream->printf("strategy #%d is not loaded\n", i);
 346                 }
 347             }
 348         }
 349
 350     } else if(gcode->has_g && gcode->g == 38 ) { // G38.2 Straight Probe with error, G38.3 straight probe without error
 351         // linuxcnc/grbl style probe http://www.linuxcnc.org/docs/2.5/html/gcode/gcode.html#sec:G38-probe
 352         if(gcode->subcode != 2 && gcode->subcode != 3) {
 353             gcode->stream->printf("error:Only G38.2 and G38.3 are supported\n");
 354             return;
 355         }
 356
 357         // make sure the probe is defined and not already triggered before moving motors
 358         if(!this->pin.connected()) {
 359             gcode->stream->printf("error:ZProbe not connected.\n");
 360             return;
 361         }
 362
 363         if(this->pin.get()) {
 364             gcode->stream->printf("error:ZProbe triggered before move, aborting command.\n");
 365             return;
 366         }
 367
 368         // first wait for an empty queue i.e. no moves left
 369         THEKERNEL->conveyor->wait_for_empty_queue();
 370
 371         // turn off any compensation transform
 372         auto savect= THEKERNEL->robot->compensationTransform;
 373         THEKERNEL->robot->compensationTransform= nullptr;
 374
 375         if(gcode->has_letter('X')) {
 376             // probe in the X axis
 377             probe_XYZ(gcode, X_AXIS);
 378
 379         }else if(gcode->has_letter('Y')) {
 380             // probe in the Y axis
 381             probe_XYZ(gcode, Y_AXIS);
 382
 383         }else if(gcode->has_letter('Z')) {
 384             // probe in the Z axis
 385             probe_XYZ(gcode, Z_AXIS);
 386
 387         }else{
 388             gcode->stream->printf("error:at least one of X Y or Z must be specified\n");
 389         }
 390
 391         // restore compensationTransform
 392         THEKERNEL->robot->compensationTransform= savect;
 393
 394         return;
 395
 396     } else if(gcode->has_m) {
 397         // M code processing here
 398         int c;
 399         switch (gcode->m) {
 400             case 119:
 401                 c = this->pin.get();
 402                 gcode->stream->printf(" Probe: %d", c);
 403                 gcode->add_nl = true;
 404                 break;
 405
 406             case 670:
 407                 if (gcode->has_letter('S')) this->slow_feedrate = gcode->get_value('S');
 408                 if (gcode->has_letter('K')) this->fast_feedrate = gcode->get_value('K');
 409                 if (gcode->has_letter('R')) this->return_feedrate = gcode->get_value('R');
 410                 if (gcode->has_letter('Z')) this->max_z = gcode->get_value('Z');
 411                 if (gcode->has_letter('H')) this->probe_height = gcode->get_value('H');
 412                 break;
 413
 414             case 500: // save settings
 415             case 503: // print settings
 416                 gcode->stream->printf(";Probe feedrates Slow/fast(K)/Return (mm/sec) max_z (mm) height (mm):\nM670 S%1.2f K%1.2f R%1.2f Z%1.2f H%1.2f\n",
 417                     this->slow_feedrate, this->fast_feedrate, this->return_feedrate, this->max_z, this->probe_height);
 418
 419                 // fall through is intended so leveling strategies can handle m-codes too
 420
 421             default:
 422                 for(auto s : strategies){
 423                     if(s->handleGcode(gcode)) {
 424                         return;
 425                     }
 426                 }
 427         }
 428     }
 429 }
 430
 431 uint32_t ZProbe::read_probe(uint32_t dummy)
 432 {
 433     if(!probing || probe_detected) return 0;
 434
 435     // TODO add debounce/noise filter
 436     if(this->pin.get()) {
 437         probe_detected= true;
 438         // now tell all the stepper_motors to stop
 439         for(auto &a : THEKERNEL->robot->actuators) a->force_finish_move();
 440     }
 441     return 0;
 442 }
 443
 444 // special way to probe in the X or Y or Z direction using planned moves, should work with any kinematics
 445 void ZProbe::probe_XYZ(Gcode *gcode, int axis)
 446 {
 447     // enable the probe checking in the timer
 448     probing= true;
 449     probe_detected= false;
 450     THEKERNEL->robot->disable_segmentation= true; // we must disable segmentation as this won't work with it enabled (beware on deltas probing in X or Y)
 451
 452     // get probe feedrate if specified
 453     float rate = (gcode->has_letter('F')) ? gcode->get_value('F')*60 : this->slow_feedrate;
 454
 455     // do a regular move which will stop as soon as the probe is triggered, or the distance is reached
 456     switch(axis) {
 457         case X_AXIS: coordinated_move(gcode->get_value('X'), 0, 0, rate, true); break;
 458         case Y_AXIS: coordinated_move(0, gcode->get_value('Y'), 0, rate, true); break;
 459         case Z_AXIS: coordinated_move(0, 0, gcode->get_value('Z'), rate, true); break;
 460     }
 461
 462     // coordinated_move returns when the move is finished
 463
 464     // disable probe checking
 465     probing= false;
 466     THEKERNEL->robot->disable_segmentation= false;
 467
 468     float pos[3];
 469     {
 470         // get the current position
 471         ActuatorCoordinates current_position{
 472             THEKERNEL->robot->actuators[X_AXIS]->get_current_position(),
 473             THEKERNEL->robot->actuators[Y_AXIS]->get_current_position(),
 474             THEKERNEL->robot->actuators[Z_AXIS]->get_current_position()
 475         };
 476
 477         // get machine position from the actuator position using FK
 478         THEKERNEL->robot->arm_solution->actuator_to_cartesian(current_position, pos);
 479     }
 480
 481     uint8_t probeok= this->probe_detected ? 1 : 0;
 482
 483     // print results using the GRBL format
 484     gcode->stream->printf("[PRB:%1.3f,%1.3f,%1.3f:%d]\n", pos[X_AXIS], pos[Y_AXIS], pos[Z_AXIS], probeok);
 485     THEKERNEL->robot->set_last_probe_position(std::make_tuple(pos[X_AXIS], pos[Y_AXIS], pos[Z_AXIS], probeok));
 486
 487     if(!probeok) {
 488         if(gcode->subcode == 2) {
 489             // issue error if probe was not triggered and subcode == 2
 490             gcode->stream->printf("ALARM:Probe fail\n");
 491             THEKERNEL->call_event(ON_HALT, nullptr);
 492
 493         }else{
 494             // if the probe stopped the move we need to correct the last_milestone as it did not reach where it thought
 495             THEKERNEL->robot->reset_position_from_current_actuator_position();
 496         }
 497     }
 498 }
 499
 500 // Called periodically to change the speed to match acceleration
 501 void ZProbe::acceleration_tick(void)
 502 {
 503     if(!this->running) return; // nothing to do
 504     if(STEPPER[Z_AXIS]->is_moving()) accelerate(Z_AXIS);
 505
 506     if(is_delta) {
 507          // deltas needs to move all actuators
 508         for ( int c = X_AXIS; c <= Y_AXIS; c++ ) {
 509             if( !STEPPER[c]->is_moving() ) continue;
 510             accelerate(c);
 511         }
 512     }
 513
 514     return;
 515 }
 516
 517 void ZProbe::accelerate(int c)
 518 {   uint32_t current_rate = STEPPER[c]->get_steps_per_second();
 519     uint32_t target_rate = floorf(this->current_feedrate);
 520
 521     // Z may have a different acceleration to X and Y
 522     float acc= (c==Z_AXIS) ? THEKERNEL->planner->get_z_acceleration() : THEKERNEL->planner->get_acceleration();
 523     if( current_rate < target_rate ) {
 524         uint32_t rate_increase = floorf((acc / THEKERNEL->acceleration_ticks_per_second) * STEPS_PER_MM(c));
 525         current_rate = min( target_rate, current_rate + rate_increase );
 526     }
 527     if( current_rate > target_rate ) {
 528         current_rate = target_rate;
 529     }
 530
 531     // steps per second
 532     STEPPER[c]->set_speed(current_rate);
 533 }
 534
 535 // issue a coordinated move directly to robot, and return when done
 536 // Only move the coordinates that are passed in as not nan
 537 // NOTE must use G53 to force move in machine coordiantes and ignore any WCS offsetts
 538 void ZProbe::coordinated_move(float x, float y, float z, float feedrate, bool relative)
 539 {
 540     char buf[32];
 541     char cmd[64];
 542
 543     if(relative) strcpy(cmd, "G91 G0 ");
 544     else strcpy(cmd, "G53 G0 "); // G53 forces movement in machine coordinate system
 545
 546     if(!isnan(x)) {
 547         int n = snprintf(buf, sizeof(buf), " X%1.3f", x);
 548         strncat(cmd, buf, n);
 549     }
 550     if(!isnan(y)) {
 551         int n = snprintf(buf, sizeof(buf), " Y%1.3f", y);
 552         strncat(cmd, buf, n);
 553     }
 554     if(!isnan(z)) {
 555         int n = snprintf(buf, sizeof(buf), " Z%1.3f", z);
 556         strncat(cmd, buf, n);
 557     }
 558
 559     // use specified feedrate (mm/sec)
 560     int n = snprintf(buf, sizeof(buf), " F%1.1f", feedrate * 60); // feed rate is converted to mm/min
 561     strncat(cmd, buf, n);
 562     if(relative) strcat(cmd, " G90");
 563
 564     //THEKERNEL->streams->printf("DEBUG: move: %s\n", cmd);
 565
 566     // send as a command line as may have multiple G codes in it
 567     struct SerialMessage message;
 568     message.message = cmd;
 569     message.stream = &(StreamOutput::NullStream);
 570     THEKERNEL->call_event(ON_CONSOLE_LINE_RECEIVED, &message );
 571     THEKERNEL->conveyor->wait_for_empty_queue();
 572 }
 573
 574 // issue home command
 575 void ZProbe::home()
 576 {
 577     Gcode gc("G28", &(StreamOutput::NullStream));
 578     THEKERNEL->call_event(ON_GCODE_RECEIVED, &gc);
 579 }
 580
 581 float ZProbe::zsteps_to_mm(float steps)
 582 {
 583     return steps / Z_STEPS_PER_MM;
 584 }