src/modules/tools/extruder/Extruder.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 "Extruder.h"
   9
  10 #include "libs/Module.h"
  11 #include "libs/Kernel.h"
  12
  13 #include "modules/robot/Conveyor.h"
  14 #include "modules/robot/Block.h"
  15 #include "StepperMotor.h"
  16 #include "SlowTicker.h"
  17 #include "Stepper.h"
  18 #include "StepTicker.h"
  19 #include "Config.h"
  20 #include "StepperMotor.h"
  21 #include "Robot.h"
  22 #include "checksumm.h"
  23 #include "ConfigValue.h"
  24 #include "Gcode.h"
  25 #include "libs/StreamOutput.h"
  26 #include "PublicDataRequest.h"
  27
  28 #include <mri.h>
  29
  30 // OLD config names for backwards compatibility, NOTE new configs will not be added here
  31 #define extruder_module_enable_checksum      CHECKSUM("extruder_module_enable")
  32 #define extruder_steps_per_mm_checksum       CHECKSUM("extruder_steps_per_mm")
  33 #define extruder_filament_diameter_checksum  CHECKSUM("extruder_filament_diameter")
  34 #define extruder_acceleration_checksum       CHECKSUM("extruder_acceleration")
  35 #define extruder_step_pin_checksum           CHECKSUM("extruder_step_pin")
  36 #define extruder_dir_pin_checksum            CHECKSUM("extruder_dir_pin")
  37 #define extruder_en_pin_checksum             CHECKSUM("extruder_en_pin")
  38 #define extruder_max_speed_checksum          CHECKSUM("extruder_max_speed")
  39
  40 // NEW config names
  41 #define extruder_checksum                    CHECKSUM("extruder")
  42
  43 #define default_feed_rate_checksum           CHECKSUM("default_feed_rate")
  44 #define steps_per_mm_checksum                CHECKSUM("steps_per_mm")
  45 #define filament_diameter_checksum           CHECKSUM("filament_diameter")
  46 #define acceleration_checksum                CHECKSUM("acceleration")
  47 #define step_pin_checksum                    CHECKSUM("step_pin")
  48 #define dir_pin_checksum                     CHECKSUM("dir_pin")
  49 #define en_pin_checksum                      CHECKSUM("en_pin")
  50 #define max_speed_checksum                   CHECKSUM("max_speed")
  51 #define x_offset_checksum                    CHECKSUM("x_offset")
  52 #define y_offset_checksum                    CHECKSUM("y_offset")
  53 #define z_offset_checksum                    CHECKSUM("z_offset")
  54
  55 #define retract_length_checksum              CHECKSUM("retract_length")
  56 #define retract_feedrate_checksum            CHECKSUM("retract_feedrate")
  57 #define retract_recover_length_checksum      CHECKSUM("retract_recover_length")
  58 #define retract_recover_feedrate_checksum    CHECKSUM("retract_recover_feedrate")
  59 #define retract_zlift_length_checksum        CHECKSUM("retract_zlift_length")
  60 #define retract_zlift_feedrate_checksum      CHECKSUM("retract_zlift_feedrate")
  61
  62 #define X_AXIS      0
  63 #define Y_AXIS      1
  64 #define Z_AXIS      2
  65
  66 #define OFF 0
  67 #define SOLO 1
  68 #define FOLLOW 2
  69
  70 #define PI 3.14159265358979F
  71
  72 #define max(a,b) (((a) > (b)) ? (a) : (b))
  73
  74 /* The extruder module controls a filament extruder for 3D printing: http://en.wikipedia.org/wiki/Fused_deposition_modeling
  75 * It can work in two modes : either the head does not move, and the extruder moves the filament at a specified speed ( SOLO mode here )
  76 * or the head moves, and the extruder moves plastic at a speed proportional to the movement of the head ( FOLLOW mode here ).
  77 */
  78
  79 Extruder::Extruder( uint16_t config_identifier, bool single )
  80 {
  81     this->absolute_mode = true;
  82     this->enabled = false;
  83     this->paused = false;
  84     this->single_config = single;
  85     this->identifier = config_identifier;
  86     this->retracted = false;
  87     this->volumetric_multiplier = 1.0F;
  88     this->extruder_multiplier = 1.0F;
  89
  90     memset(this->offset, 0, sizeof(this->offset));
  91 }
  92
  93 void Extruder::on_halt(void *arg)
  94 {
  95     if(arg == nullptr) {
  96         // turn off motor
  97         this->en_pin.set(1);
  98         // disable if multi extruder
  99         if(!this->single_config)
 100             this->enabled= false;
 101         // stop moving if we are moving as the block queue flush won't do it for us
 102         if(this->stepper_motor->is_moving()) this->stepper_motor->move(0, 0);
 103     }
 104 }
 105
 106 void Extruder::on_module_loaded()
 107 {
 108
 109     // Settings
 110     this->on_config_reload(this);
 111
 112     // We work on the same Block as Stepper, so we need to know when it gets a new one and drops one
 113     this->register_for_event(ON_BLOCK_BEGIN);
 114     this->register_for_event(ON_BLOCK_END);
 115     this->register_for_event(ON_GCODE_RECEIVED);
 116     this->register_for_event(ON_GCODE_EXECUTE);
 117     this->register_for_event(ON_PLAY);
 118     this->register_for_event(ON_PAUSE);
 119     this->register_for_event(ON_HALT);
 120     this->register_for_event(ON_SPEED_CHANGE);
 121     this->register_for_event(ON_GET_PUBLIC_DATA);
 122
 123     // Start values
 124     this->target_position = 0;
 125     this->current_position = 0;
 126     this->unstepped_distance = 0;
 127     this->current_block = NULL;
 128     this->mode = OFF;
 129
 130     // Update speed every *acceleration_ticks_per_second*
 131     // TODO: Make this an independent setting
 132     THEKERNEL->slow_ticker->attach( THEKERNEL->stepper->get_acceleration_ticks_per_second() , this, &Extruder::acceleration_tick );
 133
 134     // Stepper motor object for the extruder
 135     this->stepper_motor  = THEKERNEL->step_ticker->add_stepper_motor( new StepperMotor(step_pin, dir_pin, en_pin) );
 136     this->stepper_motor->attach(this, &Extruder::stepper_motor_finished_move );
 137 }
 138
 139 // Get config
 140 void Extruder::on_config_reload(void *argument)
 141 {
 142     if( this->single_config ) {
 143         // If this module uses the old "single extruder" configuration style
 144
 145         this->steps_per_millimeter        = THEKERNEL->config->value(extruder_steps_per_mm_checksum      )->by_default(1)->as_number();
 146         this->filament_diameter           = THEKERNEL->config->value(extruder_filament_diameter_checksum )->by_default(0)->as_number();
 147         this->acceleration                = THEKERNEL->config->value(extruder_acceleration_checksum      )->by_default(1000)->as_number();
 148         this->max_speed                   = THEKERNEL->config->value(extruder_max_speed_checksum         )->by_default(1000)->as_number();
 149         this->feed_rate                   = THEKERNEL->config->value(default_feed_rate_checksum          )->by_default(1000)->as_number();
 150
 151         this->step_pin.from_string(         THEKERNEL->config->value(extruder_step_pin_checksum          )->by_default("nc" )->as_string())->as_output();
 152         this->dir_pin.from_string(          THEKERNEL->config->value(extruder_dir_pin_checksum           )->by_default("nc" )->as_string())->as_output();
 153         this->en_pin.from_string(           THEKERNEL->config->value(extruder_en_pin_checksum            )->by_default("nc" )->as_string())->as_output();
 154
 155         for(int i = 0; i < 3; i++) {
 156             this->offset[i] = 0;
 157         }
 158
 159         this->enabled = true;
 160
 161     } else {
 162         // If this module was created with the new multi extruder configuration style
 163
 164         this->steps_per_millimeter = THEKERNEL->config->value(extruder_checksum, this->identifier, steps_per_mm_checksum      )->by_default(1)->as_number();
 165         this->filament_diameter    = THEKERNEL->config->value(extruder_checksum, this->identifier, filament_diameter_checksum )->by_default(0)->as_number();
 166         this->acceleration         = THEKERNEL->config->value(extruder_checksum, this->identifier, acceleration_checksum      )->by_default(1000)->as_number();
 167         this->max_speed            = THEKERNEL->config->value(extruder_checksum, this->identifier, max_speed_checksum         )->by_default(1000)->as_number();
 168         this->feed_rate            = THEKERNEL->config->value(                                     default_feed_rate_checksum )->by_default(1000)->as_number();
 169
 170         this->step_pin.from_string( THEKERNEL->config->value(extruder_checksum, this->identifier, step_pin_checksum          )->by_default("nc" )->as_string())->as_output();
 171         this->dir_pin.from_string(  THEKERNEL->config->value(extruder_checksum, this->identifier, dir_pin_checksum           )->by_default("nc" )->as_string())->as_output();
 172         this->en_pin.from_string(   THEKERNEL->config->value(extruder_checksum, this->identifier, en_pin_checksum            )->by_default("nc" )->as_string())->as_output();
 173
 174         this->offset[X_AXIS] = THEKERNEL->config->value(extruder_checksum, this->identifier, x_offset_checksum          )->by_default(0)->as_number();
 175         this->offset[Y_AXIS] = THEKERNEL->config->value(extruder_checksum, this->identifier, y_offset_checksum          )->by_default(0)->as_number();
 176         this->offset[Z_AXIS] = THEKERNEL->config->value(extruder_checksum, this->identifier, z_offset_checksum          )->by_default(0)->as_number();
 177
 178     }
 179
 180     // these are only supported in the new syntax, no need to be backward compatible as they did not exist before the change
 181     this->retract_length           = THEKERNEL->config->value(extruder_checksum, this->identifier, retract_length_checksum)->by_default(3)->as_number();
 182     this->retract_feedrate         = THEKERNEL->config->value(extruder_checksum, this->identifier, retract_feedrate_checksum)->by_default(45)->as_number();
 183     this->retract_recover_length   = THEKERNEL->config->value(extruder_checksum, this->identifier, retract_recover_length_checksum)->by_default(0)->as_number();
 184     this->retract_recover_feedrate = THEKERNEL->config->value(extruder_checksum, this->identifier, retract_recover_feedrate_checksum)->by_default(8)->as_number();
 185     this->retract_zlift_length     = THEKERNEL->config->value(extruder_checksum, this->identifier, retract_zlift_length_checksum)->by_default(0)->as_number();
 186     this->retract_zlift_feedrate   = THEKERNEL->config->value(extruder_checksum, this->identifier, retract_zlift_feedrate_checksum)->by_default(100*60)->as_number(); // mm/min
 187
 188     if(filament_diameter > 0.01) {
 189         this->volumetric_multiplier = 1.0F / (powf(this->filament_diameter / 2, 2) * PI);
 190     }
 191 }
 192
 193 void Extruder::on_get_public_data(void* argument){
 194     PublicDataRequest* pdr = static_cast<PublicDataRequest*>(argument);
 195
 196     if(!pdr->starts_with(extruder_checksum)) return;
 197
 198     if(this->enabled) {
 199         // Note this is allowing both step/mm and filament diameter to be exposed via public data
 200         pdr->set_data_ptr(&this->steps_per_millimeter);
 201         pdr->set_taken();
 202     }
 203 }
 204
 205 // When the play/pause button is set to pause, or a module calls the ON_PAUSE event
 206 void Extruder::on_pause(void *argument)
 207 {
 208     this->paused = true;
 209     this->stepper_motor->pause();
 210 }
 211
 212 // When the play/pause button is set to play, or a module calls the ON_PLAY event
 213 void Extruder::on_play(void *argument)
 214 {
 215     this->paused = false;
 216     this->stepper_motor->unpause();
 217 }
 218
 219 void Extruder::on_gcode_received(void *argument)
 220 {
 221     Gcode *gcode = static_cast<Gcode *>(argument);
 222
 223     // M codes most execute immediately, most only execute if enabled
 224     if (gcode->has_m) {
 225         if (gcode->m == 114 && this->enabled) {
 226             char buf[16];
 227             int n = snprintf(buf, sizeof(buf), " E:%1.3f ", this->current_position);
 228             gcode->txt_after_ok.append(buf, n);
 229             gcode->mark_as_taken();
 230
 231         } else if (gcode->m == 92 && ( (this->enabled && !gcode->has_letter('P')) || (gcode->has_letter('P') && gcode->get_value('P') == this->identifier) ) ) {
 232             float spm = this->steps_per_millimeter;
 233             if (gcode->has_letter('E')) {
 234                 spm = gcode->get_value('E');
 235                 this->steps_per_millimeter = spm;
 236             }
 237
 238             gcode->stream->printf("E:%g ", spm);
 239             gcode->add_nl = true;
 240             gcode->mark_as_taken();
 241
 242         } else if (gcode->m == 200 && ( (this->enabled && !gcode->has_letter('P')) || (gcode->has_letter('P') && gcode->get_value('P') == this->identifier)) ) {
 243             if (gcode->has_letter('D')) {
 244                 THEKERNEL->conveyor->wait_for_empty_queue(); // only apply after the queue has emptied
 245                 this->filament_diameter = gcode->get_value('D');
 246                 if(filament_diameter > 0.01) {
 247                     this->volumetric_multiplier = 1.0F / (powf(this->filament_diameter / 2, 2) * PI);
 248                 }else{
 249                     this->volumetric_multiplier = 1.0F;
 250                 }
 251             }
 252             gcode->mark_as_taken();
 253
 254         } else if (gcode->m == 204 && gcode->has_letter('E') &&
 255                    ( (this->enabled && !gcode->has_letter('P')) || (gcode->has_letter('P') && gcode->get_value('P') == this->identifier)) ) {
 256             // extruder acceleration M204 Ennn mm/sec^2 (Pnnn sets the specific extruder for M500)
 257             this->acceleration= gcode->get_value('E');
 258             gcode->mark_as_taken();
 259
 260         } else if (gcode->m == 207 && ( (this->enabled && !gcode->has_letter('P')) || (gcode->has_letter('P') && gcode->get_value('P') == this->identifier)) ) {
 261             // M207 - set retract length S[positive mm] F[feedrate mm/min] Z[additional zlift/hop] Q[zlift feedrate mm/min]
 262             if(gcode->has_letter('S')) retract_length = gcode->get_value('S');
 263             if(gcode->has_letter('F')) retract_feedrate = gcode->get_value('F')/60.0F; // specified in mm/min converted to mm/sec
 264             if(gcode->has_letter('Z')) retract_zlift_length = gcode->get_value('Z');
 265             if(gcode->has_letter('Q')) retract_zlift_feedrate = gcode->get_value('Q');
 266             gcode->mark_as_taken();
 267
 268         } else if (gcode->m == 208 && ( (this->enabled && !gcode->has_letter('P')) || (gcode->has_letter('P') && gcode->get_value('P') == this->identifier)) ) {
 269             // M208 - set retract recover length S[positive mm surplus to the M207 S*] F[feedrate mm/min]
 270             if(gcode->has_letter('S')) retract_recover_length = gcode->get_value('S');
 271             if(gcode->has_letter('F')) retract_recover_feedrate = gcode->get_value('F')/60.0F; // specified in mm/min converted to mm/sec
 272             gcode->mark_as_taken();
 273
 274         } else if (gcode->m == 221 && this->enabled) { // M221 S100 change flow rate by percentage
 275             if(gcode->has_letter('S')) this->extruder_multiplier= gcode->get_value('S')/100.0F;
 276             gcode->mark_as_taken();
 277
 278         } else if (gcode->m == 500 || gcode->m == 503) { // M500 saves some volatile settings to config override file, M503 just prints the settings
 279             if( this->single_config ) {
 280                 gcode->stream->printf(";E Steps per mm:\nM92 E%1.4f\n", this->steps_per_millimeter);
 281                 gcode->stream->printf(";E Filament diameter:\nM200 D%1.4f\n", this->filament_diameter);
 282                 gcode->stream->printf(";E retract length, feedrate, zlift length, feedrate:\nM207 S%1.4f F%1.4f Z%1.4f Q%1.4f\n", this->retract_length, this->retract_feedrate*60.0F, this->retract_zlift_length, this->retract_zlift_feedrate);
 283                 gcode->stream->printf(";E retract recover length, feedrate:\nM208 S%1.4f F%1.4f\n", this->retract_recover_length, this->retract_recover_feedrate*60.0F);
 284                 gcode->stream->printf(";E acceleration mm/sec^2:\nM204 E%1.4f\n", this->acceleration);
 285
 286             } else {
 287                 gcode->stream->printf(";E Steps per mm:\nM92 E%1.4f P%d\n", this->steps_per_millimeter, this->identifier);
 288                 gcode->stream->printf(";E Filament diameter:\nM200 D%1.4f P%d\n", this->filament_diameter, this->identifier);
 289                 gcode->stream->printf(";E retract length, feedrate:\nM207 S%1.4f F%1.4f Z%1.4f Q%1.4f P%d\n", this->retract_length, this->retract_feedrate*60.0F, this->retract_zlift_length, this->retract_zlift_feedrate, this->identifier);
 290                 gcode->stream->printf(";E retract recover length, feedrate:\nM208 S%1.4f F%1.4f P%d\n", this->retract_recover_length, this->retract_recover_feedrate*60.0F, this->identifier);
 291                 gcode->stream->printf(";E acceleration mm/sec^2:\nM204 E%1.4f P%d\n", this->acceleration, this->identifier);
 292             }
 293             gcode->mark_as_taken();
 294         } else if( gcode->m == 17 || gcode->m == 18 || gcode->m == 82 || gcode->m == 83 || gcode->m == 84 ) {
 295             // Mcodes to pass along to on_gcode_execute
 296             THEKERNEL->conveyor->append_gcode(gcode);
 297             gcode->mark_as_taken();
 298         }
 299
 300     }else if(gcode->has_g) {
 301         // G codes, NOTE some are ignored if not enabled
 302         if( (gcode->g == 92 && gcode->has_letter('E')) || (gcode->g == 90 || gcode->g == 91) ) {
 303             // Gcodes to pass along to on_gcode_execute
 304             THEKERNEL->conveyor->append_gcode(gcode);
 305             gcode->mark_as_taken();
 306
 307         }else if( this->enabled && gcode->g < 4 && gcode->has_letter('E') && !gcode->has_letter('X') && !gcode->has_letter('Y') && !gcode->has_letter('Z') ) {
 308             // This is a solo move, we add an empty block to the queue to prevent subsequent gcodes being executed at the same time
 309             THEKERNEL->conveyor->append_gcode(gcode);
 310             THEKERNEL->conveyor->queue_head_block();
 311             gcode->mark_as_taken();
 312
 313         }else if( this->enabled && (gcode->g == 10 || gcode->g == 11) ) { // firmware retract command
 314             gcode->mark_as_taken();
 315             // check we are in the correct state of retract or unretract
 316             if(gcode->g == 10 && !retracted) {
 317                 this->retracted= true;
 318                 this->cancel_zlift_restore= false;
 319             } else if(gcode->g == 11 && retracted){
 320                 this->retracted= false;
 321             } else
 322                 return; // ignore duplicates
 323
 324             // now we do a special hack to add zlift if needed, this should go in Robot but if it did the zlift would be executed before retract which is bad
 325             // this way zlift will happen after retract, (or before for unretract) NOTE we call the robot->on_gcode_receive directly to avoid recursion
 326             if(retract_zlift_length > 0 && gcode->g == 11 && !this->cancel_zlift_restore) {
 327                 // reverse zlift happens before unretract
 328                 // NOTE we do not do this if cancel_zlift_restore is set to true, which happens if there is an absolute Z move inbetween G10 and G11
 329                 char buf[32];
 330                 int n= snprintf(buf, sizeof(buf), "G0 Z%1.4f F%1.4f", -retract_zlift_length, retract_zlift_feedrate);
 331                 string cmd(buf, n);
 332                 Gcode gc(cmd, &(StreamOutput::NullStream));
 333                 bool oldmode= THEKERNEL->robot->absolute_mode;
 334                 THEKERNEL->robot->absolute_mode= false; // needs to be relative mode
 335                 THEKERNEL->robot->on_gcode_received(&gc); // send to robot directly
 336                 THEKERNEL->robot->absolute_mode= oldmode; // restore mode
 337             }
 338
 339             // This is a solo move, we add an empty block to the queue to prevent subsequent gcodes being executed at the same time
 340             THEKERNEL->conveyor->append_gcode(gcode);
 341             THEKERNEL->conveyor->queue_head_block();
 342
 343             if(retract_zlift_length > 0 && gcode->g == 10) {
 344                 char buf[32];
 345                 int n= snprintf(buf, sizeof(buf), "G0 Z%1.4f F%1.4f", retract_zlift_length, retract_zlift_feedrate);
 346                 string cmd(buf, n);
 347                 Gcode gc(cmd, &(StreamOutput::NullStream));
 348                 bool oldmode= THEKERNEL->robot->absolute_mode;
 349                 THEKERNEL->robot->absolute_mode= false; // needs to be relative mode
 350                 THEKERNEL->robot->on_gcode_received(&gc); // send to robot directly
 351                 THEKERNEL->robot->absolute_mode= oldmode; // restore mode
 352             }
 353
 354         }else if( this->enabled && this->retracted && (gcode->g == 0 || gcode->g == 1) && gcode->has_letter('Z')) {
 355             // NOTE we cancel the zlift restore for the following G11 as we have moved to an absolute Z which we need to stay at
 356             this->cancel_zlift_restore= true;
 357         }
 358     }
 359 }
 360
 361 // Compute extrusion speed based on parameters and gcode distance of travel
 362 void Extruder::on_gcode_execute(void *argument)
 363 {
 364     Gcode *gcode = static_cast<Gcode *>(argument);
 365
 366     // The mode is OFF by default, and SOLO or FOLLOW only if we need to extrude
 367     this->mode = OFF;
 368
 369     // Absolute/relative mode, globably modal affect all extruders whether enabled or not
 370     if( gcode->has_m ) {
 371         switch(gcode->m) {
 372         case 17:
 373             this->en_pin.set(0);
 374             break;
 375         case 18:
 376             this->en_pin.set(1);
 377             break;
 378         case 82:
 379             this->absolute_mode = true;
 380             break;
 381         case 83:
 382             this->absolute_mode = false;
 383             break;
 384         case 84:
 385             this->en_pin.set(1);
 386             break;
 387         }
 388         return;
 389
 390     } else if( gcode->has_g && (gcode->g == 90 || gcode->g == 91) ) {
 391         this->absolute_mode = (gcode->g == 90);
 392         return;
 393     }
 394
 395
 396     if( gcode->has_g && this->enabled ) {
 397         // G92: Reset extruder position
 398         if( gcode->g == 92 ) {
 399             if( gcode->has_letter('E') ) {
 400                 this->current_position = gcode->get_value('E');
 401                 this->target_position  = this->current_position;
 402                 this->unstepped_distance = 0;
 403             } else if( gcode->get_num_args() == 0) {
 404                 this->current_position = 0.0;
 405                 this->target_position = this->current_position;
 406                 this->unstepped_distance = 0;
 407             }
 408
 409         } else if (gcode->g == 10) {
 410             // FW retract command
 411             feed_rate= retract_feedrate; // mm/sec
 412             this->mode = SOLO;
 413             this->travel_distance = -retract_length;
 414             this->target_position += this->travel_distance;
 415             this->en_pin.set(0);
 416
 417         } else if (gcode->g == 11) {
 418             // un retract command
 419             feed_rate= retract_recover_feedrate; // mm/sec
 420             this->mode = SOLO;
 421             this->travel_distance = (retract_length + retract_recover_length);
 422             this->target_position += this->travel_distance;
 423             this->en_pin.set(0);
 424
 425         } else if (gcode->g == 0 || gcode->g == 1) {
 426             // Extrusion length from 'G' Gcode
 427             if( gcode->has_letter('E' )) {
 428                 // Get relative extrusion distance depending on mode ( in absolute mode we must substract target_position )
 429                 float extrusion_distance = gcode->get_value('E');
 430                 float relative_extrusion_distance = extrusion_distance;
 431                 if (this->absolute_mode) {
 432                     relative_extrusion_distance -= this->target_position;
 433                     this->target_position = extrusion_distance;
 434                 } else {
 435                     this->target_position += relative_extrusion_distance;
 436                 }
 437
 438                 // If the robot is moving, we follow it's movement, otherwise, we move alone
 439                 if( fabs(gcode->millimeters_of_travel) < 0.0001F ) { // With floating numbers, we can have 0 != 0 ... beeeh. For more info see : http://upload.wikimedia.org/wikipedia/commons/0/0a/Cain_Henri_Vidal_Tuileries.jpg
 440                     this->mode = SOLO;
 441                     this->travel_distance = relative_extrusion_distance;
 442                 } else {
 443                     // We move proportionally to the robot's movement
 444                     this->mode = FOLLOW;
 445                     this->travel_ratio = (relative_extrusion_distance * this->volumetric_multiplier * this->extruder_multiplier) / gcode->millimeters_of_travel; // adjust for volumetric extrusion and extruder multiplier
 446                     // TODO: check resulting flowrate, limit robot speed if it exceeds max_speed
 447                 }
 448
 449                 this->en_pin.set(0);
 450             }
 451
 452             if (gcode->has_letter('F')) {
 453                 feed_rate = gcode->get_value('F') / THEKERNEL->robot->get_seconds_per_minute();
 454                 if (feed_rate > max_speed)
 455                     feed_rate = max_speed;
 456             }
 457         }
 458     }
 459
 460 }
 461
 462 // When a new block begins, either follow the robot, or step by ourselves ( or stay back and do nothing )
 463 void Extruder::on_block_begin(void *argument)
 464 {
 465     if(!this->enabled) return;
 466     Block *block = static_cast<Block *>(argument);
 467
 468
 469     if( this->mode == SOLO ) {
 470         // In solo mode we take the block so we can move even if the stepper has nothing to do
 471
 472         this->current_position += this->travel_distance ;
 473
 474         int steps_to_step = abs(int(floor(this->steps_per_millimeter * (this->travel_distance + this->unstepped_distance) )));
 475
 476         if ( this->travel_distance > 0 ) {
 477             this->unstepped_distance += this->travel_distance - (steps_to_step / this->steps_per_millimeter); //catch any overflow
 478         }   else {
 479             this->unstepped_distance += this->travel_distance + (steps_to_step / this->steps_per_millimeter); //catch any overflow
 480         }
 481
 482         if( steps_to_step != 0 ) {
 483
 484             // We take the block, we have to release it or everything gets stuck
 485             block->take();
 486             this->current_block = block;
 487
 488             this->stepper_motor->move( ( this->travel_distance > 0 ), steps_to_step, 0);
 489
 490         } else {
 491             this->current_block = NULL;
 492         }
 493
 494     } else if( this->mode == FOLLOW ) {
 495         // In non-solo mode, we just follow the stepper module
 496         this->travel_distance = block->millimeters * this->travel_ratio;
 497
 498         this->current_position += this->travel_distance;
 499
 500         int steps_to_step = abs(int(floor(this->steps_per_millimeter * (this->travel_distance + this->unstepped_distance) )));
 501
 502         if ( this->travel_distance > 0 ) {
 503             this->unstepped_distance += this->travel_distance - (steps_to_step / this->steps_per_millimeter); //catch any overflow
 504         }   else {
 505             this->unstepped_distance += this->travel_distance + (steps_to_step / this->steps_per_millimeter); //catch any overflow
 506         }
 507
 508         if( steps_to_step != 0 ) {
 509             block->take();
 510             this->current_block = block;
 511
 512             this->stepper_motor->move( ( this->travel_distance > 0 ), steps_to_step);
 513             on_speed_change(0); // set initial speed
 514         } else {
 515             this->current_block = NULL;
 516         }
 517
 518     } else if( this->mode == OFF ) {
 519         // No movement means we must reset our speed
 520         this->current_block = NULL;
 521         //this->stepper_motor->set_speed(0);
 522
 523     }
 524
 525 }
 526
 527 // When a block ends, pause the stepping interrupt
 528 void Extruder::on_block_end(void *argument)
 529 {
 530     if(!this->enabled) return;
 531     this->current_block = NULL;
 532 }
 533
 534 // Called periodically to change the speed to match acceleration or to match the speed of the robot
 535 // Only used in SOLO mode
 536 uint32_t Extruder::acceleration_tick(uint32_t dummy)
 537 {
 538     if(!this->enabled) return 0;
 539
 540     // Avoid trying to work when we really shouldn't ( between blocks or re-entry )
 541     if( this->current_block == NULL ||  this->paused || this->mode != SOLO ) {
 542         return 0;
 543     }
 544
 545     if(!this->stepper_motor->is_moving()) return 0;
 546
 547     uint32_t current_rate = this->stepper_motor->get_steps_per_second();
 548     uint32_t target_rate = int(floor(this->feed_rate * this->steps_per_millimeter));
 549
 550     if( current_rate < target_rate ) {
 551         uint32_t rate_increase = int(floor((this->acceleration / THEKERNEL->stepper->get_acceleration_ticks_per_second()) * this->steps_per_millimeter));
 552         current_rate = min( target_rate, current_rate + rate_increase );
 553     }
 554     if( current_rate > target_rate ) {
 555         current_rate = target_rate;
 556     }
 557
 558     // steps per second
 559     this->stepper_motor->set_speed(current_rate);
 560
 561     return 0;
 562 }
 563
 564 // Speed has been updated for the robot's stepper, we must update accordingly
 565 void Extruder::on_speed_change( void *argument )
 566 {
 567     if(!this->enabled) return;
 568
 569     // Avoid trying to work when we really shouldn't ( between blocks or re-entry )
 570     if( this->current_block == NULL ||  this->paused || this->mode != FOLLOW || !this->stepper_motor->is_moving()) {
 571         return;
 572     }
 573
 574     // if we are flushing the queue we need to stop the motor when it has decelerated to zero
 575     // this is what steppermotor does
 576     if(THEKERNEL->conveyor->is_flushing() && THEKERNEL->stepper->get_trapezoid_adjusted_rate() == this->current_block->rate_delta * 0.5F) {
 577         this->stepper_motor->move(0, 0);
 578         this->current_block->release();
 579         this->current_block = NULL;
 580         return;
 581     }
 582
 583     /*
 584     * nominal block duration = current block's steps / ( current block's nominal rate )
 585     * nominal extruder rate = extruder steps / nominal block duration
 586     * actual extruder rate = nominal extruder rate * ( ( stepper's steps per second ) / ( current block's nominal rate ) )
 587     * or actual extruder rate = ( ( extruder steps * ( current block's nominal_rate ) ) / current block's steps ) * ( ( stepper's steps per second ) / ( current block's nominal rate ) )
 588     * or simplified : extruder steps * ( stepper's steps per second ) ) / current block's steps
 589     * or even : ( stepper steps per second ) * ( extruder steps / current block's steps )
 590     */
 591
 592     this->stepper_motor->set_speed(THEKERNEL->stepper->get_trapezoid_adjusted_rate() * (float)this->stepper_motor->get_steps_to_move() / (float)this->current_block->steps_event_count);
 593
 594 }
 595
 596 // When the stepper has finished it's move
 597 uint32_t Extruder::stepper_motor_finished_move(uint32_t dummy)
 598 {
 599     if(!this->enabled) return 0;
 600
 601     //printf("extruder releasing\r\n");
 602
 603     if (this->current_block) { // this should always be true, but sometimes it isn't. TODO: find out why
 604         Block *block = this->current_block;
 605         this->current_block = NULL;
 606         block->release();
 607     }
 608     return 0;
 609
 610 }