Extruder.cpp

00001 /*
00002     This file is part of Smoothie (http://smoothieware.org/). The motion control part is heavily based on Grbl (https://github.com/simen/grbl).
00003     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.
00004     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.
00005     You should have received a copy of the GNU General Public License along with Smoothie. If not, see <http://www.gnu.org/licenses/>.
00006 */
00007 
00008 #include "Extruder.h"
00009 
00010 #include "libs/Module.h"
00011 #include "libs/Kernel.h"
00012 
00013 #include "modules/robot/Conveyor.h"
00014 #include "modules/robot/Block.h"
00015 #include "StepperMotor.h"
00016 
00017 #include <mri.h>
00018 
00019 #define extruder_module_enable_checksum      CHECKSUM("extruder_module_enable")
00020 #define extruder_steps_per_mm_checksum       CHECKSUM("extruder_steps_per_mm")
00021 #define extruder_acceleration_checksum       CHECKSUM("extruder_acceleration")
00022 #define extruder_step_pin_checksum           CHECKSUM("extruder_step_pin")
00023 #define extruder_dir_pin_checksum            CHECKSUM("extruder_dir_pin")
00024 #define extruder_en_pin_checksum             CHECKSUM("extruder_en_pin")
00025 #define extruder_max_speed_checksum          CHECKSUM("extruder_max_speed")
00026 
00027 #define extruder_checksum                    CHECKSUM("extruder")
00028 
00029 #define default_feed_rate_checksum           CHECKSUM("default_feed_rate")
00030 #define steps_per_mm_checksum                CHECKSUM("steps_per_mm")
00031 #define acceleration_checksum                CHECKSUM("acceleration")
00032 #define step_pin_checksum                    CHECKSUM("step_pin")
00033 #define dir_pin_checksum                     CHECKSUM("dir_pin")
00034 #define en_pin_checksum                      CHECKSUM("en_pin")
00035 #define max_speed_checksum                   CHECKSUM("max_speed")
00036 
00037 #define max(a,b) (((a) > (b)) ? (a) : (b))
00038 
00039 /* The extruder module controls a filament extruder for 3D printing: http://en.wikipedia.org/wiki/Fused_deposition_modeling
00040 * 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 )
00041 * or the head moves, and the extruder moves plastic at a speed proportional to the movement of the head ( FOLLOW mode here ).
00042 */
00043 
00044 Extruder::Extruder( uint16_t config_identifier ) {
00045     this->absolute_mode = true;
00046     this->paused        = false;
00047     this->single_config = false;
00048     this->identifier    = config_identifier;
00049 }
00050 
00051 void Extruder::on_module_loaded() {
00052 
00053     // Settings
00054     this->on_config_reload(this);
00055 
00056     // We work on the same Block as Stepper, so we need to know when it gets a new one and drops one
00057     register_for_event(ON_CONFIG_RELOAD);
00058     this->register_for_event(ON_BLOCK_BEGIN);
00059     this->register_for_event(ON_BLOCK_END);
00060     this->register_for_event(ON_GCODE_RECEIVED);
00061     this->register_for_event(ON_GCODE_EXECUTE);
00062     this->register_for_event(ON_PLAY);
00063     this->register_for_event(ON_PAUSE);
00064     this->register_for_event(ON_SPEED_CHANGE);
00065 
00066     // Start values
00067     this->target_position = 0;
00068     this->current_position = 0;
00069     this->unstepped_distance = 0;
00070     this->current_block = NULL;
00071     this->mode = OFF;
00072 
00073     // Update speed every *acceleration_ticks_per_second*
00074     // TODO: Make this an independent setting
00075     THEKERNEL->slow_ticker->attach( THEKERNEL->stepper->acceleration_ticks_per_second , this, &Extruder::acceleration_tick );
00076 
00077     // Stepper motor object for the extruder
00078     this->stepper_motor  = THEKERNEL->step_ticker->add_stepper_motor( new StepperMotor(step_pin, dir_pin, en_pin) );
00079     this->stepper_motor->attach(this, &Extruder::stepper_motor_finished_move );
00080 
00081 }
00082 
00083 // Get config
00084 void Extruder::on_config_reload(void* argument){
00085 
00086     // If this module uses the old "single extruder" configuration style
00087     if( this->single_config ){
00088 
00089         this->steps_per_millimeter        = THEKERNEL->config->value(extruder_steps_per_mm_checksum      )->by_default(1)->as_number();
00090         this->acceleration                = THEKERNEL->config->value(extruder_acceleration_checksum      )->by_default(1000)->as_number();
00091         this->max_speed                   = THEKERNEL->config->value(extruder_max_speed_checksum         )->by_default(1000)->as_number();
00092         this->feed_rate                   = THEKERNEL->config->value(default_feed_rate_checksum          )->by_default(1000)->as_number();
00093 
00094         this->step_pin.from_string(         THEKERNEL->config->value(extruder_step_pin_checksum          )->by_default("nc" )->as_string())->as_output();
00095         this->dir_pin.from_string(          THEKERNEL->config->value(extruder_dir_pin_checksum           )->by_default("nc" )->as_string())->as_output();
00096         this->en_pin.from_string(           THEKERNEL->config->value(extruder_en_pin_checksum            )->by_default("nc" )->as_string())->as_output();
00097 
00098     }else{
00099     // If this module was created with the new multi extruder configuration style
00100 
00101         this->steps_per_millimeter        = THEKERNEL->config->value(extruder_checksum, this->identifier, steps_per_mm_checksum      )->by_default(1)->as_number();
00102         this->acceleration                = THEKERNEL->config->value(extruder_checksum, this->identifier, acceleration_checksum      )->by_default(1000)->as_number();
00103         this->max_speed                   = THEKERNEL->config->value(extruder_checksum, this->identifier, max_speed_checksum         )->by_default(1000)->as_number();
00104         this->feed_rate                   = THEKERNEL->config->value(                                     default_feed_rate_checksum )->by_default(1000)->as_number();
00105 
00106         this->step_pin.from_string(         THEKERNEL->config->value(extruder_checksum, this->identifier, step_pin_checksum          )->by_default("nc" )->as_string())->as_output();
00107         this->dir_pin.from_string(          THEKERNEL->config->value(extruder_checksum, this->identifier, dir_pin_checksum           )->by_default("nc" )->as_string())->as_output();
00108         this->en_pin.from_string(           THEKERNEL->config->value(extruder_checksum, this->identifier, en_pin_checksum            )->by_default("nc" )->as_string())->as_output();
00109 
00110     }
00111 
00112 }
00113 
00114 
00115 // When the play/pause button is set to pause, or a module calls the ON_PAUSE event
00116 void Extruder::on_pause(void* argument){
00117     this->paused = true;
00118     this->stepper_motor->pause();
00119 }
00120 
00121 // When the play/pause button is set to play, or a module calls the ON_PLAY event
00122 void Extruder::on_play(void* argument){
00123     this->paused = false;
00124     this->stepper_motor->unpause();
00125 }
00126 
00127 
00128 void Extruder::on_gcode_received(void *argument){
00129     Gcode *gcode = static_cast<Gcode*>(argument);
00130 
00131     // Gcodes to execute immediately
00132     if (gcode->has_m){
00133         if (gcode->m == 114){
00134             gcode->stream->printf("E:%4.1f ", this->current_position);
00135             gcode->add_nl = true;
00136             gcode->mark_as_taken();
00137 
00138         }else if (gcode->m == 92 ){
00139             float spm = this->steps_per_millimeter;
00140             if (gcode->has_letter('E'))
00141                 spm = gcode->get_value('E');
00142             gcode->stream->printf("E:%g ", spm);
00143             gcode->add_nl = true;
00144             gcode->mark_as_taken();
00145 
00146         }else if (gcode->m == 500 || gcode->m == 503){// M500 saves some volatile settings to config override file, M503 just prints the settings
00147             gcode->stream->printf(";E Steps per mm:\nM92 E%1.4f\n", this->steps_per_millimeter);
00148             gcode->mark_as_taken();
00149             return;
00150         }
00151     }
00152 
00153     // Gcodes to pass along to on_gcode_execute
00154     if( ( gcode->has_m && (gcode->m == 17 || gcode->m == 18 || gcode->m == 82 || gcode->m == 83 || gcode->m == 84 || gcode->m == 92 ) ) || ( gcode->has_g && gcode->g == 92 && gcode->has_letter('E') ) || ( gcode->has_g && ( gcode->g == 90 || gcode->g == 91 ) ) ){
00155         THEKERNEL->conveyor->append_gcode(gcode);
00156     }
00157 
00158     // Add to the queue for on_gcode_execute to process
00159     if( gcode->has_g && gcode->g < 4 && gcode->has_letter('E') ){
00160         if( !gcode->has_letter('X') && !gcode->has_letter('Y') && !gcode->has_letter('Z') ){
00161             THEKERNEL->conveyor->append_gcode(gcode);
00162             // This is a solo move, we add an empty block to the queue to prevent subsequent gcodes being executed at the same time
00163             THEKERNEL->conveyor->queue_head_block();
00164         }
00165     }else{
00166         // This is for follow move
00167 
00168     }
00169 }
00170 
00171 // Compute extrusion speed based on parameters and gcode distance of travel
00172 void Extruder::on_gcode_execute(void* argument){
00173     Gcode* gcode = static_cast<Gcode*>(argument);
00174 
00175     // Absolute/relative mode
00176     if( gcode->has_m ){
00177         if( gcode->m == 17 ){ this->en_pin.set(0); }
00178         if( gcode->m == 18 ){ this->en_pin.set(1); }
00179         if( gcode->m == 82 ){ this->absolute_mode = true; }
00180         if( gcode->m == 83 ){ this->absolute_mode = false; }
00181         if( gcode->m == 84 ){ this->en_pin.set(1); }
00182         if (gcode->m == 92 ){
00183             if (gcode->has_letter('E')){
00184                 this->steps_per_millimeter = gcode->get_value('E');
00185             }
00186         }
00187     }
00188 
00189     // The mode is OFF by default, and SOLO or FOLLOW only if we need to extrude
00190     this->mode = OFF;
00191 
00192     if( gcode->has_g ){
00193         // G92: Reset extruder position
00194         if( gcode->g == 92 ){
00195             gcode->mark_as_taken();
00196             if( gcode->has_letter('E') ){
00197                 this->current_position = gcode->get_value('E');
00198                 this->target_position  = this->current_position;
00199                 this->unstepped_distance = 0;
00200             }else if( gcode->get_num_args() == 0){
00201                 this->current_position = 0.0;
00202                 this->target_position = this->current_position;
00203                 this->unstepped_distance = 0;
00204             }
00205         }else if ((gcode->g == 0) || (gcode->g == 1)){
00206             // Extrusion length from 'G' Gcode
00207             if( gcode->has_letter('E' )){
00208                 // Get relative extrusion distance depending on mode ( in absolute mode we must substract target_position )
00209                 float extrusion_distance = gcode->get_value('E');
00210                 float relative_extrusion_distance = extrusion_distance;
00211                 if (this->absolute_mode)
00212                 {
00213                     relative_extrusion_distance -= this->target_position;
00214                     this->target_position = extrusion_distance;
00215                 }
00216                 else
00217                 {
00218                     this->target_position += relative_extrusion_distance;
00219                 }
00220 
00221                 // If the robot is moving, we follow it's movement, otherwise, we move alone
00222                 if( fabs(gcode->millimeters_of_travel) < 0.0001 ){  // 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
00223                     this->mode = SOLO;
00224                     this->travel_distance = relative_extrusion_distance;
00225                 }else{
00226                     // We move proportionally to the robot's movement
00227                     this->mode = FOLLOW;
00228                     this->travel_ratio = relative_extrusion_distance / gcode->millimeters_of_travel;
00229                     // TODO: check resulting flowrate, limit robot speed if it exceeds max_speed
00230                 }
00231 
00232                 this->en_pin.set(0);
00233             }
00234             if (gcode->has_letter('F'))
00235             {
00236                 feed_rate = gcode->get_value('F') / THEKERNEL->robot->seconds_per_minute;
00237                 if (feed_rate > max_speed)
00238                     feed_rate = max_speed;
00239             }
00240         }else if( gcode->g == 90 ){ this->absolute_mode = true;
00241         }else if( gcode->g == 91 ){ this->absolute_mode = false;
00242         }
00243     }
00244 }
00245 
00246 // When a new block begins, either follow the robot, or step by ourselves ( or stay back and do nothing )
00247 void Extruder::on_block_begin(void* argument){
00248     Block* block = static_cast<Block*>(argument);
00249 
00250 
00251     if( this->mode == SOLO ){
00252         // In solo mode we take the block so we can move even if the stepper has nothing to do
00253 
00254         this->current_position += this->travel_distance ;
00255 
00256         int steps_to_step = abs(int(floor(this->steps_per_millimeter * (this->travel_distance +this->unstepped_distance) )));
00257 
00258         if ( this->travel_distance > 0 ){
00259             this->unstepped_distance += this->travel_distance -(steps_to_step/this->steps_per_millimeter); //catch any overflow
00260         }   else {
00261             this->unstepped_distance += this->travel_distance +(steps_to_step/this->steps_per_millimeter); //catch any overflow
00262         }
00263 
00264         if( steps_to_step != 0 ){
00265 
00266             // We take the block, we have to release it or everything gets stuck
00267             block->take();
00268             this->current_block = block;
00269 
00270             this->stepper_motor->steps_per_second = 0;
00271             this->stepper_motor->move( ( this->travel_distance > 0 ), steps_to_step);
00272 
00273         }else{
00274             this->current_block = NULL;
00275         }
00276 
00277     }else if( this->mode == FOLLOW ){
00278         // In non-solo mode, we just follow the stepper module
00279         this->travel_distance = block->millimeters * this->travel_ratio;
00280 
00281         this->current_position += this->travel_distance;
00282 
00283         int steps_to_step = abs(int(floor(this->steps_per_millimeter * (this->travel_distance + this->unstepped_distance) )));
00284 
00285         if ( this->travel_distance > 0 ){
00286             this->unstepped_distance += this->travel_distance -(steps_to_step/this->steps_per_millimeter); //catch any overflow
00287         }   else {
00288             this->unstepped_distance += this->travel_distance +(steps_to_step/this->steps_per_millimeter); //catch any overflow
00289         }
00290 
00291         if( steps_to_step != 0 ){
00292             block->take();
00293             this->current_block = block;
00294 
00295             this->stepper_motor->move( ( this->travel_distance > 0 ), steps_to_step );
00296             this->on_speed_change(0); // initialise speed in case we get called first
00297         }else{
00298             this->current_block = NULL;
00299         }
00300 
00301     }else if( this->mode == OFF ){
00302         // No movement means we must reset our speed
00303         this->current_block = NULL;
00304         //this->stepper_motor->set_speed(0);
00305 
00306     }
00307 
00308 }
00309 
00310 // When a block ends, pause the stepping interrupt
00311 void Extruder::on_block_end(void* argument){
00312     this->current_block = NULL;
00313 }
00314 
00315 // Called periodically to change the speed to match acceleration or to match the speed of the robot
00316 uint32_t Extruder::acceleration_tick(uint32_t dummy){
00317 
00318     // Avoid trying to work when we really shouldn't ( between blocks or re-entry )
00319     if( this->current_block == NULL ||  this->paused || this->mode != SOLO ){ return 0; }
00320 
00321     uint32_t current_rate = this->stepper_motor->steps_per_second;
00322     uint32_t target_rate = int(floor(this->feed_rate * this->steps_per_millimeter));
00323 
00324     if( current_rate < target_rate ){
00325         uint32_t rate_increase = int(floor((this->acceleration/THEKERNEL->stepper->acceleration_ticks_per_second)*this->steps_per_millimeter));
00326         current_rate = min( target_rate, current_rate + rate_increase );
00327     }
00328     if( current_rate > target_rate ){ current_rate = target_rate; }
00329 
00330     // steps per second
00331     this->stepper_motor->set_speed(max(current_rate, THEKERNEL->stepper->minimum_steps_per_second));
00332 
00333     return 0;
00334 }
00335 
00336 // Speed has been updated for the robot's stepper, we must update accordingly
00337 void Extruder::on_speed_change( void* argument ){
00338 
00339     // Avoid trying to work when we really shouldn't ( between blocks or re-entry )
00340     if( this->current_block == NULL ||  this->paused || this->mode != FOLLOW || this->stepper_motor->moving != true ){ return; }
00341 
00342     /*
00343     * nominal block duration = current block's steps / ( current block's nominal rate )
00344     * nominal extruder rate = extruder steps / nominal block duration
00345     * actual extruder rate = nominal extruder rate * ( ( stepper's steps per second ) / ( current block's nominal rate ) )
00346     * 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 ) )
00347     * or simplified : extruder steps * ( stepper's steps per second ) ) / current block's steps
00348     * or even : ( stepper steps per second ) * ( extruder steps / current block's steps )
00349     */
00350 
00351     this->stepper_motor->set_speed( max( ( THEKERNEL->stepper->trapezoid_adjusted_rate) * ( (float)this->stepper_motor->steps_to_move / (float)this->current_block->steps_event_count ), THEKERNEL->stepper->minimum_steps_per_second ) );
00352 
00353 }
00354 
00355 
00356 
00357 // When the stepper has finished it's move
00358 uint32_t Extruder::stepper_motor_finished_move(uint32_t dummy){
00359 
00360     //printf("extruder releasing\r\n");
00361 
00362     if (this->current_block){ // this should always be true, but sometimes it isn't. TODO: find out why
00363         Block* block = this->current_block;
00364         this->current_block = NULL;
00365         block->release();
00366     }
00367     return 0;
00368 
00369 }
00370