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MarlinFirmware/Marlin/planner.cpp

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/**
* Marlin 3D Printer Firmware
* Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
*
* Based on Sprinter and grbl.
* Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
*
* This program 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.
*
* This program 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
/**
* planner.cpp
*
* Buffer movement commands and manage the acceleration profile plan
*
* Derived from Grbl
* Copyright (c) 2009-2011 Simen Svale Skogsrud
*
* The ring buffer implementation gleaned from the wiring_serial library by David A. Mellis.
*
*
* Reasoning behind the mathematics in this module (in the key of 'Mathematica'):
*
* s == speed, a == acceleration, t == time, d == distance
*
* Basic definitions:
* Speed[s_, a_, t_] := s + (a*t)
* Travel[s_, a_, t_] := Integrate[Speed[s, a, t], t]
*
* Distance to reach a specific speed with a constant acceleration:
* Solve[{Speed[s, a, t] == m, Travel[s, a, t] == d}, d, t]
* d -> (m^2 - s^2)/(2 a) --> estimate_acceleration_distance()
*
* Speed after a given distance of travel with constant acceleration:
* Solve[{Speed[s, a, t] == m, Travel[s, a, t] == d}, m, t]
* m -> Sqrt[2 a d + s^2]
*
* DestinationSpeed[s_, a_, d_] := Sqrt[2 a d + s^2]
*
* When to start braking (di) to reach a specified destination speed (s2) after accelerating
* from initial speed s1 without ever stopping at a plateau:
* Solve[{DestinationSpeed[s1, a, di] == DestinationSpeed[s2, a, d - di]}, di]
* di -> (2 a d - s1^2 + s2^2)/(4 a) --> intersection_distance()
*
* IntersectionDistance[s1_, s2_, a_, d_] := (2 a d - s1^2 + s2^2)/(4 a)
*
*/
#include "Marlin.h"
#include "planner.h"
#include "stepper.h"
#include "temperature.h"
#include "ultralcd.h"
#include "language.h"
#if ENABLED(MESH_BED_LEVELING)
#include "mesh_bed_leveling.h"
#endif
Planner planner;
// public:
/**
* A ring buffer of moves described in steps
*/
block_t Planner::block_buffer[BLOCK_BUFFER_SIZE];
volatile uint8_t Planner::block_buffer_head = 0; // Index of the next block to be pushed
volatile uint8_t Planner::block_buffer_tail = 0;
float Planner::max_feedrate[NUM_AXIS]; // Max speeds in mm per minute
float Planner::axis_steps_per_mm[NUM_AXIS];
unsigned long Planner::max_acceleration_steps_per_s2[NUM_AXIS];
unsigned long Planner::max_acceleration_mm_per_s2[NUM_AXIS]; // Use M201 to override by software
millis_t Planner::min_segment_time;
float Planner::min_feedrate;
float Planner::acceleration; // Normal acceleration mm/s^2 DEFAULT ACCELERATION for all printing moves. M204 SXXXX
float Planner::retract_acceleration; // Retract acceleration mm/s^2 filament pull-back and push-forward while standing still in the other axes M204 TXXXX
float Planner::travel_acceleration; // Travel acceleration mm/s^2 DEFAULT ACCELERATION for all NON printing moves. M204 MXXXX
float Planner::max_xy_jerk; // The largest speed change requiring no acceleration
float Planner::max_z_jerk;
float Planner::max_e_jerk;
float Planner::min_travel_feedrate;
#if ENABLED(AUTO_BED_LEVELING_FEATURE)
matrix_3x3 Planner::bed_level_matrix; // Transform to compensate for bed level
#endif
#if ENABLED(AUTOTEMP)
float Planner::autotemp_max = 250;
float Planner::autotemp_min = 210;
float Planner::autotemp_factor = 0.1;
bool Planner::autotemp_enabled = false;
#endif
// private:
long Planner::position[NUM_AXIS] = { 0 };
float Planner::previous_speed[NUM_AXIS];
float Planner::previous_nominal_speed;
#if ENABLED(DISABLE_INACTIVE_EXTRUDER)
uint8_t Planner::g_uc_extruder_last_move[EXTRUDERS] = { 0 };
#endif // DISABLE_INACTIVE_EXTRUDER
#ifdef XY_FREQUENCY_LIMIT
// Old direction bits. Used for speed calculations
unsigned char Planner::old_direction_bits = 0;
// Segment times (in µs). Used for speed calculations
long Planner::axis_segment_time[2][3] = { {MAX_FREQ_TIME + 1, 0, 0}, {MAX_FREQ_TIME + 1, 0, 0} };
#endif
/**
* Class and Instance Methods
*/
Planner::Planner() {
#if ENABLED(AUTO_BED_LEVELING_FEATURE)
bed_level_matrix.set_to_identity();
#endif
init();
}
void Planner::init() {
block_buffer_head = block_buffer_tail = 0;
memset(position, 0, sizeof(position)); // clear position
for (int i = 0; i < NUM_AXIS; i++) previous_speed[i] = 0.0;
previous_nominal_speed = 0.0;
}
/**
* Calculate trapezoid parameters, multiplying the entry- and exit-speeds
* by the provided factors.
*/
void Planner::calculate_trapezoid_for_block(block_t* block, float entry_factor, float exit_factor) {
unsigned long initial_rate = ceil(block->nominal_rate * entry_factor),
final_rate = ceil(block->nominal_rate * exit_factor); // (steps per second)
// Limit minimal step rate (Otherwise the timer will overflow.)
NOLESS(initial_rate, 120);
NOLESS(final_rate, 120);
long accel = block->acceleration_steps_per_s2;
int32_t accelerate_steps = ceil(estimate_acceleration_distance(initial_rate, block->nominal_rate, accel));
int32_t decelerate_steps = floor(estimate_acceleration_distance(block->nominal_rate, final_rate, -accel));
// Calculate the size of Plateau of Nominal Rate.
int32_t plateau_steps = block->step_event_count - accelerate_steps - decelerate_steps;
// Is the Plateau of Nominal Rate smaller than nothing? That means no cruising, and we will
// have to use intersection_distance() to calculate when to abort accel and start braking
// in order to reach the final_rate exactly at the end of this block.
if (plateau_steps < 0) {
accelerate_steps = ceil(intersection_distance(initial_rate, final_rate, accel, block->step_event_count));
accelerate_steps = max(accelerate_steps, 0); // Check limits due to numerical round-off
accelerate_steps = min((uint32_t)accelerate_steps, block->step_event_count);//(We can cast here to unsigned, because the above line ensures that we are above zero)
plateau_steps = 0;
}
#if ENABLED(ADVANCE)
volatile long initial_advance = block->advance * entry_factor * entry_factor;
volatile long final_advance = block->advance * exit_factor * exit_factor;
#endif // ADVANCE
// block->accelerate_until = accelerate_steps;
// block->decelerate_after = accelerate_steps+plateau_steps;
CRITICAL_SECTION_START; // Fill variables used by the stepper in a critical section
if (!block->busy) { // Don't update variables if block is busy.
block->accelerate_until = accelerate_steps;
block->decelerate_after = accelerate_steps + plateau_steps;
block->initial_rate = initial_rate;
block->final_rate = final_rate;
#if ENABLED(ADVANCE)
block->initial_advance = initial_advance;
block->final_advance = final_advance;
#endif
}
CRITICAL_SECTION_END;
}
// "Junction jerk" in this context is the immediate change in speed at the junction of two blocks.
// This method will calculate the junction jerk as the euclidean distance between the nominal
// velocities of the respective blocks.
//inline float junction_jerk(block_t *before, block_t *after) {
// return sqrt(
// pow((before->speed_x-after->speed_x), 2)+pow((before->speed_y-after->speed_y), 2));
//}
// The kernel called by recalculate() when scanning the plan from last to first entry.
void Planner::reverse_pass_kernel(block_t* previous, block_t* current, block_t* next) {
if (!current) return;
UNUSED(previous);
if (next) {
// If entry speed is already at the maximum entry speed, no need to recheck. Block is cruising.
// If not, block in state of acceleration or deceleration. Reset entry speed to maximum and
// check for maximum allowable speed reductions to ensure maximum possible planned speed.
float max_entry_speed = current->max_entry_speed;
if (current->entry_speed != max_entry_speed) {
// If nominal length true, max junction speed is guaranteed to be reached. Only compute
// for max allowable speed if block is decelerating and nominal length is false.
if (!current->nominal_length_flag && max_entry_speed > next->entry_speed) {
current->entry_speed = min(max_entry_speed,
max_allowable_speed(-current->acceleration, next->entry_speed, current->millimeters));
}
else {
current->entry_speed = max_entry_speed;
}
current->recalculate_flag = true;
}
} // Skip last block. Already initialized and set for recalculation.
}
/**
* recalculate() needs to go over the current plan twice.
* Once in reverse and once forward. This implements the reverse pass.
*/
void Planner::reverse_pass() {
if (movesplanned() > 3) {
block_t* block[3] = { NULL, NULL, NULL };
// Make a local copy of block_buffer_tail, because the interrupt can alter it
CRITICAL_SECTION_START;
uint8_t tail = block_buffer_tail;
CRITICAL_SECTION_END
uint8_t b = BLOCK_MOD(block_buffer_head - 3);
while (b != tail) {
b = prev_block_index(b);
block[2] = block[1];
block[1] = block[0];
block[0] = &block_buffer[b];
reverse_pass_kernel(block[0], block[1], block[2]);
}
}
}
// The kernel called by recalculate() when scanning the plan from first to last entry.
void Planner::forward_pass_kernel(block_t* previous, block_t* current, block_t* next) {
if (!previous) return;
UNUSED(next);
// If the previous block is an acceleration block, but it is not long enough to complete the
// full speed change within the block, we need to adjust the entry speed accordingly. Entry
// speeds have already been reset, maximized, and reverse planned by reverse planner.
// If nominal length is true, max junction speed is guaranteed to be reached. No need to recheck.
if (!previous->nominal_length_flag) {
if (previous->entry_speed < current->entry_speed) {
double entry_speed = min(current->entry_speed,
max_allowable_speed(-previous->acceleration, previous->entry_speed, previous->millimeters));
// Check for junction speed change
if (current->entry_speed != entry_speed) {
current->entry_speed = entry_speed;
current->recalculate_flag = true;
}
}
}
}
/**
* recalculate() needs to go over the current plan twice.
* Once in reverse and once forward. This implements the forward pass.
*/
void Planner::forward_pass() {
block_t* block[3] = { NULL, NULL, NULL };
for (uint8_t b = block_buffer_tail; b != block_buffer_head; b = next_block_index(b)) {
block[0] = block[1];
block[1] = block[2];
block[2] = &block_buffer[b];
forward_pass_kernel(block[0], block[1], block[2]);
}
forward_pass_kernel(block[1], block[2], NULL);
}
/**
* Recalculate the trapezoid speed profiles for all blocks in the plan
* according to the entry_factor for each junction. Must be called by
* recalculate() after updating the blocks.
*/
void Planner::recalculate_trapezoids() {
int8_t block_index = block_buffer_tail;
block_t* current;
block_t* next = NULL;
while (block_index != block_buffer_head) {
current = next;
next = &block_buffer[block_index];
if (current) {
// Recalculate if current block entry or exit junction speed has changed.
if (current->recalculate_flag || next->recalculate_flag) {
// NOTE: Entry and exit factors always > 0 by all previous logic operations.
float nom = current->nominal_speed;
calculate_trapezoid_for_block(current, current->entry_speed / nom, next->entry_speed / nom);
current->recalculate_flag = false; // Reset current only to ensure next trapezoid is computed
}
}
block_index = next_block_index(block_index);
}
// Last/newest block in buffer. Exit speed is set with MINIMUM_PLANNER_SPEED. Always recalculated.
if (next) {
float nom = next->nominal_speed;
calculate_trapezoid_for_block(next, next->entry_speed / nom, (MINIMUM_PLANNER_SPEED) / nom);
next->recalculate_flag = false;
}
}
/*
* Recalculate the motion plan according to the following algorithm:
*
* 1. Go over every block in reverse order...
*
* Calculate a junction speed reduction (block_t.entry_factor) so:
*
* a. The junction jerk is within the set limit, and
*
* b. No speed reduction within one block requires faster
* deceleration than the one, true constant acceleration.
*
* 2. Go over every block in chronological order...
*
* Dial down junction speed reduction values if:
* a. The speed increase within one block would require faster
* acceleration than the one, true constant acceleration.
*
* After that, all blocks will have an entry_factor allowing all speed changes to
* be performed using only the one, true constant acceleration, and where no junction
* jerk is jerkier than the set limit, Jerky. Finally it will:
*
* 3. Recalculate "trapezoids" for all blocks.
*/
void Planner::recalculate() {
reverse_pass();
forward_pass();
recalculate_trapezoids();
}
#if ENABLED(AUTOTEMP)
void Planner::getHighESpeed() {
static float oldt = 0;
if (!autotemp_enabled) return;
if (thermalManager.degTargetHotend(0) + 2 < autotemp_min) return; // probably temperature set to zero.
float high = 0.0;
for (uint8_t b = block_buffer_tail; b != block_buffer_head; b = next_block_index(b)) {
block_t* block = &block_buffer[b];
if (block->steps[X_AXIS] || block->steps[Y_AXIS] || block->steps[Z_AXIS]) {
float se = (float)block->steps[E_AXIS] / block->step_event_count * block->nominal_speed; // mm/sec;
NOLESS(high, se);
}
}
float t = autotemp_min + high * autotemp_factor;
t = constrain(t, autotemp_min, autotemp_max);
if (oldt > t) {
t *= (1 - (AUTOTEMP_OLDWEIGHT));
t += (AUTOTEMP_OLDWEIGHT) * oldt;
}
oldt = t;
thermalManager.setTargetHotend(t, 0);
}
#endif //AUTOTEMP
/**
* Maintain fans, paste extruder pressure,
*/
void Planner::check_axes_activity() {
unsigned char axis_active[NUM_AXIS] = { 0 },
tail_fan_speed[FAN_COUNT];
#if FAN_COUNT > 0
for (uint8_t i = 0; i < FAN_COUNT; i++) tail_fan_speed[i] = fanSpeeds[i];
#endif
#if ENABLED(BARICUDA)
unsigned char tail_valve_pressure = baricuda_valve_pressure,
tail_e_to_p_pressure = baricuda_e_to_p_pressure;
#endif
if (blocks_queued()) {
#if FAN_COUNT > 0
for (uint8_t i = 0; i < FAN_COUNT; i++) tail_fan_speed[i] = block_buffer[block_buffer_tail].fan_speed[i];
#endif
block_t* block;
#if ENABLED(BARICUDA)
block = &block_buffer[block_buffer_tail];
tail_valve_pressure = block->valve_pressure;
tail_e_to_p_pressure = block->e_to_p_pressure;
#endif
for (uint8_t b = block_buffer_tail; b != block_buffer_head; b = next_block_index(b)) {
block = &block_buffer[b];
for (int i = 0; i < NUM_AXIS; i++) if (block->steps[i]) axis_active[i]++;
}
}
#if ENABLED(DISABLE_X)
if (!axis_active[X_AXIS]) disable_x();
#endif
#if ENABLED(DISABLE_Y)
if (!axis_active[Y_AXIS]) disable_y();
#endif
#if ENABLED(DISABLE_Z)
if (!axis_active[Z_AXIS]) disable_z();
#endif
#if ENABLED(DISABLE_E)
if (!axis_active[E_AXIS]) {
disable_e0();
disable_e1();
disable_e2();
disable_e3();
}
#endif
#if FAN_COUNT > 0
#if defined(FAN_MIN_PWM)
#define CALC_FAN_SPEED(f) (tail_fan_speed[f] ? ( FAN_MIN_PWM + (tail_fan_speed[f] * (255 - FAN_MIN_PWM)) / 255 ) : 0)
#else
#define CALC_FAN_SPEED(f) tail_fan_speed[f]
#endif
#ifdef FAN_KICKSTART_TIME
static millis_t fan_kick_end[FAN_COUNT] = { 0 };
#define KICKSTART_FAN(f) \
if (tail_fan_speed[f]) { \
millis_t ms = millis(); \
if (fan_kick_end[f] == 0) { \
fan_kick_end[f] = ms + FAN_KICKSTART_TIME; \
tail_fan_speed[f] = 255; \
} else { \
if (PENDING(ms, fan_kick_end[f])) { \
tail_fan_speed[f] = 255; \
} \
} \
} else { \
fan_kick_end[f] = 0; \
}
#if HAS_FAN0
KICKSTART_FAN(0);
#endif
#if HAS_FAN1
KICKSTART_FAN(1);
#endif
#if HAS_FAN2
KICKSTART_FAN(2);
#endif
#endif //FAN_KICKSTART_TIME
#if ENABLED(FAN_SOFT_PWM)
#if HAS_FAN0
thermalManager.fanSpeedSoftPwm[0] = CALC_FAN_SPEED(0);
#endif
#if HAS_FAN1
thermalManager.fanSpeedSoftPwm[1] = CALC_FAN_SPEED(1);
#endif
#if HAS_FAN2
thermalManager.fanSpeedSoftPwm[2] = CALC_FAN_SPEED(2);
#endif
#else
#if HAS_FAN0
analogWrite(FAN_PIN, CALC_FAN_SPEED(0));
#endif
#if HAS_FAN1
analogWrite(FAN1_PIN, CALC_FAN_SPEED(1));
#endif
#if HAS_FAN2
analogWrite(FAN2_PIN, CALC_FAN_SPEED(2));
#endif
#endif
#endif // FAN_COUNT > 0
#if ENABLED(AUTOTEMP)
getHighESpeed();
#endif
#if ENABLED(BARICUDA)
#if HAS_HEATER_1
analogWrite(HEATER_1_PIN, tail_valve_pressure);
#endif
#if HAS_HEATER_2
analogWrite(HEATER_2_PIN, tail_e_to_p_pressure);
#endif
#endif
}
/**
* Planner::buffer_line
*
* Add a new linear movement to the buffer.
*
* x,y,z,e - target position in mm
* feed_rate - (target) speed of the move
* extruder - target extruder
*/
#if ENABLED(AUTO_BED_LEVELING_FEATURE) || ENABLED(MESH_BED_LEVELING)
void Planner::buffer_line(float x, float y, float z, const float& e, float feed_rate, const uint8_t extruder)
#else
void Planner::buffer_line(const float& x, const float& y, const float& z, const float& e, float feed_rate, const uint8_t extruder)
#endif // AUTO_BED_LEVELING_FEATURE
{
// Calculate the buffer head after we push this byte
int next_buffer_head = next_block_index(block_buffer_head);
// If the buffer is full: good! That means we are well ahead of the robot.
// Rest here until there is room in the buffer.
while (block_buffer_tail == next_buffer_head) idle();
#if ENABLED(MESH_BED_LEVELING)
if (mbl.active())
z += mbl.get_z(x - home_offset[X_AXIS], y - home_offset[Y_AXIS]);
#elif ENABLED(AUTO_BED_LEVELING_FEATURE)
apply_rotation_xyz(bed_level_matrix, x, y, z);
#endif
// The target position of the tool in absolute steps
// Calculate target position in absolute steps
//this should be done after the wait, because otherwise a M92 code within the gcode disrupts this calculation somehow
long target[NUM_AXIS] = {
lround(x * axis_steps_per_mm[X_AXIS]),
lround(y * axis_steps_per_mm[Y_AXIS]),
lround(z * axis_steps_per_mm[Z_AXIS]),
lround(e * axis_steps_per_mm[E_AXIS])
};
long dx = target[X_AXIS] - position[X_AXIS],
dy = target[Y_AXIS] - position[Y_AXIS],
dz = target[Z_AXIS] - position[Z_AXIS];
// DRYRUN ignores all temperature constraints and assures that the extruder is instantly satisfied
if (DEBUGGING(DRYRUN))
position[E_AXIS] = target[E_AXIS];
long de = target[E_AXIS] - position[E_AXIS];
#if ENABLED(PREVENT_DANGEROUS_EXTRUDE)
if (de) {
if (thermalManager.tooColdToExtrude(extruder)) {
position[E_AXIS] = target[E_AXIS]; // Behave as if the move really took place, but ignore E part
de = 0; // no difference
SERIAL_ECHO_START;
SERIAL_ECHOLNPGM(MSG_ERR_COLD_EXTRUDE_STOP);
}
#if ENABLED(PREVENT_LENGTHY_EXTRUDE)
if (labs(de) > axis_steps_per_mm[E_AXIS] * (EXTRUDE_MAXLENGTH)) {
position[E_AXIS] = target[E_AXIS]; // Behave as if the move really took place, but ignore E part
de = 0; // no difference
SERIAL_ECHO_START;
SERIAL_ECHOLNPGM(MSG_ERR_LONG_EXTRUDE_STOP);
}
#endif
}
#endif
// Prepare to set up new block
block_t* block = &block_buffer[block_buffer_head];
// Mark block as not busy (Not executed by the stepper interrupt)
block->busy = false;
// Number of steps for each axis
#if ENABLED(COREXY)
// corexy planning
// these equations follow the form of the dA and dB equations on http://www.corexy.com/theory.html
block->steps[A_AXIS] = labs(dx + dy);
block->steps[B_AXIS] = labs(dx - dy);
block->steps[Z_AXIS] = labs(dz);
#elif ENABLED(COREXZ)
// corexz planning
block->steps[A_AXIS] = labs(dx + dz);
block->steps[Y_AXIS] = labs(dy);
block->steps[C_AXIS] = labs(dx - dz);
#elif ENABLED(COREYZ)
// coreyz planning
block->steps[X_AXIS] = labs(dx);
block->steps[B_AXIS] = labs(dy + dz);
block->steps[C_AXIS] = labs(dy - dz);
#else
// default non-h-bot planning
block->steps[X_AXIS] = labs(dx);
block->steps[Y_AXIS] = labs(dy);
block->steps[Z_AXIS] = labs(dz);
#endif
block->steps[E_AXIS] = labs(de);
block->steps[E_AXIS] *= volumetric_multiplier[extruder];
block->steps[E_AXIS] *= extruder_multiplier[extruder];
block->steps[E_AXIS] /= 100;
block->step_event_count = max(block->steps[X_AXIS], max(block->steps[Y_AXIS], max(block->steps[Z_AXIS], block->steps[E_AXIS])));
// Bail if this is a zero-length block
if (block->step_event_count <= dropsegments) return;
#if FAN_COUNT > 0
for (uint8_t i = 0; i < FAN_COUNT; i++) block->fan_speed[i] = fanSpeeds[i];
#endif
#if ENABLED(BARICUDA)
block->valve_pressure = baricuda_valve_pressure;
block->e_to_p_pressure = baricuda_e_to_p_pressure;
#endif
// Compute direction bits for this block
uint8_t db = 0;
#if ENABLED(COREXY)
if (dx < 0) SBI(db, X_HEAD); // Save the real Extruder (head) direction in X Axis
if (dy < 0) SBI(db, Y_HEAD); // ...and Y
if (dz < 0) SBI(db, Z_AXIS);
if (dx + dy < 0) SBI(db, A_AXIS); // Motor A direction
if (dx - dy < 0) SBI(db, B_AXIS); // Motor B direction
#elif ENABLED(COREXZ)
if (dx < 0) SBI(db, X_HEAD); // Save the real Extruder (head) direction in X Axis
if (dy < 0) SBI(db, Y_AXIS);
if (dz < 0) SBI(db, Z_HEAD); // ...and Z
if (dx + dz < 0) SBI(db, A_AXIS); // Motor A direction
if (dx - dz < 0) SBI(db, C_AXIS); // Motor C direction
#elif ENABLED(COREYZ)
if (dx < 0) SBI(db, X_AXIS);
if (dy < 0) SBI(db, Y_HEAD); // Save the real Extruder (head) direction in Y Axis
if (dz < 0) SBI(db, Z_HEAD); // ...and Z
if (dy + dz < 0) SBI(db, B_AXIS); // Motor B direction
if (dy - dz < 0) SBI(db, C_AXIS); // Motor C direction
#else
if (dx < 0) SBI(db, X_AXIS);
if (dy < 0) SBI(db, Y_AXIS);
if (dz < 0) SBI(db, Z_AXIS);
#endif
if (de < 0) SBI(db, E_AXIS);
block->direction_bits = db;
block->active_extruder = extruder;
//enable active axes
#if ENABLED(COREXY)
if (block->steps[A_AXIS] || block->steps[B_AXIS]) {
enable_x();
enable_y();
}
#if DISABLED(Z_LATE_ENABLE)
if (block->steps[Z_AXIS]) enable_z();
#endif
#elif ENABLED(COREXZ)
if (block->steps[A_AXIS] || block->steps[C_AXIS]) {
enable_x();
enable_z();
}
if (block->steps[Y_AXIS]) enable_y();
#else
if (block->steps[X_AXIS]) enable_x();
if (block->steps[Y_AXIS]) enable_y();
#if DISABLED(Z_LATE_ENABLE)
if (block->steps[Z_AXIS]) enable_z();
#endif
#endif
// Enable extruder(s)
if (block->steps[E_AXIS]) {
#if ENABLED(DISABLE_INACTIVE_EXTRUDER) // Enable only the selected extruder
for (int i = 0; i < EXTRUDERS; i++)
if (g_uc_extruder_last_move[i] > 0) g_uc_extruder_last_move[i]--;
switch(extruder) {
case 0:
enable_e0();
#if ENABLED(DUAL_X_CARRIAGE)
if (extruder_duplication_enabled) {
enable_e1();
g_uc_extruder_last_move[1] = (BLOCK_BUFFER_SIZE) * 2;
}
#endif
g_uc_extruder_last_move[0] = (BLOCK_BUFFER_SIZE) * 2;
#if EXTRUDERS > 1
if (g_uc_extruder_last_move[1] == 0) disable_e1();
#if EXTRUDERS > 2
if (g_uc_extruder_last_move[2] == 0) disable_e2();
#if EXTRUDERS > 3
if (g_uc_extruder_last_move[3] == 0) disable_e3();
#endif
#endif
#endif
break;
#if EXTRUDERS > 1
case 1:
enable_e1();
g_uc_extruder_last_move[1] = (BLOCK_BUFFER_SIZE) * 2;
if (g_uc_extruder_last_move[0] == 0) disable_e0();
#if EXTRUDERS > 2
if (g_uc_extruder_last_move[2] == 0) disable_e2();
#if EXTRUDERS > 3
if (g_uc_extruder_last_move[3] == 0) disable_e3();
#endif
#endif
break;
#if EXTRUDERS > 2
case 2:
enable_e2();
g_uc_extruder_last_move[2] = (BLOCK_BUFFER_SIZE) * 2;
if (g_uc_extruder_last_move[0] == 0) disable_e0();
if (g_uc_extruder_last_move[1] == 0) disable_e1();
#if EXTRUDERS > 3
if (g_uc_extruder_last_move[3] == 0) disable_e3();
#endif
break;
#if EXTRUDERS > 3
case 3:
enable_e3();
g_uc_extruder_last_move[3] = (BLOCK_BUFFER_SIZE) * 2;
if (g_uc_extruder_last_move[0] == 0) disable_e0();
if (g_uc_extruder_last_move[1] == 0) disable_e1();
if (g_uc_extruder_last_move[2] == 0) disable_e2();
break;
#endif // EXTRUDERS > 3
#endif // EXTRUDERS > 2
#endif // EXTRUDERS > 1
}
#else
enable_e0();
enable_e1();
enable_e2();
enable_e3();
#endif
}
if (block->steps[E_AXIS])
NOLESS(feed_rate, min_feedrate);
else
NOLESS(feed_rate, min_travel_feedrate);
/**
* This part of the code calculates the total length of the movement.
* For cartesian bots, the X_AXIS is the real X movement and same for Y_AXIS.
* But for corexy bots, that is not true. The "X_AXIS" and "Y_AXIS" motors (that should be named to A_AXIS
* and B_AXIS) cannot be used for X and Y length, because A=X+Y and B=X-Y.
* So we need to create other 2 "AXIS", named X_HEAD and Y_HEAD, meaning the real displacement of the Head.
* Having the real displacement of the head, we can calculate the total movement length and apply the desired speed.
*/
#if ENABLED(COREXY) || ENABLED(COREXZ) || ENABLED(COREYZ)
float delta_mm[6];
#if ENABLED(COREXY)
delta_mm[X_HEAD] = dx / axis_steps_per_mm[A_AXIS];
delta_mm[Y_HEAD] = dy / axis_steps_per_mm[B_AXIS];
delta_mm[Z_AXIS] = dz / axis_steps_per_mm[Z_AXIS];
delta_mm[A_AXIS] = (dx + dy) / axis_steps_per_mm[A_AXIS];
delta_mm[B_AXIS] = (dx - dy) / axis_steps_per_mm[B_AXIS];
#elif ENABLED(COREXZ)
delta_mm[X_HEAD] = dx / axis_steps_per_mm[A_AXIS];
delta_mm[Y_AXIS] = dy / axis_steps_per_mm[Y_AXIS];
delta_mm[Z_HEAD] = dz / axis_steps_per_mm[C_AXIS];
delta_mm[A_AXIS] = (dx + dz) / axis_steps_per_mm[A_AXIS];
delta_mm[C_AXIS] = (dx - dz) / axis_steps_per_mm[C_AXIS];
#elif ENABLED(COREYZ)
delta_mm[X_AXIS] = dx / axis_steps_per_mm[A_AXIS];
delta_mm[Y_HEAD] = dy / axis_steps_per_mm[Y_AXIS];
delta_mm[Z_HEAD] = dz / axis_steps_per_mm[C_AXIS];
delta_mm[B_AXIS] = (dy + dz) / axis_steps_per_mm[B_AXIS];
delta_mm[C_AXIS] = (dy - dz) / axis_steps_per_mm[C_AXIS];
#endif
#else
float delta_mm[4];
delta_mm[X_AXIS] = dx / axis_steps_per_mm[X_AXIS];
delta_mm[Y_AXIS] = dy / axis_steps_per_mm[Y_AXIS];
delta_mm[Z_AXIS] = dz / axis_steps_per_mm[Z_AXIS];
#endif
delta_mm[E_AXIS] = (de / axis_steps_per_mm[E_AXIS]) * volumetric_multiplier[extruder] * extruder_multiplier[extruder] / 100.0;
if (block->steps[X_AXIS] <= dropsegments && block->steps[Y_AXIS] <= dropsegments && block->steps[Z_AXIS] <= dropsegments) {
block->millimeters = fabs(delta_mm[E_AXIS]);
}
else {
block->millimeters = sqrt(
#if ENABLED(COREXY)
square(delta_mm[X_HEAD]) + square(delta_mm[Y_HEAD]) + square(delta_mm[Z_AXIS])
#elif ENABLED(COREXZ)
square(delta_mm[X_HEAD]) + square(delta_mm[Y_AXIS]) + square(delta_mm[Z_HEAD])
#elif ENABLED(COREYZ)
square(delta_mm[X_AXIS]) + square(delta_mm[Y_HEAD]) + square(delta_mm[Z_HEAD])
#else
square(delta_mm[X_AXIS]) + square(delta_mm[Y_AXIS]) + square(delta_mm[Z_AXIS])
#endif
);
}
float inverse_millimeters = 1.0 / block->millimeters; // Inverse millimeters to remove multiple divides
// Calculate moves/second for this move. No divide by zero due to previous checks.
float inverse_second = feed_rate * inverse_millimeters;
int moves_queued = movesplanned();
// Slow down when the buffer starts to empty, rather than wait at the corner for a buffer refill
#if ENABLED(OLD_SLOWDOWN) || ENABLED(SLOWDOWN)
bool mq = moves_queued > 1 && moves_queued < (BLOCK_BUFFER_SIZE) / 2;
#if ENABLED(OLD_SLOWDOWN)
if (mq) feed_rate *= 2.0 * moves_queued / (BLOCK_BUFFER_SIZE);
#endif
#if ENABLED(SLOWDOWN)
// segment time im micro seconds
unsigned long segment_time = lround(1000000.0/inverse_second);
if (mq) {
if (segment_time < min_segment_time) {
// buffer is draining, add extra time. The amount of time added increases if the buffer is still emptied more.
inverse_second = 1000000.0 / (segment_time + lround(2 * (min_segment_time - segment_time) / moves_queued));
#ifdef XY_FREQUENCY_LIMIT
segment_time = lround(1000000.0 / inverse_second);
#endif
}
}
#endif
#endif
block->nominal_speed = block->millimeters * inverse_second; // (mm/sec) Always > 0
block->nominal_rate = ceil(block->step_event_count * inverse_second); // (step/sec) Always > 0
#if ENABLED(FILAMENT_WIDTH_SENSOR)
static float filwidth_e_count = 0, filwidth_delay_dist = 0;
//FMM update ring buffer used for delay with filament measurements
if (extruder == FILAMENT_SENSOR_EXTRUDER_NUM && filwidth_delay_index2 >= 0) { //only for extruder with filament sensor and if ring buffer is initialized
const int MMD_CM = MAX_MEASUREMENT_DELAY + 1, MMD_MM = MMD_CM * 10;
// increment counters with next move in e axis
filwidth_e_count += delta_mm[E_AXIS];
filwidth_delay_dist += delta_mm[E_AXIS];
// Only get new measurements on forward E movement
if (filwidth_e_count > 0.0001) {
// Loop the delay distance counter (modulus by the mm length)
while (filwidth_delay_dist >= MMD_MM) filwidth_delay_dist -= MMD_MM;
// Convert into an index into the measurement array
filwidth_delay_index1 = (int)(filwidth_delay_dist / 10.0 + 0.0001);
// If the index has changed (must have gone forward)...
if (filwidth_delay_index1 != filwidth_delay_index2) {
filwidth_e_count = 0; // Reset the E movement counter
int8_t meas_sample = thermalManager.widthFil_to_size_ratio() - 100; // Subtract 100 to reduce magnitude - to store in a signed char
do {
filwidth_delay_index2 = (filwidth_delay_index2 + 1) % MMD_CM; // The next unused slot
measurement_delay[filwidth_delay_index2] = meas_sample; // Store the measurement
} while (filwidth_delay_index1 != filwidth_delay_index2); // More slots to fill?
}
}
}
#endif
// Calculate and limit speed in mm/sec for each axis
float current_speed[NUM_AXIS];
float speed_factor = 1.0; //factor <=1 do decrease speed
for (int i = 0; i < NUM_AXIS; i++) {
current_speed[i] = delta_mm[i] * inverse_second;
float cs = fabs(current_speed[i]), mf = max_feedrate[i];
if (cs > mf) speed_factor = min(speed_factor, mf / cs);
}
// Max segement time in us.
#ifdef XY_FREQUENCY_LIMIT
// Check and limit the xy direction change frequency
unsigned char direction_change = block->direction_bits ^ old_direction_bits;
old_direction_bits = block->direction_bits;
segment_time = lround((float)segment_time / speed_factor);
long xs0 = axis_segment_time[X_AXIS][0],
xs1 = axis_segment_time[X_AXIS][1],
xs2 = axis_segment_time[X_AXIS][2],
ys0 = axis_segment_time[Y_AXIS][0],
ys1 = axis_segment_time[Y_AXIS][1],
ys2 = axis_segment_time[Y_AXIS][2];
if (TEST(direction_change, X_AXIS)) {
xs2 = axis_segment_time[X_AXIS][2] = xs1;
xs1 = axis_segment_time[X_AXIS][1] = xs0;
xs0 = 0;
}
xs0 = axis_segment_time[X_AXIS][0] = xs0 + segment_time;
if (TEST(direction_change, Y_AXIS)) {
ys2 = axis_segment_time[Y_AXIS][2] = axis_segment_time[Y_AXIS][1];
ys1 = axis_segment_time[Y_AXIS][1] = axis_segment_time[Y_AXIS][0];
ys0 = 0;
}
ys0 = axis_segment_time[Y_AXIS][0] = ys0 + segment_time;
long max_x_segment_time = max(xs0, max(xs1, xs2)),
max_y_segment_time = max(ys0, max(ys1, ys2)),
min_xy_segment_time = min(max_x_segment_time, max_y_segment_time);
if (min_xy_segment_time < MAX_FREQ_TIME) {
float low_sf = speed_factor * min_xy_segment_time / (MAX_FREQ_TIME);
speed_factor = min(speed_factor, low_sf);
}
#endif // XY_FREQUENCY_LIMIT
// Correct the speed
if (speed_factor < 1.0) {
for (unsigned char i = 0; i < NUM_AXIS; i++) current_speed[i] *= speed_factor;
block->nominal_speed *= speed_factor;
block->nominal_rate *= speed_factor;
}
// Compute and limit the acceleration rate for the trapezoid generator.
float steps_per_mm = block->step_event_count / block->millimeters;
long bsx = block->steps[X_AXIS], bsy = block->steps[Y_AXIS], bsz = block->steps[Z_AXIS], bse = block->steps[E_AXIS];
if (bsx == 0 && bsy == 0 && bsz == 0) {
block->acceleration_steps_per_s2 = ceil(retract_acceleration * steps_per_mm); // convert to: acceleration steps/sec^2
}
else if (bse == 0) {
block->acceleration_steps_per_s2 = ceil(travel_acceleration * steps_per_mm); // convert to: acceleration steps/sec^2
}
else {
block->acceleration_steps_per_s2 = ceil(acceleration * steps_per_mm); // convert to: acceleration steps/sec^2
}
// Limit acceleration per axis
unsigned long acc_st = block->acceleration_steps_per_s2,
x_acc_st = max_acceleration_steps_per_s2[X_AXIS],
y_acc_st = max_acceleration_steps_per_s2[Y_AXIS],
z_acc_st = max_acceleration_steps_per_s2[Z_AXIS],
e_acc_st = max_acceleration_steps_per_s2[E_AXIS],
allsteps = block->step_event_count;
if (x_acc_st < (acc_st * bsx) / allsteps) acc_st = (x_acc_st * allsteps) / bsx;
if (y_acc_st < (acc_st * bsy) / allsteps) acc_st = (y_acc_st * allsteps) / bsy;
if (z_acc_st < (acc_st * bsz) / allsteps) acc_st = (z_acc_st * allsteps) / bsz;
if (e_acc_st < (acc_st * bse) / allsteps) acc_st = (e_acc_st * allsteps) / bse;
block->acceleration_steps_per_s2 = acc_st;
block->acceleration = acc_st / steps_per_mm;
block->acceleration_rate = (long)(acc_st * 16777216.0 / (F_CPU / 8.0));
#if 0 // Use old jerk for now
float junction_deviation = 0.1;
// Compute path unit vector
double unit_vec[3];
unit_vec[X_AXIS] = delta_mm[X_AXIS] * inverse_millimeters;
unit_vec[Y_AXIS] = delta_mm[Y_AXIS] * inverse_millimeters;
unit_vec[Z_AXIS] = delta_mm[Z_AXIS] * inverse_millimeters;
// Compute maximum allowable entry speed at junction by centripetal acceleration approximation.
// Let a circle be tangent to both previous and current path line segments, where the junction
// deviation is defined as the distance from the junction to the closest edge of the circle,
// collinear with the circle center. The circular segment joining the two paths represents the
// path of centripetal acceleration. Solve for max velocity based on max acceleration about the
// radius of the circle, defined indirectly by junction deviation. This may be also viewed as
// path width or max_jerk in the previous grbl version. This approach does not actually deviate
// from path, but used as a robust way to compute cornering speeds, as it takes into account the
// nonlinearities of both the junction angle and junction velocity.
double vmax_junction = MINIMUM_PLANNER_SPEED; // Set default max junction speed
// Skip first block or when previous_nominal_speed is used as a flag for homing and offset cycles.
if ((block_buffer_head != block_buffer_tail) && (previous_nominal_speed > 0.0)) {
// Compute cosine of angle between previous and current path. (prev_unit_vec is negative)
// NOTE: Max junction velocity is computed without sin() or acos() by trig half angle identity.
double cos_theta = - previous_unit_vec[X_AXIS] * unit_vec[X_AXIS]
- previous_unit_vec[Y_AXIS] * unit_vec[Y_AXIS]
- previous_unit_vec[Z_AXIS] * unit_vec[Z_AXIS] ;
// Skip and use default max junction speed for 0 degree acute junction.
if (cos_theta < 0.95) {
vmax_junction = min(previous_nominal_speed, block->nominal_speed);
// Skip and avoid divide by zero for straight junctions at 180 degrees. Limit to min() of nominal speeds.
if (cos_theta > -0.95) {
// Compute maximum junction velocity based on maximum acceleration and junction deviation
double sin_theta_d2 = sqrt(0.5 * (1.0 - cos_theta)); // Trig half angle identity. Always positive.
vmax_junction = min(vmax_junction,
sqrt(block->acceleration * junction_deviation * sin_theta_d2 / (1.0 - sin_theta_d2)));
}
}
}
#endif
// Start with a safe speed
float vmax_junction = max_xy_jerk / 2;
float vmax_junction_factor = 1.0;
float mz2 = max_z_jerk / 2, me2 = max_e_jerk / 2;
float csz = current_speed[Z_AXIS], cse = current_speed[E_AXIS];
if (fabs(csz) > mz2) vmax_junction = min(vmax_junction, mz2);
if (fabs(cse) > me2) vmax_junction = min(vmax_junction, me2);
vmax_junction = min(vmax_junction, block->nominal_speed);
float safe_speed = vmax_junction;
if ((moves_queued > 1) && (previous_nominal_speed > 0.0001)) {
float dsx = current_speed[X_AXIS] - previous_speed[X_AXIS],
dsy = current_speed[Y_AXIS] - previous_speed[Y_AXIS],
dsz = fabs(csz - previous_speed[Z_AXIS]),
dse = fabs(cse - previous_speed[E_AXIS]),
jerk = sqrt(dsx * dsx + dsy * dsy);
// if ((fabs(previous_speed[X_AXIS]) > 0.0001) || (fabs(previous_speed[Y_AXIS]) > 0.0001)) {
vmax_junction = block->nominal_speed;
// }
if (jerk > max_xy_jerk) vmax_junction_factor = max_xy_jerk / jerk;
if (dsz > max_z_jerk) vmax_junction_factor = min(vmax_junction_factor, max_z_jerk / dsz);
if (dse > max_e_jerk) vmax_junction_factor = min(vmax_junction_factor, max_e_jerk / dse);
vmax_junction = min(previous_nominal_speed, vmax_junction * vmax_junction_factor); // Limit speed to max previous speed
}
block->max_entry_speed = vmax_junction;
// Initialize block entry speed. Compute based on deceleration to user-defined MINIMUM_PLANNER_SPEED.
double v_allowable = max_allowable_speed(-block->acceleration, MINIMUM_PLANNER_SPEED, block->millimeters);
block->entry_speed = min(vmax_junction, v_allowable);
// Initialize planner efficiency flags
// Set flag if block will always reach maximum junction speed regardless of entry/exit speeds.
// If a block can de/ac-celerate from nominal speed to zero within the length of the block, then
// the current block and next block junction speeds are guaranteed to always be at their maximum
// junction speeds in deceleration and acceleration, respectively. This is due to how the current
// block nominal speed limits both the current and next maximum junction speeds. Hence, in both
// the reverse and forward planners, the corresponding block junction speed will always be at the
// the maximum junction speed and may always be ignored for any speed reduction checks.
block->nominal_length_flag = (block->nominal_speed <= v_allowable);
block->recalculate_flag = true; // Always calculate trapezoid for new block
// Update previous path unit_vector and nominal speed
for (int i = 0; i < NUM_AXIS; i++) previous_speed[i] = current_speed[i];
previous_nominal_speed = block->nominal_speed;
#if ENABLED(LIN_ADVANCE)
// bse == allsteps: A problem occurs when there's a very tiny move before a retract.
// In this case, the retract and the move will be executed together.
// This leads to an enormous number of advance steps due to a huge e_acceleration.
// The math is correct, but you don't want a retract move done with advance!
// So this situation is filtered out here.
if (!bse || (!bsx && !bsy && !bsz) || stepper.get_advance_k() == 0 || bse == allsteps) {
block->use_advance_lead = false;
}
else {
block->use_advance_lead = true;
block->e_speed_multiplier8 = (block->steps[E_AXIS] << 8) / block->step_event_count;
}
#elif ENABLED(ADVANCE)
// Calculate advance rate
if (!bse || (!bsx && !bsy && !bsz)) {
block->advance_rate = 0;
block->advance = 0;
}
else {
long acc_dist = estimate_acceleration_distance(0, block->nominal_rate, block->acceleration_steps_per_s2);
float advance = ((STEPS_PER_CUBIC_MM_E) * (EXTRUDER_ADVANCE_K)) * (cse * cse * (EXTRUSION_AREA) * (EXTRUSION_AREA)) * 256;
block->advance = advance;
block->advance_rate = acc_dist ? advance / (float)acc_dist : 0;
}
/**
SERIAL_ECHO_START;
SERIAL_ECHOPGM("advance :");
SERIAL_ECHO(block->advance/256.0);
SERIAL_ECHOPGM("advance rate :");
SERIAL_ECHOLN(block->advance_rate/256.0);
*/
#endif // ADVANCE or LIN_ADVANCE
calculate_trapezoid_for_block(block, block->entry_speed / block->nominal_speed, safe_speed / block->nominal_speed);
// Move buffer head
block_buffer_head = next_buffer_head;
// Update position
for (int i = 0; i < NUM_AXIS; i++) position[i] = target[i];
recalculate();
stepper.wake_up();
} // buffer_line()
#if ENABLED(AUTO_BED_LEVELING_FEATURE) && DISABLED(DELTA)
/**
* Get the XYZ position of the steppers as a vector_3.
*
* On CORE machines XYZ is derived from ABC.
*/
vector_3 Planner::adjusted_position() {
vector_3 pos = vector_3(stepper.get_axis_position_mm(X_AXIS), stepper.get_axis_position_mm(Y_AXIS), stepper.get_axis_position_mm(Z_AXIS));
//pos.debug("in Planner::adjusted_position");
//bed_level_matrix.debug("in Planner::adjusted_position");
matrix_3x3 inverse = matrix_3x3::transpose(bed_level_matrix);
//inverse.debug("in Planner::inverse");
pos.apply_rotation(inverse);
//pos.debug("after rotation");
return pos;
}
#endif // AUTO_BED_LEVELING_FEATURE && !DELTA
/**
* Directly set the planner XYZ position (hence the stepper positions).
*
* On CORE machines stepper ABC will be translated from the given XYZ.
*/
#if ENABLED(AUTO_BED_LEVELING_FEATURE) || ENABLED(MESH_BED_LEVELING)
void Planner::set_position_mm(float x, float y, float z, const float& e)
#else
void Planner::set_position_mm(const float& x, const float& y, const float& z, const float& e)
#endif // AUTO_BED_LEVELING_FEATURE || MESH_BED_LEVELING
{
#if ENABLED(MESH_BED_LEVELING)
if (mbl.active())
z += mbl.get_z(x - home_offset[X_AXIS], y - home_offset[Y_AXIS]);
#elif ENABLED(AUTO_BED_LEVELING_FEATURE)
apply_rotation_xyz(bed_level_matrix, x, y, z);
#endif
long nx = position[X_AXIS] = lround(x * axis_steps_per_mm[X_AXIS]),
ny = position[Y_AXIS] = lround(y * axis_steps_per_mm[Y_AXIS]),
nz = position[Z_AXIS] = lround(z * axis_steps_per_mm[Z_AXIS]),
ne = position[E_AXIS] = lround(e * axis_steps_per_mm[E_AXIS]);
stepper.set_position(nx, ny, nz, ne);
previous_nominal_speed = 0.0; // Resets planner junction speeds. Assumes start from rest.
for (int i = 0; i < NUM_AXIS; i++) previous_speed[i] = 0.0;
}
/**
* Directly set the planner E position (hence the stepper E position).
*/
void Planner::set_e_position_mm(const float& e) {
position[E_AXIS] = lround(e * axis_steps_per_mm[E_AXIS]);
stepper.set_e_position(position[E_AXIS]);
}
// Recalculate the steps/s^2 acceleration rates, based on the mm/s^2
void Planner::reset_acceleration_rates() {
for (int i = 0; i < NUM_AXIS; i++)
max_acceleration_steps_per_s2[i] = max_acceleration_mm_per_s2[i] * axis_steps_per_mm[i];
}
#if ENABLED(AUTOTEMP)
void Planner::autotemp_M109() {
autotemp_enabled = code_seen('F');
if (autotemp_enabled) autotemp_factor = code_value_temp_diff();
if (code_seen('S')) autotemp_min = code_value_temp_abs();
if (code_seen('B')) autotemp_max = code_value_temp_abs();
}
#endif
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