muele-marlin/Marlin/src/feature/backlash.cpp
2022-05-07 15:58:30 -05:00

213 lines
7.7 KiB
C++

/**
* Marlin 3D Printer Firmware
* Copyright (c) 2020 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 <https://www.gnu.org/licenses/>.
*
*/
#include "../inc/MarlinConfigPre.h"
#if ENABLED(BACKLASH_COMPENSATION)
#include "backlash.h"
#include "../module/motion.h"
#include "../module/planner.h"
axis_bits_t Backlash::last_direction_bits;
xyz_long_t Backlash::residual_error{0};
#ifdef BACKLASH_DISTANCE_MM
#if ENABLED(BACKLASH_GCODE)
xyz_float_t Backlash::distance_mm = BACKLASH_DISTANCE_MM;
#else
const xyz_float_t Backlash::distance_mm = BACKLASH_DISTANCE_MM;
#endif
#endif
#if ENABLED(BACKLASH_GCODE)
uint8_t Backlash::correction = (BACKLASH_CORRECTION) * all_on;
#ifdef BACKLASH_SMOOTHING_MM
float Backlash::smoothing_mm = BACKLASH_SMOOTHING_MM;
#endif
#endif
#if ENABLED(MEASURE_BACKLASH_WHEN_PROBING)
xyz_float_t Backlash::measured_mm{0};
xyz_uint8_t Backlash::measured_count{0};
#endif
Backlash backlash;
/**
* To minimize seams in the printed part, backlash correction only adds
* steps to the current segment (instead of creating a new segment, which
* causes discontinuities and print artifacts).
*
* With a non-zero BACKLASH_SMOOTHING_MM value the backlash correction is
* spread over multiple segments, smoothing out artifacts even more.
*/
void Backlash::add_correction_steps(const int32_t &da, const int32_t &db, const int32_t &dc, const axis_bits_t dm, block_t * const block) {
axis_bits_t changed_dir = last_direction_bits ^ dm;
// Ignore direction change unless steps are taken in that direction
#if DISABLED(CORE_BACKLASH) || EITHER(MARKFORGED_XY, MARKFORGED_YX)
if (!da) CBI(changed_dir, X_AXIS);
if (!db) CBI(changed_dir, Y_AXIS);
if (!dc) CBI(changed_dir, Z_AXIS);
#elif CORE_IS_XY
if (!(da + db)) CBI(changed_dir, X_AXIS);
if (!(da - db)) CBI(changed_dir, Y_AXIS);
if (!dc) CBI(changed_dir, Z_AXIS);
#elif CORE_IS_XZ
if (!(da + dc)) CBI(changed_dir, X_AXIS);
if (!(da - dc)) CBI(changed_dir, Z_AXIS);
if (!db) CBI(changed_dir, Y_AXIS);
#elif CORE_IS_YZ
if (!(db + dc)) CBI(changed_dir, Y_AXIS);
if (!(db - dc)) CBI(changed_dir, Z_AXIS);
if (!da) CBI(changed_dir, X_AXIS);
#endif
last_direction_bits ^= changed_dir;
if (!correction && !residual_error) return;
#ifdef BACKLASH_SMOOTHING_MM
// The segment proportion is a value greater than 0.0 indicating how much residual_error
// is corrected for in this segment. The contribution is based on segment length and the
// smoothing distance. Since the computation of this proportion involves a floating point
// division, defer computation until needed.
float segment_proportion = 0;
#endif
const float f_corr = float(correction) / all_on;
LOOP_LINEAR_AXES(axis) {
if (distance_mm[axis]) {
const bool reverse = TEST(dm, axis);
// When an axis changes direction, add axis backlash to the residual error
if (TEST(changed_dir, axis))
residual_error[axis] += (reverse ? -f_corr : f_corr) * distance_mm[axis] * planner.settings.axis_steps_per_mm[axis];
// Decide how much of the residual error to correct in this segment
int32_t error_correction = residual_error[axis];
if (reverse != (error_correction < 0))
error_correction = 0; // Don't take up any backlash in this segment, as it would subtract steps
#ifdef BACKLASH_SMOOTHING_MM
if (error_correction && smoothing_mm != 0) {
// Take up a portion of the residual_error in this segment
if (segment_proportion == 0) segment_proportion = _MIN(1.0f, block->millimeters / smoothing_mm);
error_correction = CEIL(segment_proportion * error_correction);
}
#endif
// This correction reduces the residual error and adds block steps
if (error_correction) {
block->steps[axis] += ABS(error_correction);
#if ENABLED(CORE_BACKLASH)
switch (axis) {
case CORE_AXIS_1:
//block->steps[CORE_AXIS_2] += influence_distance_mm[axis] * planner.settings.axis_steps_per_mm[CORE_AXIS_2];
//SERIAL_ECHOLNPGM("CORE_AXIS_1 dir change. distance=", distance_mm[axis], " r.err=", residual_error[axis],
// " da=", da, " db=", db, " block->steps[axis]=", block->steps[axis], " err_corr=", error_correction);
break;
case CORE_AXIS_2:
//block->steps[CORE_AXIS_1] += influence_distance_mm[axis] * planner.settings.axis_steps_per_mm[CORE_AXIS_1];;
//SERIAL_ECHOLNPGM("CORE_AXIS_2 dir change. distance=", distance_mm[axis], " r.err=", residual_error[axis],
// " da=", da, " db=", db, " block->steps[axis]=", block->steps[axis], " err_corr=", error_correction);
break;
case NORMAL_AXIS: break;
}
residual_error[axis] = 0; // No residual_error needed for next CORE block, I think...
#else
residual_error[axis] -= error_correction;
#endif
}
}
}
}
int32_t Backlash::get_applied_steps(const AxisEnum axis) {
if (axis >= LINEAR_AXES) return 0;
const bool reverse = TEST(last_direction_bits, axis);
const int32_t residual_error_axis = residual_error[axis];
// At startup it is assumed the last move was forwards. So the applied
// steps will always be a non-positive number.
if (!reverse) return -residual_error_axis;
const float f_corr = float(correction) / all_on;
const int32_t full_error_axis = -f_corr * distance_mm[axis] * planner.settings.axis_steps_per_mm[axis];
return full_error_axis - residual_error_axis;
}
class Backlash::StepAdjuster {
xyz_long_t applied_steps;
public:
StepAdjuster() {
LOOP_LINEAR_AXES(axis) applied_steps[axis] = backlash.get_applied_steps((AxisEnum)axis);
}
~StepAdjuster() {
// after backlash compensation parameter changes, ensure applied step count does not change
LOOP_LINEAR_AXES(axis) residual_error[axis] += backlash.get_applied_steps((AxisEnum)axis) - applied_steps[axis];
}
};
void Backlash::set_correction_uint8(const uint8_t v) {
StepAdjuster adjuster;
correction = v;
}
void Backlash::set_distance_mm(const AxisEnum axis, const float v) {
StepAdjuster adjuster;
distance_mm[axis] = v;
}
#ifdef BACKLASH_SMOOTHING_MM
void Backlash::set_smoothing_mm(const float v) {
StepAdjuster adjuster;
smoothing_mm = v;
}
#endif
#if ENABLED(MEASURE_BACKLASH_WHEN_PROBING)
#include "../module/probe.h"
// Measure Z backlash by raising nozzle in increments until probe deactivates
void Backlash::measure_with_probe() {
if (measured_count.z == 255) return;
const float start_height = current_position.z;
while (current_position.z < (start_height + BACKLASH_MEASUREMENT_LIMIT) && PROBE_TRIGGERED())
do_blocking_move_to_z(current_position.z + BACKLASH_MEASUREMENT_RESOLUTION, MMM_TO_MMS(BACKLASH_MEASUREMENT_FEEDRATE));
// The backlash from all probe points is averaged, so count the number of measurements
measured_mm.z += current_position.z - start_height;
measured_count.z++;
}
#endif
#endif // BACKLASH_COMPENSATION