extruder: Convert to using iterative solver

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
This commit is contained in:
Kevin O'Connor 2018-06-13 16:53:25 -04:00
parent 7148ebd565
commit bbe53cf8e5
5 changed files with 104 additions and 74 deletions

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@ -16,7 +16,7 @@ COMPILE_CMD = ("gcc -Wall -g -O2 -shared -fPIC"
" -o %s %s")
SOURCE_FILES = [
'pyhelper.c', 'serialqueue.c', 'stepcompress.c', 'itersolve.c',
'kin_cartesian.c', 'kin_corexy.c', 'kin_delta.c',
'kin_cartesian.c', 'kin_corexy.c', 'kin_delta.c', 'kin_extruder.c'
]
DEST_LIB = "c_helper.so"
OTHER_FILES = [
@ -71,6 +71,14 @@ defs_kin_delta = """
, double tower_x, double tower_y);
"""
defs_kin_extruder = """
struct stepper_kinematics *extruder_stepper_alloc(void);
void extruder_move_fill(struct move *m, double print_time
, double accel_t, double cruise_t, double decel_t, double start_pos
, double start_v, double cruise_v, double accel
, double extra_accel_v, double extra_decel_v);
"""
defs_serialqueue = """
#define MESSAGE_MAX 64
struct pull_queue_message {
@ -109,7 +117,7 @@ defs_std = """
defs_all = [
defs_pyhelper, defs_serialqueue, defs_std, defs_stepcompress, defs_itersolve,
defs_kin_cartesian, defs_kin_corexy, defs_kin_delta
defs_kin_cartesian, defs_kin_corexy, defs_kin_delta, defs_kin_extruder
]
# Return the list of file modification times

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@ -17,19 +17,6 @@
* Kinematic moves
****************************************************************/
struct move_accel {
double c1, c2;
};
struct move {
double print_time, move_t;
double accel_t, cruise_t;
double cruise_start_d, decel_start_d;
double cruise_v;
struct move_accel accel, decel;
struct coord start_pos, axes_r;
};
struct move * __visible
move_alloc(void)
{
@ -80,7 +67,7 @@ move_eval_accel(struct move_accel *ma, double move_time)
}
// Return the distance moved given a time in a move
static double
inline double
move_get_distance(struct move *m, double move_time)
{
if (unlikely(move_time < m->accel_t))

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@ -7,12 +7,26 @@ struct coord {
double x, y, z;
};
struct move_accel {
double c1, c2;
};
struct move {
double print_time, move_t;
double accel_t, cruise_t;
double cruise_start_d, decel_start_d;
double cruise_v;
struct move_accel accel, decel;
struct coord start_pos, axes_r;
};
struct move *move_alloc(void);
void move_fill(struct move *m, double print_time
, double accel_t, double cruise_t, double decel_t
, double start_pos_x, double start_pos_y, double start_pos_z
, double axes_d_x, double axes_d_y, double axes_d_z
, double start_v, double cruise_v, double accel);
double move_get_distance(struct move *m, double move_time);
struct coord move_get_coord(struct move *m, double move_time);
struct stepper_kinematics;

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@ -0,0 +1,54 @@
// Extruder stepper pulse time generation
//
// Copyright (C) 2018 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include <stdlib.h> // malloc
#include <string.h> // memset
#include "compiler.h" // __visible
#include "itersolve.h" // struct stepper_kinematics
#include "pyhelper.h" // errorf
static double
extruder_calc_position(struct stepper_kinematics *sk, struct move *m
, double move_time)
{
return m->start_pos.x + move_get_distance(m, move_time);
}
struct stepper_kinematics * __visible
extruder_stepper_alloc(void)
{
struct stepper_kinematics *sk = malloc(sizeof(*sk));
memset(sk, 0, sizeof(*sk));
sk->calc_position = extruder_calc_position;
return sk;
}
// Populate a 'struct move' with an extruder velocity trapezoid
void __visible
extruder_move_fill(struct move *m, double print_time
, double accel_t, double cruise_t, double decel_t
, double start_pos
, double start_v, double cruise_v, double accel
, double extra_accel_v, double extra_decel_v)
{
// Setup velocity trapezoid
m->print_time = print_time;
m->move_t = accel_t + cruise_t + decel_t;
m->accel_t = accel_t;
m->cruise_t = cruise_t;
m->cruise_start_d = accel_t * (.5 * (cruise_v + start_v) + extra_accel_v);
m->decel_start_d = m->cruise_start_d + cruise_t * cruise_v;
// Setup for accel/cruise/decel phases
m->cruise_v = cruise_v;
m->accel.c1 = start_v + extra_accel_v;
m->accel.c2 = .5 * accel;
m->decel.c1 = cruise_v + extra_decel_v;
m->decel.c2 = -m->accel.c2;
// Setup start distance
m->start_pos.x = start_pos;
}

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@ -4,7 +4,7 @@
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import math, logging
import stepper, homing
import stepper, homing, chelper
EXTRUDE_DIFF_IGNORE = 1.02
@ -47,6 +47,13 @@ class PrinterExtruder:
'pressure_advance_lookahead_time', 0.010, minval=0.)
self.need_motor_enable = True
self.extrude_pos = 0.
# Setup iterative solver
ffi_main, ffi_lib = chelper.get_ffi()
self.cmove = ffi_main.gc(ffi_lib.move_alloc(), ffi_lib.free)
self.extruder_move_fill = ffi_lib.extruder_move_fill
sk = ffi_main.gc(ffi_lib.extruder_stepper_alloc(), ffi_lib.free)
self.stepper.setup_itersolve(sk)
# Setup SET_PRESSURE_ADVANCE command
gcode = self.printer.lookup_object('gcode')
if self.name in ('extruder', 'extruder0'):
gcode.register_mux_command("SET_PRESSURE_ADVANCE", "EXTRUDER", None,
@ -154,82 +161,42 @@ class PrinterExtruder:
self.stepper.motor_enable(print_time, 1)
self.need_motor_enable = False
axis_d = move.axes_d[3]
axis_r = abs(axis_d) / move.move_d
axis_r = axis_d / move.move_d
accel = move.accel * axis_r
start_v = move.start_v * axis_r
cruise_v = move.cruise_v * axis_r
end_v = move.end_v * axis_r
accel_t, cruise_t, decel_t = move.accel_t, move.cruise_t, move.decel_t
accel_d = move.accel_r * axis_d
cruise_d = move.cruise_r * axis_d
decel_d = move.decel_r * axis_d
retract_t = retract_d = retract_v = 0.
decel_v = cruise_v
# Update for pressure advance
extra_accel_v = extra_decel_v = 0.
start_pos = self.extrude_pos
if (axis_d >= 0. and (move.axes_d[0] or move.axes_d[1])
and self.pressure_advance):
# Increase accel_d and start_v when accelerating
# Calculate extra_accel_v
pressure_advance = self.pressure_advance * move.extrude_r
prev_pressure_d = start_pos - move.start_pos[3]
if accel_d:
if accel_t:
npd = move.cruise_v * pressure_advance
extra_accel_d = npd - prev_pressure_d
if extra_accel_d > 0.:
accel_d += extra_accel_d
start_v += extra_accel_d / accel_t
extra_accel_v = extra_accel_d / accel_t
axis_d += extra_accel_d
prev_pressure_d += extra_accel_d
# Update decel and retract parameters when decelerating
# Calculate extra_decel_v
emcv = move.extrude_max_corner_v
if decel_d and emcv < move.cruise_v:
if decel_t and emcv < move.cruise_v:
npd = max(emcv, move.end_v) * pressure_advance
extra_decel_d = prev_pressure_d - npd
if extra_decel_d > 0.:
extra_decel_d = npd - prev_pressure_d
if extra_decel_d < 0.:
axis_d += extra_decel_d
extra_decel_v = extra_decel_d / decel_t
decel_v -= extra_decel_v
end_v -= extra_decel_v
if decel_v <= 0.:
# The entire decel phase is replaced with retraction
retract_t = decel_t
retract_d = -(end_v + decel_v) * 0.5 * decel_t
retract_v = -decel_v
decel_t = decel_d = 0.
elif end_v < 0.:
# Split decel phase into decel and retraction
retract_t = -end_v / accel
retract_d = -end_v * 0.5 * retract_t
decel_t -= retract_t
decel_d = decel_v * 0.5 * decel_t
else:
# There is still only a decel phase (no retraction)
decel_d -= extra_decel_d
# Prepare for steps
step_const = self.stepper.step_const
move_time = print_time
# Acceleration steps
if accel_d:
step_const(move_time, start_pos, accel_d, start_v, accel)
start_pos += accel_d
move_time += accel_t
# Cruising steps
if cruise_d:
step_const(move_time, start_pos, cruise_d, cruise_v, 0.)
start_pos += cruise_d
move_time += cruise_t
# Deceleration steps
if decel_d:
step_const(move_time, start_pos, decel_d, decel_v, -accel)
start_pos += decel_d
move_time += decel_t
# Retraction steps
if retract_d:
step_const(move_time, start_pos, -retract_d, retract_v, accel)
start_pos -= retract_d
self.extrude_pos = start_pos
# Generate steps
self.extruder_move_fill(
self.cmove, print_time, accel_t, cruise_t, decel_t, start_pos,
start_v, cruise_v, accel, extra_accel_v, extra_decel_v)
self.stepper.step_itersolve(self.cmove)
self.extrude_pos = start_pos + axis_d
cmd_SET_PRESSURE_ADVANCE_help = "Set pressure advance parameters"
def cmd_default_SET_PRESSURE_ADVANCE(self, params):
extruder = self.printer.lookup_object('toolhead').get_extruder()