klipper-dgus/klippy/extruder.py

130 lines
5.4 KiB
Python

# Code for handling printer nozzle extruders
#
# Copyright (C) 2016 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import logging
import stepper, heater
class PrinterExtruder:
def __init__(self, printer, config):
cfg = config.getsection('extruder')
self.heater = heater.PrinterHeater(printer, cfg)
self.stepper = stepper.PrinterStepper(printer, cfg)
self.pressure_advance = config.getfloat('pressure_advance', 0.)
self.stepper_pos = 0
self.extrude_pos = 0.
def build_config(self):
self.heater.build_config()
self.stepper.set_max_jerk(9999999.9)
self.stepper.build_config()
def get_max_speed(self):
return self.stepper.max_velocity, self.stepper.max_accel
def motor_off(self, move_time):
self.stepper.motor_enable(move_time, 0)
def move(self, move_time, move):
move_d = move.move_d
inv_accel = 1. / move.accel
start_v, cruise_v, end_v = move.start_v, move.cruise_v, move.end_v
accel_t, cruise_t, decel_t = move.accel_t, move.cruise_t, move.decel_t
accel_d = move.accel_r * move_d
cruise_d = move.cruise_r * move_d
decel_d = move.decel_r * move_d
retract_t = retract_d = retract_v = 0.
decel_v = cruise_v
# Update for pressure advance
if (move.axes_d[3] >= 0. and (move.axes_d[0] or move.axes_d[1])
and self.pressure_advance):
# Increase accel_d and start_v when accelerating
extra_accel_d = (cruise_v - start_v) * self.pressure_advance
accel_d += extra_accel_d
if accel_t:
start_v += extra_accel_d / accel_t
# Update decel and retract parameters when decelerating
if decel_t:
extra_decel_d = (cruise_v - end_v) * self.pressure_advance
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 * inv_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
# Determine regular steps
extrude_r = move.axes_d[3] / move_d
forward_d = accel_d + cruise_d + decel_d
self.extrude_pos += forward_d * extrude_r
new_step_pos = int(self.extrude_pos*self.stepper.inv_step_dist + 0.5)
steps = new_step_pos - self.stepper_pos
if steps:
self.stepper_pos = new_step_pos
sdir = 0
if steps < 0:
sdir = 1
steps = -steps
mcu_time, so = self.stepper.prep_move(move_time, sdir)
step_dist = forward_d / steps
inv_step_dist = 1. / step_dist
step_offset = 0.5
# Acceleration steps
#t = sqrt(2*pos/accel + (start_v/accel)**2) - start_v/accel
accel_time_offset = start_v * inv_accel
accel_sqrt_offset = accel_time_offset**2
accel_multiplier = 2.0 * step_dist * inv_accel
accel_steps = accel_d * inv_step_dist
step_offset = so.step_sqrt(
mcu_time - accel_time_offset, accel_steps, step_offset
, accel_sqrt_offset, accel_multiplier)
mcu_time += accel_t
# Cruising steps
#t = pos/cruise_v
cruise_multiplier = step_dist / cruise_v
cruise_steps = cruise_d * inv_step_dist
step_offset = so.step_factor(
mcu_time, cruise_steps, step_offset, cruise_multiplier)
mcu_time += cruise_t
# Deceleration steps
#t = cruise_v/accel - sqrt((cruise_v/accel)**2 - 2*pos/accel)
decel_time_offset = decel_v * inv_accel
decel_sqrt_offset = decel_time_offset**2
decel_steps = decel_d * inv_step_dist
so.step_sqrt(
mcu_time + decel_time_offset, decel_steps, step_offset
, decel_sqrt_offset, -accel_multiplier)
# Determine retract steps
self.extrude_pos -= retract_d * extrude_r
new_step_pos = int(self.extrude_pos*self.stepper.inv_step_dist + 0.5)
steps = self.stepper_pos - new_step_pos
if steps:
self.stepper_pos = new_step_pos
mcu_time, so = self.stepper.prep_move(
move_time+accel_t+cruise_t+decel_t, 1)
step_dist = retract_d / steps
# Acceleration steps
#t = sqrt(2*pos/accel + (start_v/accel)**2) - start_v/accel
accel_time_offset = retract_v * inv_accel
accel_sqrt_offset = accel_time_offset**2
accel_multiplier = 2.0 * step_dist * inv_accel
so.step_sqrt(mcu_time - accel_time_offset, steps, 0.5
, accel_sqrt_offset, accel_multiplier)