klipper-dgus/klippy/homing.py

167 lines
6.9 KiB
Python

# Code for state tracking during homing operations
#
# Copyright (C) 2016-2019 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import logging, math, collections
HOMING_START_DELAY = 0.001
ENDSTOP_SAMPLE_TIME = .000015
ENDSTOP_SAMPLE_COUNT = 4
class Homing:
def __init__(self, printer):
self.printer = printer
self.toolhead = printer.lookup_object('toolhead')
self.changed_axes = []
self.verify_retract = True
self.endstops_pending = -1
def set_no_verify_retract(self):
self.verify_retract = False
def set_axes(self, axes):
self.changed_axes = axes
def get_axes(self):
return self.changed_axes
def _fill_coord(self, coord):
# Fill in any None entries in 'coord' with current toolhead position
thcoord = list(self.toolhead.get_position())
for i in range(len(coord)):
if coord[i] is not None:
thcoord[i] = coord[i]
return thcoord
def set_homed_position(self, pos):
self.toolhead.set_position(self._fill_coord(pos))
def _calc_endstop_rate(self, mcu_endstop, movepos, speed):
startpos = self.toolhead.get_position()
axes_d = [mp - sp for mp, sp in zip(movepos, startpos)]
move_d = math.sqrt(sum([d*d for d in axes_d[:3]]))
move_t = move_d / speed
max_steps = max([(abs(s.calc_position_from_coord(startpos)
- s.calc_position_from_coord(movepos))
/ s.get_step_dist())
for s in mcu_endstop.get_steppers()])
return move_t / max_steps
def _endstop_notify(self):
self.endstops_pending -= 1
if not self.endstops_pending:
self.toolhead.signal_drip_mode_end()
def homing_move(self, movepos, endstops, speed,
probe_pos=False, verify_movement=False):
# Notify endstops of upcoming home
for mcu_endstop, name in endstops:
mcu_endstop.home_prepare()
# Note start location
self.toolhead.flush_step_generation()
kin = self.toolhead.get_kinematics()
for s in kin.get_steppers():
s.set_tag_position(s.get_commanded_position())
start_mcu_pos = [(s, name, s.get_mcu_position())
for es, name in endstops for s in es.get_steppers()]
# Start endstop checking
print_time = self.toolhead.get_last_move_time()
self.endstops_pending = len(endstops)
for mcu_endstop, name in endstops:
rest_time = self._calc_endstop_rate(mcu_endstop, movepos, speed)
mcu_endstop.home_start(
print_time, ENDSTOP_SAMPLE_TIME, ENDSTOP_SAMPLE_COUNT,
rest_time, notify=self._endstop_notify)
self.toolhead.dwell(HOMING_START_DELAY)
# Issue move
error = None
try:
self.toolhead.drip_move(movepos, speed)
except CommandError as e:
error = "Error during homing move: %s" % (str(e),)
# Wait for endstops to trigger
move_end_print_time = self.toolhead.get_last_move_time()
for mcu_endstop, name in endstops:
try:
mcu_endstop.home_wait(move_end_print_time)
except mcu_endstop.TimeoutError as e:
if error is None:
error = "Failed to home %s: %s" % (name, str(e))
# Determine stepper halt positions
self.toolhead.flush_step_generation()
end_mcu_pos = [(s, name, spos, s.get_mcu_position())
for s, name, spos in start_mcu_pos]
if probe_pos:
for s, name, spos, epos in end_mcu_pos:
md = (epos - spos) * s.get_step_dist()
s.set_tag_position(s.get_tag_position() + md)
self.set_homed_position(kin.calc_tag_position())
else:
self.toolhead.set_position(movepos)
# Signal homing complete
for mcu_endstop, name in endstops:
try:
mcu_endstop.home_finalize()
except CommandError as e:
if error is None:
error = str(e)
if error is not None:
raise CommandError(error)
# Check if some movement occurred
if verify_movement:
for s, name, spos, epos in end_mcu_pos:
if spos == epos:
if probe_pos:
raise EndstopError("Probe triggered prior to movement")
raise EndstopError(
"Endstop %s still triggered after retract" % (name,))
def home_rails(self, rails, forcepos, movepos):
# Alter kinematics class to think printer is at forcepos
homing_axes = [axis for axis in range(3) if forcepos[axis] is not None]
forcepos = self._fill_coord(forcepos)
movepos = self._fill_coord(movepos)
self.toolhead.set_position(forcepos, homing_axes=homing_axes)
# Perform first home
endstops = [es for rail in rails for es in rail.get_endstops()]
hi = rails[0].get_homing_info()
self.homing_move(movepos, endstops, hi.speed)
# Perform second home
if hi.retract_dist:
# Retract
axes_d = [mp - fp for mp, fp in zip(movepos, forcepos)]
move_d = math.sqrt(sum([d*d for d in axes_d[:3]]))
retract_r = min(1., hi.retract_dist / move_d)
retractpos = [mp - ad * retract_r
for mp, ad in zip(movepos, axes_d)]
self.toolhead.move(retractpos, hi.speed)
# Home again
forcepos = [rp - ad * retract_r
for rp, ad in zip(retractpos, axes_d)]
self.toolhead.set_position(forcepos)
self.homing_move(movepos, endstops, hi.second_homing_speed,
verify_movement=self.verify_retract)
# Signal home operation complete
self.toolhead.flush_step_generation()
kin = self.toolhead.get_kinematics()
for s in kin.get_steppers():
s.set_tag_position(s.get_commanded_position())
ret = self.printer.send_event("homing:homed_rails", self, rails)
if any(ret):
# Apply any homing offsets
adjustpos = kin.calc_tag_position()
for axis in homing_axes:
movepos[axis] = adjustpos[axis]
self.toolhead.set_position(movepos)
def home_axes(self, axes):
self.changed_axes = axes
try:
self.toolhead.get_kinematics().home(self)
except CommandError:
self.printer.lookup_object('stepper_enable').motor_off()
raise
class CommandError(Exception):
pass
class EndstopError(CommandError):
pass
def EndstopMoveError(pos, msg="Move out of range"):
return EndstopError("%s: %.3f %.3f %.3f [%.3f]" % (
msg, pos[0], pos[1], pos[2], pos[3]))
Coord = collections.namedtuple('Coord', ('x', 'y', 'z', 'e'))