klipper/klippy/extras/homing.py

216 lines
9.3 KiB
Python

# Helper code for implementing homing operations
#
# Copyright (C) 2016-2021 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
# Return a completion that completes when all completions in a list complete
def multi_complete(printer, completions):
if len(completions) == 1:
return completions[0]
# Build completion that waits for all completions
reactor = printer.get_reactor()
cp = reactor.register_callback(lambda e: [c.wait() for c in completions])
# If any completion indicates an error, then exit main completion early
for c in completions:
reactor.register_callback(lambda e: cp.complete(1) if c.wait() else 0)
return cp
# Implementation of homing/probing moves
class HomingMove:
def __init__(self, printer, endstops, toolhead=None):
self.printer = printer
self.endstops = endstops
if toolhead is None:
toolhead = printer.lookup_object('toolhead')
self.toolhead = toolhead
self.end_mcu_pos = []
def get_mcu_endstops(self):
return [es for es, name in self.endstops]
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()])
if max_steps <= 0.:
return .001
return move_t / max_steps
def homing_move(self, movepos, speed, probe_pos=False,
triggered=True, check_triggered=True):
# Notify start of homing/probing move
self.printer.send_event("homing:homing_move_begin", self)
# Note start location
self.toolhead.flush_step_generation()
kin = self.toolhead.get_kinematics()
kin_spos = {s.get_name(): s.get_commanded_position()
for s in kin.get_steppers()}
start_mcu_pos = [(s, name, s.get_mcu_position())
for es, name in self.endstops
for s in es.get_steppers()]
# Start endstop checking
print_time = self.toolhead.get_last_move_time()
endstop_triggers = []
for mcu_endstop, name in self.endstops:
rest_time = self._calc_endstop_rate(mcu_endstop, movepos, speed)
wait = mcu_endstop.home_start(print_time, ENDSTOP_SAMPLE_TIME,
ENDSTOP_SAMPLE_COUNT, rest_time,
triggered=triggered)
endstop_triggers.append(wait)
all_endstop_trigger = multi_complete(self.printer, endstop_triggers)
self.toolhead.dwell(HOMING_START_DELAY)
# Issue move
error = None
try:
self.toolhead.drip_move(movepos, speed, all_endstop_trigger)
except self.printer.command_error 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 self.endstops:
did_trigger = mcu_endstop.home_wait(move_end_print_time)
if not did_trigger and check_triggered and error is None:
error = "Failed to home %s: Timeout during homing" % (name,)
# Determine stepper halt positions
self.toolhead.flush_step_generation()
self.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 self.end_mcu_pos:
sname = s.get_name()
if sname in kin_spos:
kin_spos[sname] += (epos - spos) * s.get_step_dist()
movepos = list(kin.calc_position(kin_spos))[:3] + movepos[3:]
self.toolhead.set_position(movepos)
# Signal homing/probing move complete
try:
self.printer.send_event("homing:homing_move_end", self)
except self.printer.command_error as e:
if error is None:
error = str(e)
if error is not None:
raise self.printer.command_error(error)
return movepos
def check_no_movement(self):
if self.printer.get_start_args().get('debuginput') is not None:
return None
for s, name, spos, epos in self.end_mcu_pos:
if spos == epos:
return name
return None
# State tracking of homing requests
class Homing:
def __init__(self, printer):
self.printer = printer
self.toolhead = printer.lookup_object('toolhead')
self.changed_axes = []
self.kin_spos = {}
def set_axes(self, axes):
self.changed_axes = axes
def get_axes(self):
return self.changed_axes
def get_stepper_trigger_positions(self):
return self.kin_spos
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 home_rails(self, rails, forcepos, movepos):
# Notify of upcoming homing operation
self.printer.send_event("homing:home_rails_begin", self, rails)
# 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()
hmove = HomingMove(self.printer, endstops)
hmove.homing_move(movepos, 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.retract_speed)
# Home again
forcepos = [rp - ad * retract_r
for rp, ad in zip(retractpos, axes_d)]
self.toolhead.set_position(forcepos)
hmove = HomingMove(self.printer, endstops)
hmove.homing_move(movepos, hi.second_homing_speed)
if hmove.check_no_movement() is not None:
raise self.printer.command_error(
"Endstop %s still triggered after retract"
% (hmove.check_no_movement(),))
# Signal home operation complete
self.toolhead.flush_step_generation()
kin = self.toolhead.get_kinematics()
kin_spos = {s.get_name(): s.get_commanded_position()
for s in kin.get_steppers()}
self.kin_spos = dict(kin_spos)
self.printer.send_event("homing:home_rails_end", self, rails)
if kin_spos != self.kin_spos:
# Apply any homing offsets
adjustpos = kin.calc_position(self.kin_spos)
for axis in homing_axes:
movepos[axis] = adjustpos[axis]
self.toolhead.set_position(movepos)
class PrinterHoming:
def __init__(self, config):
self.printer = config.get_printer()
# Register g-code commands
gcode = self.printer.lookup_object('gcode')
gcode.register_command('G28', self.cmd_G28)
def manual_home(self, toolhead, endstops, pos, speed,
triggered, check_triggered):
hmove = HomingMove(self.printer, endstops, toolhead)
hmove.homing_move(pos, speed, triggered=triggered,
check_triggered=check_triggered)
def probing_move(self, mcu_probe, pos, speed):
endstops = [(mcu_probe, "probe")]
hmove = HomingMove(self.printer, endstops)
epos = hmove.homing_move(pos, speed, probe_pos=True)
if hmove.check_no_movement() is not None:
raise self.printer.command_error(
"Probe triggered prior to movement")
return epos
def cmd_G28(self, gcmd):
# Move to origin
axes = []
for pos, axis in enumerate('XYZ'):
if gcmd.get(axis, None) is not None:
axes.append(pos)
if not axes:
axes = [0, 1, 2]
homing_state = Homing(self.printer)
homing_state.set_axes(axes)
kin = self.printer.lookup_object('toolhead').get_kinematics()
try:
kin.home(homing_state)
except self.printer.command_error:
self.printer.lookup_object('stepper_enable').motor_off()
raise
def load_config(config):
return PrinterHoming(config)