klipper-dgus/klippy/homing.py

148 lines
6.4 KiB
Python

# Code for state tracking during homing operations
#
# Copyright (C) 2016,2017 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import logging, math
HOMING_STEP_DELAY = 0.00000025
ENDSTOP_SAMPLE_TIME = .000015
ENDSTOP_SAMPLE_COUNT = 4
class Homing:
def __init__(self, toolhead):
self.toolhead = toolhead
self.changed_axes = []
self.verify_retract = True
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 _get_homing_speed(self, speed, endstops):
# Round the requested homing speed so that it is an even
# number of ticks per step.
mcu_stepper = endstops[0][0].get_steppers()[0]
adjusted_freq = mcu_stepper.get_mcu().get_adjusted_freq()
dist_ticks = adjusted_freq * mcu_stepper.get_step_dist()
ticks_per_step = math.ceil(dist_ticks / speed)
return dist_ticks / ticks_per_step
def homing_move(self, movepos, endstops, speed, dwell_t=0.,
probe_pos=False, verify_movement=False):
# Notify endstops of upcoming home
for mcu_endstop, name in endstops:
mcu_endstop.home_prepare()
if dwell_t:
self.toolhead.dwell(dwell_t, check_stall=False)
# Start endstop checking
print_time = self.toolhead.get_last_move_time()
start_mcu_pos = [(s, name, s.get_mcu_position())
for es, name in endstops for s in es.get_steppers()]
for mcu_endstop, name in endstops:
min_step_dist = min([s.get_step_dist()
for s in mcu_endstop.get_steppers()])
mcu_endstop.home_start(
print_time, ENDSTOP_SAMPLE_TIME, ENDSTOP_SAMPLE_COUNT,
min_step_dist / speed)
# Issue move
error = None
try:
self.toolhead.move(movepos, speed)
except EndstopError 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()
self.toolhead.reset_print_time(print_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))
if probe_pos:
self.set_homed_position(
list(self.toolhead.get_kinematics().calc_position()) + [None])
else:
self.toolhead.set_position(movepos)
for mcu_endstop, name in endstops:
mcu_endstop.home_finalize()
if error is not None:
raise EndstopError(error)
# Check if some movement occurred
if verify_movement:
for s, name, pos in start_mcu_pos:
if s.get_mcu_position() == pos:
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, limit_speed=None):
# 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)
# Determine homing speed
endstops = [es for rail in rails for es in rail.get_endstops()]
hi = rails[0].get_homing_info()
max_velocity = self.toolhead.get_max_velocity()[0]
if limit_speed is not None and limit_speed < max_velocity:
max_velocity = limit_speed
homing_speed = min(hi.speed, max_velocity)
homing_speed = self._get_homing_speed(homing_speed, endstops)
second_homing_speed = min(hi.second_homing_speed, max_velocity)
# Calculate a CPU delay when homing a large axis
axes_d = [mp - fp for mp, fp in zip(movepos, forcepos)]
est_move_d = abs(axes_d[0]) + abs(axes_d[1]) + abs(axes_d[2])
est_steps = sum([est_move_d / s.get_step_dist()
for es, n in endstops for s in es.get_steppers()])
dwell_t = est_steps * HOMING_STEP_DELAY
# Perform first home
self.homing_move(movepos, endstops, homing_speed, dwell_t=dwell_t)
# Perform second home
if hi.retract_dist:
# Retract
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, homing_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, second_homing_speed,
verify_movement=self.verify_retract)
# Apply homing offsets
for rail in rails:
cp = rail.get_commanded_position()
rail.set_commanded_position(cp + rail.get_homed_offset())
adjustpos = self.toolhead.get_kinematics().calc_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 EndstopError:
self.toolhead.motor_off()
raise
class EndstopError(Exception):
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]))