klipper-dgus/klippy/extras/z_tilt.py

163 lines
7.1 KiB
Python

# Mechanical bed tilt calibration with multiple Z steppers
#
# Copyright (C) 2018-2019 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import logging
import probe, mathutil
class ZAdjustHelper:
def __init__(self, config, z_count):
self.printer = config.get_printer()
self.name = config.get_name()
self.z_count = z_count
self.z_steppers = []
self.printer.register_event_handler("klippy:connect",
self.handle_connect)
def handle_connect(self):
kin = self.printer.lookup_object('toolhead').get_kinematics()
z_steppers = kin.get_steppers('Z')
if len(z_steppers) != self.z_count:
raise self.printer.config_error(
"%s z_positions needs exactly %d items" % (
self.name, len(z_steppers)))
if len(z_steppers) < 2:
raise config.error("%s requires multiple z steppers" % (self.name,))
self.z_steppers = z_steppers
def adjust_steppers(self, adjustments, speed):
toolhead = self.printer.lookup_object('toolhead')
gcode = self.printer.lookup_object('gcode')
curpos = toolhead.get_position()
# Report on movements
stepstrs = ["%s = %.6f" % (s.get_name(), a)
for s, a in zip(self.z_steppers, adjustments)]
msg = "Making the following Z adjustments:\n%s" % ("\n".join(stepstrs),)
gcode.respond_info(msg)
# Disable Z stepper movements
for s in self.z_steppers:
s.set_ignore_move(True)
# Move each z stepper (sorted from lowest to highest) until they match
positions = [(-a, s) for a, s in zip(adjustments, self.z_steppers)]
positions.sort()
first_stepper_offset, first_stepper = positions[0]
z_low = curpos[2] - first_stepper_offset
for i in range(len(positions)-1):
stepper_offset, stepper = positions[i]
next_stepper_offset, next_stepper = positions[i+1]
stepper.set_ignore_move(False)
curpos[2] = z_low + next_stepper_offset
try:
toolhead.move(curpos, speed)
toolhead.set_position(curpos)
except:
logging.exception("ZAdjustHelper adjust_steppers")
for s in self.z_steppers:
s.set_ignore_move(False)
raise
# Z should now be level - do final cleanup
last_stepper_offset, last_stepper = positions[-1]
last_stepper.set_ignore_move(False)
curpos[2] += first_stepper_offset
toolhead.set_position(curpos)
gcode.reset_last_position()
class RetryHelper:
def __init__(self, config, error_msg_extra = ""):
self.gcode = config.get_printer().lookup_object('gcode')
self.default_max_retries = config.getint("retries", 0, minval=0)
self.default_retry_tolerance = \
config.getfloat("retry_tolerance", 0., above=0.)
self.value_label = "Probed points range"
self.error_msg_extra = error_msg_extra
def start(self, params):
self.max_retries = self.gcode.get_int('RETRIES', params,
default=self.default_max_retries, minval=0, maxval=30)
self.retry_tolerance = self.gcode.get_float('RETRY_TOLERANCE', params,
default=self.default_retry_tolerance, minval=0, maxval=1.0)
self.current_retry = 0
self.previous = None
self.increasing = 0
def check_increase(self,error):
if self.previous and error > self.previous + 0.0000001:
self.increasing += 1
elif self.increasing > 0:
self.increasing -= 1
self.previous = error
return self.increasing > 1
def check_retry(self,z_positions):
if self.max_retries == 0:
return
error = max(z_positions) - min(z_positions)
if self.check_increase(error):
self.gcode.respond_error(
"Retries aborting: %s is increasing. %s" % (
self.value_label, self.error_msg_extra))
return
self.gcode.respond_info(
"Retries: %d/%d %s: %0.6f tolerance: %0.6f" % (
self.current_retry, self.max_retries, self.value_label,
error, self.retry_tolerance))
if error <= self.retry_tolerance:
return "done"
self.current_retry += 1
if self.current_retry > self.max_retries:
self.gcode.respond_error("Too many retries")
return
return "retry"
class ZTilt:
def __init__(self, config):
self.printer = config.get_printer()
z_positions = config.get('z_positions').split('\n')
try:
z_positions = [line.split(',', 1)
for line in z_positions if line.strip()]
self.z_positions = [(float(zp[0].strip()), float(zp[1].strip()))
for zp in z_positions]
except:
raise config.error("Unable to parse z_positions in %s" % (
config.get_name()))
self.retry_helper = RetryHelper(config)
self.probe_helper = probe.ProbePointsHelper(config, self.probe_finalize)
self.probe_helper.minimum_points(2)
self.z_helper = ZAdjustHelper(config, len(self.z_positions))
# Register Z_TILT_ADJUST command
self.gcode = self.printer.lookup_object('gcode')
self.gcode.register_command('Z_TILT_ADJUST', self.cmd_Z_TILT_ADJUST,
desc=self.cmd_Z_TILT_ADJUST_help)
cmd_Z_TILT_ADJUST_help = "Adjust the Z tilt"
def cmd_Z_TILT_ADJUST(self, params):
self.retry_helper.start(params)
self.probe_helper.start_probe(params)
def probe_finalize(self, offsets, positions):
# Setup for coordinate descent analysis
z_offset = offsets[2]
logging.info("Calculating bed tilt with: %s", positions)
params = { 'x_adjust': 0., 'y_adjust': 0., 'z_adjust': z_offset }
# Perform coordinate descent
def adjusted_height(pos, params):
x, y, z = pos
return (z - x*params['x_adjust'] - y*params['y_adjust']
- params['z_adjust'])
def errorfunc(params):
total_error = 0.
for pos in positions:
total_error += adjusted_height(pos, params)**2
return total_error
new_params = mathutil.coordinate_descent(
params.keys(), params, errorfunc)
# Apply results
speed = self.probe_helper.get_lift_speed()
logging.info("Calculated bed tilt parameters: %s", new_params)
x_adjust = new_params['x_adjust']
y_adjust = new_params['y_adjust']
z_adjust = (new_params['z_adjust'] - z_offset
- x_adjust * offsets[0] - y_adjust * offsets[1])
adjustments = [x*x_adjust + y*y_adjust + z_adjust
for x, y in self.z_positions]
self.z_helper.adjust_steppers(adjustments, speed)
return self.retry_helper.check_retry([p[2] for p in positions])
def load_config(config):
return ZTilt(config)