diff --git a/config/example-delta.cfg b/config/example-delta.cfg
index 3ae4c3120..76d0cfc07 100644
--- a/config/example-delta.cfg
+++ b/config/example-delta.cfg
@@ -107,3 +107,28 @@ delta_radius: 174.75
# axis towers. This parameter may also be calculated as:
# delta_radius = smooth_rod_offset - effector_offset - carriage_offset
# This parameter must be provided.
+
+# The delta_calibrate section enables a DELTA_CALIBRATE extended
+# g-code command that can calibrate the tower endstop positions and
+# angles.
+[delta_calibrate]
+radius: 50
+# Radius (in mm) of the area that may be probed. This is typically
+# the size of the printer bed. This parameter must be provided.
+#speed: 50
+# The speed (in mm/s) of non-probing moves during the
+# calibration. The default is 50.
+#horizontal_move_z: 5
+# The height (in mm) that the head should be commanded to move to
+# just prior to starting a probe operation. The default is 5.
+#probe_z_offset: 0
+# The Z height (in mm) of the head when the probe triggers. The
+# default is 0.
+#manual_probe:
+# If true, then DELTA_CALIBRATE will perform manual probing. If
+# false, then a PROBE command will be run at each probe
+# point. Manual probing is accomplished by manually jogging the Z
+# position of the print head at each probe point and then issuing a
+# NEXT extended g-code command to record the position at that
+# point. The default is false if a [probe] config section is present
+# and true otherwise.
diff --git a/klippy/delta.py b/klippy/delta.py
index 6d2490e59..7a294833d 100644
--- a/klippy/delta.py
+++ b/klippy/delta.py
@@ -24,10 +24,11 @@ class DeltaKinematics:
default_position=stepper_a.position_endstop)
self.steppers = [stepper_a, stepper_b, stepper_c]
self.need_motor_enable = self.need_home = True
- radius = config.getfloat('delta_radius', above=0.)
+ self.radius = radius = config.getfloat('delta_radius', above=0.)
arm_length_a = stepper_configs[0].getfloat('arm_length', above=radius)
- arm_lengths = [sconfig.getfloat('arm_length', arm_length_a, above=radius)
- for sconfig in stepper_configs]
+ self.arm_lengths = arm_lengths = [
+ sconfig.getfloat('arm_length', arm_length_a, above=radius)
+ for sconfig in stepper_configs]
self.arm2 = [arm**2 for arm in arm_lengths]
self.endstops = [s.position_endstop + math.sqrt(arm2 - radius**2)
for s, arm2 in zip(self.steppers, self.arm2)]
@@ -48,11 +49,12 @@ class DeltaKinematics:
for s in self.steppers:
s.set_max_jerk(max_halt_velocity, self.max_accel)
# Determine tower locations in cartesian space
- angles = [sconfig.getfloat('angle', angle)
- for sconfig, angle in zip(stepper_configs, [210., 330., 90.])]
+ self.angles = [sconfig.getfloat('angle', angle)
+ for sconfig, angle in zip(stepper_configs,
+ [210., 330., 90.])]
self.towers = [(math.cos(math.radians(angle)) * radius,
math.sin(math.radians(angle)) * radius)
- for angle in angles]
+ for angle in self.angles]
# Find the point where an XY move could result in excessive
# tower movement
half_min_step_dist = min([s.step_dist for s in self.steppers]) * .5
@@ -77,30 +79,7 @@ class DeltaKinematics:
- (self.towers[i][1] - coord[1])**2) + coord[2]
for i in StepList]
def _actuator_to_cartesian(self, pos):
- # Find nozzle position using trilateration (see wikipedia)
- carriage1 = list(self.towers[0]) + [pos[0]]
- carriage2 = list(self.towers[1]) + [pos[1]]
- carriage3 = list(self.towers[2]) + [pos[2]]
-
- s21 = matrix_sub(carriage2, carriage1)
- s31 = matrix_sub(carriage3, carriage1)
-
- d = math.sqrt(matrix_magsq(s21))
- ex = matrix_mul(s21, 1. / d)
- i = matrix_dot(ex, s31)
- vect_ey = matrix_sub(s31, matrix_mul(ex, i))
- ey = matrix_mul(vect_ey, 1. / math.sqrt(matrix_magsq(vect_ey)))
- ez = matrix_cross(ex, ey)
- j = matrix_dot(ey, s31)
-
- x = (self.arm2[0] - self.arm2[1] + d**2) / (2. * d)
- y = (self.arm2[0] - self.arm2[2] - x**2 + (x-i)**2 + j**2) / (2. * j)
- z = -math.sqrt(self.arm2[0] - x**2 - y**2)
-
- ex_x = matrix_mul(ex, x)
- ey_y = matrix_mul(ey, y)
- ez_z = matrix_mul(ez, z)
- return matrix_add(carriage1, matrix_add(ex_x, matrix_add(ey_y, ez_z)))
+ return actuator_to_cartesian(self.towers, self.arm2, pos)
def get_position(self):
spos = [s.mcu_stepper.get_commanded_position() for s in self.steppers]
return self._actuator_to_cartesian(spos)
@@ -225,6 +204,21 @@ class DeltaKinematics:
if decel_d:
step_delta(move_time, decel_d, cruise_v, -accel,
vt_startz, vt_startxy_d, vt_arm_d, movez_r)
+ # Helper functions for DELTA_CALIBRATE script
+ def get_stable_position(self):
+ return [int((ep - s.mcu_stepper.get_commanded_position())
+ / s.mcu_stepper.get_step_dist() + .5)
+ * s.mcu_stepper.get_step_dist()
+ for ep, s in zip(self.endstops, self.steppers)]
+ def get_calibrate_params(self):
+ return {
+ 'endstop_a': self.steppers[0].position_endstop,
+ 'endstop_b': self.steppers[1].position_endstop,
+ 'endstop_c': self.steppers[2].position_endstop,
+ 'angle_a': self.angles[0], 'angle_b': self.angles[1],
+ 'angle_c': self.angles[2], 'radius': self.radius,
+ 'arm_a': self.arm_lengths[0], 'arm_b': self.arm_lengths[1],
+ 'arm_c': self.arm_lengths[2] }
######################################################################
@@ -250,3 +244,41 @@ def matrix_sub(m1, m2):
def matrix_mul(m1, s):
return [m1[0]*s, m1[1]*s, m1[2]*s]
+
+def actuator_to_cartesian(towers, arm2, pos):
+ # Find nozzle position using trilateration (see wikipedia)
+ carriage1 = list(towers[0]) + [pos[0]]
+ carriage2 = list(towers[1]) + [pos[1]]
+ carriage3 = list(towers[2]) + [pos[2]]
+
+ s21 = matrix_sub(carriage2, carriage1)
+ s31 = matrix_sub(carriage3, carriage1)
+
+ d = math.sqrt(matrix_magsq(s21))
+ ex = matrix_mul(s21, 1. / d)
+ i = matrix_dot(ex, s31)
+ vect_ey = matrix_sub(s31, matrix_mul(ex, i))
+ ey = matrix_mul(vect_ey, 1. / math.sqrt(matrix_magsq(vect_ey)))
+ ez = matrix_cross(ex, ey)
+ j = matrix_dot(ey, s31)
+
+ x = (arm2[0] - arm2[1] + d**2) / (2. * d)
+ y = (arm2[0] - arm2[2] - x**2 + (x-i)**2 + j**2) / (2. * j)
+ z = -math.sqrt(arm2[0] - x**2 - y**2)
+
+ ex_x = matrix_mul(ex, x)
+ ey_y = matrix_mul(ey, y)
+ ez_z = matrix_mul(ez, z)
+ return matrix_add(carriage1, matrix_add(ex_x, matrix_add(ey_y, ez_z)))
+
+def get_position_from_stable(spos, params):
+ angles = [params['angle_a'], params['angle_b'], params['angle_c']]
+ radius = params['radius']
+ radius2 = radius**2
+ towers = [(math.cos(angle) * radius, math.sin(angle) * radius)
+ for angle in map(math.radians, angles)]
+ arm2 = [a**2 for a in [params['arm_a'], params['arm_b'], params['arm_c']]]
+ endstops = [params['endstop_a'], params['endstop_b'], params['endstop_c']]
+ pos = [es + math.sqrt(a2 - radius2) - p
+ for es, a2, p in zip(endstops, arm2, spos)]
+ return actuator_to_cartesian(towers, arm2, pos)
diff --git a/klippy/extras/delta_calibrate.py b/klippy/extras/delta_calibrate.py
new file mode 100644
index 000000000..5c69aa8d6
--- /dev/null
+++ b/klippy/extras/delta_calibrate.py
@@ -0,0 +1,76 @@
+# Delta calibration support
+#
+# Copyright (C) 2017-2018 Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import math, logging
+import probe, delta
+
+class DeltaCalibrate:
+ def __init__(self, config):
+ self.printer = config.get_printer()
+ if config.getsection('printer').get('kinematics') != 'delta':
+ raise config.error("Delta calibrate is only for delta printers")
+ self.radius = config.getfloat('radius', above=0.)
+ self.speed = config.getfloat('speed', 50., above=0.)
+ self.horizontal_move_z = config.getfloat('horizontal_move_z', 5.)
+ self.probe_z_offset = config.getfloat('probe_z_offset', 0.)
+ self.manual_probe = config.getboolean('manual_probe', None)
+ if self.manual_probe is None:
+ self.manual_probe = not config.has_section('probe')
+ self.gcode = self.printer.lookup_object('gcode')
+ self.gcode.register_command(
+ 'DELTA_CALIBRATE', self.cmd_DELTA_CALIBRATE,
+ desc=self.cmd_DELTA_CALIBRATE_help)
+ cmd_DELTA_CALIBRATE_help = "Delta calibration script"
+ def cmd_DELTA_CALIBRATE(self, params):
+ # Setup probe points
+ points = [(0., 0.)]
+ scatter = [.95, .90, .85, .70, .75, .80]
+ for i in range(6):
+ r = math.radians(90. + 60. * i)
+ dist = self.radius * scatter[i]
+ points.append((math.cos(r) * dist, math.sin(r) * dist))
+ # Probe them
+ self.gcode.run_script("G28")
+ probe.ProbePointsHelper(self.printer, points, self.horizontal_move_z,
+ self.speed, self.manual_probe, self)
+ def get_position(self):
+ kin = self.printer.lookup_object('toolhead').get_kinematics()
+ return kin.get_stable_position()
+ def finalize(self, positions):
+ kin = self.printer.lookup_object('toolhead').get_kinematics()
+ logging.debug("Got: %s", positions)
+ params = kin.get_calibrate_params()
+ logging.debug("Params: %s", params)
+ adj_params = ('endstop_a', 'endstop_b', 'endstop_c', 'radius',
+ 'angle_a', 'angle_b')
+ def delta_errorfunc(params):
+ total_error = 0.
+ for spos in positions:
+ x, y, z = delta.get_position_from_stable(spos, params)
+ total_error += (z - self.probe_z_offset)**2
+ return total_error
+ new_params = probe.coordinate_descent(
+ adj_params, params, delta_errorfunc)
+ logging.debug("Got2: %s", new_params)
+ for spos in positions:
+ logging.debug("orig: %s new: %s",
+ delta.get_position_from_stable(spos, params),
+ delta.get_position_from_stable(spos, new_params))
+ self.gcode.respond_info(
+ "stepper_a: position_endstop: %.6f angle: %.6f\n"
+ "stepper_b: position_endstop: %.6f angle: %.6f\n"
+ "stepper_c: position_endstop: %.6f angle: %.6f\n"
+ "radius: %.6f\n"
+ "To use these parameters, update the printer config file with\n"
+ "the above and then issue a RESTART command" % (
+ new_params['endstop_a'], new_params['angle_a'],
+ new_params['endstop_b'], new_params['angle_b'],
+ new_params['endstop_c'], new_params['angle_c'],
+ new_params['radius']))
+
+def load_config(config):
+ if config.get_name() != 'delta_calibrate':
+ raise config.error("Invalid delta_calibrate config name")
+ return DeltaCalibrate(config)
diff --git a/klippy/extras/probe.py b/klippy/extras/probe.py
index 73bdfafaf..aeebf725c 100644
--- a/klippy/extras/probe.py
+++ b/klippy/extras/probe.py
@@ -3,6 +3,7 @@
# Copyright (C) 2017-2018 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
+import logging
import homing
class PrinterProbe:
@@ -48,6 +49,91 @@ class PrinterProbe:
self.gcode.respond_info(
"probe: %s" % (["open", "TRIGGERED"][not not res],))
+# Helper code that can probe a series of points and report the
+# position at each point.
+class ProbePointsHelper:
+ def __init__(self, printer, probe_points, horizontal_move_z, speed,
+ manual_probe, callback):
+ self.printer = printer
+ self.probe_points = probe_points
+ self.horizontal_move_z = horizontal_move_z
+ self.speed = speed
+ self.callback = callback
+ self.toolhead = self.printer.lookup_object('toolhead')
+ self.results = []
+ self.busy = True
+ self.gcode = self.printer.lookup_object('gcode')
+ self.gcode.register_command(
+ 'NEXT', self.cmd_NEXT, desc=self.cmd_NEXT_help)
+ # Begin probing
+ self.move_next()
+ if not manual_probe:
+ while self.busy:
+ self.gcode.run_script("PROBE")
+ self.cmd_NEXT({})
+ def move_next(self):
+ x, y = self.probe_points[len(self.results)]
+ curpos = self.toolhead.get_position()
+ curpos[0] = x
+ curpos[1] = y
+ curpos[2] = self.horizontal_move_z
+ self.toolhead.move(curpos, self.speed)
+ self.gcode.reset_last_position()
+ cmd_NEXT_help = "Move to the next XY position to probe"
+ def cmd_NEXT(self, params):
+ # Record current position
+ self.toolhead.wait_moves()
+ self.results.append(self.callback.get_position())
+ # Move to next position
+ curpos = self.toolhead.get_position()
+ curpos[2] = self.horizontal_move_z
+ self.toolhead.move(curpos, self.speed)
+ if len(self.results) == len(self.probe_points):
+ self.toolhead.get_last_move_time()
+ self.finalize(True)
+ return
+ self.move_next()
+ def finalize(self, success):
+ self.busy = False
+ self.gcode.reset_last_position()
+ self.gcode.register_command('NEXT', None)
+ if success:
+ self.callback.finalize(self.results)
+
+# Helper code that implements coordinate descent
+def coordinate_descent(adj_params, params, error_func):
+ # Define potential changes
+ params = dict(params)
+ dp = {param_name: 1. for param_name in adj_params}
+ # Calculate the error
+ best_err = error_func(params)
+
+ threshold = 0.00001
+ rounds = 0
+
+ while sum(dp.values()) > threshold and rounds < 10000:
+ rounds += 1
+ for param_name in adj_params:
+ orig = params[param_name]
+ params[param_name] = orig + dp[param_name]
+ err = error_func(params)
+ if err < best_err:
+ # There was some improvement
+ best_err = err
+ dp[param_name] *= 1.1
+ continue
+ params[param_name] = orig - dp[param_name]
+ err = error_func(params)
+ if err < best_err:
+ # There was some improvement
+ best_err = err
+ dp[param_name] *= 1.1
+ continue
+ params[param_name] = orig
+ dp[param_name] *= 0.9
+ logging.debug("best_err: %s rounds: %d", best_err, rounds)
+ return params
+
def load_config(config):
if config.get_name() != 'probe':
raise config.error("Invalid probe config name")