klipper/klippy/kinematics/cartesian.py

168 lines
7.5 KiB
Python

# Code for handling the kinematics of cartesian robots
#
# Copyright (C) 2016-2018 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import logging
import stepper, homing
class CartKinematics:
def __init__(self, toolhead, config):
self.printer = config.get_printer()
# Setup axis rails
self.rails = [stepper.LookupMultiRail(config.getsection('stepper_' + n))
for n in ['x', 'y', 'z']]
for rail, axis in zip(self.rails, 'xyz'):
rail.setup_itersolve('cartesian_stepper_alloc', axis)
# Setup boundary checks
max_velocity, max_accel = toolhead.get_max_velocity()
self.max_z_velocity = config.getfloat(
'max_z_velocity', max_velocity, above=0., maxval=max_velocity)
self.max_z_accel = config.getfloat(
'max_z_accel', max_accel, above=0., maxval=max_accel)
self.need_motor_enable = True
self.limits = [(1.0, -1.0)] * 3
# Setup stepper max halt velocity
max_halt_velocity = toolhead.get_max_axis_halt()
self.rails[0].set_max_jerk(max_halt_velocity, max_accel)
self.rails[1].set_max_jerk(max_halt_velocity, max_accel)
self.rails[2].set_max_jerk(
min(max_halt_velocity, self.max_z_velocity), max_accel)
# Check for dual carriage support
self.dual_carriage_axis = None
self.dual_carriage_rails = []
if config.has_section('dual_carriage'):
dc_config = config.getsection('dual_carriage')
dc_axis = dc_config.getchoice('axis', {'x': 'x', 'y': 'y'})
self.dual_carriage_axis = {'x': 0, 'y': 1}[dc_axis]
dc_rail = stepper.LookupMultiRail(dc_config)
dc_rail.setup_itersolve('cartesian_stepper_alloc', dc_axis)
dc_rail.set_max_jerk(max_halt_velocity, max_accel)
self.dual_carriage_rails = [
self.rails[self.dual_carriage_axis], dc_rail]
self.printer.lookup_object('gcode').register_command(
'SET_DUAL_CARRIAGE', self.cmd_SET_DUAL_CARRIAGE,
desc=self.cmd_SET_DUAL_CARRIAGE_help)
def get_steppers(self, flags=""):
if flags == "Z":
return self.rails[2].get_steppers()
return [s for rail in self.rails for s in rail.get_steppers()]
def calc_position(self):
return [rail.get_commanded_position() for rail in self.rails]
def set_position(self, newpos, homing_axes):
for i, rail in enumerate(self.rails):
rail.set_position(newpos)
if i in homing_axes:
self.limits[i] = rail.get_range()
def _home_axis(self, homing_state, axis, rail):
# Determine moves
position_min, position_max = rail.get_range()
hi = rail.get_homing_info()
if hi.positive_dir:
pos = hi.position_endstop - 1.5*(hi.position_endstop - position_min)
rpos = hi.position_endstop - hi.retract_dist
r2pos = rpos - hi.retract_dist
else:
pos = hi.position_endstop + 1.5*(position_max - hi.position_endstop)
rpos = hi.position_endstop + hi.retract_dist
r2pos = rpos + hi.retract_dist
# Initial homing
homing_speed = hi.speed
second_homing_speed = hi.second_homing_speed
if axis == 2:
homing_speed = min(homing_speed, self.max_z_velocity)
second_homing_speed = min(second_homing_speed, self.max_z_velocity)
homepos = [None, None, None, None]
homepos[axis] = hi.position_endstop
coord = [None, None, None, None]
coord[axis] = pos
homing_state.home(coord, homepos, rail.get_endstops(), homing_speed)
# Retract
coord[axis] = rpos
homing_state.retract(coord, second_homing_speed)
# Home again
coord[axis] = r2pos
homing_state.home(coord, homepos, rail.get_endstops(),
second_homing_speed, second_home=True)
# Set final homed position
coord[axis] = hi.position_endstop + rail.get_homed_offset()
homing_state.set_homed_position(coord)
def home(self, homing_state):
# Each axis is homed independently and in order
for axis in homing_state.get_axes():
if axis == self.dual_carriage_axis:
dc1, dc2 = self.dual_carriage_rails
altc = self.rails[axis] == dc2
self._activate_carriage(0)
self._home_axis(homing_state, axis, dc1)
self._activate_carriage(1)
self._home_axis(homing_state, axis, dc2)
self._activate_carriage(altc)
else:
self._home_axis(homing_state, axis, self.rails[axis])
def motor_off(self, print_time):
self.limits = [(1.0, -1.0)] * 3
for rail in self.rails:
rail.motor_enable(print_time, 0)
for rail in self.dual_carriage_rails:
rail.motor_enable(print_time, 0)
self.need_motor_enable = True
def _check_motor_enable(self, print_time, move):
need_motor_enable = False
for i, rail in enumerate(self.rails):
if move.axes_d[i]:
rail.motor_enable(print_time, 1)
need_motor_enable |= not rail.is_motor_enabled()
self.need_motor_enable = need_motor_enable
def _check_endstops(self, move):
end_pos = move.end_pos
for i in (0, 1, 2):
if (move.axes_d[i]
and (end_pos[i] < self.limits[i][0]
or end_pos[i] > self.limits[i][1])):
if self.limits[i][0] > self.limits[i][1]:
raise homing.EndstopMoveError(
end_pos, "Must home axis first")
raise homing.EndstopMoveError(end_pos)
def check_move(self, move):
limits = self.limits
xpos, ypos = move.end_pos[:2]
if (xpos < limits[0][0] or xpos > limits[0][1]
or ypos < limits[1][0] or ypos > limits[1][1]):
self._check_endstops(move)
if not move.axes_d[2]:
# Normal XY move - use defaults
return
# Move with Z - update velocity and accel for slower Z axis
self._check_endstops(move)
z_ratio = move.move_d / abs(move.axes_d[2])
move.limit_speed(
self.max_z_velocity * z_ratio, self.max_z_accel * z_ratio)
def move(self, print_time, move):
if self.need_motor_enable:
self._check_motor_enable(print_time, move)
for i, rail in enumerate(self.rails):
if move.axes_d[i]:
rail.step_itersolve(move.cmove)
# Dual carriage support
def _activate_carriage(self, carriage):
toolhead = self.printer.lookup_object('toolhead')
toolhead.get_last_move_time()
dc_rail = self.dual_carriage_rails[carriage]
dc_axis = self.dual_carriage_axis
self.rails[dc_axis] = dc_rail
extruder_pos = toolhead.get_position()[3]
toolhead.set_position(self.calc_position() + [extruder_pos])
if self.limits[dc_axis][0] <= self.limits[dc_axis][1]:
self.limits[dc_axis] = dc_rail.get_range()
self.need_motor_enable = True
cmd_SET_DUAL_CARRIAGE_help = "Set which carriage is active"
def cmd_SET_DUAL_CARRIAGE(self, params):
gcode = self.printer.lookup_object('gcode')
carriage = gcode.get_int('CARRIAGE', params, minval=0, maxval=1)
self._activate_carriage(carriage)
gcode.reset_last_position()
def load_kinematics(toolhead, config):
return CartKinematics(toolhead, config)