klipper/klippy/kinematics/corexy.py

140 lines
6.2 KiB
Python
Raw Normal View History

# Code for handling the kinematics of corexy robots
#
# 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, math
import stepper, homing
class CoreXYKinematics:
def __init__(self, toolhead, config):
# Setup axis rails
self.rails = [ stepper.PrinterRail(config.getsection('stepper_x')),
stepper.PrinterRail(config.getsection('stepper_y')),
stepper.LookupMultiRail(config.getsection('stepper_z')) ]
self.rails[0].add_to_endstop(self.rails[1].get_endstops()[0][0])
self.rails[1].add_to_endstop(self.rails[0].get_endstops()[0][0])
self.rails[0].setup_itersolve('corexy_stepper_alloc', '+')
self.rails[1].setup_itersolve('corexy_stepper_alloc', '-')
self.rails[2].setup_itersolve('cartesian_stepper_alloc', 'z')
# 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()
max_xy_halt_velocity = max_halt_velocity * math.sqrt(2.)
self.rails[0].set_max_jerk(max_xy_halt_velocity, max_accel)
self.rails[1].set_max_jerk(max_xy_halt_velocity, max_accel)
self.rails[2].set_max_jerk(
min(max_halt_velocity, self.max_z_velocity), self.max_z_accel)
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):
pos = [rail.get_commanded_position() for rail in self.rails]
return [0.5 * (pos[0] + pos[1]), 0.5 * (pos[0] - pos[1]), pos[2]]
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(self, homing_state):
# Each axis is homed independently and in order
for axis in homing_state.get_axes():
rail = self.rails[axis]
# 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, homing_speed)
# Home again
coord[axis] = r2pos
homing_state.home(coord, homepos, rail.get_endstops(),
second_homing_speed, second_home=True)
if axis == 2:
# Support endstop phase detection on Z axis
coord[axis] = hi.position_endstop + rail.get_homed_offset()
homing_state.set_homed_position(coord)
def motor_off(self, print_time):
self.limits = [(1.0, -1.0)] * 3
for rail in self.rails:
rail.motor_enable(print_time, 0)
self.need_motor_enable = True
def _check_motor_enable(self, print_time, move):
if move.axes_d[0] or move.axes_d[1]:
self.rails[0].motor_enable(print_time, 1)
self.rails[1].motor_enable(print_time, 1)
if move.axes_d[2]:
self.rails[2].motor_enable(print_time, 1)
need_motor_enable = False
for rail in self.rails:
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)
axes_d = move.axes_d
cmove = move.cmove
rail_x, rail_y, rail_z = self.rails
if axes_d[0] or axes_d[1]:
rail_x.step_itersolve(cmove)
rail_y.step_itersolve(cmove)
if axes_d[2]:
rail_z.step_itersolve(cmove)
def load_kinematics(toolhead, config):
return CoreXYKinematics(toolhead, config)