klipper update

klippy/extras/safe_z_home.py

@@ -0,0 +1,88 @@
+# Perform Z Homing at specific XY coordinates.
+#
+# Copyright (C) 2019 Florian Heilmann <Florian.Heilmann@gmx.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+
+class SafeZHoming:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        x_pos, y_pos = config.getfloatlist("home_xy_position", count=2)
+        self.home_x_pos, self.home_y_pos = x_pos, y_pos
+        self.z_hop = config.getfloat("z_hop", default=0.0)
+        self.z_hop_speed = config.getfloat('z_hop_speed', 15., above=0.)
+        zconfig = config.getsection('stepper_z')
+        self.max_z = zconfig.getfloat('position_max', note_valid=False)
+        self.speed = config.getfloat('speed', 50.0, above=0.)
+        self.move_to_previous = config.getboolean('move_to_previous', False)
+        self.printer.load_object(config, 'homing')
+        self.gcode = self.printer.lookup_object('gcode')
+        self.prev_G28 = self.gcode.register_command("G28", None)
+        self.gcode.register_command("G28", self.cmd_G28)
+
+        if config.has_section("homing_override"):
+            raise config.error("homing_override and safe_z_homing cannot"
+                               +" be used simultaneously")
+
+    def cmd_G28(self, gcmd):
+        toolhead = self.printer.lookup_object('toolhead')
+
+        # Perform Z Hop if necessary
+        if self.z_hop != 0.0:
+            # Check if Z axis is homed and its last known position
+            curtime = self.printer.get_reactor().monotonic()
+            kin_status = toolhead.get_kinematics().get_status(curtime)
+            pos = toolhead.get_position()
+
+            if 'z' not in kin_status['homed_axes']:
+                # Always perform the z_hop if the Z axis is not homed
+                pos[2] = 0
+                toolhead.set_position(pos, homing_axes=[2])
+                toolhead.manual_move([None, None, self.z_hop],
+                                     self.z_hop_speed)
+                if hasattr(toolhead.get_kinematics(), "note_z_not_homed"):
+                    toolhead.get_kinematics().note_z_not_homed()
+            elif pos[2] < self.z_hop:
+                # If the Z axis is homed, and below z_hop, lift it to z_hop
+                toolhead.manual_move([None, None, self.z_hop],
+                                     self.z_hop_speed)
+
+        # Determine which axes we need to home
+        need_x, need_y, need_z = [gcmd.get(axis, None) is not None
+                                  for axis in "XYZ"]
+        if not need_x and not need_y and not need_z:
+            need_x = need_y = need_z = True
+
+        # Home XY axes if necessary
+        new_params = {}
+        if need_x:
+            new_params['X'] = '0'
+        if need_y:
+            new_params['Y'] = '0'
+        if new_params:
+            g28_gcmd = self.gcode.create_gcode_command("G28", "G28", new_params)
+            self.prev_G28(g28_gcmd)
+
+        # Home Z axis if necessary
+        if need_z:
+            # Throw an error if X or Y are not homed
+            curtime = self.printer.get_reactor().monotonic()
+            kin_status = toolhead.get_kinematics().get_status(curtime)
+            if ('x' not in kin_status['homed_axes'] or
+                'y' not in kin_status['homed_axes']):
+                raise gcmd.error("Must home X and Y axes first")
+            # Move to safe XY homing position
+            prevpos = toolhead.get_position()
+            toolhead.manual_move([self.home_x_pos, self.home_y_pos], self.speed)
+            # Home Z
+            g28_gcmd = self.gcode.create_gcode_command("G28", "G28", {'Z': '0'})
+            self.prev_G28(g28_gcmd)
+            # Perform Z Hop again for pressure-based probes
+            if self.z_hop:
+                toolhead.manual_move([None, None, self.z_hop], self.z_hop_speed)
+            # Move XY back to previous positions
+            if self.move_to_previous:
+                toolhead.manual_move(prevpos[:2], self.speed)
+
+def load_config(config):
+    return SafeZHoming(config)