fix(api): use consistent CriticalPoints when moving to maintenance po…

…sition (#12878)

Use the MOUNT critical point for moving to X and Y position, but still calculate final Z position based on the tip of whatever's attached to the mount

api/src/opentrons/protocol_engine/commands/calibration/move_to_maintenance_position.py

@@ -83,14 +83,23 @@ async def execute(
         ot3_api = ensure_ot3_hardware(
             self._hardware_api,
         )
-        current_position = await ot3_api.gantry_position(Mount.LEFT)
-        max_height_z = ot3_api.get_instrument_max_height(Mount.LEFT)
+        current_position_mount = await ot3_api.gantry_position(
+            Mount.LEFT, critical_point=CriticalPoint.MOUNT
+        )
+        max_height_z_mount = ot3_api.get_instrument_max_height(
+            Mount.LEFT, critical_point=CriticalPoint.MOUNT
+        )
+        max_height_z_tip = ot3_api.get_instrument_max_height(Mount.LEFT)
         # avoid using motion planning waypoints because we do not need to move the z at this moment
         movement_points = [
             # move the z to the highest position
-            Point(x=current_position.x, y=current_position.y, z=max_height_z),
+            Point(
+                x=current_position_mount.x,
+                y=current_position_mount.y,
+                z=max_height_z_mount,
+            ),
             # move in x,y without going down the z
-            Point(x=_ATTACH_POINT.x, y=_ATTACH_POINT.y, z=max_height_z),
+            Point(x=_ATTACH_POINT.x, y=_ATTACH_POINT.y, z=max_height_z_mount),
         ]
 
         for movement in movement_points:
@@ -108,7 +117,7 @@ async def execute(
                 }
             )
         else:
-            max_motion_range = max_height_z - _MAX_Z_AXIS_MOTION_RANGE
+            max_motion_range = max_height_z_tip - _MAX_Z_AXIS_MOTION_RANGE
             await ot3_api.move_axes(
                 {
                     OT3Axis.Z_L: max_motion_range + _LEFT_MOUNT_Z_MARGIN,

api/tests/opentrons/protocol_engine/commands/calibration/test_move_to_maintenance_position.py

@@ -58,9 +58,17 @@ async def test_calibration_move_to_location_implementation(
         mount=MountType.LEFT, maintenancePosition=maintenance_position
     )
 
-    decoy.when(await ot3_hardware_api.gantry_position(Mount.LEFT)).then_return(
-        Point(x=1, y=2, z=3)
-    )
+    decoy.when(
+        await ot3_hardware_api.gantry_position(
+            Mount.LEFT, critical_point=CriticalPoint.MOUNT
+        )
+    ).then_return(Point(x=1, y=2, z=3))
+
+    decoy.when(
+        ot3_hardware_api.get_instrument_max_height(
+            Mount.LEFT, critical_point=CriticalPoint.MOUNT
+        )
+    ).then_return(250)
 
     decoy.when(ot3_hardware_api.get_instrument_max_height(Mount.LEFT)).then_return(300)
 
@@ -70,7 +78,7 @@ async def test_calibration_move_to_location_implementation(
     decoy.verify(
         await ot3_hardware_api.move_to(
             mount=Mount.LEFT,
-            abs_position=Point(x=1, y=2, z=300),
+            abs_position=Point(x=1, y=2, z=250),
             critical_point=CriticalPoint.MOUNT,
         ),
         times=1,
@@ -79,7 +87,7 @@ async def test_calibration_move_to_location_implementation(
     decoy.verify(
         await ot3_hardware_api.move_to(
             mount=Mount.LEFT,
-            abs_position=Point(x=0, y=110, z=300),
+            abs_position=Point(x=0, y=110, z=250),
             critical_point=CriticalPoint.MOUNT,
         ),
         times=1,