Touch-MI probe by hotends.fr (#14101)

A simple Z probe using a magnet to deploy a probe. See https://youtu.be/E7Ik9PbKPl0 for the sensor description...

Marlin/Configuration.h

@@ -829,6 +829,22 @@
  */
 //#define BLTOUCH
 
+/**
+ * Touch-MI Probe by hotends.fr
+ *
+ * This probe is deployed and activated by moving the X-axis to a magnet at the edge of the bed.
+ * By default, the magnet is assumed to be on the left and activated by a home. If the magnet is
+ * on the right, enable and set TOUCH_MI_DEPLOY_XPOS to the deploy position.
+ *
+ * Also requires: BABYSTEPPING, BABYSTEP_ZPROBE_OFFSET, Z_SAFE_HOMING,
+ *                MIN_PROBE_EDGE, and a minimum Z_HOMING_HEIGHT of 10.
+ */
+//#define TOUCH_MI_PROBE
+#if ENABLED(TOUCH_MI_PROBE)
+  #define TOUCH_MI_RETRACT_Z 0.5                  // Height at which the probe retracts
+  //#define TOUCH_MI_DEPLOY_XPOS (X_MAX_BED + 2)  // For a magnet on the right side of the bed
+#endif
+
 // A probe that is deployed and stowed with a solenoid pin (SOL1_PIN)
 //#define SOLENOID_PROBE
 

Marlin/src/core/utility.cpp

@@ -66,6 +66,8 @@ void safe_delay(millis_t ms) {
         "BLTOUCH"
       #elif HAS_Z_SERVO_PROBE
         "SERVO PROBE"
+      #elif ENABLED(TOUCH_MI_PROBE)
+        "TOUCH_MI_PROBE"
       #elif ENABLED(Z_PROBE_SLED)
         "Z_PROBE_SLED"
       #elif ENABLED(Z_PROBE_ALLEN_KEY)

Marlin/src/inc/Conditionals_LCD.h

@@ -502,7 +502,7 @@
 /**
  * Set flags for enabled probes
  */
-#define HAS_BED_PROBE (HAS_Z_SERVO_PROBE || ANY(FIX_MOUNTED_PROBE, Z_PROBE_ALLEN_KEY, Z_PROBE_SLED, SOLENOID_PROBE, SENSORLESS_PROBING, RACK_AND_PINION_PROBE))
+#define HAS_BED_PROBE (HAS_Z_SERVO_PROBE || ANY(FIX_MOUNTED_PROBE, TOUCH_MI_PROBE, Z_PROBE_ALLEN_KEY, Z_PROBE_SLED, SOLENOID_PROBE, SENSORLESS_PROBING, RACK_AND_PINION_PROBE))
 #define PROBE_SELECTED (HAS_BED_PROBE || EITHER(PROBE_MANUALLY, MESH_BED_LEVELING))
 
 #if HAS_BED_PROBE

Marlin/src/inc/SanityCheck.h

@@ -985,11 +985,12 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
   + ENABLED(FIX_MOUNTED_PROBE) \
   + (HAS_Z_SERVO_PROBE && DISABLED(BLTOUCH)) \
   + ENABLED(BLTOUCH) \
+  + ENABLED(TOUCH_MI_PROBE) \
   + ENABLED(SOLENOID_PROBE) \
   + ENABLED(Z_PROBE_ALLEN_KEY) \
   + ENABLED(Z_PROBE_SLED) \
   + ENABLED(RACK_AND_PINION_PROBE)
-  #error "Please enable only one probe option: PROBE_MANUALLY, FIX_MOUNTED_PROBE, BLTOUCH, SOLENOID_PROBE, Z_PROBE_ALLEN_KEY, Z_PROBE_SLED, or Z Servo."
+  #error "Please enable only one probe option: PROBE_MANUALLY, FIX_MOUNTED_PROBE, BLTOUCH, TOUCH_MI_PROBE, SOLENOID_PROBE, Z_PROBE_ALLEN_KEY, Z_PROBE_SLED, or Z Servo."
 #endif
 
 #if HAS_BED_PROBE
@@ -1046,6 +1047,25 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
     #error "RACK_AND_PINION_PROBE requires Z_PROBE_DEPLOY_X and Z_PROBE_RETRACT_X."
   #endif
 
+  /**
+   * Touch-MI probe requirements
+   */
+  #if ENABLED(TOUCH_MI_PROBE)
+    #if ENABLED(Z_SAFE_HOMING)
+      #error "TOUCH_MI_PROBE requires Z_SAFE_HOMING."
+    #elif ENABLED(TOUCH_MI_RETRACT_Z)
+      #error "TOUCH_MI_PROBE requires TOUCH_MI_RETRACT_Z."
+    #elif defined(Z_AFTER_PROBING)
+      #error "TOUCH_MI_PROBE requires Z_AFTER_PROBING to be disabled."
+    #elif Z_HOMING_HEIGHT < 10
+      #error "TOUCH_MI_PROBE requires Z_HOMING_HEIGHT >= 10."
+    #elif Z_MIN_PROBE_ENDSTOP_INVERTING
+      #error "TOUCH_MI_PROBE requires Z_MIN_PROBE_ENDSTOP_INVERTING to be set to false."
+    #elif DISABLED(BABYSTEP_ZPROBE_OFFSET)
+      #error "TOUCH_MI_PROBE requires BABYSTEPPING with BABYSTEP_ZPROBE_OFFSET."
+    #endif
+  #endif
+
   /**
    * Require pin options and pins to be defined
    */

Marlin/src/module/probe.cpp

@@ -103,6 +103,26 @@ float zprobe_zoffset; // Initialized by settings.load()
     #endif
   }
 
+#elif ENABLED(TOUCH_MI_PROBE)
+
+  // Move to the magnet to unlock the probe
+  void run_deploy_moves_script() {
+    #ifndef TOUCH_MI_DEPLOY_XPOS
+      #define TOUCH_MI_DEPLOY_XPOS 0
+    #elif X_HOME_DIR > 0 && TOUCH_MI_DEPLOY_XPOS > X_MAX_BED
+      TemporaryGlobalEndstopsState unlock_x(false);
+    #endif
+    do_blocking_move_to_x(TOUCH_MI_DEPLOY_XPOS);
+  }
+
+  // Move down to the bed to stow the probe
+  void run_stow_moves_script() {
+    const float old_pos[] = { current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS] };
+    endstops.enable_z_probe(false);
+    do_blocking_move_to_z(TOUCH_MI_RETRACT_Z, MMM_TO_MMS(HOMING_FEEDRATE_Z));
+    do_blocking_move_to(old_pos, MMM_TO_MMS(HOMING_FEEDRATE_Z));
+  }
+
 #elif ENABLED(Z_PROBE_ALLEN_KEY)
 
   void run_deploy_moves_script() {
@@ -366,7 +386,7 @@ FORCE_INLINE void probe_specific_action(const bool deploy) {
       if (deploy) bltouch.deploy(); else bltouch.stow();
     #endif
 
-  #elif ENABLED(Z_PROBE_ALLEN_KEY)
+  #elif EITHER(TOUCH_MI_PROBE, Z_PROBE_ALLEN_KEY)
 
     deploy ? run_deploy_moves_script() : run_stow_moves_script();