✨ X Twist Compensation & Calibration (#23238)

Marlin/src/feature/bedlevel/abl/x_twist.cpp

@@ -0,0 +1,59 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2021 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#include "../../../inc/MarlinConfig.h"
+
+#if ENABLED(X_AXIS_TWIST_COMPENSATION)
+
+#include "../bedlevel.h"
+
+XATC xatc;
+
+float XATC::spacing, XATC::start;
+xatc_points_t XATC::z_values;
+
+void XATC::print_points() {
+  SERIAL_ECHOLNPGM(" X-Twist Correction:");
+  LOOP_L_N(x, XATC_MAX_POINTS) {
+    SERIAL_CHAR(' ');
+    if (!isnan(z_values[x])) {
+      if (z_values[x] >= 0) SERIAL_CHAR('+');
+      SERIAL_ECHO_F(z_values[x], 3);
+    }
+    else {
+      LOOP_L_N(i, 6)
+        SERIAL_CHAR(i ? '=' : ' ');
+    }
+  }
+  SERIAL_EOL();
+}
+
+float lerp(const_float_t t, const_float_t a, const_float_t b) { return a + t * (b - a); }
+
+float XATC::compensation(const xy_pos_t &raw) {
+  float t = (raw.x - start) / spacing;
+  int i = FLOOR(t);
+  LIMIT(i, 0, XATC_MAX_POINTS - 2);
+  t -= i;
+  return lerp(t, z_values[i], z_values[i + 1]);
+}
+
+#endif // X_AXIS_TWIST_COMPENSATION

Marlin/src/feature/bedlevel/abl/x_twist.h

@@ -0,0 +1,37 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2021 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include "../../../inc/MarlinConfigPre.h"
+
+typedef float xatc_points_t[XATC_MAX_POINTS];
+
+class XATC {
+public:
+  static float spacing, start;
+  static xatc_points_t z_values;
+
+  static float compensation(const xy_pos_t &raw);
+  static void print_points();
+};
+
+extern XATC xatc;

Marlin/src/feature/bedlevel/bedlevel.h

@@ -63,6 +63,9 @@ class TemporaryBedLevelingState {
 
   #if ENABLED(AUTO_BED_LEVELING_BILINEAR)
     #include "abl/abl.h"
+    #if ENABLED(X_AXIS_TWIST_COMPENSATION)
+      #include "abl/x_twist.h"
+    #endif
   #elif ENABLED(AUTO_BED_LEVELING_UBL)
     #include "ubl/ubl.h"
   #elif ENABLED(MESH_BED_LEVELING)