Z_PROBE_REPEATABILITY test

Z_PROBE_REPEATABILITY test for Auto Bed Leveling.
Implemented as M48 with extra user specified options.
Full support at
http://3dprintboard.com/showthread.php?2802-Auto_Bed_Leveling-Z-Probe-Repeatability-code

Marlin/Configuration.h

@@ -375,7 +375,8 @@ const bool Z_MAX_ENDSTOP_INVERTING = true; // set to true to invert the logic of
 #define Z_MAX_LENGTH (Z_MAX_POS - Z_MIN_POS)
 //============================= Bed Auto Leveling ===========================
 
-//#define ENABLE_AUTO_BED_LEVELING // Delete the comment to enable (remove // at the start of the line)
+#define ENABLE_AUTO_BED_LEVELING // Delete the comment to enable (remove // at the start of the line)
+#define Z_PROBE_REPEATABILITY_TEST  // Delete the comment to enable (remove // at the start of the line)
 
 #ifdef ENABLE_AUTO_BED_LEVELING
 

Marlin/Marlin_main.cpp

@@ -894,7 +894,7 @@ static void set_bed_level_equation_lsq(double *plane_equation_coefficients)
     current_position[Y_AXIS] = corrected_position.y;
     current_position[Z_AXIS] = corrected_position.z;
 
-    // but the bed at 0 so we don't go below it.
+    // put the bed at 0 so we don't go below it.
     current_position[Z_AXIS] = zprobe_zoffset; // in the lsq we reach here after raising the extruder due to the loop structure
 
     plan_set_position(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS]);
@@ -1862,6 +1862,280 @@ void process_commands()
         }
       }
      break;
+
+// M48 Z-Probe repeatability measurement function.
+//
+// Usage:   M48 <n #_samples> <X X_position_for_samples> <Y Y_position_for_samples> <V Verbose_Level> <Engage_probe_for_each_reading> <L legs_of_movement_prior_to_doing_probe>
+//	
+// This function assumes the bed has been homed.  Specificaly, that a G28 command
+// as been issued prior to invoking the M48 Z-Probe repeatability measurement function.
+// Any information generated by a prior G29 Bed leveling command will be lost and need to be
+// regenerated.
+//
+// The number of samples will default to 10 if not specified.  You can use upper or lower case
+// letters for any of the options EXCEPT n.  n must be in lower case because Marlin uses a capital
+// N for its communication protocol and will get horribly confused if you send it a capital N.
+//
+
+#ifdef ENABLE_AUTO_BED_LEVELING
+#ifdef Z_PROBE_REPEATABILITY_TEST 
+
+    case 48: // M48 Z-Probe repeatability
+        {
+            #if Z_MIN_PIN == -1
+            #error "You must have a Z_MIN endstop in order to enable calculation of Z-Probe repeatability."
+            #endif
+
+	double sum=0.0; 
+	double mean=0.0; 
+	double sigma=0.0;
+	double sample_set[50];
+	int verbose_level=1, n=0, j, n_samples = 10, n_legs=0, engage_probe_for_each_reading=0 ;
+	double X_current, Y_current, Z_current;
+	double X_probe_location, Y_probe_location, Z_start_location, ext_position;
+	
+	if (code_seen('V') || code_seen('v')) {
+        	verbose_level = code_value();
+		if (verbose_level<0 || verbose_level>4 ) {
+			SERIAL_PROTOCOLPGM("?Verbose Level not plausable.\n");
+			goto Sigma_Exit;
+		}
+	}
+
+	if (verbose_level > 0)   {
+		SERIAL_PROTOCOLPGM("M48 Z-Probe Repeatability test.   Version 2.00\n");
+		SERIAL_PROTOCOLPGM("Full support at: http://3dprintboard.com/forum.php\n");
+	}
+
+	if (code_seen('n')) {
+        	n_samples = code_value();
+		if (n_samples<4 || n_samples>50 ) {
+			SERIAL_PROTOCOLPGM("?Specified sample size not plausable.\n");
+			goto Sigma_Exit;
+		}
+	}
+
+	X_current = X_probe_location = st_get_position_mm(X_AXIS);
+	Y_current = Y_probe_location = st_get_position_mm(Y_AXIS);
+	Z_current = st_get_position_mm(Z_AXIS);
+	Z_start_location = st_get_position_mm(Z_AXIS) + Z_RAISE_BEFORE_PROBING;
+	ext_position	 = st_get_position_mm(E_AXIS);
+
+	if (code_seen('E') || code_seen('e') ) 
+		engage_probe_for_each_reading++;
+
+	if (code_seen('X') || code_seen('x') ) {
+        	X_probe_location = code_value() -  X_PROBE_OFFSET_FROM_EXTRUDER;
+		if (X_probe_location<X_MIN_POS || X_probe_location>X_MAX_POS ) {
+			SERIAL_PROTOCOLPGM("?Specified X position out of range.\n");
+			goto Sigma_Exit;
+		}
+	}
+
+	if (code_seen('Y') || code_seen('y') ) {
+        	Y_probe_location = code_value() -  Y_PROBE_OFFSET_FROM_EXTRUDER;
+		if (Y_probe_location<Y_MIN_POS || Y_probe_location>Y_MAX_POS ) {
+			SERIAL_PROTOCOLPGM("?Specified Y position out of range.\n");
+			goto Sigma_Exit;
+		}
+	}
+
+	if (code_seen('L') || code_seen('l') ) {
+        	n_legs = code_value();
+		if ( n_legs==1 ) 
+			n_legs = 2;
+		if ( n_legs<0 || n_legs>15 ) {
+			SERIAL_PROTOCOLPGM("?Specified number of legs in movement not plausable.\n");
+			goto Sigma_Exit;
+		}
+	}
+
+//
+// Do all the preliminary setup work.   First raise the probe.
+//
+
+        st_synchronize();
+        plan_bed_level_matrix.set_to_identity();
+	plan_buffer_line( X_current, Y_current, Z_start_location,
+			ext_position,
+    			homing_feedrate[Z_AXIS]/60,
+			active_extruder);
+        st_synchronize();
+
+//
+// Now get everything to the specified probe point So we can safely do a probe to
+// get us close to the bed.  If the Z-Axis is far from the bed, we don't want to 
+// use that as a starting point for each probe.
+//
+	if (verbose_level > 2) 
+		SERIAL_PROTOCOL("Positioning probe for the test.\n");
+
+	plan_buffer_line( X_probe_location, Y_probe_location, Z_start_location,
+			ext_position,
+    			homing_feedrate[X_AXIS]/60,
+			active_extruder);
+        st_synchronize();
+
+	current_position[X_AXIS] = X_current = st_get_position_mm(X_AXIS);
+	current_position[Y_AXIS] = Y_current = st_get_position_mm(Y_AXIS);
+	current_position[Z_AXIS] = Z_current = st_get_position_mm(Z_AXIS);
+	current_position[E_AXIS] = ext_position = st_get_position_mm(E_AXIS);
+
+// 
+// OK, do the inital probe to get us close to the bed.
+// Then retrace the right amount and use that in subsequent probes
+//
+
+        engage_z_probe();	
+
+	setup_for_endstop_move();
+	run_z_probe();
+
+	current_position[Z_AXIS] = Z_current = st_get_position_mm(Z_AXIS);
+	Z_start_location = st_get_position_mm(Z_AXIS) + Z_RAISE_BEFORE_PROBING;
+
+	plan_buffer_line( X_probe_location, Y_probe_location, Z_start_location,
+			ext_position,
+    			homing_feedrate[X_AXIS]/60,
+			active_extruder);
+        st_synchronize();
+	current_position[Z_AXIS] = Z_current = st_get_position_mm(Z_AXIS);
+
+	if (engage_probe_for_each_reading)
+        	retract_z_probe();
+
+        for( n=0; n<n_samples; n++) {
+
+		do_blocking_move_to( X_probe_location, Y_probe_location, Z_start_location); // Make sure we are at the probe location
+
+		if ( n_legs)  {
+		double radius=0.0, theta=0.0, x_sweep, y_sweep;
+		int rotational_direction, l;
+
+			rotational_direction = (unsigned long) millis() & 0x0001;			// clockwise or counter clockwise
+			radius = (unsigned long) millis() % (long) (X_MAX_LENGTH/4); 			// limit how far out to go 
+			theta = (float) ((unsigned long) millis() % (long) 360) / (360./(2*3.1415926));	// turn into radians
+
+//SERIAL_ECHOPAIR("starting radius: ",radius);
+//SERIAL_ECHOPAIR("   theta: ",theta);
+//SERIAL_ECHOPAIR("   direction: ",rotational_direction);
+//SERIAL_PROTOCOLLNPGM("");
+
+			for( l=0; l<n_legs-1; l++) {
+				if (rotational_direction==1)
+					theta += (float) ((unsigned long) millis() % (long) 20) / (360.0/(2*3.1415926)); // turn into radians
+				else
+					theta -= (float) ((unsigned long) millis() % (long) 20) / (360.0/(2*3.1415926)); // turn into radians
+
+				radius += (float) ( ((long) ((unsigned long) millis() % (long) 10)) - 5);
+				if ( radius<0.0 )
+					radius = -radius;
+
+				X_current = X_probe_location + cos(theta) * radius;
+				Y_current = Y_probe_location + sin(theta) * radius;
+
+				if ( X_current<X_MIN_POS)		// Make sure our X & Y are sane
+					 X_current = X_MIN_POS;
+				if ( X_current>X_MAX_POS)
+					 X_current = X_MAX_POS;
+
+				if ( Y_current<Y_MIN_POS)		// Make sure our X & Y are sane
+					 Y_current = Y_MIN_POS;
+				if ( Y_current>Y_MAX_POS)
+					 Y_current = Y_MAX_POS;
+
+				if (verbose_level>3 ) {
+					SERIAL_ECHOPAIR("x: ", X_current);
+					SERIAL_ECHOPAIR("y: ", Y_current);
+					SERIAL_PROTOCOLLNPGM("");
+				}
+
+				do_blocking_move_to( X_current, Y_current, Z_current );
+			}
+			do_blocking_move_to( X_probe_location, Y_probe_location, Z_start_location); // Go back to the probe location
+		}
+
+		if (engage_probe_for_each_reading)  {
+        		engage_z_probe();	
+          		delay(1000);
+		}
+
+		setup_for_endstop_move();
+                run_z_probe();
+
+		sample_set[n] = current_position[Z_AXIS];
+
+//
+// Get the current mean for the data points we have so far
+//
+		sum=0.0; 
+		for( j=0; j<=n; j++) {
+			sum = sum + sample_set[j];
+		}
+		mean = sum / (double (n+1));
+//
+// Now, use that mean to calculate the standard deviation for the
+// data points we have so far
+//
+
+		sum=0.0; 
+		for( j=0; j<=n; j++) {
+			sum = sum + (sample_set[j]-mean) * (sample_set[j]-mean);
+		}
+		sigma = sqrt( sum / (double (n+1)) );
+
+		if (verbose_level > 1) {
+			SERIAL_PROTOCOL(n+1);
+			SERIAL_PROTOCOL(" of ");
+			SERIAL_PROTOCOL(n_samples);
+			SERIAL_PROTOCOLPGM("   z: ");
+			SERIAL_PROTOCOL_F(current_position[Z_AXIS], 6);
+		}
+
+		if (verbose_level > 2) {
+			SERIAL_PROTOCOL(" mean: ");
+			SERIAL_PROTOCOL_F(mean,6);
+
+			SERIAL_PROTOCOL("   sigma: ");
+			SERIAL_PROTOCOL_F(sigma,6);
+		}
+
+		if (verbose_level > 0) 
+			SERIAL_PROTOCOLPGM("\n");
+
+		plan_buffer_line( X_probe_location, Y_probe_location, Z_start_location, 
+				  current_position[E_AXIS], homing_feedrate[Z_AXIS]/60, active_extruder);
+        	st_synchronize();
+
+		if (engage_probe_for_each_reading)  {
+        		retract_z_probe();	
+          		delay(1000);
+		}
+	}
+
+        retract_z_probe();
+	delay(1000);
+
+        clean_up_after_endstop_move();
+
+//      enable_endstops(true);
+
+	if (verbose_level > 0) {
+		SERIAL_PROTOCOLPGM("Mean: ");
+		SERIAL_PROTOCOL_F(mean, 6);
+		SERIAL_PROTOCOLPGM("\n");
+	}
+
+SERIAL_PROTOCOLPGM("Standard Deviation: ");
+SERIAL_PROTOCOL_F(sigma, 6);
+SERIAL_PROTOCOLPGM("\n\n");
+
+Sigma_Exit:
+        break;
+	}
+#endif		// Z_PROBE_REPEATABILITY_TEST 
+#endif		// ENABLE_AUTO_BED_LEVELING
+
     case 104: // M104
       if(setTargetedHotend(104)){
         break;