From 57564ae5763387e59cfe178d60b547c6e3462d16 Mon Sep 17 00:00:00 2001 From: Scott Lahteine Date: Sun, 21 Aug 2016 03:10:55 -0500 Subject: [PATCH] Use last probe point to correct Z when possible --- Marlin/Marlin_main.cpp | 82 +++++++++++++++++++++++------------------- 1 file changed, 46 insertions(+), 36 deletions(-) diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp index a93c2e89b..64e9cbabb 100644 --- a/Marlin/Marlin_main.cpp +++ b/Marlin/Marlin_main.cpp @@ -3397,6 +3397,8 @@ inline void gcode_G28() { bed_leveling_in_progress = true; + float xProbe, yProbe, measured_z = 0; + #if ENABLED(AUTO_BED_LEVELING_GRID) // probe at the points of a lattice grid @@ -3434,8 +3436,8 @@ inline void gcode_G28() { bool zig = auto_bed_leveling_grid_points & 1; //always end at [RIGHT_PROBE_BED_POSITION, BACK_PROBE_BED_POSITION] for (uint8_t yCount = 0; yCount < auto_bed_leveling_grid_points; yCount++) { - float yBase = front_probe_bed_position + yGridSpacing * yCount, - yProbe = floor(yBase + (yBase < 0 ? 0 : 0.5)); + float yBase = front_probe_bed_position + yGridSpacing * yCount; + yProbe = floor(yBase + (yBase < 0 ? 0 : 0.5)); int8_t xStart, xStop, xInc; if (zig) { @@ -3452,8 +3454,8 @@ inline void gcode_G28() { zig = !zig; for (int8_t xCount = xStart; xCount != xStop; xCount += xInc) { - float xBase = left_probe_bed_position + xGridSpacing * xCount, - xProbe = floor(xBase + (xBase < 0 ? 0 : 0.5)); + float xBase = left_probe_bed_position + xGridSpacing * xCount; + xProbe = floor(xBase + (xBase < 0 ? 0 : 0.5)); #if ENABLED(DELTA) // Avoid probing outside the round or hexagonal area of a delta printer @@ -3497,12 +3499,12 @@ inline void gcode_G28() { vector_3(ABL_PROBE_PT_3_X, ABL_PROBE_PT_3_Y, 0) }; - for (uint8_t i = 0; i < 3; ++i) - points[i].z = probe_pt( - LOGICAL_X_POSITION(points[i].x), - LOGICAL_Y_POSITION(points[i].y), - stow_probe_after_each, verbose_level - ); + for (uint8_t i = 0; i < 3; ++i) { + // Retain the last probe position + xProbe = LOGICAL_X_POSITION(points[i].x); + yProbe = LOGICAL_Y_POSITION(points[i].y); + measured_z = points[i].z = probe_pt(xProbe, yProbe, stow_probe_after_each, verbose_level); + } if (!dryrun) { vector_3 planeNormal = vector_3::cross(points[0] - points[1], points[2] - points[1]).get_normal(); @@ -3635,42 +3637,50 @@ inline void gcode_G28() { // Correct the current XYZ position based on the tilted plane. // - // Get the distance from the reference point to the current position - // The current XY is in sync with the planner/steppers at this point - // but the current Z is only known to the steppers. + // 1. Get the distance from the current position to the reference point. float x_dist = RAW_CURRENT_POSITION(X_AXIS) - X_TILT_FULCRUM, y_dist = RAW_CURRENT_POSITION(Y_AXIS) - Y_TILT_FULCRUM, - z_real = RAW_Z_POSITION(stepper.get_axis_position_mm(Z_AXIS)); + z_real = RAW_CURRENT_POSITION(Z_AXIS), + z_zero = 0; #if ENABLED(DEBUG_LEVELING_FEATURE) - if (DEBUGGING(LEVELING)) { - SERIAL_ECHOPAIR("BEFORE ROTATION ... x_dist:", x_dist); - SERIAL_ECHOPAIR("y_dist:", y_dist); - SERIAL_ECHOPAIR("z_real:", z_real); - } + if (DEBUGGING(LEVELING)) DEBUG_POS("G29 uncorrected XYZ", current_position); #endif - // Apply the matrix to the distance from the reference point to XY, - // and from the homed Z to the current Z. - apply_rotation_xyz(planner.bed_level_matrix, x_dist, y_dist, z_real); + matrix_3x3 inverse = matrix_3x3::transpose(planner.bed_level_matrix); - #if ENABLED(DEBUG_LEVELING_FEATURE) - if (DEBUGGING(LEVELING)) { - SERIAL_ECHOPAIR("AFTER ROTATION ... x_dist:", x_dist); - SERIAL_ECHOPAIR("y_dist:", y_dist); - SERIAL_ECHOPAIR("z_real:", z_real); - } - #endif + // 2. Apply the inverse matrix to the distance + // from the reference point to X, Y, and zero. + apply_rotation_xyz(inverse, x_dist, y_dist, z_zero); + + // 3. Get the matrix-based corrected Z. + // (Even if not used, get it for comparison.) + float new_z = z_real + z_zero; + + // 4. Use the last measured distance to the bed, if possible + if ( NEAR(current_position[X_AXIS], xProbe - (X_PROBE_OFFSET_FROM_EXTRUDER)) + && NEAR(current_position[Y_AXIS], yProbe - (Y_PROBE_OFFSET_FROM_EXTRUDER)) + ) { + float simple_z = z_real - (measured_z - (-zprobe_zoffset)); + #if ENABLED(DEBUG_LEVELING_FEATURE) + if (DEBUGGING(LEVELING)) { + SERIAL_ECHOPAIR("Z from Probe:", simple_z); + SERIAL_ECHOPAIR(" Matrix:", new_z); + SERIAL_ECHOLNPAIR(" Discrepancy:", simple_z - new_z); + } + #endif + new_z = simple_z; + } - // Apply the rotated distance and Z to the current position - current_position[X_AXIS] = LOGICAL_X_POSITION(X_TILT_FULCRUM + x_dist); - current_position[Y_AXIS] = LOGICAL_Y_POSITION(Y_TILT_FULCRUM + y_dist); - current_position[Z_AXIS] = LOGICAL_Z_POSITION(z_real); + // 5. The rotated XY and corrected Z are now current_position + current_position[X_AXIS] = LOGICAL_X_POSITION(x_dist) + X_TILT_FULCRUM; + current_position[Y_AXIS] = LOGICAL_Y_POSITION(y_dist) + Y_TILT_FULCRUM; + current_position[Z_AXIS] = LOGICAL_Z_POSITION(new_z); SYNC_PLAN_POSITION_KINEMATIC(); #if ENABLED(DEBUG_LEVELING_FEATURE) - if (DEBUGGING(LEVELING)) DEBUG_POS("> corrected XYZ in G29", current_position); + if (DEBUGGING(LEVELING)) DEBUG_POS("G29 corrected XYZ", current_position); #endif } @@ -7962,8 +7972,8 @@ void set_current_from_steppers_for_axis(AxisEnum axis) { LOOP_XYZE(i) difference[i] = target[i] - current_position[i]; float cartesian_mm = sqrt(sq(difference[X_AXIS]) + sq(difference[Y_AXIS]) + sq(difference[Z_AXIS])); - if (cartesian_mm < 0.000001) cartesian_mm = abs(difference[E_AXIS]); - if (cartesian_mm < 0.000001) return false; + if (UNEAR_ZERO(cartesian_mm)) cartesian_mm = abs(difference[E_AXIS]); + if (UNEAR_ZERO(cartesian_mm)) return false; float _feedrate_mm_s = MMS_SCALED(feedrate_mm_s); float seconds = cartesian_mm / _feedrate_mm_s; int steps = max(1, int(delta_segments_per_second * seconds));