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Merge pull request #2072 from thinkyhead/better_arc_code

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Consolidate arc code, remove motion_control.*
This commit is contained in:
Scott Lahteine 2015-05-14 00:27:22 -07:00
commit 7b3acfbb6f
5 changed files with 172 additions and 229 deletions
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4
Marlin/Makefile
View File

@ -266,8 +266,8 @@ VPATH += $(ARDUINO_INSTALL_DIR)/hardware/teensy/cores/teensy
endif endif
CXXSRC = WMath.cpp WString.cpp Print.cpp Marlin_main.cpp \ CXXSRC = WMath.cpp WString.cpp Print.cpp Marlin_main.cpp \
MarlinSerial.cpp Sd2Card.cpp SdBaseFile.cpp SdFatUtil.cpp \ MarlinSerial.cpp Sd2Card.cpp SdBaseFile.cpp SdFatUtil.cpp \
SdFile.cpp SdVolume.cpp motion_control.cpp planner.cpp \ SdFile.cpp SdVolume.cpp planner.cpp stepper.cpp \
stepper.cpp temperature.cpp cardreader.cpp configuration_store.cpp \ temperature.cpp cardreader.cpp configuration_store.cpp \
watchdog.cpp SPI.cpp servo.cpp Tone.cpp ultralcd.cpp digipot_mcp4451.cpp \ watchdog.cpp SPI.cpp servo.cpp Tone.cpp ultralcd.cpp digipot_mcp4451.cpp \
vector_3.cpp qr_solve.cpp vector_3.cpp qr_solve.cpp
ifeq ($(LIQUID_TWI2), 0) ifeq ($(LIQUID_TWI2), 0)

1
Marlin/Marlin.h
View File

@ -207,7 +207,6 @@ void disable_all_steppers();
void FlushSerialRequestResend(); void FlushSerialRequestResend();
void ok_to_send(); void ok_to_send();
void get_coordinates();
#ifdef DELTA #ifdef DELTA
void calculate_delta(float cartesian[3]); void calculate_delta(float cartesian[3]);
#ifdef ENABLE_AUTO_BED_LEVELING #ifdef ENABLE_AUTO_BED_LEVELING

219
Marlin/Marlin_main.cpp
View File

@ -47,7 +47,6 @@
#include "planner.h" #include "planner.h"
#include "stepper.h" #include "stepper.h"
#include "temperature.h" #include "temperature.h"
#include "motion_control.h"
#include "cardreader.h" #include "cardreader.h"
#include "watchdog.h" #include "watchdog.h"
#include "configuration_store.h" #include "configuration_store.h"
@ -226,7 +225,7 @@ bool Running = true;
uint8_t marlin_debug_flags = DEBUG_INFO|DEBUG_ERRORS; uint8_t marlin_debug_flags = DEBUG_INFO|DEBUG_ERRORS;
static float feedrate = 1500.0, next_feedrate, saved_feedrate; static float feedrate = 1500.0, saved_feedrate;
float current_position[NUM_AXIS] = { 0.0 }; float current_position[NUM_AXIS] = { 0.0 };
static float destination[NUM_AXIS] = { 0.0 }; static float destination[NUM_AXIS] = { 0.0 };
bool axis_known_position[3] = { false }; bool axis_known_position[3] = { false };
@ -258,7 +257,6 @@ const char errormagic[] PROGMEM = "Error:";
const char echomagic[] PROGMEM = "echo:"; const char echomagic[] PROGMEM = "echo:";
const char axis_codes[NUM_AXIS] = {'X', 'Y', 'Z', 'E'}; const char axis_codes[NUM_AXIS] = {'X', 'Y', 'Z', 'E'};
static float offset[3] = { 0 };
static bool relative_mode = false; //Determines Absolute or Relative Coordinates static bool relative_mode = false; //Determines Absolute or Relative Coordinates
static char serial_char; static char serial_char;
static int serial_count = 0; static int serial_count = 0;
@ -401,7 +399,6 @@ bool target_direction;
//================================ Functions ================================ //================================ Functions ================================
//=========================================================================== //===========================================================================
void get_arc_coordinates();
bool setTargetedHotend(int code); bool setTargetedHotend(int code);
void serial_echopair_P(const char *s_P, float v) { serialprintPGM(s_P); SERIAL_ECHO(v); } void serial_echopair_P(const char *s_P, float v) { serialprintPGM(s_P); SERIAL_ECHO(v); }
@ -1770,12 +1767,32 @@ static void homeaxis(AxisEnum axis) {
* *
*/ */
/**
* Set XYZE destination and feedrate from the current GCode command
*
* - Set destination from included axis codes
* - Set to current for missing axis codes
* - Set the feedrate, if included
*/
void gcode_get_destination() {
for (int i = 0; i < NUM_AXIS; i++) {
if (code_seen(axis_codes[i]))
destination[i] = code_value() + (axis_relative_modes[i] || relative_mode ? current_position[i] : 0);
else
destination[i] = current_position[i];
}
if (code_seen('F')) {
float next_feedrate = code_value();
if (next_feedrate > 0.0) feedrate = next_feedrate;
}
}
/** /**
* G0, G1: Coordinated movement of X Y Z E axes * G0, G1: Coordinated movement of X Y Z E axes
*/ */
inline void gcode_G0_G1() { inline void gcode_G0_G1() {
if (IsRunning()) { if (IsRunning()) {
get_coordinates(); // For X Y Z E F gcode_get_destination(); // For X Y Z E F
#ifdef FWRETRACT #ifdef FWRETRACT
@ -1797,14 +1814,158 @@ inline void gcode_G0_G1() {
} }
} }
/**
* Plan an arc in 2 dimensions
*
* The arc is approximated by generating many small linear segments.
* The length of each segment is configured in MM_PER_ARC_SEGMENT (Default 1mm)
* Arcs should only be made relatively large (over 5mm), as larger arcs with
* larger segments will tend to be more efficient. Your slicer should have
* options for G2/G3 arc generation. In future these options may be GCode tunable.
*/
void plan_arc(
float *target, // Destination position
float *offset, // Center of rotation relative to current_position
uint8_t clockwise // Clockwise?
) {
float radius = hypot(offset[X_AXIS], offset[Y_AXIS]),
center_axis0 = current_position[X_AXIS] + offset[X_AXIS],
center_axis1 = current_position[Y_AXIS] + offset[Y_AXIS],
linear_travel = target[Z_AXIS] - current_position[Z_AXIS],
extruder_travel = target[E_AXIS] - current_position[E_AXIS],
r_axis0 = -offset[X_AXIS], // Radius vector from center to current location
r_axis1 = -offset[Y_AXIS],
rt_axis0 = target[X_AXIS] - center_axis0,
rt_axis1 = target[Y_AXIS] - center_axis1;
// CCW angle of rotation between position and target from the circle center. Only one atan2() trig computation required.
float angular_travel = atan2(r_axis0*rt_axis1-r_axis1*rt_axis0, r_axis0*rt_axis0+r_axis1*rt_axis1);
if (angular_travel < 0) { angular_travel += RADIANS(360); }
if (clockwise) { angular_travel -= RADIANS(360); }
// Make a circle if the angular rotation is 0
if (current_position[X_AXIS] == target[X_AXIS] && current_position[Y_AXIS] == target[Y_AXIS] && angular_travel == 0)
angular_travel += RADIANS(360);
float mm_of_travel = hypot(angular_travel*radius, fabs(linear_travel));
if (mm_of_travel < 0.001) { return; }
uint16_t segments = floor(mm_of_travel / MM_PER_ARC_SEGMENT);
if (segments == 0) segments = 1;
float theta_per_segment = angular_travel/segments;
float linear_per_segment = linear_travel/segments;
float extruder_per_segment = extruder_travel/segments;
/* Vector rotation by transformation matrix: r is the original vector, r_T is the rotated vector,
and phi is the angle of rotation. Based on the solution approach by Jens Geisler.
r_T = [cos(phi) -sin(phi);
sin(phi) cos(phi] * r ;
For arc generation, the center of the circle is the axis of rotation and the radius vector is
defined from the circle center to the initial position. Each line segment is formed by successive
vector rotations. This requires only two cos() and sin() computations to form the rotation
matrix for the duration of the entire arc. Error may accumulate from numerical round-off, since
all double numbers are single precision on the Arduino. (True double precision will not have
round off issues for CNC applications.) Single precision error can accumulate to be greater than
tool precision in some cases. Therefore, arc path correction is implemented.
Small angle approximation may be used to reduce computation overhead further. This approximation
holds for everything, but very small circles and large MM_PER_ARC_SEGMENT values. In other words,
theta_per_segment would need to be greater than 0.1 rad and N_ARC_CORRECTION would need to be large
to cause an appreciable drift error. N_ARC_CORRECTION~=25 is more than small enough to correct for
numerical drift error. N_ARC_CORRECTION may be on the order a hundred(s) before error becomes an
issue for CNC machines with the single precision Arduino calculations.
This approximation also allows plan_arc to immediately insert a line segment into the planner
without the initial overhead of computing cos() or sin(). By the time the arc needs to be applied
a correction, the planner should have caught up to the lag caused by the initial plan_arc overhead.
This is important when there are successive arc motions.
*/
// Vector rotation matrix values
float cos_T = 1-0.5*theta_per_segment*theta_per_segment; // Small angle approximation
float sin_T = theta_per_segment;
float arc_target[4];
float sin_Ti;
float cos_Ti;
float r_axisi;
uint16_t i;
int8_t count = 0;
// Initialize the linear axis
arc_target[Z_AXIS] = current_position[Z_AXIS];
// Initialize the extruder axis
arc_target[E_AXIS] = current_position[E_AXIS];
float feed_rate = feedrate*feedrate_multiplier/60/100.0;
for (i = 1; i < segments; i++) { // Increment (segments-1)
if (count < N_ARC_CORRECTION) {
// Apply vector rotation matrix to previous r_axis0 / 1
r_axisi = r_axis0*sin_T + r_axis1*cos_T;
r_axis0 = r_axis0*cos_T - r_axis1*sin_T;
r_axis1 = r_axisi;
count++;
}
else {
// Arc correction to radius vector. Computed only every N_ARC_CORRECTION increments.
// Compute exact location by applying transformation matrix from initial radius vector(=-offset).
cos_Ti = cos(i*theta_per_segment);
sin_Ti = sin(i*theta_per_segment);
r_axis0 = -offset[X_AXIS]*cos_Ti + offset[Y_AXIS]*sin_Ti;
r_axis1 = -offset[X_AXIS]*sin_Ti - offset[Y_AXIS]*cos_Ti;
count = 0;
}
// Update arc_target location
arc_target[X_AXIS] = center_axis0 + r_axis0;
arc_target[Y_AXIS] = center_axis1 + r_axis1;
arc_target[Z_AXIS] += linear_per_segment;
arc_target[E_AXIS] += extruder_per_segment;
clamp_to_software_endstops(arc_target);
plan_buffer_line(arc_target[X_AXIS], arc_target[Y_AXIS], arc_target[Z_AXIS], arc_target[E_AXIS], feed_rate, active_extruder);
}
// Ensure last segment arrives at target location.
plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], feed_rate, active_extruder);
// As far as the parser is concerned, the position is now == target. In reality the
// motion control system might still be processing the action and the real tool position
// in any intermediate location.
set_current_to_destination();
}
/** /**
* G2: Clockwise Arc * G2: Clockwise Arc
* G3: Counterclockwise Arc * G3: Counterclockwise Arc
*/ */
inline void gcode_G2_G3(bool clockwise) { inline void gcode_G2_G3(bool clockwise) {
if (IsRunning()) { if (IsRunning()) {
get_arc_coordinates();
prepare_arc_move(clockwise); #ifdef SF_ARC_FIX
bool relative_mode_backup = relative_mode;
relative_mode = true;
#endif
gcode_get_destination();
#ifdef SF_ARC_FIX
relative_mode = relative_mode_backup;
#endif
// Center of arc as offset from current_position
float arc_offset[2] = {
code_seen('I') ? code_value() : 0,
code_seen('J') ? code_value() : 0
};
// Send an arc to the planner
plan_arc(destination, arc_offset, clockwise);
refresh_cmd_timeout();
} }
} }
@ -4308,7 +4469,7 @@ inline void gcode_M303() {
//SoftEndsEnabled = false; // Ignore soft endstops during calibration //SoftEndsEnabled = false; // Ignore soft endstops during calibration
//SERIAL_ECHOLN(" Soft endstops disabled "); //SERIAL_ECHOLN(" Soft endstops disabled ");
if (IsRunning()) { if (IsRunning()) {
//get_coordinates(); // For X Y Z E F //gcode_get_destination(); // For X Y Z E F
delta[X_AXIS] = delta_x; delta[X_AXIS] = delta_x;
delta[Y_AXIS] = delta_y; delta[Y_AXIS] = delta_y;
calculate_SCARA_forward_Transform(delta); calculate_SCARA_forward_Transform(delta);
@ -4932,7 +5093,7 @@ inline void gcode_T() {
make_move = true; make_move = true;
#endif #endif
next_feedrate = code_value(); float next_feedrate = code_value();
if (next_feedrate > 0.0) feedrate = next_feedrate; if (next_feedrate > 0.0) feedrate = next_feedrate;
} }
#if EXTRUDERS > 1 #if EXTRUDERS > 1
@ -5562,33 +5723,6 @@ void ok_to_send() {
SERIAL_EOL; SERIAL_EOL;
} }
void get_coordinates() {
for (int i = 0; i < NUM_AXIS; i++) {
if (code_seen(axis_codes[i]))
destination[i] = code_value() + (axis_relative_modes[i] || relative_mode ? current_position[i] : 0);
else
destination[i] = current_position[i];
}
if (code_seen('F')) {
next_feedrate = code_value();
if (next_feedrate > 0.0) feedrate = next_feedrate;
}
}
void get_arc_coordinates() {
#ifdef SF_ARC_FIX
bool relative_mode_backup = relative_mode;
relative_mode = true;
#endif
get_coordinates();
#ifdef SF_ARC_FIX
relative_mode = relative_mode_backup;
#endif
offset[0] = code_seen('I') ? code_value() : 0;
offset[1] = code_seen('J') ? code_value() : 0;
}
void clamp_to_software_endstops(float target[3]) { void clamp_to_software_endstops(float target[3]) {
if (min_software_endstops) { if (min_software_endstops) {
NOLESS(target[X_AXIS], min_pos[X_AXIS]); NOLESS(target[X_AXIS], min_pos[X_AXIS]);
@ -5912,19 +6046,6 @@ void prepare_move() {
set_current_to_destination(); set_current_to_destination();
} }
void prepare_arc_move(char isclockwise) {
float r = hypot(offset[X_AXIS], offset[Y_AXIS]); // Compute arc radius for mc_arc
// Trace the arc
mc_arc(current_position, destination, offset, X_AXIS, Y_AXIS, Z_AXIS, feedrate*feedrate_multiplier/60/100.0, r, isclockwise, active_extruder);
// As far as the parser is concerned, the position is now == target. In reality the
// motion control system might still be processing the action and the real tool position
// in any intermediate location.
set_current_to_destination();
refresh_cmd_timeout();
}
#if HAS_CONTROLLERFAN #if HAS_CONTROLLERFAN
void controllerFan() { void controllerFan() {

145
Marlin/motion_control.cpp
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@ -1,145 +0,0 @@
/*
motion_control.c - high level interface for issuing motion commands
Part of Grbl
Copyright (c) 2009-2011 Simen Svale Skogsrud
Copyright (c) 2011 Sungeun K. Jeon
Grbl 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.
Grbl 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 Grbl. If not, see <http://www.gnu.org/licenses/>.
*/
#include "Marlin.h"
#include "stepper.h"
#include "planner.h"
// The arc is approximated by generating a huge number of tiny, linear segments. The length of each
// segment is configured in settings.mm_per_arc_segment.
void mc_arc(float *position, float *target, float *offset, uint8_t axis_0, uint8_t axis_1,
uint8_t axis_linear, float feed_rate, float radius, uint8_t isclockwise, uint8_t extruder)
{
// int acceleration_manager_was_enabled = plan_is_acceleration_manager_enabled();
// plan_set_acceleration_manager_enabled(false); // disable acceleration management for the duration of the arc
float center_axis0 = position[axis_0] + offset[axis_0];
float center_axis1 = position[axis_1] + offset[axis_1];
float linear_travel = target[axis_linear] - position[axis_linear];
float extruder_travel = target[E_AXIS] - position[E_AXIS];
float r_axis0 = -offset[axis_0]; // Radius vector from center to current location
float r_axis1 = -offset[axis_1];
float rt_axis0 = target[axis_0] - center_axis0;
float rt_axis1 = target[axis_1] - center_axis1;
// CCW angle between position and target from circle center. Only one atan2() trig computation required.
float angular_travel = atan2(r_axis0*rt_axis1-r_axis1*rt_axis0, r_axis0*rt_axis0+r_axis1*rt_axis1);
if (angular_travel < 0) { angular_travel += 2*M_PI; }
if (isclockwise) { angular_travel -= 2*M_PI; }
//20141002:full circle for G03 did not work, e.g. G03 X80 Y80 I20 J0 F2000 is giving an Angle of zero so head is not moving
//to compensate when start pos = target pos && angle is zero -> angle = 2Pi
if (position[axis_0] == target[axis_0] && position[axis_1] == target[axis_1] && angular_travel == 0)
{
angular_travel += 2*M_PI;
}
//end fix G03
float millimeters_of_travel = hypot(angular_travel*radius, fabs(linear_travel));
if (millimeters_of_travel < 0.001) { return; }
uint16_t segments = floor(millimeters_of_travel/MM_PER_ARC_SEGMENT);
if(segments == 0) segments = 1;
/*
// Multiply inverse feed_rate to compensate for the fact that this movement is approximated
// by a number of discrete segments. The inverse feed_rate should be correct for the sum of
// all segments.
if (invert_feed_rate) { feed_rate *= segments; }
*/
float theta_per_segment = angular_travel/segments;
float linear_per_segment = linear_travel/segments;
float extruder_per_segment = extruder_travel/segments;
/* Vector rotation by transformation matrix: r is the original vector, r_T is the rotated vector,
and phi is the angle of rotation. Based on the solution approach by Jens Geisler.
r_T = [cos(phi) -sin(phi);
sin(phi) cos(phi] * r ;
For arc generation, the center of the circle is the axis of rotation and the radius vector is
defined from the circle center to the initial position. Each line segment is formed by successive
vector rotations. This requires only two cos() and sin() computations to form the rotation
matrix for the duration of the entire arc. Error may accumulate from numerical round-off, since
all double numbers are single precision on the Arduino. (True double precision will not have
round off issues for CNC applications.) Single precision error can accumulate to be greater than
tool precision in some cases. Therefore, arc path correction is implemented.
Small angle approximation may be used to reduce computation overhead further. This approximation
holds for everything, but very small circles and large mm_per_arc_segment values. In other words,
theta_per_segment would need to be greater than 0.1 rad and N_ARC_CORRECTION would need to be large
to cause an appreciable drift error. N_ARC_CORRECTION~=25 is more than small enough to correct for
numerical drift error. N_ARC_CORRECTION may be on the order a hundred(s) before error becomes an
issue for CNC machines with the single precision Arduino calculations.
This approximation also allows mc_arc to immediately insert a line segment into the planner
without the initial overhead of computing cos() or sin(). By the time the arc needs to be applied
a correction, the planner should have caught up to the lag caused by the initial mc_arc overhead.
This is important when there are successive arc motions.
*/
// Vector rotation matrix values
float cos_T = 1-0.5*theta_per_segment*theta_per_segment; // Small angle approximation
float sin_T = theta_per_segment;
float arc_target[4];
float sin_Ti;
float cos_Ti;
float r_axisi;
uint16_t i;
int8_t count = 0;
// Initialize the linear axis
arc_target[axis_linear] = position[axis_linear];
// Initialize the extruder axis
arc_target[E_AXIS] = position[E_AXIS];
for (i = 1; i<segments; i++) { // Increment (segments-1)
if (count < N_ARC_CORRECTION) {
// Apply vector rotation matrix
r_axisi = r_axis0*sin_T + r_axis1*cos_T;
r_axis0 = r_axis0*cos_T - r_axis1*sin_T;
r_axis1 = r_axisi;
count++;
} else {
// Arc correction to radius vector. Computed only every N_ARC_CORRECTION increments.
// Compute exact location by applying transformation matrix from initial radius vector(=-offset).
cos_Ti = cos(i*theta_per_segment);
sin_Ti = sin(i*theta_per_segment);
r_axis0 = -offset[axis_0]*cos_Ti + offset[axis_1]*sin_Ti;
r_axis1 = -offset[axis_0]*sin_Ti - offset[axis_1]*cos_Ti;
count = 0;
}
// Update arc_target location
arc_target[axis_0] = center_axis0 + r_axis0;
arc_target[axis_1] = center_axis1 + r_axis1;
arc_target[axis_linear] += linear_per_segment;
arc_target[E_AXIS] += extruder_per_segment;
clamp_to_software_endstops(arc_target);
plan_buffer_line(arc_target[X_AXIS], arc_target[Y_AXIS], arc_target[Z_AXIS], arc_target[E_AXIS], feed_rate, extruder);
}
// Ensure last segment arrives at target location.
plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], feed_rate, extruder);
// plan_set_acceleration_manager_enabled(acceleration_manager_was_enabled);
}

32
Marlin/motion_control.h
View File

@ -1,32 +0,0 @@
/*
motion_control.h - high level interface for issuing motion commands
Part of Grbl
Copyright (c) 2009-2011 Simen Svale Skogsrud
Copyright (c) 2011 Sungeun K. Jeon
Grbl 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.
Grbl 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 Grbl. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef motion_control_h
#define motion_control_h
// Execute an arc in offset mode format. position == current xyz, target == target xyz,
// offset == offset from current xyz, axis_XXX defines circle plane in tool space, axis_linear is
// the direction of helical travel, radius == circle radius, isclockwise boolean. Used
// for vector transformation direction.
void mc_arc(float *position, float *target, float *offset, unsigned char axis_0, unsigned char axis_1,
unsigned char axis_linear, float feed_rate, float radius, unsigned char isclockwise, uint8_t extruder);
#endif