refactored block buffer into separate module motion_plan pending the …

…addition of the actual look ahead planner
wnuken · Jan 14, 2011 · 49a16cb · 49a16cb
1 parent b628a4a
commit 49a16cb
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diff --git a/Makefile b/Makefile
@@ -1,6 +1,6 @@
 # Part of Grbl
 #
-# Copyright (c) 2009 Simen Svale Skogsrud
+# Copyright (c) 2009-2011 Simen Svale Skogsrud
 #
 # Grbl is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -31,7 +31,7 @@ DEVICE = atmega328p
 CLOCK = 16000000
 PROGRAMMER = -c avrisp2 -P usb
 OBJECTS = main.o motion_control.o gcode.o spindle_control.o wiring_serial.o serial_protocol.o stepper.o \
- eeprom.o config.o
+ eeprom.o config.o motion_plan.o
 # FUSES = -U hfuse:w:0xd9:m -U lfuse:w:0x24:m
 FUSES = -U hfuse:w:0xd2:m -U lfuse:w:0xff:m
 

diff --git a/accelleration.h b/accelleration.h
diff --git a/config.c b/config.c
@@ -2,7 +2,7 @@
  config.c - eeprom and compile time configuration handling 
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/config.h b/config.h
@@ -2,7 +2,7 @@
  config.h - eeprom and compile time configuration handling 
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
@@ -27,8 +27,8 @@
 
 // Settings that can only be set at compile-time:
 
-// #define BAUD_RATE 9600
-#define BAUD_RATE 115200
+#define BAUD_RATE 9600
+//#define BAUD_RATE 115200
 
 #define STEPPERS_ENABLE_DDR DDRD
 #define STEPPERS_ENABLE_PORT PORTD

diff --git a/gcode.c b/gcode.c
@@ -2,7 +2,7 @@
  gcode.c - rs274/ngc parser.
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/gcode.h b/gcode.h
@@ -2,7 +2,7 @@
  gcode.c - rs274/ngc parser.
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/main.c b/main.c
@@ -2,7 +2,7 @@
  main.c - An embedded CNC Controller with rs274/ngc (g-code) support
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
@@ -33,6 +33,7 @@
 int main(void)
 {
  beginSerial(BAUD_RATE);
+ printString("A");
  config_init();
  st_init(); // initialize the stepper subsystem
  mc_init(); // initialize motion control subsystem

diff --git a/motion_control.c b/motion_control.c
@@ -1,8 +1,8 @@
 /*
- motion_control.c - cartesian robot controller.
+ motion_control.c - high level interface for issuing motion commands
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/motion_control.h b/motion_control.h
@@ -1,8 +1,8 @@
 /*
- motion_control.h - cartesian robot controller.
+ motion_control.h - high level interface for issuing motion commands
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/motion_plan.c b/motion_plan.c
@@ -0,0 +1,69 @@
+/*
+ motion_plan.c - buffers movement commands and manages the acceleration profile plan
+ Part of Grbl
+
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
+
+ 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 <inttypes.h>
+#include <math.h> 
+
+#include "motion_plan.h"
+#include "nuts_bolts.h"
+#include "stepper.h"
+
+struct Block block_buffer[BLOCK_BUFFER_SIZE]; // A ring buffer for motion instructions
+volatile int block_buffer_head = 0; // Index of the next block to be pushed
+volatile int block_buffer_tail = 0; // Index of the block to process now
+
+inline uint32_t estimate_acceleration_distance(int32_t current_rate, int32_t target_rate, int32_t acceleration) {
+ return((target_rate*target_rate-current_rate*current_rate)/(2*acceleration));
+}
+
+inline uint32_t estimate_acceleration_ticks(int32_t start_rate, int32_t acceleration_per_tick, int32_t step_events) {
+ return(
+ round(
+ (sqrt(2*acceleration_per_tick*step_events+(start_rate*start_rate))-start_rate)/
+ acceleration_per_tick));
+}
+
+// Calculates trapezoid parameters so that the entry- and exit-speed is compensated by the provided factors.
+// In practice both factors must be in the range 0 ... 1.0
+void calculate_trapezoid_for_block(struct Block *block, double entry_factor, double exit_factor) {
+ block->initial_rate = max(round(block->nominal_rate*entry_factor),MINIMAL_STEP_RATE);
+ int32_t final_rate = max(round(block->nominal_rate*entry_factor),MINIMAL_STEP_RATE);
+ int32_t acceleration_per_second = block->rate_delta*ACCELERATION_TICKS_PER_SECOND;
+ int32_t acceleration_steps = 
+ estimate_acceleration_distance(block->initial_rate, block->nominal_rate, acceleration_per_second);
+ int32_t decelleration_steps = 
+ estimate_acceleration_distance(block->nominal_rate, final_rate, -acceleration_per_second);
+ // Check if the acceleration and decelleration periods overlap. In that case nominal_speed will
+ // never be reached but that's okay. Just truncate both periods proportionally so that they
+ // fit within the allotted step events.
+ int32_t plateau_steps = block->step_event_count-acceleration_steps-decelleration_steps;
+ if (plateau_steps < 0) {
+ int32_t half_overlap_region = fabs(plateau_steps)/2;
+ plateau_steps = 0;
+ acceleration_steps = max(acceleration_steps-half_overlap_region,0);
+ decelleration_steps = max(decelleration_steps-half_overlap_region,0);
+ }
+ block->accelerate_ticks = estimate_acceleration_ticks(block->initial_rate, block->rate_delta, acceleration_steps);
+ if (plateau_steps) {
+ block->plateau_ticks = round(1.0*plateau_steps/(block->nominal_rate*ACCELERATION_TICKS_PER_SECOND));
+ } else {
+ block->plateau_ticks = 0;
+ }
+}
diff --git a/motion_plan.h b/motion_plan.h
@@ -0,0 +1,57 @@
+/*
+ motion_plan.h - buffers movement commands and manages the acceleration profile plan
+ Part of Grbl
+
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
+
+ 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_plan_h
+#define motion_plan_h
+
+#include <inttypes.h>
+
+// Pick a suitable block-buffer size
+#ifdef __AVR_ATmega328P__
+#define BLOCK_BUFFER_SIZE 20 // Atmega 328 has one full kilobyte of extra RAM!
+#else
+#define BLOCK_BUFFER_SIZE 5
+#endif
+
+// This struct is used when buffering the setup for each linear movement
+// "nominal" values are as specified in the source g-code and may never
+// actually be reached if acceleration management is active.
+struct Block {
+ uint32_t steps_x, steps_y, steps_z; // Step count along each axis
+ uint8_t direction_bits; // The direction bit set for this block (refers to *_DIRECTION_BIT in config.h)
+ int32_t step_event_count; // The number of step events required to complete this block
+ uint32_t nominal_rate; // The nominal step rate for this block in step_events/minute
+ // Values used for acceleration management
+ double speed_x, speed_y, speed_z; // Nominal mm/minute for each axis
+ uint32_t initial_rate; // The jerk-adjusted step rate at start of block
+ int16_t rate_delta; // The steps/minute to add or subtract when changing speed (must be positive)
+ uint16_t accelerate_ticks; // The number of acceleration-ticks to accelerate 
+ uint16_t plateau_ticks; // The number of acceleration-ticks to maintain top speed
+};
+
+extern struct Block block_buffer[BLOCK_BUFFER_SIZE]; // A ring buffer for motion instructions
+extern volatile int block_buffer_head; // Index of the next block to be pushed
+extern volatile int block_buffer_tail; // Index of the block to process now
+
+// Calculates trapezoid parameters so that the entry- and exit-speed is compensated by the provided factors.
+// In practice both factors must be in the range 0 ... 1.0
+void calculate_trapezoid_for_block(struct Block *block, double entry_factor, double exit_factor);
+
+#endif
diff --git a/notes/acceleration.c b/notes/acceleration.c
@@ -2,7 +2,7 @@
  acceleration.c - support methods for acceleration-related calcul
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/nuts_bolts.h b/nuts_bolts.h
@@ -2,7 +2,7 @@
  motion_control.h - cartesian robot controller.
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/script/console b/script/console
@@ -1,4 +1,5 @@
 socat -d -d READLINE /dev/tty.usbserial-A700e0GO,clocal=1,nonblock=1,cread=1,cs8,ixon=1,ixoff=1
+socat -d -d READLINE /dev/tty.usbserial-A9007QcR,clocal=1,nonblock=1,cread=1,cs8,ixon=1,ixoff=1
 
 #socat -d -d READLINE /dev/tty.FireFly-A964-SPP-1,clocal=1,nonblock=1,cread=1,cs8,ixon=1,ixoff=1
 
diff --git a/serial_protocol.c b/serial_protocol.c
@@ -2,7 +2,7 @@
  serial_protocol.c - the serial protocol master control unit
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/serial_protocol.h b/serial_protocol.h
@@ -2,7 +2,7 @@
  serial_protocol.h - the serial protocol master control unit
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/spindle_control.c b/spindle_control.c
@@ -2,7 +2,7 @@
  spindle_control.c - spindle control methods
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by

diff --git a/spindle_control.h b/spindle_control.h
@@ -2,7 +2,7 @@
  spindle_control.h - spindle control methods
  Part of Grbl
 
- Copyright (c) 2009 Simen Svale Skogsrud
+ Copyright (c) 2009-2011 Simen Svale Skogsrud
 
  Grbl is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by