️ Optimize Planner calculations (#24484)

This commit is contained in:
tombrazier 2022-07-16 00:15:51 +01:00 committed by Scott Lahteine
parent 0a164a88fe
commit cc4fc28fe0
2 changed files with 78 additions and 108 deletions

View File

@ -28,12 +28,14 @@
* Derived from Grbl
* Copyright (c) 2009-2011 Simen Svale Skogsrud
*
* The ring buffer implementation gleaned from the wiring_serial library by David A. Mellis.
* Ring buffer gleaned from wiring_serial library by David A. Mellis.
*
* Fast inverse function needed for Bézier interpolation for AVR
* was designed, written and tested by Eduardo José Tagle, April 2018.
*
* Reasoning behind the mathematics in this module (in the key of 'Mathematica'):
* Planner mathematics (Mathematica-style):
*
* s == speed, a == acceleration, t == time, d == distance
* Where: s == speed, a == acceleration, t == time, d == distance
*
* Basic definitions:
* Speed[s_, a_, t_] := s + (a*t)
@ -41,7 +43,7 @@
*
* Distance to reach a specific speed with a constant acceleration:
* Solve[{Speed[s, a, t] == m, Travel[s, a, t] == d}, d, t]
* d -> (m^2 - s^2)/(2 a) --> estimate_acceleration_distance()
* d -> (m^2 - s^2) / (2 a)
*
* Speed after a given distance of travel with constant acceleration:
* Solve[{Speed[s, a, t] == m, Travel[s, a, t] == d}, m, t]
@ -49,17 +51,18 @@
*
* DestinationSpeed[s_, a_, d_] := Sqrt[2 a d + s^2]
*
* When to start braking (di) to reach a specified destination speed (s2) after accelerating
* from initial speed s1 without ever stopping at a plateau:
* When to start braking (di) to reach a specified destination speed (s2) after
* acceleration from initial speed s1 without ever reaching a plateau:
* Solve[{DestinationSpeed[s1, a, di] == DestinationSpeed[s2, a, d - di]}, di]
* di -> (2 a d - s1^2 + s2^2)/(4 a) --> intersection_distance()
* di -> (2 a d - s1^2 + s2^2)/(4 a)
*
* IntersectionDistance[s1_, s2_, a_, d_] := (2 a d - s1^2 + s2^2)/(4 a)
* We note, as an optimization, that if we have already calculated an
* acceleration distance d1 from s1 to m and a deceration distance d2
* from m to s2 then
*
* --
*
* The fast inverse function needed for Bézier interpolation for AVR
* was designed, written and tested by Eduardo José Tagle on April/2018
* d1 -> (m^2 - s1^2) / (2 a)
* d2 -> (m^2 - s2^2) / (2 a)
* di -> (d + d1 - d2) / 2
*/
#include "planner.h"
@ -211,7 +214,7 @@ xyze_long_t Planner::position{0};
uint32_t Planner::acceleration_long_cutoff;
xyze_float_t Planner::previous_speed;
float Planner::previous_nominal_speed_sqr;
float Planner::previous_nominal_speed;
#if ENABLED(DISABLE_INACTIVE_EXTRUDER)
last_move_t Planner::g_uc_extruder_last_move[E_STEPPERS] = { 0 };
@ -220,7 +223,7 @@ float Planner::previous_nominal_speed_sqr;
#ifdef XY_FREQUENCY_LIMIT
int8_t Planner::xy_freq_limit_hz = XY_FREQUENCY_LIMIT;
float Planner::xy_freq_min_speed_factor = (XY_FREQUENCY_MIN_PERCENT) * 0.01f;
int32_t Planner::xy_freq_min_interval_us = LROUND(1000000.0 / (XY_FREQUENCY_LIMIT));
int32_t Planner::xy_freq_min_interval_us = LROUND(1000000.0f / (XY_FREQUENCY_LIMIT));
#endif
#if ENABLED(LIN_ADVANCE)
@ -250,7 +253,7 @@ void Planner::init() {
TERN_(HAS_POSITION_FLOAT, position_float.reset());
TERN_(IS_KINEMATIC, position_cart.reset());
previous_speed.reset();
previous_nominal_speed_sqr = 0;
previous_nominal_speed = 0;
TERN_(ABL_PLANAR, bed_level_matrix.set_to_identity());
clear_block_buffer();
delay_before_delivering = 0;
@ -786,41 +789,48 @@ void Planner::calculate_trapezoid_for_block(block_t * const block, const_float_t
NOLESS(final_rate, uint32_t(MINIMAL_STEP_RATE));
#if ENABLED(S_CURVE_ACCELERATION)
uint32_t cruise_rate = initial_rate;
// If we have some plateau time, the cruise rate will be the nominal rate
uint32_t cruise_rate = block->nominal_rate;
#endif
const int32_t accel = block->acceleration_steps_per_s2;
// Steps for acceleration, plateau and deceleration
int32_t plateau_steps = block->step_event_count;
uint32_t accelerate_steps = 0,
decelerate_steps = 0;
if (accel != 0) {
// Steps required for acceleration, deceleration to/from nominal rate
uint32_t accelerate_steps = CEIL(estimate_acceleration_distance(initial_rate, block->nominal_rate, accel)),
decelerate_steps = FLOOR(estimate_acceleration_distance(block->nominal_rate, final_rate, -accel));
const float nominal_rate_sq = sq(float(block->nominal_rate));
float accelerate_steps_float = (nominal_rate_sq - sq(float(initial_rate))) * (0.5f / accel);
accelerate_steps = CEIL(accelerate_steps_float);
const float decelerate_steps_float = (nominal_rate_sq - sq(float(final_rate))) * (0.5f / accel);
decelerate_steps = decelerate_steps_float;
// Steps between acceleration and deceleration, if any
int32_t plateau_steps = block->step_event_count - accelerate_steps - decelerate_steps;
plateau_steps -= accelerate_steps + decelerate_steps;
// Does accelerate_steps + decelerate_steps exceed step_event_count?
// Then we can't possibly reach the nominal rate, there will be no cruising.
// Use intersection_distance() to calculate accel / braking time in order to
// reach the final_rate exactly at the end of this block.
// Calculate accel / braking time in order to reach the final_rate exactly
// at the end of this block.
if (plateau_steps < 0) {
const float accelerate_steps_float = CEIL(intersection_distance(initial_rate, final_rate, accel, block->step_event_count));
accelerate_steps_float = CEIL((block->step_event_count + accelerate_steps_float - decelerate_steps_float) * 0.5f);
accelerate_steps = _MIN(uint32_t(_MAX(accelerate_steps_float, 0)), block->step_event_count);
decelerate_steps = block->step_event_count - accelerate_steps;
plateau_steps = 0;
#if ENABLED(S_CURVE_ACCELERATION)
// We won't reach the cruising rate. Let's calculate the speed we will reach
cruise_rate = final_speed(initial_rate, accel, accelerate_steps);
#endif
}
#if ENABLED(S_CURVE_ACCELERATION)
else // We have some plateau time, so the cruise rate will be the nominal rate
cruise_rate = block->nominal_rate;
#endif
}
#if ENABLED(S_CURVE_ACCELERATION)
// Jerk controlled speed requires to express speed versus time, NOT steps
uint32_t acceleration_time = ((float)(cruise_rate - initial_rate) / accel) * (STEPPER_TIMER_RATE),
deceleration_time = ((float)(cruise_rate - final_rate) / accel) * (STEPPER_TIMER_RATE),
uint32_t acceleration_time = (float(cruise_rate - initial_rate) / accel) * (STEPPER_TIMER_RATE),
deceleration_time = (float(cruise_rate - final_rate) / accel) * (STEPPER_TIMER_RATE),
// And to offload calculations from the ISR, we also calculate the inverse of those times here
acceleration_time_inverse = get_period_inverse(acceleration_time),
deceleration_time_inverse = get_period_inverse(deceleration_time);
@ -1175,7 +1185,7 @@ void Planner::recalculate_trapezoids(TERN_(HINTS_SAFE_EXIT_SPEED, const_float_t
// Go from the tail (currently executed block) to the first block, without including it)
block_t *block = nullptr, *next = nullptr;
float current_entry_speed = 0.0, next_entry_speed = 0.0;
float current_entry_speed = 0.0f, next_entry_speed = 0.0f;
while (block_index != head_block_index) {
next = &block_buffer[block_index];
@ -1199,13 +1209,12 @@ void Planner::recalculate_trapezoids(TERN_(HINTS_SAFE_EXIT_SPEED, const_float_t
// Block is not BUSY, we won the race against the Stepper ISR:
// NOTE: Entry and exit factors always > 0 by all previous logic operations.
const float current_nominal_speed = SQRT(block->nominal_speed_sqr),
nomr = 1.0f / current_nominal_speed;
const float nomr = 1.0f / block->nominal_speed;
calculate_trapezoid_for_block(block, current_entry_speed * nomr, next_entry_speed * nomr);
#if ENABLED(LIN_ADVANCE)
if (block->use_advance_lead) {
const float comp = block->e_D_ratio * extruder_advance_K[active_extruder] * settings.axis_steps_per_mm[E_AXIS];
block->max_adv_steps = current_nominal_speed * comp;
block->max_adv_steps = block->nominal_speed * comp;
block->final_adv_steps = next_entry_speed * comp;
}
#endif
@ -1240,13 +1249,12 @@ void Planner::recalculate_trapezoids(TERN_(HINTS_SAFE_EXIT_SPEED, const_float_t
if (!stepper.is_block_busy(block)) {
// Block is not BUSY, we won the race against the Stepper ISR:
const float current_nominal_speed = SQRT(block->nominal_speed_sqr),
nomr = 1.0f / current_nominal_speed;
const float nomr = 1.0f / block->nominal_speed;
calculate_trapezoid_for_block(block, current_entry_speed * nomr, next_entry_speed * nomr);
#if ENABLED(LIN_ADVANCE)
if (block->use_advance_lead) {
const float comp = block->e_D_ratio * extruder_advance_K[active_extruder] * settings.axis_steps_per_mm[E_AXIS];
block->max_adv_steps = current_nominal_speed * comp;
block->max_adv_steps = block->nominal_speed * comp;
block->final_adv_steps = next_entry_speed * comp;
}
#endif
@ -1290,14 +1298,10 @@ void Planner::recalculate(TERN_(HINTS_SAFE_EXIT_SPEED, const_float_t safe_exit_s
#define FAN_SET(F) do{ kickstart_fan(fan_speed, ms, F); _FAN_SET(F); }while(0)
const millis_t ms = millis();
TERN_(HAS_FAN0, FAN_SET(0));
TERN_(HAS_FAN1, FAN_SET(1));
TERN_(HAS_FAN2, FAN_SET(2));
TERN_(HAS_FAN3, FAN_SET(3));
TERN_(HAS_FAN4, FAN_SET(4));
TERN_(HAS_FAN5, FAN_SET(5));
TERN_(HAS_FAN6, FAN_SET(6));
TERN_(HAS_FAN7, FAN_SET(7));
TERN_(HAS_FAN0, FAN_SET(0)); TERN_(HAS_FAN1, FAN_SET(1));
TERN_(HAS_FAN2, FAN_SET(2)); TERN_(HAS_FAN3, FAN_SET(3));
TERN_(HAS_FAN4, FAN_SET(4)); TERN_(HAS_FAN5, FAN_SET(5));
TERN_(HAS_FAN6, FAN_SET(6)); TERN_(HAS_FAN7, FAN_SET(7));
}
#if FAN_KICKSTART_TIME
@ -1485,7 +1489,7 @@ void Planner::check_axes_activity() {
for (uint8_t b = block_buffer_tail; b != block_buffer_head; b = next_block_index(b)) {
const block_t * const block = &block_buffer[b];
if (NUM_AXIS_GANG(block->steps.x, || block->steps.y, || block->steps.z, || block->steps.i, || block->steps.j, || block->steps.k, || block->steps.u, || block->steps.v, || block->steps.w)) {
const float se = (float)block->steps.e / block->step_event_count * SQRT(block->nominal_speed_sqr); // mm/sec;
const float se = float(block->steps.e) / block->step_event_count * block->nominal_speed; // mm/sec
NOLESS(high, se);
}
}
@ -1936,7 +1940,7 @@ bool Planner::_populate_block(
#if ENABLED(MIXING_EXTRUDER)
bool ignore_e = false;
float collector[MIXING_STEPPERS];
mixer.refresh_collector(1.0, mixer.get_current_vtool(), collector);
mixer.refresh_collector(1.0f, mixer.get_current_vtool(), collector);
MIXER_STEPPER_LOOP(e)
if (e_steps * collector[e] > max_e_steps) { ignore_e = true; break; }
#else
@ -2193,7 +2197,7 @@ bool Planner::_populate_block(
#if SECONDARY_LINEAR_AXES >= 1 && NONE(FOAMCUTTER_XYUV, ARTICULATED_ROBOT_ARM)
if (NEAR_ZERO(distance_sqr)) {
// Move does not involve any primary linear axes (xyz) but might involve secondary linear axes
distance_sqr = (0.0
distance_sqr = (0.0f
SECONDARY_AXIS_GANG(
IF_DISABLED(AXIS4_ROTATES, + sq(steps_dist_mm.i)),
IF_DISABLED(AXIS5_ROTATES, + sq(steps_dist_mm.j)),
@ -2396,7 +2400,7 @@ bool Planner::_populate_block(
if (was_enabled) stepper.wake_up();
#endif
block->nominal_speed_sqr = sq(block->millimeters * inverse_secs); // (mm/sec)^2 Always > 0
block->nominal_speed = block->millimeters * inverse_secs; // (mm/sec) Always > 0
block->nominal_rate = CEIL(block->step_event_count * inverse_secs); // (step/sec) Always > 0
#if ENABLED(FILAMENT_WIDTH_SENSOR)
@ -2492,7 +2496,7 @@ bool Planner::_populate_block(
if (speed_factor < 1.0f) {
current_speed *= speed_factor;
block->nominal_rate *= speed_factor;
block->nominal_speed_sqr = block->nominal_speed_sqr * sq(speed_factor);
block->nominal_speed *= speed_factor;
}
// Compute and limit the acceleration rate for the trapezoid generator.
@ -2592,7 +2596,7 @@ bool Planner::_populate_block(
if (block->use_advance_lead) {
block->advance_speed = (STEPPER_TIMER_RATE) / (extruder_advance_K[active_extruder] * block->e_D_ratio * block->acceleration * settings.axis_steps_per_mm[E_AXIS_N(extruder)]);
#if ENABLED(LA_DEBUG)
if (extruder_advance_K[active_extruder] * block->e_D_ratio * block->acceleration * 2 < SQRT(block->nominal_speed_sqr) * block->e_D_ratio)
if (extruder_advance_K[active_extruder] * block->e_D_ratio * block->acceleration * 2 < block->nominal_speed * block->e_D_ratio)
SERIAL_ECHOLNPGM("More than 2 steps per eISR loop executed.");
if (block->advance_speed < 200)
SERIAL_ECHOLNPGM("eISR running at > 10kHz.");
@ -2663,7 +2667,7 @@ bool Planner::_populate_block(
unit_vec *= inverse_millimeters; // Use pre-calculated (1 / SQRT(x^2 + y^2 + z^2))
// Skip first block or when previous_nominal_speed is used as a flag for homing and offset cycles.
if (moves_queued && !UNEAR_ZERO(previous_nominal_speed_sqr)) {
if (moves_queued && !UNEAR_ZERO(previous_nominal_speed)) {
// Compute cosine of angle between previous and current path. (prev_unit_vec is negative)
// NOTE: Max junction velocity is computed without sin() or acos() by trig half angle identity.
float junction_cos_theta = LOGICAL_AXIS_GANG(
@ -2792,7 +2796,7 @@ bool Planner::_populate_block(
}
// Get the lowest speed
vmax_junction_sqr = _MIN(vmax_junction_sqr, block->nominal_speed_sqr, previous_nominal_speed_sqr);
vmax_junction_sqr = _MIN(vmax_junction_sqr, sq(block->nominal_speed), sq(previous_nominal_speed));
}
else // Init entry speed to zero. Assume it starts from rest. Planner will correct this later.
vmax_junction_sqr = 0;
@ -2801,27 +2805,17 @@ bool Planner::_populate_block(
#endif
#ifdef USE_CACHED_SQRT
#define CACHED_SQRT(N, V) \
static float saved_V, N; \
if (V != saved_V) { N = SQRT(V); saved_V = V; }
#else
#define CACHED_SQRT(N, V) const float N = SQRT(V)
#endif
#if HAS_CLASSIC_JERK
/**
* Adapted from Průša MKS firmware
* https://github.com/prusa3d/Prusa-Firmware
*/
CACHED_SQRT(nominal_speed, block->nominal_speed_sqr);
// Exit speed limited by a jerk to full halt of a previous last segment
static float previous_safe_speed;
// Start with a safe speed (from which the machine may halt to stop immediately).
float safe_speed = nominal_speed;
float safe_speed = block->nominal_speed;
#ifndef TRAVEL_EXTRA_XYJERK
#define TRAVEL_EXTRA_XYJERK 0
@ -2834,7 +2828,7 @@ bool Planner::_populate_block(
maxj = (max_jerk[i] + (i == X_AXIS || i == Y_AXIS ? extra_xyjerk : 0.0f)); // mj : The max jerk setting for this axis
if (jerk > maxj) { // cs > mj : New current speed too fast?
if (limited) { // limited already?
const float mjerk = nominal_speed * maxj; // ns*mj
const float mjerk = block->nominal_speed * maxj; // ns*mj
if (jerk * safe_speed > mjerk) safe_speed = mjerk / jerk; // ns*mj/cs
}
else {
@ -2845,7 +2839,7 @@ bool Planner::_populate_block(
}
float vmax_junction;
if (moves_queued && !UNEAR_ZERO(previous_nominal_speed_sqr)) {
if (moves_queued && !UNEAR_ZERO(previous_nominal_speed)) {
// Estimate a maximum velocity allowed at a joint of two successive segments.
// If this maximum velocity allowed is lower than the minimum of the entry / exit safe velocities,
// then the machine is not coasting anymore and the safe entry / exit velocities shall be used.
@ -2856,11 +2850,9 @@ bool Planner::_populate_block(
// The junction velocity will be shared between successive segments. Limit the junction velocity to their minimum.
// Pick the smaller of the nominal speeds. Higher speed shall not be achieved at the junction during coasting.
CACHED_SQRT(previous_nominal_speed, previous_nominal_speed_sqr);
float smaller_speed_factor = 1.0f;
if (nominal_speed < previous_nominal_speed) {
vmax_junction = nominal_speed;
if (block->nominal_speed < previous_nominal_speed) {
vmax_junction = block->nominal_speed;
smaller_speed_factor = vmax_junction / previous_nominal_speed;
}
else
@ -2927,11 +2919,11 @@ bool Planner::_populate_block(
// block nominal speed limits both the current and next maximum junction speeds. Hence, in both
// the reverse and forward planners, the corresponding block junction speed will always be at the
// the maximum junction speed and may always be ignored for any speed reduction checks.
block->flag.set_nominal(block->nominal_speed_sqr <= v_allowable_sqr);
block->flag.set_nominal(sq(block->nominal_speed) <= v_allowable_sqr);
// Update previous path unit_vector and nominal speed
previous_speed = current_speed;
previous_nominal_speed_sqr = block->nominal_speed_sqr;
previous_nominal_speed = block->nominal_speed;
position = target; // Update the position
@ -3268,7 +3260,7 @@ void Planner::set_machine_position_mm(const abce_pos_t &abce) {
);
if (has_blocks_queued()) {
//previous_nominal_speed_sqr = 0.0; // Reset planner junction speeds. Assume start from rest.
//previous_nominal_speed = 0.0f; // Reset planner junction speeds. Assume start from rest.
//previous_speed.reset();
buffer_sync_block(BLOCK_BIT_SYNC_POSITION);
}
@ -3344,7 +3336,7 @@ void Planner::refresh_positioning() {
inline void limit_and_warn(float &val, const AxisEnum axis, PGM_P const setting_name, const xyze_float_t &max_limit) {
const uint8_t lim_axis = TERN_(HAS_EXTRUDERS, axis > E_AXIS ? E_AXIS :) axis;
const float before = val;
LIMIT(val, 0.1, max_limit[lim_axis]);
LIMIT(val, 0.1f, max_limit[lim_axis]);
if (before != val) {
SERIAL_CHAR(AXIS_CHAR(lim_axis));
SERIAL_ECHOPGM(" Max ");

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@ -199,7 +199,7 @@ typedef struct PlannerBlock {
volatile bool is_move() { return !(is_sync() || is_page()); }
// Fields used by the motion planner to manage acceleration
float nominal_speed_sqr, // The nominal speed for this block in (mm/sec)^2
float nominal_speed, // The nominal speed for this block in (mm/sec)
entry_speed_sqr, // Entry speed at previous-current junction in (mm/sec)^2
max_entry_speed_sqr, // Maximum allowable junction entry speed in (mm/sec)^2
millimeters, // The total travel of this block in mm
@ -510,7 +510,7 @@ class Planner {
/**
* Nominal speed of previous path line segment (mm/s)^2
*/
static float previous_nominal_speed_sqr;
static float previous_nominal_speed;
/**
* Limit where 64bit math is necessary for acceleration calculation
@ -1009,28 +1009,6 @@ class Planner {
static constexpr uint8_t next_block_index(const uint8_t block_index) { return BLOCK_MOD(block_index + 1); }
static constexpr uint8_t prev_block_index(const uint8_t block_index) { return BLOCK_MOD(block_index - 1); }
/**
* Calculate the distance (not time) it takes to accelerate
* from initial_rate to target_rate using the given acceleration:
*/
static float estimate_acceleration_distance(const_float_t initial_rate, const_float_t target_rate, const_float_t accel) {
if (accel == 0) return 0; // accel was 0, set acceleration distance to 0
return (sq(target_rate) - sq(initial_rate)) / (accel * 2);
}
/**
* Return the point at which you must start braking (at the rate of -'accel') if
* you start at 'initial_rate', accelerate (until reaching the point), and want to end at
* 'final_rate' after traveling 'distance'.
*
* This is used to compute the intersection point between acceleration and deceleration
* in cases where the "trapezoid" has no plateau (i.e., never reaches maximum speed)
*/
static float intersection_distance(const_float_t initial_rate, const_float_t final_rate, const_float_t accel, const_float_t distance) {
if (accel == 0) return 0; // accel was 0, set intersection distance to 0
return (accel * 2 * distance - sq(initial_rate) + sq(final_rate)) / (accel * 4);
}
/**
* Calculate the maximum allowable speed squared at this point, in order
* to reach 'target_velocity_sqr' using 'acceleration' within a given