Merge remote-tracking branch 'upstream/edge' into feature/soft-endstops
[clinton/Smoothieware.git] / src / modules / robot / Block.cpp
1 /*
2 This file is part of Smoothie (http://smoothieware.org/). The motion control part is heavily based on Grbl (https://github.com/simen/grbl).
3 Smoothie 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.
4 Smoothie 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.
5 You should have received a copy of the GNU General Public License along with Smoothie. If not, see <http://www.gnu.org/licenses/>.
6 */
7
8 #include "libs/Module.h"
9 #include "libs/Kernel.h"
10 #include "libs/nuts_bolts.h"
11 #include <cmath>
12 #include <string>
13 #include "Block.h"
14 #include "Planner.h"
15 #include "Conveyor.h"
16 #include "Gcode.h"
17 #include "libs/StreamOutputPool.h"
18 #include "StepTicker.h"
19 #include "platform_memory.h"
20
21 #include "mri.h"
22 #include <inttypes.h>
23
24 using std::string;
25 #include <vector>
26
27 #define STEP_TICKER_FREQUENCY THEKERNEL->step_ticker->get_frequency()
28
29 uint8_t Block::n_actuators= 0;
30 double Block::fp_scale= 0;
31
32 // A block represents a movement, it's length for each stepper motor, and the corresponding acceleration curves.
33 // It's stacked on a queue, and that queue is then executed in order, to move the motors.
34 // Most of the accel math is also done in this class
35 // And GCode objects for use in on_gcode_execute are also help in here
36
37 Block::Block()
38 {
39 tick_info= nullptr;
40 clear();
41 }
42
43 void Block::init(uint8_t n)
44 {
45 n_actuators= n;
46 fp_scale= (double)STEPTICKER_FPSCALE / pow((double)STEP_TICKER_FREQUENCY, 2.0); // we scale up by fixed point offset first to avoid tiny values
47 }
48
49 void Block::clear()
50 {
51 is_ready = false;
52
53 this->steps.fill(0);
54
55 steps_event_count = 0;
56 nominal_rate = 0.0F;
57 nominal_speed = 0.0F;
58 millimeters = 0.0F;
59 entry_speed = 0.0F;
60 exit_speed = 0.0F;
61 acceleration = 100.0F; // we don't want to get divide by zeroes if this is not set
62 initial_rate = 0.0F;
63 accelerate_until = 0;
64 decelerate_after = 0;
65 direction_bits = 0;
66 recalculate_flag = false;
67 nominal_length_flag = false;
68 max_entry_speed = 0.0F;
69 is_ticking = false;
70 is_g123 = false;
71 locked = false;
72 s_value = 0.0F;
73
74 total_move_ticks= 0;
75 if(tick_info == nullptr) {
76 // we create this once for this block
77 tick_info= new tickinfo_t[n_actuators]; //(tickinfo_t *)malloc(sizeof(tickinfo_t) * n_actuators);
78 if(tick_info == nullptr) {
79 // if we ran out of memory in AHB0 just stop here
80 __debugbreak();
81 }
82 }
83
84 for(int i = 0; i < n_actuators; ++i) {
85 tick_info[i].steps_per_tick= 0;
86 tick_info[i].counter= 0;
87 tick_info[i].acceleration_change= 0;
88 tick_info[i].deceleration_change= 0;
89 tick_info[i].plateau_rate= 0;
90 tick_info[i].steps_to_move= 0;
91 tick_info[i].step_count= 0;
92 tick_info[i].next_accel_event= 0;
93 }
94 }
95
96 void Block::debug() const
97 {
98 THEKERNEL->streams->printf("%p: steps-X:%lu Y:%lu Z:%lu ", this, this->steps[0], this->steps[1], this->steps[2]);
99 for (size_t i = E_AXIS; i < n_actuators; ++i) {
100 THEKERNEL->streams->printf("%c:%lu ", 'A' + i-E_AXIS, this->steps[i]);
101 }
102 THEKERNEL->streams->printf("(max:%lu) nominal:r%1.4f/s%1.4f mm:%1.4f acc:%1.2f accu:%lu decu:%lu ticks:%lu rates:%1.4f/%1.4f entry/max:%1.4f/%1.4f exit:%1.4f primary:%d ready:%d locked:%d ticking:%d recalc:%d nomlen:%d time:%f\r\n",
103 this->steps_event_count,
104 this->nominal_rate,
105 this->nominal_speed,
106 this->millimeters,
107 this->acceleration,
108 this->accelerate_until,
109 this->decelerate_after,
110 this->total_move_ticks,
111 this->initial_rate,
112 this->maximum_rate,
113 this->entry_speed,
114 this->max_entry_speed,
115 this->exit_speed,
116 this->primary_axis,
117 this->is_ready,
118 this->locked,
119 this->is_ticking,
120 recalculate_flag ? 1 : 0,
121 nominal_length_flag ? 1 : 0,
122 total_move_ticks/STEP_TICKER_FREQUENCY
123 );
124 }
125
126
127 /* Calculates trapezoid parameters so that the entry- and exit-speed is compensated by the provided factors.
128 // The factors represent a factor of braking and must be in the range 0.0-1.0.
129 // +--------+ <- nominal_rate
130 // / \
131 // nominal_rate*entry_factor -> + \
132 // | + <- nominal_rate*exit_factor
133 // +-------------+
134 // time -->
135 */
136 void Block::calculate_trapezoid( float entryspeed, float exitspeed )
137 {
138 // if block is currently executing, don't touch anything!
139 if (is_ticking) return;
140
141 float initial_rate = this->nominal_rate * (entryspeed / this->nominal_speed); // steps/sec
142 float final_rate = this->nominal_rate * (exitspeed / this->nominal_speed);
143 //printf("Initial rate: %f, final_rate: %f\n", initial_rate, final_rate);
144 // How many steps ( can be fractions of steps, we need very precise values ) to accelerate and decelerate
145 // This is a simplification to get rid of rate_delta and get the steps/s² accel directly from the mm/s² accel
146 float acceleration_per_second = (this->acceleration * this->steps_event_count) / this->millimeters;
147
148 float maximum_possible_rate = sqrtf( ( this->steps_event_count * acceleration_per_second ) + ( ( powf(initial_rate, 2) + powf(final_rate, 2) ) / 2.0F ) );
149
150 //printf("id %d: acceleration_per_second: %f, maximum_possible_rate: %f steps/sec, %f mm/sec\n", this->id, acceleration_per_second, maximum_possible_rate, maximum_possible_rate/100);
151
152 // Now this is the maximum rate we'll achieve this move, either because
153 // it's the higher we can achieve, or because it's the higher we are
154 // allowed to achieve
155 this->maximum_rate = std::min(maximum_possible_rate, this->nominal_rate);
156
157 // Now figure out how long it takes to accelerate in seconds
158 float time_to_accelerate = ( this->maximum_rate - initial_rate ) / acceleration_per_second;
159
160 // Now figure out how long it takes to decelerate
161 float time_to_decelerate = ( final_rate - this->maximum_rate ) / -acceleration_per_second;
162
163 // Now we know how long it takes to accelerate and decelerate, but we must
164 // also know how long the entire move takes so we can figure out how long
165 // is the plateau if there is one
166 float plateau_time = 0;
167
168 // Only if there is actually a plateau ( we are limited by nominal_rate )
169 if(maximum_possible_rate > this->nominal_rate) {
170 // Figure out the acceleration and deceleration distances ( in steps )
171 float acceleration_distance = ( ( initial_rate + this->maximum_rate ) / 2.0F ) * time_to_accelerate;
172 float deceleration_distance = ( ( this->maximum_rate + final_rate ) / 2.0F ) * time_to_decelerate;
173
174 // Figure out the plateau steps
175 float plateau_distance = this->steps_event_count - acceleration_distance - deceleration_distance;
176
177 // Figure out the plateau time in seconds
178 plateau_time = plateau_distance / this->maximum_rate;
179 }
180
181 // Figure out how long the move takes total ( in seconds )
182 float total_move_time = time_to_accelerate + time_to_decelerate + plateau_time;
183 //puts "total move time: #{total_move_time}s time to accelerate: #{time_to_accelerate}, time to decelerate: #{time_to_decelerate}"
184
185 // We now have the full timing for acceleration, plateau and deceleration,
186 // yay \o/ Now this is very important these are in seconds, and we need to
187 // round them into ticks. This means instead of accelerating in 100.23
188 // ticks we'll accelerate in 100 ticks. Which means to reach the exact
189 // speed we want to reach, we must figure out a new/slightly different
190 // acceleration/deceleration to be sure we accelerate and decelerate at
191 // the exact rate we want
192
193 // First off round total time, acceleration time and deceleration time in ticks
194 uint32_t acceleration_ticks = floorf( time_to_accelerate * STEP_TICKER_FREQUENCY );
195 uint32_t deceleration_ticks = floorf( time_to_decelerate * STEP_TICKER_FREQUENCY );
196 uint32_t total_move_ticks = floorf( total_move_time * STEP_TICKER_FREQUENCY );
197
198 // Now deduce the plateau time for those new values expressed in tick
199 //uint32_t plateau_ticks = total_move_ticks - acceleration_ticks - deceleration_ticks;
200
201 // Now we figure out the acceleration value to reach EXACTLY maximum_rate(steps/s) in EXACTLY acceleration_ticks(ticks) amount of time in seconds
202 float acceleration_time = acceleration_ticks / STEP_TICKER_FREQUENCY; // This can be moved into the operation below, separated for clarity, note we need to do this instead of using time_to_accelerate(seconds) directly because time_to_accelerate(seconds) and acceleration_ticks(seconds) do not have the same value anymore due to the rounding
203 float deceleration_time = deceleration_ticks / STEP_TICKER_FREQUENCY;
204
205 float acceleration_in_steps = (acceleration_time > 0.0F ) ? ( this->maximum_rate - initial_rate ) / acceleration_time : 0;
206 float deceleration_in_steps = (deceleration_time > 0.0F ) ? ( this->maximum_rate - final_rate ) / deceleration_time : 0;
207
208 // we have a potential race condition here as we could get interrupted anywhere in the middle of this call, we need to lock
209 // the updates to the blocks to get around it
210 this->locked= true;
211 // Now figure out the two acceleration ramp change events in ticks
212 this->accelerate_until = acceleration_ticks;
213 this->decelerate_after = total_move_ticks - deceleration_ticks;
214
215 // We now have everything we need for this block to call a Steppermotor->move method !!!!
216 // Theorically, if accel is done per tick, the speed curve should be perfect.
217 this->total_move_ticks = total_move_ticks;
218
219 this->initial_rate = initial_rate;
220 this->exit_speed = exitspeed;
221
222 // prepare the block for stepticker
223 this->prepare(acceleration_in_steps, deceleration_in_steps);
224
225 this->locked= false;
226 }
227
228 // Calculates the maximum allowable speed at this point when you must be able to reach target_velocity using the
229 // acceleration within the allotted distance.
230 float Block::max_allowable_speed(float acceleration, float target_velocity, float distance)
231 {
232 return sqrtf(target_velocity * target_velocity - 2.0F * acceleration * distance);
233 }
234
235 // Called by Planner::recalculate() when scanning the plan from last to first entry.
236 float Block::reverse_pass(float exit_speed)
237 {
238 // If entry speed is already at the maximum entry speed, no need to recheck. Block is cruising.
239 // If not, block in state of acceleration or deceleration. Reset entry speed to maximum and
240 // check for maximum allowable speed reductions to ensure maximum possible planned speed.
241 if (this->entry_speed != this->max_entry_speed) {
242 // If nominal length true, max junction speed is guaranteed to be reached. Only compute
243 // for max allowable speed if block is decelerating and nominal length is false.
244 if ((!this->nominal_length_flag) && (this->max_entry_speed > exit_speed)) {
245 float max_entry_speed = max_allowable_speed(-this->acceleration, exit_speed, this->millimeters);
246
247 this->entry_speed = min(max_entry_speed, this->max_entry_speed);
248
249 return this->entry_speed;
250 } else
251 this->entry_speed = this->max_entry_speed;
252 }
253
254 return this->entry_speed;
255 }
256
257
258 // Called by Planner::recalculate() when scanning the plan from first to last entry.
259 // returns maximum exit speed of this block
260 float Block::forward_pass(float prev_max_exit_speed)
261 {
262 // If the previous block is an acceleration block, but it is not long enough to complete the
263 // full speed change within the block, we need to adjust the entry speed accordingly. Entry
264 // speeds have already been reset, maximized, and reverse planned by reverse planner.
265 // If nominal length is true, max junction speed is guaranteed to be reached. No need to recheck.
266
267 // TODO: find out if both of these checks are necessary
268 if (prev_max_exit_speed > nominal_speed)
269 prev_max_exit_speed = nominal_speed;
270 if (prev_max_exit_speed > max_entry_speed)
271 prev_max_exit_speed = max_entry_speed;
272
273 if (prev_max_exit_speed <= entry_speed) {
274 // accel limited
275 entry_speed = prev_max_exit_speed;
276 // since we're now acceleration or cruise limited
277 // we don't need to recalculate our entry speed anymore
278 recalculate_flag = false;
279 }
280 // else
281 // // decel limited, do nothing
282
283 return max_exit_speed();
284 }
285
286 float Block::max_exit_speed()
287 {
288 // if block is currently executing, return cached exit speed from calculate_trapezoid
289 // this ensures that a block following a currently executing block will have correct entry speed
290 if(is_ticking)
291 return this->exit_speed;
292
293 // if nominal_length_flag is asserted
294 // we are guaranteed to reach nominal speed regardless of entry speed
295 // thus, max exit will always be nominal
296 if (nominal_length_flag)
297 return nominal_speed;
298
299 // otherwise, we have to work out max exit speed based on entry and acceleration
300 float max = max_allowable_speed(-this->acceleration, this->entry_speed, this->millimeters);
301
302 return min(max, nominal_speed);
303 }
304
305 // prepare block for the step ticker, called everytime the block changes
306 // this is done during planning so does not delay tick generation and step ticker can simply grab the next block during the interrupt
307 void Block::prepare(float acceleration_in_steps, float deceleration_in_steps)
308 {
309
310 float inv = 1.0F / this->steps_event_count;
311
312 // Now figure out the acceleration PER TICK, this should ideally be held as a double as it's very critical to the block timing
313 // steps/tick^2
314 // was....
315 // float acceleration_per_tick = acceleration_in_steps / STEP_TICKER_FREQUENCY_2; // that is 100,000² too big for a float
316 // float deceleration_per_tick = deceleration_in_steps / STEP_TICKER_FREQUENCY_2;
317 double acceleration_per_tick = acceleration_in_steps * fp_scale; // this is now scaled to fit a 2.30 fixed point number
318 double deceleration_per_tick = deceleration_in_steps * fp_scale;
319
320 for (uint8_t m = 0; m < n_actuators; m++) {
321 uint32_t steps = this->steps[m];
322 this->tick_info[m].steps_to_move = steps;
323 if(steps == 0) continue;
324
325 float aratio = inv * steps;
326
327 this->tick_info[m].steps_per_tick = (int64_t)round((((double)this->initial_rate * aratio) / STEP_TICKER_FREQUENCY) * STEPTICKER_FPSCALE); // steps/sec / tick frequency to get steps per tick in 2.62 fixed point
328 this->tick_info[m].counter = 0; // 2.62 fixed point
329 this->tick_info[m].step_count = 0;
330 this->tick_info[m].next_accel_event = this->total_move_ticks + 1;
331
332 double acceleration_change = 0;
333 if(this->accelerate_until != 0) { // If the next accel event is the end of accel
334 this->tick_info[m].next_accel_event = this->accelerate_until;
335 acceleration_change = acceleration_per_tick;
336
337 } else if(this->decelerate_after == 0 /*&& this->accelerate_until == 0*/) {
338 // we start off decelerating
339 acceleration_change = -deceleration_per_tick;
340
341 } else if(this->decelerate_after != this->total_move_ticks /*&& this->accelerate_until == 0*/) {
342 // If the next event is the start of decel ( don't set this if the next accel event is accel end )
343 this->tick_info[m].next_accel_event = this->decelerate_after;
344 }
345
346 // already converted to fixed point just needs scaling by ratio
347 //#define STEPTICKER_TOFP(x) ((int64_t)round((double)(x)*STEPTICKER_FPSCALE))
348 this->tick_info[m].acceleration_change= (int64_t)round(acceleration_change * aratio);
349 this->tick_info[m].deceleration_change= -(int64_t)round(deceleration_per_tick * aratio);
350 this->tick_info[m].plateau_rate= (int64_t)round(((this->maximum_rate * aratio) / STEP_TICKER_FREQUENCY) * STEPTICKER_FPSCALE);
351
352 #if 0
353 THEKERNEL->streams->printf("spt: %08lX %08lX, ac: %08lX %08lX, dc: %08lX %08lX, pr: %08lX %08lX\n",
354 (uint32_t)(this->tick_info[m].steps_per_tick>>32), // 2.62 fixed point
355 (uint32_t)(this->tick_info[m].steps_per_tick&0xFFFFFFFF), // 2.62 fixed point
356 (uint32_t)(this->tick_info[m].acceleration_change>>32), // 2.62 fixed point signed
357 (uint32_t)(this->tick_info[m].acceleration_change&0xFFFFFFFF), // 2.62 fixed point signed
358 (uint32_t)(this->tick_info[m].deceleration_change>>32), // 2.62 fixed point
359 (uint32_t)(this->tick_info[m].deceleration_change&0xFFFFFFFF), // 2.62 fixed point
360 (uint32_t)(this->tick_info[m].plateau_rate>>32), // 2.62 fixed point
361 (uint32_t)(this->tick_info[m].plateau_rate&0xFFFFFFFF) // 2.62 fixed point
362 );
363 #endif
364 }
365 }
366
367 // returns current rate (steps/sec) for the given actuator
368 float Block::get_trapezoid_rate(int i) const
369 {
370 // convert steps per tick from fixed point to float and convert to steps/sec
371 // FIXME steps_per_tick can change at any time, potential race condition if it changes while being read here
372 return STEPTICKER_FROMFP(tick_info[i].steps_per_tick) * STEP_TICKER_FREQUENCY;
373 }