move the tick_info array into AHB0 to save memory
[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 in AHB0 to save memory
77 tick_info= (tickinfo_t *)AHB0.alloc(sizeof(tickinfo_t) * n_actuators);
78 }
79
80 for(int i = 0; i < n_actuators; ++i) {
81 tick_info[i].steps_per_tick= 0;
82 tick_info[i].counter= 0;
83 tick_info[i].acceleration_change= 0;
84 tick_info[i].deceleration_change= 0;
85 tick_info[i].plateau_rate= 0;
86 tick_info[i].steps_to_move= 0;
87 tick_info[i].step_count= 0;
88 tick_info[i].next_accel_event= 0;
89 }
90 }
91
92 void Block::debug() const
93 {
94 THEKERNEL->streams->printf("%p: steps-X:%lu Y:%lu Z:%lu ", this, this->steps[0], this->steps[1], this->steps[2]);
95 for (size_t i = E_AXIS; i < n_actuators; ++i) {
96 THEKERNEL->streams->printf("%c:%lu ", 'A' + i-E_AXIS, this->steps[i]);
97 }
98 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",
99 this->steps_event_count,
100 this->nominal_rate,
101 this->nominal_speed,
102 this->millimeters,
103 this->acceleration,
104 this->accelerate_until,
105 this->decelerate_after,
106 this->total_move_ticks,
107 this->initial_rate,
108 this->maximum_rate,
109 this->entry_speed,
110 this->max_entry_speed,
111 this->exit_speed,
112 this->primary_axis,
113 this->is_ready,
114 this->locked,
115 this->is_ticking,
116 recalculate_flag ? 1 : 0,
117 nominal_length_flag ? 1 : 0,
118 total_move_ticks/STEP_TICKER_FREQUENCY
119 );
120 }
121
122
123 /* Calculates trapezoid parameters so that the entry- and exit-speed is compensated by the provided factors.
124 // The factors represent a factor of braking and must be in the range 0.0-1.0.
125 // +--------+ <- nominal_rate
126 // / \
127 // nominal_rate*entry_factor -> + \
128 // | + <- nominal_rate*exit_factor
129 // +-------------+
130 // time -->
131 */
132 void Block::calculate_trapezoid( float entryspeed, float exitspeed )
133 {
134 // if block is currently executing, don't touch anything!
135 if (is_ticking) return;
136
137 float initial_rate = this->nominal_rate * (entryspeed / this->nominal_speed); // steps/sec
138 float final_rate = this->nominal_rate * (exitspeed / this->nominal_speed);
139 //printf("Initial rate: %f, final_rate: %f\n", initial_rate, final_rate);
140 // How many steps ( can be fractions of steps, we need very precise values ) to accelerate and decelerate
141 // This is a simplification to get rid of rate_delta and get the steps/s² accel directly from the mm/s² accel
142 float acceleration_per_second = (this->acceleration * this->steps_event_count) / this->millimeters;
143
144 float maximum_possible_rate = sqrtf( ( this->steps_event_count * acceleration_per_second ) + ( ( powf(initial_rate, 2) + powf(final_rate, 2) ) / 2.0F ) );
145
146 //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);
147
148 // Now this is the maximum rate we'll achieve this move, either because
149 // it's the higher we can achieve, or because it's the higher we are
150 // allowed to achieve
151 this->maximum_rate = std::min(maximum_possible_rate, this->nominal_rate);
152
153 // Now figure out how long it takes to accelerate in seconds
154 float time_to_accelerate = ( this->maximum_rate - initial_rate ) / acceleration_per_second;
155
156 // Now figure out how long it takes to decelerate
157 float time_to_decelerate = ( final_rate - this->maximum_rate ) / -acceleration_per_second;
158
159 // Now we know how long it takes to accelerate and decelerate, but we must
160 // also know how long the entire move takes so we can figure out how long
161 // is the plateau if there is one
162 float plateau_time = 0;
163
164 // Only if there is actually a plateau ( we are limited by nominal_rate )
165 if(maximum_possible_rate > this->nominal_rate) {
166 // Figure out the acceleration and deceleration distances ( in steps )
167 float acceleration_distance = ( ( initial_rate + this->maximum_rate ) / 2.0F ) * time_to_accelerate;
168 float deceleration_distance = ( ( this->maximum_rate + final_rate ) / 2.0F ) * time_to_decelerate;
169
170 // Figure out the plateau steps
171 float plateau_distance = this->steps_event_count - acceleration_distance - deceleration_distance;
172
173 // Figure out the plateau time in seconds
174 plateau_time = plateau_distance / this->maximum_rate;
175 }
176
177 // Figure out how long the move takes total ( in seconds )
178 float total_move_time = time_to_accelerate + time_to_decelerate + plateau_time;
179 //puts "total move time: #{total_move_time}s time to accelerate: #{time_to_accelerate}, time to decelerate: #{time_to_decelerate}"
180
181 // We now have the full timing for acceleration, plateau and deceleration,
182 // yay \o/ Now this is very important these are in seconds, and we need to
183 // round them into ticks. This means instead of accelerating in 100.23
184 // ticks we'll accelerate in 100 ticks. Which means to reach the exact
185 // speed we want to reach, we must figure out a new/slightly different
186 // acceleration/deceleration to be sure we accelerate and decelerate at
187 // the exact rate we want
188
189 // First off round total time, acceleration time and deceleration time in ticks
190 uint32_t acceleration_ticks = floorf( time_to_accelerate * STEP_TICKER_FREQUENCY );
191 uint32_t deceleration_ticks = floorf( time_to_decelerate * STEP_TICKER_FREQUENCY );
192 uint32_t total_move_ticks = floorf( total_move_time * STEP_TICKER_FREQUENCY );
193
194 // Now deduce the plateau time for those new values expressed in tick
195 //uint32_t plateau_ticks = total_move_ticks - acceleration_ticks - deceleration_ticks;
196
197 // Now we figure out the acceleration value to reach EXACTLY maximum_rate(steps/s) in EXACTLY acceleration_ticks(ticks) amount of time in seconds
198 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
199 float deceleration_time = deceleration_ticks / STEP_TICKER_FREQUENCY;
200
201 float acceleration_in_steps = (acceleration_time > 0.0F ) ? ( this->maximum_rate - initial_rate ) / acceleration_time : 0;
202 float deceleration_in_steps = (deceleration_time > 0.0F ) ? ( this->maximum_rate - final_rate ) / deceleration_time : 0;
203
204 // we have a potential race condition here as we could get interrupted anywhere in the middle of this call, we need to lock
205 // the updates to the blocks to get around it
206 this->locked= true;
207 // Now figure out the two acceleration ramp change events in ticks
208 this->accelerate_until = acceleration_ticks;
209 this->decelerate_after = total_move_ticks - deceleration_ticks;
210
211 // We now have everything we need for this block to call a Steppermotor->move method !!!!
212 // Theorically, if accel is done per tick, the speed curve should be perfect.
213 this->total_move_ticks = total_move_ticks;
214
215 this->initial_rate = initial_rate;
216 this->exit_speed = exitspeed;
217
218 // prepare the block for stepticker
219 this->prepare(acceleration_in_steps, deceleration_in_steps);
220
221 this->locked= false;
222 }
223
224 // Calculates the maximum allowable speed at this point when you must be able to reach target_velocity using the
225 // acceleration within the allotted distance.
226 float Block::max_allowable_speed(float acceleration, float target_velocity, float distance)
227 {
228 return sqrtf(target_velocity * target_velocity - 2.0F * acceleration * distance);
229 }
230
231 // Called by Planner::recalculate() when scanning the plan from last to first entry.
232 float Block::reverse_pass(float exit_speed)
233 {
234 // If entry speed is already at the maximum entry speed, no need to recheck. Block is cruising.
235 // If not, block in state of acceleration or deceleration. Reset entry speed to maximum and
236 // check for maximum allowable speed reductions to ensure maximum possible planned speed.
237 if (this->entry_speed != this->max_entry_speed) {
238 // If nominal length true, max junction speed is guaranteed to be reached. Only compute
239 // for max allowable speed if block is decelerating and nominal length is false.
240 if ((!this->nominal_length_flag) && (this->max_entry_speed > exit_speed)) {
241 float max_entry_speed = max_allowable_speed(-this->acceleration, exit_speed, this->millimeters);
242
243 this->entry_speed = min(max_entry_speed, this->max_entry_speed);
244
245 return this->entry_speed;
246 } else
247 this->entry_speed = this->max_entry_speed;
248 }
249
250 return this->entry_speed;
251 }
252
253
254 // Called by Planner::recalculate() when scanning the plan from first to last entry.
255 // returns maximum exit speed of this block
256 float Block::forward_pass(float prev_max_exit_speed)
257 {
258 // If the previous block is an acceleration block, but it is not long enough to complete the
259 // full speed change within the block, we need to adjust the entry speed accordingly. Entry
260 // speeds have already been reset, maximized, and reverse planned by reverse planner.
261 // If nominal length is true, max junction speed is guaranteed to be reached. No need to recheck.
262
263 // TODO: find out if both of these checks are necessary
264 if (prev_max_exit_speed > nominal_speed)
265 prev_max_exit_speed = nominal_speed;
266 if (prev_max_exit_speed > max_entry_speed)
267 prev_max_exit_speed = max_entry_speed;
268
269 if (prev_max_exit_speed <= entry_speed) {
270 // accel limited
271 entry_speed = prev_max_exit_speed;
272 // since we're now acceleration or cruise limited
273 // we don't need to recalculate our entry speed anymore
274 recalculate_flag = false;
275 }
276 // else
277 // // decel limited, do nothing
278
279 return max_exit_speed();
280 }
281
282 float Block::max_exit_speed()
283 {
284 // if block is currently executing, return cached exit speed from calculate_trapezoid
285 // this ensures that a block following a currently executing block will have correct entry speed
286 if(is_ticking)
287 return this->exit_speed;
288
289 // if nominal_length_flag is asserted
290 // we are guaranteed to reach nominal speed regardless of entry speed
291 // thus, max exit will always be nominal
292 if (nominal_length_flag)
293 return nominal_speed;
294
295 // otherwise, we have to work out max exit speed based on entry and acceleration
296 float max = max_allowable_speed(-this->acceleration, this->entry_speed, this->millimeters);
297
298 return min(max, nominal_speed);
299 }
300
301 // prepare block for the step ticker, called everytime the block changes
302 // this is done during planning so does not delay tick generation and step ticker can simply grab the next block during the interrupt
303 void Block::prepare(float acceleration_in_steps, float deceleration_in_steps)
304 {
305
306 float inv = 1.0F / this->steps_event_count;
307
308 // Now figure out the acceleration PER TICK, this should ideally be held as a double as it's very critical to the block timing
309 // steps/tick^2
310 // was....
311 // float acceleration_per_tick = acceleration_in_steps / STEP_TICKER_FREQUENCY_2; // that is 100,000² too big for a float
312 // float deceleration_per_tick = deceleration_in_steps / STEP_TICKER_FREQUENCY_2;
313 double acceleration_per_tick = acceleration_in_steps * fp_scale; // this is now scaled to fit a 2.30 fixed point number
314 double deceleration_per_tick = deceleration_in_steps * fp_scale;
315
316 for (uint8_t m = 0; m < n_actuators; m++) {
317 uint32_t steps = this->steps[m];
318 this->tick_info[m].steps_to_move = steps;
319 if(steps == 0) continue;
320
321 float aratio = inv * steps;
322
323 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
324 this->tick_info[m].counter = 0; // 2.62 fixed point
325 this->tick_info[m].step_count = 0;
326 this->tick_info[m].next_accel_event = this->total_move_ticks + 1;
327
328 double acceleration_change = 0;
329 if(this->accelerate_until != 0) { // If the next accel event is the end of accel
330 this->tick_info[m].next_accel_event = this->accelerate_until;
331 acceleration_change = acceleration_per_tick;
332
333 } else if(this->decelerate_after == 0 /*&& this->accelerate_until == 0*/) {
334 // we start off decelerating
335 acceleration_change = -deceleration_per_tick;
336
337 } else if(this->decelerate_after != this->total_move_ticks /*&& this->accelerate_until == 0*/) {
338 // If the next event is the start of decel ( don't set this if the next accel event is accel end )
339 this->tick_info[m].next_accel_event = this->decelerate_after;
340 }
341
342 // already converted to fixed point just needs scaling by ratio
343 //#define STEPTICKER_TOFP(x) ((int64_t)round((double)(x)*STEPTICKER_FPSCALE))
344 this->tick_info[m].acceleration_change= (int64_t)round(acceleration_change * aratio);
345 this->tick_info[m].deceleration_change= -(int64_t)round(deceleration_per_tick * aratio);
346 this->tick_info[m].plateau_rate= (int64_t)round(((this->maximum_rate * aratio) / STEP_TICKER_FREQUENCY) * STEPTICKER_FPSCALE);
347
348 #if 0
349 THEKERNEL->streams->printf("spt: %08lX %08lX, ac: %08lX %08lX, dc: %08lX %08lX, pr: %08lX %08lX\n",
350 (uint32_t)(this->tick_info[m].steps_per_tick>>32), // 2.62 fixed point
351 (uint32_t)(this->tick_info[m].steps_per_tick&0xFFFFFFFF), // 2.62 fixed point
352 (uint32_t)(this->tick_info[m].acceleration_change>>32), // 2.62 fixed point signed
353 (uint32_t)(this->tick_info[m].acceleration_change&0xFFFFFFFF), // 2.62 fixed point signed
354 (uint32_t)(this->tick_info[m].deceleration_change>>32), // 2.62 fixed point
355 (uint32_t)(this->tick_info[m].deceleration_change&0xFFFFFFFF), // 2.62 fixed point
356 (uint32_t)(this->tick_info[m].plateau_rate>>32), // 2.62 fixed point
357 (uint32_t)(this->tick_info[m].plateau_rate&0xFFFFFFFF) // 2.62 fixed point
358 );
359 #endif
360 }
361 }
362
363 // returns current rate (steps/sec) for the given actuator
364 float Block::get_trapezoid_rate(int i) const
365 {
366 // convert steps per tick from fixed point to float and convert to steps/sec
367 // FIXME steps_per_tick can change at any time, potential race condition if it changes while being read here
368 return STEPTICKER_FROMFP(tick_info[i].steps_per_tick) * STEP_TICKER_FREQUENCY;
369 }