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