fix a lot of extruder functionality,
[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 // A block represents a movement, it's length for each stepper motor, and the corresponding acceleration curves.
29 // It's stacked on a queue, and that queue is then executed in order, to move the motors.
30 // Most of the accel math is also done in this class
31 // And GCode objects for use in on_gcode_execute are also help in here
32
33 Block::Block()
34 {
35 clear();
36 }
37
38 void Block::clear()
39 {
40 //commands.clear();
41 //travel_distances.clear();
42 //gcodes.clear();
43 //std::vector<Gcode>().swap(gcodes); // this resizes the vector releasing its memory
44
45 this->steps.fill(0);
46
47 steps_event_count = 0;
48 nominal_rate = 0.0F;
49 nominal_speed = 0.0F;
50 millimeters = 0.0F;
51 entry_speed = 0.0F;
52 exit_speed = 0.0F;
53 acceleration = 100.0F; // we don't want to get divide by zeroes if this is not set
54 initial_rate = 0.0F;
55 accelerate_until = 0;
56 decelerate_after = 0;
57 direction_bits = 0;
58 recalculate_flag = false;
59 nominal_length_flag = false;
60 max_entry_speed = 0.0F;
61 is_ready = false;
62 is_ticking = false;
63 locked = false;
64
65 acceleration_per_tick= 0;
66 deceleration_per_tick= 0;
67 total_move_ticks= 0;
68 for(auto &i : tick_info) {
69 i.steps_per_tick= 0;
70 i.counter= 0;
71 i.acceleration_change= 0;
72 i.deceleration_change= 0;
73 i.plateau_rate= 0;
74 i.steps_to_move= 0;
75 i.step_count= 0;
76 i.next_accel_event= 0;
77 }
78 }
79
80 void Block::debug() const
81 {
82 THEKERNEL->streams->printf("%p: steps-X:%04lu Y:%04lu Z:%04lu ", this, this->steps[0], this->steps[1], this->steps[2]);
83 for (size_t i = E_AXIS; i < k_max_actuators; ++i) {
84 THEKERNEL->streams->printf("E%d:%04lu ", i-E_AXIS, this->steps[i]);
85 }
86 THEKERNEL->streams->printf("(max:%4lu) nominal:r%1.4f/s%1.4f mm:%1.4f acc:%1.2f accu:%5lu decu:%5lu rates:%10.4f entry/max: %10.4f/%10.4f ready:%d locked:%d ticking:%d recalc:%d nomlen:%d time:%f\r\n",
87 this->steps_event_count,
88 this->nominal_rate,
89 this->nominal_speed,
90 this->millimeters,
91 this->acceleration,
92 this->accelerate_until,
93 this->decelerate_after,
94 this->initial_rate,
95 this->entry_speed,
96 this->max_entry_speed,
97 this->is_ready,
98 this->locked,
99 this->is_ticking,
100 recalculate_flag ? 1 : 0,
101 nominal_length_flag ? 1 : 0,
102 total_move_ticks/STEP_TICKER_FREQUENCY
103 );
104 }
105
106
107 /* Calculates trapezoid parameters so that the entry- and exit-speed is compensated by the provided factors.
108 // The factors represent a factor of braking and must be in the range 0.0-1.0.
109 // +--------+ <- nominal_rate
110 // / \
111 // nominal_rate*entry_factor -> + \
112 // | + <- nominal_rate*exit_factor
113 // +-------------+
114 // time -->
115 */
116 void Block::calculate_trapezoid( float entryspeed, float exitspeed )
117 {
118 // if block is currently executing, don't touch anything!
119 if (is_ticking) return;
120
121 float initial_rate = this->nominal_rate * (entryspeed / this->nominal_speed); // steps/sec
122 float final_rate = this->nominal_rate * (exitspeed / this->nominal_speed);
123 //printf("Initial rate: %f, final_rate: %f\n", initial_rate, final_rate);
124 // How many steps ( can be fractions of steps, we need very precise values ) to accelerate and decelerate
125 // This is a simplification to get rid of rate_delta and get the steps/s² accel directly from the mm/s² accel
126 float acceleration_per_second = (this->acceleration * this->steps_event_count) / this->millimeters;
127
128 float maximum_possible_rate = sqrtf( ( this->steps_event_count * acceleration_per_second ) + ( ( powf(initial_rate, 2) + powf(final_rate, 2) ) / 2.0F ) );
129
130 //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);
131
132 // Now this is the maximum rate we'll achieve this move, either because
133 // it's the higher we can achieve, or because it's the higher we are
134 // allowed to achieve
135 this->maximum_rate = std::min(maximum_possible_rate, this->nominal_rate);
136
137 // Now figure out how long it takes to accelerate in seconds
138 float time_to_accelerate = ( this->maximum_rate - initial_rate ) / acceleration_per_second;
139
140 // Now figure out how long it takes to decelerate
141 float time_to_decelerate = ( final_rate - this->maximum_rate ) / -acceleration_per_second;
142
143 // Now we know how long it takes to accelerate and decelerate, but we must
144 // also know how long the entire move takes so we can figure out how long
145 // is the plateau if there is one
146 float plateau_time = 0;
147
148 // Only if there is actually a plateau ( we are limited by nominal_rate )
149 if(maximum_possible_rate > this->nominal_rate) {
150 // Figure out the acceleration and deceleration distances ( in steps )
151 float acceleration_distance = ( ( initial_rate + this->maximum_rate ) / 2.0F ) * time_to_accelerate;
152 float deceleration_distance = ( ( this->maximum_rate + final_rate ) / 2.0F ) * time_to_decelerate;
153
154 // Figure out the plateau steps
155 float plateau_distance = this->steps_event_count - acceleration_distance - deceleration_distance;
156
157 // Figure out the plateau time in seconds
158 plateau_time = plateau_distance / this->maximum_rate;
159 }
160
161 // Figure out how long the move takes total ( in seconds )
162 float total_move_time = time_to_accelerate + time_to_decelerate + plateau_time;
163 //puts "total move time: #{total_move_time}s time to accelerate: #{time_to_accelerate}, time to decelerate: #{time_to_decelerate}"
164
165 // We now have the full timing for acceleration, plateau and deceleration,
166 // yay \o/ Now this is very important these are in seconds, and we need to
167 // round them into ticks. This means instead of accelerating in 100.23
168 // ticks we'll accelerate in 100 ticks. Which means to reach the exact
169 // speed we want to reach, we must figure out a new/slightly different
170 // acceleration/deceleration to be sure we accelerate and decelerate at
171 // the exact rate we want
172
173 // First off round total time, acceleration time and deceleration time in ticks
174 uint32_t acceleration_ticks = floorf( time_to_accelerate * STEP_TICKER_FREQUENCY );
175 uint32_t deceleration_ticks = floorf( time_to_decelerate * STEP_TICKER_FREQUENCY );
176 uint32_t total_move_ticks = floorf( total_move_time * STEP_TICKER_FREQUENCY );
177
178 // Now deduce the plateau time for those new values expressed in tick
179 //uint32_t plateau_ticks = total_move_ticks - acceleration_ticks - deceleration_ticks;
180
181 // Now we figure out the acceleration value to reach EXACTLY maximum_rate(steps/s) in EXACTLY acceleration_ticks(ticks) amount of time in seconds
182 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
183 float deceleration_time = deceleration_ticks / STEP_TICKER_FREQUENCY;
184
185 float acceleration_in_steps = (acceleration_time > 0.0F ) ? ( this->maximum_rate - initial_rate ) / acceleration_time : 0;
186 float deceleration_in_steps = (deceleration_time > 0.0F ) ? ( this->maximum_rate - final_rate ) / deceleration_time : 0;
187
188 // we have a potential race condition here as we could get interrupted anywhere in the middle of this call, we need to lock
189 // the updates to the blocks to get around it
190 this->locked= true;
191 // Now figure out the two acceleration ramp change events in ticks
192 this->accelerate_until = acceleration_ticks;
193 this->decelerate_after = total_move_ticks - deceleration_ticks;
194
195 // 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
196 // steps/tick^2
197
198 this->acceleration_per_tick = acceleration_in_steps / STEP_TICKER_FREQUENCY_2;
199 this->deceleration_per_tick = deceleration_in_steps / STEP_TICKER_FREQUENCY_2;
200
201 // We now have everything we need for this block to call a Steppermotor->move method !!!!
202 // Theorically, if accel is done per tick, the speed curve should be perfect.
203 this->total_move_ticks = total_move_ticks;
204
205 //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}"
206
207 this->initial_rate = initial_rate;
208 this->exit_speed = exitspeed;
209
210 // prepare the block for stepticker
211 this->prepare();
212 this->locked= false;
213 }
214
215 // Calculates the maximum allowable speed at this point when you must be able to reach target_velocity using the
216 // acceleration within the allotted distance.
217 float Block::max_allowable_speed(float acceleration, float target_velocity, float distance)
218 {
219 return sqrtf(target_velocity * target_velocity - 2.0F * acceleration * distance);
220 }
221
222 // Called by Planner::recalculate() when scanning the plan from last to first entry.
223 float Block::reverse_pass(float exit_speed)
224 {
225 // If entry speed is already at the maximum entry speed, no need to recheck. Block is cruising.
226 // If not, block in state of acceleration or deceleration. Reset entry speed to maximum and
227 // check for maximum allowable speed reductions to ensure maximum possible planned speed.
228 if (this->entry_speed != this->max_entry_speed) {
229 // If nominal length true, max junction speed is guaranteed to be reached. Only compute
230 // for max allowable speed if block is decelerating and nominal length is false.
231 if ((!this->nominal_length_flag) && (this->max_entry_speed > exit_speed)) {
232 float max_entry_speed = max_allowable_speed(-this->acceleration, exit_speed, this->millimeters);
233
234 this->entry_speed = min(max_entry_speed, this->max_entry_speed);
235
236 return this->entry_speed;
237 } else
238 this->entry_speed = this->max_entry_speed;
239 }
240
241 return this->entry_speed;
242 }
243
244
245 // Called by Planner::recalculate() when scanning the plan from first to last entry.
246 // returns maximum exit speed of this block
247 float Block::forward_pass(float prev_max_exit_speed)
248 {
249 // If the previous block is an acceleration block, but it is not long enough to complete the
250 // full speed change within the block, we need to adjust the entry speed accordingly. Entry
251 // speeds have already been reset, maximized, and reverse planned by reverse planner.
252 // If nominal length is true, max junction speed is guaranteed to be reached. No need to recheck.
253
254 // TODO: find out if both of these checks are necessary
255 if (prev_max_exit_speed > nominal_speed)
256 prev_max_exit_speed = nominal_speed;
257 if (prev_max_exit_speed > max_entry_speed)
258 prev_max_exit_speed = max_entry_speed;
259
260 if (prev_max_exit_speed <= entry_speed) {
261 // accel limited
262 entry_speed = prev_max_exit_speed;
263 // since we're now acceleration or cruise limited
264 // we don't need to recalculate our entry speed anymore
265 recalculate_flag = false;
266 }
267 // else
268 // // decel limited, do nothing
269
270 return max_exit_speed();
271 }
272
273 float Block::max_exit_speed()
274 {
275 // if block is currently executing, return cached exit speed from calculate_trapezoid
276 // this ensures that a block following a currently executing block will have correct entry speed
277 if(is_ticking)
278 return this->exit_speed;
279
280 // if nominal_length_flag is asserted
281 // we are guaranteed to reach nominal speed regardless of entry speed
282 // thus, max exit will always be nominal
283 if (nominal_length_flag)
284 return nominal_speed;
285
286 // otherwise, we have to work out max exit speed based on entry and acceleration
287 float max = max_allowable_speed(-this->acceleration, this->entry_speed, this->millimeters);
288
289 return min(max, nominal_speed);
290 }
291
292 // prepare block for the step ticker, called everytime the block changes
293 // this is done during planning so does not delay tick generation and step ticker can simplh grab the next block during the interrupt
294 void Block::prepare()
295 {
296 float inv = 1.0F / this->steps_event_count;
297 for (uint8_t m = 0; m < k_max_actuators; m++) {
298 uint32_t steps = this->steps[m];
299 this->tick_info[m].steps_to_move = steps;
300 if(steps == 0) continue;
301
302 float aratio = inv * steps;
303 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
304 this->tick_info[m].counter = 0; // 2.30 fixed point
305 this->tick_info[m].step_count = 0;
306 this->tick_info[m].next_accel_event = this->total_move_ticks + 1;
307
308 float acceleration_change = 0;
309 if(this->accelerate_until != 0) { // If the next accel event is the end of accel
310 this->tick_info[m].next_accel_event = this->accelerate_until;
311 acceleration_change = this->acceleration_per_tick;
312
313 } else if(this->decelerate_after == 0 /*&& this->accelerate_until == 0*/) {
314 // we start off decelerating
315 acceleration_change = -this->deceleration_per_tick;
316
317 } else if(this->decelerate_after != this->total_move_ticks /*&& this->accelerate_until == 0*/) {
318 // If the next event is the start of decel ( don't set this if the next accel event is accel end )
319 this->tick_info[m].next_accel_event = this->decelerate_after;
320 }
321
322 // convert to fixed point after scaling
323 this->tick_info[m].acceleration_change= STEPTICKER_TOFP(acceleration_change * aratio);
324 this->tick_info[m].deceleration_change= -STEPTICKER_TOFP(this->deceleration_per_tick * aratio);
325 this->tick_info[m].plateau_rate= STEPTICKER_TOFP((this->maximum_rate * aratio) / STEP_TICKER_FREQUENCY);
326 }
327 }