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/>.
8 #include "libs/Module.h"
9 #include "libs/Kernel.h"
10 #include "libs/nuts_bolts.h"
18 #include "../communication/utils/Gcode.h"
20 // A block represents a movement, it's length for each stepper motor, and the corresponding acceleration curves.
21 // It's stacked on a queue, and that queue is then executed in order, to move the motors.
22 // Most of the accel math is also done in this class
23 // And GCode objects for use in on_gcode_execute are also help in here
26 clear_vector(this->steps
);
27 this->times_taken
= 0; // A block can be "taken" by any number of modules, and the next block is not moved to until all the modules have "released" it. This value serves as a tracker.
28 this->is_ready
= false;
29 this->initial_rate
= -1;
30 this->final_rate
= -1;
33 void Block::debug(Kernel
* kernel
){
34 kernel
->streams
->printf("%p: steps:%4d|%4d|%4d(max:%4d) nominal:r%10d/s%6.1f mm:%9.6f rdelta:%8f acc:%5d dec:%5d rates:%10d>%10d taken:%d ready:%d \r\n", this, this->steps
[0], this->steps
[1], this->steps
[2], this->steps_event_count
, this->nominal_rate
, this->nominal_speed
, this->millimeters
, this->rate_delta
, this->accelerate_until
, this->decelerate_after
, this->initial_rate
, this->final_rate
, this->times_taken
, this->is_ready
);
38 /* Calculates trapezoid parameters so that the entry- and exit-speed is compensated by the provided factors.
39 // The factors represent a factor of braking and must be in the range 0.0-1.0.
40 // +--------+ <- nominal_rate
42 // nominal_rate*entry_factor -> + \
43 // | + <- nominal_rate*exit_factor
47 void Block::calculate_trapezoid( double entryfactor
, double exitfactor
){
49 // The planner passes us factors, we need to transform them in rates
50 this->initial_rate
= ceil(this->nominal_rate
* entryfactor
); // (step/min)
51 this->final_rate
= ceil(this->nominal_rate
* exitfactor
); // (step/min)
53 // How many steps to accelerate and decelerate
54 double acceleration_per_minute
= this->rate_delta
* this->planner
->kernel
->stepper
->acceleration_ticks_per_second
* 60.0; // ( step/min^2)
55 int accelerate_steps
= ceil( this->estimate_acceleration_distance( this->initial_rate
, this->nominal_rate
, acceleration_per_minute
) );
56 int decelerate_steps
= floor( this->estimate_acceleration_distance( this->nominal_rate
, this->final_rate
, -acceleration_per_minute
) );
58 // Calculate the size of Plateau of Nominal Rate ( during which we don't accelerate nor decelerate, but just cruise )
59 int plateau_steps
= this->steps_event_count
-accelerate_steps
-decelerate_steps
;
61 // Is the Plateau of Nominal Rate smaller than nothing? That means no cruising, and we will
62 // have to use intersection_distance() to calculate when to abort acceleration and start braking
63 // in order to reach the final_rate exactly at the end of this block.
64 if (plateau_steps
< 0) {
65 accelerate_steps
= ceil(this->intersection_distance(this->initial_rate
, this->final_rate
, acceleration_per_minute
, this->steps_event_count
));
66 accelerate_steps
= max( accelerate_steps
, 0 ); // Check limits due to numerical round-off
67 accelerate_steps
= min( accelerate_steps
, int(this->steps_event_count
) );
70 this->accelerate_until
= accelerate_steps
;
71 this->decelerate_after
= accelerate_steps
+plateau_steps
;
75 // Calculates the distance (not time) it takes to accelerate from initial_rate to target_rate using the
76 // given acceleration:
77 double Block::estimate_acceleration_distance(double initialrate
, double targetrate
, double acceleration
) {
78 return( ((targetrate
*targetrate
)-(initialrate
*initialrate
))/(2L*acceleration
));
81 // This function gives you the point at which you must start braking (at the rate of -acceleration) if
82 // you started at speed initial_rate and accelerated until this point and want to end at the final_rate after
83 // a total travel of distance. This can be used to compute the intersection point between acceleration and
84 // deceleration in the cases where the trapezoid has no plateau (i.e. never reaches maximum speed)
86 /* + <- some maximum rate we don't care about
91 initial_rate -> +----+--+
94 intersection_distance distance */
95 double Block::intersection_distance(double initialrate
, double finalrate
, double acceleration
, double distance
) {
96 return((2*acceleration
*distance
-initialrate
*initialrate
+finalrate
*finalrate
)/(4*acceleration
));
99 // Calculates the maximum allowable speed at this point when you must be able to reach target_velocity using the
100 // acceleration within the allotted distance.
101 inline double max_allowable_speed(double acceleration
, double target_velocity
, double distance
) {
103 sqrt(target_velocity
*target_velocity
-2L*acceleration
*distance
) //Was acceleration*60*60*distance, in case this breaks, but here we prefer to use seconds instead of minutes
108 // Called by Planner::recalculate() when scanning the plan from last to first entry.
109 void Block::reverse_pass(Block
* next
, Block
* previous
){
112 // If entry speed is already at the maximum entry speed, no need to recheck. Block is cruising.
113 // If not, block in state of acceleration or deceleration. Reset entry speed to maximum and
114 // check for maximum allowable speed reductions to ensure maximum possible planned speed.
115 if (this->entry_speed
!= this->max_entry_speed
) {
117 // If nominal length true, max junction speed is guaranteed to be reached. Only compute
118 // for max allowable speed if block is decelerating and nominal length is false.
119 if ((!this->nominal_length_flag
) && (this->max_entry_speed
> next
->entry_speed
)) {
120 this->entry_speed
= min( this->max_entry_speed
, max_allowable_speed(-this->planner
->acceleration
,next
->entry_speed
,this->millimeters
));
122 this->entry_speed
= this->max_entry_speed
;
124 this->recalculate_flag
= true;
127 } // Skip last block. Already initialized and set for recalculation.
132 // Called by Planner::recalculate() when scanning the plan from first to last entry.
133 void Block::forward_pass(Block
* previous
, Block
* next
){
135 if(!previous
) { return; } // Begin planning after buffer_tail
137 // If the previous block is an acceleration block, but it is not long enough to complete the
138 // full speed change within the block, we need to adjust the entry speed accordingly. Entry
139 // speeds have already been reset, maximized, and reverse planned by reverse planner.
140 // If nominal length is true, max junction speed is guaranteed to be reached. No need to recheck.
141 if (!previous
->nominal_length_flag
) {
142 if (previous
->entry_speed
< this->entry_speed
) {
143 double entry_speed
= min( this->entry_speed
,
144 max_allowable_speed(-this->planner
->acceleration
,previous
->entry_speed
,previous
->millimeters
) );
146 // Check for junction speed change
147 if (this->entry_speed
!= entry_speed
) {
148 this->entry_speed
= entry_speed
;
149 this->recalculate_flag
= true;
157 // Gcodes are attached to their respective blocks so that on_gcode_execute can be called with it
158 void Block::append_gcode(Gcode
* gcode
){
160 Gcode new_gcode
= *gcode
;
161 this->gcodes
.push_back(new_gcode
);
165 // The attached gcodes are then poped and the on_gcode_execute event is called with them as a parameter
166 void Block::pop_and_execute_gcode(Kernel
* &kernel
){
167 Block
* block
= const_cast<Block
*>(this);
168 for(unsigned short index
=0; index
<block
->gcodes
.size(); index
++){
169 kernel
->call_event(ON_GCODE_EXECUTE
, &(block
->gcodes
[index
]));
173 // Signal the conveyor that this block is ready to be injected into the system
175 this->is_ready
= true;
176 this->conveyor
->new_block_added();
179 // Mark the block as taken by one more module
184 // Mark the block as no longer taken by one module, go to next block if this free's it
185 // This is one of the craziest bits in smoothie
186 void Block::release(){
188 // A block can be taken by several modules, we want to actually release it only when all modules have release()d it
190 if( this->times_taken
< 1 ){
192 // All modules are done with this block
193 // Call the on_block_end event so all modules can act accordingly
194 this->conveyor
->kernel
->call_event(ON_BLOCK_END
, this);
196 // Gcodes corresponding to the *following* blocks are stored in this block.
197 // We execute them all in order when this block is finished executing
198 this->pop_and_execute_gcode(this->conveyor
->kernel
);
200 // We would normally delete this block directly here, but we can't, because this is interrupt context, no crazy memory stuff here
201 // So instead we increment a counter, and it will be deleted in main loop context
202 Conveyor
* conveyor
= this->conveyor
;
203 if( conveyor
->queue
.size() > conveyor
->flush_blocks
){
204 conveyor
->flush_blocks
++;
207 // We don't look for the next block to execute if the conveyor is already doing that itself
208 if( conveyor
->looking_for_new_block
== false ){
210 // If there are still blocks to execute
211 if( conveyor
->queue
.size() > conveyor
->flush_blocks
){
212 Block
* candidate
= conveyor
->queue
.get_ref(conveyor
->flush_blocks
);
214 // We only execute blocks that are ready ( their math is done )
215 if( candidate
->is_ready
){
217 // Execute this candidate
218 conveyor
->current_block
= candidate
;
219 conveyor
->kernel
->call_event(ON_BLOCK_BEGIN
, conveyor
->current_block
);
221 // If no module took this block, release it ourselves, as nothing else will do it otherwise
222 if( conveyor
->current_block
->times_taken
< 1 ){
223 conveyor
->current_block
->times_taken
= 1;
224 conveyor
->current_block
->release();
227 conveyor
->current_block
= NULL
;
230 conveyor
->current_block
= NULL
;