1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
|
/****************************************************************************
*
* Copyright (c) 2013, 2014 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/**
* @file mc_att_control_main.cpp
* Multicopter attitude controller.
*
* @author Tobias Naegeli <naegelit@student.ethz.ch>
* @author Lorenz Meier <lm@inf.ethz.ch>
* @author Anton Babushkin <anton.babushkin@me.com>
*
* The controller has two loops: P loop for angular error and PD loop for angular rate error.
* Desired rotation calculated keeping in mind that yaw response is normally slower than roll/pitch.
* For small deviations controller rotates copter to have shortest path of thrust vector and independently rotates around yaw,
* so actual rotation axis is not constant. For large deviations controller rotates copter around fixed axis.
* These two approaches fused seamlessly with weight depending on angular error.
* When thrust vector directed near-horizontally (e.g. roll ~= PI/2) yaw setpoint ignored because of singularity.
* Controller doesn't use Euler angles for work, they generated only for more human-friendly control and logging.
* If rotation matrix setpoint is invalid it will be generated from Euler angles for compatibility with old position controllers.
*/
#include <nuttx/config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <math.h>
#include <poll.h>
#include <drivers/drv_hrt.h>
#include <arch/board/board.h>
#include <uORB/uORB.h>
#include <uORB/topics/vehicle_attitude_setpoint.h>
#include <uORB/topics/manual_control_setpoint.h>
#include <uORB/topics/actuator_controls.h>
#include <uORB/topics/actuator_controls_virtual_fw.h>
#include <uORB/topics/actuator_controls_virtual_mc.h>
#include <uORB/topics/vehicle_rates_setpoint.h>
#include <uORB/topics/fw_virtual_rates_setpoint.h>
#include <uORB/topics/mc_virtual_rates_setpoint.h>
#include <uORB/topics/vehicle_attitude.h>
#include <uORB/topics/vehicle_control_mode.h>
#include <uORB/topics/vehicle_status.h>
#include <uORB/topics/actuator_armed.h>
#include <uORB/topics/parameter_update.h>
#include <systemlib/param/param.h>
#include <systemlib/err.h>
#include <systemlib/perf_counter.h>
#include <systemlib/systemlib.h>
#include <systemlib/circuit_breaker.h>
#include <lib/mathlib/mathlib.h>
#include <lib/geo/geo.h>
/**
* Multicopter attitude control app start / stop handling function
*
* @ingroup apps
*/
extern "C" __EXPORT int mc_att_control_main(int argc, char *argv[]);
#define YAW_DEADZONE 0.05f
#define MIN_TAKEOFF_THRUST 0.2f
#define RATES_I_LIMIT 0.3f
class MulticopterAttitudeControl
{
public:
/**
* Constructor
*/
MulticopterAttitudeControl();
/**
* Destructor, also kills the main task
*/
~MulticopterAttitudeControl();
/**
* Start the multicopter attitude control task.
*
* @return OK on success.
*/
int start();
private:
bool _task_should_exit; /**< if true, task_main() should exit */
int _control_task; /**< task handle */
int _v_att_sub; /**< vehicle attitude subscription */
int _v_att_sp_sub; /**< vehicle attitude setpoint subscription */
int _v_rates_sp_sub; /**< vehicle rates setpoint subscription */
int _v_control_mode_sub; /**< vehicle control mode subscription */
int _params_sub; /**< parameter updates subscription */
int _manual_control_sp_sub; /**< manual control setpoint subscription */
int _armed_sub; /**< arming status subscription */
int _vehicle_status_sub; /**< vehicle status subscription */
orb_advert_t _att_sp_pub; /**< attitude setpoint publication */
orb_advert_t _v_rates_sp_pub; /**< rate setpoint publication */
orb_advert_t _actuators_0_pub; /**< attitude actuator controls publication */
orb_id_t _rates_sp_id; /**< pointer to correct rates setpoint uORB metadata structure */
orb_id_t _actuators_id; /**< pointer to correct actuator controls0 uORB metadata structure */
bool _actuators_0_circuit_breaker_enabled; /**< circuit breaker to suppress output */
struct vehicle_attitude_s _v_att; /**< vehicle attitude */
struct vehicle_attitude_setpoint_s _v_att_sp; /**< vehicle attitude setpoint */
struct vehicle_rates_setpoint_s _v_rates_sp; /**< vehicle rates setpoint */
struct manual_control_setpoint_s _manual_control_sp; /**< manual control setpoint */
struct vehicle_control_mode_s _v_control_mode; /**< vehicle control mode */
struct actuator_controls_s _actuators; /**< actuator controls */
struct actuator_armed_s _armed; /**< actuator arming status */
struct vehicle_status_s _vehicle_status; /**< vehicle status */
perf_counter_t _loop_perf; /**< loop performance counter */
perf_counter_t _controller_latency_perf;
math::Vector<3> _rates_prev; /**< angular rates on previous step */
math::Vector<3> _rates_sp; /**< angular rates setpoint */
math::Vector<3> _rates_int; /**< angular rates integral error */
float _thrust_sp; /**< thrust setpoint */
math::Vector<3> _att_control; /**< attitude control vector */
math::Matrix<3, 3> _I; /**< identity matrix */
bool _reset_yaw_sp; /**< reset yaw setpoint flag */
struct {
param_t roll_p;
param_t roll_rate_p;
param_t roll_rate_i;
param_t roll_rate_d;
param_t pitch_p;
param_t pitch_rate_p;
param_t pitch_rate_i;
param_t pitch_rate_d;
param_t yaw_p;
param_t yaw_rate_p;
param_t yaw_rate_i;
param_t yaw_rate_d;
param_t yaw_ff;
param_t yaw_rate_max;
param_t man_roll_max;
param_t man_pitch_max;
param_t man_yaw_max;
param_t acro_roll_max;
param_t acro_pitch_max;
param_t acro_yaw_max;
} _params_handles; /**< handles for interesting parameters */
struct {
math::Vector<3> att_p; /**< P gain for angular error */
math::Vector<3> rate_p; /**< P gain for angular rate error */
math::Vector<3> rate_i; /**< I gain for angular rate error */
math::Vector<3> rate_d; /**< D gain for angular rate error */
float yaw_ff; /**< yaw control feed-forward */
float yaw_rate_max; /**< max yaw rate */
float man_roll_max;
float man_pitch_max;
float man_yaw_max;
math::Vector<3> acro_rate_max; /**< max attitude rates in acro mode */
} _params;
/**
* Update our local parameter cache.
*/
int parameters_update();
/**
* Check for parameter update and handle it.
*/
void parameter_update_poll();
/**
* Check for changes in vehicle control mode.
*/
void vehicle_control_mode_poll();
/**
* Check for changes in manual inputs.
*/
void vehicle_manual_poll();
/**
* Check for attitude setpoint updates.
*/
void vehicle_attitude_setpoint_poll();
/**
* Check for rates setpoint updates.
*/
void vehicle_rates_setpoint_poll();
/**
* Check for arming status updates.
*/
void arming_status_poll();
/**
* Attitude controller.
*/
void control_attitude(float dt);
/**
* Attitude rates controller.
*/
void control_attitude_rates(float dt);
/**
* Check for vehicle status updates.
*/
void vehicle_status_poll();
/**
* Shim for calling task_main from task_create.
*/
static void task_main_trampoline(int argc, char *argv[]);
/**
* Main attitude control task.
*/
void task_main();
};
namespace mc_att_control
{
/* oddly, ERROR is not defined for c++ */
#ifdef ERROR
# undef ERROR
#endif
static const int ERROR = -1;
MulticopterAttitudeControl *g_control;
}
MulticopterAttitudeControl::MulticopterAttitudeControl() :
_task_should_exit(false),
_control_task(-1),
/* subscriptions */
_v_att_sub(-1),
_v_att_sp_sub(-1),
_v_control_mode_sub(-1),
_params_sub(-1),
_manual_control_sp_sub(-1),
_armed_sub(-1),
_vehicle_status_sub(-1),
/* publications */
_att_sp_pub(-1),
_v_rates_sp_pub(-1),
_actuators_0_pub(-1),
_rates_sp_id(0),
_actuators_id(0),
_actuators_0_circuit_breaker_enabled(false),
/* performance counters */
_loop_perf(perf_alloc(PC_ELAPSED, "mc_att_control")),
_controller_latency_perf(perf_alloc_once(PC_ELAPSED, "ctrl_latency"))
{
memset(&_v_att, 0, sizeof(_v_att));
memset(&_v_att_sp, 0, sizeof(_v_att_sp));
memset(&_v_rates_sp, 0, sizeof(_v_rates_sp));
memset(&_manual_control_sp, 0, sizeof(_manual_control_sp));
memset(&_v_control_mode, 0, sizeof(_v_control_mode));
memset(&_actuators, 0, sizeof(_actuators));
memset(&_armed, 0, sizeof(_armed));
memset(&_vehicle_status, 0, sizeof(_vehicle_status));
_vehicle_status.is_rotary_wing = true;
_params.att_p.zero();
_params.rate_p.zero();
_params.rate_i.zero();
_params.rate_d.zero();
_params.yaw_ff = 0.0f;
_params.yaw_rate_max = 0.0f;
_params.man_roll_max = 0.0f;
_params.man_pitch_max = 0.0f;
_params.man_yaw_max = 0.0f;
_params.acro_rate_max.zero();
_rates_prev.zero();
_rates_sp.zero();
_rates_int.zero();
_thrust_sp = 0.0f;
_att_control.zero();
_I.identity();
_params_handles.roll_p = param_find("MC_ROLL_P");
_params_handles.roll_rate_p = param_find("MC_ROLLRATE_P");
_params_handles.roll_rate_i = param_find("MC_ROLLRATE_I");
_params_handles.roll_rate_d = param_find("MC_ROLLRATE_D");
_params_handles.pitch_p = param_find("MC_PITCH_P");
_params_handles.pitch_rate_p = param_find("MC_PITCHRATE_P");
_params_handles.pitch_rate_i = param_find("MC_PITCHRATE_I");
_params_handles.pitch_rate_d = param_find("MC_PITCHRATE_D");
_params_handles.yaw_p = param_find("MC_YAW_P");
_params_handles.yaw_rate_p = param_find("MC_YAWRATE_P");
_params_handles.yaw_rate_i = param_find("MC_YAWRATE_I");
_params_handles.yaw_rate_d = param_find("MC_YAWRATE_D");
_params_handles.yaw_ff = param_find("MC_YAW_FF");
_params_handles.yaw_rate_max = param_find("MC_YAWRATE_MAX");
_params_handles.man_roll_max = param_find("MC_MAN_R_MAX");
_params_handles.man_pitch_max = param_find("MC_MAN_P_MAX");
_params_handles.man_yaw_max = param_find("MC_MAN_Y_MAX");
_params_handles.acro_roll_max = param_find("MC_ACRO_R_MAX");
_params_handles.acro_pitch_max = param_find("MC_ACRO_P_MAX");
_params_handles.acro_yaw_max = param_find("MC_ACRO_Y_MAX");
/* fetch initial parameter values */
parameters_update();
}
MulticopterAttitudeControl::~MulticopterAttitudeControl()
{
if (_control_task != -1) {
/* task wakes up every 100ms or so at the longest */
_task_should_exit = true;
/* wait for a second for the task to quit at our request */
unsigned i = 0;
do {
/* wait 20ms */
usleep(20000);
/* if we have given up, kill it */
if (++i > 50) {
task_delete(_control_task);
break;
}
} while (_control_task != -1);
}
mc_att_control::g_control = nullptr;
}
int
MulticopterAttitudeControl::parameters_update()
{
float v;
/* roll gains */
param_get(_params_handles.roll_p, &v);
_params.att_p(0) = v;
param_get(_params_handles.roll_rate_p, &v);
_params.rate_p(0) = v;
param_get(_params_handles.roll_rate_i, &v);
_params.rate_i(0) = v;
param_get(_params_handles.roll_rate_d, &v);
_params.rate_d(0) = v;
/* pitch gains */
param_get(_params_handles.pitch_p, &v);
_params.att_p(1) = v;
param_get(_params_handles.pitch_rate_p, &v);
_params.rate_p(1) = v;
param_get(_params_handles.pitch_rate_i, &v);
_params.rate_i(1) = v;
param_get(_params_handles.pitch_rate_d, &v);
_params.rate_d(1) = v;
/* yaw gains */
param_get(_params_handles.yaw_p, &v);
_params.att_p(2) = v;
param_get(_params_handles.yaw_rate_p, &v);
_params.rate_p(2) = v;
param_get(_params_handles.yaw_rate_i, &v);
_params.rate_i(2) = v;
param_get(_params_handles.yaw_rate_d, &v);
_params.rate_d(2) = v;
param_get(_params_handles.yaw_ff, &_params.yaw_ff);
param_get(_params_handles.yaw_rate_max, &_params.yaw_rate_max);
_params.yaw_rate_max = math::radians(_params.yaw_rate_max);
/* manual control scale */
param_get(_params_handles.man_roll_max, &_params.man_roll_max);
param_get(_params_handles.man_pitch_max, &_params.man_pitch_max);
param_get(_params_handles.man_yaw_max, &_params.man_yaw_max);
_params.man_roll_max = math::radians(_params.man_roll_max);
_params.man_pitch_max = math::radians(_params.man_pitch_max);
_params.man_yaw_max = math::radians(_params.man_yaw_max);
/* acro control scale */
param_get(_params_handles.acro_roll_max, &v);
_params.acro_rate_max(0) = math::radians(v);
param_get(_params_handles.acro_pitch_max, &v);
_params.acro_rate_max(1) = math::radians(v);
param_get(_params_handles.acro_yaw_max, &v);
_params.acro_rate_max(2) = math::radians(v);
_actuators_0_circuit_breaker_enabled = circuit_breaker_enabled("CBRK_RATE_CTRL", CBRK_RATE_CTRL_KEY);
return OK;
}
void
MulticopterAttitudeControl::parameter_update_poll()
{
bool updated;
/* Check if parameters have changed */
orb_check(_params_sub, &updated);
if (updated) {
struct parameter_update_s param_update;
orb_copy(ORB_ID(parameter_update), _params_sub, ¶m_update);
parameters_update();
}
}
void
MulticopterAttitudeControl::vehicle_control_mode_poll()
{
bool updated;
/* Check if vehicle control mode has changed */
orb_check(_v_control_mode_sub, &updated);
if (updated) {
orb_copy(ORB_ID(vehicle_control_mode), _v_control_mode_sub, &_v_control_mode);
}
}
void
MulticopterAttitudeControl::vehicle_manual_poll()
{
bool updated;
/* get pilots inputs */
orb_check(_manual_control_sp_sub, &updated);
if (updated) {
orb_copy(ORB_ID(manual_control_setpoint), _manual_control_sp_sub, &_manual_control_sp);
}
}
void
MulticopterAttitudeControl::vehicle_attitude_setpoint_poll()
{
/* check if there is a new setpoint */
bool updated;
orb_check(_v_att_sp_sub, &updated);
if (updated) {
orb_copy(ORB_ID(vehicle_attitude_setpoint), _v_att_sp_sub, &_v_att_sp);
}
}
void
MulticopterAttitudeControl::vehicle_rates_setpoint_poll()
{
/* check if there is a new setpoint */
bool updated;
orb_check(_v_rates_sp_sub, &updated);
if (updated) {
orb_copy(ORB_ID(vehicle_rates_setpoint), _v_rates_sp_sub, &_v_rates_sp);
}
}
void
MulticopterAttitudeControl::arming_status_poll()
{
/* check if there is a new setpoint */
bool updated;
orb_check(_armed_sub, &updated);
if (updated) {
orb_copy(ORB_ID(actuator_armed), _armed_sub, &_armed);
}
}
void
MulticopterAttitudeControl::vehicle_status_poll()
{
/* check if there is new status information */
bool vehicle_status_updated;
orb_check(_vehicle_status_sub, &vehicle_status_updated);
if (vehicle_status_updated) {
orb_copy(ORB_ID(vehicle_status), _vehicle_status_sub, &_vehicle_status);
/* set correct uORB ID, depending on if vehicle is VTOL or not */
if (!_rates_sp_id) {
if (_vehicle_status.is_vtol) {
_rates_sp_id = ORB_ID(mc_virtual_rates_setpoint);
_actuators_id = ORB_ID(actuator_controls_virtual_mc);
} else {
_rates_sp_id = ORB_ID(vehicle_rates_setpoint);
_actuators_id = ORB_ID(actuator_controls_0);
}
}
}
}
/*
* Attitude controller.
* Input: 'manual_control_setpoint' and 'vehicle_attitude_setpoint' topics (depending on mode)
* Output: '_rates_sp' vector, '_thrust_sp', 'vehicle_attitude_setpoint' topic (for manual modes)
*/
void
MulticopterAttitudeControl::control_attitude(float dt)
{
float yaw_sp_move_rate = 0.0f;
bool publish_att_sp = false;
if (_v_control_mode.flag_control_manual_enabled) {
/* manual input, set or modify attitude setpoint */
if (_v_control_mode.flag_control_velocity_enabled || _v_control_mode.flag_control_climb_rate_enabled) {
/* in assisted modes poll 'vehicle_attitude_setpoint' topic and modify it */
vehicle_attitude_setpoint_poll();
}
if (!_v_control_mode.flag_control_climb_rate_enabled) {
/* pass throttle directly if not in altitude stabilized mode */
_v_att_sp.thrust = _manual_control_sp.z;
publish_att_sp = true;
}
if (!_armed.armed) {
/* reset yaw setpoint when disarmed */
_reset_yaw_sp = true;
}
/* move yaw setpoint in all modes */
if (_v_att_sp.thrust < 0.1f) {
// TODO
//if (_status.condition_landed) {
/* reset yaw setpoint if on ground */
// reset_yaw_sp = true;
//}
} else {
/* move yaw setpoint */
yaw_sp_move_rate = _manual_control_sp.r * _params.man_yaw_max;
_v_att_sp.yaw_body = _wrap_pi(_v_att_sp.yaw_body + yaw_sp_move_rate * dt);
float yaw_offs_max = _params.man_yaw_max / _params.att_p(2);
float yaw_offs = _wrap_pi(_v_att_sp.yaw_body - _v_att.yaw);
if (yaw_offs < - yaw_offs_max) {
_v_att_sp.yaw_body = _wrap_pi(_v_att.yaw - yaw_offs_max);
} else if (yaw_offs > yaw_offs_max) {
_v_att_sp.yaw_body = _wrap_pi(_v_att.yaw + yaw_offs_max);
}
_v_att_sp.R_valid = false;
publish_att_sp = true;
}
/* reset yaw setpint to current position if needed */
if (_reset_yaw_sp) {
_reset_yaw_sp = false;
_v_att_sp.yaw_body = _v_att.yaw;
_v_att_sp.R_valid = false;
publish_att_sp = true;
}
if (!_v_control_mode.flag_control_velocity_enabled) {
/* update attitude setpoint if not in position control mode */
_v_att_sp.roll_body = _manual_control_sp.y * _params.man_roll_max;
_v_att_sp.pitch_body = -_manual_control_sp.x * _params.man_pitch_max;
_v_att_sp.R_valid = false;
publish_att_sp = true;
}
} else {
/* in non-manual mode use 'vehicle_attitude_setpoint' topic */
vehicle_attitude_setpoint_poll();
/* reset yaw setpoint after non-manual control mode */
_reset_yaw_sp = true;
}
_thrust_sp = _v_att_sp.thrust;
/* construct attitude setpoint rotation matrix */
math::Matrix<3, 3> R_sp;
if (_v_att_sp.R_valid) {
/* rotation matrix in _att_sp is valid, use it */
R_sp.set(&_v_att_sp.R_body[0]);
} else {
/* rotation matrix in _att_sp is not valid, use euler angles instead */
R_sp.from_euler(_v_att_sp.roll_body, _v_att_sp.pitch_body, _v_att_sp.yaw_body);
/* copy rotation matrix back to setpoint struct */
memcpy(&_v_att_sp.R_body[0], &R_sp.data[0], sizeof(_v_att_sp.R_body));
_v_att_sp.R_valid = true;
}
/* publish the attitude setpoint if needed */
if (publish_att_sp && _vehicle_status.is_rotary_wing) {
_v_att_sp.timestamp = hrt_absolute_time();
if (_att_sp_pub > 0) {
orb_publish(ORB_ID(vehicle_attitude_setpoint), _att_sp_pub, &_v_att_sp);
} else {
_att_sp_pub = orb_advertise(ORB_ID(vehicle_attitude_setpoint), &_v_att_sp);
}
}
/* rotation matrix for current state */
math::Matrix<3, 3> R;
R.set(_v_att.R);
/* all input data is ready, run controller itself */
/* try to move thrust vector shortest way, because yaw response is slower than roll/pitch */
math::Vector<3> R_z(R(0, 2), R(1, 2), R(2, 2));
math::Vector<3> R_sp_z(R_sp(0, 2), R_sp(1, 2), R_sp(2, 2));
/* axis and sin(angle) of desired rotation */
math::Vector<3> e_R = R.transposed() * (R_z % R_sp_z);
/* calculate angle error */
float e_R_z_sin = e_R.length();
float e_R_z_cos = R_z * R_sp_z;
/* calculate weight for yaw control */
float yaw_w = R_sp(2, 2) * R_sp(2, 2);
/* calculate rotation matrix after roll/pitch only rotation */
math::Matrix<3, 3> R_rp;
if (e_R_z_sin > 0.0f) {
/* get axis-angle representation */
float e_R_z_angle = atan2f(e_R_z_sin, e_R_z_cos);
math::Vector<3> e_R_z_axis = e_R / e_R_z_sin;
e_R = e_R_z_axis * e_R_z_angle;
/* cross product matrix for e_R_axis */
math::Matrix<3, 3> e_R_cp;
e_R_cp.zero();
e_R_cp(0, 1) = -e_R_z_axis(2);
e_R_cp(0, 2) = e_R_z_axis(1);
e_R_cp(1, 0) = e_R_z_axis(2);
e_R_cp(1, 2) = -e_R_z_axis(0);
e_R_cp(2, 0) = -e_R_z_axis(1);
e_R_cp(2, 1) = e_R_z_axis(0);
/* rotation matrix for roll/pitch only rotation */
R_rp = R * (_I + e_R_cp * e_R_z_sin + e_R_cp * e_R_cp * (1.0f - e_R_z_cos));
} else {
/* zero roll/pitch rotation */
R_rp = R;
}
/* R_rp and R_sp has the same Z axis, calculate yaw error */
math::Vector<3> R_sp_x(R_sp(0, 0), R_sp(1, 0), R_sp(2, 0));
math::Vector<3> R_rp_x(R_rp(0, 0), R_rp(1, 0), R_rp(2, 0));
e_R(2) = atan2f((R_rp_x % R_sp_x) * R_sp_z, R_rp_x * R_sp_x) * yaw_w;
if (e_R_z_cos < 0.0f) {
/* for large thrust vector rotations use another rotation method:
* calculate angle and axis for R -> R_sp rotation directly */
math::Quaternion q;
q.from_dcm(R.transposed() * R_sp);
math::Vector<3> e_R_d = q.imag();
e_R_d.normalize();
e_R_d *= 2.0f * atan2f(e_R_d.length(), q(0));
/* use fusion of Z axis based rotation and direct rotation */
float direct_w = e_R_z_cos * e_R_z_cos * yaw_w;
e_R = e_R * (1.0f - direct_w) + e_R_d * direct_w;
}
/* calculate angular rates setpoint */
_rates_sp = _params.att_p.emult(e_R);
/* limit yaw rate */
_rates_sp(2) = math::constrain(_rates_sp(2), -_params.yaw_rate_max, _params.yaw_rate_max);
/* feed forward yaw setpoint rate */
_rates_sp(2) += yaw_sp_move_rate * yaw_w * _params.yaw_ff;
}
/*
* Attitude rates controller.
* Input: '_rates_sp' vector, '_thrust_sp'
* Output: '_att_control' vector
*/
void
MulticopterAttitudeControl::control_attitude_rates(float dt)
{
/* reset integral if disarmed */
if (!_armed.armed || !_vehicle_status.is_rotary_wing) {
_rates_int.zero();
}
/* current body angular rates */
math::Vector<3> rates;
rates(0) = _v_att.rollspeed;
rates(1) = _v_att.pitchspeed;
rates(2) = _v_att.yawspeed;
/* angular rates error */
math::Vector<3> rates_err = _rates_sp - rates;
_att_control = _params.rate_p.emult(rates_err) + _params.rate_d.emult(_rates_prev - rates) / dt + _rates_int;
_rates_prev = rates;
/* update integral only if not saturated on low limit */
if (_thrust_sp > MIN_TAKEOFF_THRUST) {
for (int i = 0; i < 3; i++) {
if (fabsf(_att_control(i)) < _thrust_sp) {
float rate_i = _rates_int(i) + _params.rate_i(i) * rates_err(i) * dt;
if (isfinite(rate_i) && rate_i > -RATES_I_LIMIT && rate_i < RATES_I_LIMIT &&
_att_control(i) > -RATES_I_LIMIT && _att_control(i) < RATES_I_LIMIT) {
_rates_int(i) = rate_i;
}
}
}
}
}
void
MulticopterAttitudeControl::task_main_trampoline(int argc, char *argv[])
{
mc_att_control::g_control->task_main();
}
void
MulticopterAttitudeControl::task_main()
{
/*
* do subscriptions
*/
_v_att_sp_sub = orb_subscribe(ORB_ID(vehicle_attitude_setpoint));
_v_rates_sp_sub = orb_subscribe(ORB_ID(vehicle_rates_setpoint));
_v_att_sub = orb_subscribe(ORB_ID(vehicle_attitude));
_v_control_mode_sub = orb_subscribe(ORB_ID(vehicle_control_mode));
_params_sub = orb_subscribe(ORB_ID(parameter_update));
_manual_control_sp_sub = orb_subscribe(ORB_ID(manual_control_setpoint));
_armed_sub = orb_subscribe(ORB_ID(actuator_armed));
_vehicle_status_sub = orb_subscribe(ORB_ID(vehicle_status));
/* initialize parameters cache */
parameters_update();
/* wakeup source: vehicle attitude */
struct pollfd fds[1];
fds[0].fd = _v_att_sub;
fds[0].events = POLLIN;
while (!_task_should_exit) {
/* wait for up to 100ms for data */
int pret = poll(&fds[0], (sizeof(fds) / sizeof(fds[0])), 100);
/* timed out - periodic check for _task_should_exit */
if (pret == 0)
continue;
/* this is undesirable but not much we can do - might want to flag unhappy status */
if (pret < 0) {
warn("poll error %d, %d", pret, errno);
/* sleep a bit before next try */
usleep(100000);
continue;
}
perf_begin(_loop_perf);
/* run controller on attitude changes */
if (fds[0].revents & POLLIN) {
static uint64_t last_run = 0;
float dt = (hrt_absolute_time() - last_run) / 1000000.0f;
last_run = hrt_absolute_time();
/* guard against too small (< 2ms) and too large (> 20ms) dt's */
if (dt < 0.002f) {
dt = 0.002f;
} else if (dt > 0.02f) {
dt = 0.02f;
}
/* copy attitude topic */
orb_copy(ORB_ID(vehicle_attitude), _v_att_sub, &_v_att);
/* check for updates in other topics */
parameter_update_poll();
vehicle_control_mode_poll();
arming_status_poll();
vehicle_manual_poll();
vehicle_status_poll();
if (_v_control_mode.flag_control_attitude_enabled) {
control_attitude(dt);
/* publish attitude rates setpoint */
_v_rates_sp.roll = _rates_sp(0);
_v_rates_sp.pitch = _rates_sp(1);
_v_rates_sp.yaw = _rates_sp(2);
_v_rates_sp.thrust = _thrust_sp;
_v_rates_sp.timestamp = hrt_absolute_time();
if (_v_rates_sp_pub > 0) {
orb_publish(_rates_sp_id, _v_rates_sp_pub, &_v_rates_sp);
} else if (_rates_sp_id) {
_v_rates_sp_pub = orb_advertise(_rates_sp_id, &_v_rates_sp);
}
} else {
/* attitude controller disabled, poll rates setpoint topic */
if (_v_control_mode.flag_control_manual_enabled) {
/* manual rates control - ACRO mode */
_rates_sp = math::Vector<3>(_manual_control_sp.y, -_manual_control_sp.x, _manual_control_sp.r).emult(_params.acro_rate_max);
_thrust_sp = _manual_control_sp.z;
/* reset yaw setpoint after ACRO */
_reset_yaw_sp = true;
/* publish attitude rates setpoint */
_v_rates_sp.roll = _rates_sp(0);
_v_rates_sp.pitch = _rates_sp(1);
_v_rates_sp.yaw = _rates_sp(2);
_v_rates_sp.thrust = _thrust_sp;
_v_rates_sp.timestamp = hrt_absolute_time();
if (_v_rates_sp_pub > 0) {
orb_publish(_rates_sp_id, _v_rates_sp_pub, &_v_rates_sp);
} else if (_rates_sp_id) {
_v_rates_sp_pub = orb_advertise(_rates_sp_id, &_v_rates_sp);
}
} else {
/* attitude controller disabled, poll rates setpoint topic */
vehicle_rates_setpoint_poll();
_rates_sp(0) = _v_rates_sp.roll;
_rates_sp(1) = _v_rates_sp.pitch;
_rates_sp(2) = _v_rates_sp.yaw;
_thrust_sp = _v_rates_sp.thrust;
}
}
if (_v_control_mode.flag_control_rates_enabled) {
control_attitude_rates(dt);
/* publish actuator controls */
_actuators.control[0] = (isfinite(_att_control(0))) ? _att_control(0) : 0.0f;
_actuators.control[1] = (isfinite(_att_control(1))) ? _att_control(1) : 0.0f;
_actuators.control[2] = (isfinite(_att_control(2))) ? _att_control(2) : 0.0f;
_actuators.control[3] = (isfinite(_thrust_sp)) ? _thrust_sp : 0.0f;
_actuators.timestamp = hrt_absolute_time();
_actuators.timestamp_sample = _v_att.timestamp;
if (!_actuators_0_circuit_breaker_enabled) {
if (_actuators_0_pub > 0) {
orb_publish(_actuators_id, _actuators_0_pub, &_actuators);
perf_end(_controller_latency_perf);
} else if (_actuators_id) {
_actuators_0_pub = orb_advertise(_actuators_id, &_actuators);
}
}
}
}
perf_end(_loop_perf);
}
warnx("exit");
_control_task = -1;
_exit(0);
}
int
MulticopterAttitudeControl::start()
{
ASSERT(_control_task == -1);
/* start the task */
_control_task = task_spawn_cmd("mc_att_control",
SCHED_DEFAULT,
SCHED_PRIORITY_MAX - 5,
2000,
(main_t)&MulticopterAttitudeControl::task_main_trampoline,
nullptr);
if (_control_task < 0) {
warn("task start failed");
return -errno;
}
return OK;
}
int mc_att_control_main(int argc, char *argv[])
{
if (argc < 1)
errx(1, "usage: mc_att_control {start|stop|status}");
if (!strcmp(argv[1], "start")) {
if (mc_att_control::g_control != nullptr)
errx(1, "already running");
mc_att_control::g_control = new MulticopterAttitudeControl;
if (mc_att_control::g_control == nullptr)
errx(1, "alloc failed");
if (OK != mc_att_control::g_control->start()) {
delete mc_att_control::g_control;
mc_att_control::g_control = nullptr;
err(1, "start failed");
}
exit(0);
}
if (!strcmp(argv[1], "stop")) {
if (mc_att_control::g_control == nullptr)
errx(1, "not running");
delete mc_att_control::g_control;
mc_att_control::g_control = nullptr;
exit(0);
}
if (!strcmp(argv[1], "status")) {
if (mc_att_control::g_control) {
errx(0, "running");
} else {
errx(1, "not running");
}
}
warnx("unrecognized command");
return 1;
}
|