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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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// + Copyright (c) 04.2007 Holger Buss
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// + Nur für den privaten Gebrauch
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// + www.MikroKopter.com
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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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// + Es gilt für das gesamte Projekt (Hardware, Software, Binärfiles, Sourcecode und Dokumentation),
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// + dass eine Nutzung (auch auszugsweise) nur für den privaten (nicht-kommerziellen) Gebrauch zulässig ist.
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// + Sollten direkte oder indirekte kommerzielle Absichten verfolgt werden, ist mit uns (info@mikrokopter.de) Kontakt
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// + bzgl. der Nutzungsbedingungen aufzunehmen.
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// + Eine kommerzielle Nutzung ist z.B.Verkauf von MikroKoptern, Bestückung und Verkauf von Platinen oder Bausätzen,
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// + Verkauf von Luftbildaufnahmen, usw.
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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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// + Werden Teile des Quellcodes (mit oder ohne Modifikation) weiterverwendet oder veröffentlicht,
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// + unterliegen sie auch diesen Nutzungsbedingungen und diese Nutzungsbedingungen incl. Copyright müssen dann beiliegen
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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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// + Sollte die Software (auch auszugesweise) oder sonstige Informationen des MikroKopter-Projekts
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// + auf anderen Webseiten oder sonstigen Medien veröffentlicht werden, muss unsere Webseite "http://www.mikrokopter.de"
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// + eindeutig als Ursprung verlinkt werden
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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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// + Keine Gewähr auf Fehlerfreiheit, Vollständigkeit oder Funktion
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// + Benutzung auf eigene Gefahr
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// + Wir übernehmen keinerlei Haftung für direkte oder indirekte Personen- oder Sachschäden
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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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// + Die Portierung der Software (oder Teile davon) auf andere Systeme (ausser der Hardware von www.mikrokopter.de) ist nur
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// + mit unserer Zustimmung zulässig
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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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// + Die Funktion printf_P() unterliegt ihrer eigenen Lizenz und ist hiervon nicht betroffen
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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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// + Redistributions of source code (with or without modifications) must retain the above copyright notice,
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// + this list of conditions and the following disclaimer.
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// +   * Neither the name of the copyright holders nor the names of contributors may be used to endorse or promote products derived
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// +     from this software without specific prior written permission.
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// +   * The use of this project (hardware, software, binary files, sources and documentation) is only permittet
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// +     for non-commercial use (directly or indirectly)
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// +     Commercial use (for excample: selling of MikroKopters, selling of PCBs, assembly, ...) is only permitted
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// +     with our written permission
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// +   * If sources or documentations are redistributet on other webpages, out webpage (http://www.MikroKopter.de) must be
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// +     clearly linked as origin
39
// +   * porting to systems other than hardware from www.mikrokopter.de is not allowed
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// +  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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// +  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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// +  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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// +  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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// +  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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// +  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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// +  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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// +  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN// +  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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// +  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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// +  POSSIBILITY OF SUCH DAMAGE.
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// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
51
 
52
/************************************************************************/
53
/* Flight Attitude                                                      */
54
/************************************************************************/
55
 
56
#include <stdlib.h>
57
#include <avr/io.h>
58
 
59
#include "attitude.h"
60
#include "dongfangMath.h"
61
 
62
// where our main data flow comes from.
63
#include "analog.h"
64
 
65
#include "configuration.h"
66
 
67
// Some calculations are performed depending on some stick related things.
68
#include "controlMixer.h"
69
 
70
// For Servo_On / Off
71
// #include "timer2.h"
72
 
73
#ifdef USE_MK3MAG
74
#include "mk3mag.h"
75
#include "gps.h"
76
#endif
77
#define CHECK_MIN_MAX(value, min, max) {if(value < min) value = min; else if(value > max) value = max;}
78
 
79
/*
80
 * Gyro readings, as read from the analog module. It would have been nice to flow
81
 * them around between the different calculations as a struct or array (doing
82
 * things functionally without side effects) but this is shorter and probably
83
 * faster too.
84
 * The variables are overwritten at each attitude calculation invocation - the values
85
 * are not preserved or reused.
86
 */
87
int16_t pitchRate, rollRate, yawRate;
88
 
89
// With different (less) filtering
90
int16_t pitchRate_PID, rollRate_PID;
91
int16_t pitchDifferential, rollDifferential;
92
 
93
/*
94
 * Gyro readings, after performing "axis coupling" - that is, the transfomation
95
 * of rotation rates from the airframe-local coordinate system to a ground-fixed
96
 * coordinate system. If axis copling is disabled, the gyro readings will be
97
 * copied into these directly.
98
 * These are global for the same pragmatic reason as with the gyro readings.
99
 * The variables are overwritten at each attitude calculation invocation - the values
100
 * are not preserved or reused.
101
 */
102
int16_t ACPitchRate, ACRollRate, ACYawRate;
103
 
104
/*
105
 * Gyro integrals. These are the rotation angles of the airframe compared to the
106
 * horizontal plane, yaw relative to yaw at start.
107
 */
108
int32_t pitchAngle, rollAngle, yawAngle;
109
 
110
int readingHeight = 0;
111
 
112
// compass course
113
int16_t compassHeading = -1; // negative angle indicates invalid data.
114
int16_t compassCourse = -1;
115
int16_t compassOffCourse = 0;
116
uint16_t updateCompassCourse = 0;
117
uint8_t compassCalState = 0;
118
 
119
// uint8_t FunnelCourse = 0;
120
uint16_t badCompassHeading = 500;
121
int32_t yawGyroHeading; // Yaw Gyro Integral supported by compass
122
 
123
int32_t turnOver180 = GYRO_DEG_FACTOR_PITCHROLL * 180L;
124
int32_t turnOver360 = GYRO_DEG_FACTOR_PITCHROLL * 360L;
125
 
126
int32_t pitchCorrectionSum = 0, rollCorrectionSum = 0;
127
 
128
/*
129
 * Experiment: Compensating for dynamic-induced gyro biasing.
130
 */
131
int16_t dynamicOffsetPitch = 0, dynamicOffsetRoll = 0, dynamicOffsetYaw = 0;
132
// int16_t savedDynamicOffsetPitch = 0, savedDynamicOffsetRoll = 0;
133
// int32_t dynamicCalPitch, dynamicCalRoll, dynamicCalYaw;
134
// int16_t dynamicCalCount;
135
 
136
/************************************************************************
137
 * Set inclination angles from the acc. sensor data.                    
138
 * If acc. sensors are not used, set to zero.                          
139
 * TODO: One could use inverse sine to calculate the angles more        
140
 * accurately, but sinc: 1) the angles are rather at times when it      
141
 * makes sense to set the integrals (standing on ground, or flying at  
142
 * constant speed, and 2) at small angles a, sin(a) ~= constant * a,    
143
 * it is hardly worth the trouble.                                      
144
 ************************************************************************/
145
 
146
int32_t getPitchAngleEstimateFromAcc(void) {
147
  return GYRO_ACC_FACTOR * (int32_t)filteredPitchAxisAcc;
148
}
149
 
150
int32_t getRollAngleEstimateFromAcc(void) {
151
  return GYRO_ACC_FACTOR * (int32_t)filteredRollAxisAcc;
152
}
153
 
154
void setStaticAttitudeAngles(void) {
155
#ifdef ATTITUDE_USE_ACC_SENSORS
156
  pitchAngle = getPitchAngleEstimateFromAcc();
157
  rollAngle = getRollAngleEstimateFromAcc();
158
#else
159
  pitchAngle = 0;
160
  rollAngle = 0;
161
#endif
162
}
163
 
164
/************************************************************************
165
 * Neutral Readings                                                    
166
 ************************************************************************/
167
void attitude_setNeutral(void) {
168
  // Servo_Off(); // disable servo output. TODO: Why bother? The servos are going to make a jerk anyway.
169
  dynamicParams.AxisCoupling1 = dynamicParams.AxisCoupling2 = 0;
170
 
171
  dynamicOffsetPitch = dynamicOffsetRoll = 0;
172
 
173
  // Calibrate hardware.
174
  analog_calibrate();
175
 
176
  // reset gyro readings
177
  pitchRate = rollRate = yawRate = 0;
178
 
179
  // reset gyro integrals to acc guessing
180
  setStaticAttitudeAngles();
181
  yawAngle = 0;
182
 
183
  // update compass course to current heading
184
  compassCourse = compassHeading;
185
  // Inititialize YawGyroIntegral value with current compass heading
186
  yawGyroHeading = (int32_t)compassHeading * GYRO_DEG_FACTOR_YAW;
187
 
188
  // Servo_On(); //enable servo output
189
}
190
 
191
/************************************************************************
192
 * Get sensor data from the analog module, and release the ADC          
193
 * TODO: Ultimately, the analog module could do this (instead of dumping
194
 * the values into variables).                                          
195
 *************************************************************************/
196
void getAnalogData(void) {
197
  // For the differential calculation. Diff. is not supported right now.
198
  // int16_t d2Pitch, d2Roll;
199
  pitchRate_PID = (hiResPitchGyro + dynamicOffsetPitch) / HIRES_GYRO_INTEGRATION_FACTOR;
200
  pitchRate = (filteredHiResPitchGyro + dynamicOffsetPitch) / HIRES_GYRO_INTEGRATION_FACTOR;
201
  pitchDifferential = pitchGyroD;
202
 
203
  rollRate_PID = (hiResRollGyro + dynamicOffsetRoll) / HIRES_GYRO_INTEGRATION_FACTOR;
204
  rollRate = (filteredHiResRollGyro + dynamicOffsetRoll) / HIRES_GYRO_INTEGRATION_FACTOR;
205
  rollDifferential = rollGyroD;
206
 
207
  yawRate = yawGyro + dynamicOffsetYaw;
208
 
209
  // We are done reading variables from the analog module. Interrupt-driven sensor reading may restart.
210
  // TODO: Is that not a little early to measure for next control invocation?
211
  analogDataReady = 0;
212
  analog_start();
213
}
214
 
215
/************************************************************************
216
 * Axis coupling, H&I Style                                            
217
 * Currently not working (and there is a bug in it,
218
 * which causes unstable flight in heading-hold mode).
219
 ************************************************************************/
220
void H_and_I_axisCoupling(void) {
221
  int32_t tmpl = 0, tmpl2 = 0, tmp13 = 0, tmp14 = 0;
222
  int16_t CouplingNickRoll = 0, CouplingRollNick = 0;
223
 
224
  tmp13 = (rollRate * pitchAngle) / 2048L;
225
  tmp13 *= dynamicParams.AxisCoupling2; // 65
226
  tmp13 /= 4096L;
227
  CouplingNickRoll = tmp13;
228
 
229
  tmp14 = (pitchRate * rollAngle) / 2048L;
230
  tmp14 *= dynamicParams.AxisCoupling2; // 65
231
  tmp14 /= 4096L;
232
  CouplingRollNick = tmp14;
233
 
234
  tmp14 -= tmp13;
235
 
236
  ACYawRate = yawRate + tmp14;
237
 
238
  /*
239
  if(!dynamicParams.AxisCouplingYawCorrection) ACYawRate = yawRate - tmp14 / 2; // force yaw
240
  else ACYawRate
241
  */
242
 
243
  tmpl = ((yawRate + tmp14) * pitchAngle) / 2048L;
244
  tmpl *= dynamicParams.AxisCoupling1;
245
  tmpl /= 4096L;
246
 
247
  tmpl2 = ((yawRate + tmp14) * rollAngle) / 2048L;
248
  tmpl2 *= dynamicParams.AxisCoupling1;
249
  tmpl2 /= 4096L;
250
 
251
  // if(abs(yawRate > 64)) {
252
  // if(labs(tmpl) > 128 || labs(tmpl2) > 128) FunnelCourse = 1;
253
  // }
254
 
255
  ACPitchRate = pitchRate - tmpl2 + tmpl / 100L;
256
  ACRollRate = rollRate + tmpl - tmpl2 / 100L;
257
}
258
 
259
/*
260
 * This is the standard flight-style coordinate system transformation
261
 * (from airframe-local axes to a ground-based system). For some reason
262
 * the MK uses a left-hand coordinate system. The tranformation has been
263
 * changed accordingly.
264
 */
265
void trigAxisCoupling(void) {
266
  int16_t cospitch = int_cos(pitchAngle);
267
  int16_t cosroll =  int_cos(rollAngle);
268
  int16_t sinroll =  int_sin(rollAngle);
269
  int16_t tanpitch = int_tan(pitchAngle);
270
#define ANTIOVF 1024
271
  ACPitchRate =            ((int32_t)pitchRate * cosroll              + (int32_t)yawRate * sinroll)                       /  (int32_t)MATH_UNIT_FACTOR;
272
  ACRollRate = rollRate + (((int32_t)pitchRate * sinroll / ANTIOVF * tanpitch  - (int32_t)yawRate * int_cos(rollAngle) / ANTIOVF * tanpitch) / ((int32_t)MATH_UNIT_FACTOR / ANTIOVF * MATH_UNIT_FACTOR));
273
  ACYawRate =             (-(int32_t)pitchRate * sinroll) / cospitch + ((int32_t)yawRate * cosroll) / cospitch;
274
}
275
 
276
void integrate(void) {
277
  // First, perform axis coupling. If disabled xxxRate is just copied to ACxxxRate.
278
  if(!looping && (staticParams.GlobalConfig & CFG_AXIS_COUPLING_ACTIVE)) {
279
    // The rotary rate limiter bit is abused for selecting axis coupling algorithm instead.
280
    if (staticParams.GlobalConfig & CFG_ROTARY_RATE_LIMITER)
281
      trigAxisCoupling();    
282
    else
283
      H_and_I_axisCoupling();
284
  } else {
285
    ACPitchRate = pitchRate;
286
    ACRollRate = rollRate;
287
    ACYawRate = yawRate;
288
  }
289
 
290
  DebugOut.Analog[3] = pitchRate;
291
  DebugOut.Analog[3 + 3] = ACPitchRate;
292
  DebugOut.Analog[4] = rollRate;
293
  DebugOut.Analog[4 + 3] = ACRollRate;
294
  DebugOut.Analog[5] = yawRate;
295
  DebugOut.Analog[5 + 3] = ACYawRate;
296
 
297
  /*
298
  DebugOut.Analog[9] = int_cos(pitchAngle);
299
  DebugOut.Analog[10] = int_sin(pitchAngle);
300
  DebugOut.Analog[11] = int_tan(pitchAngle);
301
  */
302
 
303
  /*
304
   * Yaw
305
   * Calculate yaw gyro integral (~ to rotation angle)
306
   * Limit yawGyroHeading proportional to 0 deg to 360 deg
307
   */
308
  yawGyroHeading += ACYawRate;
309
  yawAngle += ACYawRate;
310
  if(yawGyroHeading >= (360L * GYRO_DEG_FACTOR_YAW))    yawGyroHeading -= 360L * GYRO_DEG_FACTOR_YAW;  // 360 deg. wrap
311
  if(yawGyroHeading < 0)                                yawGyroHeading += 360L * GYRO_DEG_FACTOR_YAW;
312
 
313
  /*
314
   * Pitch axis integration and range boundary wrap.
315
   */
316
  pitchAngle += ACPitchRate;
317
  if(pitchAngle > turnOver180) {
318
    pitchAngle -= turnOver360;
319
  } else if (pitchAngle <= -turnOver180) {
320
    pitchAngle += turnOver360;
321
  }
322
 
323
  /*
324
   * Pitch axis integration and range boundary wrap.
325
   */
326
  rollAngle  += ACRollRate;
327
  if(rollAngle > turnOver180) {
328
    rollAngle -= turnOver360;
329
  } else if (rollAngle <= -turnOver180) {
330
    rollAngle += turnOver360;
331
  }
332
}
333
 
334
/************************************************************************
335
 * A kind of 0'th order integral correction, that corrects the integrals
336
 * directly. This is the "gyroAccFactor" stuff in the original code.
337
 * There is (there) also what I would call a  "minus 1st order correction"
338
 * - it corrects the differential of the integral = the gyro offsets.
339
 * That should only be necessary with drifty gyros like ENC-03.
340
 ************************************************************************/
341
void correctIntegralsByAcc0thOrder(void) {
342
  // TODO: Consider changing this to: Only correct when integrals are less than ...., or only correct when angular velocities
343
  // are less than ....., or reintroduce Kalman.
344
  // Well actually the Z axis acc. check is not so silly.
345
  if(!looping && //((ZAxisAcc >= -4) || (MKFlags & MKFLAG_MOTOR_RUN))) { // if not looping in any direction
346
     ZAxisAcc >= -dynamicParams.UserParams[7] && ZAxisAcc <= dynamicParams.UserParams[7]) {
347
    DebugOut.Digital[0] = 1;
348
 
349
    uint8_t permilleAcc = staticParams.GyroAccFactor; // NOTE!!! The meaning of this value has changed!!
350
    uint8_t debugFullWeight = 1;
351
 
352
    int32_t accDerivedPitch = getPitchAngleEstimateFromAcc();
353
    int32_t accDerivedRoll = getRollAngleEstimateFromAcc();
354
 
355
    if((maxControlPitch > 64) || (maxControlRoll > 64)) { // reduce effect during stick commands
356
      permilleAcc /= 2;
357
      debugFullWeight = 0;
358
    }
359
 
360
    if(abs(controlYaw) > 25) { // reduce further if yaw stick is active
361
      permilleAcc /= 2;
362
      debugFullWeight = 0;
363
    }
364
 
365
    /*
366
     * Add to each sum: The amount by which the angle is changed just below.
367
     */
368
    pitchCorrectionSum += permilleAcc * (accDerivedPitch - pitchAngle);
369
    rollCorrectionSum += permilleAcc * (accDerivedRoll - rollAngle);
370
 
371
    // There should not be a risk of overflow here, since the integrals do not exceed a few 100000.
372
    pitchAngle = ((int32_t)(1000 - permilleAcc) * pitchAngle + (int32_t)permilleAcc * accDerivedPitch) / 1000L;
373
    rollAngle = ((int32_t)(1000 - permilleAcc) * rollAngle + (int32_t)permilleAcc * accDerivedRoll) / 1000L;
374
 
375
    DebugOut.Digital[1] = debugFullWeight;
376
  } else {
377
    DebugOut.Digital[0] = 0;
378
  }
379
}
380
 
381
/************************************************************************
382
 * This is an attempt to correct not the error in the angle integrals
383
 * (that happens in correctIntegralsByAcc0thOrder above) but rather the
384
 * cause of it: Gyro drift, vibration and rounding errors.
385
 * All the corrections made in correctIntegralsByAcc0thOrder over
386
 * MINUSFIRSTORDERCORRECTION_TIME cycles are summed up. This number is
387
 * then divided by MINUSFIRSTORDERCORRECTION_TIME to get the approx.
388
 * correction that should have been applied to each iteration to fix
389
 * the error. This is then added to the dynamic offsets.
390
 ************************************************************************/
391
// 2 times / sec.
392
#define DRIFTCORRECTION_TIME 488/2
393
void driftCompensation(void) {
394
  static int16_t timer = DRIFTCORRECTION_TIME;
395
  int16_t deltaCompensation;
396
  if (! --timer) {
397
    timer = DRIFTCORRECTION_TIME;
398
    deltaCompensation = ((pitchCorrectionSum + 1000L * DRIFTCORRECTION_TIME / 2) / 1000 / DRIFTCORRECTION_TIME);
399
    CHECK_MIN_MAX(deltaCompensation, -staticParams.DriftComp, staticParams.DriftComp);
400
    dynamicOffsetPitch += deltaCompensation / staticParams.GyroAccTrim;
401
 
402
    deltaCompensation = ((rollCorrectionSum + 1000L * DRIFTCORRECTION_TIME / 2) / 1000 / DRIFTCORRECTION_TIME);
403
    CHECK_MIN_MAX(deltaCompensation, -staticParams.DriftComp, staticParams.DriftComp);
404
    dynamicOffsetRoll += deltaCompensation / staticParams.GyroAccTrim;
405
 
406
    pitchCorrectionSum = rollCorrectionSum = 0;
407
 
408
    DebugOut.Analog[28] = dynamicOffsetPitch;
409
    DebugOut.Analog[29] = dynamicOffsetRoll;
410
  }
411
}
412
 
413
/************************************************************************
414
 * Main procedure.
415
 ************************************************************************/
416
void calculateFlightAttitude(void) {  
417
  getAnalogData();
418
  integrate();
419
#ifdef ATTITUDE_USE_ACC_SENSORS
420
  correctIntegralsByAcc0thOrder();
421
  driftCompensation();
422
#endif
423
}
424
 
425
/*
426
void updateCompass(void) {
427
  int16_t w, v, r,correction, error;
428
 
429
  if(compassCalState && !(MKFlags & MKFLAG_MOTOR_RUN)) {
430
    setCompassCalState();
431
  } else {
432
    // get maximum attitude angle
433
    w = abs(pitchAngle / 512);
434
    v = abs(rollAngle / 512);
435
    if(v > w) w = v;
436
    correction = w / 8 + 1;
437
    // calculate the deviation of the yaw gyro heading and the compass heading
438
    if (compassHeading < 0) error = 0; // disable yaw drift compensation if compass heading is undefined
439
    else error = ((540 + compassHeading - (yawGyroHeading / GYRO_DEG_FACTOR_YAW)) % 360) - 180;
440
    if(abs(yawRate) > 128) { // spinning fast
441
      error = 0;
442
    }
443
    if(!badCompassHeading && w < 25) {
444
      if(updateCompassCourse) {
445
        beep(200);
446
        yawGyroHeading = (int32_t)compassHeading * GYRO_DEG_FACTOR_YAW;
447
        compassCourse = (int16_t)(yawGyroHeading / GYRO_DEG_FACTOR_YAW);
448
        updateCompassCourse = 0;
449
      }
450
    }
451
    yawGyroHeading += (error * 8) / correction;
452
    w = (w * dynamicParams.CompassYawEffect) / 32;
453
    w = dynamicParams.CompassYawEffect - w;
454
    if(w >= 0) {
455
      if(!badCompassHeading) {
456
        v = 64 + (maxControlPitch + maxControlRoll) / 8;
457
        // calc course deviation
458
        r = ((540 + (yawGyroHeading / GYRO_DEG_FACTOR_YAW) - compassCourse) % 360) - 180;
459
        v = (r * w) / v; // align to compass course
460
        // limit yaw rate
461
        w = 3 * dynamicParams.CompassYawEffect;
462
        if (v > w) v = w;
463
        else if (v < -w) v = -w;
464
        yawAngle += v;
465
      }
466
      else
467
        { // wait a while
468
          badCompassHeading--;
469
        }
470
    }
471
    else {  // ignore compass at extreme attitudes for a while
472
      badCompassHeading = 500;
473
    }
474
  }
475
}
476
*/
477
 
478
/*
479
 * This is part of an experiment to measure average sensor offsets caused by motor vibration,
480
 * and to compensate them away. It brings about some improvement, but no miracles.
481
 * As long as the left stick is kept in the start-motors position, the dynamic compensation
482
 * will measure the effect of vibration, to use for later compensation. So, one should keep
483
 * the stick in the start-motors position for a few seconds, till all motors run (at the wrong
484
 * speed unfortunately... must find a better way)
485
 */
486
/*
487
void attitude_startDynamicCalibration(void) {
488
  dynamicCalPitch = dynamicCalRoll = dynamicCalYaw = dynamicCalCount = 0;
489
  savedDynamicOffsetPitch = savedDynamicOffsetRoll = 1000;
490
}
491
 
492
void attitude_continueDynamicCalibration(void) {
493
  // measure dynamic offset now...
494
  dynamicCalPitch += hiResPitchGyro;
495
  dynamicCalRoll += hiResRollGyro;
496
  dynamicCalYaw += rawYawGyroSum;
497
  dynamicCalCount++;
498
 
499
  // Param6: Manual mode. The offsets are taken from Param7 and Param8.
500
  if (dynamicParams.UserParam6 || 1) { // currently always enabled.
501
    // manual mode
502
    dynamicOffsetPitch = dynamicParams.UserParam7 - 128;
503
    dynamicOffsetRoll = dynamicParams.UserParam8 - 128;
504
  } else {
505
    // use the sampled value (does not seem to work so well....)
506
    dynamicOffsetPitch = savedDynamicOffsetPitch = -dynamicCalPitch / dynamicCalCount;
507
    dynamicOffsetRoll = savedDynamicOffsetRoll = -dynamicCalRoll / dynamicCalCount;
508
    dynamicOffsetYaw = -dynamicCalYaw / dynamicCalCount;
509
  }
510
 
511
  // keep resetting these meanwhile, to avoid accumulating errors.
512
  setStaticAttitudeIntegrals();
513
  yawAngle = 0;
514
}
515
*/