forked from rjsmith1999/ProjectStompRocket
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathIMU.ino
254 lines (222 loc) · 10.7 KB
/
IMU.ino
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
void setup_IMU()
{
Wire.begin();
digitalWrite(LED_GREEN, HIGH);
// Read the WHO_AM_I register, this is a good test of communication
byte c = myIMU.readByte(MPU9250_ADDRESS, WHO_AM_I_MPU9250);
Serial.print("MPU9250 "); Serial.print("I AM "); Serial.print(c, HEX);
Serial.print(" I should be "); Serial.println(0x71, HEX);
if (c == 0x71) // WHO_AM_I should always be 0x68
{
Serial.println("MPU9250 is online...");
// Start by performing self test and reporting values
myIMU.MPU9250SelfTest(myIMU.SelfTest);
Serial.print("x-axis self test: acceleration trim within : ");
Serial.print(myIMU.SelfTest[0],1); Serial.println("% of factory value");
Serial.print("y-axis self test: acceleration trim within : ");
Serial.print(myIMU.SelfTest[1],1); Serial.println("% of factory value");
Serial.print("z-axis self test: acceleration trim within : ");
Serial.print(myIMU.SelfTest[2],1); Serial.println("% of factory value");
Serial.print("x-axis self test: gyration trim within : ");
Serial.print(myIMU.SelfTest[3],1); Serial.println("% of factory value");
Serial.print("y-axis self test: gyration trim within : ");
Serial.print(myIMU.SelfTest[4],1); Serial.println("% of factory value");
Serial.print("z-axis self test: gyration trim within : ");
Serial.print(myIMU.SelfTest[5],1); Serial.println("% of factory value");
// Calibrate gyro and accelerometers, load biases in bias registers
myIMU.calibrateMPU9250(myIMU.gyroBias, myIMU.accelBias);
myIMU.initMPU9250();
// Initialize device for active mode read of acclerometer, gyroscope, and
// temperature
Serial.println("MPU9250 initialized for active data mode....");
// Read the WHO_AM_I register of the magnetometer, this is a good test of
// communication
byte d = myIMU.readByte(AK8963_ADDRESS, WHO_AM_I_AK8963);
Serial.print("AK8963 "); Serial.print("I AM "); Serial.print(d, HEX);
Serial.print(" I should be "); Serial.println(0x48, HEX);
// Get magnetometer calibration from AK8963 ROM
myIMU.initAK8963(myIMU.magCalibration);
// Initialize device for active mode read of magnetometer
Serial.println("AK8963 initialized for active data mode....");
// Serial.println("Calibration values: ");
Serial.print("X-Axis sensitivity adjustment value ");
Serial.println(myIMU.magCalibration[0], 2);
Serial.print("Y-Axis sensitivity adjustment value ");
Serial.println(myIMU.magCalibration[1], 2);
Serial.print("Z-Axis sensitivity adjustment value ");
Serial.println(myIMU.magCalibration[2], 2);
digitalWrite(LED_GREEN, LOW); // turn off LED when setup is done
} // if (c == 0x71)
else
{
Serial.print("Could not connect to MPU9250: 0x");
Serial.println(c, HEX);
}
}
void read_IMU()
{
// If intPin goes high, all data registers have new data
// On interrupt, check if data ready interrupt
if (myIMU.readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01)
{
myIMU.readAccelData(myIMU.accelCount); // Read the x/y/z adc values
myIMU.getAres();
// Now we'll calculate the accleration value into actual g's
// This depends on scale being set
myIMU.ax = (float)myIMU.accelCount[0]*myIMU.aRes; // - accelBias[0];
myIMU.ay = (float)myIMU.accelCount[1]*myIMU.aRes; // - accelBias[1];
myIMU.az = (float)myIMU.accelCount[2]*myIMU.aRes; // - accelBias[2];
myIMU.readGyroData(myIMU.gyroCount); // Read the x/y/z adc values
myIMU.getGres();
// Calculate the gyro value into actual degrees per second
// This depends on scale being set
myIMU.gx = (float)myIMU.gyroCount[0]*myIMU.gRes;
myIMU.gy = (float)myIMU.gyroCount[1]*myIMU.gRes;
myIMU.gz = (float)myIMU.gyroCount[2]*myIMU.gRes;
myIMU.readMagData(myIMU.magCount); // Read the x/y/z adc values
myIMU.getMres();
// User environmental x-axis correction in milliGauss, should be
// automatically calculated
myIMU.magbias[0] = +470.;
// User environmental x-axis correction in milliGauss TODO axis??
myIMU.magbias[1] = +120.;
// User environmental x-axis correction in milliGauss
myIMU.magbias[2] = +125.;
// Calculate the magnetometer values in milliGauss
// Include factory calibration per data sheet and user environmental
// corrections
// Get actual magnetometer value, this depends on scale being set
myIMU.mx = (float)myIMU.magCount[0]*myIMU.mRes*myIMU.magCalibration[0] -
myIMU.magbias[0];
myIMU.my = (float)myIMU.magCount[1]*myIMU.mRes*myIMU.magCalibration[1] -
myIMU.magbias[1];
myIMU.mz = (float)myIMU.magCount[2]*myIMU.mRes*myIMU.magCalibration[2] -
myIMU.magbias[2];
} // if (readByte(MPU9250_ADDRESS, INT_STATUS) & 0x01)
myIMU.updateTime();
// Sensors x (y)-axis of the accelerometer is aligned with the y (x)-axis of
// the magnetometer; the magnetometer z-axis (+ down) is opposite to z-axis
// (+ up) of accelerometer and gyro! We have to make some allowance for this
// orientationmismatch in feeding the output to the quaternion filter. For the
// MPU-9250, we have chosen a magnetic rotation that keeps the sensor forward
// along the x-axis just like in the LSM9DS0 sensor. This rotation can be
// modified to allow any convenient orientation convention. This is ok by
// aircraft orientation standards! Pass gyro rate as rad/s
// MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, my, mx, mz);
MahonyQuaternionUpdate(myIMU.ax, myIMU.ay, myIMU.az, myIMU.gx*DEG_TO_RAD,
myIMU.gy*DEG_TO_RAD, myIMU.gz*DEG_TO_RAD, myIMU.my,
myIMU.mx, myIMU.mz, myIMU.deltat);
if (!ARHS)
{
myIMU.delt_t = millis() - myIMU.count;
if (myIMU.delt_t > 500)
{
myIMU.tempCount = myIMU.readTempData(); // Read the adc values
// Temperature in degrees Centigrade
myIMU.temperature = ((float) myIMU.tempCount) / 333.87 + 21.0;
if(SerialDebug)
{
// Print acceleration values in milligs!
Serial.print("X-acceleration: "); Serial.print(1000*myIMU.ax);
Serial.print(" mg ");
Serial.print("Y-acceleration: "); Serial.print(1000*myIMU.ay);
Serial.print(" mg ");
Serial.print("Z-acceleration: "); Serial.print(1000*myIMU.az);
Serial.println(" mg ");
// Print gyro values in degree/sec
Serial.print("X-gyro rate: "); Serial.print(myIMU.gx, 3);
Serial.print(" degrees/sec ");
Serial.print("Y-gyro rate: "); Serial.print(myIMU.gy, 3);
Serial.print(" degrees/sec ");
Serial.print("Z-gyro rate: "); Serial.print(myIMU.gz, 3);
Serial.println(" degrees/sec");
// Print mag values in degree/sec
Serial.print("X-mag field: "); Serial.print(myIMU.mx);
Serial.print(" mG ");
Serial.print("Y-mag field: "); Serial.print(myIMU.my);
Serial.print(" mG ");
Serial.print("Z-mag field: "); Serial.print(myIMU.mz);
Serial.println(" mG");
// Print temperature in degrees Centigrade
Serial.print("Temperature is "); Serial.print(myIMU.temperature, 1);
Serial.println(" degrees C");
}
myIMU.count = millis();
} // if (myIMU.delt_t > 500)
} // if (!AHRS)
else
{
// Serial print and/or display at 0.5 s rate independent of data rates
myIMU.delt_t = millis() - myIMU.count;
// update LCD once per half-second independent of read rate
if (myIMU.delt_t > 500)
{
if(SerialDebug)
{
Serial.print("ax = "); Serial.print((int)1000*myIMU.ax);
Serial.print(" ay = "); Serial.print((int)1000*myIMU.ay);
Serial.print(" az = "); Serial.print((int)1000*myIMU.az);
Serial.println(" mg");
Serial.print("gx = "); Serial.print( myIMU.gx, 2);
Serial.print(" gy = "); Serial.print( myIMU.gy, 2);
Serial.print(" gz = "); Serial.print( myIMU.gz, 2);
Serial.println(" deg/s");
Serial.print("mx = "); Serial.print( (int)myIMU.mx );
Serial.print(" my = "); Serial.print( (int)myIMU.my );
Serial.print(" mz = "); Serial.print( (int)myIMU.mz );
Serial.println(" mG");
Serial.print("q0 = "); Serial.print(*getQ());
Serial.print(" qx = "); Serial.print(*(getQ() + 1));
Serial.print(" qy = "); Serial.print(*(getQ() + 2));
Serial.print(" qz = "); Serial.println(*(getQ() + 3));
}
// Define output variables from updated quaternion---these are Tait-Bryan
// angles, commonly used in aircraft orientation. In this coordinate system,
// the positive z-axis is down toward Earth. Yaw is the angle between Sensor
// x-axis and Earth magnetic North (or true North if corrected for local
// declination, looking down on the sensor positive yaw is counterclockwise.
// Pitch is angle between sensor x-axis and Earth ground plane, toward the
// Earth is positive, up toward the sky is negative. Roll is angle between
// sensor y-axis and Earth ground plane, y-axis up is positive roll. These
// arise from the definition of the homogeneous rotation matrix constructed
// from quaternions. Tait-Bryan angles as well as Euler angles are
// non-commutative; that is, the get the correct orientation the rotations
// must be applied in the correct order which for this configuration is yaw,
// pitch, and then roll.
// For more see
// http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles
// which has additional links.
myIMU.yaw = atan2(2.0f * (*(getQ()+1) * *(getQ()+2) + *getQ() *
*(getQ()+3)), *getQ() * *getQ() + *(getQ()+1) * *(getQ()+1)
- *(getQ()+2) * *(getQ()+2) - *(getQ()+3) * *(getQ()+3));
myIMU.pitch = -asin(2.0f * (*(getQ()+1) * *(getQ()+3) - *getQ() *
*(getQ()+2)));
myIMU.roll = atan2(2.0f * (*getQ() * *(getQ()+1) + *(getQ()+2) *
*(getQ()+3)), *getQ() * *getQ() - *(getQ()+1) * *(getQ()+1)
- *(getQ()+2) * *(getQ()+2) + *(getQ()+3) * *(getQ()+3));
myIMU.pitch *= RAD_TO_DEG;
myIMU.yaw *= RAD_TO_DEG;
// Declination of SparkFun Electronics (40°05'26.6"N 105°11'05.9"W) is
// 8° 30' E ± 0° 21' (or 8.5°) on 2016-07-19
// - http://www.ngdc.noaa.gov/geomag-web/#declination
// myIMU.yaw -= 8.5;
myIMU.yaw -= 11.25; // Helaman Halls area
myIMU.roll *= RAD_TO_DEG;
if(SerialDebug)
{
Serial.print("Yaw, Pitch, Roll: ");
Serial.print(myIMU.yaw, 2);
Serial.print(", ");
Serial.print(myIMU.pitch, 2);
Serial.print(", ");
Serial.println(myIMU.roll, 2);
Serial.print("rate = ");
Serial.print((float)myIMU.sumCount/myIMU.sum, 2);
Serial.println(" Hz");
}
myIMU.count = millis();
myIMU.sumCount = 0;
myIMU.sum = 0;
} // if (myIMU.delt_t > 500)
} // if (AHRS)
}