Ian Molesworth
/
IMUfilter
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IMUfilter.cpp@2:202906c5fadd, 2011-02-12 (annotated)
- Committer:
- nimbusgb
- Date:
- Sat Feb 12 15:29:40 2011 +0000
- Revision:
- 2:202906c5fadd
- Parent:
- 1:4b0e8441f099
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| nimbusgb | 0:6a5296aa7dbf | 1 | /** |
| nimbusgb | 0:6a5296aa7dbf | 2 | * @author Aaron Berk |
| nimbusgb | 0:6a5296aa7dbf | 3 | * |
| nimbusgb | 0:6a5296aa7dbf | 4 | * @section LICENSE |
| nimbusgb | 0:6a5296aa7dbf | 5 | * |
| nimbusgb | 0:6a5296aa7dbf | 6 | * Copyright (c) 2010 ARM Limited |
| nimbusgb | 0:6a5296aa7dbf | 7 | * |
| nimbusgb | 0:6a5296aa7dbf | 8 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| nimbusgb | 0:6a5296aa7dbf | 9 | * of this software and associated documentation files (the "Software"), to deal |
| nimbusgb | 0:6a5296aa7dbf | 10 | * in the Software without restriction, including without limitation the rights |
| nimbusgb | 0:6a5296aa7dbf | 11 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| nimbusgb | 0:6a5296aa7dbf | 12 | * copies of the Software, and to permit persons to whom the Software is |
| nimbusgb | 0:6a5296aa7dbf | 13 | * furnished to do so, subject to the following conditions: |
| nimbusgb | 0:6a5296aa7dbf | 14 | * |
| nimbusgb | 0:6a5296aa7dbf | 15 | * The above copyright notice and this permission notice shall be included in |
| nimbusgb | 0:6a5296aa7dbf | 16 | * all copies or substantial portions of the Software. |
| nimbusgb | 0:6a5296aa7dbf | 17 | * |
| nimbusgb | 0:6a5296aa7dbf | 18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| nimbusgb | 0:6a5296aa7dbf | 19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| nimbusgb | 0:6a5296aa7dbf | 20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| nimbusgb | 0:6a5296aa7dbf | 21 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| nimbusgb | 0:6a5296aa7dbf | 22 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| nimbusgb | 0:6a5296aa7dbf | 23 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| nimbusgb | 0:6a5296aa7dbf | 24 | * THE SOFTWARE. |
| nimbusgb | 0:6a5296aa7dbf | 25 | * |
| nimbusgb | 0:6a5296aa7dbf | 26 | * @section DESCRIPTION |
| nimbusgb | 0:6a5296aa7dbf | 27 | * |
| nimbusgb | 0:6a5296aa7dbf | 28 | * IMU orientation filter developed by Sebastian Madgwick. |
| nimbusgb | 0:6a5296aa7dbf | 29 | * |
| nimbusgb | 0:6a5296aa7dbf | 30 | * Find more details about his paper here: |
| nimbusgb | 0:6a5296aa7dbf | 31 | * |
| nimbusgb | 0:6a5296aa7dbf | 32 | * http://code.google.com/p/imumargalgorithm30042010sohm/ |
| nimbusgb | 0:6a5296aa7dbf | 33 | */ |
| nimbusgb | 0:6a5296aa7dbf | 34 | |
| nimbusgb | 0:6a5296aa7dbf | 35 | /** |
| nimbusgb | 0:6a5296aa7dbf | 36 | * Includes |
| nimbusgb | 0:6a5296aa7dbf | 37 | */ |
| nimbusgb | 0:6a5296aa7dbf | 38 | #include "IMUfilter.h" |
| nimbusgb | 0:6a5296aa7dbf | 39 | |
| nimbusgb | 0:6a5296aa7dbf | 40 | IMUfilter::IMUfilter(double rate, double gyroscopeMeasurementError){ |
| nimbusgb | 0:6a5296aa7dbf | 41 | |
| nimbusgb | 0:6a5296aa7dbf | 42 | firstUpdate = 0; |
| nimbusgb | 0:6a5296aa7dbf | 43 | |
| nimbusgb | 0:6a5296aa7dbf | 44 | //Quaternion orientation of earth frame relative to auxiliary frame. |
| nimbusgb | 0:6a5296aa7dbf | 45 | AEq_1 = 1; |
| nimbusgb | 0:6a5296aa7dbf | 46 | AEq_2 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 47 | AEq_3 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 48 | AEq_4 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 49 | |
| nimbusgb | 0:6a5296aa7dbf | 50 | //Estimated orientation quaternion elements with initial conditions. |
| nimbusgb | 0:6a5296aa7dbf | 51 | SEq_1 = 1; |
| nimbusgb | 0:6a5296aa7dbf | 52 | SEq_2 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 53 | SEq_3 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 54 | SEq_4 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 55 | |
| nimbusgb | 0:6a5296aa7dbf | 56 | //Sampling period (typical value is ~0.1s). |
| nimbusgb | 0:6a5296aa7dbf | 57 | deltat = rate; |
| nimbusgb | 0:6a5296aa7dbf | 58 | |
| nimbusgb | 0:6a5296aa7dbf | 59 | //Gyroscope measurement error (in degrees per second). |
| nimbusgb | 0:6a5296aa7dbf | 60 | gyroMeasError = gyroscopeMeasurementError; |
| nimbusgb | 0:6a5296aa7dbf | 61 | |
| nimbusgb | 0:6a5296aa7dbf | 62 | //Compute beta. |
| nimbusgb | 0:6a5296aa7dbf | 63 | beta = sqrt(3.0 / 4.0) * (PI * (gyroMeasError / 180.0)); |
| nimbusgb | 0:6a5296aa7dbf | 64 | |
| nimbusgb | 0:6a5296aa7dbf | 65 | } |
| nimbusgb | 0:6a5296aa7dbf | 66 | |
| nimbusgb | 0:6a5296aa7dbf | 67 | void IMUfilter::updateFilter(double w_x, double w_y, double w_z, double a_x, double a_y, double a_z) { |
| nimbusgb | 0:6a5296aa7dbf | 68 | |
| nimbusgb | 0:6a5296aa7dbf | 69 | //Local system variables. |
| nimbusgb | 0:6a5296aa7dbf | 70 | |
| nimbusgb | 0:6a5296aa7dbf | 71 | //Vector norm. |
| nimbusgb | 0:6a5296aa7dbf | 72 | double norm; |
| nimbusgb | 0:6a5296aa7dbf | 73 | //Quaternion rate from gyroscope elements. |
| nimbusgb | 0:6a5296aa7dbf | 74 | double SEqDot_omega_1; |
| nimbusgb | 0:6a5296aa7dbf | 75 | double SEqDot_omega_2; |
| nimbusgb | 0:6a5296aa7dbf | 76 | double SEqDot_omega_3; |
| nimbusgb | 0:6a5296aa7dbf | 77 | double SEqDot_omega_4; |
| nimbusgb | 0:6a5296aa7dbf | 78 | //Objective function elements. |
| nimbusgb | 0:6a5296aa7dbf | 79 | double f_1; |
| nimbusgb | 0:6a5296aa7dbf | 80 | double f_2; |
| nimbusgb | 0:6a5296aa7dbf | 81 | double f_3; |
| nimbusgb | 0:6a5296aa7dbf | 82 | //Objective function Jacobian elements. |
| nimbusgb | 0:6a5296aa7dbf | 83 | double J_11or24; |
| nimbusgb | 0:6a5296aa7dbf | 84 | double J_12or23; |
| nimbusgb | 0:6a5296aa7dbf | 85 | double J_13or22; |
| nimbusgb | 0:6a5296aa7dbf | 86 | double J_14or21; |
| nimbusgb | 0:6a5296aa7dbf | 87 | double J_32; |
| nimbusgb | 0:6a5296aa7dbf | 88 | double J_33; |
| nimbusgb | 0:6a5296aa7dbf | 89 | //Objective function gradient elements. |
| nimbusgb | 0:6a5296aa7dbf | 90 | double nablaf_1; |
| nimbusgb | 0:6a5296aa7dbf | 91 | double nablaf_2; |
| nimbusgb | 0:6a5296aa7dbf | 92 | double nablaf_3; |
| nimbusgb | 0:6a5296aa7dbf | 93 | double nablaf_4; |
| nimbusgb | 0:6a5296aa7dbf | 94 | |
| nimbusgb | 0:6a5296aa7dbf | 95 | //Auxiliary variables to avoid reapeated calculations. |
| nimbusgb | 0:6a5296aa7dbf | 96 | double halfSEq_1 = 0.5 * SEq_1; |
| nimbusgb | 0:6a5296aa7dbf | 97 | double halfSEq_2 = 0.5 * SEq_2; |
| nimbusgb | 0:6a5296aa7dbf | 98 | double halfSEq_3 = 0.5 * SEq_3; |
| nimbusgb | 0:6a5296aa7dbf | 99 | double halfSEq_4 = 0.5 * SEq_4; |
| nimbusgb | 0:6a5296aa7dbf | 100 | double twoSEq_1 = 2.0 * SEq_1; |
| nimbusgb | 0:6a5296aa7dbf | 101 | double twoSEq_2 = 2.0 * SEq_2; |
| nimbusgb | 0:6a5296aa7dbf | 102 | double twoSEq_3 = 2.0 * SEq_3; |
| nimbusgb | 0:6a5296aa7dbf | 103 | |
| nimbusgb | 0:6a5296aa7dbf | 104 | //Compute the quaternion rate measured by gyroscopes. |
| nimbusgb | 0:6a5296aa7dbf | 105 | SEqDot_omega_1 = -halfSEq_2 * w_x - halfSEq_3 * w_y - halfSEq_4 * w_z; |
| nimbusgb | 0:6a5296aa7dbf | 106 | SEqDot_omega_2 = halfSEq_1 * w_x + halfSEq_3 * w_z - halfSEq_4 * w_y; |
| nimbusgb | 0:6a5296aa7dbf | 107 | SEqDot_omega_3 = halfSEq_1 * w_y - halfSEq_2 * w_z + halfSEq_4 * w_x; |
| nimbusgb | 0:6a5296aa7dbf | 108 | SEqDot_omega_4 = halfSEq_1 * w_z + halfSEq_2 * w_y - halfSEq_3 * w_x; |
| nimbusgb | 0:6a5296aa7dbf | 109 | |
| nimbusgb | 0:6a5296aa7dbf | 110 | //Normalise the accelerometer measurement. |
| nimbusgb | 0:6a5296aa7dbf | 111 | norm = sqrt(a_x * a_x + a_y * a_y + a_z * a_z); |
| nimbusgb | 0:6a5296aa7dbf | 112 | a_x /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 113 | a_y /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 114 | a_z /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 115 | |
| nimbusgb | 0:6a5296aa7dbf | 116 | //Compute the objective function and Jacobian. |
| nimbusgb | 0:6a5296aa7dbf | 117 | f_1 = twoSEq_2 * SEq_4 - twoSEq_1 * SEq_3 - a_x; |
| nimbusgb | 0:6a5296aa7dbf | 118 | f_2 = twoSEq_1 * SEq_2 + twoSEq_3 * SEq_4 - a_y; |
| nimbusgb | 0:6a5296aa7dbf | 119 | f_3 = 1.0 - twoSEq_2 * SEq_2 - twoSEq_3 * SEq_3 - a_z; |
| nimbusgb | 0:6a5296aa7dbf | 120 | //J_11 negated in matrix multiplication. |
| nimbusgb | 0:6a5296aa7dbf | 121 | J_11or24 = twoSEq_3; |
| nimbusgb | 0:6a5296aa7dbf | 122 | J_12or23 = 2 * SEq_4; |
| nimbusgb | 0:6a5296aa7dbf | 123 | //J_12 negated in matrix multiplication |
| nimbusgb | 0:6a5296aa7dbf | 124 | J_13or22 = twoSEq_1; |
| nimbusgb | 0:6a5296aa7dbf | 125 | J_14or21 = twoSEq_2; |
| nimbusgb | 0:6a5296aa7dbf | 126 | //Negated in matrix multiplication. |
| nimbusgb | 0:6a5296aa7dbf | 127 | J_32 = 2 * J_14or21; |
| nimbusgb | 0:6a5296aa7dbf | 128 | //Negated in matrix multiplication. |
| nimbusgb | 0:6a5296aa7dbf | 129 | J_33 = 2 * J_11or24; |
| nimbusgb | 0:6a5296aa7dbf | 130 | |
| nimbusgb | 0:6a5296aa7dbf | 131 | //Compute the gradient (matrix multiplication). |
| nimbusgb | 0:6a5296aa7dbf | 132 | nablaf_1 = J_14or21 * f_2 - J_11or24 * f_1; |
| nimbusgb | 0:6a5296aa7dbf | 133 | nablaf_2 = J_12or23 * f_1 + J_13or22 * f_2 - J_32 * f_3; |
| nimbusgb | 0:6a5296aa7dbf | 134 | nablaf_3 = J_12or23 * f_2 - J_33 * f_3 - J_13or22 * f_1; |
| nimbusgb | 0:6a5296aa7dbf | 135 | nablaf_4 = J_14or21 * f_1 + J_11or24 * f_2; |
| nimbusgb | 0:6a5296aa7dbf | 136 | |
| nimbusgb | 0:6a5296aa7dbf | 137 | //Normalise the gradient. |
| nimbusgb | 0:6a5296aa7dbf | 138 | norm = sqrt(nablaf_1 * nablaf_1 + nablaf_2 * nablaf_2 + nablaf_3 * nablaf_3 + nablaf_4 * nablaf_4); |
| nimbusgb | 0:6a5296aa7dbf | 139 | nablaf_1 /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 140 | nablaf_2 /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 141 | nablaf_3 /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 142 | nablaf_4 /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 143 | |
| nimbusgb | 0:6a5296aa7dbf | 144 | //Compute then integrate the estimated quaternion rate. |
| nimbusgb | 0:6a5296aa7dbf | 145 | SEq_1 += (SEqDot_omega_1 - (beta * nablaf_1)) * deltat; |
| nimbusgb | 0:6a5296aa7dbf | 146 | SEq_2 += (SEqDot_omega_2 - (beta * nablaf_2)) * deltat; |
| nimbusgb | 0:6a5296aa7dbf | 147 | SEq_3 += (SEqDot_omega_3 - (beta * nablaf_3)) * deltat; |
| nimbusgb | 0:6a5296aa7dbf | 148 | SEq_4 += (SEqDot_omega_4 - (beta * nablaf_4)) * deltat; |
| nimbusgb | 2:202906c5fadd | 149 | |
| nimbusgb | 0:6a5296aa7dbf | 150 | //Normalise quaternion |
| nimbusgb | 0:6a5296aa7dbf | 151 | norm = sqrt(SEq_1 * SEq_1 + SEq_2 * SEq_2 + SEq_3 * SEq_3 + SEq_4 * SEq_4); |
| nimbusgb | 0:6a5296aa7dbf | 152 | SEq_1 /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 153 | SEq_2 /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 154 | SEq_3 /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 155 | SEq_4 /= norm; |
| nimbusgb | 0:6a5296aa7dbf | 156 | |
| nimbusgb | 0:6a5296aa7dbf | 157 | if (firstUpdate == 0) { |
| nimbusgb | 0:6a5296aa7dbf | 158 | //Store orientation of auxiliary frame. |
| nimbusgb | 0:6a5296aa7dbf | 159 | AEq_1 = SEq_1; |
| nimbusgb | 0:6a5296aa7dbf | 160 | AEq_2 = SEq_2; |
| nimbusgb | 0:6a5296aa7dbf | 161 | AEq_3 = SEq_3; |
| nimbusgb | 0:6a5296aa7dbf | 162 | AEq_4 = SEq_4; |
| nimbusgb | 0:6a5296aa7dbf | 163 | firstUpdate = 1; |
| nimbusgb | 0:6a5296aa7dbf | 164 | } |
| nimbusgb | 0:6a5296aa7dbf | 165 | |
| nimbusgb | 0:6a5296aa7dbf | 166 | } |
| nimbusgb | 0:6a5296aa7dbf | 167 | |
| nimbusgb | 0:6a5296aa7dbf | 168 | void IMUfilter::computeEuler(void){ |
| nimbusgb | 0:6a5296aa7dbf | 169 | |
| nimbusgb | 0:6a5296aa7dbf | 170 | //Quaternion describing orientation of sensor relative to earth. |
| nimbusgb | 0:6a5296aa7dbf | 171 | double ESq_1, ESq_2, ESq_3, ESq_4; |
| nimbusgb | 0:6a5296aa7dbf | 172 | //Quaternion describing orientation of sensor relative to auxiliary frame. |
| nimbusgb | 0:6a5296aa7dbf | 173 | double ASq_1, ASq_2, ASq_3, ASq_4; |
| nimbusgb | 0:6a5296aa7dbf | 174 | |
| nimbusgb | 0:6a5296aa7dbf | 175 | //Compute the quaternion conjugate. |
| nimbusgb | 1:4b0e8441f099 | 176 | ESq_1 = SEq_1; |
| nimbusgb | 0:6a5296aa7dbf | 177 | ESq_2 = -SEq_2; |
| nimbusgb | 0:6a5296aa7dbf | 178 | ESq_3 = -SEq_3; |
| nimbusgb | 0:6a5296aa7dbf | 179 | ESq_4 = -SEq_4; |
| nimbusgb | 0:6a5296aa7dbf | 180 | |
| nimbusgb | 0:6a5296aa7dbf | 181 | //Compute the quaternion product. |
| nimbusgb | 0:6a5296aa7dbf | 182 | ASq_1 = ESq_1 * AEq_1 - ESq_2 * AEq_2 - ESq_3 * AEq_3 - ESq_4 * AEq_4; |
| nimbusgb | 0:6a5296aa7dbf | 183 | ASq_2 = ESq_1 * AEq_2 + ESq_2 * AEq_1 + ESq_3 * AEq_4 - ESq_4 * AEq_3; |
| nimbusgb | 0:6a5296aa7dbf | 184 | ASq_3 = ESq_1 * AEq_3 - ESq_2 * AEq_4 + ESq_3 * AEq_1 + ESq_4 * AEq_2; |
| nimbusgb | 0:6a5296aa7dbf | 185 | ASq_4 = ESq_1 * AEq_4 + ESq_2 * AEq_3 - ESq_3 * AEq_2 + ESq_4 * AEq_1; |
| nimbusgb | 0:6a5296aa7dbf | 186 | |
| nimbusgb | 0:6a5296aa7dbf | 187 | //Compute the Euler angles from the quaternion. |
| nimbusgb | 1:4b0e8441f099 | 188 | phi = atan2(2 * ASq_3 * ASq_4 - 2 * ASq_1 * ASq_2, 2 * ASq_1 * ASq_1 + 2 * ASq_4 * ASq_4 - 1); |
| nimbusgb | 1:4b0e8441f099 | 189 | theta = asin (2 * ASq_2 * ASq_3 - 2 * ASq_1 * ASq_3); |
| nimbusgb | 1:4b0e8441f099 | 190 | psi = atan2(2 * ASq_2 * ASq_3 - 2 * ASq_1 * ASq_4, 2 * ASq_1 * ASq_1 + 2 * ASq_2 * ASq_2 - 1); |
| nimbusgb | 0:6a5296aa7dbf | 191 | |
| nimbusgb | 0:6a5296aa7dbf | 192 | } |
| nimbusgb | 0:6a5296aa7dbf | 193 | |
| nimbusgb | 0:6a5296aa7dbf | 194 | double IMUfilter::getRoll(void){ |
| nimbusgb | 0:6a5296aa7dbf | 195 | |
| nimbusgb | 0:6a5296aa7dbf | 196 | return phi; |
| nimbusgb | 0:6a5296aa7dbf | 197 | |
| nimbusgb | 0:6a5296aa7dbf | 198 | } |
| nimbusgb | 0:6a5296aa7dbf | 199 | |
| nimbusgb | 0:6a5296aa7dbf | 200 | double IMUfilter::getPitch(void){ |
| nimbusgb | 0:6a5296aa7dbf | 201 | |
| nimbusgb | 0:6a5296aa7dbf | 202 | return theta; |
| nimbusgb | 0:6a5296aa7dbf | 203 | |
| nimbusgb | 0:6a5296aa7dbf | 204 | } |
| nimbusgb | 0:6a5296aa7dbf | 205 | |
| nimbusgb | 0:6a5296aa7dbf | 206 | double IMUfilter::getYaw(void){ |
| nimbusgb | 0:6a5296aa7dbf | 207 | |
| nimbusgb | 0:6a5296aa7dbf | 208 | return psi; |
| nimbusgb | 0:6a5296aa7dbf | 209 | |
| nimbusgb | 0:6a5296aa7dbf | 210 | } |
| nimbusgb | 0:6a5296aa7dbf | 211 | |
| nimbusgb | 1:4b0e8441f099 | 212 | void IMUfilter::setGyroError(double gyroscopeMeasurementError) |
| nimbusgb | 1:4b0e8441f099 | 213 | { |
| nimbusgb | 1:4b0e8441f099 | 214 | gyroMeasError = gyroscopeMeasurementError; |
| nimbusgb | 1:4b0e8441f099 | 215 | reset(); |
| nimbusgb | 1:4b0e8441f099 | 216 | } |
| nimbusgb | 1:4b0e8441f099 | 217 | |
| nimbusgb | 1:4b0e8441f099 | 218 | double IMUfilter::getGyroError(void) |
| nimbusgb | 1:4b0e8441f099 | 219 | { |
| nimbusgb | 1:4b0e8441f099 | 220 | return gyroMeasError; |
| nimbusgb | 1:4b0e8441f099 | 221 | } |
| nimbusgb | 1:4b0e8441f099 | 222 | |
| nimbusgb | 0:6a5296aa7dbf | 223 | void IMUfilter::reset(void) { |
| nimbusgb | 0:6a5296aa7dbf | 224 | |
| nimbusgb | 0:6a5296aa7dbf | 225 | firstUpdate = 0; |
| nimbusgb | 0:6a5296aa7dbf | 226 | |
| nimbusgb | 0:6a5296aa7dbf | 227 | //Quaternion orientation of earth frame relative to auxiliary frame. |
| nimbusgb | 0:6a5296aa7dbf | 228 | AEq_1 = 1; |
| nimbusgb | 0:6a5296aa7dbf | 229 | AEq_2 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 230 | AEq_3 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 231 | AEq_4 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 232 | |
| nimbusgb | 0:6a5296aa7dbf | 233 | //Estimated orientation quaternion elements with initial conditions. |
| nimbusgb | 0:6a5296aa7dbf | 234 | SEq_1 = 1; |
| nimbusgb | 0:6a5296aa7dbf | 235 | SEq_2 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 236 | SEq_3 = 0; |
| nimbusgb | 0:6a5296aa7dbf | 237 | SEq_4 = 0; |
| nimbusgb | 1:4b0e8441f099 | 238 | |
| nimbusgb | 1:4b0e8441f099 | 239 | //Compute beta. |
| nimbusgb | 1:4b0e8441f099 | 240 | beta = sqrt(3.0 / 4.0) * (PI * (gyroMeasError / 180.0)); |
| nimbusgb | 0:6a5296aa7dbf | 241 | } |