Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
[rotorcraft] add rpy/earth commands to quaternion transformations
- Loading branch information
Showing
6 changed files
with
171 additions
and
141 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
127 changes: 127 additions & 0 deletions
127
sw/airborne/firmwares/rotorcraft/stabilization/stabilization_attitude_quat_transformations.c
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,127 @@ | ||
| /* | ||
| * Copyright (C) 2013 Felix Ruess <felix.ruess@gmail.com> | ||
| * | ||
| * This file is part of paparazzi. | ||
| * | ||
| * paparazzi 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 2, or (at your option) | ||
| * any later version. | ||
| * | ||
| * paparazzi 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. | ||
| * | ||
| * You should have received a copy of the GNU General Public License | ||
| * along with paparazzi; see the file COPYING. If not, write to | ||
| * the Free Software Foundation, 59 Temple Place - Suite 330, | ||
| * Boston, MA 02111-1307, USA. | ||
| */ | ||
|
|
||
| /** @file stabilization_attitude_quat_transformations.c | ||
| * Quaternion transformation functions. | ||
| */ | ||
|
|
||
| #include "stabilization_attitude_quat_transformations.h" | ||
|
|
||
| void quat_from_rpy_cmd_i(struct Int32Quat *quat, struct Int32Eulers *rpy) { | ||
| struct FloatEulers rpy_f; | ||
| EULERS_FLOAT_OF_BFP(rpy_f, *rpy); | ||
| struct FloatQuat quat_f; | ||
| quat_from_rpy_cmd_f(&quat_f, &rpy_f); | ||
| QUAT_BFP_OF_REAL(*quat, quat_f); | ||
| } | ||
|
|
||
| void quat_from_rpy_cmd_f(struct FloatQuat *quat, struct FloatEulers *rpy) { | ||
| // only a plug for now... doesn't apply roll/pitch wrt. current yaw angle | ||
|
|
||
| /* orientation vector describing simultaneous rotation of roll/pitch/yaw */ | ||
| const struct FloatVect3 ov = {rpy->phi, rpy->theta, rpy->psi}; | ||
| /* quaternion from that orientation vector */ | ||
| FLOAT_QUAT_OF_ORIENTATION_VECT(*quat, ov); | ||
|
|
||
| } | ||
|
|
||
| void quat_from_earth_cmd_i(struct Int32Quat *quat, struct Int32Vect2 *cmd, int32_t heading) { | ||
| // use float conversion for now... | ||
| struct FloatVect2 cmd_f; | ||
| cmd_f.x = ANGLE_FLOAT_OF_BFP(cmd->x); | ||
| cmd_f.y = ANGLE_FLOAT_OF_BFP(cmd->y); | ||
| float heading_f = ANGLE_FLOAT_OF_BFP(heading); | ||
|
|
||
| struct FloatQuat quat_f; | ||
| quat_from_earth_cmd_f(&quat_f, &cmd_f, heading_f); | ||
|
|
||
| // convert back to fixed point | ||
| QUAT_BFP_OF_REAL(*quat, quat_f); | ||
| } | ||
|
|
||
| void quat_from_earth_cmd_f(struct FloatQuat *quat, struct FloatVect2 *cmd, float heading) { | ||
|
|
||
| /* orientation vector describing simultaneous rotation of roll/pitch */ | ||
| const struct FloatVect3 ov = {cmd->x, cmd->y, 0.0}; | ||
| /* quaternion from that orientation vector */ | ||
| struct FloatQuat q_rp; | ||
| FLOAT_QUAT_OF_ORIENTATION_VECT(q_rp, ov); | ||
|
|
||
| /* as rotation matrix */ | ||
| struct FloatRMat R_rp; | ||
| FLOAT_RMAT_OF_QUAT(R_rp, q_rp); | ||
| /* body x-axis (before heading command) is first column */ | ||
| struct FloatVect3 b_x; | ||
| VECT3_ASSIGN(b_x, R_rp.m[0], R_rp.m[3], R_rp.m[6]); | ||
| /* body z-axis (thrust vect) is last column */ | ||
| struct FloatVect3 thrust_vect; | ||
| VECT3_ASSIGN(thrust_vect, R_rp.m[2], R_rp.m[5], R_rp.m[8]); | ||
|
|
||
| /// @todo optimize yaw angle calculation | ||
|
|
||
| /* | ||
| * Instead of using the psi setpoint angle to rotate around the body z-axis, | ||
| * calculate the real angle needed to align the projection of the body x-axis | ||
| * onto the horizontal plane with the psi setpoint. | ||
| * | ||
| * angle between two vectors a and b: | ||
| * angle = atan2(norm(cross(a,b)), dot(a,b)) * sign(dot(cross(a,b), n)) | ||
| * where the normal n is the thrust vector (i.e. both a and b lie in that plane) | ||
| */ | ||
|
|
||
| // desired heading vect in earth x-y plane | ||
| const struct FloatVect3 psi_vect = {cosf(heading), sinf(heading), 0.0}; | ||
|
|
||
| /* projection of desired heading onto body x-y plane | ||
| * b = v - dot(v,n)*n | ||
| */ | ||
| float dot = FLOAT_VECT3_DOT_PRODUCT(psi_vect, thrust_vect); | ||
| struct FloatVect3 dotn; | ||
| FLOAT_VECT3_SMUL(dotn, thrust_vect, dot); | ||
|
|
||
| // b = v - dot(v,n)*n | ||
| struct FloatVect3 b; | ||
| FLOAT_VECT3_DIFF(b, psi_vect, dotn); | ||
| dot = FLOAT_VECT3_DOT_PRODUCT(b_x, b); | ||
| struct FloatVect3 cross; | ||
| VECT3_CROSS_PRODUCT(cross, b_x, b); | ||
| // norm of the cross product | ||
| float nc = FLOAT_VECT3_NORM(cross); | ||
| // angle = atan2(norm(cross(a,b)), dot(a,b)) | ||
| float yaw2 = atan2(nc, dot) / 2.0; | ||
|
|
||
| // negative angle if needed | ||
| // sign(dot(cross(a,b), n) | ||
| float dot_cross_ab = FLOAT_VECT3_DOT_PRODUCT(cross, thrust_vect); | ||
| if (dot_cross_ab < 0) { | ||
| yaw2 = -yaw2; | ||
| } | ||
|
|
||
| /* quaternion with yaw command */ | ||
| struct FloatQuat q_yaw; | ||
| QUAT_ASSIGN(q_yaw, cosf(yaw2), 0.0, 0.0, sinf(yaw2)); | ||
|
|
||
| /* final setpoint: apply roll/pitch, then yaw around resulting body z-axis */ | ||
| FLOAT_QUAT_COMP(*quat, q_rp, q_yaw); | ||
| FLOAT_QUAT_NORMALIZE(*quat); | ||
| FLOAT_QUAT_WRAP_SHORTEST(*quat); | ||
|
|
||
| } |
38 changes: 38 additions & 0 deletions
38
sw/airborne/firmwares/rotorcraft/stabilization/stabilization_attitude_quat_transformations.h
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,38 @@ | ||
| /* | ||
| * Copyright (C) 2013 Felix Ruess <felix.ruess@gmail.com> | ||
| * | ||
| * This file is part of paparazzi. | ||
| * | ||
| * paparazzi 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 2, or (at your option) | ||
| * any later version. | ||
| * | ||
| * paparazzi 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. | ||
| * | ||
| * You should have received a copy of the GNU General Public License | ||
| * along with paparazzi; see the file COPYING. If not, write to | ||
| * the Free Software Foundation, 59 Temple Place - Suite 330, | ||
| * Boston, MA 02111-1307, USA. | ||
| */ | ||
|
|
||
| /** @file stabilization_attitude_quat_transformations.h | ||
| * Quaternion transformation functions. | ||
| */ | ||
|
|
||
| #ifndef STABILIZATION_ATTITUDE_QUAT_TRANSFORMATIONS_H | ||
| #define STABILIZATION_ATTITUDE_QUAT_TRANSFORMATIONS_H | ||
|
|
||
| #include "math/pprz_algebra_float.h" | ||
| #include "math/pprz_algebra_int.h" | ||
|
|
||
| extern void quat_from_rpy_cmd_i(struct Int32Quat *quat, struct Int32Eulers *rpy); | ||
| extern void quat_from_rpy_cmd_f(struct FloatQuat *quat, struct FloatEulers *rpy); | ||
|
|
||
| extern void quat_from_earth_cmd_i(struct Int32Quat *quat, struct Int32Vect2 *cmd, int32_t heading); | ||
| extern void quat_from_earth_cmd_f(struct FloatQuat *quat, struct FloatVect2 *cmd, float heading); | ||
|
|
||
| #endif |