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Diffstat (limited to 'src/modules/mc_att_control_vector/mc_att_control_vector_main.cpp')
-rw-r--r-- | src/modules/mc_att_control_vector/mc_att_control_vector_main.cpp | 745 |
1 files changed, 745 insertions, 0 deletions
diff --git a/src/modules/mc_att_control_vector/mc_att_control_vector_main.cpp b/src/modules/mc_att_control_vector/mc_att_control_vector_main.cpp new file mode 100644 index 000000000..239bd5570 --- /dev/null +++ b/src/modules/mc_att_control_vector/mc_att_control_vector_main.cpp @@ -0,0 +1,745 @@ +/**************************************************************************** + * + * Copyright (c) 2013 PX4 Development Team. All rights reserved. + * Author: Tobias Naegeli <naegelit@student.ethz.ch> + * Lorenz Meier <lm@inf.ethz.ch> + * Anton Babushkin <anton.babushkin@me.com> + * + * 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_vector_main.c + * Implementation of a multicopter attitude controller based on desired rotation matrix. + * + * References + * [1] Daniel Mellinger and Vijay Kumar, "Minimum Snap Trajectory Generation and Control for Quadrotors", + * http://www.seas.upenn.edu/~dmel/mellingerICRA11.pdf + * + * @author Tobias Naegeli <naegelit@student.ethz.ch> + * @author Lorenz Meier <lm@inf.ethz.ch> + * @author Anton Babushkin <anton.babushkin@me.com> + * + */ + +#include <nuttx/config.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include <errno.h> +#include <math.h> +#include <poll.h> +#include <time.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/vehicle_rates_setpoint.h> +#include <uORB/topics/vehicle_attitude.h> +#include <uORB/topics/vehicle_control_mode.h> +#include <uORB/topics/actuator_armed.h> +#include <uORB/topics/parameter_update.h> +#include <systemlib/param/param.h> +#include <systemlib/err.h> +#include <systemlib/pid/pid.h> +#include <systemlib/perf_counter.h> +#include <systemlib/systemlib.h> +#include <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_vector_main(int argc, char *argv[]); + +#define MIN_TAKEOFF_THROTTLE 0.3f +#define YAW_DEADZONE 0.01f + +class MulticopterAttitudeControl +{ +public: + /** + * Constructor + */ + MulticopterAttitudeControl(); + + /** + * Destructor, also kills the sensors task. + */ + ~MulticopterAttitudeControl(); + + /** + * Start the sensors task. + * + * @return OK on success. + */ + int start(); + +private: + + bool _task_should_exit; /**< if true, sensor task should exit */ + int _control_task; /**< task handle for sensor task */ + + int _att_sub; /**< vehicle attitude subscription */ + int _att_sp_sub; /**< vehicle attitude setpoint */ + int _control_mode_sub; /**< vehicle control mode subscription */ + int _params_sub; /**< notification of parameter updates */ + int _manual_sub; /**< notification of manual control updates */ + int _arming_sub; /**< arming status of outputs */ + + orb_advert_t _att_sp_pub; /**< attitude setpoint publication */ + orb_advert_t _rates_sp_pub; /**< rate setpoint publication */ + orb_advert_t _actuators_0_pub; /**< actuator control group 0 setpoint */ + + struct vehicle_attitude_s _att; /**< vehicle attitude */ + struct vehicle_attitude_setpoint_s _att_sp; /**< vehicle attitude setpoint */ + struct manual_control_setpoint_s _manual; /**< r/c channel data */ + struct vehicle_control_mode_s _control_mode; /**< vehicle control mode */ + struct actuator_controls_s _actuators; /**< actuator control inputs */ + struct actuator_armed_s _arming; /**< actuator arming status */ + struct vehicle_rates_setpoint_s _rates_sp; /**< vehicle rates setpoint */ + + perf_counter_t _loop_perf; /**< loop performance counter */ + + math::Matrix<3, 3> _K; /**< diagonal gain matrix for position error */ + math::Matrix<3, 3> _K_rate_p; /**< diagonal gain matrix for angular rate error */ + math::Matrix<3, 3> _K_rate_d; /**< diagonal gain matrix for angular rate derivative */ + + math::Vector<3> _rates_prev; /**< angular rates on previous step */ + + struct { + param_t att_p; + param_t att_rate_p; + param_t att_rate_d; + param_t yaw_p; + param_t yaw_rate_p; + param_t yaw_rate_d; + } _parameter_handles; /**< handles for interesting parameters */ + + /** + * Update our local parameter cache. + */ + int parameters_update(); + + /** + * Update control outputs + */ + void control_update(); + + /** + * Check for changes in vehicle control mode. + */ + void vehicle_control_mode_poll(); + + /** + * Check for changes in manual inputs. + */ + void vehicle_manual_poll(); + + /** + * Check for set triplet updates. + */ + void vehicle_setpoint_poll(); + + /** + * Check for arming status updates. + */ + void arming_status_poll(); + + /** + * Shim for calling task_main from task_create. + */ + static void task_main_trampoline(int argc, char *argv[]); + + /** + * Main sensor collection task. + */ + void task_main() __attribute__((noreturn)); +}; + +namespace 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 */ + _att_sub(-1), + _att_sp_sub(-1), + _control_mode_sub(-1), + _params_sub(-1), + _manual_sub(-1), + _arming_sub(-1), + +/* publications */ + _att_sp_pub(-1), + _rates_sp_pub(-1), + _actuators_0_pub(-1), + +/* performance counters */ + _loop_perf(perf_alloc(PC_ELAPSED, "fw att control")) + +{ + memset(&_att, 0, sizeof(_att)); + memset(&_att_sp, 0, sizeof(_att_sp)); + memset(&_manual, 0, sizeof(_manual)); + memset(&_control_mode, 0, sizeof(_control_mode)); + memset(&_arming, 0, sizeof(_arming)); + + _K.zero(); + _K_rate_p.zero(); + _K_rate_d.zero(); + + _rates_prev.zero(); + + _parameter_handles.att_p = param_find("MC_ATT_P"); + _parameter_handles.att_rate_p = param_find("MC_ATTRATE_P"); + _parameter_handles.att_rate_d = param_find("MC_ATTRATE_D"); + _parameter_handles.yaw_p = param_find("MC_YAWPOS_P"); + _parameter_handles.yaw_rate_p = param_find("MC_YAWRATE_P"); + _parameter_handles.yaw_rate_d = param_find("MC_YAWRATE_D"); + + /* 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); + } + + att_control::g_control = nullptr; +} + +int +MulticopterAttitudeControl::parameters_update() +{ + float att_p; + float att_rate_p; + float att_rate_d; + float yaw_p; + float yaw_rate_p; + float yaw_rate_d; + + param_get(_parameter_handles.att_p, &att_p); + param_get(_parameter_handles.att_rate_p, &att_rate_p); + param_get(_parameter_handles.att_rate_d, &att_rate_d); + param_get(_parameter_handles.yaw_p, &yaw_p); + param_get(_parameter_handles.yaw_rate_p, &yaw_rate_p); + param_get(_parameter_handles.yaw_rate_d, &yaw_rate_d); + + _K(0, 0) = att_p; + _K(1, 1) = att_p; + _K(2, 2) = yaw_p; + + _K_rate_p(0, 0) = att_rate_p; + _K_rate_p(1, 1) = att_rate_p; + _K_rate_p(2, 2) = yaw_rate_p; + + _K_rate_d(0, 0) = att_rate_d; + _K_rate_d(1, 1) = att_rate_d; + _K_rate_d(2, 2) = yaw_rate_d; + + return OK; +} + +void +MulticopterAttitudeControl::vehicle_control_mode_poll() +{ + bool control_mode_updated; + + /* Check HIL state if vehicle status has changed */ + orb_check(_control_mode_sub, &control_mode_updated); + + if (control_mode_updated) { + + orb_copy(ORB_ID(vehicle_control_mode), _control_mode_sub, &_control_mode); + } +} + +void +MulticopterAttitudeControl::vehicle_manual_poll() +{ + bool manual_updated; + + /* get pilots inputs */ + orb_check(_manual_sub, &manual_updated); + + if (manual_updated) { + + orb_copy(ORB_ID(manual_control_setpoint), _manual_sub, &_manual); + } +} + +void +MulticopterAttitudeControl::vehicle_setpoint_poll() +{ + /* check if there is a new setpoint */ + bool att_sp_updated; + orb_check(_att_sp_sub, &att_sp_updated); + + if (att_sp_updated) { + orb_copy(ORB_ID(vehicle_attitude_setpoint), _att_sp_sub, &_att_sp); + } +} + +void +MulticopterAttitudeControl::arming_status_poll() +{ + /* check if there is a new setpoint */ + bool arming_updated; + orb_check(_arming_sub, &arming_updated); + + if (arming_updated) { + orb_copy(ORB_ID(actuator_armed), _arming_sub, &_arming); + } +} + +void +MulticopterAttitudeControl::task_main_trampoline(int argc, char *argv[]) +{ + att_control::g_control->task_main(); +} + +void +MulticopterAttitudeControl::task_main() +{ + /* inform about start */ + warnx("started"); + fflush(stdout); + + /* + * do subscriptions + */ + _att_sp_sub = orb_subscribe(ORB_ID(vehicle_attitude_setpoint)); + _att_sub = orb_subscribe(ORB_ID(vehicle_attitude)); + _control_mode_sub = orb_subscribe(ORB_ID(vehicle_control_mode)); + _params_sub = orb_subscribe(ORB_ID(parameter_update)); + _manual_sub = orb_subscribe(ORB_ID(manual_control_setpoint)); + _arming_sub = orb_subscribe(ORB_ID(actuator_armed)); + + /* rate limit attitude updates to 100Hz */ + orb_set_interval(_att_sub, 10); + + parameters_update(); + + /* initialize values of critical structs until first regular update */ + _arming.armed = false; + + /* get an initial update for all sensor and status data */ + vehicle_setpoint_poll(); + vehicle_control_mode_poll(); + vehicle_manual_poll(); + arming_status_poll(); + + /* setpoint rotation matrix */ + math::Matrix<3, 3> R_sp; + R_sp.identity(); + + /* rotation matrix for current state */ + math::Matrix<3, 3> R; + R.identity(); + + /* current angular rates */ + math::Vector<3> rates; + rates.zero(); + + /* identity matrix */ + math::Matrix<3, 3> I; + I.identity(); + + math::Quaternion q; + + bool reset_yaw_sp = true; + + /* wakeup source(s) */ + struct pollfd fds[2]; + + /* Setup of loop */ + fds[0].fd = _params_sub; + fds[0].events = POLLIN; + fds[1].fd = _att_sub; + fds[1].events = POLLIN; + + while (!_task_should_exit) { + + /* wait for up to 500ms for data */ + int pret = poll(&fds[0], (sizeof(fds) / sizeof(fds[0])), 100); + + /* timed out - periodic check for _task_should_exit, etc. */ + 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); + continue; + } + + perf_begin(_loop_perf); + + /* only update parameters if they changed */ + if (fds[0].revents & POLLIN) { + /* copy the topic to clear updated flag */ + struct parameter_update_s update; + orb_copy(ORB_ID(parameter_update), _params_sub, &update); + + parameters_update(); + } + + /* only run controller if attitude changed */ + if (fds[1].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 large dt's */ + if (dt > 0.02f) + dt = 0.02f; + + /* copy attitude topic */ + orb_copy(ORB_ID(vehicle_attitude), _att_sub, &_att); + + vehicle_setpoint_poll(); + vehicle_control_mode_poll(); + arming_status_poll(); + vehicle_manual_poll(); + + float yaw_sp_move_rate = 0.0f; + bool publish_att_sp = false; + + /* define which input is the dominating control input */ + if (_control_mode.flag_control_manual_enabled) { + /* manual input */ + if (!_control_mode.flag_control_climb_rate_enabled) { + /* pass throttle directly if not in altitude control mode */ + _att_sp.thrust = _manual.throttle; + } + + if (!_arming.armed) { + /* reset yaw setpoint when disarmed */ + reset_yaw_sp = true; + } + + if (_control_mode.flag_control_attitude_enabled) { + /* control attitude, update attitude setpoint depending on mode */ + + if (_att_sp.thrust < 0.1f) { + // TODO + //if (_status.condition_landed) { + /* reset yaw setpoint if on ground */ + // reset_yaw_sp = true; + //} + } else { + if (_manual.yaw < -YAW_DEADZONE || YAW_DEADZONE < _manual.yaw) { + /* move yaw setpoint */ + yaw_sp_move_rate = _manual.yaw; + _att_sp.yaw_body = _wrap_pi(_att_sp.yaw_body + yaw_sp_move_rate * dt); + _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; + _att_sp.yaw_body = _att.yaw; + _att_sp.R_valid = false; + publish_att_sp = true; + } + + if (!_control_mode.flag_control_velocity_enabled) { + /* update attitude setpoint if not in position control mode */ + _att_sp.roll_body = _manual.roll; + _att_sp.pitch_body = _manual.pitch; + _att_sp.R_valid = false; + publish_att_sp = true; + } + + } else { + /* manual rate inputs (ACRO) */ + // TODO + /* reset yaw setpoint after ACRO */ + reset_yaw_sp = true; + } + + } else { + /* reset yaw setpoint after non-manual control */ + reset_yaw_sp = true; + } + + if (_att_sp.R_valid) { + /* rotation matrix in _att_sp is valid, use it */ + R_sp.set(&_att_sp.R_body[0][0]); + + } else { + /* rotation matrix in _att_sp is not valid, use euler angles instead */ + R_sp.from_euler(_att_sp.roll_body, _att_sp.pitch_body, _att_sp.yaw_body); + + /* copy rotation matrix back to setpoint struct */ + memcpy(&_att_sp.R_body[0][0], &R_sp.data[0][0], sizeof(_att_sp.R_body)); + _att_sp.R_valid = true; + } + + if (publish_att_sp) { + /* publish the attitude setpoint */ + _att_sp.timestamp = hrt_absolute_time(); + + if (_att_sp_pub > 0) { + orb_publish(ORB_ID(vehicle_attitude_setpoint), _att_sp_pub, &_att_sp); + + } else { + _att_sp_pub = orb_advertise(ORB_ID(vehicle_attitude_setpoint), &_att_sp); + } + } + + /* rotation matrix for current state */ + R.set(_att.R); + + /* current body angular rates */ + rates(0) = _att.rollspeed; + rates(1) = _att.pitchspeed; + rates(2) = _att.yawspeed; + + /* 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 */ + 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; + } + + /* angular rates setpoint*/ + math::Vector<3> rates_sp = _K * e_R; + + /* feed forward yaw setpoint rate */ + rates_sp(2) += yaw_sp_move_rate * yaw_w; + math::Vector<3> control = _K_rate_p * (rates_sp - rates) + _K_rate_d * (_rates_prev - rates) / fmaxf(dt, 0.003f); + _rates_prev = rates; + + /* publish the attitude rates setpoint */ + _rates_sp.roll = rates_sp(0); + _rates_sp.pitch = rates_sp(1); + _rates_sp.yaw = rates_sp(2); + _rates_sp.thrust = _att_sp.thrust; + _rates_sp.timestamp = hrt_absolute_time(); + + if (_rates_sp_pub > 0) { + orb_publish(ORB_ID(vehicle_rates_setpoint), _rates_sp_pub, &_rates_sp); + + } else { + _rates_sp_pub = orb_advertise(ORB_ID(vehicle_rates_setpoint), &_rates_sp); + } + + /* publish the attitude controls */ + if (_control_mode.flag_control_rates_enabled) { + _actuators.control[0] = (isfinite(control(0))) ? control(0) : 0.0f; + _actuators.control[1] = (isfinite(control(1))) ? control(1) : 0.0f; + _actuators.control[2] = (isfinite(control(2))) ? control(2) : 0.0f; + _actuators.control[3] = (isfinite(_rates_sp.thrust)) ? _rates_sp.thrust : 0.0f; + _actuators.timestamp = hrt_absolute_time(); + } else { + /* controller disabled, publish zero attitude controls */ + _actuators.control[0] = 0.0f; + _actuators.control[1] = 0.0f; + _actuators.control[2] = 0.0f; + _actuators.control[3] = 0.0f; + _actuators.timestamp = hrt_absolute_time(); + } + + if (_actuators_0_pub > 0) { + /* publish the attitude setpoint */ + orb_publish(ORB_ID(actuator_controls_0), _actuators_0_pub, &_actuators); + + } else { + /* advertise and publish */ + _actuators_0_pub = orb_advertise(ORB_ID(actuator_controls_0), &_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_vector", + SCHED_DEFAULT, + SCHED_PRIORITY_MAX - 5, + 2048, + (main_t)&MulticopterAttitudeControl::task_main_trampoline, + nullptr); + + if (_control_task < 0) { + warn("task start failed"); + return -errno; + } + + return OK; +} + +int mc_att_control_vector_main(int argc, char *argv[]) +{ + if (argc < 1) + errx(1, "usage: mc_att_control_vector {start|stop|status}"); + + if (!strcmp(argv[1], "start")) { + + if (att_control::g_control != nullptr) + errx(1, "already running"); + + att_control::g_control = new MulticopterAttitudeControl; + + if (att_control::g_control == nullptr) + errx(1, "alloc failed"); + + if (OK != att_control::g_control->start()) { + delete att_control::g_control; + att_control::g_control = nullptr; + err(1, "start failed"); + } + + exit(0); + } + + if (!strcmp(argv[1], "stop")) { + if (att_control::g_control == nullptr) + errx(1, "not running"); + + delete att_control::g_control; + att_control::g_control = nullptr; + exit(0); + } + + if (!strcmp(argv[1], "status")) { + if (att_control::g_control) { + errx(0, "running"); + + } else { + errx(1, "not running"); + } + } + + warnx("unrecognized command"); + return 1; +} |