diff options
Diffstat (limited to 'src/platforms/ros/nodes/mc_mixer/mc_mixer.cpp')
-rw-r--r-- | src/platforms/ros/nodes/mc_mixer/mc_mixer.cpp | 276 |
1 files changed, 276 insertions, 0 deletions
diff --git a/src/platforms/ros/nodes/mc_mixer/mc_mixer.cpp b/src/platforms/ros/nodes/mc_mixer/mc_mixer.cpp new file mode 100644 index 000000000..54f5fa78b --- /dev/null +++ b/src/platforms/ros/nodes/mc_mixer/mc_mixer.cpp @@ -0,0 +1,276 @@ +/**************************************************************************** + * + * Copyright (c) 2014 PX4 Development Team. All rights reserved. + * + * 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_mixer.cpp + * Dummy multicopter mixer for euroc simulator (gazebo) + * + * @author Roman Bapst <romanbapst@yahoo.de> +*/ +#include <ros/ros.h> +#include <px4.h> +#include <lib/mathlib/mathlib.h> +#include <mav_msgs/MotorSpeed.h> +#include <string> + +class MultirotorMixer +{ +public: + + MultirotorMixer(); + + struct Rotor { + float roll_scale; + float pitch_scale; + float yaw_scale; + }; + + void actuatorControlsCallback(const PX4_TOPIC_T(actuator_controls_0) &msg); + void actuatorArmedCallback(const PX4_TOPIC_T(actuator_armed) &msg); + +private: + + ros::NodeHandle _n; + ros::Subscriber _sub; + ros::Publisher _pub; + + const Rotor *_rotors; + + unsigned _rotor_count; + + struct { + float control[8]; + } inputs; + + struct { + float control[8]; + } outputs; + + bool _armed; + ros::Subscriber _sub_actuator_armed; + + void mix(); +}; + +const MultirotorMixer::Rotor _config_x[] = { + { -0.707107, 0.707107, 1.00 }, + { 0.707107, -0.707107, 1.00 }, + { 0.707107, 0.707107, -1.00 }, + { -0.707107, -0.707107, -1.00 }, +}; + +const MultirotorMixer::Rotor _config_quad_plus[] = { + { -1.000000, 0.000000, 1.00 }, + { 1.000000, 0.000000, 1.00 }, + { 0.000000, 1.000000, -1.00 }, + { -0.000000, -1.000000, -1.00 }, +}; + +const MultirotorMixer::Rotor _config_quad_plus_euroc[] = { + { 0.000000, 1.000000, 1.00 }, + { -0.000000, -1.000000, 1.00 }, + { 1.000000, 0.000000, -1.00 }, + { -1.000000, 0.000000, -1.00 }, +}; +const MultirotorMixer::Rotor _config_quad_wide[] = { + { -0.927184, 0.374607, 1.000000 }, + { 0.777146, -0.629320, 1.000000 }, + { 0.927184, 0.374607, -1.000000 }, + { -0.777146, -0.629320, -1.000000 }, +}; +const MultirotorMixer::Rotor _config_quad_iris[] = { + { -0.876559, 0.481295, 1.000000 }, + { 0.826590, -0.562805, 1.000000 }, + { 0.876559, 0.481295, -1.000000 }, + { -0.826590, -0.562805, -1.000000 }, +}; + +const MultirotorMixer::Rotor *_config_index[5] = { + &_config_x[0], + &_config_quad_plus[0], + &_config_quad_plus_euroc[0], + &_config_quad_wide[0], + &_config_quad_iris[0] +}; + +MultirotorMixer::MultirotorMixer(): + _n(), + _rotor_count(4), + _rotors(_config_index[0]) +{ + _sub = _n.subscribe("actuator_controls_0", 1, &MultirotorMixer::actuatorControlsCallback, this); + _pub = _n.advertise<mav_msgs::MotorSpeed>("/mixed_motor_commands", 10); + + if (!_n.hasParam("motor_scaling_radps")) { + _n.setParam("motor_scaling_radps", 150.0); + } + + if (!_n.hasParam("motor_offset_radps")) { + _n.setParam("motor_offset_radps", 600.0); + } + + if (!_n.hasParam("mixer")) { + _n.setParam("mixer", "x"); + } + + _sub_actuator_armed = _n.subscribe("actuator_armed", 1, &MultirotorMixer::actuatorArmedCallback, this); +} + +void MultirotorMixer::mix() +{ + float roll = math::constrain(inputs.control[0], -1.0f, 1.0f); + float pitch = math::constrain(inputs.control[1], -1.0f, 1.0f); + float yaw = math::constrain(inputs.control[2], -1.0f, 1.0f); + float thrust = math::constrain(inputs.control[3], 0.0f, 1.0f); + float min_out = 0.0f; + float max_out = 0.0f; + + /* perform initial mix pass yielding unbounded outputs, ignore yaw */ + for (unsigned i = 0; i < _rotor_count; i++) { + float out = roll * _rotors[i].roll_scale + + pitch * _rotors[i].pitch_scale + thrust; + + /* limit yaw if it causes outputs clipping */ + if (out >= 0.0f && out < -yaw * _rotors[i].yaw_scale) { + yaw = -out / _rotors[i].yaw_scale; + } + + /* calculate min and max output values */ + if (out < min_out) { + min_out = out; + } + + if (out > max_out) { + max_out = out; + } + + outputs.control[i] = out; + } + + /* scale down roll/pitch controls if some outputs are negative, don't add yaw, keep total thrust */ + if (min_out < 0.0f) { + float scale_in = thrust / (thrust - min_out); + + /* mix again with adjusted controls */ + for (unsigned i = 0; i < _rotor_count; i++) { + outputs.control[i] = scale_in + * (roll * _rotors[i].roll_scale + + pitch * _rotors[i].pitch_scale) + thrust; + } + + } else { + /* roll/pitch mixed without limiting, add yaw control */ + for (unsigned i = 0; i < _rotor_count; i++) { + outputs.control[i] += yaw * _rotors[i].yaw_scale; + } + } + + /* scale down all outputs if some outputs are too large, reduce total thrust */ + float scale_out; + + if (max_out > 1.0f) { + scale_out = 1.0f / max_out; + + } else { + scale_out = 1.0f; + } + + /* scale outputs to range _idle_speed..1, and do final limiting */ + for (unsigned i = 0; i < _rotor_count; i++) { + outputs.control[i] = math::constrain(outputs.control[i], 0.0f, 1.0f); + } +} + +void MultirotorMixer::actuatorControlsCallback(const PX4_TOPIC_T(actuator_controls_0) &msg) +{ + // read message + for (int i = 0; i < msg.NUM_ACTUATOR_CONTROLS; i++) { + inputs.control[i] = msg.control[i]; + } + + // switch mixer if necessary + std::string mixer_name; + _n.getParamCached("mixer", mixer_name); + if (mixer_name == "x") { + _rotors = _config_index[0]; + ROS_WARN("using x"); + } else if (mixer_name == "+") { + _rotors = _config_index[1]; + } else if (mixer_name == "e") { + _rotors = _config_index[2]; + } else if (mixer_name == "w") { + _rotors = _config_index[3]; + ROS_WARN("using w"); + } else if (mixer_name == "i") { + _rotors = _config_index[4]; + ROS_WARN("using i"); + } + ROS_WARN("mixer_name %s", mixer_name.c_str()); + + // mix + mix(); + + // publish message + mav_msgs::MotorSpeed rotor_vel_msg; + double scaling; + double offset; + _n.getParamCached("motor_scaling_radps", scaling); + _n.getParamCached("motor_offset_radps", offset); + + if (_armed) { + for (int i = 0; i < _rotor_count; i++) { + rotor_vel_msg.motor_speed.push_back(outputs.control[i] * scaling + offset); + } + + } else { + for (int i = 0; i < _rotor_count; i++) { + rotor_vel_msg.motor_speed.push_back(0.0); + } + } + + _pub.publish(rotor_vel_msg); +} + +int main(int argc, char **argv) +{ + ros::init(argc, argv, "mc_mixer"); + MultirotorMixer mixer; + ros::spin(); + + return 0; +} + +void MultirotorMixer::actuatorArmedCallback(const PX4_TOPIC_T(actuator_armed) &msg) +{ + _armed = msg.armed; +} |