multirotor_forces_and_moments.h

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/*
 * Copyright (c) 2017 Daniel Koch, James Jackson and Gary Ellingson, BYU MAGICC Lab.
 * All rights reserved.
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 * modification, are permitted provided that the following conditions are met:
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 *   list of conditions and the following disclaimer.
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 *   this software without specific prior written permission.
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#ifndef ROSFLIGHT_SIM_MULTIROTOR_FORCES_AND_MOMENTS_H
#define ROSFLIGHT_SIM_MULTIROTOR_FORCES_AND_MOMENTS_H

#include <ros/ros.h>
#include <eigen3/Eigen/Dense>

#include <rosflight_sim/mav_forces_and_moments.h>

namespace rosflight_sim
{
class Multirotor : public MAVForcesAndMoments
{
private:
  ros::NodeHandle* nh_;
  Eigen::Vector3d wind_;

  double prev_time_;

  struct Rotor
  {
    double max;
    std::vector<double> F_poly;
    std::vector<double> T_poly;
    double tau_up; // time constants for response
    double tau_down;
  };

  struct Motor
  {
    Rotor rotor;
    Eigen::Vector3d position;
    Eigen::Vector3d normal;
    int direction; // 1 for CW -1 for CCW
  };

  int num_rotors_;
  std::vector<Motor> motors_;

  double linear_mu_;
  double angular_mu_;
  std::vector<double> ground_effect_;

  double mass_;

  // Container for an Actuator
  struct Actuator
  {
    double max;
    double tau_up;
    double tau_down;
  };

  // Struct of Actuators
  // This organizes the physical limitations of the abstract torques and Force
  struct Actuators
  {
    Actuator l;
    Actuator m;
    Actuator n;
    Actuator F;
  } actuators_;

  Eigen::MatrixXd rotor_position_;
  Eigen::MatrixXd rotor_plane_normal_;
  Eigen::VectorXd rotor_rotation_direction_;

  Eigen::MatrixXd force_allocation_matrix_;
  Eigen::MatrixXd torque_allocation_matrix_;
  Eigen::VectorXd desired_forces_;
  Eigen::VectorXd desired_torques_;
  Eigen::VectorXd actual_forces_;
  Eigen::VectorXd actual_torques_;

public:
  Multirotor(ros::NodeHandle* nh);
  ~Multirotor();

  Eigen::Matrix<double, 6, 1> updateForcesAndTorques(Current_State x, const int act_cmds[]);
  void set_wind(Eigen::Vector3d wind);
};

} // namespace rosflight_sim

#endif // ROSFLIGHT_SIM_MULTIROTOR_FORCES_AND_MOMENTS_H