odometry.cpp

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/*
 * Author: Luca Marchionni
 * Author: Bence Magyar
 * Author: Enrique Fernández
 * Author: Paul Mathieu
 */

#include <double_diff_drive_controller/odometry.h>

#include <tf/transform_datatypes.h>

#include <boost/bind.hpp>

namespace double_diff_drive_controller
{

namespace bacc = boost::accumulators;

Odometry::Odometry(size_t velocity_rolling_window_size)
: timestamp_(0.0)
, x_(0.0)
, y_(0.0)
, heading_(0.0)
, linear_(0.0)
, angular_(0.0)
, wheel_radius_(0.0)
, wheel_separation_(0.0)
, velocity_rolling_window_size_(velocity_rolling_window_size)
, linear_acc_(RollingWindow::window_size = velocity_rolling_window_size)
, angular_acc_(RollingWindow::window_size = velocity_rolling_window_size)
, integrate_fun_(boost::bind(&Odometry::integrateExact, this, _1, _2))
{
}

void Odometry::init(const ros::Time& time)
{
  // Reset accumulators:
  linear_acc_ = RollingMeanAcc(RollingWindow::window_size = velocity_rolling_window_size_);
  angular_acc_ = RollingMeanAcc(RollingWindow::window_size = velocity_rolling_window_size_);

  // Reset timestamp:
  timestamp_ = time;
}

bool Odometry::update(double drive_motor_vel, double steer_motor_vel, const ros::Time &time)
{
  const double dt = (time - timestamp_).toSec();
  if (dt < 0.0001)
    return false; // Interval too small to integrate with

  timestamp_ = time;

  linear_ = wheel_radius_ * (1 / drive_motor_gear_ratio_) * drive_motor_vel;
  angular_ = (1 / steer_motor_gear_ratio_) * steer_motor_vel * (wheel_separation_ / 2.0) * wheel_radius_;

  integrate_fun_(linear_ * dt, angular_ * dt);

  return true;
}

void Odometry::updateOpenLoop(double linear, double angular, const ros::Time &time)
{
  linear_ = linear;
  angular_ = angular;

  const double dt = (time - timestamp_).toSec();
  timestamp_ = time;
  integrate_fun_(linear * dt, angular * dt);
}

void Odometry::setWheelsParams(double wheel_radius, double wheel_separation)
{
  wheel_radius_ = wheel_radius;
  wheel_separation_ = wheel_separation;
}


void Odometry::setGearRatios(double drive_motor_gear_ratio, double steer_motor_gear_ratio)
{
  drive_motor_gear_ratio_ = drive_motor_gear_ratio;
  steer_motor_gear_ratio_ = steer_motor_gear_ratio;
}

void Odometry::integrateExact(double linear, double angular)
{
  heading_ += angular;

  tf::Matrix3x3 R_m_odom = tf::Matrix3x3(tf::createQuaternionFromYaw(heading_));
  tf::Vector3 vel_inOdom = R_m_odom * tf::Vector3(linear, 0.0, 0.0);

  x_ += vel_inOdom.x();
  y_ += vel_inOdom.y();
}

} // namespace double_diff_drive_controller