sinusoid.cpp

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#include "control_toolbox/sinusoid.h"
#include <cmath>
#include <iostream>

using namespace std;

namespace control_toolbox
{

Sinusoid::Sinusoid(double offset, double amplitude, double frequency, double phase):
  offset_(offset),
  amplitude_(amplitude),
  frequency_(frequency),
  phase_(phase)
{
}

bool Sinusoid::initXml(TiXmlElement *ti_xml_element)
{
  const char* attr;
  attr = ti_xml_element->Attribute("offset");
  offset_ = attr ? atof(attr) : 0.0;
  attr = ti_xml_element->Attribute("amplitude");
  amplitude_ = attr ? atof(attr) : 0.0;
  attr = ti_xml_element->Attribute("frequency");
  frequency_ = attr ? atof(attr) : 0.0;
  attr = ti_xml_element->Attribute("phase");
  phase_ = attr ? atof(attr) : 0.0;
  return true; // does not fail for now, we assume a default of 0 for all params
}

Sinusoid::~Sinusoid()
{
}

Sinusoid::Sinusoid()
{
}

double Sinusoid::update(double time, double& qd, double& qdd)
{
  double angular_frequency = 2.0*M_PI*frequency_;
  double p = phase_ + angular_frequency*time;
  double sin_p = sin(p);
  double cos_p = cos(p);
  double q = offset_ + amplitude_*sin_p;
  qd = angular_frequency*amplitude_*cos_p;
  qdd = -angular_frequency*angular_frequency*amplitude_*sin_p;
  return q;
}

void Sinusoid::debug()
{
  cout << "offset=" << offset_ << " amplitude=" << amplitude_ << " phase=" << phase_ << " frequency=" << frequency_ << endl;
}

} // namespace control_toolbox