control_toolbox: sinusoid.cpp Source File

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00034 
00037 #include "control_toolbox/sinusoid.h"
00038 #include <cmath>
00039 #include <iostream>
00040 
00041 using namespace std;
00042 
00043 namespace control_toolbox
00044 {
00045 
00046 Sinusoid::Sinusoid(double offset, double amplitude, double frequency, double phase):
00047   offset_(offset),
00048   amplitude_(amplitude),
00049   frequency_(frequency),
00050   phase_(phase)
00051 {
00052 }
00053 
00054 bool Sinusoid::initXml(TiXmlElement *ti_xml_element)
00055 {
00056   const char* attr;
00057   attr = ti_xml_element->Attribute("offset");
00058   offset_ = attr ? atof(attr) : 0.0;
00059   attr = ti_xml_element->Attribute("amplitude");
00060   amplitude_ = attr ? atof(attr) : 0.0;
00061   attr = ti_xml_element->Attribute("frequency");
00062   frequency_ = attr ? atof(attr) : 0.0;
00063   attr = ti_xml_element->Attribute("phase");
00064   phase_ = attr ? atof(attr) : 0.0;
00065   return true; // does not fail for now, we assume a default of 0 for all params
00066 }
00067 
00068 Sinusoid::~Sinusoid()
00069 {
00070 }
00071 
00072 Sinusoid::Sinusoid()
00073 {
00074 }
00075 
00076 double Sinusoid::update(double time, double& qd, double& qdd)
00077 {
00078   double angular_frequency = 2.0*M_PI*frequency_;
00079   double p = phase_ + angular_frequency*time;
00080   double sin_p = sin(p);
00081   double cos_p = cos(p);
00082   double q = offset_ + amplitude_*sin_p;
00083   qd = angular_frequency*amplitude_*cos_p;
00084   qdd = -angular_frequency*angular_frequency*amplitude_*sin_p;
00085   return q;
00086 }
00087 
00088 void Sinusoid::debug()
00089 {
00090   cout << "offset=" << offset_ << " amplitude=" << amplitude_ << " phase=" << phase_ << " frequency=" << frequency_ << endl;
00091 }
00092 
00093 } // namespace control_toolbox