1
0
Fork 0
flightgear/src/Instrumentation/turn_indicator.cxx
mfranz b9e4775a7a Roy Vegard Ovesen:
- finish cleanup/optimization of instrumentation system (started by mfranz)
- improve configuration of special properties by
  addressing them directly
2006-12-06 22:11:43 +00:00

101 lines
2.7 KiB
C++

// turn_indicator.cxx - an electric-powered turn indicator.
// Written by David Megginson, started 2003.
//
// This file is in the Public Domain and comes with no warranty.
#include <simgear/compiler.h>
#include STL_IOSTREAM
#include STL_STRING
#include <sstream>
#include "turn_indicator.hxx"
#include <Main/fg_props.hxx>
#include <Main/util.hxx>
// Use a bigger number to be more responsive, or a smaller number
// to be more sluggish.
#define RESPONSIVENESS 0.5
TurnIndicator::TurnIndicator ( SGPropertyNode *node) :
_last_rate(0),
_name(node->getStringValue("name", "turn-indicator")),
_num(node->getIntValue("number", 0))
{
}
TurnIndicator::~TurnIndicator ()
{
}
void
TurnIndicator::init ()
{
string branch;
branch = "/instrumentation/" + _name;
SGPropertyNode *node = fgGetNode(branch.c_str(), _num, true );
_roll_rate_node = fgGetNode("/orientation/roll-rate-degps", true);
_yaw_rate_node = fgGetNode("/orientation/yaw-rate-degps", true);
_electric_current_node =
fgGetNode("/systems/electrical/outputs/turn-coordinator", true);
_rate_out_node = node->getChild("indicated-turn-rate", 0, true);
}
void
TurnIndicator::bind ()
{
std::ostringstream temp;
string branch;
temp << _num;
branch = "/instrumentation/" + _name + "[" + temp.str() + "]";
fgTie((branch + "/serviceable").c_str(),
&_gyro, &Gyro::is_serviceable, &Gyro::set_serviceable);
fgTie((branch + "/spin").c_str(),
&_gyro, &Gyro::get_spin_norm, &Gyro::set_spin_norm);
}
void
TurnIndicator::unbind ()
{
std::ostringstream temp;
string branch;
temp << _num;
branch = "/instrumentation/" + _name + "[" + temp.str() + "]";
fgUntie((branch + "/serviceable").c_str());
fgUntie((branch + "/serviceable").c_str());
}
void
TurnIndicator::update (double dt)
{
// Get the spin from the gyro
double power = _electric_current_node->getDoubleValue() / 12.0;
_gyro.set_power_norm(power);
_gyro.update(dt);
double spin = _gyro.get_spin_norm();
// Calculate the indicated rate
double factor = 1.0 - ((1.0 - spin) * (1.0 - spin) * (1.0 - spin));
double rate = ((_roll_rate_node->getDoubleValue() / 20.0) +
(_yaw_rate_node->getDoubleValue() / 3.0));
// Clamp the rate
if (rate < -2.5)
rate = -2.5;
else if (rate > 2.5)
rate = 2.5;
// Lag left, based on gyro spin
rate = -2.5 + (factor * (rate + 2.5));
rate = fgGetLowPass(_last_rate, rate, dt*RESPONSIVENESS);
_last_rate = rate;
// Publish the indicated rate
_rate_out_node->setDoubleValue(rate);
}
// end of turn_indicator.cxx