void
HeadingIndicator::init ()
{
- _serviceable_node =
- fgGetNode("/instrumentation/heading-indicator/serviceable", true);
- _spin_node =
- fgGetNode("/instrumentation/heading-indicator/spin", true);
_offset_node =
fgGetNode("/instrumentation/heading-indicator/offset-deg", true);
_heading_in_node = fgGetNode("/orientation/heading-deg", true);
void
HeadingIndicator::bind ()
{
+ fgTie("/instrumentation/heading-indicator/serviceable",
+ &_gyro, &Gyro::is_serviceable, &Gyro::set_serviceable);
+ fgTie("/instrumentation/heading-indicator/spin",
+ &_gyro, &Gyro::get_spin_norm, &Gyro::set_spin_norm);
}
void
HeadingIndicator::unbind ()
{
+ fgUntie("/instrumentation/heading-indicator/serviceable");
+ fgUntie("/instrumentation/heading-indicator/spin");
}
void
HeadingIndicator::update (double dt)
{
- // First, calculate the bogo-spin from 0 to 1.
- // All numbers are made up.
-
- double spin = _spin_node->getDoubleValue();
- spin -= 0.005 * dt; // spin decays every 0.5% every second.
-
- // spin increases up to 25% every second
- // if suction is available and the gauge
- // is serviceable.
- if (_serviceable_node->getBoolValue()) {
- double suction = _suction_node->getDoubleValue();
- double step = 0.25 * (suction / 5.0) * dt;
- if ((spin + step) <= (suction / 5.0))
- spin += step;
- }
- if (spin > 1.0)
- spin = 1.0;
- else if (spin < 0.0)
- spin = 0.0;
- _spin_node->setDoubleValue(spin);
+ // Get the spin from the gyro
+ _gyro.set_power_norm(_suction_node->getDoubleValue()/5.0);
+ _gyro.update(dt);
+ double spin = _gyro.get_spin_norm();
// Next, calculate time-based precession
double offset = _offset_node->getDoubleValue();
// introducing errors.
double factor = 0.01 / (spin * spin * spin * spin * spin * spin);
double heading = _heading_in_node->getDoubleValue();
+
+ // Now, we have to get the current
+ // heading and the last heading into
+ // the same range.
+ while ((heading - _last_heading_deg) > 180)
+ _last_heading_deg += 360;
+ while ((heading - _last_heading_deg) < -180)
+ _last_heading_deg -= 360;
+
heading = fgGetLowPass(_last_heading_deg, heading, dt/factor);
_last_heading_deg = heading;