// TODO:
// - better spin-up
+#include <simgear/compiler.h>
+
+#include STL_IOSTREAM
+#include STL_STRING
+#include <sstream>
+
+#include <math.h> // fabs()
+
#include "attitude_indicator.hxx"
#include <Main/fg_props.hxx>
#include <Main/util.hxx>
+AttitudeIndicator::AttitudeIndicator ( SGPropertyNode *node )
+ :
+ name("attitude-indicator"),
+ num(0),
+ vacuum_system("/systems/vacuum")
+{
+ int i;
+ for ( i = 0; i < node->nChildren(); ++i ) {
+ SGPropertyNode *child = node->getChild(i);
+ string cname = child->getName();
+ string cval = child->getStringValue();
+ if ( cname == "name" ) {
+ name = cval;
+ } else if ( cname == "number" ) {
+ num = (int) child->getDoubleValue();
+ } else if ( cname == "vacuum-system" ) {
+ vacuum_system = cval;
+ } else {
+ SG_LOG( SG_INSTR, SG_WARN, "Error in attitude-indicator config logic" );
+ if ( name.length() ) {
+ SG_LOG( SG_INSTR, SG_WARN, "Section = " << name );
+ }
+ }
+ }
+}
+
AttitudeIndicator::AttitudeIndicator ()
- : _tumble(0)
{
}
void
AttitudeIndicator::init ()
{
- // TODO: allow index of pump and AI
- // to be configured.
+ string branch;
+ branch = "/instrumentation/" + name;
+ vacuum_system += "/suction-inhg";
+
+ SGPropertyNode *node = fgGetNode(branch.c_str(), num, true );
+
_pitch_in_node = fgGetNode("/orientation/pitch-deg", true);
_roll_in_node = fgGetNode("/orientation/roll-deg", true);
- _suction_node = fgGetNode("/systems/vacuum[0]/suction-inhg", true);
- _tumble_flag_node =
- fgGetNode("/instrumentation/attitude-indicator/config/tumble-flag",
- true);
- _pitch_out_node =
- fgGetNode("/instrumentation/attitude-indicator/indicated-pitch-deg",
- true);
- _roll_out_node =
- fgGetNode("/instrumentation/attitude-indicator/indicated-roll-deg",
- true);
+ _suction_node = fgGetNode(vacuum_system.c_str(), true);
+ SGPropertyNode *cnode = node->getChild("config", 0, true);
+ _tumble_flag_node = cnode->getChild("tumble-flag", 0, true);
+ _caged_node = node->getChild("caged-flag", 0, true);
+ _tumble_node = node->getChild("tumble-norm", 0, true);
+ _pitch_int_node = node->getChild("internal-pitch-deg", 0, true);
+ _roll_int_node = node->getChild("internal-roll-deg", 0, true);
+ _pitch_out_node = node->getChild("indicated-pitch-deg", 0, true);
+ _roll_out_node = node->getChild("indicated-roll-deg", 0, true);
}
void
AttitudeIndicator::bind ()
{
- fgTie("/instrumentation/attitude-indicator/serviceable",
+ 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("/instrumentation/attitude-indicator/spin",
+ fgTie((branch + "/spin").c_str(),
&_gyro, &Gyro::get_spin_norm, &Gyro::set_spin_norm);
}
void
AttitudeIndicator::unbind ()
{
- fgUntie("/instrumentation/attitude-indicator/serviceable");
- fgUntie("/instrumentation/attitude-indicator/spin");
+ std::ostringstream temp;
+ string branch;
+ temp << num;
+ branch = "/instrumentation/" + name + "[" + temp.str() + "]";
+
+ fgUntie((branch + "/serviceable").c_str());
+ fgUntie((branch + "/spin").c_str());
}
void
AttitudeIndicator::update (double dt)
{
+ // If it's caged, it doesn't indicate
+ if (_caged_node->getBoolValue()) {
+ _roll_int_node->setDoubleValue(0.0);
+ _pitch_int_node->setDoubleValue(0.0);
+ return;
+ }
+
// Get the spin from the gyro
_gyro.set_power_norm(_suction_node->getDoubleValue()/5.0);
_gyro.update(dt);
// Calculate the tumble for the
// next pass.
if (_tumble_flag_node->getBoolValue()) {
- if (_tumble < 1.0) {
- if (fabs(roll) > 45.0) {
- double target = (fabs(roll) - 45.0) / 45.0;
- if (_tumble < target)
- _tumble = target;
- }
- if (fabs(pitch) > 45.0) {
- double target = (fabs(pitch) - 45.0) / 45.0;
- if (_tumble < target)
- _tumble = target;
- }
- if (_tumble > 1.0) {
- _tumble = 1.0;
- }
+ double tumble = _tumble_node->getDoubleValue();
+ if (fabs(roll) > 45.0) {
+ double target = (fabs(roll) - 45.0) / 45.0;
+ target *= target; // exponential past +-45 degrees
+ if (roll < 0)
+ target = -target;
+
+ if (fabs(target) > fabs(tumble))
+ tumble = target;
+
+ if (tumble > 1.0)
+ tumble = 1.0;
+ else if (tumble < -1.0)
+ tumble = -1.0;
}
- // Reerect in 5 minutes
- _tumble -= dt/300.0;
- if (_tumble < 0.0)
- _tumble = 0.0;
-
- responsiveness *= ((1.0 - _tumble) * (1.0 - _tumble) *
- (1.0 - _tumble) * (1.0 - _tumble));
-
+ // Reerect in 5 minutes
+ double step = dt/300.0;
+ if (tumble < -step)
+ tumble += step;
+ else if (tumble > step)
+ tumble -= step;
+
+ roll += tumble * 45;
+ _tumble_node->setDoubleValue(tumble);
}
- roll = fgGetLowPass(_roll_out_node->getDoubleValue(), roll,
+ roll = fgGetLowPass(_roll_int_node->getDoubleValue(), roll,
responsiveness);
- pitch = fgGetLowPass(_pitch_out_node->getDoubleValue(), pitch,
+ pitch = fgGetLowPass(_pitch_int_node->getDoubleValue(), pitch,
responsiveness);
// Assign the new values
- _roll_out_node->setDoubleValue(roll);
- _pitch_out_node->setDoubleValue(pitch);
+ _roll_int_node->setDoubleValue(roll);
+ _pitch_int_node->setDoubleValue(pitch);
+
+ // add in a gyro underspin "error" if gyro is spinning too slowly
+ const double spin_thresh = 0.8;
+ const double max_roll_error = 40.0;
+ const double max_pitch_error = 12.0;
+ double roll_error;
+ double pitch_error;
+ if ( spin <= spin_thresh ) {
+ double roll_error_factor = (spin_thresh - spin) / spin_thresh;
+ double pitch_error_factor = (spin_thresh - spin) / spin_thresh;
+ roll_error = roll_error_factor * roll_error_factor * max_roll_error;
+ pitch_error = pitch_error_factor * pitch_error_factor * max_pitch_error;
+ } else {
+ roll_error = 0.0;
+ pitch_error = 0.0;
+ }
+
+ _roll_out_node->setDoubleValue(roll + roll_error);
+ _pitch_out_node->setDoubleValue(pitch + pitch_error);
}
// end of attitude_indicator.cxx
projects / flightgear.git / blobdiff