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- Code cleanups.

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- Fix a warning about class member initialization order.
- Clear up a problem with the default autopilot behavior on the back side
  of an ILS in preparation for adding a real "back course" approach mode.
This commit is contained in:
curt 2006-07-18 21:35:11 +00:00
parent cf15a49438
commit c1d06064c8
1 changed files with 41 additions and 30 deletions
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71
src/Instrumentation/navradio.cxx
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@ -52,8 +52,6 @@ FGNavRadio::FGNavRadio(SGPropertyNode *node) :
power_btn_node(NULL),
freq_node(NULL),
alt_freq_node(NULL),
fmt_freq_node(NULL),
fmt_alt_freq_node(NULL),
sel_radial_node(NULL),
vol_btn_node(NULL),
ident_btn_node(NULL),
@ -62,6 +60,8 @@ FGNavRadio::FGNavRadio(SGPropertyNode *node) :
cdi_serviceable_node(NULL),
gs_serviceable_node(NULL),
tofrom_serviceable_node(NULL),
fmt_freq_node(NULL),
fmt_alt_freq_node(NULL),
heading_node(NULL),
radial_node(NULL),
recip_radial_node(NULL),
@ -423,6 +423,8 @@ FGNavRadio::update(double dt)
//////////////////////////////////////////////////////////
// adjust reception range for altitude
// FIXME: make sure we are using the navdata range now that
// it is valid in the data file
//////////////////////////////////////////////////////////
if ( is_loc ) {
double offset = radial - target_radial;
@ -430,10 +432,11 @@ FGNavRadio::update(double dt)
while ( offset > 180.0 ) { offset -= 360.0; }
// cout << "ils offset = " << offset << endl;
effective_range
= adjustILSRange( nav_elev, pos.getElevationM(), offset,
loc_dist * SG_METER_TO_NM );
= adjustILSRange( nav_elev, pos.getElevationM(), offset,
loc_dist * SG_METER_TO_NM );
} else {
effective_range = adjustNavRange( nav_elev, pos.getElevationM(), range );
effective_range
= adjustNavRange( nav_elev, pos.getElevationM(), range );
}
// cout << "nav range = " << effective_range
// << " (" << range << ")" << endl;
@ -494,13 +497,14 @@ FGNavRadio::update(double dt)
// of ( -10 , 10 )
//////////////////////////////////////////////////////////
double r = 0.0;
bool loc_bc = false; // an in-code flag indicating that we are
// on a localizer backcourse.
if ( cdi_serviceable ) {
if ( nav_slaved_to_gps_node->getBoolValue() ) {
r = gps_cdi_deflection_node->getDoubleValue();
// We want +- 5 dots deflection for the gps, so clamp
// to -12.5/12.5
if ( r < -12.5 ) { r = -12.5; }
if ( r > 12.5 ) { r = 12.5; }
SG_CLAMP_RANGE( r, -12.5, 12.5 );
} else if ( inrange ) {
r = radial - target_radial;
// cout << "Target radial = " << target_radial
@ -510,14 +514,19 @@ FGNavRadio::update(double dt)
while ( r < -180.0 ) { r += 360.0;}
if ( fabs(r) > 90.0 ) {
r = ( r<0.0 ? -r-180.0 : -r+180.0 );
} else {
if ( is_loc ) {
loc_bc = true;
}
}
// According to Robin Peel, the ILS is 4x more
// sensitive than a vor
r = -r; // reverse, since radial is outbound
if ( is_loc ) { r *= 4.0; }
if ( r < -10.0 ) { r = -10.0; }
if ( r > 10.0 ) { r = 10.0; }
if ( is_loc ) {
// According to Robin Peel, the ILS is 4x more
// sensitive than a vor
r *= 4.0;
}
SG_CLAMP_RANGE( r, -10.0, 10.0 );
}
}
cdi_deflection_node->setDoubleValue( r );
@ -643,30 +652,32 @@ FGNavRadio::update(double dt)
// a nav/ils radial.
//////////////////////////////////////////////////////////
// FIXME: this smells odd, there must be a better (or more
// linear) solution
// Now that we have cross track heading adjustment built in,
// we shouldn't need to overdrive the heading angle within 8km
// of the station.
//
// determine the heading adjustment needed.
// over 8km scale by 3.0
// (3 is chosen because max deflection is 10
// and 30 is clamped angle to radial)
// under 8km scale by 10.0
// because the overstated error helps drive it to the radial in a
// moderate cross wind.
double adjustment = 0.0;
if ( loc_dist > 8000 ) {
adjustment = cdi_deflection_node->getDoubleValue() * 3.0;
} else {
adjustment = cdi_deflection_node->getDoubleValue() * 10.0;
}
// The cdi deflection should be +/-10 for a full range of deflection
// so multiplying this by 3 gives us +/- 30 degrees heading
// compensation.
double adjustment = cdi_deflection_node->getDoubleValue() * 3.0;
SG_CLAMP_RANGE( adjustment, -30.0, 30.0 );
// determine the target heading to fly to intercept the
// tgt_radial = target radial (true) + cdi offset adjustmest -
// xtrack heading error adjustment
double nta_hdg = trtrue + adjustment - hdg_error;
// cout << "trtrue = " << trtrue << " adj = " << adjustment
// << " hdg_error = " << hdg_error << endl;
double nta_hdg = 0.0;
if ( is_loc && loc_bc ) {
// tuned to a localizer and positioned in backcourse range
// trtrue += 180.0; // reverse the target localizer heading
// while ( trtrue > 360.0 ) { trtrue -= 360.0; }
nta_hdg = trtrue + adjustment - hdg_error;
cout << "trtrue = " << trtrue << " adj = " << adjustment
<< " hdg_error = " << hdg_error << endl;
} else {
// all other situations (nav or loc front course)
nta_hdg = trtrue + adjustment - hdg_error;
}
while ( nta_hdg < 0.0 ) { nta_hdg += 360.0; }
while ( nta_hdg >= 360.0 ) { nta_hdg -= 360.0; }
target_auto_hdg_node->setDoubleValue( nta_hdg );