X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=src%2FInstrumentation%2Fheading_indicator_dg.cxx;h=8966c0f3de8292c084bd673f007c63d3f53f2a97;hb=ccb890447ae2f950b8032649ca8b8190bdafaf90;hp=82a35d309854e2bcdac93f1399636c0c133339f3;hpb=12d10066a68922830c9870b1d49d6905789af192;p=flightgear.git diff --git a/src/Instrumentation/heading_indicator_dg.cxx b/src/Instrumentation/heading_indicator_dg.cxx index 82a35d309..8966c0f3d 100644 --- a/src/Instrumentation/heading_indicator_dg.cxx +++ b/src/Instrumentation/heading_indicator_dg.cxx @@ -1,184 +1,207 @@ -// heading_indicator_dg.cxx - a Directional Gyro (DG) compass. -// Based on the vacuum driven Heading Indicator Written by David Megginson, -// started 2002. -// -// Written by Vivian Meazza, started 2005. -// -// This file is in the Public Domain and comes with no warranty. - -#include -#include -#include -#include -#include - -#include
-#include
- -#include "heading_indicator_dg.hxx" - - -HeadingIndicatorDG::HeadingIndicatorDG ( SGPropertyNode *node ) : - name("heading-indicator-dg"), - num(0) -{ - 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 = child->getIntValue(); - } else { - SG_LOG( SG_INSTR, SG_WARN, "Error in DG heading-indicator config logic" ); - if ( name.length() ) { - SG_LOG( SG_INSTR, SG_WARN, "Section = " << name ); - } - } - } -} - -HeadingIndicatorDG::HeadingIndicatorDG () -{ -} - -HeadingIndicatorDG::~HeadingIndicatorDG () -{ -} - -void -HeadingIndicatorDG::init () -{ - string branch; - branch = "/instrumentation/" + name; - +// heading_indicator_dg.cxx - a Directional Gyro (DG) compass. +// Based on the vacuum driven Heading Indicator Written by David Megginson, +// started 2002. +// +// Written by Vivian Meazza, started 2005. +// +// This file is in the Public Domain and comes with no warranty. + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include +#include +#include +#include +#include +#include + +#include
+#include
+ +#include "heading_indicator_dg.hxx" + +/** Macro calculating x^6 (faster than super-slow math/pow). */ +#define POW6(x) (x*x*x*x*x*x) + +HeadingIndicatorDG::HeadingIndicatorDG ( SGPropertyNode *node ) : + name("heading-indicator-dg"), + num(0) +{ + int i; + for ( i = 0; i < node->nChildren(); ++i ) { + SGPropertyNode *child = node->getChild(i); + std::string cname = child->getName(); + std::string cval = child->getStringValue(); + if ( cname == "name" ) { + name = cval; + } else if ( cname == "number" ) { + num = child->getIntValue(); + } else { + SG_LOG( SG_INSTR, SG_WARN, "Error in DG heading-indicator config logic" ); + if ( name.length() ) { + SG_LOG( SG_INSTR, SG_WARN, "Section = " << name ); + } + } + } +} + +HeadingIndicatorDG::~HeadingIndicatorDG () +{ +} + +void +HeadingIndicatorDG::init () +{ + std::string branch; + branch = "/instrumentation/" + name; + _heading_in_node = fgGetNode("/orientation/heading-deg", true); _yaw_rate_node = fgGetNode("/orientation/yaw-rate-degps", true); - _g_node = fgGetNode("/accelerations/pilot-g", true); - - - SGPropertyNode *node = fgGetNode(branch.c_str(), num, true ); - _offset_node = node->getChild("offset-deg", 0, true); - _serviceable_node = node->getChild("serviceable", 0, true); - _heading_bug_error_node = node->getChild("heading-bug-error-deg", 0, true); - _error_node = node->getChild("error-deg", 0, true); - _nav1_error_node = node->getChild("nav1-course-error-deg", 0, true); - _heading_out_node = node->getChild("indicated-heading-deg", 0, true); - _align_node = node->getChild("align-deg", 0, true); - - _electrical_node = fgGetNode("/systems/electrical/outputs/DG", true); - - _align_node->setDoubleValue(0); - _error_node->setDoubleValue(0); - - _last_heading_deg = (_heading_in_node->getDoubleValue() + - _offset_node->getDoubleValue() + _align_node->getDoubleValue()); -} - -void -HeadingIndicatorDG::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 -HeadingIndicatorDG::unbind () -{ - std::ostringstream temp; - string branch; - temp << num; - branch = "/instrumentation/" + name + "[" + temp.str() + "]"; - - fgUntie((branch + "/serviceable").c_str()); - fgUntie((branch + "/spin").c_str()); -} - -void -HeadingIndicatorDG::update (double dt) -{ - // Get the spin from the gyro - _gyro.set_power_norm(_electrical_node->getDoubleValue()); - - _gyro.update(dt); - double spin = _gyro.get_spin_norm(); - - // Next, calculate time-based precession - double offset = _offset_node->getDoubleValue(); - offset -= dt * (0.25 / 60.0); // 360deg/day - SG_NORMALIZE_RANGE(offset, -360.0, 360.0); - - // No magvar - set the alignment manually - double align = _align_node->getDoubleValue(); - - // Movement-induced error - double yaw_rate = _yaw_rate_node->getDoubleValue(); - double error = _error_node->getDoubleValue(); - double g = _g_node->getDoubleValue(); - int sign = 0; + _g_node = fgGetNode("/accelerations/pilot-g", true); + + SGPropertyNode *node = fgGetNode(branch.c_str(), num, true ); + _offset_node = node->getChild("offset-deg", 0, true); + _serviceable_node = node->getChild("serviceable", 0, true); + _heading_bug_error_node = node->getChild("heading-bug-error-deg", 0, true); + _error_node = node->getChild("error-deg", 0, true); + _nav1_error_node = node->getChild("nav1-course-error-deg", 0, true); + _heading_out_node = node->getChild("indicated-heading-deg", 0, true); + _align_node = node->getChild("align-deg", 0, true); + + _electrical_node = fgGetNode("/systems/electrical/outputs/DG", true); + + reinit(); +} + +void +HeadingIndicatorDG::bind () +{ + std::ostringstream temp; + std::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 +HeadingIndicatorDG::unbind () +{ + std::ostringstream temp; + std::string branch; + temp << num; + branch = "/instrumentation/" + name + "[" + temp.str() + "]"; + + fgUntie((branch + "/serviceable").c_str()); + fgUntie((branch + "/spin").c_str()); +} + +void +HeadingIndicatorDG::reinit (void) +{ + // reset errors/drift values + _align_node->setDoubleValue(0.0); + _error_node->setDoubleValue(0.0); + _offset_node->setDoubleValue(0.0); + _last_heading_deg = _heading_in_node->getDoubleValue(); + _last_indicated_heading_dg = _last_heading_deg; + + _gyro.reinit(); +} + +void +HeadingIndicatorDG::update (double dt) +{ + // Get the spin from the gyro + _gyro.set_power_norm(_electrical_node->getDoubleValue()); + + _gyro.update(dt); + + // read inputs + double spin = _gyro.get_spin_norm(); + double heading = _heading_in_node->getDoubleValue(); + double offset = _offset_node->getDoubleValue(); + + // calculate scaling factor + double factor = POW6(spin); + + // calculate time-based precession (scaled by spin factor, since + // there is no precession when the gyro is stuck). + offset -= dt * (0.25 / 60.0) * factor; // 360deg/day + + // indication should get more and more stuck at low gyro spins + if (spin < 0.9) + { + // when gyro spin is low, then any heading change results in + // increasing the offset + double diff = SGMiscd::normalizePeriodic(-180.0, 180.0, _last_heading_deg - heading); + // scaled by 1-factor, so indication is fully stuck at spin==0 (offset compensates + // any heading change) + offset += diff * (1.0-factor); + } + _last_heading_deg = heading; + + // normalize offset + offset = SGMiscd::normalizePeriodic(-180.0,180.0,offset); + _offset_node->setDoubleValue(offset); + + // No magvar - set the alignment manually + double align = _align_node->getDoubleValue(); + + // Movement-induced error + double yaw_rate = _yaw_rate_node->getDoubleValue(); + double error = _error_node->getDoubleValue(); + double g = _g_node->getDoubleValue(); if ( fabs ( yaw_rate ) > 5 ) { - sign = (yaw_rate < 0 ? -1 : 1); - error += 0.033 * -yaw_rate * dt ; + error += 0.033 * -yaw_rate * dt * factor; } if ( g > 1.5 || g < -0.5){ - sign = (g < 0 ? -1 : 1); - error += 0.033 * g * dt; + error += 0.033 * g * dt * factor; } - _error_node->setDoubleValue(error); - // Next, calculate the indicated heading, - // introducing errors. - double factor = 100 * (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; - - heading += offset + align + error; - SG_NORMALIZE_RANGE(heading, 0.0, 360.0); - - _heading_out_node->setDoubleValue(heading); - - // calculate the difference between the indicacted heading - // and the selected heading for use with an autopilot - static SGPropertyNode *bnode - = fgGetNode( "/autopilot/settings/heading-bug-deg", false ); - if ( bnode ) { - double diff = bnode->getDoubleValue() - heading; - if ( diff < -180.0 ) { diff += 360.0; } - if ( diff > 180.0 ) { diff -= 360.0; } - _heading_bug_error_node->setDoubleValue( diff ); - } - // calculate the difference between the indicated heading - // and the selected nav1 radial for use with an autopilot - SGPropertyNode *nnode - = fgGetNode( "/instrumentation/nav/radials/selected-deg", false ); - if ( nnode ) { - double diff = nnode->getDoubleValue() - heading; - if ( diff < -180.0 ) { diff += 360.0; } - if ( diff > 180.0 ) { diff -= 360.0; } - _nav1_error_node->setDoubleValue( diff ); - } -} - -// end of heading_indicator_dg.cxx + // Now, we have to get the current + // heading and the last heading into + // the same range. + while ((heading - _last_indicated_heading_dg) > 180) + _last_indicated_heading_dg += 360; + while ((heading - _last_indicated_heading_dg) < -180) + _last_indicated_heading_dg -= 360; + heading = fgGetLowPass(_last_indicated_heading_dg, heading, dt * 100); + _last_indicated_heading_dg = heading; + + heading += offset + align + error; + heading = SGMiscd::normalizePeriodic(0.0,360.0,heading); + + _heading_out_node->setDoubleValue(heading); + + // calculate the difference between the indicated heading + // and the selected heading for use with an autopilot + static SGPropertyNode *bnode + = fgGetNode( "/autopilot/settings/heading-bug-deg", false ); + if ( bnode ) { + double diff = bnode->getDoubleValue() - heading; + if ( diff < -180.0 ) { diff += 360.0; } + if ( diff > 180.0 ) { diff -= 360.0; } + _heading_bug_error_node->setDoubleValue( diff ); + } + // calculate the difference between the indicated heading + // and the selected nav1 radial for use with an autopilot + SGPropertyNode *nnode + = fgGetNode( "/instrumentation/nav/radials/selected-deg", false ); + if ( nnode ) { + double diff = nnode->getDoubleValue() - heading; + if ( diff < -180.0 ) { diff += 360.0; } + if ( diff > 180.0 ) { diff -= 360.0; } + _nav1_error_node->setDoubleValue( diff ); + } +} + +// end of heading_indicator_dg.cxx