Move aircraft-performance code into a public API
Upcoming flight-planning changes want to use the perf computation code in route-path, so move it to a public class, and implement some of the missing functionality, especially correct GS computation for altitude.
This commit is contained in:
James Turner
parent
e425f74a7d
commit
e3d032942e
10 changed files with 659 additions and 159 deletions
390
src/Aircraft/AircraftPerformance.cxx
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390
src/Aircraft/AircraftPerformance.cxx
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// AircraftPerformance.cxx - compute data about planned acft performance
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//
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// Copyright (C) 2018 James Turner <james@flightgear.org>
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// This program is free software; you can redistribute it and/or
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// modify it under the terms of the GNU General Public License as
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// published by the Free Software Foundation; either version 2 of the
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// License, or (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful, but
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// WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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#include "AircraftPerformance.hxx"
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#include <cassert>
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#include <simgear/constants.h>
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#include <Main/fg_props.hxx>
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using namespace flightgear;
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double distanceForTimeAndSpeeds(double tSec, double v1, double v2)
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{
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return tSec * 0.5 * (v1 + v2);
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}
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AircraftPerformance::AircraftPerformance()
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{
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// read aircraft supplied performance data
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if (fgGetNode("/aircraft/performance/bracket")) {
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readPerformanceData();
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} else {
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// falls back to heuristic determination of the category,
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// and a plausible default
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icaoCategoryData();
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}
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}
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double AircraftPerformance::groundSpeedForAltitudeKnots(int altitudeFt) const
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{
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auto bracket = bracketForAltitude(altitudeFt);
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return bracket->gsForAltitude(altitudeFt);
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}
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int AircraftPerformance::computePreviousAltitude(double distanceM, int targetAltFt) const
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{
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auto bracket = bracketForAltitude(targetAltFt);
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auto d = bracket->descendDistanceM(bracket->atOrBelowAltitudeFt, targetAltFt);
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if (d < distanceM) {
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// recurse to previous bracket
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return computePreviousAltitude(distanceM - d, bracket->atOrBelowAltitudeFt+1);
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}
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// work out how far we travel laterally per foot change in altitude
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// this value is in metres, we have to map FPM and GS in Knots to make
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// everything work out
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const double gsMPS = bracket->gsForAltitude(targetAltFt) * SG_KT_TO_MPS;
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const double t = distanceM / gsMPS;
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return targetAltFt + bracket->descentRateFPM * (t / 60.0);
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}
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int AircraftPerformance::computeNextAltitude(double distanceM, int initialAltFt) const
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{
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auto bracket = bracketForAltitude(initialAltFt);
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auto d = bracket->climbDistanceM(initialAltFt, bracket->atOrBelowAltitudeFt);
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if (d < distanceM) {
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// recurse to next bracket
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return computeNextAltitude(distanceM - d, bracket->atOrBelowAltitudeFt+1);
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}
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// work out how far we travel laterally per foot change in altitude
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// this value is in metres, we have to map FPM and GS in Knots to make
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// everything work out
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const double gsMPS = bracket->gsForAltitude(initialAltFt) * SG_KT_TO_MPS;
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const double t = distanceM / gsMPS;
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return initialAltFt + bracket->climbRateFPM * (t / 60.0);
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}
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static string_list readTags()
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{
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string_list r;
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const auto tagsNode = fgGetNode("/sim/tags");
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if (!tagsNode)
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return r;
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for (auto t : tagsNode->getChildren("tag")) {
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r.push_back(t->getStringValue());
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}
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return r;
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}
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static bool stringListContains(const string_list& t, const std::string& s)
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{
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auto it = std::find(t.begin(), t.end(), s);
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return it != t.end();
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}
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std::string AircraftPerformance::heuristicCatergoryFromTags() const
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{
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const auto tags(readTags());
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if (stringListContains(tags, "turboprop"))
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return {ICAO_AIRCRAFT_CATEGORY_C};
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// any way we could distuinguish fast and slow GA aircraft?
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if (stringListContains(tags, "ga")) {
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return {ICAO_AIRCRAFT_CATEGORY_A};
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}
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if (stringListContains(tags, "jet")) {
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return {ICAO_AIRCRAFT_CATEGORY_E};
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}
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return {ICAO_AIRCRAFT_CATEGORY_C};
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}
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void AircraftPerformance::icaoCategoryData()
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{
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std::string propCat = fgGetString("/aircraft/performance/icao-category");
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if (propCat.empty()) {
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propCat = heuristicCatergoryFromTags();
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}
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const char aircraftCategory = propCat.front();
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// pathTurnRate = 3.0; // 3 deg/sec = 180deg/min = standard rate turn
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switch (aircraftCategory) {
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case ICAO_AIRCRAFT_CATEGORY_A:
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_perfData.push_back(Bracket(4000, 600, 1200, 75));
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_perfData.push_back(Bracket(10000, 600, 1200, 140));
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break;
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case ICAO_AIRCRAFT_CATEGORY_B:
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_perfData.push_back(Bracket(4000, 100, 1200, 100));
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_perfData.push_back(Bracket(10000, 800, 1200, 160));
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_perfData.push_back(Bracket(18000, 600, 1800, 200));
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break;
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case ICAO_AIRCRAFT_CATEGORY_C:
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_perfData.push_back(Bracket(4000, 1800, 1800, 150));
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_perfData.push_back(Bracket(10000, 1800, 1800, 200));
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_perfData.push_back(Bracket(18000, 1200, 1800, 270));
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_perfData.push_back(Bracket(60000, 800, 1200, 0.80, true /* is Mach */));
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break;
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case ICAO_AIRCRAFT_CATEGORY_D:
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case ICAO_AIRCRAFT_CATEGORY_E:
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default:
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_perfData.push_back(Bracket(4000, 1800, 1800, 180));
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_perfData.push_back(Bracket(10000, 1800, 1800, 230));
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_perfData.push_back(Bracket(18000, 1200, 1800, 270));
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_perfData.push_back(Bracket(60000, 800, 1200, 0.87, true /* is Mach */));
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break;
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}
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}
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void AircraftPerformance::readPerformanceData()
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{
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for (auto nd : fgGetNode("/aircraft/performance/")->getChildren("bracket")) {
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const int atOrBelowAlt = nd->getIntValue("at-or-below-ft");
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const int climbFPM = nd->getIntValue("climb-rate-fpm");
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const int descentFPM = nd->getIntValue("descent-rate-fpm");
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bool isMach = nd->hasChild("speed-mach");
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double speed;
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if (isMach) {
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speed = nd->getDoubleValue("speed-mach");
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} else {
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speed = nd->getIntValue("speed-ias-knots");
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}
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Bracket b(atOrBelowAlt, climbFPM, descentFPM, speed, isMach);
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_perfData.push_back(b);
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}
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}
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auto AircraftPerformance::bracketForAltitude(int altitude) const
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-> PerformanceVec::const_iterator
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{
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assert(!_perfData.empty());
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if (_perfData.front().atOrBelowAltitudeFt >= altitude)
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return _perfData.begin();
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for (auto it = _perfData.begin(); it != _perfData.end(); ++it) {
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if (it->atOrBelowAltitudeFt > altitude) {
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return it;
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}
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}
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return _perfData.end() - 1;
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}
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auto AircraftPerformance::rangeForAltitude(int lowAltitude, int highAltitude) const
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-> BracketRange
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{
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return {bracketForAltitude(lowAltitude), bracketForAltitude(highAltitude)};
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}
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void AircraftPerformance::traverseAltitudeRange(int initialElevationFt, int targetElevationFt,
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TraversalFunc tf) const
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{
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auto r = rangeForAltitude(initialElevationFt, targetElevationFt);
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if (r.first == r.second) {
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tf(*r.first, initialElevationFt, targetElevationFt);
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return;
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}
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if (initialElevationFt < targetElevationFt) {
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tf(*r.first, initialElevationFt, r.first->atOrBelowAltitudeFt);
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int previousBracketCapAltitude = r.first->atOrBelowAltitudeFt;
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for (auto bracket = r.first + 1; bracket != r.second; ++bracket) {
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tf(*bracket, previousBracketCapAltitude, bracket->atOrBelowAltitudeFt);
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previousBracketCapAltitude = bracket->atOrBelowAltitudeFt;
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}
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tf(*r.second, previousBracketCapAltitude, targetElevationFt);
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} else {
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int nextBracketCapAlt = (r.first - 1)->atOrBelowAltitudeFt;
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tf(*r.first, initialElevationFt, nextBracketCapAlt);
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for (auto bracket = r.first - 1; bracket != r.second; --bracket) {
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nextBracketCapAlt = (r.first - 1)->atOrBelowAltitudeFt;
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tf(*bracket, bracket->atOrBelowAltitudeFt, nextBracketCapAlt);
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}
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tf(*r.second, nextBracketCapAlt, targetElevationFt);
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}
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}
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double AircraftPerformance::distanceNmBetween(int initialElevationFt, int targetElevationFt) const
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{
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double result = 0.0;
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TraversalFunc tf = [&result](const Bracket& bk, int alt1, int alt2) {
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result += (alt1 > alt2) ? bk.descendDistanceM(alt1, alt2) : bk.climbDistanceM(alt1, alt2);
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};
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traverseAltitudeRange(initialElevationFt, targetElevationFt, tf);
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return result * SG_METER_TO_NM;
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}
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double AircraftPerformance::timeBetween(int initialElevationFt, int targetElevationFt) const
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{
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double result = 0.0;
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TraversalFunc tf = [&result](const Bracket& bk, int alt1, int alt2) {
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SG_LOG(SG_GENERAL, SG_INFO, "Range:" << alt1 << " " << alt2);
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result += (alt1 > alt2) ? bk.descendTime(alt1, alt2) : bk.climbTime(alt1, alt2);
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};
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traverseAltitudeRange(initialElevationFt, targetElevationFt, tf);
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return result;
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}
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double AircraftPerformance::timeToCruise(double cruiseDistanceNm, int cruiseAltitudeFt) const
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{
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auto b = bracketForAltitude(cruiseAltitudeFt);
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return (cruiseDistanceNm / b->gsForAltitude(cruiseAltitudeFt)) * 3600.0;
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}
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double oatCForAltitudeFt(int altitudeFt)
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{
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if (altitudeFt > 36089)
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return -56.5;
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// lapse rate in C per ft
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const double T_r = .0019812;
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return 15.0 - (altitudeFt * T_r);
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}
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double oatKForAltitudeFt(int altitudeFt)
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{
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return oatCForAltitudeFt(altitudeFt) + 273.15;
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}
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double pressureAtAltitude(int altitude)
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{
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#if 0
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p= P_0*(1-6.8755856*10^-6 h)^5.2558797 h<36,089.24ft
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p_Tr= 0.2233609*P_0
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p=p_Tr*exp(-4.806346*10^-5(h-36089.24)) h>36,089.24ft
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magic numbers
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6.8755856*10^-6 = T'/T_0, where T' is the standard temperature lapse rate and T_0 is the standard sea-level temperature.
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5.2558797 = Mg/RT', where M is the (average) molecular weight of air, g is the acceleration of gravity and R is the gas constant.
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4.806346*10^-5 = Mg/RT_tr, where T_tr is the temperature at the tropopause.
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#endif
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const double k = 6.8755856e-6;
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const double MgRT = 5.2558797;
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const double MgRT_tr = 4.806346e-5;
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const double P_0 = 29.92126; // (standard) sea-level pressure
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if (altitude > 36089) {
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const double P_Tr = 0.2233609 * P_0;
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const double altAboveTr = altitude - 36089;
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return P_Tr * exp(MgRT_tr * altAboveTr);
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} else {
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return P_0 * pow(1.0 - (k * altitude), MgRT);
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}
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}
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double computeMachFromIAS(int iasKnots, int altitudeFt)
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{
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#if 0
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// from the aviation formulary
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DP=P_0*((1 + 0.2*(IAS/CS_0)^2)^3.5 -1)
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M=(5*( (DP/P + 1)^(2/7) -1) )^0.5 (*)
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#endif
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const double Cs_0 = 661.4786; // speed of sound at sea level, knots
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const double P_0 = 29.92126; // (standard) sea-level pressure
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const double iasCsRatio = iasKnots / Cs_0;
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const double P = pressureAtAltitude(altitudeFt);
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// differential pressure
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const double DP = P_0 * (pow(1.0 + 0.2 * pow(iasCsRatio, 2.0), 3.5) - 1.0);
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const double pressureRatio = DP / P + 1.0;
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const double M = pow(5.0 * (pow(pressureRatio, 2.0 / 7.0) - 1.0), 0.5);
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if (M > 1.0) {
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SG_LOG(SG_GENERAL, SG_INFO, "computeMachFromIAS: computed Mach is supersonic, fix for shock wave");
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}
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return M;
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}
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int AircraftPerformance::Bracket::gsForAltitude(int altitude) const
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{
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double M = 0.0;
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if (speedIsMach) {
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M = speedIASOrMach; // simple
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} else {
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M = computeMachFromIAS(speedIASOrMach, altitude);
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}
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// CS = sound speed= 38.967854*sqrt(T+273.15) where T is the OAT in celsius.
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const double CS = 38.967854 * sqrt(oatKForAltitudeFt(altitude));
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const double TAS = M * CS;
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return TAS;
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}
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double AircraftPerformance::Bracket::climbTime(int alt1, int alt2) const
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{
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return (alt2 - alt1) / static_cast<double>(climbRateFPM) * 60.0;
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}
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double AircraftPerformance::Bracket::climbDistanceM(int alt1, int alt2) const
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{
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const double t = climbTime(alt1, alt2);
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return distanceForTimeAndSpeeds(t,
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SG_KT_TO_MPS * gsForAltitude(alt1),
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SG_KT_TO_MPS * gsForAltitude(alt2));
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}
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double AircraftPerformance::Bracket::descendTime(int alt1, int alt2) const
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{
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return (alt1 - alt2) / static_cast<double>(descentRateFPM) * 60.0;
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}
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double AircraftPerformance::Bracket::descendDistanceM(int alt1, int alt2) const
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{
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const double t = descendTime(alt1, alt2);
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return distanceForTimeAndSpeeds(t,
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SG_KT_TO_MPS * gsForAltitude(alt1),
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SG_KT_TO_MPS * gsForAltitude(alt2));
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}
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double AircraftPerformance::turnRadiusMForAltitude(int altitudeFt) const
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{
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#if 0
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From the aviation formulary again
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In a steady turn, in no wind, with bank angle, b at an airspeed v
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tan(b)= v^2/(R g)
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With R in feet, v in knots, b in degrees and w in degrees/sec (inconsistent units!), numerical constants are introduced:
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R =v^2/(11.23*tan(0.01745*b))
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(Example) At 100 knots, with a 45 degree bank, the radius of turn is 100^2/(11.23*tan(0.01745*45))= 891 feet.
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The bank angle b_s for a standard rate turn is given by:
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b_s = 57.3*atan(v/362.1)
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(Example) for 100 knots, b_s = 57.3*atan(100/362.1) = 15.4 degrees
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Working in meter-per-second and radians removes a bunch of constants again.
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#endif
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const double gsKts = groundSpeedForAltitudeKnots(altitudeFt);
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const double gs = gsKts * SG_KT_TO_MPS;
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const double bankAngleRad = atan(gsKts/362.1);
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const double r = (gs * gs)/(SG_g0_m_p_s2 * tan(bankAngleRad));
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return r;
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}
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112
src/Aircraft/AircraftPerformance.hxx
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112
src/Aircraft/AircraftPerformance.hxx
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// AircraftPerformance.hxx - compute data about planned acft performance
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//
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// Copyright (C) 2018 James Turner <james@flightgear.org>
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// This program is free software; you can redistribute it and/or
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// modify it under the terms of the GNU General Public License as
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// published by the Free Software Foundation; either version 2 of the
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// License, or (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful, but
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// WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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#ifndef AIRCRAFTPERFORMANCE_HXX
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#define AIRCRAFTPERFORMANCE_HXX
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#include <vector>
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#include <functional>
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namespace flightgear
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{
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const char ICAO_AIRCRAFT_CATEGORY_A = 'A';
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const char ICAO_AIRCRAFT_CATEGORY_B = 'B';
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const char ICAO_AIRCRAFT_CATEGORY_C = 'C';
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const char ICAO_AIRCRAFT_CATEGORY_D = 'D';
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const char ICAO_AIRCRAFT_CATEGORY_E = 'E';
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/**
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* Calculate flight parameter based on aircraft performance data.
|
||||
* This is based on simple rules: it does not (yet) include data
|
||||
* such as winds aloft, payload or temperature impact on engine
|
||||
* performance. */
|
||||
class AircraftPerformance
|
||||
{
|
||||
public:
|
||||
AircraftPerformance();
|
||||
|
||||
double turnRateDegSec() const;
|
||||
|
||||
double turnRadiusMForAltitude(int altitudeFt) const;
|
||||
|
||||
double groundSpeedForAltitudeKnots(int altitudeFt) const;
|
||||
|
||||
int computePreviousAltitude(double distanceM, int targetAltFt) const;
|
||||
int computeNextAltitude(double distanceM, int initialAltFt) const;
|
||||
|
||||
double distanceNmBetween(int initialElevationFt, int targetElevationFt) const;
|
||||
double timeBetween(int initialElevationFt, int targetElevationFt) const;
|
||||
|
||||
double timeToCruise(double cruiseDistanceNm, int cruiseAltitudeFt) const;
|
||||
|
||||
private:
|
||||
void readPerformanceData();
|
||||
|
||||
void icaoCategoryData();
|
||||
|
||||
/**
|
||||
* @brief heuristicCatergoryFromTags - based on the aircraft tags, figure
|
||||
* out a plausible ICAO category. Returns cat A if nothing better could
|
||||
* be determined.
|
||||
* @return a string containing a single ICAO category character A..E
|
||||
*/
|
||||
std::string heuristicCatergoryFromTags() const;
|
||||
|
||||
class Bracket
|
||||
{
|
||||
public:
|
||||
Bracket(int atOrBelow, int climb, int descent, double speed, bool isMach = false) :
|
||||
atOrBelowAltitudeFt(atOrBelow),
|
||||
climbRateFPM(climb),
|
||||
descentRateFPM(descent),
|
||||
speedIASOrMach(speed),
|
||||
speedIsMach(isMach)
|
||||
{ }
|
||||
|
||||
int gsForAltitude(int altitude) const;
|
||||
|
||||
double climbTime(int alt1, int alt2) const;
|
||||
double climbDistanceM(int alt1, int alt2) const;
|
||||
double descendTime(int alt1, int alt2) const;
|
||||
double descendDistanceM(int alt1, int alt2) const;
|
||||
|
||||
int atOrBelowAltitudeFt;
|
||||
int climbRateFPM;
|
||||
int descentRateFPM;
|
||||
double speedIASOrMach;
|
||||
bool speedIsMach = false;
|
||||
};
|
||||
|
||||
using PerformanceVec = std::vector<Bracket>;
|
||||
|
||||
using BracketRange = std::pair<PerformanceVec::const_iterator, PerformanceVec::const_iterator>;
|
||||
|
||||
PerformanceVec::const_iterator bracketForAltitude(int altitude) const;
|
||||
BracketRange rangeForAltitude(int lowAltitude, int highAltitude) const;
|
||||
|
||||
|
||||
using TraversalFunc = std::function<void(const Bracket& bk, int alt1, int alt2)>;
|
||||
void traverseAltitudeRange(int initialElevationFt, int targetElevationFt, TraversalFunc tf) const;
|
||||
|
||||
|
||||
PerformanceVec _perfData;
|
||||
};
|
||||
|
||||
}
|
||||
|
||||
#endif // AIRCRAFTPERFORMANCE_HXX
|
||||
|
|
@ -6,6 +6,7 @@ set(SOURCES
|
|||
flightrecorder.cxx
|
||||
FlightHistory.cxx
|
||||
initialstate.cxx
|
||||
AircraftPerformance.cxx
|
||||
)
|
||||
|
||||
set(HEADERS
|
||||
|
|
@ -14,6 +15,7 @@ set(HEADERS
|
|||
flightrecorder.hxx
|
||||
FlightHistory.hxx
|
||||
initialstate.hxx
|
||||
AircraftPerformance.hxx
|
||||
)
|
||||
|
||||
|
||||
|
|
|
|||
|
|
@ -49,6 +49,7 @@
|
|||
#include <Navaids/routePath.hxx>
|
||||
#include <Navaids/airways.hxx>
|
||||
#include <Autopilot/route_mgr.hxx>
|
||||
#include <Aircraft/AircraftPerformance.hxx>
|
||||
|
||||
using std::string;
|
||||
using std::vector;
|
||||
|
|
|
|||
|
|
@ -35,12 +35,6 @@ class FlightPlan;
|
|||
|
||||
typedef SGSharedPtr<FlightPlan> FlightPlanRef;
|
||||
|
||||
const char ICAO_AIRCRAFT_CATEGORY_A = 'A';
|
||||
const char ICAO_AIRCRAFT_CATEGORY_B = 'B';
|
||||
const char ICAO_AIRCRAFT_CATEGORY_C = 'C';
|
||||
const char ICAO_AIRCRAFT_CATEGORY_D = 'D';
|
||||
const char ICAO_AIRCRAFT_CATEGORY_E = 'E';
|
||||
|
||||
class FlightPlan : public RouteBase
|
||||
{
|
||||
public:
|
||||
|
|
|
|||
|
|
@ -1,7 +1,21 @@
|
|||
// routePath.hxx - compute data about planned route
|
||||
//
|
||||
// Copyright (C) 2018 James Turner <james@flightgear.org>
|
||||
// This program is free software; you can redistribute it and/or
|
||||
// modify it under the terms of the GNU General Public License as
|
||||
// published by the Free Software Foundation; either version 2 of the
|
||||
// License, or (at your option) any later version.
|
||||
//
|
||||
// This program is distributed in the hope that it will be useful, but
|
||||
// WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
// General Public License for more details.
|
||||
//
|
||||
// You should have received a copy of the GNU General Public License
|
||||
// along with this program; if not, write to the Free Software
|
||||
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
||||
|
||||
#ifdef HAVE_CONFIG_H
|
||||
# include "config.h"
|
||||
#endif
|
||||
#include "config.h"
|
||||
|
||||
#include <algorithm>
|
||||
|
||||
|
|
@ -16,6 +30,7 @@
|
|||
#include <Navaids/waypoint.hxx>
|
||||
#include <Navaids/FlightPlan.hxx>
|
||||
#include <Navaids/positioned.hxx>
|
||||
#include <Aircraft/AircraftPerformance.hxx>
|
||||
|
||||
namespace flightgear {
|
||||
|
||||
|
|
@ -589,26 +604,6 @@ public:
|
|||
|
||||
typedef std::vector<WayptData> WayptDataVec;
|
||||
|
||||
class PerformanceBracket
|
||||
{
|
||||
public:
|
||||
PerformanceBracket(double atOrBelow, double climb, double descent, double speed, bool isMach = false) :
|
||||
atOrBelowAltitudeFt(atOrBelow),
|
||||
climbRateFPM(climb),
|
||||
descentRateFPM(descent),
|
||||
speedIASOrMach(speed),
|
||||
speedIsMach(isMach)
|
||||
{ }
|
||||
|
||||
double atOrBelowAltitudeFt;
|
||||
double climbRateFPM;
|
||||
double descentRateFPM;
|
||||
double speedIASOrMach;
|
||||
bool speedIsMach;
|
||||
};
|
||||
|
||||
typedef std::vector<PerformanceBracket> PerformanceBracketVec;
|
||||
|
||||
bool isDescentWaypoint(const WayptRef& wpt)
|
||||
{
|
||||
return (wpt->flag(WPT_APPROACH) && !wpt->flag(WPT_MISS)) || wpt->flag(WPT_ARRIVAL);
|
||||
|
|
@ -619,28 +614,9 @@ class RoutePath::RoutePathPrivate
|
|||
public:
|
||||
WayptDataVec waypoints;
|
||||
|
||||
char aircraftCategory;
|
||||
PerformanceBracketVec perf;
|
||||
double pathTurnRate;
|
||||
AircraftPerformance perf;
|
||||
bool constrainLegCourses;
|
||||
|
||||
PerformanceBracketVec::const_iterator
|
||||
findPerformanceBracket(double altFt) const
|
||||
{
|
||||
PerformanceBracketVec::const_iterator r;
|
||||
PerformanceBracketVec::const_iterator result = perf.begin();
|
||||
|
||||
for (r = perf.begin(); r != perf.end(); ++r) {
|
||||
if (r->atOrBelowAltitudeFt > altFt) {
|
||||
break;
|
||||
}
|
||||
|
||||
result = r;
|
||||
} // of brackets iteration
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
void computeDynamicPosition(int index)
|
||||
{
|
||||
auto previous(previousValidWaypoint(index));
|
||||
|
|
@ -653,18 +629,7 @@ public:
|
|||
HeadingToAltitude* h = (HeadingToAltitude*) wpt.get();
|
||||
|
||||
double altFt = computeVNAVAltitudeFt(index - 1);
|
||||
double altChange = h->altitudeFt() - altFt;
|
||||
PerformanceBracketVec::const_iterator it = findPerformanceBracket(altFt);
|
||||
double speedMSec = groundSpeedForAltitude(altFt) * SG_KT_TO_MPS;
|
||||
double timeToChangeSec;
|
||||
|
||||
if (isDescentWaypoint(wpt)) {
|
||||
timeToChangeSec = (altChange / it->descentRateFPM) * 60.0;
|
||||
} else {
|
||||
timeToChangeSec = (altChange / it->climbRateFPM) * 60.0;
|
||||
}
|
||||
|
||||
double distanceM = timeToChangeSec * speedMSec;
|
||||
double distanceM = perf.distanceNmBetween(altFt, h->altitudeFt()) * SG_NM_TO_METER;
|
||||
double hdg = h->headingDegMagnetic() + magVarFor(previous->pos);
|
||||
waypoints[index].pos = SGGeodesy::direct(previous->turnExitPos, hdg, distanceM);
|
||||
waypoints[index].posValid = true;
|
||||
|
|
@ -742,12 +707,7 @@ public:
|
|||
|
||||
double fixedAlt = altitudeForIndex(next);
|
||||
double distanceM = distanceBetweenIndices(index, next);
|
||||
double speedMSec = groundSpeedForAltitude(fixedAlt) * SG_KT_TO_MPS;
|
||||
double minutes = (distanceM / speedMSec) / 60.0;
|
||||
|
||||
PerformanceBracketVec::const_iterator it = findPerformanceBracket(fixedAlt);
|
||||
return fixedAlt + (it->descentRateFPM * minutes);
|
||||
|
||||
return perf.computePreviousAltitude(distanceM, fixedAlt);
|
||||
} else {
|
||||
// climb
|
||||
int prev = findPreceedingKnownAltitude(index);
|
||||
|
|
@ -757,13 +717,8 @@ public:
|
|||
|
||||
double fixedAlt = altitudeForIndex(prev);
|
||||
double distanceM = distanceBetweenIndices(prev, index);
|
||||
double speedMSec = groundSpeedForAltitude(fixedAlt) * SG_KT_TO_MPS;
|
||||
double minutes = (distanceM / speedMSec) / 60.0;
|
||||
|
||||
PerformanceBracketVec::const_iterator it = findPerformanceBracket(fixedAlt);
|
||||
return fixedAlt + (it->climbRateFPM * minutes);
|
||||
return perf.computeNextAltitude(distanceM, fixedAlt);
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
int findPreceedingKnownAltitude(int index) const
|
||||
|
|
@ -831,47 +786,6 @@ public:
|
|||
return 0.0;
|
||||
}
|
||||
|
||||
double groundSpeedForAltitude(double altitude) const
|
||||
{
|
||||
PerformanceBracketVec::const_iterator it = findPerformanceBracket(altitude);
|
||||
if (it->speedIsMach) {
|
||||
return 300.0;
|
||||
} else {
|
||||
// FIXME - convert IAS to ground-speed, using standard atmosphere / temperature model
|
||||
return it->speedIASOrMach;
|
||||
}
|
||||
|
||||
#if 0
|
||||
if (0) {
|
||||
double mach;
|
||||
|
||||
if (it->speedIsMach) {
|
||||
mach = it->speedIASOrMach; // easy
|
||||
} else {
|
||||
const double Cs_0 = 661.4786; // speed of sound at sea level, knots
|
||||
const double P_0 = 29.92126;
|
||||
const double P = P_0 * pow(, );
|
||||
// convert IAS (which we will treat as CAS) to Mach based on altitude
|
||||
}
|
||||
|
||||
double oatK;
|
||||
double Cs = sqrt(SG_gamma * SG_R_m2_p_s2_p_K * oatK);
|
||||
|
||||
double tas = mach * Cs;
|
||||
|
||||
/*
|
||||
P_0= 29.92126 "Hg = 1013.25 mB = 2116.2166 lbs/ft^2
|
||||
P= P_0*(1-6.8755856*10^-6*PA)^5.2558797, pressure altitude, PA<36,089.24ft
|
||||
CS= 38.967854*sqrt(T+273.15) where T is the (static/true) OAT in Celsius.
|
||||
|
||||
DP=P_0*((1 + 0.2*(IAS/CS_0)^2)^3.5 -1)
|
||||
M=(5*( (DP/P + 1)^(2/7) -1) )^0.5 (*)
|
||||
TAS= M*CS
|
||||
*/
|
||||
}
|
||||
#endif
|
||||
}
|
||||
|
||||
double distanceBetweenIndices(int from, int to) const
|
||||
{
|
||||
double total = 0.0;
|
||||
|
|
@ -883,40 +797,6 @@ public:
|
|||
return total;
|
||||
}
|
||||
|
||||
void initPerfData()
|
||||
{
|
||||
pathTurnRate = 3.0; // 3 deg/sec = 180deg/min = standard rate turn
|
||||
switch (aircraftCategory) {
|
||||
case ICAO_AIRCRAFT_CATEGORY_A:
|
||||
perf.push_back(PerformanceBracket(4000, 600, 1200, 75));
|
||||
perf.push_back(PerformanceBracket(10000, 600, 1200, 140));
|
||||
break;
|
||||
|
||||
case ICAO_AIRCRAFT_CATEGORY_B:
|
||||
perf.push_back(PerformanceBracket(4000, 100, 1200, 100));
|
||||
perf.push_back(PerformanceBracket(10000, 800, 1200, 160));
|
||||
perf.push_back(PerformanceBracket(18000, 600, 1800, 200));
|
||||
break;
|
||||
|
||||
case ICAO_AIRCRAFT_CATEGORY_C:
|
||||
perf.push_back(PerformanceBracket(4000, 1800, 1800, 150));
|
||||
perf.push_back(PerformanceBracket(10000, 1800, 1800, 200));
|
||||
perf.push_back(PerformanceBracket(18000, 1200, 1800, 270));
|
||||
perf.push_back(PerformanceBracket(60000, 800, 1200, 0.80, true /* is Mach */));
|
||||
break;
|
||||
|
||||
case ICAO_AIRCRAFT_CATEGORY_D:
|
||||
case ICAO_AIRCRAFT_CATEGORY_E:
|
||||
default:
|
||||
|
||||
perf.push_back(PerformanceBracket(4000, 1800, 1800, 180));
|
||||
perf.push_back(PerformanceBracket(10000, 1800, 1800, 230));
|
||||
perf.push_back(PerformanceBracket(18000, 1200, 1800, 270));
|
||||
perf.push_back(PerformanceBracket(60000, 800, 1200, 0.87, true /* is Mach */));
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
WayptDataVec::iterator previousValidWaypoint(unsigned int index)
|
||||
{
|
||||
if (index == 0) {
|
||||
|
|
@ -968,7 +848,6 @@ RoutePath::RoutePath(const flightgear::FlightPlan* fp) :
|
|||
d->waypoints.push_back(WayptData(wpt));
|
||||
}
|
||||
|
||||
d->aircraftCategory = fp->icaoAircraftCategory()[0];
|
||||
d->constrainLegCourses = fp->followLegTrackToFixes();
|
||||
commonInit();
|
||||
}
|
||||
|
|
@ -979,15 +858,13 @@ RoutePath::~RoutePath()
|
|||
|
||||
void RoutePath::commonInit()
|
||||
{
|
||||
d->initPerfData();
|
||||
|
||||
WayptDataVec::iterator it;
|
||||
for (it = d->waypoints.begin(); it != d->waypoints.end(); ++it) {
|
||||
it->initPass0();
|
||||
}
|
||||
|
||||
for (unsigned int i=1; i<d->waypoints.size(); ++i) {
|
||||
WayptData* nextPtr = ((i + 1) < d->waypoints.size()) ? &d->waypoints[i+1] : 0;
|
||||
WayptData* nextPtr = ((i + 1) < d->waypoints.size()) ? &d->waypoints[i+1] : nullptr;
|
||||
d->waypoints[i].initPass1(d->waypoints[i-1], nextPtr);
|
||||
}
|
||||
|
||||
|
|
@ -997,8 +874,7 @@ void RoutePath::commonInit()
|
|||
}
|
||||
|
||||
double alt = 0.0; // FIXME
|
||||
double gs = d->groundSpeedForAltitude(alt);
|
||||
double radiusM = ((360.0 / d->pathTurnRate) * gs * SG_KT_TO_MPS) / SGMiscd::twopi();
|
||||
double radiusM = d->perf.turnRadiusMForAltitude(alt);
|
||||
|
||||
if (i > 0) {
|
||||
auto prevIt = d->previousValidWaypoint(i);
|
||||
|
|
@ -1142,12 +1018,12 @@ SGGeodVec RoutePath::pathForHold(Hold* hold) const
|
|||
double hdg = hold->inboundRadial();
|
||||
double turnDelta = 180.0 / turnSteps;
|
||||
double altFt = 0.0; // FIXME
|
||||
double gsKts = d->groundSpeedForAltitude(altFt);
|
||||
double gsKts = d->perf.groundSpeedForAltitudeKnots(altFt);
|
||||
|
||||
SGGeodVec r;
|
||||
double az2;
|
||||
double stepTime = turnDelta / d->pathTurnRate; // in seconds
|
||||
double stepDist = gsKts * (stepTime / 3600.0) * SG_NM_TO_METER;
|
||||
double stepTime = turnDelta / 3.0; // 3.0 is degrees/sec for standard rate turn
|
||||
double stepDist = gsKts * SG_KT_TO_MPS * stepTime;
|
||||
double legDist = hold->isDistance() ?
|
||||
hold->timeOrDistance()
|
||||
: gsKts * (hold->timeOrDistance() / 3600.0);
|
||||
|
|
|
|||
|
|
@ -3,11 +3,13 @@ set(TESTSUITE_SOURCES
|
|||
${CMAKE_CURRENT_SOURCE_DIR}/TestSuite.cxx
|
||||
${CMAKE_CURRENT_SOURCE_DIR}/test_flightplan.cxx
|
||||
${CMAKE_CURRENT_SOURCE_DIR}/test_navaids2.cxx
|
||||
${CMAKE_CURRENT_SOURCE_DIR}/test_aircraftPerformance.cxx
|
||||
PARENT_SCOPE
|
||||
)
|
||||
|
||||
set(TESTSUITE_HEADERS
|
||||
${TESTSUITE_HEADERS}
|
||||
${CMAKE_CURRENT_SOURCE_DIR}/test_flightplan.hxx
|
||||
${CMAKE_CURRENT_SOURCE_DIR}/test_aircraftPerformance.hxx
|
||||
PARENT_SCOPE
|
||||
)
|
||||
|
|
|
|||
|
|
@ -19,8 +19,9 @@
|
|||
|
||||
#include "test_flightplan.hxx"
|
||||
#include "test_navaids2.hxx"
|
||||
|
||||
#include "test_aircraftPerformance.hxx"
|
||||
|
||||
// Set up the unit tests.
|
||||
CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(FlightplanTests, "Unit tests");
|
||||
CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(NavaidsTests, "Unit tests");
|
||||
CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(AircraftPerformanceTests, "Unit tests");
|
||||
|
|
|
|||
73
test_suite/unit_tests/Navaids/test_aircraftPerformance.cxx
Normal file
73
test_suite/unit_tests/Navaids/test_aircraftPerformance.cxx
Normal file
|
|
@ -0,0 +1,73 @@
|
|||
#include "test_aircraftPerformance.hxx"
|
||||
|
||||
#include "test_suite/FGTestApi/globals.hxx"
|
||||
#include "test_suite/FGTestApi/NavDataCache.hxx"
|
||||
|
||||
#include <simgear/misc/strutils.hxx>
|
||||
|
||||
#include <Main/fg_props.hxx>
|
||||
#include <Aircraft/AircraftPerformance.hxx>
|
||||
|
||||
using namespace flightgear;
|
||||
|
||||
// Set up function for each test.
|
||||
void AircraftPerformanceTests::setUp()
|
||||
{
|
||||
FGTestApi::setUp::initTestGlobals("aircraft-perf");
|
||||
FGTestApi::setUp::initNavDataCache();
|
||||
}
|
||||
|
||||
|
||||
// Clean up after each test.
|
||||
void AircraftPerformanceTests::tearDown()
|
||||
{
|
||||
FGTestApi::tearDown::shutdownTestGlobals();
|
||||
}
|
||||
|
||||
void AircraftPerformanceTests::testBasic()
|
||||
{
|
||||
fgSetString("/aircraft/performance/icao-category", "C");
|
||||
AircraftPerformance ap;
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.groundSpeedForAltitudeKnots(1000), 152, 1e-3);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.groundSpeedForAltitudeKnots(8000), 224, 1e-3);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.groundSpeedForAltitudeKnots(20000), 491, 1e-3);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.groundSpeedForAltitudeKnots(35000), 461, 1e-3);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.groundSpeedForAltitudeKnots(38000), 458, 1e-3);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.groundSpeedForAltitudeKnots(40000), 458, 1e-3);
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.timeBetween(3000, 6000), 100, 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.distanceNmBetween(3000, 6000), 5.430, 1e-3);
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.timeBetween(36000, 34000), 100, 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.distanceNmBetween(36000, 34000), 12.805, 1e-1);
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.timeBetween(15000, 20000), 300, 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.distanceNmBetween(15000, 18000), 14.270, 1);
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.timeBetween(2000, 25000), 1191.6, 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.distanceNmBetween(2000, 25000), 123.06, 1);
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.timeBetween(36000, 3000), 1666.6, 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(ap.distanceNmBetween(36000, 3000), 162.02, 1);
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(251.5, ap.timeToCruise(32.0, 350000), 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(503.0, ap.timeToCruise(64.0, 380000), 1);
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(1553.7, ap.turnRadiusMForAltitude(4000), 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(3322.4, ap.turnRadiusMForAltitude(16000), 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(4602.6, ap.turnRadiusMForAltitude(30000), 1);
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(4475.5, ap.turnRadiusMForAltitude(38000), 1);
|
||||
}
|
||||
|
||||
void AircraftPerformanceTests::testAltitudeGradient()
|
||||
{
|
||||
fgSetString("/aircraft/performance/icao-category", "E");
|
||||
AircraftPerformance ap;
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(8332, ap.computePreviousAltitude(10000, 6000), 1);
|
||||
|
||||
CPPUNIT_ASSERT_DOUBLES_EQUAL(3260, ap.computeNextAltitude(4000, 2000), 1);
|
||||
|
||||
|
||||
}
|
||||
|
||||
49
test_suite/unit_tests/Navaids/test_aircraftPerformance.hxx
Normal file
49
test_suite/unit_tests/Navaids/test_aircraftPerformance.hxx
Normal file
|
|
@ -0,0 +1,49 @@
|
|||
/*
|
||||
* Copyright (C) 2018 James Turner
|
||||
*
|
||||
* This file is part of the program FlightGear.
|
||||
*
|
||||
* This program is free software: you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation, either version 2 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
*/
|
||||
|
||||
|
||||
#ifndef _FG_AIRCRAFT_PERFORMANCE_UNIT_TESTS_HXX
|
||||
#define _FG_AIRCRAFT_PERFORMANCE_UNIT_TESTS_HXX
|
||||
|
||||
|
||||
#include <cppunit/extensions/HelperMacros.h>
|
||||
#include <cppunit/TestFixture.h>
|
||||
|
||||
|
||||
class AircraftPerformanceTests : public CppUnit::TestFixture
|
||||
{
|
||||
// Set up the test suite.
|
||||
CPPUNIT_TEST_SUITE(AircraftPerformanceTests);
|
||||
CPPUNIT_TEST(testBasic);
|
||||
CPPUNIT_TEST(testAltitudeGradient);
|
||||
CPPUNIT_TEST_SUITE_END();
|
||||
|
||||
public:
|
||||
// Set up function for each test.
|
||||
void setUp();
|
||||
|
||||
// Clean up after each test.
|
||||
void tearDown();
|
||||
|
||||
// The tests.
|
||||
void testBasic();
|
||||
void testAltitudeGradient();
|
||||
};
|
||||
|
||||
#endif // AircraftPerformanceTests
|
||||
Loading…
Reference in a new issue