1 // FGAIBallistic - FGAIBase-derived class creates a ballistic object
3 // Written by David Culp, started November 2003.
4 // - davidculp2@comcast.net
6 // With major additions by Mathias Froehlich & Vivian Meazza 2004-2008
8 // This program is free software; you can redistribute it and/or
9 // modify it under the terms of the GNU General Public License as
10 // published by the Free Software Foundation; either version 2 of the
11 // License, or (at your option) any later version.
13 // This program is distributed in the hope that it will be useful, but
14 // WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 // General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
26 #include <simgear/math/sg_random.h>
27 #include <simgear/math/sg_geodesy.hxx>
28 #include <simgear/scene/model/modellib.hxx>
30 #include <Scenery/scenery.hxx>
32 #include "AIBallistic.hxx"
34 #include <Main/util.hxx>
36 using namespace simgear;
38 const double FGAIBallistic::slugs_to_kgs = 14.5939029372;
39 const double FGAIBallistic::slugs_to_lbs = 32.1740485564;
41 FGAIBallistic::FGAIBallistic(object_type ot) :
48 _formate_to_ac(false),
49 _aero_stabilised(false),
52 _gravity(32.1740485564),
59 _force_stabilised(false),
61 _slave_load_to_ac(false),
63 _report_collision(false),
64 _report_expiry(false),
65 _report_impact(false),
66 _external_force(false),
67 _impact_report_node(fgGetNode("/ai/models/model-impact", true)),
76 FGAIBallistic::~FGAIBallistic() {
79 void FGAIBallistic::readFromScenario(SGPropertyNode* scFileNode) {
84 FGAIBase::readFromScenario(scFileNode);
86 //setPath(scFileNode->getStringValue("model", "Models/Geometry/rocket.ac"));
87 setRandom(scFileNode->getBoolValue("random", false));
88 setAzimuth(scFileNode->getDoubleValue("azimuth", 0.0));
89 setElevation(scFileNode->getDoubleValue("elevation", 0));
90 setDragArea(scFileNode->getDoubleValue("eda", 0.007));
91 setLife(scFileNode->getDoubleValue("life", 900.0));
92 setBuoyancy(scFileNode->getDoubleValue("buoyancy", 0));
93 //setWind_from_east(scFileNode->getDoubleValue("wind_from_east", 0));
94 //setWind_from_north(scFileNode->getDoubleValue("wind_from_north", 0));
95 setWind(scFileNode->getBoolValue("wind", false));
96 setRoll(scFileNode->getDoubleValue("roll", 0.0));
97 setCd(scFileNode->getDoubleValue("cd", 0.029));
98 //setMass(scFileNode->getDoubleValue("mass", 0.007));
99 setWeight(scFileNode->getDoubleValue("weight", 0.25));
100 setStabilisation(scFileNode->getBoolValue("aero-stabilised", false));
101 setNoRoll(scFileNode->getBoolValue("no-roll", false));
102 setImpact(scFileNode->getBoolValue("impact", false));
103 setExpiry(scFileNode->getBoolValue("expiry", false));
104 setCollision(scFileNode->getBoolValue("collision", false));
105 setImpactReportNode(scFileNode->getStringValue("impact-reports"));
106 setName(scFileNode->getStringValue("name", "Rocket"));
107 setFuseRange(scFileNode->getDoubleValue("fuse-range", 0.0));
108 setSMPath(scFileNode->getStringValue("submodel-path", ""));
109 setSubID(scFileNode->getIntValue("SubID", 0));
110 setExternalForce(scFileNode->getBoolValue("external-force", false));
111 setForcePath(scFileNode->getStringValue("force-path", ""));
112 setForceStabilisation(scFileNode->getBoolValue("force-stabilised", false));
113 setXoffset(scFileNode->getDoubleValue("x-offset", 0.0));
114 setYoffset(scFileNode->getDoubleValue("y-offset", 0.0));
115 setZoffset(scFileNode->getDoubleValue("z-offset", 0.0));
116 setPitchoffset(scFileNode->getDoubleValue("pitch-offset", 0.0));
117 setRolloffset(scFileNode->getDoubleValue("roll-offset", 0.0));
118 setYawoffset(scFileNode->getDoubleValue("yaw-offset", 0.0));
119 setGroundOffset(scFileNode->getDoubleValue("ground-offset", 0.0));
120 setLoadOffset(scFileNode->getDoubleValue("load-offset", 0.0));
121 setSlaved(scFileNode->getBoolValue("slaved", false));
122 setSlavedLoad(scFileNode->getBoolValue("slaved-load", false));
123 setContentsPath(scFileNode->getStringValue("contents"));
124 setParentName(scFileNode->getStringValue("parent"));
127 bool FGAIBallistic::init(bool search_in_AI_path) {
128 FGAIBase::init(search_in_AI_path);
130 _impact_reported = false;
131 _collision_reported = false;
132 _expiry_reported = false;
144 _elapsed_time += (sg_random() * 100);
146 props->setStringValue("material/name", "");
147 props->setStringValue("name", _name.c_str());
148 props->setStringValue("submodels/path", _path.c_str());
151 props->setStringValue("force/path", _force_path.c_str());
152 props->setStringValue("contents/path", _contents_path.c_str());
159 setParentNodes(_selected_ac);
160 //props->setStringValue("vector/path", _vector_path.c_str());
162 // start with high value so that animations don't trigger yet
170 //cout << _name << " speed init: " << speed << endl;
175 void FGAIBallistic::bind() {
178 props->tie("sim/time/elapsed-sec",
179 SGRawValueMethods<FGAIBallistic,double>(*this,
180 &FGAIBallistic::_getTime));
181 //props->tie("mass-slug",
182 // SGRawValueMethods<FGAIBallistic,double>(*this,
183 // &FGAIBallistic::getMass));
185 props->tie("material/solid",
186 SGRawValuePointer<bool>(&_solid));
187 props->tie("altitude-agl-ft",
188 SGRawValuePointer<double>(&_ht_agl_ft));
189 props->tie("controls/slave-to-ac",
190 SGRawValueMethods<FGAIBallistic,bool>
191 (*this, &FGAIBallistic::getSlaved, &FGAIBallistic::setSlaved));
192 props->tie("controls/invisible",
193 SGRawValuePointer<bool>(&invisible));
195 if(_external_force || _slave_to_ac){
196 props->tie("controls/force_stabilized",
197 SGRawValuePointer<bool>(&_force_stabilised));
198 props->tie("position/global-x",
199 SGRawValueMethods<FGAIBase,double>(*this, &FGAIBase::_getCartPosX, 0));
200 props->tie("position/global-y",
201 SGRawValueMethods<FGAIBase,double>(*this, &FGAIBase::_getCartPosY, 0));
202 props->tie("position/global-z",
203 SGRawValueMethods<FGAIBase,double>(*this, &FGAIBase::_getCartPosZ, 0));
204 props->tie("velocities/vertical-speed-fps",
205 SGRawValuePointer<double>(&vs));
206 props->tie("velocities/true-airspeed-kt",
207 SGRawValuePointer<double>(&speed));
208 props->tie("velocities/horizontal-speed-fps",
209 SGRawValuePointer<double>(&hs));
210 props->tie("position/altitude-ft",
211 SGRawValueMethods<FGAIBase,double>(*this, &FGAIBase::_getElevationFt, &FGAIBase::_setAltitude));
212 props->tie("position/latitude-deg",
213 SGRawValueMethods<FGAIBase,double>(*this, &FGAIBase::_getLatitude, &FGAIBase::_setLatitude));
214 props->tie("position/longitude-deg",
215 SGRawValueMethods<FGAIBase,double>(*this, &FGAIBase::_getLongitude, &FGAIBase::_setLongitude));
216 props->tie("orientation/hdg-deg",
217 SGRawValuePointer<double>(&hdg));
218 props->tie("orientation/pitch-deg",
219 SGRawValuePointer<double>(&pitch));
220 props->tie("orientation/roll-deg",
221 SGRawValuePointer<double>(&roll));
222 props->tie("controls/slave-load-to-ac",
223 SGRawValueMethods<FGAIBallistic,bool>
224 (*this, &FGAIBallistic::getSlavedLoad, &FGAIBallistic::setSlavedLoad));
225 props->tie("position/load-offset",
226 SGRawValueMethods<FGAIBallistic,double>
227 (*this, &FGAIBallistic::getLoadOffset, &FGAIBallistic::setLoadOffset));
228 props->tie("load/distance-to-hitch-ft",
229 SGRawValueMethods<FGAIBallistic,double>
230 (*this, &FGAIBallistic::getDistanceLoadToHitch));
231 props->tie("load/elevation-to-hitch-deg",
232 SGRawValueMethods<FGAIBallistic,double>
233 (*this, &FGAIBallistic::getElevLoadToHitch));
234 props->tie("load/bearing-to-hitch-deg",
235 SGRawValueMethods<FGAIBallistic,double>
236 (*this, &FGAIBallistic::getBearingLoadToHitch));
237 props->tie("material/load-resistance",
238 SGRawValuePointer<double>(&_load_resistance));
243 void FGAIBallistic::unbind() {
244 // FGAIBase::unbind();
246 props->untie("sim/time/elapsed-sec");
247 props->untie("mass-slug");
248 props->untie("material/solid");
249 props->untie("altitude-agl-ft");
250 props->untie("controls/slave-to-ac");
251 props->untie("controls/invisible");
253 if(_external_force || _slave_to_ac){
254 props->untie("position/global-y");
255 props->untie("position/global-x");
256 props->untie("position/global-z");
257 props->untie("velocities/vertical-speed-fps");
258 props->untie("velocities/true-airspeed-kt");
259 props->untie("velocities/horizontal-speed-fps");
260 props->untie("position/altitude-ft");
261 props->untie("position/latitude-deg");
262 props->untie("position/longitude-deg");
263 props->untie("position/ht-agl-ft");
264 props->untie("orientation/hdg-deg");
265 props->untie("orientation/pitch-deg");
266 props->untie("orientation/roll-deg");
267 props->untie("controls/force_stabilized");
268 props->untie("position/load-offset");
269 props->untie("load/distance-to-hitch-ft");
270 props->untie("load/elevation-to-hitch-deg");
271 props->untie("load/bearing-to-hitch-deg");
272 props->untie("material/load-resistance");
276 void FGAIBallistic::update(double dt) {
277 FGAIBase::update(dt);
283 } else if (_slave_to_ac){
286 } else if (!invisible){
293 void FGAIBallistic::setAzimuth(double az) {
296 hdg = _azimuth = (az - 5 ) + (10 * sg_random());
300 //cout << _name << " init hdg " << hdg << " random " << _random << endl;
303 void FGAIBallistic::setElevation(double el) {
304 pitch = _elevation = el;
307 void FGAIBallistic::setRoll(double rl) {
308 roll = _rotation = rl;
311 void FGAIBallistic::setStabilisation(bool val) {
312 _aero_stabilised = val;
315 void FGAIBallistic::setForceStabilisation(bool val) {
316 _force_stabilised = val;
319 void FGAIBallistic::setNoRoll(bool nr) {
323 void FGAIBallistic::setDragArea(double a) {
327 void FGAIBallistic::setLife(double seconds) {
330 life = seconds * _randomness + (seconds * (1 -_randomness) * sg_random());
331 //cout << "life " << life << endl;
336 void FGAIBallistic::setBuoyancy(double fpss) {
340 void FGAIBallistic::setWind_from_east(double fps) {
341 _wind_from_east = fps;
344 void FGAIBallistic::setWind_from_north(double fps) {
345 _wind_from_north = fps;
348 void FGAIBallistic::setWind(bool val) {
352 void FGAIBallistic::setCd(double c) {
356 void FGAIBallistic::setMass(double m) {
360 void FGAIBallistic::setWeight(double w) {
364 void FGAIBallistic::setRandomness(double r) {
368 void FGAIBallistic::setRandom(bool r) {
372 void FGAIBallistic::setImpact(bool i) {
376 void FGAIBallistic::setCollision(bool c) {
377 _report_collision = c;
380 void FGAIBallistic::setExpiry(bool e) {
384 void FGAIBallistic::setExternalForce(bool f) {
388 void FGAIBallistic::setImpactReportNode(const string& path) {
391 _impact_report_node = fgGetNode(path.c_str(), true);
394 void FGAIBallistic::setName(const string& n) {
398 void FGAIBallistic::setSMPath(const string& s) {
400 //cout << "submodel path " << _path << endl;
403 void FGAIBallistic::setFuseRange(double f) {
407 void FGAIBallistic::setSubID(int i) {
411 void FGAIBallistic::setSubmodel(const string& s) {
415 void FGAIBallistic::setGroundOffset(double g) {
419 void FGAIBallistic::setLoadOffset(double l) {
423 double FGAIBallistic::getLoadOffset() const {
427 void FGAIBallistic::setSlaved(bool s) {
431 void FGAIBallistic::setFormate(bool f) {
435 void FGAIBallistic::setContentsPath(const string& path) {
437 _contents_path = path;
440 _contents_node = fgGetNode(path.c_str(), true);
444 void FGAIBallistic::setContentsNode(SGPropertyNode_ptr node) {
447 _contents_node = node;
448 _contents_path = _contents_node->getDisplayName();
452 void FGAIBallistic::setParentNodes(SGPropertyNode_ptr node) {
456 _p_pos_node = _pnode->getChild("position", 0, true);
457 _p_lat_node = _p_pos_node->getChild("latitude-deg", 0, true);
458 _p_lon_node = _p_pos_node->getChild("longitude-deg", 0, true);
459 _p_alt_node = _p_pos_node->getChild("altitude-ft", 0, true);
461 _p_ori_node = _pnode->getChild("orientation", 0, true);
462 _p_pch_node = _p_ori_node->getChild("pitch-deg", 0, true);
463 _p_rll_node = _p_ori_node->getChild("roll-deg", 0, true);
464 _p_hdg_node = _p_ori_node->getChild("true-heading-deg",0, true);
466 _p_vel_node = _pnode->getChild("velocities", 0, true);
467 _p_spd_node = _p_vel_node->getChild("true-airspeed-kt", 0, true);
472 void FGAIBallistic::setParentPos() {
475 double lat = _p_lat_node->getDoubleValue();
476 double lon = _p_lon_node->getDoubleValue();
477 double alt = _p_alt_node->getDoubleValue();
479 _parentpos.setLongitudeDeg(lon);
480 _parentpos.setLatitudeDeg(lat);
481 _parentpos.setElevationFt(alt);
486 bool FGAIBallistic::getSlaved() const {
490 bool FGAIBallistic::getFormate() const {
491 return _formate_to_ac;
494 double FGAIBallistic::getMass() const {
498 double FGAIBallistic::getContents() {
500 _contents_lb = _contents_node->getChild("level-lbs",0,1)->getDoubleValue();
505 void FGAIBallistic::setContents(double c) {
507 _contents_lb = _contents_node->getChild("level-gal_us",0,1)->setDoubleValue(c);
510 void FGAIBallistic::setSlavedLoad(bool l) {
511 _slave_load_to_ac = l;
514 bool FGAIBallistic::getSlavedLoad() const {
515 return _slave_load_to_ac;
518 void FGAIBallistic::setForcePath(const string& p) {
520 if (!_force_path.empty()) {
521 SGPropertyNode *fnode = fgGetNode(_force_path.c_str(), 0, true );
522 _force_node = fnode->getChild("force-lb", 0, true);
523 _force_azimuth_node = fnode->getChild("force-azimuth-deg", 0, true);
524 _force_elevation_node = fnode->getChild("force-elevation-deg", 0, true);
528 bool FGAIBallistic::getHtAGL(double start){
530 if (getGroundElevationM(SGGeod::fromGeodM(pos, start),
531 _elevation_m, &_material)) {
532 _ht_agl_ft = pos.getElevationFt() - _elevation_m * SG_METER_TO_FEET;
535 const vector<string>& names = _material->get_names();
536 _solid = _material->get_solid();
537 _load_resistance = _material->get_load_resistance();
538 _frictionFactor =_material->get_friction_factor();
541 props->setStringValue("material/name", names[0].c_str());
543 props->setStringValue("material/name", "");
545 _mat_name = names[0];
547 //cout << "material " << _mat_name
548 //<< " solid " << _solid
549 //<< " load " << _load_resistance
550 //<< " frictionFactor " << _frictionFactor
562 double FGAIBallistic::getRecip(double az){
563 // calculate the reciprocal of the input azimuth
571 void FGAIBallistic::setPch(double e, double dt, double coeff){
572 double c = dt / (coeff + dt);
573 pitch = (e * c) + (pitch * (1 - c));
576 void FGAIBallistic::setBnk(double r, double dt, double coeff){
577 double c = dt / (coeff + dt);
578 roll = (r * c) + (roll * (1 - c));
581 void FGAIBallistic::setHt(double h, double dt, double coeff){
582 double c = dt / (coeff + dt);
583 _height = (h * c) + (_height * (1 - c));
586 void FGAIBallistic::setHdg(double az, double dt, double coeff){
587 double recip = getRecip(hdg);
588 double c = dt / (coeff + dt);
589 //we need to ensure that we turn the short way to the new hdg
590 if (az < recip && az < hdg && hdg > 180) {
591 hdg = ((az + 360) * c) + (hdg * (1 - c));
592 } else if (az > recip && az > hdg && hdg <= 180){
593 hdg = ((az - 360) * c) + (hdg * (1 - c));
595 hdg = (az * c) + (hdg * (1 - c));
599 double FGAIBallistic::getTgtXOffset() const {
600 return _tgt_x_offset;
603 double FGAIBallistic::getTgtYOffset() const {
604 return _tgt_y_offset;
607 double FGAIBallistic::getTgtZOffset() const {
608 return _tgt_z_offset;
611 void FGAIBallistic::setTgtXOffset(double x){
615 void FGAIBallistic::setTgtYOffset(double y){
619 void FGAIBallistic::setTgtZOffset(double z){
623 void FGAIBallistic::slaveToAC(double dt){
625 double hdg, pch, rll = 0;
629 hdg = _p_hdg_node->getDoubleValue();
630 pch = _p_pch_node->getDoubleValue();
631 rll = _p_rll_node->getDoubleValue();
632 setOffsetPos(_parentpos, hdg, pch, rll);
633 setSpeed(_p_spd_node->getDoubleValue());
635 hdg = manager->get_user_heading();
636 pch = manager->get_user_pitch();
637 rll = manager->get_user_roll();
638 setOffsetPos(userpos, hdg, pch, rll);
639 setSpeed(manager->get_user_speed());
642 pos.setLatitudeDeg(_offsetpos.getLatitudeDeg());
643 pos.setLongitudeDeg(_offsetpos.getLongitudeDeg());
644 pos.setElevationFt(_offsetpos.getElevationFt());
646 setPitch(pch + _pitch_offset);
647 setBank(rll + _roll_offset);
648 setOffsetVelocity(dt, pos);
650 //update the mass (slugs)
651 _mass = (_weight_lb + getContents()) / slugs_to_lbs;
653 _impact_reported = false;
655 //cout << _name << " _mass "<<_mass <<" " << getContents()
656 //<< " " << getContents() / slugs_to_lbs << " weight " << _weight_lb << endl;
657 // cout << _name << " update hs " << hs << " vs " << vs << endl;
660 void FGAIBallistic::Run(double dt) {
663 // if life = -1 the object does not die
664 if (_life_timer > life && life != -1){
666 if (_report_expiry && !_expiry_reported && !_impact_reported && !_collision_reported){
667 //cout<<"AIBallistic: expiry"<< endl;
674 //set the contents in the appropriate tank or other property in the parent to zero
677 //randomise Cd by +- 10%
679 _Cd = _Cd * 0.90 + (0.10 * sg_random());
681 // Adjust Cd by Mach number. The equations are based on curves
682 // for a conventional shell/bullet (no boat-tail).
686 Cdm = 0.0125 * Mach + _Cd;
687 else if (Mach < 1.2 )
688 Cdm = 0.3742 * pow(Mach, 2) - 0.252 * Mach + 0.0021 + _Cd;
690 Cdm = 0.2965 * pow(Mach, -1.1506) + _Cd;
692 //cout <<_name << " Mach " << Mach << " Cdm " << Cdm
693 // << " ballistic speed kts "<< speed << endl;
695 // drag = Cd * 0.5 * rho * speed * speed * drag_area;
696 // rho is adjusted for altitude in void FGAIBase::update,
697 // using Standard Atmosphere (sealevel temperature 15C)
698 // acceleration = drag/mass;
699 // adjust speed by drag
700 speed -= (Cdm * 0.5 * rho * speed * speed * _drag_area/_mass) * dt;
702 // don't let speed become negative
706 double speed_fps = speed * SG_KT_TO_FPS;
709 // calculate vertical and horizontal speed components
713 vs = sin( _elevation * SG_DEGREES_TO_RADIANS ) * speed_fps;
714 hs = cos( _elevation * SG_DEGREES_TO_RADIANS ) * speed_fps;
717 //resolve horizontal speed into north and east components:
718 double speed_north_fps = cos(_azimuth / SG_RADIANS_TO_DEGREES) * hs;
719 double speed_east_fps = sin(_azimuth / SG_RADIANS_TO_DEGREES) * hs;
721 // convert horizontal speed (fps) to degrees per second
722 double speed_north_deg_sec = speed_north_fps / ft_per_deg_lat;
723 double speed_east_deg_sec = speed_east_fps / ft_per_deg_lon;
725 // if wind not required, set to zero
727 _wind_from_north = 0;
730 _wind_from_north = manager->get_wind_from_north();
731 _wind_from_east = manager->get_wind_from_east();
734 //calculate velocity due to external force
735 double force_speed_north_deg_sec = 0;
736 double force_speed_east_deg_sec = 0;
737 // double vs_force_fps = 0;
738 double hs_force_fps = 0;
739 double v_force_acc_fpss = 0;
740 double force_speed_north_fps = 0;
741 double force_speed_east_fps = 0;
742 double h_force_lbs = 0;
743 double normal_force_lbs = 0;
744 double normal_force_fpss = 0;
745 double static_friction_force_lbs = 0;
746 double dynamic_friction_force_lbs = 0;
747 double friction_force_speed_north_fps = 0;
748 double friction_force_speed_east_fps = 0;
749 double friction_force_speed_north_deg_sec = 0;
750 double friction_force_speed_east_deg_sec = 0;
751 double force_elevation_deg = 0;
753 if (_external_force) {
754 //cout << _name << " external force" << endl;
756 SGPropertyNode *n = fgGetNode(_force_path.c_str(), true);
757 double force_lbs = n->getChild("force-lb", 0, true)->getDoubleValue();
758 force_elevation_deg = n->getChild("force-elevation-deg", 0, true)->getDoubleValue();
759 double force_azimuth_deg = n->getChild("force-azimuth-deg", 0, true)->getDoubleValue();
761 //resolve force into vertical and horizontal components:
762 double v_force_lbs = force_lbs * sin( force_elevation_deg * SG_DEGREES_TO_RADIANS );
763 h_force_lbs = force_lbs * cos( force_elevation_deg * SG_DEGREES_TO_RADIANS );
767 if (getHtAGL(10000)){
768 double deadzone = 0.1;
770 if (_ht_agl_ft <= (0 + _ground_offset + deadzone) && _solid){
771 normal_force_lbs = (_mass * slugs_to_lbs) - v_force_lbs;
773 if ( normal_force_lbs < 0 )
774 normal_force_lbs = 0;
776 pos.setElevationFt(0 + _ground_offset);
780 // calculate friction
781 // we assume a static Coefficient of Friction (mu) of 0.62 (wood on concrete)
784 static_friction_force_lbs = mu * normal_force_lbs * _frictionFactor;
786 //adjust horizontal force. We assume that a speed of <= 5 fps is static
787 if (h_force_lbs <= static_friction_force_lbs && hs <= 5){
788 h_force_lbs = hs = 0;
789 speed_north_fps = speed_east_fps = 0;
791 dynamic_friction_force_lbs = (static_friction_force_lbs * 0.95);
793 //ignore wind when on the ground for now
795 _wind_from_north = 0;
802 //acceleration = (force(lbsf)/mass(slugs))
803 v_force_acc_fpss = v_force_lbs/_mass;
804 normal_force_fpss = normal_force_lbs/_mass;
805 double h_force_acc_fpss = h_force_lbs/_mass;
806 double dynamic_friction_acc_fpss = dynamic_friction_force_lbs/_mass;
808 // velocity = acceleration * dt
809 hs_force_fps = h_force_acc_fpss * dt;
810 double friction_force_fps = dynamic_friction_acc_fpss * dt;
812 //resolve horizontal speeds into north and east components:
813 force_speed_north_fps = cos(force_azimuth_deg * SG_DEGREES_TO_RADIANS) * hs_force_fps;
814 force_speed_east_fps = sin(force_azimuth_deg * SG_DEGREES_TO_RADIANS) * hs_force_fps;
816 friction_force_speed_north_fps = cos(getRecip(hdg) * SG_DEGREES_TO_RADIANS) * friction_force_fps;
817 friction_force_speed_east_fps = sin(getRecip(hdg) * SG_DEGREES_TO_RADIANS) * friction_force_fps;
819 // convert horizontal speed (fps) to degrees per second
820 force_speed_north_deg_sec = force_speed_north_fps / ft_per_deg_lat;
821 force_speed_east_deg_sec = force_speed_east_fps / ft_per_deg_lon;
823 friction_force_speed_north_deg_sec = friction_force_speed_north_fps / ft_per_deg_lat;
824 friction_force_speed_east_deg_sec = friction_force_speed_east_fps / ft_per_deg_lon;
827 // convert wind speed (fps) to degrees lat/lon per second
828 double wind_speed_from_north_deg_sec = _wind_from_north / ft_per_deg_lat;
829 double wind_speed_from_east_deg_sec = _wind_from_east / ft_per_deg_lon;
831 //recombine the horizontal velocity components
832 hs = sqrt(((speed_north_fps + force_speed_north_fps + friction_force_speed_north_fps)
833 * (speed_north_fps + force_speed_north_fps + friction_force_speed_north_fps))
834 + ((speed_east_fps + force_speed_east_fps + friction_force_speed_east_fps)
835 * (speed_east_fps + force_speed_east_fps + friction_force_speed_east_fps)));
840 // adjust vertical speed for acceleration of gravity, buoyancy, and vertical force
841 vs -= (_gravity - _buoyancy - v_force_acc_fpss - normal_force_fpss) * dt;
843 if (vs <= 0.00001 && vs >= -0.00001)
847 if(_slave_load_to_ac) {
849 manager->get_user_heading(),
850 manager->get_user_pitch(),
851 manager->get_user_roll()
853 pos.setLatitudeDeg(_offsetpos.getLatitudeDeg());
854 pos.setLongitudeDeg(_offsetpos.getLongitudeDeg());
855 pos.setElevationFt(_offsetpos.getElevationFt());
857 if (getHtAGL(10000)){
858 double deadzone = 0.1;
860 if (_ht_agl_ft <= (0 + _ground_offset + deadzone) && _solid){
861 pos.setElevationFt(0 + _ground_offset);
863 pos.setElevationFt(_offsetpos.getElevationFt() + _load_offset);
868 pos.setLatitudeDeg( pos.getLatitudeDeg()
869 + (speed_north_deg_sec - wind_speed_from_north_deg_sec
870 + force_speed_north_deg_sec + friction_force_speed_north_deg_sec) * dt );
871 pos.setLongitudeDeg( pos.getLongitudeDeg()
872 + (speed_east_deg_sec - wind_speed_from_east_deg_sec
873 + force_speed_east_deg_sec + friction_force_speed_east_deg_sec) * dt );
874 pos.setElevationFt(pos.getElevationFt() + vs * dt);
877 // cout << _name << " run hs " << hs << " vs " << vs << endl;
879 // recalculate total speed
880 if ( vs == 0 && hs == 0)
883 speed = sqrt( vs * vs + hs * hs) / SG_KT_TO_FPS;
885 // recalculate elevation and azimuth (velocity vectors)
886 _elevation = atan2( vs, hs ) * SG_RADIANS_TO_DEGREES;
887 _azimuth = atan2((speed_east_fps + force_speed_east_fps + friction_force_speed_east_fps),
888 (speed_north_fps + force_speed_north_fps + friction_force_speed_north_fps))
889 * SG_RADIANS_TO_DEGREES;
891 // rationalise azimuth
895 if (_aero_stabilised) { // we simulate rotational moment of inertia by using a filter
896 //cout<< "_aero_stabilised "<< endl;
897 const double coeff = 0.9;
899 // we assume a symetrical MI about the pitch and yaw axis
900 setPch(_elevation, dt, coeff);
901 setHdg(_azimuth, dt, coeff);
902 } else if (_force_stabilised) { // we simulate rotational moment of inertia by using a filter
903 //cout<< "_force_stabilised "<< endl;
905 const double coeff = 0.9;
906 double ratio = h_force_lbs/(_mass * slugs_to_lbs);
908 if (ratio > 1) ratio = 1;
909 if (ratio < -1) ratio = -1;
911 double force_pitch = acos(ratio) * SG_RADIANS_TO_DEGREES;
913 if (force_pitch <= force_elevation_deg)
914 force_pitch = force_elevation_deg;
916 // we assume a symetrical MI about the pitch and yaw axis
917 setPch(force_pitch,dt, coeff);
918 setHdg(_azimuth, dt, coeff);
921 //do impacts and collisions
922 if (_report_impact && !_impact_reported)
925 if (_report_collision && !_collision_reported)
928 // set destruction flag if altitude less than sea level -1000
929 if (altitude_ft < -1000.0 && life != -1)
934 double FGAIBallistic::_getTime() const {
938 void FGAIBallistic::handle_impact() {
940 // try terrain intersection
941 double start = pos.getElevationM() + 10;
946 if (_ht_agl_ft <= 0) {
947 SG_LOG(SG_GENERAL, SG_DEBUG, "AIBallistic: terrain impact");
948 report_impact(_elevation_m);
949 _impact_reported = true;
953 } else if (_subID == 0) // kill the AIObject if there is no subsubmodel
958 void FGAIBallistic::handle_expiry() {
960 SG_LOG(SG_GENERAL, SG_DEBUG, "AIBallistic: handle_expiry " << pos.getElevationM());
962 report_impact(pos.getElevationM());
963 _expiry_reported = true;
967 } else if (_subID == 0){ // kill the AIObject if there is no subsubmodel
973 void FGAIBallistic::handle_collision()
975 const FGAIBase *object = manager->calcCollision(pos.getElevationFt(),
976 pos.getLatitudeDeg(),pos.getLongitudeDeg(), _fuse_range);
979 report_impact(pos.getElevationM(), object);
980 _collision_reported = true;
984 void FGAIBallistic::report_impact(double elevation, const FGAIBase *object)
986 _impact_lat = pos.getLatitudeDeg();
987 _impact_lon = pos.getLongitudeDeg();
988 _impact_elev = elevation;
989 _impact_speed = speed * SG_KT_TO_MPS;
991 _impact_pitch = pitch;
994 SGPropertyNode *n = props->getNode("impact", true);
997 n->setStringValue("type", object->getTypeString());
999 n->setStringValue("type", "terrain");
1001 SG_LOG(SG_GENERAL, SG_DEBUG, "AIBallistic: object impact" << _name << " lon " <<_impact_lon);
1003 n->setDoubleValue("longitude-deg", _impact_lon);
1004 n->setDoubleValue("latitude-deg", _impact_lat);
1005 n->setDoubleValue("elevation-m", _impact_elev);
1006 n->setDoubleValue("heading-deg", _impact_hdg);
1007 n->setDoubleValue("pitch-deg", _impact_pitch);
1008 n->setDoubleValue("roll-deg", _impact_roll);
1009 n->setDoubleValue("speed-mps", _impact_speed);
1011 _impact_report_node->setStringValue(props->getPath());
1014 SGVec3d FGAIBallistic::getCartUserPos() const {
1015 SGVec3d cartUserPos = SGVec3d::fromGeod(userpos);
1019 SGVec3d FGAIBallistic::getCartHitchPos() const{
1021 // convert geodetic positions to geocentered
1022 SGVec3d cartuserPos = SGVec3d::fromGeod(userpos);
1023 //SGVec3d cartPos = getCartPos();
1025 // Transform to the right coordinate frame, configuration is done in
1026 // the x-forward, y-right, z-up coordinates (feet), computation
1027 // in the simulation usual body x-forward, y-right, z-down coordinates
1029 SGVec3d _off(_x_offset * SG_FEET_TO_METER,
1030 _y_offset * SG_FEET_TO_METER,
1031 -_z_offset * SG_FEET_TO_METER);
1033 // Transform the user position to the horizontal local coordinate system.
1034 SGQuatd hlTrans = SGQuatd::fromLonLat(userpos);
1036 // and postrotate the orientation of the user model wrt the horizontal
1038 hlTrans *= SGQuatd::fromYawPitchRollDeg(
1039 manager->get_user_heading(),
1040 manager->get_user_pitch(),
1041 manager->get_user_roll());
1043 // The offset converted to the usual body fixed coordinate system
1044 // rotated to the earth-fixed coordinates axis
1045 SGVec3d off = hlTrans.backTransform(_off);
1047 // Add the position offset of the user model to get the geocentered position
1048 SGVec3d offsetPos = cartuserPos + off;
1053 void FGAIBallistic::setOffsetPos(SGGeod inpos, double heading, double pitch, double roll){
1054 // convert the hitch geocentered position to geodetic
1056 SGVec3d cartoffsetPos = getCartOffsetPos(inpos, heading, pitch, roll);
1058 //SGVec3d cartoffsetPos = getCartHitchPos();
1060 //SGGeodesy::SGCartToGeod(cartoffsetPos, hitchpos);
1061 SGGeodesy::SGCartToGeod(cartoffsetPos, _offsetpos);
1065 double FGAIBallistic::getDistanceLoadToHitch() const {
1066 //calculate the distance load to hitch
1067 SGVec3d carthitchPos = getCartHitchPos();
1068 SGVec3d cartPos = getCartPos();
1070 SGVec3d diff = carthitchPos - cartPos;
1071 double distance = norm(diff);
1072 return distance * SG_METER_TO_FEET;
1076 double FGAIBallistic::getElevLoadToHitch() const {
1077 // now the angle, positive angles are upwards
1078 double distance = getDistanceLoadToHitch() * SG_FEET_TO_METER;
1080 double daltM = _offsetpos.getElevationM() - pos.getElevationM();
1082 if (fabs(distance) < SGLimits<float>::min()) {
1085 double sAngle = daltM/distance;
1086 sAngle = SGMiscd::min(1, SGMiscd::max(-1, sAngle));
1087 angle = SGMiscd::rad2deg(asin(sAngle));
1093 double FGAIBallistic::getBearingLoadToHitch() const {
1094 //calculate the bearing and range of the second pos from the first
1095 double az1, az2, distance;
1097 geo_inverse_wgs_84(pos, _offsetpos, &az1, &az2, &distance);
1102 double FGAIBallistic::getRelBrgHitchToUser() const {
1103 //calculate the relative bearing
1104 double az1, az2, distance;
1106 geo_inverse_wgs_84(_offsetpos, userpos, &az1, &az2, &distance);
1108 double rel_brg = az1 - hdg;
1116 double FGAIBallistic::getElevHitchToUser() const {
1118 //calculate the distance from the user position
1119 SGVec3d carthitchPos = getCartHitchPos();
1120 SGVec3d cartuserPos = getCartUserPos();
1122 SGVec3d diff = cartuserPos - carthitchPos;
1124 double distance = norm(diff);
1127 double daltM = userpos.getElevationM() - _offsetpos.getElevationM();
1129 // now the angle, positive angles are upwards
1130 if (fabs(distance) < SGLimits<float>::min()) {
1133 double sAngle = daltM/distance;
1134 sAngle = SGMiscd::min(1, SGMiscd::max(-1, sAngle));
1135 angle = SGMiscd::rad2deg(asin(sAngle));
1141 void FGAIBallistic::setTgtOffsets(double dt, double coeff){
1142 double c = dt / (coeff + dt);
1144 _x_offset = (_tgt_x_offset * c) + (_x_offset * (1 - c));
1145 _y_offset = (_tgt_y_offset * c) + (_y_offset * (1 - c));
1146 _z_offset = (_tgt_z_offset * c) + (_z_offset * (1 - c));
1149 void FGAIBallistic::formateToAC(double dt){
1151 double hdg, pch, rll = 0;
1153 setTgtOffsets(dt, 25);
1157 hdg = _p_hdg_node->getDoubleValue();
1158 pch = _p_pch_node->getDoubleValue();
1159 rll = _p_rll_node->getDoubleValue();
1160 setOffsetPos(_parentpos, hdg, pch, rll);
1161 setSpeed(_p_spd_node->getDoubleValue());
1163 hdg = manager->get_user_heading();
1164 pch = manager->get_user_pitch();
1165 rll = manager->get_user_roll();
1166 setOffsetPos(userpos, hdg, pch, rll);
1167 setSpeed(manager->get_user_speed());
1170 // elapsed time has a random initialisation so that each
1171 // wingman moves differently
1172 _elapsed_time += dt;
1174 // we derive a sine based factor to give us smoothly
1175 // varying error between -1 and 1
1176 double factor = sin(SGMiscd::deg2rad(_elapsed_time * 10));
1177 double r_angle = 5 * factor;
1178 double p_angle = 2.5 * factor;
1179 double h_angle = 5 * factor;
1180 double h_feet = 3 * factor;
1182 pos.setLatitudeDeg(_offsetpos.getLatitudeDeg());
1183 pos.setLongitudeDeg(_offsetpos.getLongitudeDeg());
1185 if (getHtAGL(10000)){
1187 if(_ht_agl_ft <= 10) {
1188 _height = userpos.getElevationFt();
1189 } else if (_ht_agl_ft > 10 && _ht_agl_ft <= 150 ) {
1190 setHt(userpos.getElevationFt(), dt, 1.0);
1191 } else if (_ht_agl_ft > 150 && _ht_agl_ft <= 250) {
1192 setHt(_offsetpos.getElevationFt()+ h_feet, dt, 0.75);
1194 setHt(_offsetpos.getElevationFt()+ h_feet, dt, 0.5);
1196 pos.setElevationFt(_height);
1199 // these calculations are unreliable at slow speeds
1201 setHdg(_azimuth + h_angle, dt, 0.9);
1202 setPch(_elevation + p_angle + _pitch_offset, dt, 0.9);
1204 if (roll <= 115 && roll >= -115)
1205 setBnk(manager->get_user_roll() + r_angle + _roll_offset, dt, 0.5);
1207 roll = manager->get_user_roll() + r_angle + _roll_offset;
1210 setHdg(manager->get_user_heading(), dt, 0.9);
1211 setPch(manager->get_user_pitch() + _pitch_offset, dt, 0.9);
1212 setBnk(manager->get_user_roll() + _roll_offset, dt, 0.9);
1215 setOffsetVelocity(dt, pos);
1217 void FGAIBallistic::calcVSHS(){
1218 // calculate vertical and horizontal speed components
1219 double speed_fps = speed * SG_KT_TO_FPS;
1224 vs = sin( _elevation * SG_DEGREES_TO_RADIANS ) * speed_fps;
1225 hs = cos( _elevation * SG_DEGREES_TO_RADIANS ) * speed_fps;
1229 void FGAIBallistic::calcNE(){
1230 //resolve horizontal speed into north and east components:
1231 _speed_north_fps = cos(_azimuth / SG_RADIANS_TO_DEGREES) * hs;
1232 _speed_east_fps = sin(_azimuth / SG_RADIANS_TO_DEGREES) * hs;
1234 // convert horizontal speed (fps) to degrees per second
1235 speed_north_deg_sec = _speed_north_fps / ft_per_deg_lat;
1236 speed_east_deg_sec = _speed_east_fps / ft_per_deg_lon;
1240 SGVec3d FGAIBallistic::getCartOffsetPos(SGGeod inpos, double user_heading,
1241 double user_pitch, double user_roll
1244 // convert geodetic positions to geocentered
1245 SGVec3d cartuserPos = SGVec3d::fromGeod(inpos);
1246 //SGVec3d cartuserPos = getCartUserPos();
1247 //SGVec3d cartPos = getCartPos();
1249 // Transform to the right coordinate frame, configuration is done in
1250 // the x-forward, y-right, z-up coordinates (feet), computation
1251 // in the simulation usual body x-forward, y-right, z-down coordinates
1253 SGVec3d _off(_x_offset * SG_FEET_TO_METER,
1254 _y_offset * SG_FEET_TO_METER,
1255 -_z_offset * SG_FEET_TO_METER);
1257 // Transform the user position to the horizontal local coordinate system.
1258 SGQuatd hlTrans = SGQuatd::fromLonLat(userpos);
1260 // and postrotate the orientation of the user model wrt the horizontal
1262 hlTrans *= SGQuatd::fromYawPitchRollDeg(
1267 // The offset converted to the usual body fixed coordinate system
1268 // rotated to the earth-fixed coordinates axis
1269 SGVec3d off = hlTrans.backTransform(_off);
1271 // Add the position offset of the user model to get the geocentered position
1272 SGVec3d offsetPos = cartuserPos + off;
1277 void FGAIBallistic::setOffsetVelocity(double dt, SGGeod offsetpos) {
1278 //calculate the distance from the previous offset position
1279 SGVec3d cartoffsetPos = SGVec3d::fromGeod(offsetpos);
1280 SGVec3d diff = cartoffsetPos - _oldcartoffsetPos;
1282 double distance = norm(diff);
1283 //calculate speed knots
1284 speed = (distance/dt) * SG_MPS_TO_KT;
1286 //now calulate the angle between the old and current postion positions (degrees)
1288 double daltM = offsetpos.getElevationM() - _oldoffsetpos.getElevationM();
1290 if (fabs(distance) < SGLimits<float>::min()) {
1293 double sAngle = daltM/distance;
1294 sAngle = SGMiscd::min(1, SGMiscd::max(-1, sAngle));
1295 angle = SGMiscd::rad2deg(asin(sAngle));
1300 //calculate vertical and horizontal speed components
1303 //calculate the bearing of the new offset position from the old
1304 double az1, az2, dist;
1305 geo_inverse_wgs_84(_oldoffsetpos, offsetpos, &az1, &az2, &dist);
1308 //resolve horizontal speed into north and east components:
1311 // and finally store the new values
1312 _oldcartoffsetPos = cartoffsetPos;
1313 _oldoffsetpos = offsetpos;