From c92cb650eb9b10c22c59078a177816d431301dd7 Mon Sep 17 00:00:00 2001 From: ehofman Date: Sat, 14 Feb 2004 10:19:56 +0000 Subject: [PATCH] Add the latest version of JSBSim including support for a Visual Reference Point --- src/FDM/JSBSim/FGAerodynamics.cpp | 7 +- src/FDM/JSBSim/FGAuxiliary.cpp | 12 ++-- src/FDM/JSBSim/FGFCS.cpp | 1 - src/FDM/JSBSim/FGForce.cpp | 4 +- src/FDM/JSBSim/FGJSBBase.cpp | 4 +- src/FDM/JSBSim/FGJSBBase.h | 2 +- src/FDM/JSBSim/FGLGear.cpp | 15 +---- src/FDM/JSBSim/FGMassBalance.cpp | 33 ++++++++++ src/FDM/JSBSim/FGMassBalance.h | 8 +++ src/FDM/JSBSim/FGMatrix33.h | 1 - src/FDM/JSBSim/FGPosition.cpp | 15 ++--- src/FDM/JSBSim/FGSimTurbine.cpp | 1 + src/FDM/JSBSim/FGState.h | 2 +- src/FDM/JSBSim/JSBSim.cxx | 5 +- src/FDM/JSBSim/JSBSim.hxx | 8 --- src/FDM/JSBSim/filtersjb/FGDeadBand.h | 29 +++++---- src/FDM/JSBSim/filtersjb/FGFilter.cpp | 12 ++-- src/FDM/JSBSim/filtersjb/FGFilter.h | 15 +++-- src/FDM/JSBSim/filtersjb/FGGain.h | 93 ++++++++++++++++++++++++++- src/FDM/JSBSim/filtersjb/FGSummer.h | 28 +++++++- src/FDM/JSBSim/filtersjb/FGSwitch.h | 32 +++++++-- 21 files changed, 238 insertions(+), 89 deletions(-) diff --git a/src/FDM/JSBSim/FGAerodynamics.cpp b/src/FDM/JSBSim/FGAerodynamics.cpp index 43d59bb07..7617c1f2f 100644 --- a/src/FDM/JSBSim/FGAerodynamics.cpp +++ b/src/FDM/JSBSim/FGAerodynamics.cpp @@ -157,12 +157,7 @@ bool FGAerodynamics::Run(void) vForces = State->GetTs2b()*vFs; - vDXYZcg(eX) = -(Aircraft->GetXYZrp(eX) - - MassBalance->GetXYZcg(eX))*inchtoft; - vDXYZcg(eY) = (Aircraft->GetXYZrp(eY) - - MassBalance->GetXYZcg(eY))*inchtoft; - vDXYZcg(eZ) = -(Aircraft->GetXYZrp(eZ) - - MassBalance->GetXYZcg(eZ))*inchtoft; + vDXYZcg = MassBalance->StructuralToBody(Aircraft->GetXYZrp()); vMoments = vDXYZcg*vForces; // M = r X F diff --git a/src/FDM/JSBSim/FGAuxiliary.cpp b/src/FDM/JSBSim/FGAuxiliary.cpp index a630eab38..ca86c769e 100644 --- a/src/FDM/JSBSim/FGAuxiliary.cpp +++ b/src/FDM/JSBSim/FGAuxiliary.cpp @@ -103,7 +103,7 @@ bool FGAuxiliary::Run() tatc=RankineToCelsius(tat); if (mach < 1) { //calculate total pressure assuming isentropic flow - pt=p*pow((1 + 0.2*machU*machU),3.5); + pt = p*pow((1 + 0.2*machU*machU),3.5); } else { // shock in front of pitot tube, we'll assume its normal and use // the Rayleigh Pitot Tube Formula, i.e. the ratio of total @@ -167,11 +167,10 @@ bool FGAuxiliary::Run() vPilotAccel.InitMatrix(); if ( Translation->GetVt() > 1 ) { vPilotAccel = Aerodynamics->GetForces() - + Propulsion->GetForces() - + GroundReactions->GetForces(); + + Propulsion->GetForces() + + GroundReactions->GetForces(); vPilotAccel /= MassBalance->GetMass(); - vToEyePt = Aircraft->GetXYZep() - MassBalance->GetXYZcg(); - vToEyePt *= inchtoft; + vToEyePt = MassBalance->StructuralToBody(Aircraft->GetXYZep()); vPilotAccel += Rotation->GetPQRdot() * vToEyePt; vPilotAccel += Rotation->GetPQR() * (Rotation->GetPQR() * vToEyePt); } else { @@ -179,8 +178,7 @@ bool FGAuxiliary::Run() } vPilotAccelN = vPilotAccel/Inertial->gravity(); - - + earthPosAngle += State->Getdt()*Inertial->omega(); return false; } else { diff --git a/src/FDM/JSBSim/FGFCS.cpp b/src/FDM/JSBSim/FGFCS.cpp index 5aaf4e306..bf7778d4d 100644 --- a/src/FDM/JSBSim/FGFCS.cpp +++ b/src/FDM/JSBSim/FGFCS.cpp @@ -111,7 +111,6 @@ FGFCS::~FGFCS() PropAdvanceCmd.clear(); PropAdvance.clear(); - unsigned int i; for (i=0;iGetMassBalance()->GetXYZcg(eX))*inchtoft; - vDXYZ(eY) = (vActingXYZn(eY) - fdmex->GetMassBalance()->GetXYZcg(eY))*inchtoft; - vDXYZ(eZ) = -(vActingXYZn(eZ) - fdmex->GetMassBalance()->GetXYZcg(eZ))*inchtoft; + vDXYZ = fdmex->GetMassBalance()->StructuralToBody(vActingXYZn); vM = vMn + vDXYZ*vFb; diff --git a/src/FDM/JSBSim/FGJSBBase.cpp b/src/FDM/JSBSim/FGJSBBase.cpp index f191791a5..3c5b6f867 100644 --- a/src/FDM/JSBSim/FGJSBBase.cpp +++ b/src/FDM/JSBSim/FGJSBBase.cpp @@ -66,9 +66,9 @@ const double FGJSBBase::fpstokts = 0.592484; const double FGJSBBase::ktstofps = 1.68781; const double FGJSBBase::inchtoft = 0.08333333; const double FGJSBBase::in3tom3 = 1.638706E-5; -const double FGJSBBase::Reng = 1716.0; +double FGJSBBase::Reng = 1716.0; const double FGJSBBase::SHRatio = 1.40; -const string FGJSBBase::needed_cfg_version = "1.60"; +const string FGJSBBase::needed_cfg_version = "1.61"; const string FGJSBBase::JSBSim_version = "0.9.5"; std::queue FGJSBBase::Messages; diff --git a/src/FDM/JSBSim/FGJSBBase.h b/src/FDM/JSBSim/FGJSBBase.h index 8ca173d2b..9f05b313f 100644 --- a/src/FDM/JSBSim/FGJSBBase.h +++ b/src/FDM/JSBSim/FGJSBBase.h @@ -238,7 +238,7 @@ protected: static const double ktstofps; static const double inchtoft; static const double in3tom3; - static const double Reng; // Specific Gas Constant,ft^2/(sec^2*R) + static double Reng; // Specific Gas Constant,ft^2/(sec^2*R) static const double SHRatio; static const string needed_cfg_version; static const string JSBSim_version; diff --git a/src/FDM/JSBSim/FGLGear.cpp b/src/FDM/JSBSim/FGLGear.cpp index bdbd56f03..4bdb1f2fe 100644 --- a/src/FDM/JSBSim/FGLGear.cpp +++ b/src/FDM/JSBSim/FGLGear.cpp @@ -115,9 +115,7 @@ FGLGear::FGLGear(FGConfigFile* AC_cfg, FGFDMExec* fdmex) : Exec(fdmex) MaximumStrutForce = MaximumStrutTravel = 0.0; SinkRate = GroundSpeed = 0.0; - vWhlBodyVec = (vXYZ - MassBalance->GetXYZcg()) / 12.0; - vWhlBodyVec(eX) = -vWhlBodyVec(eX); - vWhlBodyVec(eZ) = -vWhlBodyVec(eZ); + vWhlBodyVec = MassBalance->StructuralToBody(vXYZ); vLocalGear = State->GetTb2l() * vWhlBodyVec; @@ -233,9 +231,7 @@ FGColumnVector3& FGLGear::Force(void) if (GearDown) { - vWhlBodyVec = (vXYZ - MassBalance->GetXYZcg()) / 12.0; - vWhlBodyVec(eX) = -vWhlBodyVec(eX); - vWhlBodyVec(eZ) = -vWhlBodyVec(eZ); + vWhlBodyVec = MassBalance->StructuralToBody(vXYZ); // vWhlBodyVec now stores the vector from the cg to this wheel @@ -403,13 +399,6 @@ FGColumnVector3& FGLGear::Force(void) FCoeff = dynamicFCoeff*fabs(WheelSlip)/WheelSlip; } -#if 0 - // A negative force coefficient will result in a force pulling the wheel(s) - // back instead of trying to stop them from moving. - if (FCoeff < 0.0) - FCoeff = 0.0; -#endif - // Compute the vertical force on the wheel using square-law damping (per comment // in paper AIAA-2000-4303 - see header prologue comments). We might consider // allowing for both square and linear damping force calculation. Also need to diff --git a/src/FDM/JSBSim/FGMassBalance.cpp b/src/FDM/JSBSim/FGMassBalance.cpp index ab9b725d4..582f1d957 100644 --- a/src/FDM/JSBSim/FGMassBalance.cpp +++ b/src/FDM/JSBSim/FGMassBalance.cpp @@ -198,6 +198,39 @@ double FGMassBalance::GetPMIxz(void) //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +FGColumnVector3 FGMassBalance::StructuralToBody(const FGColumnVector3& r) const +{ + // Under the assumption that in the structural frame the: + // + // - X-axis is directed afterwards, + // - Y-axis is directed towards the right, + // - Z-axis is directed upwards, + // + // (as documented in http://jsbsim.sourceforge.net/JSBSimCoordinates.pdf) + // we have to subtract first the center of gravity of the plane which + // is also defined in the structural frame: + // + // FGColumnVector3 cgOff = r - vXYZcg; + // + // Next, we do a change of units: + // + // cgOff *= inchtoft; + // + // And then a 180 degree rotation is done about the Y axis so that the: + // + // - X-axis is directed forward, + // - Y-axis is directed towards the right, + // - Z-axis is directed downward. + // + // This is needed because the structural and body frames are 180 degrees apart. + + return FGColumnVector3(inchtoft*(vXYZcg(1)-r(1)), + inchtoft*(r(2)-vXYZcg(2)), + inchtoft*(vXYZcg(3)-r(3))); +} + +//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + void FGMassBalance::bind(void) { typedef double (FGMassBalance::*PMF)(int) const; diff --git a/src/FDM/JSBSim/FGMassBalance.h b/src/FDM/JSBSim/FGMassBalance.h index a81d7c665..c53288219 100644 --- a/src/FDM/JSBSim/FGMassBalance.h +++ b/src/FDM/JSBSim/FGMassBalance.h @@ -84,6 +84,14 @@ public: inline FGColumnVector3& GetXYZcg(void) {return vXYZcg;} inline double GetXYZcg(int axis) const {return vXYZcg(axis);} + /** Conversion from the structural frame to the body frame. + * Converts the argument \parm r given in the reference frame + * coordinate system to the body frame. The units of the structural + * frame are assumed to be in inches. The unit of the result is in + * ft. + */ + FGColumnVector3 StructuralToBody(const FGColumnVector3& r) const; + inline void SetEmptyWeight(double EW) { EmptyWeight = EW;} inline void SetBaseIxx(double bixx) { baseIxx = bixx;} inline void SetBaseIyy(double biyy) { baseIyy = biyy;} diff --git a/src/FDM/JSBSim/FGMatrix33.h b/src/FDM/JSBSim/FGMatrix33.h index 6a04049b2..bbf168be1 100644 --- a/src/FDM/JSBSim/FGMatrix33.h +++ b/src/FDM/JSBSim/FGMatrix33.h @@ -47,7 +47,6 @@ INCLUDES # else # include # endif -# include using std::ostream; using std::istream; using std::cerr; diff --git a/src/FDM/JSBSim/FGPosition.cpp b/src/FDM/JSBSim/FGPosition.cpp index a003cc189..932c511b2 100644 --- a/src/FDM/JSBSim/FGPosition.cpp +++ b/src/FDM/JSBSim/FGPosition.cpp @@ -184,8 +184,7 @@ bool FGPosition::Run(void) h = Radius - SeaLevelRadius; // Geocentric - vVRPoffset = State->GetTb2l() * (vVRP - MassBalance->GetXYZcg()); - vVRPoffset /= 12.0; // converted to feet + vVRPoffset = State->GetTb2l() * MassBalance->StructuralToBody(Aircraft->GetXYZvrp()); // vVRP - the vector to the Visual Reference Point - now contains the // offset from the CG to the VRP, in units of feet, in the Local coordinate @@ -196,19 +195,17 @@ bool FGPosition::Run(void) LongitudeVRP = vVRPoffset(eEast) / (Radius * cosLat) + Longitude; LatitudeVRP = vVRPoffset(eNorth) / Radius + Latitude; - hVRP = vVRPoffset(eDown) + h; + hVRP = h - vVRPoffset(eDown); /* cout << "Lat/Lon/Alt : " << Latitude << " / " << Longitude << " / " << h << endl; cout << "Lat/Lon/Alt VRP: " << LatitudeVRP << " / " << LongitudeVRP << " / " << hVRP << endl << endl; */ DistanceAGL = Radius - RunwayRadius; // Geocentric - + hoverbcg = DistanceAGL/b; - - vMac = State->GetTb2l()*Aircraft->GetXYZrp(); - - vMac *= inchtoft; - hoverbmac = (DistanceAGL + vMac(3))/b; + + vMac = State->GetTb2l()*MassBalance->StructuralToBody(Aircraft->GetXYZrp()); + hoverbmac = (DistanceAGL + vMac(3)) / b; if (Vt > 0) { hdot_Vt = RadiusDot/Vt; diff --git a/src/FDM/JSBSim/FGSimTurbine.cpp b/src/FDM/JSBSim/FGSimTurbine.cpp index 3558297d4..36ff0d4b3 100644 --- a/src/FDM/JSBSim/FGSimTurbine.cpp +++ b/src/FDM/JSBSim/FGSimTurbine.cpp @@ -131,6 +131,7 @@ double FGSimTurbine::Off(void) OilPressure_psi = N2 * 0.62; NozzlePosition = Seek(&NozzlePosition, 1.0, 0.8, 0.8); EPR = Seek(&EPR, 1.0, 0.2, 0.2); + Augmentation = false; return 0.0; } diff --git a/src/FDM/JSBSim/FGState.h b/src/FDM/JSBSim/FGState.h index 0995d8e0d..bb8875c3c 100644 --- a/src/FDM/JSBSim/FGState.h +++ b/src/FDM/JSBSim/FGState.h @@ -49,7 +49,7 @@ INCLUDES # include # endif #else -# if defined(sgi) && !defined(__GNUC__) +# if defined(sgi) && !defined(__GNUC__) && (_COMPILER_VERSION < 740) # include # else # include diff --git a/src/FDM/JSBSim/JSBSim.cxx b/src/FDM/JSBSim/JSBSim.cxx index 283e783a5..573b6d495 100644 --- a/src/FDM/JSBSim/JSBSim.cxx +++ b/src/FDM/JSBSim/JSBSim.cxx @@ -105,7 +105,7 @@ FGJSBsim::FGJSBsim( double dt ) } fdmex = new FGFDMExec( (FGPropertyManager*)globals->get_props() ); - + State = fdmex->GetState(); Atmosphere = fdmex->GetAtmosphere(); FCS = fdmex->GetFCS(); @@ -156,8 +156,7 @@ FGJSBsim::FGJSBsim( double dt ) SG_LOG( SG_FLIGHT, SG_ALERT, "Halting the sim now, and hoping a solution will present itself soon!"); exit(-1); } - - + init_gear(); // Set initial fuel levels if provided. diff --git a/src/FDM/JSBSim/JSBSim.hxx b/src/FDM/JSBSim/JSBSim.hxx index a27512169..3e11f54ab 100644 --- a/src/FDM/JSBSim/JSBSim.hxx +++ b/src/FDM/JSBSim/JSBSim.hxx @@ -76,10 +76,6 @@ class FGInitialCondition; using namespace JSBSim; -/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -COMMENTS, REFERENCES, and NOTES [use "class documentation" below for API docs] -%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/ - /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% CLASS DOCUMENTATION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/ @@ -93,10 +89,6 @@ CLASS DOCUMENTATION @author Tony Peden (Maintained and refined) @version $Id$ @see main in file JSBSim.cpp (use main() wrapper for standalone usage) - @see - Header File - @see - Source File */ /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% diff --git a/src/FDM/JSBSim/filtersjb/FGDeadBand.h b/src/FDM/JSBSim/filtersjb/FGDeadBand.h index dab0d9351..af385ffc3 100644 --- a/src/FDM/JSBSim/filtersjb/FGDeadBand.h +++ b/src/FDM/JSBSim/filtersjb/FGDeadBand.h @@ -59,20 +59,23 @@ CLASS DOCUMENTATION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/ /** Models a deadband object. - Owned and Operated by the FGFCS class. - - - INPUT {input} - WIDTH {deadband width} - GAIN {optional deadband gain} - MIN {minimum value} - MAX {maximum value} - OUTPUT {optional output parameter to set} - - + Here is the format of the deadband control specification: + 
+    \
+       INPUT {input}
+       WIDTH {deadband width}
+       MIN {minimum value}
+       MAX {maximum value}
+       [GAIN {optional deadband gain}]
+       [OUTPUT {optional output parameter to set}]
+    \
+
+ The WIDTH value is the total deadband region within which an input will + produce no output. For example, say that the WIDTH value is 2.0. If the + input is between -1.0 and +1.0, the output will be zero. @author Jon S. Berndt - @see - - */ + @version $Id$ +*/ /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% CLASS DECLARATION diff --git a/src/FDM/JSBSim/filtersjb/FGFilter.cpp b/src/FDM/JSBSim/filtersjb/FGFilter.cpp index 6fa065b84..c8ba414e8 100644 --- a/src/FDM/JSBSim/filtersjb/FGFilter.cpp +++ b/src/FDM/JSBSim/filtersjb/FGFilter.cpp @@ -118,12 +118,12 @@ FGFilter::FGFilter(FGFCS* fcs, FGConfigFile* AC_cfg) : FGFCSComponent(fcs), cc = (2.00*C3 - dt*C2) / denom; break; case eOrder2: - denom = 4.0*C3 + 2.0*C5*dt + C6*dt*dt; - ca = 4.0*C1 + 2.0*C2*dt + C3*dt*dt / denom; - cb = 2.0*C3*dt*dt - 8.0*C1 / denom; - cc = 4.0*C1 - 2.0*C2*dt + C3*dt*dt / denom; - cd = 2.0*C6*dt*dt - 8.0*C4 / denom; - ce = 4.0*C3 - 2.0*C5*dt + C6*dt*dt / denom; + denom = 4.0*C4 + 2.0*C5*dt + C6*dt*dt; + ca = (4.0*C1 + 2.0*C2*dt + C3*dt*dt) / denom; + cb = (2.0*C3*dt*dt - 8.0*C1) / denom; + cc = (4.0*C1 - 2.0*C2*dt + C3*dt*dt) / denom; + cd = (2.0*C6*dt*dt - 8.0*C4) / denom; + ce = (4.0*C4 - 2.0*C5*dt + C6*dt*dt) / denom; break; case eWashout: denom = 2.00 + dt*C1; diff --git a/src/FDM/JSBSim/filtersjb/FGFilter.h b/src/FDM/JSBSim/filtersjb/FGFilter.h index 49ef57726..521e2d888 100644 --- a/src/FDM/JSBSim/filtersjb/FGFilter.h +++ b/src/FDM/JSBSim/filtersjb/FGFilter.h @@ -166,14 +166,19 @@ The corresponding filter definition is: [TRIGGER \] \ -For the integrator, the TRIGGER features the following behavior, if the TRIGGER property value is: +For the integrator, the TRIGGER features the following behavior, if the TRIGGER +property value is: - -1 (or simply less than zero), all previous inputs and outputs are set to 0.0 - 0, no action is taken - the output is calculated normally - +1 (or simply greater than zero), all previous outputs (only) will be set to 0.0 - - @author Jon S. Berndt - @version $Id$ - */ + +In all the filter specifications above, an [OUTPUT] keyword is also seen. This +is so that the last component in a "string" can copy its value to the appropriate +output, such as the elevator, or speedbrake, etc. + +@author Jon S. Berndt +@version $Id$ +*/ /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% CLASS DECLARATION diff --git a/src/FDM/JSBSim/filtersjb/FGGain.h b/src/FDM/JSBSim/filtersjb/FGGain.h index d76269867..7031d7efd 100644 --- a/src/FDM/JSBSim/filtersjb/FGGain.h +++ b/src/FDM/JSBSim/filtersjb/FGGain.h @@ -68,7 +68,98 @@ CLASS DOCUMENTATION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/ /** Encapsulates a gain component for the flight control system. - */ + The gain component merely multiplies the input by a gain. The form of the + gain component specification is: + 
+    \
+      INPUT \
+      GAIN  \
+      [OUTPUT \]
+    \
+
+ Note: as is the case with the Summer component, the input property name may be + immediately preceded by a minus sign to invert that signal. + + The scheduled gain component multiplies the input by a variable gain that is + dependent on another property (such as qbar, altitude, etc.). The lookup + mapping is in the form of a table. This kind of component might be used, for + example, in a case where aerosurface deflection must only be commanded to + acceptable settings - i.e at higher qbar the commanded elevator setting might + be attenuated. The form of the scheduled gain component specification is: + 
+    \
+      INPUT \
+      [GAIN  \]
+      SCHEDULED_BY \
+      ROWS \
+      \
+      ?
+      [OUTPUT \]
+    \
+
+ An overall GAIN may be supplied that is multiplicative with the scheduled gain. + + Note: as is the case with the Summer component, the input property name may + be immediately preceded by a minus sign to invert that signal. + + Here is an example of a scheduled gain component specification: + 
+    \
+      INPUT        fcs/pitch-gain-1
+      GAIN         0.017
+      SCHEDULED_BY fcs/elevator-pos-rad
+      ROWS         22
+      -0.68  -26.548
+      -0.595 -20.513
+      -0.51  -15.328
+      -0.425 -10.993
+      -0.34   -7.508
+      -0.255  -4.873
+      -0.17   -3.088
+      -0.085  -2.153
+       0      -2.068
+       0.085  -2.833
+       0.102  -3.088
+       0.119  -3.377
+       0.136  -3.7
+       0.153  -4.057
+       0.17   -4.448
+       0.187  -4.873
+       0.272  -7.508
+       0.357 -10.993
+       0.442 -15.328
+       0.527 -20.513
+       0.612 -26.548
+       0.697 -33.433
+    \
+
+ In the example above, we see the utility of the overall GAIN value in + effecting a degrees-to-radians conversion. + + The aerosurface scale component is a modified version of the simple gain + component. The normal purpose + for this component is to take control inputs that range from -1 to +1 or + from 0 to +1 and scale them to match the expected inputs to a flight control + system. For instance, the normal and expected ability of a pilot to push or + pull on a control stick is about 50 pounds. The input to the pitch channelb + lock diagram of a flight control system is in units of pounds. Yet, the + joystick control input is usually in a range from -1 to +1. The form of the + aerosurface scaling component specification is: +
+    \
+      INPUT \
+      MIN \
+      MAX \
+      [GAIN  \]
+      [OUTPUT \]
+    \
+
+ Note: as is the case with the Summer component, the input property name may be + immediately preceded by a minus sign to invert that signal. + + @author Jon S. Berndt + @version $Id$ +*/ /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% CLASS DECLARATION diff --git a/src/FDM/JSBSim/filtersjb/FGSummer.h b/src/FDM/JSBSim/filtersjb/FGSummer.h index 172dc8b5e..6bb7cae18 100644 --- a/src/FDM/JSBSim/filtersjb/FGSummer.h +++ b/src/FDM/JSBSim/filtersjb/FGSummer.h @@ -69,8 +69,32 @@ CLASS DOCUMENTATION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/ /** Models a flight control system summing component. - The Summer component sums multiple inputs. These can be pilot control inputs, - state variables, or even floating point numbers (e.g. for a bias). + The Summer component sums two or more inputs. These can be pilot control + inputs or state variables, and a bias can also be added in using the BIAS + keyword. The form of the summer component specification is: +
+    \
+      INPUT \
+      INPUT \
+      [BIAS \]
+      [?]
+      [CLIPTO \ \ 1]
+      [OUTPUT \]
+    \
+
+ Note that in the case of an input property the property name may be + immediately preceded by a minus sign. Here's an example of a summer + component specification: +
+    \
+      INPUT  velocities/p-rad_sec
+      INPUT -fcs/roll-ap-wing-leveler
+      INPUT  fcs/roll-ap-error-integrator
+      CLIPTO -1 1
+    \
+
+ Note that there can be only one BIAS statement per component. + @author Jon S. Berndt @version $Id$ */ diff --git a/src/FDM/JSBSim/filtersjb/FGSwitch.h b/src/FDM/JSBSim/filtersjb/FGSwitch.h index 3220a268c..451bbb223 100644 --- a/src/FDM/JSBSim/filtersjb/FGSwitch.h +++ b/src/FDM/JSBSim/filtersjb/FGSwitch.h @@ -62,13 +62,13 @@ CLASS DOCUMENTATION The SWITCH component models a switch - either on/off or a multi-choice rotary switch. The switch can represent a physical cockpit switch, or can represent a logical switch, where several conditions might need to be satisfied before a -particular state is reached. The VALUE of the switch - the output value - is -chosen depending on the state of the switch. Each switch is comprised of two or -more TESTs. Each TEST has a VALUE associated with it. The first TEST that -evaluates to TRUE will set the output value of the switch according to the VALUE -parameter belonging to that TEST. Each TEST contains one or more CONDITIONS, which -each must be logically related (if there are more than one) given the value of -the LOGIC parameter, and which takes the form: +particular state is reached. The VALUE of the switch - the output value for the +component - is chosen depending on the state of the switch. Each switch is +comprised of two or more TESTs. Each TEST has a VALUE associated with it. The +first TEST that evaluates to TRUE will set the output value of the switch +according to the VALUE parameter belonging to that TEST. Each TEST contains one +or more CONDITIONS, which each must be logically related (if there are more than +one) given the value of the LOGIC parameter, and which takes the form: property conditional property|value @@ -101,6 +101,24 @@ additional conditions, as well as possibly additional CONDITION_GROUPs. ... \ + +Here's an example: +
+\
+  \
+  \
+  \
+    ap/attitude_hold == 1
+  \
+\
+
+The above example specifies that the default value of the component (i.e. the +output property of the component, addressed by the property, ap/roll-ap-autoswitch) +is 0.0. If or when the attitude hold switch is selected (property +ap/attitude_hold takes the value 1), the value of the switch component will be +whatever value fcs/roll-ap-error-summer is. +@author Jon S. Berndt +@version $Id$ */ /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%