FUNCTIONAL DESCRIPTION
--------------------------------------------------------------------------------
-This class takes the given set of IC's and finds the angle of attack, elevator,
-and throttle setting required to fly steady level. This is currently for in-air
-conditions only. It is implemented using an iterative, one-axis-at-a-time
-scheme.
+This class takes the given set of IC's and finds the aircraft state required to
+maintain a specified flight condition. This flight condition can be
+steady-level with non-zero sideslip, a steady turn, a pull-up or pushover.
+On-ground conditions can be trimmed as well, but this is currently limited to
+adjusting altitude and pitch angle only. It is implemented using an iterative,
+one-axis-at-a-time scheme.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
SENTRY
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
#include "FGFDMExec.h"
-#include "FGRotation.h"
-#include "FGAtmosphere.h"
-#include "FGState.h"
-#include "FGFCS.h"
-#include "FGAircraft.h"
-#include "FGTranslation.h"
-#include "FGPosition.h"
-#include "FGAuxiliary.h"
-#include "FGOutput.h"
-#include "FGTrim.h"
+#include "FGJSBBase.h"
#include "FGTrimAxis.h"
#include <vector>
#define ID_TRIM "$Id$"
+#if defined(_WIN32) && !defined(__CYGWIN__)
+ #define snprintf _snprintf
+#endif
+
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
FORWARD DECLARATIONS
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
-typedef enum { tLongitudinal, tFull, tGround, tCustom, tNone } TrimMode;
+namespace JSBSim {
-/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-COMMENTS, REFERENCES, and NOTES [use "class documentation" below for API docs]
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
+typedef enum { tLongitudinal, tFull, tGround, tPullup,
+ tCustom, tNone, tTurn
+ } TrimMode;
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
CLASS DOCUMENTATION
last three are used for on-ground trimming. The state-control pairs used in
a given trim are completely user configurable and several pre-defined modes
are provided as well. They are:
- <ul>
- <li> tLongitudinal: Trim wdot with alpha, udot with thrust, qdot with elevator</li>
- <li> tFull: tLongitudinal + vdot with phi, pdot with aileron, rdot with rudder
- and heading minus ground track (hmgt) with beta</li>
- <li> tGround: wdot with altitude, qdot with theta, and pdot with phi</li>
+ - tLongitudinal: Trim wdot with alpha, udot with thrust, qdot with elevator
+ - tFull: tLongitudinal + vdot with phi, pdot with aileron, rdot with rudder
+ and heading minus ground track (hmgt) with beta
+ - tPullup: tLongitudinal but adjust alpha to achieve load factor input
+ with SetTargetNlf()
+ - tGround: wdot with altitude, qdot with theta, and pdot with phi
+
The remaining modes include <b>tCustom</b>, which is completely user defined and
<b>tNone</b>.
- </ul>
- Currently, this class cannot trim a non-1g condition and is limited to
- trimming for constant true airspeed in climbs and descents.
-
+
Note that trims can (and do) fail for reasons that are completely outside
the control of the trimming routine itself. The most common problem is the
initial conditions: is the model capable of steady state flight
at those conditions? Check the speed, altitude, configuration (flaps,
gear, etc.), weight, cg, and anything else that may be relevant.
- Example usage:
+ Example usage:<pre>
FGFDMExec* FDMExec = new FGFDMExec();
- .
- .
- .
+
FGInitialCondition* fgic = new FGInitialCondition(FDMExec);
FGTrim *fgt(FDMExec,fgic,tFull);
fgic->SetVcaibratedKtsIC(100);
if( !fgt->DoTrim() ) {
cout << "Trim Failed" << endl;
}
- fgt->ReportState();
+ fgt->ReportState(); </pre>
@author Tony Peden
- @version $Id$
+ @version "$Id$"
*/
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
CLASS DECLARATION
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
-class FGTrim {
+class FGTrim : public FGJSBBase
+{
private:
vector<FGTrimAxis*> TrimAxes;
- int current_axis;
+ unsigned int current_axis;
int N, Nsub;
TrimMode mode;
- int Debug;
- float Tolerance, A_Tolerance;
- float wdot,udot,qdot;
- float dth;
- float *sub_iterations;
- float *successful;
+ int DebugLevel, Debug;
+ double Tolerance, A_Tolerance;
+ double wdot,udot,qdot;
+ double dth;
+ double *sub_iterations;
+ double *successful;
bool *solution;
int max_sub_iterations;
int max_iterations;
bool trimudot;
bool gamma_fallback;
bool trim_failed;
- int axis_count;
+ unsigned int axis_count;
int solutionDomain;
- float xlo,xhi,alo,ahi;
+ double xlo,xhi,alo,ahi;
+ double targetNlf;
+ int debug_axis;
+
+ double psidot,thetadot;
FGFDMExec* fdmex;
FGInitialCondition* fgic;
- bool solve(void);
+ bool solve(void);
/** @return false if there is no change in the current axis accel
between accel(control_min) and accel(control_max). If there is a
bool findInterval(void);
bool checkLimits(void);
+
+ void setupPullup(void);
+ void setupTurn(void);
+
+ void updateRates(void);
+
+ void setDebug(void);
public:
/** Initializes the trimming class
@param FDMExec pointer to a JSBSim executive object.
- @param FGIC pointer to a FGInitialCondition object
- @param TrimMode the set of axes to trim. Can be:
- tLongitudinal, tFull, tGround, tCustom, or tNone
+ @param tm trim mode
*/
- FGTrim(FGFDMExec *FDMExec, FGInitialCondition *FGIC, TrimMode tt);
+ FGTrim(FGFDMExec *FDMExec, TrimMode tm=tGround );
- ~FGTrim(void);
+ ~FGTrim(void);
/** Execute the trim
*/
*/
void Report(void);
- /** Prints a summary of simulator state (speed, altitude,
- configuration, etc.)
- */
- void ReportState(void);
-
/** Iteration statistics
*/
void TrimStats();
+
+ /** Clear all state-control pairs and set a predefined trim mode
+ @param tm the set of axes to trim. Can be:
+ tLongitudinal, tFull, tGround, tCustom, or tNone
+ */
+ void SetMode(TrimMode tm);
/** Clear all state-control pairs from the current configuration.
The trimming routine must have at least one state-control pair
/** Change the control used to zero a state previously configured
@param state the accel or other condition to zero
- @param control the control used to zero the state
+ @param new_control the control used to zero the state
*/
bool EditState( State state, Control new_control );
/** automatically switch to trimming longitudinal acceleration with
flight path angle (gamma) once it becomes apparent that there
is not enough/too much thrust.
- @param gamma_fallback true to enable fallback
+ @param bb true to enable fallback
*/
- inline void SetGammaFallback(bool bb) { gamma_fallback=true; }
+ inline void SetGammaFallback(bool bb) { gamma_fallback=bb; }
/** query the fallback state
@return true if fallback is enabled.
held to a tolerance of 1/10th of the given. The default is
0.001 for the recti-linear accelerations and 0.0001 for the angular.
*/
- inline void SetTolerance(float tt) {
+ inline void SetTolerance(double tt) {
Tolerance = tt;
A_Tolerance = tt / 10;
}
- //Debug level 1 shows results of each top-level iteration
- //Debug level 2 shows level 1 & results of each per-axis iteration
- inline void SetDebug(int level) { Debug = level; }
- inline void ClearDebug(void) { Debug = 0; }
+ /**
+ Debug level 1 shows results of each top-level iteration
+ Debug level 2 shows level 1 & results of each per-axis iteration
+ */
+ inline void SetDebug(int level) { DebugLevel = level; }
+ inline void ClearDebug(void) { DebugLevel = 0; }
+
+ /**
+ Output debug data for one of the axes
+ The State enum is defined in FGTrimAxis.h
+ */
+ inline void DebugState(State state) { debug_axis=state; }
+
+ inline void SetTargetNlf(float nlf) { targetNlf=nlf; }
+ inline double GetTargetNlf(void) { return targetNlf; }
};
-
+}
#endif
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