src/FDM/JSBSim/models/flight_control/FGSensor.h

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Header:       FGSensor.h
   4  Author:       Jon Berndt
   5  Date started: 9 July 2005
   6
   7  ------------- Copyright (C) 2005 -------------
   8
   9  This program is free software; you can redistribute it and/or modify it under
  10  the terms of the GNU General Public License as published by the Free Software
  11  Foundation; either version 2 of the License, or (at your option) any later
  12  version.
  13
  14  This program is distributed in the hope that it will be useful, but WITHOUT
  15  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  16  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  17  details.
  18
  19  You should have received a copy of the GNU General Public License along with
  20  this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  21  Place - Suite 330, Boston, MA  02111-1307, USA.
  22
  23  Further information about the GNU General Public License can also be found on
  24  the world wide web at http://www.gnu.org.
  25
  26 HISTORY
  27 --------------------------------------------------------------------------------
  28
  29 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  30 SENTRY
  31 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  32
  33 #ifndef FGSENSOR_H
  34 #define FGSENSOR_H
  35
  36 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  37 INCLUDES
  38 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  39
  40 #include "FGFCSComponent.h"
  41 #include <input_output/FGXMLElement.h>
  42
  43 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  44 DEFINITIONS
  45 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  46
  47 #define ID_SENSOR "$Id$"
  48
  49 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  50 FORWARD DECLARATIONS
  51 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  52
  53 namespace JSBSim {
  54
  55 class FGFCS;
  56
  57 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  58 CLASS DOCUMENTATION
  59 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  60
  61 /** Encapsulates a Sensor component for the flight control system.
  62
  63 Syntax:
  64
  65 <sensor name=\94name\94 rate_group=\94name\94>
  66   <input> property </input>
  67   <lag> number </lag>
  68   <noise variation=\94PERCENT|ABSOLUTE\94> number </noise>
  69   <quantization name="name">
  70     <bits> number </bits>
  71     <min> number </min>
  72     <max> number </max>
  73   </quantization>
  74   <drift_rate> number </drift_rate>
  75   <bias> number </bias>
  76 </sensor>
  77
  78 Example:
  79
  80 <sensor name=\94aero/sensor/qbar\94 rate_group=\94HFCS\94>
  81   <input> aero/qbar </input>
  82   <lag> 0.5 </lag>
  83   <noise variation=\94PERCENT\94> 2 </noise>
  84   <quantization name="aero/sensor/quantized/qbar">
  85     <bits> 12 </bits>
  86     <min> 0 </min>
  87     <max> 400 </max>
  88   </quantization>
  89   <bias> 0.5 </bias>
  90 </sensor>
  91
  92 The only required element in the sensor definition is the input element. In that
  93 case, no degradation would be modeled, and the output would simply be the input.
  94
  95 For noise, if the type is PERCENT, then the value supplied is understood to be a
  96 percentage variance. That is, if the number given is 0.05, the the variance is
  97 understood to be +/-0.05 percent maximum variance. So, the actual value for the sensor
  98 will be *anywhere* from 0.95 to 1.05 of the actual "perfect" value at any time -
  99 even varying all the way from 0.95 to 1.05 in adjacent frames - whatever the delta
 100 time.
 101
 102   */
 103
 104 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 105 CLASS DECLARATION
 106 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 107
 108 class FGSensor  : public FGFCSComponent
 109 {
 110 public:
 111   FGSensor(FGFCS* fcs, Element* element);
 112   ~FGSensor();
 113
 114   inline void SetFailLow(double val) {if (val > 0.0) fail_low = true; else fail_low = false;}
 115   inline void SetFailHigh(double val) {if (val > 0.0) fail_high = true; else fail_high = false;}
 116   inline void SetFailStuck(double val) {if (val > 0.0) fail_stuck = true; else fail_stuck = false;}
 117
 118   inline double GetFailLow(void) const {if (fail_low) return 1.0; else return 0.0;}
 119   inline double GetFailHigh(void) const {if (fail_high) return 1.0; else return 0.0;}
 120   inline double GetFailStuck(void) const {if (fail_stuck) return 1.0; else return 0.0;}
 121
 122   bool Run (void);
 123
 124 private:
 125   enum eNoiseType {ePercent=0, eAbsolute} NoiseType;
 126   double dt;
 127   double min, max;
 128   double span;
 129   double bias;
 130   double drift_rate;
 131   double drift;
 132   double noise_variance;
 133   double lag;
 134   double granularity;
 135   double ca; /// lag filter coefficient "a"
 136   double cb; /// lag filter coefficient "b"
 137   double PreviousOutput;
 138   double PreviousInput;
 139   int noise_type;
 140   int bits;
 141   int quantized;
 142   int divisions;
 143   bool fail_low;
 144   bool fail_high;
 145   bool fail_stuck;
 146
 147   void Noise(void);
 148   void Bias(void);
 149   void Drift(void);
 150   void Quantize(void);
 151   void Lag(void);
 152
 153   void bind(void);
 154
 155   void Debug(int from);
 156 };
 157 }
 158 #endif