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 Lesser 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 Lesser General Public License for more
  17  details.
  18
  19  You should have received a copy of the GNU Lesser 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 Lesser 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 @code
  66 <sensor name=\94name\94 rate_group=\94name\94>
  67   <input> property </input>
  68   <lag> number </lag>
  69   <noise variation=\94PERCENT|ABSOLUTE\94> number </noise>
  70   <quantization name="name">
  71     <bits> number </bits>
  72     <min> number </min>
  73     <max> number </max>
  74   </quantization>
  75   <drift_rate> number </drift_rate>
  76   <bias> number </bias>
  77 </sensor>
  78 @endcode
  79
  80 Example:
  81
  82 @code
  83 <sensor name=\94aero/sensor/qbar\94 rate_group=\94HFCS\94>
  84   <input> aero/qbar </input>
  85   <lag> 0.5 </lag>
  86   <noise variation=\94PERCENT\94> 2 </noise>
  87   <quantization name="aero/sensor/quantized/qbar">
  88     <bits> 12 </bits>
  89     <min> 0 </min>
  90     <max> 400 </max>
  91   </quantization>
  92   <bias> 0.5 </bias>
  93 </sensor>
  94 @endcode
  95
  96 The only required element in the sensor definition is the input element. In that
  97 case, no degradation would be modeled, and the output would simply be the input.
  98
  99 For noise, if the type is PERCENT, then the value supplied is understood to be a
 100 percentage variance. That is, if the number given is 0.05, the the variance is
 101 understood to be +/-0.05 percent maximum variance. So, the actual value for the sensor
 102 will be *anywhere* from 0.95 to 1.05 of the actual "perfect" value at any time -
 103 even varying all the way from 0.95 to 1.05 in adjacent frames - whatever the delta
 104 time.
 105
 106 @author Jon S. Berndt
 107 @version $Revision$
 108 */
 109
 110 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 111 CLASS DECLARATION
 112 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 113
 114 class FGSensor  : public FGFCSComponent
 115 {
 116 public:
 117   FGSensor(FGFCS* fcs, Element* element);
 118   ~FGSensor();
 119
 120   inline void SetFailLow(double val) {if (val > 0.0) fail_low = true; else fail_low = false;}
 121   inline void SetFailHigh(double val) {if (val > 0.0) fail_high = true; else fail_high = false;}
 122   inline void SetFailStuck(double val) {if (val > 0.0) fail_stuck = true; else fail_stuck = false;}
 123
 124   inline double GetFailLow(void) const {if (fail_low) return 1.0; else return 0.0;}
 125   inline double GetFailHigh(void) const {if (fail_high) return 1.0; else return 0.0;}
 126   inline double GetFailStuck(void) const {if (fail_stuck) return 1.0; else return 0.0;}
 127
 128   bool Run (void);
 129
 130 private:
 131   enum eNoiseType {ePercent=0, eAbsolute} NoiseType;
 132   double dt;
 133   double min, max;
 134   double span;
 135   double bias;
 136   double drift_rate;
 137   double drift;
 138   double noise_variance;
 139   double lag;
 140   double granularity;
 141   double ca; /// lag filter coefficient "a"
 142   double cb; /// lag filter coefficient "b"
 143   double PreviousOutput;
 144   double PreviousInput;
 145   int noise_type;
 146   int bits;
 147   int quantized;
 148   int divisions;
 149   bool fail_low;
 150   bool fail_high;
 151   bool fail_stuck;
 152
 153   void Noise(void);
 154   void Bias(void);
 155   void Drift(void);
 156   void Quantize(void);
 157   void Lag(void);
 158
 159   void bind(void);
 160
 161   void Debug(int from);
 162 };
 163 }
 164 #endif