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Pid.h
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2 // Copyright (c) 2009, Markus Rickert
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29 
30 #ifndef _RL_MATH_PID_H_
31 #define _RL_MATH_PID_H_
32 
33 #include "Real.h"
34 
35 namespace rl
36 {
37  namespace math
38  {
42  template< typename T >
43  class Pid
44  {
45  public:
46  Pid() :
47  e(0),
48  kd(0),
49  ki(0),
50  kp(0),
51  i(0)
52  {
53 
54  }
55 
56  virtual ~Pid()
57  {
58 
59  }
60 
66  T operator()(const T& x, const Real& dt)
67  {
68  T e = this->x - x;
69  T p = this->kp * e;
70  this->i += this->ki * e * dt;
71  T d = this->kd * (e - this->e) / dt;
72  this->e = e;
73  return x + p + this->i + d;
74  }
75 
76  void reset()
77  {
78  this->e = 0;
79  this->i = 0;
80  }
81 
83  T kd;
84 
86  T ki;
87 
89  T kp;
90 
92  T x;
93 
94  protected:
95 
96  private:
98  T e;
99 
101  T i;
102  };
103  }
104 }
105 
106 #endif // _RL_MATH_PID_H_