SpeedControl.h

00001 /*
00002  * SpeedControl.h
00003  */
00004 
00005 #ifndef SPEED_CONTROL_H_
00006 #define SPEED_CONTROL_H_
00007 
00008 #include <cstdlib>
00009 #include <mbed.h>
00010 #include "EncoderCounter.h"
00011 #include "LowpassFilter.h"
00012 
00013 class SpeedControl
00014 {
00015 
00016 public:
00017 
00018                 SpeedControl(PwmOut* pwmLeft, PwmOut* pwmRight, EncoderCounter* counterLeft, EncoderCounter* counterRight);     // constructor  
00019     virtual     ~SpeedControl();        //destructor    
00020     
00021     void        speedCtrl();
00022     void        setDesiredSpeed( float L, float R);
00023 
00024     LowpassFilter speedLeftFilter;
00025     LowpassFilter speedRightFilter;
00026 
00027 private:
00028 
00029     //static allows you to initialize variables within the header
00030     static const float PERIOD = 0.002f;                    // period of control task, given in [s]
00031     static const float COUNTS_PER_TURN = 1200.0f;          // resolution of encoder counter
00032     static const float LOWPASS_FILTER_FREQUENCY = 300.0f;  // frequency of lowpass filter for actual speed values, given in [rad/s]
00033     static const float KN = 40.0f;                         // speed constant of motor, given in [rpm/V]
00034     static const float KP = 0.2f;                          // speed controller gain, given in [V/rpm]
00035     //static const float KI = 0.1f;                          //speed controller integral term gain [V/rpm]
00036     static const float MAX_VOLTAGE = 12.0f;                // supply voltage for power stage in [V]
00037     static const float MIN_DUTY_CYCLE = 0.02f;             // minimum allowed value for duty cycle (2%)
00038     static const float MAX_DUTY_CYCLE = 0.98f;             // maximum allowed value for duty cycle (98%)
00039 
00040     DigitalOut* enableMotorDriver;
00041     PwmOut* pwmLeft;
00042     PwmOut* pwmRight;
00043     EncoderCounter* counterRight;
00044     EncoderCounter* counterLeft;
00045     Ticker t2;
00046 
00047     short previousValueCounterRight ;  // was = 0
00048     short previousValueCounterLeft;     // same
00049 
00050     float desiredSpeedLeft;
00051     float desiredSpeedRight;
00052 
00053     float actualSpeedLeft;
00054     float actualSpeedRight;
00055 };
00056 
00057 #endif /* SPEED_CONTROL_H_ */