a
Dependencies: mbed
main.cpp
- Committer:
- beacon
- Date:
- 2017-05-22
- Revision:
- 0:dfea4e0e064b
File content as of revision 0:dfea4e0e064b:
/* Folgendes Programm zeigt einen einfach P-Geschwindigkeitsregler Die DIP-Switch auf der Ruekseite des Roboters muessen dazu of "on" stehen. ACHTUNG: Die Motorencoder koennen nicht simultan mit den R/C-Servos gebraucht werden. */ #include "mbed.h" #include "EncoderCounter.h" #include "LowpassFilter.h" const float PERIOD = 0.001f; // period of control task, given in [s] const float COUNTS_PER_TURN = 1200.0f; // resolution of encoder counter const float LOWPASS_FILTER_FREQUENCY = 300.0f; // frequency of lowpass filter for actual speed values, given in [rad/s] const float KN = 40.0f; // speed constant of motor, given in [rpm/V] const float KP = 0.2f; // speed controller gain, given in [V/rpm] const float MAX_VOLTAGE = 12.0f; // supply voltage for power stage in [V] const float MIN_DUTY_CYCLE = 0.02f; // minimum allowed value for duty cycle (2%) const float MAX_DUTY_CYCLE = 0.98f; // maximum allowed value for duty cycle (98%) EncoderCounter counterLeft(PB_6, PB_7); EncoderCounter counterRight(PA_6, PC_7); LowpassFilter speedLeftFilter; LowpassFilter speedRightFilter; DigitalOut enableMotorDriver(PB_2); PwmOut pwmLeft(PA_8); PwmOut pwmRight(PA_9); DigitalOut my_led(LED1); short previousValueCounterRight = 0; short previousValueCounterLeft = 0; float desiredSpeedLeft; float desiredSpeedRight; float actualSpeedLeft; float actualSpeedRight; void speedCtrl() { // Berechnen die effektiven Drehzahlen der Motoren in [rpm] short valueCounterLeft = counterLeft.read(); short valueCounterRight = counterRight.read(); short countsInPastPeriodLeft = valueCounterLeft-previousValueCounterLeft; short countsInPastPeriodRight = valueCounterRight-previousValueCounterRight; previousValueCounterLeft = valueCounterLeft; previousValueCounterRight = valueCounterRight; actualSpeedLeft = speedLeftFilter.filter((float)countsInPastPeriodLeft /COUNTS_PER_TURN/PERIOD*60.0f); actualSpeedRight = speedRightFilter.filter((float)countsInPastPeriodRight /COUNTS_PER_TURN/PERIOD*60.0f); // Berechnen der Motorspannungen Uout float voltageLeft = KP*(desiredSpeedLeft-actualSpeedLeft)+desiredSpeedLeft/KN; float voltageRight = KP*(desiredSpeedRight-actualSpeedRight)+desiredSpeedRight/KN; // Berechnen, Limitieren und Setzen der Duty-Cycle float dutyCycleLeft = 0.5f+0.5f*voltageLeft/MAX_VOLTAGE; if (dutyCycleLeft < MIN_DUTY_CYCLE) dutyCycleLeft = MIN_DUTY_CYCLE; else if (dutyCycleLeft > MAX_DUTY_CYCLE) dutyCycleLeft = MAX_DUTY_CYCLE; pwmLeft = dutyCycleLeft; float dutyCycleRight = 0.5f+0.5f*voltageRight/MAX_VOLTAGE; if (dutyCycleRight < MIN_DUTY_CYCLE) dutyCycleRight = MIN_DUTY_CYCLE; else if (dutyCycleRight > MAX_DUTY_CYCLE) dutyCycleRight = MAX_DUTY_CYCLE; pwmRight = dutyCycleRight; } int main() { // Initialisieren der PWM Ausgaenge pwmLeft.period(0.00005f); // PWM Periode von 50 us pwmLeft.period(0.00005f); // Setzt die Periode auf 50 μs pwmRight.period(0.00005f); pwmLeft = 0.5f; // Duty-Cycle von 50% pwmRight.period(0.00005f); // PWM Periode von 50 us pwmRight = 0.5f; // Duty-Cycle von 50% // Initialisieren von lokalen Variabeln previousValueCounterLeft = counterLeft.read(); previousValueCounterRight = counterRight.read(); speedLeftFilter.setPeriod(PERIOD); speedLeftFilter.setFrequency(LOWPASS_FILTER_FREQUENCY); speedRightFilter.setPeriod(PERIOD); speedRightFilter.setFrequency(LOWPASS_FILTER_FREQUENCY); desiredSpeedLeft = 0.0f; desiredSpeedRight = 0.0f; actualSpeedLeft = 0.0f; actualSpeedRight = 0.0f; Ticker t1; t1.attach( &speedCtrl, PERIOD); desiredSpeedLeft = 50.0f; //50 RPM desiredSpeedRight = -50.0f; //50 RPM enableMotorDriver = 1; while(1) { my_led = !my_led; wait(0.5); } }