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Dependencies: LSM9DS1 RangeFinder FastPWM
Dependents: PM2_Example_PES_board PM2_Example_PES_board PM2_Example_PES_board PM2_Example_PES_board ... more
Diff: SpeedController.cpp
- Revision:
- 3:8b42e643b294
- Child:
- 4:9c003c402033
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/SpeedController.cpp Thu Apr 01 14:31:43 2021 +0000
@@ -0,0 +1,79 @@
+#include "SpeedController.h"
+
+using namespace std;
+
+const float SpeedController::PERIOD = 0.001f; // period of 1 ms
+const float SpeedController::COUNTS_PER_TURN = 1560.0f; // encoder resolution
+const float SpeedController::LOWPASS_FILTER_FREQUENCY = 300.0f; // given in [rad/s]
+const float SpeedController::KN = 15.0f; // speed constant in [rpm/V]
+const float SpeedController::KP = 0.15f; // speed control parameter
+const float SpeedController::MAX_VOLTAGE = 12.0f; // battery voltage in [V]
+const float SpeedController::MIN_DUTY_CYCLE = 0.02f; // minimum duty-cycle
+const float SpeedController::MAX_DUTY_CYCLE = 0.98f; // maximum duty-cycle
+
+SpeedController::SpeedController(PwmOut& pwm, EncoderCounter& encoderCounter) : pwm(pwm), encoderCounter(encoderCounter), thread(osPriorityHigh, 4096)
+{
+
+ // Initialisieren der PWM Ausgaenge
+ pwm.period(0.00005f); // PWM Periode von 50 us
+ pwm = 0.5f; // Duty-Cycle von 50%
+
+ // Initialisieren von lokalen Variabeln
+ previousValueCounter = encoderCounter.read();
+ speedFilter.setPeriod(PERIOD);
+ speedFilter.setFrequency(LOWPASS_FILTER_FREQUENCY);
+ desiredSpeed = 0.0f;
+ actualSpeed = 0.0f;
+ actualAngle = 0.0f;
+
+ // Starten des periodischen Tasks
+ thread.start(callback(this, &SpeedController::run));
+ ticker.attach(callback(this, &SpeedController::sendThreadFlag), PERIOD);
+}
+
+SpeedController::~SpeedController()
+{
+ ticker.detach(); // Stoppt den periodischen Task
+}
+
+
+void SpeedController::setDesiredSpeed(float desiredSpeed)
+{
+ this->desiredSpeed = desiredSpeed;
+}
+
+float SpeedController::getSpeed()
+{
+ return actualSpeed;
+}
+
+void SpeedController::run()
+{
+ while(true) {
+
+ // wait for the periodic signal
+ ThisThread::flags_wait_any(threadFlag);
+
+ // calculate actual speed of motors in [rpm]
+ short valueCounter = encoderCounter.read();
+ short countsInPastPeriod = valueCounter-previousValueCounter;
+ previousValueCounter = valueCounter;
+ actualSpeed = speedFilter.filter((float)countsInPastPeriod/COUNTS_PER_TURN/PERIOD*60.0f);
+ actualAngle = actualAngle + actualSpeed/60.0f*PERIOD;
+
+ // calculate motor phase voltages
+ float voltage = KP*(desiredSpeed-actualSpeed)+desiredSpeed/KN;
+
+ // calculate, limit and set duty cycles
+ float dutyCycle = 0.5f+0.5f*voltage/MAX_VOLTAGE;
+ if (dutyCycle < MIN_DUTY_CYCLE) dutyCycle = MIN_DUTY_CYCLE;
+ else if (dutyCycle > MAX_DUTY_CYCLE) dutyCycle = MAX_DUTY_CYCLE;
+ pwm.write(dutyCycle);
+
+ }
+}
+
+void SpeedController::sendThreadFlag()
+{
+ thread.flags_set(threadFlag);
+}
\ No newline at end of file
