heater: fix on blips when the heater is off (#25398)

Co-authored-by: Jacob Dahl <37091262+dakejahl@users.noreply.github.com>

Author: AlexKlimaj

src/drivers/heater/heater.cpp

@@ -201,7 +201,7 @@ void Heater::Run()
 		// Turn the heater off.
 		_heater_on = false;
 		heater_off();
-		ScheduleDelayed(_controller_period_usec - _controller_time_on_usec);
+		ScheduleDelayed(CONTROLLER_PERIOD_DEFAULT - _controller_time_on_usec);
 
 	} else if (_sensor_accel_sub.update(&sensor_accel)) {
 
@@ -217,9 +217,9 @@ void Heater::Run()
 		_integrator_value = math::constrain(_integrator_value, -0.25f, 0.25f);
 
 		_controller_time_on_usec = static_cast<int>((_param_sens_imu_temp_ff.get() + _proportional_value +
-					   _integrator_value) * static_cast<float>(_controller_period_usec));
+					   _integrator_value) * static_cast<float>(CONTROLLER_PERIOD_DEFAULT));
 
-		_controller_time_on_usec = math::constrain(_controller_time_on_usec, 0, _controller_period_usec);
+		_controller_time_on_usec = math::constrain(_controller_time_on_usec, 0, CONTROLLER_PERIOD_DEFAULT);
 
 		if (fabsf(temperature_delta) < TEMPERATURE_TARGET_THRESHOLD) {
 			_temperature_target_met = true;
@@ -229,9 +229,16 @@ void Heater::Run()
 			_temperature_target_met = false;
 		}
 
-		_heater_on = true;
-		heater_on();
-		ScheduleDelayed(_controller_time_on_usec);
+		if (_controller_time_on_usec > 0) {
+			// Turn the heater on.
+			_heater_on = true;
+			heater_on();
+			ScheduleDelayed(_controller_time_on_usec);
+
+		} else {
+			// Turn the heater off.
+			ScheduleDelayed(CONTROLLER_PERIOD_DEFAULT);
+		}
 	}
 
 	publish_status();
@@ -245,7 +252,7 @@ void Heater::publish_status()
 	status.temperature_sensor      = _temperature_last;
 	status.temperature_target      = _param_sens_imu_temp.get();
 	status.temperature_target_met  = _temperature_target_met;
-	status.controller_period_usec  = _controller_period_usec;
+	status.controller_period_usec  = CONTROLLER_PERIOD_DEFAULT;
 	status.controller_time_on_usec = _controller_time_on_usec;
 	status.proportional_value      = _proportional_value;
 	status.integrator_value        = _integrator_value;

src/drivers/heater/heater.h

@@ -142,7 +142,6 @@ class Heater : public ModuleBase<Heater>, public ModuleParams, public px4::Sched
 	bool _heater_on              = false;
 	bool _temperature_target_met = false;
 
-	int _controller_period_usec = CONTROLLER_PERIOD_DEFAULT;
 	int _controller_time_on_usec = 0;
 
 	float _integrator_value   = 0.0f;