Added room in land_detector code for free-fall detection

src/modules/land_detector/FixedwingLandDetector.cpp

@@ -46,6 +46,9 @@
 #include <cmath>
 #include <drivers/drv_hrt.h>
 
+namespace landdetection
+{
+
 FixedwingLandDetector::FixedwingLandDetector() : LandDetector(),
 	_paramHandle(),
 	_params(),
@@ -84,11 +87,30 @@ void FixedwingLandDetector::updateSubscriptions()
 	orb_update(ORB_ID(airspeed), _airspeedSub, &_airspeed);
 }
 
-bool FixedwingLandDetector::update()
+LandDetectionResult FixedwingLandDetector::update()
 {
 	// First poll for new data from our subscriptions
 	updateSubscriptions();
 
+	if (get_freefall_state()) {
+		_state = LANDDETECTION_RES_FREEFALL;
+	}else if(get_landed_state()){
+		_state = LANDDETECTION_RES_LANDED;
+	}else{
+		_state = LANDDETECTION_RES_FLYING;
+	}
+
+	return _state;
+}
+
+bool FixedwingLandDetector::get_freefall_state()
+{
+	//TODO
+	return false;
+}
+
+bool FixedwingLandDetector::get_landed_state()
+{
 	// only trigger flight conditions if we are armed
 	if (!_arming.armed) {
 		return true;
@@ -159,3 +181,5 @@ void FixedwingLandDetector::updateParameterCache(const bool force)
 		param_get(_paramHandle.maxIntVelocity, &_params.maxIntVelocity);
 	}
 }
+
+}