Merge remote-tracking branch 'upstream/master' into ros_messagelayer_merge

Conflicts:
	src/modules/attitude_estimator_ekf/attitude_estimator_ekf_main.cpp
	src/modules/uORB/topics/vehicle_attitude.h

9 files changed, 1050 insertions, 0 deletions

diff --git a/src/modules/land_detector/FixedwingLandDetector.cpp b/src/modules/land_detector/FixedwingLandDetector.cpp
new file mode 100644
index 000000000..8e5bcf7ba
--- /dev/null
+++ b/src/modules/land_detector/FixedwingLandDetector.cpp
@@ -0,0 +1,125 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file FixedwingLandDetector.cpp
+ * Land detection algorithm for fixedwings
+ *
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ */
+
+#include "FixedwingLandDetector.h"
+
+#include <cmath>
+#include <drivers/drv_hrt.h>
+
+FixedwingLandDetector::FixedwingLandDetector() : LandDetector(),
+	_paramHandle(),
+	_params(),
+	_vehicleLocalPositionSub(-1),
+	_vehicleLocalPosition({}),
+	_airspeedSub(-1),
+	_airspeed({}),
+	_parameterSub(-1),
+	_velocity_xy_filtered(0.0f),
+	_velocity_z_filtered(0.0f),
+	_airspeed_filtered(0.0f),
+	_landDetectTrigger(0)
+{
+	_paramHandle.maxVelocity = param_find("LNDFW_VEL_XY_MAX");
+	_paramHandle.maxClimbRate = param_find("LNDFW_VEL_Z_MAX");
+	_paramHandle.maxAirSpeed = param_find("LNDFW_AIRSPD_MAX");
+}
+
+void FixedwingLandDetector::initialize()
+{
+	// Subscribe to local position and airspeed data
+	_vehicleLocalPositionSub = orb_subscribe(ORB_ID(vehicle_local_position));
+	_airspeedSub = orb_subscribe(ORB_ID(airspeed));
+}
+
+void FixedwingLandDetector::updateSubscriptions()
+{
+	orb_update(ORB_ID(vehicle_local_position), _vehicleLocalPositionSub, &_vehicleLocalPosition);
+	orb_update(ORB_ID(airspeed), _airspeedSub, &_airspeed);
+}
+
+bool FixedwingLandDetector::update()
+{
+	// First poll for new data from our subscriptions
+	updateSubscriptions();
+
+	const uint64_t now = hrt_absolute_time();
+	bool landDetected = false;
+
+	// TODO: reset filtered values on arming?
+	_velocity_xy_filtered = 0.95f * _velocity_xy_filtered + 0.05f * sqrtf(_vehicleLocalPosition.vx *
+				_vehicleLocalPosition.vx + _vehicleLocalPosition.vy * _vehicleLocalPosition.vy);
+	_velocity_z_filtered = 0.95f * _velocity_z_filtered + 0.05f * fabsf(_vehicleLocalPosition.vz);
+	_airspeed_filtered = 0.95f * _airspeed_filtered + 0.05f * _airspeed.true_airspeed_m_s;
+
+	// crude land detector for fixedwing
+	if (_velocity_xy_filtered < _params.maxVelocity
+	    && _velocity_z_filtered < _params.maxClimbRate
+	    && _airspeed_filtered < _params.maxAirSpeed) {
+
+		// these conditions need to be stable for a period of time before we trust them
+		if (now > _landDetectTrigger) {
+			landDetected = true;
+		}
+
+	} else {
+		// reset land detect trigger
+		_landDetectTrigger = now + LAND_DETECTOR_TRIGGER_TIME;
+	}
+
+	return landDetected;
+}
+
+void FixedwingLandDetector::updateParameterCache(const bool force)
+{
+	bool updated;
+	parameter_update_s paramUpdate;
+
+	orb_check(_parameterSub, &updated);
+
+	if (updated) {
+		orb_copy(ORB_ID(parameter_update), _parameterSub, &paramUpdate);
+	}
+
+	if (updated || force) {
+		param_get(_paramHandle.maxVelocity, &_params.maxVelocity);
+		param_get(_paramHandle.maxClimbRate, &_params.maxClimbRate);
+		param_get(_paramHandle.maxAirSpeed, &_params.maxAirSpeed);
+	}
+}
diff --git a/src/modules/land_detector/FixedwingLandDetector.h b/src/modules/land_detector/FixedwingLandDetector.h
new file mode 100644
index 000000000..0e9c092ee
--- /dev/null
+++ b/src/modules/land_detector/FixedwingLandDetector.h
@@ -0,0 +1,105 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file FixedwingLandDetector.h
+ * Land detection algorithm for fixedwing
+ *
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ */
+
+#ifndef __FIXED_WING_LAND_DETECTOR_H__
+#define __FIXED_WING_LAND_DETECTOR_H__
+
+#include "LandDetector.h"
+#include <uORB/topics/vehicle_local_position.h>
+#include <uORB/topics/airspeed.h>
+#include <uORB/topics/parameter_update.h>
+#include <systemlib/param/param.h>
+
+class FixedwingLandDetector : public LandDetector
+{
+public:
+	FixedwingLandDetector();
+
+protected:
+	/**
+	* @brief  blocking loop, should be run in a separate thread or task. Runs at 50Hz
+	**/
+	bool update() override;
+
+	/**
+	* @brief Initializes the land detection algorithm
+	**/
+	void initialize() override;
+
+	/**
+	* @brief  polls all subscriptions and pulls any data that has changed
+	**/
+	void updateSubscriptions();
+
+private:
+	/**
+	* @brief download and update local parameter cache
+	**/
+	void updateParameterCache(const bool force);
+
+	/**
+	* @brief Handles for interesting parameters
+	**/
+	struct {
+		param_t maxVelocity;
+		param_t maxClimbRate;
+		param_t maxAirSpeed;
+	}		_paramHandle;
+
+	struct {
+		float maxVelocity;
+		float maxClimbRate;
+		float maxAirSpeed;
+	} _params;
+
+private:
+	int                                     _vehicleLocalPositionSub;   /**< notification of local position */
+	struct vehicle_local_position_s         _vehicleLocalPosition;      /**< the result from local position subscription */
+	int                                     _airspeedSub;
+	struct airspeed_s                       _airspeed;
+	int 									_parameterSub;
+
+	float _velocity_xy_filtered;
+	float _velocity_z_filtered;
+	float _airspeed_filtered;
+	uint64_t _landDetectTrigger;
+};
+
+#endif //__FIXED_WING_LAND_DETECTOR_H__
diff --git a/src/modules/land_detector/LandDetector.cpp b/src/modules/land_detector/LandDetector.cpp
new file mode 100644
index 000000000..a4fbb9861
--- /dev/null
+++ b/src/modules/land_detector/LandDetector.cpp
@@ -0,0 +1,124 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file LandDetector.cpp
+ * Land detection algorithm
+ *
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ * @author Morten Lysgaard <morten@lysgaard.no>
+ */
+
+#include "LandDetector.h"
+#include <unistd.h>                 //usleep
+#include <drivers/drv_hrt.h>
+
+LandDetector::LandDetector() :
+	_landDetectedPub(-1),
+	_landDetected({0, false}),
+	_taskShouldExit(false),
+	_taskIsRunning(false)
+{
+	// ctor
+}
+
+LandDetector::~LandDetector()
+{
+	_taskShouldExit = true;
+	close(_landDetectedPub);
+}
+
+void LandDetector::shutdown()
+{
+	_taskShouldExit = true;
+}
+
+void LandDetector::start()
+{
+	// make sure this method has not already been called by another thread
+	if (isRunning()) {
+		return;
+	}
+
+	// advertise the first land detected uORB
+	_landDetected.timestamp = hrt_absolute_time();
+	_landDetected.landed = false;
+	_landDetectedPub = orb_advertise(ORB_ID(vehicle_land_detected), &_landDetected);
+
+	// initialize land detection algorithm
+	initialize();
+
+	// task is now running, keep doing so until shutdown() has been called
+	_taskIsRunning = true;
+	_taskShouldExit = false;
+
+	while (isRunning()) {
+
+		bool landDetected = update();
+
+		// publish if land detection state has changed
+		if (_landDetected.landed != landDetected) {
+			_landDetected.timestamp = hrt_absolute_time();
+			_landDetected.landed = landDetected;
+
+			// publish the land detected broadcast
+			orb_publish(ORB_ID(vehicle_land_detected), _landDetectedPub, &_landDetected);
+		}
+
+		// limit loop rate
+		usleep(1000000 / LAND_DETECTOR_UPDATE_RATE);
+	}
+
+	_taskIsRunning = false;
+	_exit(0);
+}
+
+bool LandDetector::orb_update(const struct orb_metadata *meta, int handle, void *buffer)
+{
+	bool newData = false;
+
+	// check if there is new data to grab
+	if (orb_check(handle, &newData) != OK) {
+		return false;
+	}
+
+	if (!newData) {
+		return false;
+	}
+
+	if (orb_copy(meta, handle, buffer) != OK) {
+		return false;
+	}
+
+	return true;
+}
diff --git a/src/modules/land_detector/LandDetector.h b/src/modules/land_detector/LandDetector.h
new file mode 100644
index 000000000..09db6e474
--- /dev/null
+++ b/src/modules/land_detector/LandDetector.h
@@ -0,0 +1,104 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file LandDetector.h
+ * Abstract interface for land detector algorithms
+ *
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ */
+
+#ifndef __LAND_DETECTOR_H__
+#define __LAND_DETECTOR_H__
+
+#include <uORB/uORB.h>
+#include <uORB/topics/vehicle_land_detected.h>
+
+class LandDetector
+{
+public:
+
+	LandDetector();
+	virtual ~LandDetector();
+
+	/**
+	* @return true if this task is currently running
+	**/
+	inline bool isRunning() const {return _taskIsRunning;}
+
+	/**
+	* @brief  Tells the Land Detector task that it should exit
+	**/
+	void shutdown();
+
+	/**
+	* @brief Blocking function that should be called from it's own task thread. This method will
+	*        run the underlying algorithm at the desired update rate and publish if the landing state changes.
+	**/
+	void start();
+
+protected:
+
+	/**
+	* @brief Pure abstract method that must be overriden by sub-classes. This actually runs the underlying algorithm
+	* @return true if a landing was detected and this should be broadcast to the rest of the system
+	**/
+	virtual bool update() = 0;
+
+	/**
+	* @brief Pure abstract method that is called by this class once for initializing the uderlying algorithm (memory allocation,
+	*        uORB topic subscription, creating file descriptors, etc.)
+	**/
+	virtual void initialize() = 0;
+
+	/**
+	* @brief Convinience function for polling uORB subscriptions
+	* @return true if there was new data and it was successfully copied
+	**/
+	bool orb_update(const struct orb_metadata *meta, int handle, void *buffer);
+
+	static constexpr uint32_t LAND_DETECTOR_UPDATE_RATE = 50;        /**< Run algorithm at 50Hz */
+
+	static constexpr uint64_t LAND_DETECTOR_TRIGGER_TIME = 2000000;  /**< usec that landing conditions have to hold
+                                                                          before triggering a land */
+
+protected:
+	orb_advert_t                            _landDetectedPub;           /**< publisher for position in local frame */
+	struct vehicle_land_detected_s          _landDetected;              /**< local vehicle position */
+
+private:
+	bool _taskShouldExit;                                               /**< true if it is requested that this task should exit */
+	bool _taskIsRunning;                                                /**< task has reached main loop and is currently running */
+};
+
+#endif //__LAND_DETECTOR_H__
diff --git a/src/modules/land_detector/MulticopterLandDetector.cpp b/src/modules/land_detector/MulticopterLandDetector.cpp
new file mode 100644
index 000000000..277cb9363
--- /dev/null
+++ b/src/modules/land_detector/MulticopterLandDetector.cpp
@@ -0,0 +1,145 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file MulticopterLandDetector.cpp
+ * Land detection algorithm for multicopters
+ *
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ * @author Morten Lysgaard <morten@lysgaard.no>
+ */
+
+#include "MulticopterLandDetector.h"
+
+#include <cmath>
+#include <drivers/drv_hrt.h>
+
+MulticopterLandDetector::MulticopterLandDetector() : LandDetector(),
+	_paramHandle(),
+	_params(),
+	_vehicleGlobalPositionSub(-1),
+	_sensorsCombinedSub(-1),
+	_waypointSub(-1),
+	_actuatorsSub(-1),
+	_armingSub(-1),
+	_parameterSub(-1),
+	_vehicleGlobalPosition({}),
+	_sensors({}),
+	_waypoint({}),
+	_actuators({}),
+	_arming({}),
+	_landTimer(0)
+{
+	_paramHandle.maxRotation = param_find("LNDMC_Z_VEL_MAX");
+	_paramHandle.maxVelocity = param_find("LNDMC_XY_VEL_MAX");
+	_paramHandle.maxClimbRate = param_find("LNDMC_ROT_MAX");
+	_paramHandle.maxThrottle = param_find("LNDMC_THR_MAX");
+}
+
+void MulticopterLandDetector::initialize()
+{
+	// subscribe to position, attitude, arming and velocity changes
+	_vehicleGlobalPositionSub = orb_subscribe(ORB_ID(vehicle_global_position));
+	_sensorsCombinedSub = orb_subscribe(ORB_ID(sensor_combined));
+	_waypointSub = orb_subscribe(ORB_ID(position_setpoint_triplet));
+	_actuatorsSub = orb_subscribe(ORB_ID_VEHICLE_ATTITUDE_CONTROLS);
+	_armingSub = orb_subscribe(ORB_ID(actuator_armed));
+	_parameterSub = orb_subscribe(ORB_ID(parameter_update));
+
+	// download parameters
+	updateParameterCache(true);
+}
+
+void MulticopterLandDetector::updateSubscriptions()
+{
+	orb_update(ORB_ID(vehicle_global_position), _vehicleGlobalPositionSub, &_vehicleGlobalPosition);
+	orb_update(ORB_ID(sensor_combined), _sensorsCombinedSub, &_sensors);
+	orb_update(ORB_ID(position_setpoint_triplet), _waypointSub, &_waypoint);
+	orb_update(ORB_ID_VEHICLE_ATTITUDE_CONTROLS, _actuatorsSub, &_actuators);
+	orb_update(ORB_ID(actuator_armed), _armingSub, &_arming);
+}
+
+bool MulticopterLandDetector::update()
+{
+	// first poll for new data from our subscriptions
+	updateSubscriptions();
+
+	// only trigger flight conditions if we are armed
+	if (!_arming.armed) {
+		return true;
+	}
+
+	const uint64_t now = hrt_absolute_time();
+
+	// check if we are moving vertically
+	bool verticalMovement = fabsf(_vehicleGlobalPosition.vel_d) > _params.maxClimbRate;
+
+	// check if we are moving horizontally
+	bool horizontalMovement = sqrtf(_vehicleGlobalPosition.vel_n * _vehicleGlobalPosition.vel_n
+					+ _vehicleGlobalPosition.vel_e * _vehicleGlobalPosition.vel_e) > _params.maxVelocity;
+
+	// next look if all rotation angles are not moving
+	bool rotating = sqrtf(_sensors.gyro_rad_s[0] * _sensors.gyro_rad_s[0] +
+			      _sensors.gyro_rad_s[1] * _sensors.gyro_rad_s[1] +
+			      _sensors.gyro_rad_s[2] * _sensors.gyro_rad_s[2]) > _params.maxRotation;
+
+	// check if thrust output is minimal (about half of default)
+	bool minimalThrust = _actuators.control[3] <= _params.maxThrottle;
+
+	if (verticalMovement || rotating || !minimalThrust || horizontalMovement) {
+		// sensed movement, so reset the land detector
+		_landTimer = now;
+		return false;
+	}
+
+	return now - _landTimer > LAND_DETECTOR_TRIGGER_TIME;
+}
+
+void MulticopterLandDetector::updateParameterCache(const bool force)
+{
+	bool updated;
+	parameter_update_s paramUpdate;
+
+	orb_check(_parameterSub, &updated);
+
+	if (updated) {
+		orb_copy(ORB_ID(parameter_update), _parameterSub, &paramUpdate);
+	}
+
+	if (updated || force) {
+		param_get(_paramHandle.maxClimbRate, &_params.maxClimbRate);
+		param_get(_paramHandle.maxVelocity, &_params.maxVelocity);
+		param_get(_paramHandle.maxRotation, &_params.maxRotation);
+		param_get(_paramHandle.maxThrottle, &_params.maxThrottle);
+	}
+}
diff --git a/src/modules/land_detector/MulticopterLandDetector.h b/src/modules/land_detector/MulticopterLandDetector.h
new file mode 100644
index 000000000..7bb7f1a90
--- /dev/null
+++ b/src/modules/land_detector/MulticopterLandDetector.h
@@ -0,0 +1,116 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file MulticopterLandDetector.h
+ * Land detection algorithm for multicopters
+ *
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ * @author Morten Lysgaard <morten@lysgaard.no>
+ */
+
+#ifndef __MULTICOPTER_LAND_DETECTOR_H__
+#define __MULTICOPTER_LAND_DETECTOR_H__
+
+#include "LandDetector.h"
+#include <uORB/topics/vehicle_global_position.h>
+#include <uORB/topics/sensor_combined.h>
+#include <uORB/topics/position_setpoint_triplet.h>
+#include <uORB/topics/actuator_controls.h>
+#include <uORB/topics/actuator_armed.h>
+#include <uORB/topics/parameter_update.h>
+#include <systemlib/param/param.h>
+
+class MulticopterLandDetector : public LandDetector
+{
+public:
+	MulticopterLandDetector();
+
+protected:
+	/**
+	* @brief  polls all subscriptions and pulls any data that has changed
+	**/
+	void updateSubscriptions();
+
+	/**
+	* @brief Runs one iteration of the land detection algorithm
+	**/
+	bool update() override;
+
+	/**
+	* @brief Initializes the land detection algorithm
+	**/
+	void initialize() override;
+
+
+private:
+	/**
+	* @brief download and update local parameter cache
+	**/
+	void updateParameterCache(const bool force);
+
+	/**
+	* @brief Handles for interesting parameters
+	**/
+	struct {
+		param_t maxClimbRate;
+		param_t maxVelocity;
+		param_t maxRotation;
+		param_t maxThrottle;
+	}		_paramHandle;
+
+	struct {
+		float maxClimbRate;
+		float maxVelocity;
+		float maxRotation;
+		float maxThrottle;
+	} _params;
+
+private:
+	int _vehicleGlobalPositionSub;                                      /**< notification of global position */
+	int _sensorsCombinedSub;
+	int _waypointSub;
+	int _actuatorsSub;
+	int _armingSub;
+	int _parameterSub;
+
+	struct vehicle_global_position_s          _vehicleGlobalPosition;   /**< the result from global position subscription */
+	struct sensor_combined_s                  _sensors;                 /**< subscribe to sensor readings */
+	struct position_setpoint_triplet_s        _waypoint;                /**< subscribe to autopilot navigation */
+	struct actuator_controls_s                _actuators;
+	struct actuator_armed_s                   _arming;
+
+	uint64_t _landTimer;                                                /**< timestamp in microseconds since a possible land was detected*/
+};
+
+#endif //__MULTICOPTER_LAND_DETECTOR_H__
diff --git a/src/modules/land_detector/land_detector_main.cpp b/src/modules/land_detector/land_detector_main.cpp
new file mode 100644
index 000000000..1e43e7ad5
--- /dev/null
+++ b/src/modules/land_detector/land_detector_main.cpp
@@ -0,0 +1,214 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013-2015 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file land_detector_main.cpp
+ * Land detection algorithm
+ *
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ */
+
+#include <unistd.h>					//usleep
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <drivers/drv_hrt.h>
+#include <systemlib/systemlib.h>	//Scheduler
+#include <systemlib/err.h>			//print to console
+
+#include "FixedwingLandDetector.h"
+#include "MulticopterLandDetector.h"
+
+//Function prototypes
+static int land_detector_start(const char *mode);
+static void land_detector_stop();
+
+/**
+ * land detector app start / stop handling function
+ * This makes the land detector module accessible from the nuttx shell
+ * @ingroup apps
+ */
+extern "C" __EXPORT int land_detector_main(int argc, char *argv[]);
+
+//Private variables
+static LandDetector *land_detector_task = nullptr;
+static int _landDetectorTaskID = -1;
+static char _currentMode[12];
+
+/**
+* Deamon thread function
+**/
+static void land_detector_deamon_thread(int argc, char *argv[])
+{
+	land_detector_task->start();
+}
+
+/**
+* Stop the task, force killing it if it doesn't stop by itself
+**/
+static void land_detector_stop()
+{
+	if (land_detector_task == nullptr || _landDetectorTaskID == -1) {
+		errx(1, "not running");
+		return;
+	}
+
+	land_detector_task->shutdown();
+
+	//Wait for task to die
+	int i = 0;
+
+	do {
+		/* wait 20ms */
+		usleep(20000);
+
+		/* if we have given up, kill it */
+		if (++i > 50) {
+			task_delete(_landDetectorTaskID);
+			break;
+		}
+	} while (land_detector_task->isRunning());
+
+
+	delete land_detector_task;
+	land_detector_task = nullptr;
+	_landDetectorTaskID = -1;
+	errx(0, "land_detector has been stopped");
+}
+
+/**
+* Start new task, fails if it is already running. Returns OK if successful
+**/
+static int land_detector_start(const char *mode)
+{
+	if (land_detector_task != nullptr || _landDetectorTaskID != -1) {
+		errx(1, "already running");
+		return -1;
+	}
+
+	//Allocate memory
+	if (!strcmp(mode, "fixedwing")) {
+		land_detector_task = new FixedwingLandDetector();
+
+	} else if (!strcmp(mode, "multicopter")) {
+		land_detector_task = new MulticopterLandDetector();
+
+	} else {
+		errx(1, "[mode] must be either 'fixedwing' or 'multicopter'");
+		return -1;
+	}
+
+	//Check if alloc worked
+	if (land_detector_task == nullptr) {
+		errx(1, "alloc failed");
+		return -1;
+	}
+
+	//Start new thread task
+	_landDetectorTaskID = task_spawn_cmd("land_detector",
+					     SCHED_DEFAULT,
+					     SCHED_PRIORITY_DEFAULT,
+					     1200,
+					     (main_t)&land_detector_deamon_thread,
+					     nullptr);
+
+	if (_landDetectorTaskID < 0) {
+		errx(1, "task start failed: %d", -errno);
+		return -1;
+	}
+
+	/* avoid memory fragmentation by not exiting start handler until the task has fully started */
+	const uint32_t timeout = hrt_absolute_time() + 5000000; //5 second timeout
+
+	while (!land_detector_task->isRunning()) {
+		usleep(50000);
+		printf(".");
+		fflush(stdout);
+
+		if (hrt_absolute_time() > timeout) {
+			err(1, "start failed - timeout");
+			land_detector_stop();
+			exit(1);
+		}
+	}
+
+	printf("\n");
+
+	//Remember current active mode
+	strncpy(_currentMode, mode, 12);
+
+	exit(0);
+	return 0;
+}
+
+/**
+* Main entry point for this module
+**/
+int land_detector_main(int argc, char *argv[])
+{
+
+	if (argc < 1) {
+		warnx("usage: land_detector {start|stop|status} [mode]\nmode can either be 'fixedwing' or 'multicopter'");
+		exit(0);
+	}
+
+	if (argc >= 2 && !strcmp(argv[1], "start")) {
+		land_detector_start(argv[2]);
+	}
+
+	if (!strcmp(argv[1], "stop")) {
+		land_detector_stop();
+		exit(0);
+	}
+
+	if (!strcmp(argv[1], "status")) {
+		if (land_detector_task) {
+
+			if (land_detector_task->isRunning()) {
+				warnx("running (%s)", _currentMode);
+
+			} else {
+				errx(1, "exists, but not running (%s)", _currentMode);
+			}
+
+			exit(0);
+
+		} else {
+			errx(1, "not running");
+		}
+	}
+
+	warn("usage: land_detector {start|stop|status} [mode]\nmode can either be 'fixedwing' or 'multicopter'");
+	return 1;
+}
diff --git a/src/modules/land_detector/land_detector_params.c b/src/modules/land_detector/land_detector_params.c
new file mode 100644
index 000000000..0302bc7c1
--- /dev/null
+++ b/src/modules/land_detector/land_detector_params.c
@@ -0,0 +1,104 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014, 2015 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file land_detector.c
+ * Land detector algorithm parameters.
+ *
+ * @author Johan Jansen <jnsn.johan@gmail.com>
+ */
+
+#include <systemlib/param/param.h>
+
+/**
+ * Multicopter max climb rate
+ *
+ * Maximum vertical velocity allowed to trigger a land (m/s up and down)
+ *
+ * @group Land Detector
+ */
+PARAM_DEFINE_FLOAT(LNDMC_Z_VEL_MAX, 0.30f);
+
+/**
+ * Multicopter max horizontal velocity
+ *
+ * Maximum horizontal velocity allowed to trigger a land (m/s)
+ *
+ * @group Land Detector
+ */
+PARAM_DEFINE_FLOAT(LNDMC_XY_VEL_MAX, 1.00f);
+
+/**
+ * Multicopter max rotation
+ *
+ * Maximum allowed around each axis to trigger a land (radians per second)
+ *
+ * @group Land Detector
+ */
+PARAM_DEFINE_FLOAT(LNDMC_ROT_MAX, 0.20f);
+
+/**
+ * Multicopter max throttle
+ *
+ * Maximum actuator output on throttle before triggering a land
+ *
+ * @group Land Detector
+ */
+PARAM_DEFINE_FLOAT(LNDMC_THR_MAX, 0.20f);
+
+/**
+ * Fixedwing max horizontal velocity
+ *
+ * Maximum horizontal velocity allowed to trigger a land (m/s)
+ *
+ * @group Land Detector
+ */
+PARAM_DEFINE_FLOAT(LNDFW_VEL_XY_MAX, 0.20f);
+
+/**
+ * Fixedwing max climb rate
+ *
+ * Maximum vertical velocity allowed to trigger a land (m/s up and down)
+ *
+ * @group Land Detector
+ */
+PARAM_DEFINE_FLOAT(LNDFW_VEL_Z_MAX, 10.00f);
+
+/**
+ * Airspeed max
+ *
+ * Maximum airspeed allowed to trigger a land (m/s)
+ *
+ * @group Land Detector
+ */
+PARAM_DEFINE_FLOAT(LNDFW_AIRSPD_MAX, 10.00f);
diff --git a/src/modules/land_detector/module.mk b/src/modules/land_detector/module.mk
new file mode 100644
index 000000000..e08a4b7a8
--- /dev/null
+++ b/src/modules/land_detector/module.mk
@@ -0,0 +1,13 @@
+#
+# Land detector
+#
+
+MODULE_COMMAND	= land_detector
+
+SRCS		= land_detector_main.cpp \
+              land_detector_params.c \
+              LandDetector.cpp \
+			  MulticopterLandDetector.cpp \
+              FixedwingLandDetector.cpp
+
+EXTRACXXFLAGS   = -Weffc++ -Os