Merge pull request #2207 from mhkabir/cam_trig_new

Camera trigger WIP

makefiles/nuttx/config_px4fmu-v2_default.mk

@@ -73,6 +73,7 @@ MODULES		+= modules/mavlink
 MODULES		+= modules/gpio_led
 MODULES		+= modules/uavcan
 MODULES 	+= modules/land_detector
+MODULES		+= modules/camera_trigger
 
 #
 # Estimation modules (EKF/ SO3 / other filters)

msg/camera_trigger.msg

@@ -0,0 +1,4 @@
+
+uint64 timestamp	# Timestamp when camera was triggered
+uint32 seq		# Image sequence
+

msg/vehicle_command.msg

@@ -48,7 +48,8 @@ uint32 VEHICLE_CMD_PREFLIGHT_REBOOT_SHUTDOWN = 246	# Request the reboot or shutd
 uint32 VEHICLE_CMD_OVERRIDE_GOTO = 252			# Hold / continue the current action |MAV_GOTO_DO_HOLD: hold MAV_GOTO_DO_CONTINUE: continue with next item in mission plan| MAV_GOTO_HOLD_AT_CURRENT_POSITION: Hold at current position MAV_GOTO_HOLD_AT_SPECIFIED_POSITION: hold at specified position| MAV_FRAME coordinate frame of hold point| Desired yaw angle in degrees| Latitude / X position| Longitude / Y position| Altitude / Z position| 
 uint32 VEHICLE_CMD_MISSION_START = 300			# start running a mission |first_item: the first mission item to run| last_item:  the last mission item to run (after this item is run, the mission ends)| 
 uint32 VEHICLE_CMD_COMPONENT_ARM_DISARM = 400		# Arms / Disarms a component |1 to arm, 0 to disarm| 
-uint32 VEHICLE_CMD_START_RX_PAIR = 500			# Starts receiver pairing |0:Spektrum| 0:Spektrum DSM2, 1:Spektrum DSMX| 
+uint32 VEHICLE_CMD_START_RX_PAIR = 500			# Starts receiver pairing |0:Spektrum| 0:Spektrum DSM2, 1:Spektrum DSMX|
+uint32 VEHICLE_CMD_DO_TRIGGER_CONTROL = 2003            # Enable or disable on-board camera triggering system
 uint32 VEHICLE_CMD_PAYLOAD_PREPARE_DEPLOY = 30001	# Prepare a payload deployment in the flight plan
 uint32 VEHICLE_CMD_PAYLOAD_CONTROL_DEPLOY = 30002	# Control a pre-programmed payload deployment
 

src/modules/camera_trigger/camera_trigger.cpp

@@ -0,0 +1,392 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2015 PX4 Development Team. All rights reserved.
+ *   Author: Mohammed Kabir <mhkabir98@gmail.com>
+ *
+ * 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 camera_trigger.cpp
+ *
+ * External camera-IMU synchronisation and triggering via FMU auxillary pins.
+ *
+ * @author Mohammed Kabir <mhkabir98@gmail.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <nuttx/clock.h>
+#include <nuttx/arch.h>
+#include <systemlib/systemlib.h>
+#include <systemlib/err.h>
+#include <systemlib/param/param.h>
+#include <uORB/uORB.h>
+#include <uORB/topics/camera_trigger.h>
+#include <uORB/topics/sensor_combined.h>
+#include <uORB/topics/vehicle_command.h>
+#include <poll.h>
+#include <drivers/drv_gpio.h>
+#include <drivers/drv_hrt.h>
+#include <mavlink/mavlink_log.h>
+#include <board_config.h>
+
+extern "C" __EXPORT int camera_trigger_main(int argc, char *argv[]);
+
+class CameraTrigger
+{
+public:
+	/**
+	 * Constructor
+	 */
+	CameraTrigger();
+
+	/**
+	 * Destructor, also kills task.
+	 */
+	~CameraTrigger();
+
+	/**
+	 * Start the task.
+	 */
+	void		start();
+
+	/**
+	 * Stop the task.
+	 */
+	void		stop();
+
+	/**
+	 * Display info.
+	 */
+	void		info();
+		
+	int 		pin;
+	
+private:
+	
+	struct hrt_call		_pollcall;
+	struct hrt_call		_firecall;
+	
+	int 			_gpio_fd;
+
+	int 			_polarity;
+	float 			_activation_time;
+	float  			_integration_time;
+	float  			_transfer_time;
+	uint32_t 		_trigger_seq;		
+	bool	 		_trigger_enabled;
+
+	int			_sensor_sub;
+	int			_vcommand_sub;
+
+	orb_advert_t		_trigger_pub;
+
+	struct camera_trigger_s		_trigger;
+	struct sensor_combined_s	_sensor;
+	struct vehicle_command_s	_command;
+
+	param_t polarity ;
+	param_t activation_time ;	
+	param_t integration_time ;
+	param_t transfer_time ;
+	
+	/**
+	 * Topic poller to check for fire info.
+	 */
+	static void	poll(void *arg);
+	/**
+	 * Fires trigger
+	 */
+	static void	engage(void *arg);
+	/**
+	 * Resets trigger
+	 */
+	static void	disengage(void *arg);
+
+};
+
+namespace camera_trigger
+{
+
+CameraTrigger	*g_camera_trigger;
+}
+
+CameraTrigger::CameraTrigger() :
+	pin(1),
+	_pollcall{},
+	_firecall{},
+	_gpio_fd(-1),
+	_polarity(0),
+	_activation_time(0.0f),
+	_integration_time(0.0f),
+	_transfer_time(0.0f),
+	_trigger_seq(0),
+	_trigger_enabled(false),
+	_sensor_sub(-1),
+	_vcommand_sub(-1),
+	_trigger_pub(nullptr),
+	_trigger{},
+	_sensor{},
+	_command{}
+{
+	memset(&_trigger, 0, sizeof(_trigger));
+	memset(&_sensor, 0, sizeof(_sensor));
+	memset(&_command, 0, sizeof(_command));
+	
+	memset(&_pollcall, 0, sizeof(_pollcall));
+	memset(&_firecall, 0, sizeof(_firecall));	
+
+	// Parameters
+	polarity = param_find("TRIG_POLARITY");
+	activation_time = param_find("TRIG_ACT_TIME");	
+	integration_time = param_find("TRIG_INT_TIME");
+	transfer_time = param_find("TRIG_TRANS_TIME");
+}
+
+CameraTrigger::~CameraTrigger()
+{
+	camera_trigger::g_camera_trigger = nullptr;
+}
+
+void
+CameraTrigger::start()
+{
+
+	_sensor_sub = orb_subscribe(ORB_ID(sensor_combined));
+	_vcommand_sub = orb_subscribe(ORB_ID(vehicle_command));
+	
+	param_get(polarity, &_polarity); 
+	param_get(activation_time, &_activation_time);	
+	param_get(integration_time, &_integration_time); 	
+	param_get(transfer_time, &_transfer_time); 
+	
+	stm32_configgpio(GPIO_GPIO0_OUTPUT);
+
+	if(_polarity == 0) {
+		stm32_gpiowrite(GPIO_GPIO0_OUTPUT, 1);	 	// GPIO pin pull high
+	}
+	else if(_polarity == 1) {
+		stm32_gpiowrite(GPIO_GPIO0_OUTPUT, 0);	 	// GPIO pin pull low
+	}	
+	else {
+		warnx(" invalid trigger polarity setting. stopping.");
+		stop();
+	}
+	
+	poll(this);	// Trampoline call
+
+}
+
+void
+CameraTrigger::stop()
+{	
+	hrt_cancel(&_firecall);
+	hrt_cancel(&_pollcall);
+
+	if (camera_trigger::g_camera_trigger != nullptr) {
+            delete (camera_trigger::g_camera_trigger);
+	}
+}
+
+void
+CameraTrigger::poll(void *arg)
+{
+
+	CameraTrigger *trig = reinterpret_cast<CameraTrigger *>(arg);
+
+	bool updated;
+	orb_check(trig->_vcommand_sub, &updated);
+	
+	if (updated) {
+		
+		orb_copy(ORB_ID(vehicle_command), trig->_vcommand_sub, &trig->_command);
+		
+		if(trig->_command.command == vehicle_command_s::VEHICLE_CMD_DO_TRIGGER_CONTROL)
+		{
+			if(trig->_command.param1 < 1)
+			{
+				if(trig->_trigger_enabled)
+				{
+					trig->_trigger_enabled = false ; 
+				}
+			}
+			else if(trig->_command.param1 >= 1)
+			{
+				if(!trig->_trigger_enabled)
+				{
+					trig->_trigger_enabled = true ;
+				} 
+			}
+
+			// Set trigger rate from command
+			if(trig->_command.param2 > 0)
+			{
+				trig->_integration_time = trig->_command.param2;
+				param_set(trig->integration_time, &(trig->_integration_time));
+			}		
+		}
+	}
+
+	if(!trig->_trigger_enabled)	{	
+		hrt_call_after(&trig->_pollcall, 1e6, (hrt_callout)&CameraTrigger::poll, trig); 
+		return;
+	}
+	else
+	{	
+		engage(trig);
+		hrt_call_after(&trig->_firecall, trig->_activation_time*1000, (hrt_callout)&CameraTrigger::disengage, trig);		
+		
+		orb_copy(ORB_ID(sensor_combined), trig->_sensor_sub, &trig->_sensor);
+					
+		trig->_trigger.timestamp = trig->_sensor.timestamp;	// get IMU timestamp
+		trig->_trigger.seq = trig->_trigger_seq++;
+
+		if (trig->_trigger_pub != nullptr) {
+			orb_publish(ORB_ID(camera_trigger), trig->_trigger_pub, &trig->_trigger);
+		} else {
+			trig->_trigger_pub = orb_advertise(ORB_ID(camera_trigger), &trig->_trigger);
+		}
+
+		hrt_call_after(&trig->_pollcall, (trig->_transfer_time + trig->_integration_time)*1000, (hrt_callout)&CameraTrigger::poll, trig); 
+	}
+	
+}
+
+void
+CameraTrigger::engage(void *arg)
+{
+
+	CameraTrigger *trig = reinterpret_cast<CameraTrigger *>(arg);
+
+	stm32_configgpio(GPIO_GPIO0_OUTPUT);
+	
+	if(trig->_polarity == 0)  	// ACTIVE_LOW 
+	{
+		stm32_gpiowrite(GPIO_GPIO0_OUTPUT, 0);			
+	}
+	else if(trig->_polarity == 1)	// ACTIVE_HIGH 
+	{
+		stm32_gpiowrite(GPIO_GPIO0_OUTPUT, 1);		
+	}
+	
+	
+}
+
+void
+CameraTrigger::disengage(void *arg)
+{
+
+	CameraTrigger *trig = reinterpret_cast<CameraTrigger *>(arg);
+		
+	stm32_configgpio(GPIO_GPIO0_OUTPUT);
+	
+	if(trig->_polarity == 0)  	// ACTIVE_LOW 
+	{
+		stm32_gpiowrite(GPIO_GPIO0_OUTPUT, 1);		
+	}
+	else if(trig->_polarity == 1)	// ACTIVE_HIGH 
+	{
+		stm32_gpiowrite(GPIO_GPIO0_OUTPUT, 0);			
+	}
+	
+}
+
+void
+CameraTrigger::info()
+{
+	warnx("Trigger state : %s", _trigger_enabled ? "enabled" : "disabled");
+	warnx("Trigger pin : %i", pin);
+	warnx("Trigger polarity : %s", _polarity ? "ACTIVE_HIGH" : "ACTIVE_LOW");
+	warnx("Shutter integration time : %.2f", (double)_integration_time);
+}
+
+static void usage()
+{
+	errx(1, "usage: camera_trigger {start|stop|info} [-p <n>]\n"
+		     "\t-p <n>\tUse specified AUX OUT pin number (default: 1)"
+		    );
+}
+
+int camera_trigger_main(int argc, char *argv[])
+{
+	if (argc < 2) {
+		usage();
+	}
+
+	if (!strcmp(argv[1], "start")) {
+
+		if (camera_trigger::g_camera_trigger != nullptr) {
+			errx(0, "already running");
+		}
+			
+		camera_trigger::g_camera_trigger = new CameraTrigger;
+
+		if (camera_trigger::g_camera_trigger == nullptr) {
+			errx(1, "alloc failed");
+		}
+		
+		if (argc > 3) {
+	
+			camera_trigger::g_camera_trigger->pin = (int)argv[3];
+			if (atoi(argv[3]) > 0 && atoi(argv[3]) < 6) {	
+				warnx("starting trigger on pin : %li ", atoi(argv[3]));	
+				camera_trigger::g_camera_trigger->pin = atoi(argv[3]);
+			}
+			else
+			{
+				usage(); 
+			}
+		}
+		camera_trigger::g_camera_trigger->start();
+
+		return 0;
+	}
+
+	if (camera_trigger::g_camera_trigger == nullptr) {
+		errx(1, "not running");
+	}
+
+	else if (!strcmp(argv[1], "stop")) {
+		camera_trigger::g_camera_trigger->stop(); 
+
+	}
+	else if (!strcmp(argv[1], "info")) {
+		camera_trigger::g_camera_trigger->info(); 
+
+	} else {
+		usage();
+	}
+
+	return 0;
+}
+

src/modules/camera_trigger/camera_trigger_params.c

@@ -0,0 +1,89 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 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 camera_trigger_params.c
+ * Camera trigger parameters
+ *
+ * @author Mohammed Kabir <mhkabir98@gmail.com>
+ */
+
+#include <nuttx/config.h>
+#include <systemlib/param/param.h>
+
+/**
+ * Camera trigger shutter integration time
+ *
+ * This parameter sets the time the shutter is open on the camera.
+ *
+ * @unit milliseconds
+ * @min 0.0
+ * @max 500.0
+ * @group Camera trigger
+ */
+PARAM_DEFINE_FLOAT(TRIG_INT_TIME, 300.0f);
+
+/**
+ * Camera trigger transfer time
+ *
+ * This parameter sets the time the image transfer takes (PointGrey mode_0)
+ *
+ * @unit milliseconds
+ * @min 15.0
+ * @max 33.0
+ * @group Camera trigger
+ */
+PARAM_DEFINE_FLOAT(TRIG_TRANS_TIME, 15.0f);
+
+/**
+ * Camera trigger polarity
+ *
+ * This parameter sets the polarity of the trigger (0 = ACTIVE_LOW, 1 = ACTIVE_HIGH )
+ *
+ * @min 0
+ * @max 1
+ * @group Camera trigger
+ */
+PARAM_DEFINE_INT32(TRIG_POLARITY, 0);
+
+/**
+ * Camera trigger activation time
+ *
+ * This parameter sets the time the trigger needs to pulled high or low to start light 
+ * integration.
+ *
+ * @unit milliseconds
+ * @default 4.0 ms
+ * @group Camera trigger
+ */
+PARAM_DEFINE_FLOAT(TRIG_ACT_TIME, 5.0f);

src/modules/camera_trigger/module.mk

@@ -0,0 +1,42 @@
+############################################################################
+#
+#   Copyright (C) 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.
+#
+############################################################################
+
+#
+# External camera-IMU synchronisation via GPIO
+#
+
+MODULE_COMMAND	= camera_trigger
+SRCS			= camera_trigger.cpp \
+			  camera_trigger_params.c
+
+MAXOPTIMIZATION	 = -Os

src/modules/commander/commander.cpp

@@ -784,6 +784,7 @@ bool handle_command(struct vehicle_status_s *status_local, const struct safety_s
 	case vehicle_command_s::VEHICLE_CMD_DO_MOUNT_CONTROL:
 	case vehicle_command_s::VEHICLE_CMD_DO_MOUNT_CONTROL_QUAT:
 	case vehicle_command_s::VEHICLE_CMD_DO_MOUNT_CONFIGURE:
+	case vehicle_command_s::VEHICLE_CMD_DO_TRIGGER_CONTROL:
 		/* ignore commands that handled in low prio loop */
 		break;
 

src/modules/mavlink/mavlink_main.cpp

@@ -1622,6 +1622,7 @@ Mavlink::task_main(int argc, char *argv[])
 		configure_stream("SYSTEM_TIME", 1.0f);
 		configure_stream("TIMESYNC", 10.0f);
 		configure_stream("ACTUATOR_CONTROL_TARGET0", 10.0f);
+		configure_stream("CAMERA_TRIGGER", 30.0f);
 		break;
 
 	case MAVLINK_MODE_OSD:

src/modules/mavlink/mavlink_messages.cpp

@@ -70,6 +70,7 @@
 #include <uORB/topics/battery_status.h>
 #include <uORB/topics/navigation_capabilities.h>
 #include <uORB/topics/distance_sensor.h>
+#include <uORB/topics/camera_trigger.h>
 #include <drivers/drv_rc_input.h>
 #include <drivers/drv_pwm_output.h>
 #include <systemlib/err.h>
@@ -1062,6 +1063,59 @@ protected:
 	}
 };
 
+
+class MavlinkStreamCameraTrigger : public MavlinkStream
+{
+public:
+	const char *get_name() const {
+		return MavlinkStreamCameraTrigger::get_name_static();
+	}
+
+	static const char *get_name_static() {
+		return "CAMERA_TRIGGER";
+	}
+
+	uint8_t get_id() {
+		return MAVLINK_MSG_ID_CAMERA_TRIGGER;
+	}
+
+	static MavlinkStream *new_instance(Mavlink *mavlink) {
+		return new MavlinkStreamCameraTrigger(mavlink);
+	}
+
+	unsigned get_size() {
+		return MAVLINK_MSG_ID_CAMERA_TRIGGER_LEN + MAVLINK_NUM_NON_PAYLOAD_BYTES;
+	}
+
+private:
+	MavlinkOrbSubscription *_camera_trigger_sub;
+	uint64_t _trig_time;
+
+	/* do not allow top copying this class */
+	MavlinkStreamCameraTrigger(MavlinkStreamCameraTrigger &);
+	MavlinkStreamCameraTrigger &operator = (const MavlinkStreamCameraTrigger &);
+
+protected:
+	explicit MavlinkStreamCameraTrigger(Mavlink *mavlink) : MavlinkStream(mavlink),
+	_camera_trigger_sub(_mavlink->add_orb_subscription(ORB_ID(camera_trigger))),
+	_trig_time(0)
+	{}
+
+	void send(const hrt_abstime t) {
+		struct camera_trigger_s trigger;
+
+		if (_camera_trigger_sub->update(&_trig_time, &trigger)) {
+			
+			mavlink_camera_trigger_t msg;
+
+			msg.time_usec = trigger.timestamp;
+			msg.seq = trigger.seq;
+			
+			_mavlink->send_message(MAVLINK_MSG_ID_CAMERA_TRIGGER, &msg);
+		}
+	}
+};
+
 class MavlinkStreamGlobalPositionInt : public MavlinkStream
 {
 public:

src/modules/uORB/objects_common.cpp

@@ -259,3 +259,6 @@ ORB_DEFINE(mc_att_ctrl_status, struct mc_att_ctrl_status_s);
 
 #include "topics/distance_sensor.h"
 ORB_DEFINE(distance_sensor, struct distance_sensor_s);
+
+#include "topics/camera_trigger.h"
+ORB_DEFINE(camera_trigger, struct camera_trigger_s);