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authorAnton Babushkin <anton.babushkin@me.com>2013-05-17 12:23:48 +0400
committerAnton Babushkin <anton.babushkin@me.com>2013-05-17 12:23:48 +0400
commiteb2fc4e036e2a79228dd57e74de00828d5a4d950 (patch)
tree5cdcb80c0e1660928e5c72cf69fe81397d471dd6 /src/modules/multirotor_pos_control
parent861a21ef7559386d8301c6b8860a13ac2fc0ef64 (diff)
parentfa816d0fd65da461fd5bf8803cf00caebaf23c5c (diff)
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Merge branch 'master' into seatbelt_multirotor
Diffstat (limited to 'src/modules/multirotor_pos_control')
-rw-r--r--src/modules/multirotor_pos_control/module.mk41
-rw-r--r--src/modules/multirotor_pos_control/multirotor_pos_control.c325
-rw-r--r--src/modules/multirotor_pos_control/multirotor_pos_control_params.c73
-rw-r--r--src/modules/multirotor_pos_control/multirotor_pos_control_params.h72
-rw-r--r--src/modules/multirotor_pos_control/position_control.c235
-rw-r--r--src/modules/multirotor_pos_control/position_control.h50
6 files changed, 796 insertions, 0 deletions
diff --git a/src/modules/multirotor_pos_control/module.mk b/src/modules/multirotor_pos_control/module.mk
new file mode 100644
index 000000000..d04847745
--- /dev/null
+++ b/src/modules/multirotor_pos_control/module.mk
@@ -0,0 +1,41 @@
+############################################################################
+#
+# Copyright (c) 2012, 2013 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.
+#
+############################################################################
+
+#
+# Build multirotor position control
+#
+
+MODULE_COMMAND = multirotor_pos_control
+
+SRCS = multirotor_pos_control.c \
+ multirotor_pos_control_params.c
diff --git a/src/modules/multirotor_pos_control/multirotor_pos_control.c b/src/modules/multirotor_pos_control/multirotor_pos_control.c
new file mode 100644
index 000000000..6fe129d84
--- /dev/null
+++ b/src/modules/multirotor_pos_control/multirotor_pos_control.c
@@ -0,0 +1,325 @@
+/****************************************************************************
+ *
+ * Copyright (C) 2013 Anton Babushkin. All rights reserved.
+ * Author: Anton Babushkin <rk3dov@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 multirotor_pos_control.c
+ *
+ * Multirotor position controller
+ */
+
+#include <nuttx/config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <debug.h>
+#include <termios.h>
+#include <time.h>
+#include <sys/prctl.h>
+#include <drivers/drv_hrt.h>
+#include <uORB/uORB.h>
+#include <uORB/topics/parameter_update.h>
+#include <uORB/topics/vehicle_status.h>
+#include <uORB/topics/vehicle_attitude.h>
+#include <uORB/topics/manual_control_setpoint.h>
+#include <uORB/topics/vehicle_attitude_setpoint.h>
+#include <uORB/topics/vehicle_local_position.h>
+#include <uORB/topics/vehicle_local_position_setpoint.h>
+#include <uORB/topics/vehicle_vicon_position.h>
+#include <systemlib/systemlib.h>
+#include <mavlink/mavlink_log.h>
+
+#include "multirotor_pos_control_params.h"
+
+
+static bool thread_should_exit = false; /**< Deamon exit flag */
+static bool thread_running = false; /**< Deamon status flag */
+static int deamon_task; /**< Handle of deamon task / thread */
+
+__EXPORT int multirotor_pos_control_main(int argc, char *argv[]);
+
+/**
+ * Mainloop of position controller.
+ */
+static int multirotor_pos_control_thread_main(int argc, char *argv[]);
+
+/**
+ * Print the correct usage.
+ */
+static void usage(const char *reason);
+
+static void usage(const char *reason) {
+ if (reason)
+ fprintf(stderr, "%s\n", reason);
+ fprintf(stderr, "usage: deamon {start|stop|status} [-p <additional params>]\n\n");
+ exit(1);
+}
+
+/**
+ * The deamon app only briefly exists to start
+ * the background job. The stack size assigned in the
+ * Makefile does only apply to this management task.
+ *
+ * The actual stack size should be set in the call
+ * to task_spawn().
+ */
+int multirotor_pos_control_main(int argc, char *argv[]) {
+ if (argc < 1)
+ usage("missing command");
+
+ if (!strcmp(argv[1], "start")) {
+
+ if (thread_running) {
+ printf("multirotor_pos_control already running\n");
+ /* this is not an error */
+ exit(0);
+ }
+
+ thread_should_exit = false;
+ deamon_task = task_spawn("multirotor_pos_control",
+ SCHED_DEFAULT,
+ SCHED_PRIORITY_MAX - 60,
+ 4096,
+ multirotor_pos_control_thread_main,
+ (argv) ? (const char **)&argv[2] : (const char **)NULL);
+ exit(0);
+ }
+
+ if (!strcmp(argv[1], "stop")) {
+ thread_should_exit = true;
+ exit(0);
+ }
+
+ if (!strcmp(argv[1], "status")) {
+ if (thread_running) {
+ printf("\tmultirotor_pos_control app is running\n");
+ } else {
+ printf("\tmultirotor_pos_control app not started\n");
+ }
+ exit(0);
+ }
+
+ usage("unrecognized command");
+ exit(1);
+}
+
+static int multirotor_pos_control_thread_main(int argc, char *argv[]) {
+ /* welcome user */
+ printf("[multirotor_pos_control] started\n");
+ static int mavlink_fd;
+ mavlink_fd = open(MAVLINK_LOG_DEVICE, 0);
+ mavlink_log_info(mavlink_fd, "[multirotor_pos_control] started");
+
+ /* structures */
+ struct vehicle_status_s status;
+ memset(&status, 0, sizeof(status));
+ struct vehicle_attitude_s att;
+ memset(&att, 0, sizeof(att));
+ struct vehicle_attitude_setpoint_s att_sp;
+ memset(&att_sp, 0, sizeof(att_sp));
+ struct manual_control_setpoint_s manual;
+ memset(&manual, 0, sizeof(manual));
+ struct vehicle_local_position_s local_pos;
+ memset(&local_pos, 0, sizeof(local_pos));
+ struct vehicle_local_position_setpoint_s local_pos_sp;
+ memset(&local_pos_sp, 0, sizeof(local_pos_sp));
+
+ /* subscribe to attitude, motor setpoints and system state */
+ int param_sub = orb_subscribe(ORB_ID(parameter_update));
+ int state_sub = orb_subscribe(ORB_ID(vehicle_status));
+ int att_sub = orb_subscribe(ORB_ID(vehicle_attitude));
+ int att_sp_sub = orb_subscribe(ORB_ID(vehicle_attitude_setpoint));
+ int manual_sub = orb_subscribe(ORB_ID(manual_control_setpoint));
+ int local_pos_sp_sub = orb_subscribe(ORB_ID(vehicle_local_position_setpoint));
+ int local_pos_sub = orb_subscribe(ORB_ID(vehicle_local_position));
+
+ /* publish setpoint */
+ orb_advert_t local_pos_sp_pub = orb_advertise(ORB_ID(vehicle_local_position_setpoint), &local_pos_sp);
+ orb_advert_t att_sp_pub = orb_advertise(ORB_ID(vehicle_attitude_setpoint), &att_sp);
+
+ bool reset_sp_alt = true;
+ bool reset_sp_pos = true;
+ hrt_abstime t_prev = 0;
+ float alt_integral = 0.0f;
+ float alt_ctl_dz = 0.2f;
+
+ thread_running = true;
+
+ struct multirotor_position_control_params params;
+ struct multirotor_position_control_param_handles params_h;
+ parameters_init(&params_h);
+ parameters_update(&params_h, &params);
+
+ int paramcheck_counter = 0;
+
+ while (!thread_should_exit) {
+ orb_copy(ORB_ID(vehicle_status), state_sub, &status);
+
+ /* check parameters at 1 Hz*/
+ paramcheck_counter++;
+ if (paramcheck_counter == 50) {
+ bool param_updated;
+ orb_check(param_sub, &param_updated);
+ if (param_updated) {
+ parameters_update(&params_h, &params);
+ }
+ paramcheck_counter = 0;
+ }
+
+ /* Check if controller should act */
+ bool act = status.flag_system_armed && (
+ /* SAS modes */
+ (
+ status.flag_control_manual_enabled &&
+ status.manual_control_mode == VEHICLE_MANUAL_CONTROL_MODE_SAS && (
+ status.manual_sas_mode == VEHICLE_MANUAL_SAS_MODE_ALTITUDE ||
+ status.manual_sas_mode == VEHICLE_MANUAL_SAS_MODE_SIMPLE
+ )
+ ) ||
+ /* AUTO mode */
+ status.state_machine == SYSTEM_STATE_AUTO
+ );
+
+ hrt_abstime t = hrt_absolute_time();
+ float dt;
+ if (t_prev != 0) {
+ dt = (t - t_prev) * 0.000001f;
+ } else {
+ dt = 0.0f;
+ }
+ t_prev = t;
+ if (act) {
+ orb_copy(ORB_ID(manual_control_setpoint), manual_sub, &manual);
+ orb_copy(ORB_ID(vehicle_attitude), att_sub, &att);
+ orb_copy(ORB_ID(vehicle_attitude_setpoint), att_sp_sub, &att_sp);
+ orb_copy(ORB_ID(vehicle_local_position), local_pos_sub, &local_pos);
+ if (status.state_machine == SYSTEM_STATE_AUTO) {
+ orb_copy(ORB_ID(vehicle_local_position_setpoint), local_pos_sp_sub, &local_pos_sp);
+ }
+
+ if (reset_sp_alt) {
+ reset_sp_alt = false;
+ local_pos_sp.z = local_pos.z;
+ alt_integral = manual.throttle;
+ char str[80];
+ sprintf(str, "reset alt setpoint: z = %.2f, throttle = %.2f", local_pos_sp.z, manual.throttle);
+ mavlink_log_info(mavlink_fd, str);
+ }
+
+ if (status.manual_sas_mode == VEHICLE_MANUAL_SAS_MODE_SIMPLE && reset_sp_pos) {
+ reset_sp_pos = false;
+ local_pos_sp.x = local_pos.x;
+ local_pos_sp.y = local_pos.y;
+ char str[80];
+ sprintf(str, "reset pos setpoint: x = %.2f, y = %.2f", local_pos_sp.x, local_pos_sp.y);
+ mavlink_log_info(mavlink_fd, str);
+ }
+
+ float err_linear_limit = params.alt_d / params.alt_p * params.alt_rate_max;
+
+ if (status.flag_control_manual_enabled) {
+ /* move altitude setpoint with manual controls */
+ float alt_ctl = manual.throttle - 0.5f;
+ if (fabs(alt_ctl) < alt_ctl_dz) {
+ alt_ctl = 0.0f;
+ } else {
+ if (alt_ctl > 0.0f)
+ alt_ctl = (alt_ctl - alt_ctl_dz) / (0.5f - alt_ctl_dz);
+ else
+ alt_ctl = (alt_ctl + alt_ctl_dz) / (0.5f - alt_ctl_dz);
+ local_pos_sp.z -= alt_ctl * params.alt_rate_max * dt;
+ if (local_pos_sp.z > local_pos.z + err_linear_limit)
+ local_pos_sp.z = local_pos.z + err_linear_limit;
+ else if (local_pos_sp.z < local_pos.z - err_linear_limit)
+ local_pos_sp.z = local_pos.z - err_linear_limit;
+ }
+
+ if (status.manual_sas_mode == VEHICLE_MANUAL_SAS_MODE_SIMPLE) {
+ // TODO move position setpoint with manual controls
+ }
+ }
+
+ /* PID for altitude */
+ float alt_err = local_pos.z - local_pos_sp.z;
+ /* don't accelerate more than ALT_RATE_MAX, limit error to corresponding value */
+ if (alt_err > err_linear_limit) {
+ alt_err = err_linear_limit;
+ } else if (alt_err < -err_linear_limit) {
+ alt_err = -err_linear_limit;
+ }
+ /* P and D components */
+ float thrust_ctl_pd = alt_err * params.alt_p + local_pos.vz * params.alt_d;
+ /* add I component */
+ float thrust_ctl = thrust_ctl_pd + alt_integral;
+ alt_integral += thrust_ctl_pd / params.alt_p * params.alt_i * dt;
+ if (thrust_ctl < params.thr_min) {
+ thrust_ctl = params.thr_min;
+ } else if (thrust_ctl > params.thr_max) {
+ thrust_ctl = params.thr_max;
+ }
+ if (status.manual_sas_mode == VEHICLE_MANUAL_SAS_MODE_SIMPLE || status.state_machine == SYSTEM_STATE_AUTO) {
+ // TODO add position controller
+ } else {
+ reset_sp_pos = true;
+ }
+ att_sp.thrust = thrust_ctl;
+ att_sp.timestamp = hrt_absolute_time();
+ if (status.flag_control_manual_enabled) {
+ /* publish local position setpoint in manual mode */
+ orb_publish(ORB_ID(vehicle_local_position_setpoint), local_pos_sp_pub, &local_pos_sp);
+ }
+ /* publish new attitude setpoint */
+ orb_publish(ORB_ID(vehicle_attitude_setpoint), att_sp_pub, &att_sp);
+ } else {
+ reset_sp_alt = true;
+ reset_sp_pos = true;
+ }
+
+ /* run at approximately 50 Hz */
+ usleep(20000);
+
+ }
+
+ printf("[multirotor_pos_control] exiting\n");
+ mavlink_log_info(mavlink_fd, "[multirotor_pos_control] exiting");
+
+ thread_running = false;
+
+ fflush(stdout);
+ return 0;
+}
+
diff --git a/src/modules/multirotor_pos_control/multirotor_pos_control_params.c b/src/modules/multirotor_pos_control/multirotor_pos_control_params.c
new file mode 100644
index 000000000..90dd820f4
--- /dev/null
+++ b/src/modules/multirotor_pos_control/multirotor_pos_control_params.c
@@ -0,0 +1,73 @@
+/****************************************************************************
+ *
+ * Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ * Author: Tobias Naegeli <naegelit@student.ethz.ch>
+ * Lorenz Meier <lm@inf.ethz.ch>
+ *
+ * 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 multirotor_pos_control_params.c
+ *
+ * Parameters for multirotor_pos_control
+ */
+
+#include "multirotor_pos_control_params.h"
+
+/* controller parameters */
+PARAM_DEFINE_FLOAT(MPC_THR_MIN, 0.3f);
+PARAM_DEFINE_FLOAT(MPC_THR_MAX, 0.7f);
+PARAM_DEFINE_FLOAT(MPC_ALT_P, 0.1f);
+PARAM_DEFINE_FLOAT(MPC_ALT_I, 0.01f);
+PARAM_DEFINE_FLOAT(MPC_ALT_D, 0.2f);
+PARAM_DEFINE_FLOAT(MPC_ALT_RATE_MAX, 3.0f);
+
+int parameters_init(struct multirotor_position_control_param_handles *h)
+{
+ h->thr_min = param_find("MPC_THR_MIN");
+ h->thr_max = param_find("MPC_THR_MAX");
+ /* PID parameters */
+ h->alt_p = param_find("MPC_ALT_P");
+ h->alt_i = param_find("MPC_ALT_I");
+ h->alt_d = param_find("MPC_ALT_D");
+ h->alt_rate_max = param_find("MPC_ALT_RATE_MAX");
+ return OK;
+}
+
+int parameters_update(const struct multirotor_position_control_param_handles *h, struct multirotor_position_control_params *p)
+{
+ param_get(h->thr_min, &(p->thr_min));
+ param_get(h->thr_max, &(p->thr_max));
+ param_get(h->alt_p, &(p->alt_p));
+ param_get(h->alt_i, &(p->alt_i));
+ param_get(h->alt_d, &(p->alt_d));
+ param_get(h->alt_rate_max, &(p->alt_rate_max));
+ return OK;
+}
diff --git a/src/modules/multirotor_pos_control/multirotor_pos_control_params.h b/src/modules/multirotor_pos_control/multirotor_pos_control_params.h
new file mode 100644
index 000000000..849055cd1
--- /dev/null
+++ b/src/modules/multirotor_pos_control/multirotor_pos_control_params.h
@@ -0,0 +1,72 @@
+/****************************************************************************
+ *
+ * Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ * Author: Tobias Naegeli <naegelit@student.ethz.ch>
+ * Lorenz Meier <lm@inf.ethz.ch>
+ *
+ * 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 multirotor_position_control_params.h
+ *
+ * Parameters for position controller
+ */
+
+#include <systemlib/param/param.h>
+
+struct multirotor_position_control_params {
+ float thr_min;
+ float thr_max;
+ float alt_p;
+ float alt_i;
+ float alt_d;
+ float alt_rate_max;
+};
+
+struct multirotor_position_control_param_handles {
+ param_t thr_min;
+ param_t thr_max;
+ param_t alt_p;
+ param_t alt_i;
+ param_t alt_d;
+ param_t alt_rate_max;
+};
+
+/**
+ * Initialize all parameter handles and values
+ *
+ */
+int parameters_init(struct multirotor_position_control_param_handles *h);
+
+/**
+ * Update all parameters
+ *
+ */
+int parameters_update(const struct multirotor_position_control_param_handles *h, struct multirotor_position_control_params *p);
diff --git a/src/modules/multirotor_pos_control/position_control.c b/src/modules/multirotor_pos_control/position_control.c
new file mode 100644
index 000000000..9c53a5bf6
--- /dev/null
+++ b/src/modules/multirotor_pos_control/position_control.c
@@ -0,0 +1,235 @@
+// /****************************************************************************
+// *
+// * Copyright (C) 2008-2012 PX4 Development Team. All rights reserved.
+// * Author: @author Lorenz Meier <lm@inf.ethz.ch>
+// * @author Laurens Mackay <mackayl@student.ethz.ch>
+// * @author Tobias Naegeli <naegelit@student.ethz.ch>
+// * @author Martin Rutschmann <rutmarti@student.ethz.ch>
+// *
+// * 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 multirotor_position_control.c
+// * Implementation of the position control for a multirotor VTOL
+// */
+
+// #include <stdio.h>
+// #include <stdlib.h>
+// #include <stdio.h>
+// #include <stdint.h>
+// #include <math.h>
+// #include <stdbool.h>
+// #include <float.h>
+// #include <systemlib/pid/pid.h>
+
+// #include "multirotor_position_control.h"
+
+// void control_multirotor_position(const struct vehicle_state_s *vstatus, const struct vehicle_manual_control_s *manual,
+// const struct vehicle_attitude_s *att, const struct vehicle_local_position_s *local_pos,
+// const struct vehicle_local_position_setpoint_s *local_pos_sp, struct vehicle_attitude_setpoint_s *att_sp)
+// {
+// static PID_t distance_controller;
+
+// static int read_ret;
+// static global_data_position_t position_estimated;
+
+// static uint16_t counter;
+
+// static bool initialized;
+// static uint16_t pm_counter;
+
+// static float lat_next;
+// static float lon_next;
+
+// static float pitch_current;
+
+// static float thrust_total;
+
+
+// if (initialized == false) {
+
+// pid_init(&distance_controller,
+// global_data_parameter_storage->pm.param_values[PARAM_PID_POS_P],
+// global_data_parameter_storage->pm.param_values[PARAM_PID_POS_I],
+// global_data_parameter_storage->pm.param_values[PARAM_PID_POS_D],
+// global_data_parameter_storage->pm.param_values[PARAM_PID_POS_AWU],
+// PID_MODE_DERIVATIV_CALC, 150);//150
+
+// // pid_pos_lim = global_data_parameter_storage->pm.param_values[PARAM_PID_POS_LIM];
+// // pid_pos_z_lim = global_data_parameter_storage->pm.param_values[PARAM_PID_POS_Z_LIM];
+
+// thrust_total = 0.0f;
+
+// /* Position initialization */
+// /* Wait for new position estimate */
+// do {
+// read_ret = read_lock_position(&position_estimated);
+// } while (read_ret != 0);
+
+// lat_next = position_estimated.lat;
+// lon_next = position_estimated.lon;
+
+// /* attitude initialization */
+// global_data_lock(&global_data_attitude->access_conf);
+// pitch_current = global_data_attitude->pitch;
+// global_data_unlock(&global_data_attitude->access_conf);
+
+// initialized = true;
+// }
+
+// /* load new parameters with 10Hz */
+// if (counter % 50 == 0) {
+// if (global_data_trylock(&global_data_parameter_storage->access_conf) == 0) {
+// /* check whether new parameters are available */
+// if (global_data_parameter_storage->counter > pm_counter) {
+// pid_set_parameters(&distance_controller,
+// global_data_parameter_storage->pm.param_values[PARAM_PID_POS_P],
+// global_data_parameter_storage->pm.param_values[PARAM_PID_POS_I],
+// global_data_parameter_storage->pm.param_values[PARAM_PID_POS_D],
+// global_data_parameter_storage->pm.param_values[PARAM_PID_POS_AWU]);
+
+// //
+// // pid_pos_lim = global_data_parameter_storage->pm.param_values[PARAM_PID_POS_LIM];
+// // pid_pos_z_lim = global_data_parameter_storage->pm.param_values[PARAM_PID_POS_Z_LIM];
+
+// pm_counter = global_data_parameter_storage->counter;
+// printf("Position controller changed pid parameters\n");
+// }
+// }
+
+// global_data_unlock(&global_data_parameter_storage->access_conf);
+// }
+
+
+// /* Wait for new position estimate */
+// do {
+// read_ret = read_lock_position(&position_estimated);
+// } while (read_ret != 0);
+
+// /* Get next waypoint */ //TODO: add local copy
+
+// if (0 == global_data_trylock(&global_data_position_setpoint->access_conf)) {
+// lat_next = global_data_position_setpoint->x;
+// lon_next = global_data_position_setpoint->y;
+// global_data_unlock(&global_data_position_setpoint->access_conf);
+// }
+
+// /* Get distance to waypoint */
+// float distance_to_waypoint = get_distance_to_next_waypoint(position_estimated.lat , position_estimated.lon, lat_next, lon_next);
+// // if(counter % 5 == 0)
+// // printf("distance_to_waypoint: %.4f\n", distance_to_waypoint);
+
+// /* Get bearing to waypoint (direction on earth surface to next waypoint) */
+// float bearing = get_bearing_to_next_waypoint(position_estimated.lat, position_estimated.lon, lat_next, lon_next);
+
+// if (counter % 5 == 0)
+// printf("bearing: %.4f\n", bearing);
+
+// /* Calculate speed in direction of bearing (needed for controller) */
+// float speed_norm = sqrtf(position_estimated.vx * position_estimated.vx + position_estimated.vy * position_estimated.vy);
+// // if(counter % 5 == 0)
+// // printf("speed_norm: %.4f\n", speed_norm);
+// float speed_to_waypoint = 0; //(position_estimated.vx * cosf(bearing) + position_estimated.vy * sinf(bearing))/speed_norm; //FIXME, TODO: re-enable this once we have a full estimate of the speed, then we can do a PID for the distance controller
+
+// /* Control Thrust in bearing direction */
+// float horizontal_thrust = -pid_calculate(&distance_controller, 0, distance_to_waypoint, speed_to_waypoint,
+// CONTROL_PID_POSITION_INTERVAL); //TODO: maybe this "-" sign is an error somewhere else
+
+// // if(counter % 5 == 0)
+// // printf("horizontal thrust: %.4f\n", horizontal_thrust);
+
+// /* Get total thrust (from remote for now) */
+// if (0 == global_data_trylock(&global_data_rc_channels->access_conf)) {
+// thrust_total = (float)global_data_rc_channels->chan[THROTTLE].scale; //TODO: how should we use the RC_CHANNELS_FUNCTION enum?
+// global_data_unlock(&global_data_rc_channels->access_conf);
+// }
+
+// const float max_gas = 500.0f;
+// thrust_total *= max_gas / 20000.0f; //TODO: check this
+// thrust_total += max_gas / 2.0f;
+
+
+// if (horizontal_thrust > thrust_total) {
+// horizontal_thrust = thrust_total;
+
+// } else if (horizontal_thrust < -thrust_total) {
+// horizontal_thrust = -thrust_total;
+// }
+
+
+
+// //TODO: maybe we want to add a speed controller later...
+
+// /* Calclulate thrust in east and north direction */
+// float thrust_north = cosf(bearing) * horizontal_thrust;
+// float thrust_east = sinf(bearing) * horizontal_thrust;
+
+// if (counter % 10 == 0) {
+// printf("thrust north: %.4f\n", thrust_north);
+// printf("thrust east: %.4f\n", thrust_east);
+// fflush(stdout);
+// }
+
+// /* Get current attitude */
+// if (0 == global_data_trylock(&global_data_attitude->access_conf)) {
+// pitch_current = global_data_attitude->pitch;
+// global_data_unlock(&global_data_attitude->access_conf);
+// }
+
+// /* Get desired pitch & roll */
+// float pitch_desired = 0.0f;
+// float roll_desired = 0.0f;
+
+// if (thrust_total != 0) {
+// float pitch_fraction = -thrust_north / thrust_total;
+// float roll_fraction = thrust_east / (cosf(pitch_current) * thrust_total);
+
+// if (roll_fraction < -1) {
+// roll_fraction = -1;
+
+// } else if (roll_fraction > 1) {
+// roll_fraction = 1;
+// }
+
+// // if(counter % 5 == 0)
+// // {
+// // printf("pitch_fraction: %.4f, roll_fraction: %.4f\n",pitch_fraction, roll_fraction);
+// // fflush(stdout);
+// // }
+
+// pitch_desired = asinf(pitch_fraction);
+// roll_desired = asinf(roll_fraction);
+// }
+
+// att_sp.roll = roll_desired;
+// att_sp.pitch = pitch_desired;
+
+// counter++;
+// }
diff --git a/src/modules/multirotor_pos_control/position_control.h b/src/modules/multirotor_pos_control/position_control.h
new file mode 100644
index 000000000..2144ebc34
--- /dev/null
+++ b/src/modules/multirotor_pos_control/position_control.h
@@ -0,0 +1,50 @@
+/****************************************************************************
+ *
+ * Copyright (C) 2008-2012 PX4 Development Team. All rights reserved.
+ * Author: @author Lorenz Meier <lm@inf.ethz.ch>
+ * @author Laurens Mackay <mackayl@student.ethz.ch>
+ * @author Tobias Naegeli <naegelit@student.ethz.ch>
+ * @author Martin Rutschmann <rutmarti@student.ethz.ch>
+ *
+ * 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 multirotor_position_control.h
+ * Definition of the position control for a multirotor VTOL
+ */
+
+// #ifndef POSITION_CONTROL_H_
+// #define POSITION_CONTROL_H_
+
+// void control_multirotor_position(const struct vehicle_state_s *vstatus, const struct vehicle_manual_control_s *manual,
+// const struct vehicle_attitude_s *att, const struct vehicle_local_position_s *local_pos,
+// const struct vehicle_local_position_setpoint_s *local_pos_sp, struct vehicle_attitude_setpoint_s *att_sp);
+
+// #endif /* POSITION_CONTROL_H_ */