Commit 4e71b197 authored by Lorenz Meier's avatar Lorenz Meier
Browse files

Add mag declination to SITL gazebo

parent 6867478b
......@@ -77,7 +77,7 @@ add_library(gazebo_lidar_plugin SHARED src/gazebo_lidar_plugin.cpp)
target_link_libraries(gazebo_lidar_plugin mav_msgs ${Boost_LIBRARIES} ${GAZEBO_LIBRARIES} ${SDF_LIBRARIES} ${Boost_SYSTEM_LIBRARY_RELEASE} ${Boost_THREAD_LIBRARY_RELEASE})
add_dependencies(gazebo_lidar_plugin mav_msgs)
add_library(rotors_gazebo_mavlink_interface SHARED src/gazebo_mavlink_interface.cpp)
add_library(rotors_gazebo_mavlink_interface SHARED src/gazebo_mavlink_interface.cpp src/geo_mag_declination.cpp)
target_link_libraries(rotors_gazebo_mavlink_interface mav_msgs ${Boost_LIBRARIES} ${GAZEBO_LIBRARIES} ${SDF_LIBRARIES} ${Boost_SYSTEM_LIBRARY_RELEASE} ${Boost_THREAD_LIBRARY_RELEASE})
add_dependencies(rotors_gazebo_mavlink_interface mav_msgs)
......
......@@ -95,6 +95,9 @@ class GazeboMavlinkInterface : public ModelPlugin {
opticalFlow_sub_topic_(kDefaultOpticalFlowTopic),
lidar_sub_topic_(kDefaultLidarTopic),
mavlink_control_sub_topic_(kDefaultMavlinkControlSubTopic) {}
lat_rad(0.0),
lon_rad(0.0)
{}
~GazeboMavlinkInterface();
void Publish();
......@@ -161,6 +164,8 @@ class GazeboMavlinkInterface : public ModelPlugin {
common::Time last_time_;
common::Time last_gps_time_;
double gps_update_interval_;
double lat_rad;
double lon_rad;
math::Vector3 gravity_W_;
math::Vector3 velocity_prev_W_;
......
/****************************************************************************
*
* Copyright (c) 2014 MAV GEO Library (MAVGEO). 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 MAVGEO 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 geo_mag_declination.h
*
* Calculation / lookup table for earth magnetic field declination.
*
*/
#pragma once
__BEGIN_DECLS
float get_mag_declination(float lat, float lon);
__END_DECLS
......@@ -20,6 +20,7 @@
#include "gazebo_mavlink_interface.h"
#include "geo_mag_declination.h"
#define UDP_PORT 14560
#define UDP_PORT_2 14556
......@@ -197,8 +198,6 @@ void GazeboMavlinkInterface::OnUpdate(const common::UpdateInfo& /*_info*/) {
double c = sqrt(x_rad * x_rad + y_rad * y_rad);
double sin_c = sin(c);
double cos_c = cos(c);
double lat_rad;
double lon_rad;
if (c != 0.0) {
lat_rad = asin(cos_c * sin(lat_zurich) + (x_rad * sin_c * cos(lat_zurich)) / c);
lon_rad = (lon_zurich + atan2(y_rad * sin_c, c * cos(lat_zurich) * cos_c - x_rad * sin(lat_zurich) * sin_c));
......@@ -333,6 +332,14 @@ void GazeboMavlinkInterface::ImuCallback(ImuPtr& imu_message) {
C_W_I.y = imu_message->orientation().y();
C_W_I.z = imu_message->orientation().z();
float declination = get_mag_declination(lat_rad, lon_rad);
math::Quaternion C_D_I(0.0, 0.0, declination);
math::Vector3 mag_decl = C_D_I.RotateVectorReverse(mag_W_);
// TODO replace mag_W_ in the line below with mag_decl
math::Vector3 mag_I = C_W_I.RotateVectorReverse(mag_W_); // TODO: Add noise based on bais and variance like for imu and gyro
math::Vector3 body_vel = C_W_I.RotateVectorReverse(model_->GetWorldLinearVel());
......
/****************************************************************************
*
* Copyright (c) 2014 MAV GEO Library (MAVGEO). 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 MAVGEO 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 geo_mag_declination.c
*
* Calculation / lookup table for earth magnetic field declination.
*
* Lookup table from Scott Ferguson <scottfromscott@gmail.com>
*
* XXX Lookup table currently too coarse in resolution (only full degrees)
* and lat/lon res - needs extension medium term.
*
*/
#include <stdint.h>
#include "geo_mag_declination.h"
/** set this always to the sampling in degrees for the table below */
#define SAMPLING_RES 10.0f
#define SAMPLING_MIN_LAT -60.0f
#define SAMPLING_MAX_LAT 60.0f
#define SAMPLING_MIN_LON -180.0f
#define SAMPLING_MAX_LON 180.0f
static const int8_t declination_table[13][37] = \
{
{ 46, 45, 44, 42, 41, 40, 38, 36, 33, 28, 23, 16, 10, 4, -1, -5, -9, -14, -19, -26, -33, -40, -48, -55, -61, -66, -71, -74, -75, -72, -61, -25, 22, 40, 45, 47, 46 },
{ 30, 30, 30, 30, 29, 29, 29, 29, 27, 24, 18, 11, 3, -3, -9, -12, -15, -17, -21, -26, -32, -39, -45, -51, -55, -57, -56, -53, -44, -31, -14, 0, 13, 21, 26, 29, 30 },
{ 21, 22, 22, 22, 22, 22, 22, 22, 21, 18, 13, 5, -3, -11, -17, -20, -21, -22, -23, -25, -29, -35, -40, -44, -45, -44, -40, -32, -22, -12, -3, 3, 9, 14, 18, 20, 21 },
{ 16, 17, 17, 17, 17, 17, 16, 16, 16, 13, 8, 0, -9, -16, -21, -24, -25, -25, -23, -20, -21, -24, -28, -31, -31, -29, -24, -17, -9, -3, 0, 4, 7, 10, 13, 15, 16 },
{ 12, 13, 13, 13, 13, 13, 12, 12, 11, 9, 3, -4, -12, -19, -23, -24, -24, -22, -17, -12, -9, -10, -13, -17, -18, -16, -13, -8, -3, 0, 1, 3, 6, 8, 10, 12, 12 },
{ 10, 10, 10, 10, 10, 10, 10, 9, 9, 6, 0, -6, -14, -20, -22, -22, -19, -15, -10, -6, -2, -2, -4, -7, -8, -8, -7, -4, 0, 1, 1, 2, 4, 6, 8, 10, 10 },
{ 9, 9, 9, 9, 9, 9, 8, 8, 7, 4, -1, -8, -15, -19, -20, -18, -14, -9, -5, -2, 0, 1, 0, -2, -3, -4, -3, -2, 0, 0, 0, 1, 3, 5, 7, 8, 9 },
{ 8, 8, 8, 9, 9, 9, 8, 8, 6, 2, -3, -9, -15, -18, -17, -14, -10, -6, -2, 0, 1, 2, 2, 0, -1, -1, -2, -1, 0, 0, 0, 0, 1, 3, 5, 7, 8 },
{ 8, 9, 9, 10, 10, 10, 10, 8, 5, 0, -5, -11, -15, -16, -15, -12, -8, -4, -1, 0, 2, 3, 2, 1, 0, 0, 0, 0, 0, -1, -2, -2, -1, 0, 3, 6, 8 },
{ 6, 9, 10, 11, 12, 12, 11, 9, 5, 0, -7, -12, -15, -15, -13, -10, -7, -3, 0, 1, 2, 3, 3, 3, 2, 1, 0, 0, -1, -3, -4, -5, -5, -2, 0, 3, 6 },
{ 5, 8, 11, 13, 15, 15, 14, 11, 5, -1, -9, -14, -17, -16, -14, -11, -7, -3, 0, 1, 3, 4, 5, 5, 5, 4, 3, 1, -1, -4, -7, -8, -8, -6, -2, 1, 5 },
{ 4, 8, 12, 15, 17, 18, 16, 12, 5, -3, -12, -18, -20, -19, -16, -13, -8, -4, -1, 1, 4, 6, 8, 9, 9, 9, 7, 3, -1, -6, -10, -12, -11, -9, -5, 0, 4 },
{ 3, 9, 14, 17, 20, 21, 19, 14, 4, -8, -19, -25, -26, -25, -21, -17, -12, -7, -2, 1, 5, 9, 13, 15, 16, 16, 13, 7, 0, -7, -12, -15, -14, -11, -6, -1, 3 },
};
static float get_lookup_table_val(unsigned lat, unsigned lon);
float get_mag_declination(float lat, float lon)
{
/*
* If the values exceed valid ranges, return zero as default
* as we have no way of knowing what the closest real value
* would be.
*/
if (lat < -90.0f || lat > 90.0f ||
lon < -180.0f || lon > 180.0f) {
return 0.0f;
}
/* round down to nearest sampling resolution */
int min_lat = (int)(lat / SAMPLING_RES) * SAMPLING_RES;
int min_lon = (int)(lon / SAMPLING_RES) * SAMPLING_RES;
/* for the rare case of hitting the bounds exactly
* the rounding logic wouldn't fit, so enforce it.
*/
/* limit to table bounds - required for maxima even when table spans full globe range */
if (lat <= SAMPLING_MIN_LAT) {
min_lat = SAMPLING_MIN_LAT;
}
if (lat >= SAMPLING_MAX_LAT) {
min_lat = (int)(lat / SAMPLING_RES) * SAMPLING_RES - SAMPLING_RES;
}
if (lon <= SAMPLING_MIN_LON) {
min_lon = SAMPLING_MIN_LON;
}
if (lon >= SAMPLING_MAX_LON) {
min_lon = (int)(lon / SAMPLING_RES) * SAMPLING_RES - SAMPLING_RES;
}
/* find index of nearest low sampling point */
unsigned min_lat_index = (-(SAMPLING_MIN_LAT) + min_lat) / SAMPLING_RES;
unsigned min_lon_index = (-(SAMPLING_MIN_LON) + min_lon) / SAMPLING_RES;
float declination_sw = get_lookup_table_val(min_lat_index, min_lon_index);
float declination_se = get_lookup_table_val(min_lat_index, min_lon_index + 1);
float declination_ne = get_lookup_table_val(min_lat_index + 1, min_lon_index + 1);
float declination_nw = get_lookup_table_val(min_lat_index + 1, min_lon_index);
/* perform bilinear interpolation on the four grid corners */
float declination_min = ((lon - min_lon) / SAMPLING_RES) * (declination_se - declination_sw) + declination_sw;
float declination_max = ((lon - min_lon) / SAMPLING_RES) * (declination_ne - declination_nw) + declination_nw;
return ((lat - min_lat) / SAMPLING_RES) * (declination_max - declination_min) + declination_min;
}
float get_lookup_table_val(unsigned lat_index, unsigned lon_index)
{
return declination_table[lat_index][lon_index];
}
\ No newline at end of file
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