diff options
Diffstat (limited to 'src/modules/fw_pos_control_l1/landingslope.cpp')
| -rw-r--r-- | src/modules/fw_pos_control_l1/landingslope.cpp | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/src/modules/fw_pos_control_l1/landingslope.cpp b/src/modules/fw_pos_control_l1/landingslope.cpp new file mode 100644 index 000000000..42e00da05 --- /dev/null +++ b/src/modules/fw_pos_control_l1/landingslope.cpp @@ -0,0 +1,114 @@ +/**************************************************************************** + * + * Copyright (C) 2008-2012 PX4 Development Team. All rights reserved. + * Author: @author Thomas Gubler <thomasgubler@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: landingslope.cpp + * + */ + +#include "landingslope.h" + +#include <nuttx/config.h> +#include <stdlib.h> +#include <errno.h> +#include <math.h> +#include <unistd.h> +#include <mathlib/mathlib.h> + +void Landingslope::update(float landing_slope_angle_rad_new, + float flare_relative_alt_new, + float motor_lim_relative_alt_new, + float H1_virt_new) +{ + + _landing_slope_angle_rad = landing_slope_angle_rad_new; + _flare_relative_alt = flare_relative_alt_new; + _motor_lim_relative_alt = motor_lim_relative_alt_new; + _H1_virt = H1_virt_new; + + calculateSlopeValues(); +} + +void Landingslope::calculateSlopeValues() +{ + _H0 = _flare_relative_alt + _H1_virt; + _d1 = _flare_relative_alt/tanf(_landing_slope_angle_rad); + _flare_constant = (_H0 * _d1)/_flare_relative_alt; + _flare_length = - logf(_H1_virt/_H0) * _flare_constant; + _horizontal_slope_displacement = (_flare_length - _d1); +} + +float Landingslope::getLandingSlopeRelativeAltitude(float wp_landing_distance) +{ + return Landingslope::getLandingSlopeRelativeAltitude(wp_landing_distance, _horizontal_slope_displacement, _landing_slope_angle_rad); +} + +float Landingslope::getLandingSlopeRelativeAltitudeSave(float wp_landing_distance, float bearing_lastwp_currwp, float bearing_airplane_currwp) +{ + /* If airplane is in front of waypoint return slope altitude, else return waypoint altitude */ + if (fabsf(bearing_airplane_currwp - bearing_lastwp_currwp) < math::radians(90.0f)) + return getLandingSlopeRelativeAltitude(wp_landing_distance); + else + return 0.0f; +} + +float Landingslope::getLandingSlopeAbsoluteAltitude(float wp_landing_distance, float wp_altitude) +{ + return Landingslope::getLandingSlopeAbsoluteAltitude(wp_landing_distance, wp_altitude, _horizontal_slope_displacement, _landing_slope_angle_rad); +} + +float Landingslope::getLandingSlopeAbsoluteAltitudeSave(float wp_landing_distance, float bearing_lastwp_currwp, float bearing_airplane_currwp, float wp_altitude) +{ + /* If airplane is in front of waypoint return slope altitude, else return waypoint altitude */ + if (fabsf(bearing_airplane_currwp - bearing_lastwp_currwp) < math::radians(90.0f)) + return getLandingSlopeAbsoluteAltitude(wp_landing_distance, wp_altitude); + else + return wp_altitude; +} + +float Landingslope::getFlareCurveRelativeAltitudeSave(float wp_landing_distance, float bearing_lastwp_currwp, float bearing_airplane_currwp) +{ + /* If airplane is in front of waypoint return flare curve altitude, else return waypoint altitude */ + if (fabsf(bearing_airplane_currwp - bearing_lastwp_currwp) < math::radians(90.0f)) + return _H0 * expf(-math::max(0.0f, _flare_length - wp_landing_distance)/_flare_constant) - _H1_virt; + else + return 0.0f; +} + +float Landingslope::getFlareCurveAbsoluteAltitudeSave(float wp_landing_distance, float bearing_lastwp_currwp, float bearing_airplane_currwp, float wp_landing_altitude) +{ + + return wp_landing_altitude + getFlareCurveRelativeAltitudeSave(wp_landing_distance, bearing_lastwp_currwp, bearing_airplane_currwp); +} + |