/**************************************************************************** * * Copyright (c) 2013, 2014 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 fw_pos_control_l1_params.c * * Parameters defined by the L1 position control task * * @author Lorenz Meier */ #include #include /* * Controller parameters, accessible via MAVLink */ /** * L1 period * * This is the L1 distance and defines the tracking * point ahead of the aircraft its following. * A value of 25 meters works for most aircraft. Shorten * slowly during tuning until response is sharp without oscillation. * * @min 1.0 * @max 100.0 * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_L1_PERIOD, 25.0f); /** * L1 damping * * Damping factor for L1 control. * * @min 0.6 * @max 0.9 * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_L1_DAMPING, 0.75f); /** * Cruise throttle * * This is the throttle setting required to achieve the desired cruise speed. Most airframes have a value of 0.5-0.7. * * @min 0.0 * @max 1.0 * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_THR_CRUISE, 0.7f); /** * Throttle max slew rate * * Maximum slew rate for the commanded throttle * * @min 0.0 * @max 1.0 * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_THR_SLEW_MAX, 0.0f); /** * Negative pitch limit * * The minimum negative pitch the controller will output. * * @unit degrees * @min -60.0 * @max 0.0 * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_P_LIM_MIN, -45.0f); /** * Positive pitch limit * * The maximum positive pitch the controller will output. * * @unit degrees * @min 0.0 * @max 60.0 * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_P_LIM_MAX, 45.0f); /** * Controller roll limit * * The maximum roll the controller will output. * * @unit degrees * @min 0.0 * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_R_LIM, 45.0f); /** * Throttle limit max * * This is the maximum throttle % that can be used by the controller. * For overpowered aircraft, this should be reduced to a value that * provides sufficient thrust to climb at the maximum pitch angle PTCH_MAX. * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_THR_MAX, 1.0f); /** * Throttle limit min * * This is the minimum throttle % that can be used by the controller. * For electric aircraft this will normally be set to zero, but can be set * to a small non-zero value if a folding prop is fitted to prevent the * prop from folding and unfolding repeatedly in-flight or to provide * some aerodynamic drag from a turning prop to improve the descent rate. * * For aircraft with internal combustion engine this parameter should be set * for desired idle rpm. * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_THR_MIN, 0.0f); /** * Throttle limit value before flare * * This throttle value will be set as throttle limit at FW_LND_TLALT, * before arcraft will flare. * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_THR_LND_MAX, 1.0f); /** * Climbout Altitude difference * * If the altitude error exceeds this parameter, the system will climb out * with maximum throttle and minimum airspeed until it is closer than this * distance to the desired altitude. Mostly used for takeoff waypoints / modes. * Set to zero to disable climbout mode (not recommended). * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_CLMBOUT_DIFF, 25.0f); /** * Maximum climb rate * * This is the best climb rate that the aircraft can achieve with * the throttle set to THR_MAX and the airspeed set to the * default value. For electric aircraft make sure this number can be * achieved towards the end of flight when the battery voltage has reduced. * The setting of this parameter can be checked by commanding a positive * altitude change of 100m in loiter, RTL or guided mode. If the throttle * required to climb is close to THR_MAX and the aircraft is maintaining * airspeed, then this parameter is set correctly. If the airspeed starts * to reduce, then the parameter is set to high, and if the throttle * demand required to climb and maintain speed is noticeably less than * FW_THR_MAX, then either FW_T_CLMB_MAX should be increased or * FW_THR_MAX reduced. * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_T_CLMB_MAX, 5.0f); /** * Minimum descent rate * * This is the sink rate of the aircraft with the throttle * set to THR_MIN and flown at the same airspeed as used * to measure FW_T_CLMB_MAX. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_SINK_MIN, 2.0f); /** * Maximum descent rate * * This sets the maximum descent rate that the controller will use. * If this value is too large, the aircraft can over-speed on descent. * This should be set to a value that can be achieved without * exceeding the lower pitch angle limit and without over-speeding * the aircraft. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_SINK_MAX, 5.0f); /** * TECS time constant * * This is the time constant of the TECS control algorithm (in seconds). * Smaller values make it faster to respond, larger values make it slower * to respond. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_TIME_CONST, 5.0f); /** * TECS Throttle time constant * * This is the time constant of the TECS throttle control algorithm (in seconds). * Smaller values make it faster to respond, larger values make it slower * to respond. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_THRO_CONST, 8.0f); /** * Throttle damping factor * * This is the damping gain for the throttle demand loop. * Increase to add damping to correct for oscillations in speed and height. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_THR_DAMP, 0.5f); /** * Integrator gain * * This is the integrator gain on the control loop. * Increasing this gain increases the speed at which speed * and height offsets are trimmed out, but reduces damping and * increases overshoot. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_INTEG_GAIN, 0.1f); /** * Maximum vertical acceleration * * This is the maximum vertical acceleration (in metres/second square) * either up or down that the controller will use to correct speed * or height errors. The default value of 7 m/s/s (equivalent to +- 0.7 g) * allows for reasonably aggressive pitch changes if required to recover * from under-speed conditions. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_VERT_ACC, 7.0f); /** * Complementary filter "omega" parameter for height * * This is the cross-over frequency (in radians/second) of the complementary * filter used to fuse vertical acceleration and barometric height to obtain * an estimate of height rate and height. Increasing this frequency weights * the solution more towards use of the barometer, whilst reducing it weights * the solution more towards use of the accelerometer data. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_HGT_OMEGA, 3.0f); /** * Complementary filter "omega" parameter for speed * * This is the cross-over frequency (in radians/second) of the complementary * filter used to fuse longitudinal acceleration and airspeed to obtain an * improved airspeed estimate. Increasing this frequency weights the solution * more towards use of the arispeed sensor, whilst reducing it weights the * solution more towards use of the accelerometer data. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_SPD_OMEGA, 2.0f); /** * Roll -> Throttle feedforward * * Increasing this gain turn increases the amount of throttle that will * be used to compensate for the additional drag created by turning. * Ideally this should be set to approximately 10 x the extra sink rate * in m/s created by a 45 degree bank turn. Increase this gain if * the aircraft initially loses energy in turns and reduce if the * aircraft initially gains energy in turns. Efficient high aspect-ratio * aircraft (eg powered sailplanes) can use a lower value, whereas * inefficient low aspect-ratio models (eg delta wings) can use a higher value. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_RLL2THR, 10.0f); /** * Speed <--> Altitude priority * * This parameter adjusts the amount of weighting that the pitch control * applies to speed vs height errors. Setting it to 0.0 will cause the * pitch control to control height and ignore speed errors. This will * normally improve height accuracy but give larger airspeed errors. * Setting it to 2.0 will cause the pitch control loop to control speed * and ignore height errors. This will normally reduce airspeed errors, * but give larger height errors. The default value of 1.0 allows the pitch * control to simultaneously control height and speed. * Note to Glider Pilots - set this parameter to 2.0 (The glider will * adjust its pitch angle to maintain airspeed, ignoring changes in height). * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_SPDWEIGHT, 1.0f); /** * Pitch damping factor * * This is the damping gain for the pitch demand loop. Increase to add * damping to correct for oscillations in height. The default value of 0.0 * will work well provided the pitch to servo controller has been tuned * properly. * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_PTCH_DAMP, 0.0f); /** * Height rate P factor * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_HRATE_P, 0.05f); /** * Speed rate P factor * * @group Fixed Wing TECS */ PARAM_DEFINE_FLOAT(FW_T_SRATE_P, 0.05f); /** * Landing slope angle * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_LND_ANG, 5.0f); /** * * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_LND_HVIRT, 10.0f); /** * Landing flare altitude (relative) * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_LND_FLALT, 15.0f); /** * Landing throttle limit altitude (relative) * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_LND_TLALT, 5.0f); /** * Landing heading hold horizontal distance * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_LND_HHDIST, 15.0f); /** * Relative altitude threshold for range finder measurements for use during landing * * range finder measurements will only be used if the estimated relative altitude (gobal_pos.alt - landing_waypoint.alt) is < FW_LND_RFRALT * set to < 0 to disable * the correct value of this parameter depends on your range measuring device as well as on the terrain at the landing location * * @group L1 Control */ PARAM_DEFINE_FLOAT(FW_LND_RFRALT, -1.0f);