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/**
* @file fw_pos_control_l1_params.c
*
* Parameters defined by the L1 position control task
*
* @author Lorenz Meier <lm@inf.ethz.ch>
*/
#include <nuttx/config.h>
#include <systemlib/param/param.h>
/*
* 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 to landing altitude)
*
* @unit meter
* @group L1 Control
*/
PARAM_DEFINE_FLOAT(FW_LND_FLALT, 8.0f);
/**
* Landing throttle limit altitude (relative landing altitude)
*
* Default of -1.0f lets the system default to applying throttle
* limiting at 2/3 of the flare altitude.
*
* @unit meter
* @group L1 Control
*/
PARAM_DEFINE_FLOAT(FW_LND_TLALT, -1.0f);
/**
* 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);
