From 9e56652d3eda75a2738bcb9eab3ff99ac2aa455b Mon Sep 17 00:00:00 2001 From: Highlander-UA <315u448@ukrpost.net> Date: Sat, 15 Feb 2014 13:34:49 +0200 Subject: [PATCH] Added comments for L1 control parameters --- .../fw_pos_control_l1_params.c | 193 +++++++++++++++++- 1 file changed, 186 insertions(+), 7 deletions(-) diff --git a/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c b/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c index 512ca7b8ac..9f15a93866 100644 --- a/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c +++ b/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c @@ -120,57 +120,236 @@ PARAM_DEFINE_FLOAT(FW_P_LIM_MIN, -45.0f); 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); - -PARAM_DEFINE_FLOAT(FW_THR_MIN, 0.0f); - - +/* + * 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. + * +*/ 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. +*/ +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. +*/ PARAM_DEFINE_FLOAT(FW_THR_LND_MAX, 1.0f); + +/* + * 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. +*/ 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. +*/ 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. +*/ +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. +*/ PARAM_DEFINE_FLOAT(FW_T_TIME_CONST, 5.0f); +/* + * 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. +*/ 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. +*/ PARAM_DEFINE_FLOAT(FW_T_INTEG_GAIN, 0.1f); +/* + * Maximum vertical acceleration + * + * This is the maximum vertical acceleration (in metres/second^2) + * 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. +*/ 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. + +*/ 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. +*/ 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. +*/ 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). +*/ 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. +*/ PARAM_DEFINE_FLOAT(FW_T_PTCH_DAMP, 0.0f); - -PARAM_DEFINE_FLOAT(FW_T_SINK_MAX, 5.0f); - +/* + * Height rate P factor +*/ PARAM_DEFINE_FLOAT(FW_T_HRATE_P, 0.05f); + +/* + * Speed rate P factor +*/ PARAM_DEFINE_FLOAT(FW_T_SRATE_P, 0.05f); +/* + * Landing slope angle +*/ PARAM_DEFINE_FLOAT(FW_LND_ANG, 5.0f); + +/* + * Landing slope length +*/ PARAM_DEFINE_FLOAT(FW_LND_SLLR, 0.9f); + +/* + * +*/ PARAM_DEFINE_FLOAT(FW_LND_HVIRT, 10.0f); + +/* + * Landing flare altitude (relative) +*/ PARAM_DEFINE_FLOAT(FW_LND_FLALT, 15.0f); + +/* + * Landing throttle limit altitude (relative) +*/ PARAM_DEFINE_FLOAT(FW_LND_TLALT, 5.0f); + +/* + * Landing heading hold horizontal distance +*/ PARAM_DEFINE_FLOAT(FW_LND_HHDIST, 15.0f);