mirror of https://github.com/ArduPilot/ardupilot
337 lines
11 KiB
C++
337 lines
11 KiB
C++
/*
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
// Code by Jon Challinger
|
|
// Modified by Paul Riseborough
|
|
//
|
|
|
|
#include <AP_HAL/AP_HAL.h>
|
|
#include "AP_RollController.h"
|
|
#include <AP_AHRS/AP_AHRS.h>
|
|
#include <AP_Scheduler/AP_Scheduler.h>
|
|
#include <GCS_MAVLink/GCS.h>
|
|
|
|
extern const AP_HAL::HAL& hal;
|
|
|
|
const AP_Param::GroupInfo AP_RollController::var_info[] = {
|
|
// @Param: 2SRV_TCONST
|
|
// @DisplayName: Roll Time Constant
|
|
// @Description: Time constant in seconds from demanded to achieved roll angle. Most models respond well to 0.5. May be reduced for faster responses, but setting lower than a model can achieve will not help.
|
|
// @Range: 0.4 1.0
|
|
// @Units: s
|
|
// @Increment: 0.1
|
|
// @User: Advanced
|
|
AP_GROUPINFO("2SRV_TCONST", 0, AP_RollController, gains.tau, 0.5f),
|
|
|
|
// index 1 to 3 reserved for old PID values
|
|
|
|
// @Param: 2SRV_RMAX
|
|
// @DisplayName: Maximum Roll Rate
|
|
// @Description: This sets the maximum roll rate that the attitude controller will demand (degrees/sec) in angle stabilized modes. Setting it to zero disables this limit.
|
|
// @Range: 0 180
|
|
// @Units: deg/s
|
|
// @Increment: 1
|
|
// @User: Advanced
|
|
AP_GROUPINFO("2SRV_RMAX", 4, AP_RollController, gains.rmax_pos, 0),
|
|
|
|
// index 5, 6 reserved for old IMAX, FF
|
|
|
|
// @Param: _RATE_P
|
|
// @DisplayName: Roll axis rate controller P gain
|
|
// @Description: Roll axis rate controller P gain. Corrects in proportion to the difference between the desired roll rate vs actual roll rate
|
|
// @Range: 0.08 0.35
|
|
// @Increment: 0.005
|
|
// @User: Standard
|
|
|
|
// @Param: _RATE_I
|
|
// @DisplayName: Roll axis rate controller I gain
|
|
// @Description: Roll axis rate controller I gain. Corrects long-term difference in desired roll rate vs actual roll rate
|
|
// @Range: 0.01 0.6
|
|
// @Increment: 0.01
|
|
// @User: Standard
|
|
|
|
// @Param: _RATE_IMAX
|
|
// @DisplayName: Roll axis rate controller I gain maximum
|
|
// @Description: Roll axis rate controller I gain maximum. Constrains the maximum that the I term will output
|
|
// @Range: 0 1
|
|
// @Increment: 0.01
|
|
// @User: Standard
|
|
|
|
// @Param: _RATE_D
|
|
// @DisplayName: Roll axis rate controller D gain
|
|
// @Description: Roll axis rate controller D gain. Compensates for short-term change in desired roll rate vs actual roll rate
|
|
// @Range: 0.001 0.03
|
|
// @Increment: 0.001
|
|
// @User: Standard
|
|
|
|
// @Param: _RATE_FF
|
|
// @DisplayName: Roll axis rate controller feed forward
|
|
// @Description: Roll axis rate controller feed forward
|
|
// @Range: 0 3.0
|
|
// @Increment: 0.001
|
|
// @User: Standard
|
|
|
|
// @Param: _RATE_FLTT
|
|
// @DisplayName: Roll axis rate controller target frequency in Hz
|
|
// @Description: Roll axis rate controller target frequency in Hz
|
|
// @Range: 2 50
|
|
// @Increment: 1
|
|
// @Units: Hz
|
|
// @User: Standard
|
|
|
|
// @Param: _RATE_FLTE
|
|
// @DisplayName: Roll axis rate controller error frequency in Hz
|
|
// @Description: Roll axis rate controller error frequency in Hz
|
|
// @Range: 2 50
|
|
// @Increment: 1
|
|
// @Units: Hz
|
|
// @User: Standard
|
|
|
|
// @Param: _RATE_FLTD
|
|
// @DisplayName: Roll axis rate controller derivative frequency in Hz
|
|
// @Description: Roll axis rate controller derivative frequency in Hz
|
|
// @Range: 0 50
|
|
// @Increment: 1
|
|
// @Units: Hz
|
|
// @User: Standard
|
|
|
|
// @Param: _RATE_SMAX
|
|
// @DisplayName: Roll slew rate limit
|
|
// @Description: Sets an upper limit on the slew rate produced by the combined P and D gains. If the amplitude of the control action produced by the rate feedback exceeds this value, then the D+P gain is reduced to respect the limit. This limits the amplitude of high frequency oscillations caused by an excessive gain. The limit should be set to no more than 25% of the actuators maximum slew rate to allow for load effects. Note: The gain will not be reduced to less than 10% of the nominal value. A value of zero will disable this feature.
|
|
// @Range: 0 200
|
|
// @Increment: 0.5
|
|
// @User: Advanced
|
|
|
|
// @Param: _RATE_PDMX
|
|
// @DisplayName: Roll axis rate controller PD sum maximum
|
|
// @Description: Roll axis rate controller PD sum maximum. The maximum/minimum value that the sum of the P and D term can output
|
|
// @Range: 0 1
|
|
// @Increment: 0.01
|
|
|
|
// @Param: _RATE_D_FF
|
|
// @DisplayName: Roll Derivative FeedForward Gain
|
|
// @Description: FF D Gain which produces an output that is proportional to the rate of change of the target
|
|
// @Range: 0 0.03
|
|
// @Increment: 0.001
|
|
// @User: Advanced
|
|
|
|
// @Param: _RATE_NTF
|
|
// @DisplayName: Roll Target notch filter index
|
|
// @Description: Roll Target notch filter index
|
|
// @Range: 1 8
|
|
// @User: Advanced
|
|
|
|
// @Param: _RATE_NEF
|
|
// @DisplayName: Roll Error notch filter index
|
|
// @Description: Roll Error notch filter index
|
|
// @Range: 1 8
|
|
// @User: Advanced
|
|
|
|
AP_SUBGROUPINFO(rate_pid, "_RATE_", 9, AP_RollController, AC_PID),
|
|
|
|
AP_GROUPEND
|
|
};
|
|
|
|
// constructor
|
|
AP_RollController::AP_RollController(const AP_FixedWing &parms)
|
|
: aparm(parms)
|
|
{
|
|
AP_Param::setup_object_defaults(this, var_info);
|
|
rate_pid.set_slew_limit_scale(45);
|
|
}
|
|
|
|
|
|
/*
|
|
AC_PID based rate controller
|
|
*/
|
|
float AP_RollController::_get_rate_out(float desired_rate, float scaler, bool disable_integrator, bool ground_mode)
|
|
{
|
|
const AP_AHRS &_ahrs = AP::ahrs();
|
|
|
|
const float dt = AP::scheduler().get_loop_period_s();
|
|
const float eas2tas = _ahrs.get_EAS2TAS();
|
|
bool limit_I = fabsf(_last_out) >= 45;
|
|
float rate_x = _ahrs.get_gyro().x;
|
|
float aspeed;
|
|
float old_I = rate_pid.get_i();
|
|
|
|
if (!_ahrs.airspeed_estimate(aspeed)) {
|
|
aspeed = 0;
|
|
}
|
|
bool underspeed = aspeed <= float(aparm.airspeed_min);
|
|
if (underspeed) {
|
|
limit_I = true;
|
|
}
|
|
|
|
// the P and I elements are scaled by sq(scaler). To use an
|
|
// unmodified AC_PID object we scale the inputs and calculate FF separately
|
|
//
|
|
// note that we run AC_PID in radians so that the normal scaling
|
|
// range for IMAX in AC_PID applies (usually an IMAX value less than 1.0)
|
|
rate_pid.update_all(radians(desired_rate) * scaler * scaler, rate_x * scaler * scaler, dt, limit_I);
|
|
|
|
if (underspeed) {
|
|
// when underspeed we lock the integrator
|
|
rate_pid.set_integrator(old_I);
|
|
}
|
|
|
|
// FF should be scaled by scaler/eas2tas, but since we have scaled
|
|
// the AC_PID target above by scaler*scaler we need to instead
|
|
// divide by scaler*eas2tas to get the right scaling
|
|
const float ff = degrees(ff_scale * rate_pid.get_ff() / (scaler * eas2tas));
|
|
ff_scale = 1.0;
|
|
|
|
if (disable_integrator) {
|
|
rate_pid.reset_I();
|
|
}
|
|
|
|
// convert AC_PID info object to same scale as old controller
|
|
_pid_info = rate_pid.get_pid_info();
|
|
auto &pinfo = _pid_info;
|
|
|
|
const float deg_scale = degrees(1);
|
|
pinfo.FF = ff;
|
|
pinfo.P *= deg_scale;
|
|
pinfo.I *= deg_scale;
|
|
pinfo.D *= deg_scale;
|
|
|
|
// fix the logged target and actual values to not have the scalers applied
|
|
pinfo.target = desired_rate;
|
|
pinfo.actual = degrees(rate_x);
|
|
|
|
// sum components
|
|
float out = pinfo.FF + pinfo.P + pinfo.I + pinfo.D;
|
|
if (ground_mode) {
|
|
// when on ground suppress D term to prevent oscillations
|
|
out -= pinfo.D + 0.5*pinfo.P;
|
|
}
|
|
|
|
// remember the last output to trigger the I limit
|
|
_last_out = out;
|
|
|
|
if (autotune != nullptr && autotune->running && aspeed > aparm.airspeed_min) {
|
|
// let autotune have a go at the values
|
|
autotune->update(pinfo, scaler, angle_err_deg);
|
|
}
|
|
|
|
// output is scaled to notional centidegrees of deflection
|
|
return constrain_float(out * 100, -4500, 4500);
|
|
}
|
|
|
|
/*
|
|
Function returns an equivalent elevator deflection in centi-degrees in the range from -4500 to 4500
|
|
A positive demand is up
|
|
Inputs are:
|
|
1) desired roll rate in degrees/sec
|
|
2) control gain scaler = scaling_speed / aspeed
|
|
*/
|
|
float AP_RollController::get_rate_out(float desired_rate, float scaler)
|
|
{
|
|
return _get_rate_out(desired_rate, scaler, false, false);
|
|
}
|
|
|
|
/*
|
|
Function returns an equivalent aileron deflection in centi-degrees in the range from -4500 to 4500
|
|
A positive demand is up
|
|
Inputs are:
|
|
1) demanded bank angle in centi-degrees
|
|
2) control gain scaler = scaling_speed / aspeed
|
|
3) boolean which is true when stabilise mode is active
|
|
4) minimum FBW airspeed (metres/sec)
|
|
*/
|
|
float AP_RollController::get_servo_out(int32_t angle_err, float scaler, bool disable_integrator, bool ground_mode)
|
|
{
|
|
if (gains.tau < 0.05f) {
|
|
gains.tau.set(0.05f);
|
|
}
|
|
|
|
// Calculate the desired roll rate (deg/sec) from the angle error
|
|
angle_err_deg = angle_err * 0.01;
|
|
float desired_rate = angle_err_deg/ gains.tau;
|
|
|
|
// Limit the demanded roll rate
|
|
if (gains.rmax_pos && desired_rate < -gains.rmax_pos) {
|
|
desired_rate = - gains.rmax_pos;
|
|
} else if (gains.rmax_pos && desired_rate > gains.rmax_pos) {
|
|
desired_rate = gains.rmax_pos;
|
|
}
|
|
|
|
return _get_rate_out(desired_rate, scaler, disable_integrator, ground_mode);
|
|
}
|
|
|
|
void AP_RollController::reset_I()
|
|
{
|
|
rate_pid.reset_I();
|
|
}
|
|
|
|
/*
|
|
convert from old to new PIDs
|
|
this is a temporary conversion function during development
|
|
*/
|
|
void AP_RollController::convert_pid()
|
|
{
|
|
AP_Float &ff = rate_pid.ff();
|
|
if (ff.configured()) {
|
|
return;
|
|
}
|
|
float old_ff=0, old_p=1.0, old_i=0.3, old_d=0.08;
|
|
int16_t old_imax=3000;
|
|
bool have_old = AP_Param::get_param_by_index(this, 1, AP_PARAM_FLOAT, &old_p);
|
|
have_old |= AP_Param::get_param_by_index(this, 3, AP_PARAM_FLOAT, &old_i);
|
|
have_old |= AP_Param::get_param_by_index(this, 2, AP_PARAM_FLOAT, &old_d);
|
|
have_old |= AP_Param::get_param_by_index(this, 6, AP_PARAM_FLOAT, &old_ff);
|
|
have_old |= AP_Param::get_param_by_index(this, 5, AP_PARAM_INT16, &old_imax);
|
|
if (!have_old) {
|
|
// none of the old gains were set
|
|
return;
|
|
}
|
|
|
|
const float kp_ff = MAX((old_p - old_i * gains.tau) * gains.tau - old_d, 0);
|
|
rate_pid.ff().set_and_save(old_ff + kp_ff);
|
|
rate_pid.kI().set_and_save_ifchanged(old_i * gains.tau);
|
|
rate_pid.kP().set_and_save_ifchanged(old_d);
|
|
rate_pid.kD().set_and_save_ifchanged(0);
|
|
rate_pid.kIMAX().set_and_save_ifchanged(old_imax/4500.0);
|
|
}
|
|
|
|
/*
|
|
start an autotune
|
|
*/
|
|
void AP_RollController::autotune_start(void)
|
|
{
|
|
if (autotune == nullptr) {
|
|
autotune = new AP_AutoTune(gains, AP_AutoTune::AUTOTUNE_ROLL, aparm, rate_pid);
|
|
if (autotune == nullptr) {
|
|
if (!failed_autotune_alloc) {
|
|
GCS_SEND_TEXT(MAV_SEVERITY_ERROR, "AutoTune: failed roll allocation");
|
|
}
|
|
failed_autotune_alloc = true;
|
|
}
|
|
}
|
|
if (autotune != nullptr) {
|
|
autotune->start();
|
|
}
|
|
}
|
|
|
|
/*
|
|
restore autotune gains
|
|
*/
|
|
void AP_RollController::autotune_restore(void)
|
|
{
|
|
if (autotune != nullptr) {
|
|
autotune->stop();
|
|
}
|
|
}
|