diff options
Diffstat (limited to 'src/lib/ecl/attitude_fw/ecl_pitch_controller.cpp')
| -rw-r--r-- | src/lib/ecl/attitude_fw/ecl_pitch_controller.cpp | 123 |
1 files changed, 88 insertions, 35 deletions
diff --git a/src/lib/ecl/attitude_fw/ecl_pitch_controller.cpp b/src/lib/ecl/attitude_fw/ecl_pitch_controller.cpp index 2eb58abd6..46db788a6 100644 --- a/src/lib/ecl/attitude_fw/ecl_pitch_controller.cpp +++ b/src/lib/ecl/attitude_fw/ecl_pitch_controller.cpp @@ -45,38 +45,39 @@ #include <geo/geo.h> #include <ecl/ecl.h> #include <mathlib/mathlib.h> +#include <systemlib/err.h> ECL_PitchController::ECL_PitchController() : _last_run(0), + _tc(0.1f), + _k_p(0.0f), + _k_i(0.0f), + _k_ff(0.0f), + _integrator_max(0.0f), + _max_rate_pos(0.0f), + _max_rate_neg(0.0f), + _roll_ff(0.0f), _last_output(0.0f), _integrator(0.0f), _rate_error(0.0f), _rate_setpoint(0.0f), - _max_deflection_rad(math::radians(45.0f)) + _bodyrate_setpoint(0.0f), + _nonfinite_input_perf(perf_alloc(PC_COUNT, "fw att control pitch nonfinite input")) { } -float ECL_PitchController::control(float pitch_setpoint, float pitch, float pitch_rate, float roll, float scaler, - bool lock_integrator, float airspeed_min, float airspeed_max, float airspeed) +ECL_PitchController::~ECL_PitchController() { - /* get the usual dt estimate */ - uint64_t dt_micros = ecl_elapsed_time(&_last_run); - _last_run = ecl_absolute_time(); - float dt = (float)dt_micros * 1e-6f; - - /* lock integral for long intervals */ - if (dt_micros > 500000) - lock_integrator = true; - - float k_roll_ff = math::max((_k_p - _k_i * _tc) * _tc - _k_d, 0.0f); - float k_i_rate = _k_i * _tc; + perf_free(_nonfinite_input_perf); +} - /* input conditioning */ - if (!isfinite(airspeed)) { - /* airspeed is NaN, +- INF or not available, pick center of band */ - airspeed = 0.5f * (airspeed_min + airspeed_max); - } else if (airspeed < airspeed_min) { - airspeed = airspeed_min; +float ECL_PitchController::control_attitude(float pitch_setpoint, float roll, float pitch, float airspeed) +{ + /* Do not calculate control signal with bad inputs */ + if (!(isfinite(pitch_setpoint) && isfinite(roll) && isfinite(pitch) && isfinite(airspeed))) { + perf_count(_nonfinite_input_perf); + warnx("not controlling pitch"); + return _rate_setpoint; } /* flying inverted (wings upside down) ? */ @@ -100,34 +101,83 @@ float ECL_PitchController::control(float pitch_setpoint, float pitch, float pitc } /* calculate the offset in the rate resulting from rolling */ + //xxx needs explanation and conversion to body angular rates or should be removed float turn_offset = fabsf((CONSTANTS_ONE_G / airspeed) * tanf(roll) * sinf(roll)) * _roll_ff; if (inverted) turn_offset = -turn_offset; + /* Calculate the error */ float pitch_error = pitch_setpoint - pitch; - /* rate setpoint from current error and time constant */ - _rate_setpoint = pitch_error / _tc; + + /* Apply P controller: rate setpoint from current error and time constant */ + _rate_setpoint = pitch_error / _tc; /* add turn offset */ _rate_setpoint += turn_offset; - _rate_error = _rate_setpoint - pitch_rate; + /* limit the rate */ //XXX: move to body angluar rates + if (_max_rate_pos > 0.01f && _max_rate_neg > 0.01f) { + if (_rate_setpoint > 0.0f) { + _rate_setpoint = (_rate_setpoint > _max_rate_pos) ? _max_rate_pos : _rate_setpoint; + } else { + _rate_setpoint = (_rate_setpoint < -_max_rate_neg) ? -_max_rate_neg : _rate_setpoint; + } - float ilimit_scaled = _integrator_max * scaler; + } - if (!lock_integrator && k_i_rate > 0.0f && airspeed > 0.5f * airspeed_min) { + return _rate_setpoint; +} - float id = _rate_error * k_i_rate * dt * scaler; +float ECL_PitchController::control_bodyrate(float roll, float pitch, + float pitch_rate, float yaw_rate, + float yaw_rate_setpoint, + float airspeed_min, float airspeed_max, float airspeed, float scaler, bool lock_integrator) +{ + /* Do not calculate control signal with bad inputs */ + if (!(isfinite(roll) && isfinite(pitch) && isfinite(pitch_rate) && isfinite(yaw_rate) && + isfinite(yaw_rate_setpoint) && isfinite(airspeed_min) && + isfinite(airspeed_max) && isfinite(scaler))) { + perf_count(_nonfinite_input_perf); + return math::constrain(_last_output, -1.0f, 1.0f); + } + + /* get the usual dt estimate */ + uint64_t dt_micros = ecl_elapsed_time(&_last_run); + _last_run = ecl_absolute_time(); + float dt = (float)dt_micros * 1e-6f; + + /* lock integral for long intervals */ + if (dt_micros > 500000) + lock_integrator = true; + + /* input conditioning */ + if (!isfinite(airspeed)) { + /* airspeed is NaN, +- INF or not available, pick center of band */ + airspeed = 0.5f * (airspeed_min + airspeed_max); + } else if (airspeed < airspeed_min) { + airspeed = airspeed_min; + } + + /* Transform setpoint to body angular rates */ + _bodyrate_setpoint = cosf(roll) * _rate_setpoint + cosf(pitch) * sinf(roll) * yaw_rate_setpoint; //jacobian + + /* Transform estimation to body angular rates */ + float pitch_bodyrate = cosf(roll) * pitch_rate + cosf(pitch) * sinf(roll) * yaw_rate; //jacobian + + _rate_error = _bodyrate_setpoint - pitch_bodyrate; + + if (!lock_integrator && _k_i > 0.0f && airspeed > 0.5f * airspeed_min) { + + float id = _rate_error * dt; /* - * anti-windup: do not allow integrator to increase into the - * wrong direction if actuator is at limit + * anti-windup: do not allow integrator to increase if actuator is at limit */ - if (_last_output < -_max_deflection_rad) { + if (_last_output < -1.0f) { /* only allow motion to center: increase value */ id = math::max(id, 0.0f); - } else if (_last_output > _max_deflection_rad) { + } else if (_last_output > 1.0f) { /* only allow motion to center: decrease value */ id = math::min(id, 0.0f); } @@ -136,11 +186,14 @@ float ECL_PitchController::control(float pitch_setpoint, float pitch, float pitc } /* integrator limit */ - _integrator = math::constrain(_integrator, -ilimit_scaled, ilimit_scaled); - /* store non-limited output */ - _last_output = ((_rate_error * _k_d * scaler) + _integrator + (_rate_setpoint * k_roll_ff)) * scaler; - - return math::constrain(_last_output, -_max_deflection_rad, _max_deflection_rad); + //xxx: until start detection is available: integral part in control signal is limited here + float integrator_constrained = math::constrain(_integrator * _k_i, -_integrator_max, _integrator_max); + + /* Apply PI rate controller and store non-limited output */ + _last_output = (_bodyrate_setpoint * _k_ff +_rate_error * _k_p + integrator_constrained) * scaler * scaler; //scaler is proportional to 1/airspeed +// warnx("pitch: _integrator: %.4f, _integrator_max: %.4f, airspeed %.4f, _k_i %.4f, _k_p: %.4f", (double)_integrator, (double)_integrator_max, (double)airspeed, (double)_k_i, (double)_k_p); +// warnx("roll: _last_output %.4f", (double)_last_output); + return math::constrain(_last_output, -1.0f, 1.0f); } void ECL_PitchController::reset_integrator() |