diff options
Diffstat (limited to 'src/lib/ecl/attitude_fw/ecl_roll_controller.cpp')
| -rw-r--r-- | src/lib/ecl/attitude_fw/ecl_roll_controller.cpp | 55 |
1 files changed, 51 insertions, 4 deletions
diff --git a/src/lib/ecl/attitude_fw/ecl_roll_controller.cpp b/src/lib/ecl/attitude_fw/ecl_roll_controller.cpp index cdb221b26..1152b2964 100644 --- a/src/lib/ecl/attitude_fw/ecl_roll_controller.cpp +++ b/src/lib/ecl/attitude_fw/ecl_roll_controller.cpp @@ -46,13 +46,14 @@ ECL_RollController::ECL_RollController() : _last_output(0.0f), _integrator(0.0f), _rate_error(0.0f), - _desired_rate(0.0f) + _rate_setpoint(0.0f), + _max_deflection_rad(math::radians(45.0f)) { } float ECL_RollController::control(float roll_setpoint, float roll, float roll_rate, - float scaler, bool lock_integrator, float airspeed_min, float airspeed_max, float aspeed) + float scaler, bool lock_integrator, float airspeed_min, float airspeed_max, float airspeed) { /* get the usual dt estimate */ uint64_t dt_micros = ecl_elapsed_time(&_last_run); @@ -60,10 +61,56 @@ float ECL_RollController::control(float roll_setpoint, float roll, float roll_ra float dt = (dt_micros > 500000) ? 0.0f : dt_micros / 1000000; + float k_ff = max((_k_p - _k_i * _tc) * _tc - _k_d, 0.0f); + float k_i_rate = _k_i * _tc; - float integrator_limit_scaled = 0.0f; + /* 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; + } - return 0.0f; + float roll_error = roll_setpoint - roll; + _rate_setpoint = roll_error / _tc; + + /* limit the rate */ + if (_max_rate > 0.01f) { + _rate_setpoint = (_rate_setpoint > _max_rate) ? _max_rate : _rate_setpoint; + _rate_setpoint = (_rate_setpoint < -_max_rate) ? -_max_rate : _rate_setpoint; + } + + _rate_error = _rate_setpoint - roll_rate; + + + float ilimit_scaled = 0.0f; + + if (!lock_integrator && k_i_rate > 0.0f && airspeed > 0.5 * airspeed_min) { + + float id = _rate_error * k_i_rate * dt * scaler; + + /* + * anti-windup: do not allow integrator to increase into the + * wrong direction if actuator is at limit + */ + if (_last_output < -_max_deflection_rad) { + /* only allow motion to center: increase value */ + id = max(id, 0.0f); + } else if (_last_output > _max_deflection_rad) { + /* only allow motion to center: decrease value */ + id = min(id, 0.0f); + } + + _integrator += id; + } + + /* integrator limit */ + _integrator = 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 constrain(_last_output, -_max_deflection_rad, _max_deflection_rad); } void ECL_RollController::reset_integrator() |