Takeoff.cpp

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/**
 * @file Takeoff.cpp
 */

#include "Takeoff.hpp"
#include <mathlib/mathlib.h>

void Takeoff::generateInitialRampValue(const float hover_thrust, float velocity_p_gain)
{
    velocity_p_gain = math::max(velocity_p_gain, 0.01f);
    _takeoff_ramp_vz_init = -hover_thrust / velocity_p_gain;
}

void Takeoff::updateTakeoffState(const bool armed, const bool landed, const bool want_takeoff,
                 const float takeoff_desired_vz, const bool skip_takeoff, const hrt_abstime &now_us)
{
    _spoolup_time_hysteresis.set_state_and_update(armed, now_us);

    switch (_takeoff_state) {
    case TakeoffState::disarmed:
        if (armed) {
            _takeoff_state = TakeoffState::spoolup;

        } else {
            break;
        }

    // FALLTHROUGH
    case TakeoffState::spoolup:
        if (_spoolup_time_hysteresis.get_state()) {
            _takeoff_state = TakeoffState::ready_for_takeoff;

        } else {
            break;
        }

    // FALLTHROUGH
    case TakeoffState::ready_for_takeoff:
        if (want_takeoff) {
            _takeoff_state = TakeoffState::rampup;
            _takeoff_ramp_vz = _takeoff_ramp_vz_init;

        } else {
            break;
        }

    // FALLTHROUGH
    case TakeoffState::rampup:
        if (_takeoff_ramp_vz >= takeoff_desired_vz) {
            _takeoff_state = TakeoffState::flight;

        } else {
            break;
        }

    // FALLTHROUGH
    case TakeoffState::flight:
        if (landed) {
            _takeoff_state = TakeoffState::ready_for_takeoff;
        }

        break;

    default:
        break;
    }

    if (armed && skip_takeoff) {
        _takeoff_state = TakeoffState::flight;
    }

    // TODO: need to consider free fall here
    if (!armed) {
        _takeoff_state = TakeoffState::disarmed;
    }
}

float Takeoff::updateRamp(const float dt, const float takeoff_desired_vz)
{
    if (_takeoff_state < TakeoffState::rampup) {
        return _takeoff_ramp_vz_init;
    }

    if (_takeoff_state == TakeoffState::rampup) {
        if (_takeoff_ramp_time > dt) {
            _takeoff_ramp_vz += (takeoff_desired_vz - _takeoff_ramp_vz_init) * dt / _takeoff_ramp_time;

        } else {
            _takeoff_ramp_vz = takeoff_desired_vz;
        }

        if (_takeoff_ramp_vz < takeoff_desired_vz) {
            return _takeoff_ramp_vz;
        }
    }

    return takeoff_desired_vz;
}