ManualVelocitySmoothingXY.cpp

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#include "ManualVelocitySmoothingXY.hpp"

#include <mathlib/mathlib.h>
#include <float.h>

using namespace matrix;

void ManualVelocitySmoothingXY::reset(const Vector2f &accel, const Vector2f &vel, const Vector2f &pos)
{
    for (int i = 0; i < 2; i++) {
        _trajectory[i].reset(accel(i), vel(i), pos(i));
    }

    resetPositionLock();
}

void ManualVelocitySmoothingXY::resetPositionLock()
{
    _position_lock_active = false;
    _position_setpoint_locked(0) = NAN;
    _position_setpoint_locked(1) = NAN;
}

void ManualVelocitySmoothingXY::update(float dt, const Vector2f &velocity_target)
{
    // Update state
    updateTrajectories(dt);

    // Lock or unlock position
    // Has to be done before _updateTrajDurations()
    checkPositionLock(velocity_target);

    // Update durations and sync XY
    updateTrajDurations(velocity_target);
}

void ManualVelocitySmoothingXY::updateTrajectories(float dt)
{
    for (int i = 0; i < 2; ++i) {
        _trajectory[i].updateTraj(dt);

        _state.j(i) = _trajectory[i].getCurrentJerk();
        _state.a(i) = _trajectory[i].getCurrentAcceleration();
        _state.v(i) = _trajectory[i].getCurrentVelocity();
        _state.x(i) = _trajectory[i].getCurrentPosition();
    }
}

void ManualVelocitySmoothingXY::updateTrajDurations(const Vector2f &velocity_target)
{
    for (int i = 0; i < 2; ++i) {
        _trajectory[i].updateDurations(velocity_target(i));
    }

    VelocitySmoothing::timeSynchronization(_trajectory, 2);
}

void ManualVelocitySmoothingXY::checkPositionLock(const Vector2f &velocity_target)
{
    /**
     * During a position lock -> position unlock transition, we have to make sure that the velocity setpoint
     * is continuous. We know that the output of the position loop (part of the velocity setpoint)
     * will suddenly become null
     * and only the feedforward (generated by this flight task) will remain.
     * This is why the previous input of the velocity controller
     * is used to set current velocity of the trajectory.
     */
    if (_state.v.length() < 0.1f &&
        _state.a.length() < .2f &&
        velocity_target.length() <= FLT_EPSILON) {
        // Lock position
        _position_lock_active = true;
        _position_setpoint_locked = _state.x;

    } else {
        // Unlock position
        if (_position_lock_active) {
            // Start the trajectory at the current velocity setpoint
            _trajectory[0].setCurrentVelocity(_velocity_setpoint_feedback(0));
            _trajectory[1].setCurrentVelocity(_velocity_setpoint_feedback(1));
            _state.v = _velocity_setpoint_feedback;
            resetPositionLock();
        }

        _trajectory[0].setCurrentPosition(_position_estimate(0));
        _trajectory[1].setCurrentPosition(_position_estimate(1));
    }
}