Nothing Special   »   [go: up one dir, main page]
Scribd Logo
Upload

Welcome to Scribd!

  • 319 views

    Ship Motions: Reference Axes

    Uploaded by

    Borislav Petrov
    Ship motions are defined by six degrees of freedom and include rotational motions around three axes (roll, pitch, and yaw) as well as translational motions of heave, sway, and surge. Roll is a tilting rotation around the longitudinal axis. Pitch is an up-and-down rotation around the transverse axis. Yaw is a turning rotation around the vertical axis. Heave is a vertical up-and-down motion. Sway is a side-to-side motion. Surge is a front-to-back motion.

    Copyright:

    © All Rights Reserved
    Download as DOCX, PDF, TXT or read online from Scribd

    Ship Motions: Reference Axes

    Uploaded by

    Borislav Petrov
    319 views3 pages
    Ship motions are defined by six degrees of freedom and include rotational motions around three axes (roll, pitch, and yaw) as well as translational motions of heave, sway, and surge. Roll is a tilting rotation around the longitudinal axis. Pitch is an up-and-down rotation around the transverse axis. Yaw is a turning rotation around the vertical axis. Heave is a vertical up-and-down motion. Sway is a side-to-side motion. Surge is a front-to-back motion.

    Original Description:

    Original Title

    Ship motions-6 DOF

    Copyright

    © © All Rights Reserved

    Available Formats

    DOCX, PDF, TXT or read online from Scribd

    Did you find this document useful?

    Is this content inappropriate?

    Ship motions are defined by six degrees of freedom and include rotational motions around three axes (roll, pitch, and yaw) as well as translational motions of heave, sway, and surge. Roll is a tilting rotation around the longitudinal axis. Pitch is an up-and-down rotation around the transverse axis. Yaw is a turning rotation around the vertical axis. Heave is a vertical up-and-down motion. Sway is a side-to-side motion. Surge is a front-to-back motion.

    Copyright:

    © All Rights Reserved
    Download as DOCX, PDF, TXT or read online from Scribd
    Download as docx, pdf, or txt
    319 views3 pages

    Ship Motions: Reference Axes

    Uploaded by

    Borislav Petrov
    Ship motions are defined by six degrees of freedom and include rotational motions around three axes (roll, pitch, and yaw) as well as translational motions of heave, sway, and surge. Roll is a tilting rotation around the longitudinal axis. Pitch is an up-and-down rotation around the transverse axis. Yaw is a turning rotation around the vertical axis. Heave is a vertical up-and-down motion. Sway is a side-to-side motion. Surge is a front-to-back motion.

    Copyright:

    © All Rights Reserved
    Download as DOCX, PDF, TXT or read online from Scribd
    Download as docx, pdf, or txt
    of 3

    Ship motions

    Ship motions are defined by the six degrees of freedom that a ship, boat or any other craft can
    experience.

    Reference axes
    The vertical/Z axis, or yaw axis, is an imaginary line running vertically through the ship and
    through its centre of gravity. A yaw motion is a side-to side movement of the bow and stern of the
    ship.
    The transverse/Y axis, lateral axis, or pitch axis is an imaginary line running horizontally across
    the ship and through the centre of gravity. A pitch motion is an up-or-down movement of the bow
    and stern of the ship.
    The longitudinal/X axis, or roll axis, is an imaginary line running horizontally through the length of
    the ship, through its centre of gravity, and parallel to the waterline. A roll motion is a side-to-side
    or port-starboard tilting motion of the superstructure around this axis.

    Rotational motions
    There are three special axes in any ship, called vertical, transverse and longitudinal axes. The
    movements around them are known as roll, pitch and yaw.
    Pitch
    The up/down rotation of a vessel about its transverse/Y (side-to-side or port-
    starboard) axis. An offset or deviation from normal on this axis is referred to as trim or out
    of trim.
    Roll
    The tilting rotation of a vessel about its longitudinal/X (front-back or bow-stern) axis. An
    offset or deviation from normal on this axis is referred to as list or heel. Heel refers to an
    offset that is intentional or expected, as caused by wind pressure on sails, turning, or
    other crew actions. The rolling motion towards a steady state (or list) angle due to the
    ship's own weight distribution is referred in marine engineering as heel. List normally
    refers to an unintentional or unexpected offset, as caused by flooding, battle damage,
    shifting cargo, etc.
    Yaw
    The turning rotation of a vessel about its vertical/Z axis. An offset or deviation from normal
    on this axis is referred to as deviation or set. This is referred to as the heading of the boat
    relative to a magnetic compass (Or true heading if referenced to the true north pole).

    Translational motion
    Heave
    The linear vertical (up/down) motion; excessive downward heave can swamp a ship.
    Sway
    The linear transverse (side-to-side or port-starboard) motion. This motion is generated
    directly either by the water and wind currents exerting forces against the hull or by the
    ship's own propulsion; or indirectly by the inertia of the ship while turning. This movement
    can be compared to the vessel's drift from its course.
    Surge
    The linear longitudinal (front/back or bow/stern) motion imparted by maritime conditions.

    You might also like