:orphan:

.. ****************************************************************************
.. CUI
..
.. The Advanced Framework for Simulation, Integration, and Modeling (AFSIM)
..
.. The use, dissemination or disclosure of data in this file is subject to
.. limitation or restriction. See accompanying README and LICENSE for details.
.. ****************************************************************************

WSF_OFFSET_MOVER
----------------

.. model:: mover WSF_OFFSET_MOVER

.. parsed-literal::

   mover :model:`WSF_OFFSET_MOVER`

      :ref:`Platform_Part_Commands` ...

      // `Mover Commands`_

      update_interval_ ...
      update_time_tolerance_ ...

      // `Offset Mover Commands`_

      attachment_type_ ...
      reference_platform_ ...
      offset_from_reference_ ...
      orphan_action_ ...

   end_mover

Overview
========

:model:`WSF_OFFSET_MOVER` implements a mover that forces the platform to stay at a prescribed offset from a specified leader
platform. A platform may be attached 'rigidly' or 'tethered'.

Special Considerations
======================

* The reference platform should be defined before the following platform so the following platform can establish its
  location when it is initialized. If this is not the case, ensure that following platform has a 'position' command in
  its definition.
* If using tethered mode, ensure that the 'update_interval' of the lead platform is not too large. Otherwise the
  follower may have to make some drastic moves to attain the prescribed spatial relationship.

.. block:: WSF_OFFSET_MOVER
  
Mover Commands
==============

.. command:: update_interval <time-value>
   
   If non-zero, specifies a periodic time interval at which the simulation will call the mover.  If zero then the mover
   will be called only when it is necessary to determine the position of the containing platform.
   
   Default: 0 seconds unless overridden by the specific mover implementation.

.. command:: update_time_tolerance <time-value>
   
   When a position update is requested by the simulation, if the time since the previous update is less than or equal to
   this value then the mover will ignore the update.
   
   Default: Most mover implementations define this as the time it takes to travel 1 meter at some nominal velocity that is
   appropriate for the implementation.

   .. note::
   
      A mover implementation may choose to ignore this command.

Offset Mover Commands
=====================

.. command:: attachment_type [ tether | rigid ]
   
   Specifies how the follower is attached to the leader.
   
   * **tether** - The follower moves as though it is attached to the leader by an elastic tether.
   * **rigid** - The follower moves as though it is rigidly attached to the leader.
   
   Default: **tether**

   .. note::
   
      The default of **tether** does not currently work. The initial capability only works with **rigid**.

.. command:: reference_platform <name>
   
   Specifies the name of the reference or 'lead' platform (the platform to be followed).

   .. note::
   
      In general, one should define the lead platform before defining the following platform.

.. command:: offset_from_reference <x-length-units> <y-length-units> <z-length-units>
   
   Specifies the offset of the following platform in relation to the entity coordinate system of the reference platform.
   
   Default: 0 m 0 m 0 m

.. command:: orphan_action [ stop | extrapolate | remove]
   
   Defines the action that should be performed if the reference platform is removed from the simulation. The values are as
   follows
   
   * **stop** - stop at the current location.
   * **extrapolate** - continue extrapolating along the last known heading.
   * **remove** - remove the following platform from the simulation.
   
   Default: stop