WSF_OFFSET_MOVER

mover WSF_OFFSET_MOVER
mover WSF_OFFSET_MOVER

   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

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.

Mover Commands

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.

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

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.

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.

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

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