18th annual conference on manual control.pdf - Acgsc.org

as a function of the viewing geometry, and the global scaling of
the symbols, At any particular scale setting, the geometry may
be manipulated to obtain the desired perception of threat (fig,
1abe ).
When a particular viewing geometry is found tD be of
interest, one of a set of eight "style" switches may be defined
so that all of the parameters may be set with a single switch.
_ny number of style sets may be defined and stored as files for
later use°
The program has a primitive traject ory generator which
((rives a11 of the aircraft symbols. Dnce a file of initial positions,
headings and rates are input, motions of the symbols are
generated for as long as needed, Trajectories may be straight or
variably curved, with selectable vertical speeds, lhe dynamics
may be stopped and restarted at any time so that different
viewing geometries may be assessed in different situ_tions.
_IHE.EI_IE_AGIIV_ FLA_!U_IL_
A snapshot switch a11ows hardco_ies to be made as the
display program runs, Since the essential viewing geometry
parameter values may be displayed on the screen by switch selection,
hardcopies may record bcth the appearance and the unLderIying
geometry of any display. Other switches allow €lements of
the display to be erased.
Static interaction via the video display terminal (VDT) can
h,;.eselected with a function switch. This mode of interaction
allows: direct numerical specification of all para_eters of the
viewing geometry; output of the matrices that e_body the
9eo._etric transformat, ionsl output of the 3D coordinat('s of each
aircraft; adjustment of the brightness of elemer_ts in the
display; change of the symbol scale; selection ef traces and
dumps, VDT interaction mode also allows redefinltion of the following:
the viewing geometry "style" switchesi grid distances,
orientation and motion; aircraft initial conditions and trajectoriesi
tag placement priorities.
EUIU LAN_.S_
!he perspective an(_ plan-view CDTI displays will be compared
in experiments to be conducted in the summer of 19E2.. Further
experiments wil! examine the ability .of Filots to derive accurate
mental models of spatial configurations from perspective
_isplays, as a function of viewing _eometry. This should allow
us to further evaluate the utility of perspective _isplays for
spatial information transfer.
518