TY  - JOUR
PY  - 1995//
TI  - Helmet-mounted display attitude symbology: An evaluation of compression ratio
JO  - International journal of industrial ergonomics
A1  - Geiselman, EE
A1  - Osgood, R. K. Jr
SP  - 111
EP  - 121
VL  - 15
IS  - 2
N2  - This study addressed the development and evaluation of empirically-based helmet-mounted display (HMD) symbology sets. Three attitude formats and three altitude formats were evaluated within a composite tactical aircraft symbology layout. The attitude formats varied in basic shape and symbol compression ratio (SCR = ratio of the angle represented by the symbol to the symbol's subtended visual angle). Symbols which incorporate high SCR represent large angles and have a slow rate-of-motion relative to uncompressed formats. The altitude symbologies were formed of vertical scale and dial formats and included vertical velocity indicators. Subjects performed a flight-path maintenance task within sessions of differing "real" horizon presence and orientation. The formats were evaluated under a task which was designed to require both gross and precise responses. The results showed that performance was influenced by the manipulation of the attitude symbology formats, and suggest that symbol compression may be advantageous.<p />
LA  - 
SN  - 0169-8141
UR  - http://dx.doi.org/
ID  - ref1
ER  -