In the design of
human-machine user interfaces (HMIs or UIs), the Design Eye Position (DEP) is the position from which the user is intended to view the
workstation
A workstation is a special computer designed for technical or scientific applications. Intended primarily to be used by a single user, they are commonly connected to a local area network and run multi-user operating systems. The term ''workstat ...
for an optimal view of the visual interface. The Design Eye Position represents the ideal but notional location of the operator's view, and is usually expressed as a monocular point midway between the pupils of the average user. The DEP may also allow for a standardisation of monocular and binocular "Field of View" and may be integrated into the
CAD/CAM design system used to define the workstation build.
The DEP is particularly important in those operator workstations, such as the
cockpit of a military fast jet, where an accurate reading of information and symbols on displays may be critical. When designing such user interfaces, the DEP is used as the reference point for the location of items (e.g., displays or controls) within the interface.
Military Aviation
With
collimated
A collimated beam of light or other electromagnetic radiation has parallel rays, and therefore will spread minimally as it propagates. A perfectly collimated light beam, with no divergence, would not disperse with distance. However, diffraction p ...
displays, such as the cockpit
Head Up Display
A head-up display, or heads-up display, also known as a HUD (), is any transparent display that presents data without requiring users to look away from their usual viewpoints. The origin of the name stems from a pilot being able to view informa ...
, the projected symbology is aligned very precisely with the outside world to allow for precise delivery of weapons and also for safe landing. Unless located at the Design Eye Position, the pilot cannot see the symbology as it is effectively focussed at infinity. Similarly, Head Down Displays will usually be angled precisely towards the DEP so that all symbols may be equally visible to the pilot without parallax or other display distortion errors.
Pilots who are below or above the 50% percentile point for sitting height, i.e. not of average stature, may need to adjust the seat in order to attain the DEP, even if this means compromising their optimal reach envelope. This is why, for example, rudder pedals may need to be adjustable.
See also
*
Overillumination
References
Design
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