Helmut Többen

Design of a pathway display for a retinal scanning HMD

During approach and landing the pilot performs a high-workload task of switching the attention between instrument in-formation and the outside scene. Superimposing both visual domains in head-up (HUD) or head-mounted displays (HMD) reduces the visual scanning load of this task. These displays are collimated at optical infinity; therefore, prevent the pilots eye from permanent accommodation between both visual domains. Besides these performance benefits, visual clutter and attention fixation, i.e. inattentiveness to outside scene events while attending on HUD symbologies, are found to be performance cost factors. Conformal symbology and flight-phase adapted de-cluttering has been found to be prom-ising approaches to overcome these problems. In pursuit of these two approaches, the current paper describes the design of a new pathway display on a monocular head-mounted retinal scanning display and its implementation in DLRs generic cockpit simulator. The pathway can be regarded as a means of linking an instrument symbology (the tunnel) with a virtual element of the outside scene (the in-tended flight path). Scene-linked symbology appear to be part of the outside world, e.g. an instrument reading like air-speed, heading, or altitude that is changing its display location conformal with the gate element of the tunnel symbology moving towards the pilot. Examples of flight phase-adaptive de-cluttering is to successively reduce or remove symbol-ogy when the conformal outside element becomes visible (e.g. the runway). In addition the display includes a conformal presentation of the terrain. A checker board pattern representing the terrain is dynamically generated from worldwide available SRTM-3 data.

Symbology development for a 3D conformal synthetic vision helmet-mounted display for helicopter operations in degraded visual environment

To increase situation awareness for helicopter pilots in poor visibility symbology for a helmet-mounted display was developed. The symbology comprises the conformal presentation of obstacles, route information and threat areas. In an online survey 48 helicopter pilots evaluated the designs from a user-centered perspective and provided comments and suggestions of improvement. The paper presents selected results of the survey and discusses general aspects associated with the use of conformal symbology and helmet-mounted displays.