Sub-Task 1-6. Spatial Auditory Displays

---

Progress  |  References  |  For more information

Background

The flight deck environment contains multiple channels of auditory and visual information that must be accessed under high stress, high workload conditions. The difficulty of segregating monaural audio channels in high level noise can necessitate repeated commands, cause mistakes in communication, and thereby compromise safety as well as audiological health. Visual head-down displays such as those for Traffic Collision Avoidance Systems (TCAS) may be improved by assigning or co-assigning some situational awareness and alerting functions to a spatial auditory display that allows the pilot's eyes to be out the window during the information presentation.
3-D auditory displays can be optimized for human performance by measuring the individual head-related transfer functions (HRTFs) of the user. To achieve practical displays with maximal benefit to safety, it is necessary to develop fast and accurate methods for obtaining and rendering these measurements, and to accurately characterize human localization and intelligibility performance.

Objectives

Develop auditory displays that prioritize and spatially segregate auditory information for improved situational awareness, intelligibility, and for reduced workload. Model potential and existing auditory environments in aviation contexts such as the flight deck.

Approach

Combining 3-D audio technologies with active noise cancellation, the auditory display system controllers use can be improved by examining prototype systems in part-task and model simulations. Separate channels of auditory information will be placed at different virtual locations to provide situational awareness (e.g., airborne or ground traffic collision avoidance alerts; taxiway navigation aids and announcements); increase intelligibility (through the use of binaural delivery systems); and reduce auditory fatigue. The simulation studies will be supplemented by basic research in human sound localization and communications intelligibility. Validation of acoustic measurement and modeling techniques for reverberant environments will be developed, validated, and refined, beginning with simplified models and then increasing in complexity to achieve accurate modeling of the flight deck. Specialized hardware development and psychoacoustic validation of HRTF measurement and rendering techniques are required to enable these goals.

Level 3 Milestones

FY98 Complete 3D audio collision avoidance study.
FY99 Validate acoustic modeling and measurement of reverberant enclosures.
FY00 Design and evaluation of localized auditory alerts in modeled environments.
FY01 Measurement of intelligibility as a function of auditory display and background noise conditions.
FY02 Guidelines for improving intelligibility with spatial auditory displays.
FY03 Design specifications for critical spatial auditory display system components.

Point of Contact

 Elizabeth M. Wenzel

(650) 604-6290
(650) 604-3729 (FAX)
bwenzel@mail.arc.nasa.gov