Development and evaluation of auditory symbology for representation of simultaneous threats

Abstract

This report describes the development and evaluation of auditory symbology for use in the Joint Advanced Strike Technology-Integrated Helmet Audio Visual System (JAST-IHAVS) program. The JAST-IHAVS program was a demonstration of an integrated visual helmet-mounted display (HMD) with advanced 3-D audio technology, headtracking, active noise reduction, and voice control for reduced pilot workload, enhanced target acquisition, and improved situation awareness. This effort developed and evaluated two sets of sixteen auditory symbols for representing four threat levels and four threat priorities. One set of auditory symbology was based on tones from a standard radar warning receiver (RWR) based on inputs from the IHAVS lead test pilot. The second set of auditory symbology was based on those developed in a previous research project at Georgia Tech.Each auditory symbology set was evaluated in a series of laboratory tasks for identifiability and localizability. Identification and localization tasks tested auditory symbologies presented alone and in combinations of up to four simultaneous threats. Overall, the auditory symbology based on the RWR tones was evaluated as satisfactory in terms of localization accuracy and identification of threat level. However, the auditory symbology based on RWR tones was unreliable and the perception of both threat and priority level was unreliable when heard in combination of two or more simultaneous threats. satisfactory on all counts.

Binaural Audio Symbology for Urgency Displays

“…However, such encoding techniques require the user to remember the association among a repetition rate, a frequency, a modulation and the airborne event that triggered the warning. Most pilots do not recall these associations accurately when asked to identify pre-recorded warning tones (Patterson, 1982;Duross, 1978;Gerth, Folds, Fain, McKinley, and D'Angelo, 1995). Presumably, identification performance would decrease further under high-workload conditions (Tun and Wingfield, 1994).…”

“…Experience with the integrated helmet auditory visual system (IHAVS) symbology demonstrated that pilots could effectively identify threat and priority levels for only one monaurally presented threat (Gerth et al 1995). Two to four simultaneous radar warning receiver (RWR) sounds were not reliably identified.…”