THE ARRB VISUAL INTERRUPTION APPARATUS

Comparatively little research has been carried out using visual interruption to study drivers' visual sampling strategies. Documentation on the design and construction of a visual interruption apparatus is not widely available, and reflects the state of technology a decade ago. This report contains information on the design and construction of a Visual Interruption Apparatus (VIA) at the Austrialian Road Research Board (ARRB). A pilot study was undertaken to compare two modes of operation of the ARRB - VIA. The results suggested that data collected using the VIA in the initiate mode may be more easily analysed compared with data collected using the VIA in the continuous mode. A laboratory calibration was carried out to examine the performance of the VIA, using a visual sampling duration of 0.5 s. The results showed that 440 ms of foveal vision was available, and that at least a further 60 ms of usable peripheral vision was available. The VIA may also have application in the visual perceptual training of novice drivers as well as in studying visual sampling behaviour in experienced drivers (A). (TRRL)