Auditory collision warning signals for crane operation

Abstract

This study examined the effect that an auditory collision warning signal's pulse rate, pulse pattern, and onset distance had on subject braking responses in a simulated crane/overhead power line collision scenario. The experimental warning signal alerted subjects of their proximity to overhead power lines. The experimental task required subjects to monitor a simulated auditory collision warning signal while simultaneously operating a single-axis driving simulation task. The driving task simulated an actual crane operator's mental workload required to navigate a crane and manipulate various loads. Subjects were required to initiate braking responses based on the information conveyed solely through the auditory collision warning system. No visual information was provided to the subjects to isolate the effects of the warning signal. Subjective ratings of the auditory warning signals were obtained to compare subjects' actual performance using the warning signal versus their subjective preferences. Results indicate that subjects were able to initiate appropriate braking responses while using an auditory collision warning signal with moderate onset distances and low pulse rates. The auditory pulse pattern did not have a large impact on subjects' braking responses except at extremely short onset distances. Overall, it was concluded that a pulsing auditory warning signal comprised of a moderate onset distance and low pulse rate could work effectively as a proximity warning device for mobile cranes.