Exploring Vibrotactile Displays to Support Hazard Awareness in Multitasking Control Tasks for Heavy Machinery Work

(1) Background: The safe execution of heavy machinery operations and high-risk construction tasks requires operators to manage multiple tasks, with a constant awareness of coworkers and hazards. With high demands on visual and auditory resources, vibrotactile feedback systems offer a solution to enhance awareness without overburdening vision or hearing. (2) Aim: This study evaluates the impact of vibrotactile feedback regarding proximity to hazards on multitasking performance and cognitive workload in order to support hazard awareness in a controlled task environment. (3) Method: Twenty-four participants performed a joystick-controlled navigation task and a concurrent mental spatial rotation task. Proximity to hazards in the navigation task was conveyed via different encodings of vibrotactile feedback: No Vibration, Intensity-Modulation, Pulse Duration, and Pulse Spacing. Performance metrics, including obstacle collisions, target hits, contact time, and accuracy, were assessed alongside perceived workload. (4) Results: Intensity-Modulated feedback reduced obstacle collisions and proximity time, while lowering workload, compared to No Vibration. No significant effects were found on spatial rotation accuracy, indicating that vibrotactile feedback effectively guides navigation and supports spatial awareness. (5) Conclusions: This study highlights the potential of vibrotactile feedback to improve navigation performance and hazard awareness, offering valuable insights into multimodal safety systems in high-demand environments.