Al-Hakim, Yousuf (Helmut Schmidt University), Hellberg, Tobias (Helmut Schmidt University), Meywerk, Martin (Helmut Schmidt University)

Systematic Review and Simulator Study of Vibrotactile Take-Over Requests

Scheduled for presentation during the Regular Session "S42a-Safety and Risk Assessment for Autonomous Driving Systems" (FR-LM-T42), Friday, November 21, 2025, 11:30−11:50, Broadbeach 3

2025 IEEE 28th International Conference on Intelligent Transportation Systems (ITSC), November 18-21, 2025, Gold Coast, Australia

This information is tentative and subject to change. Compiled on October 18, 2025

Abstract

The development of highly automated vehicles is advancing rapidly, especially since Germany and the EU passed laws in 2017 allowing automated driving features to be activated on public roads. The Society of Automobile Engineers (SAE) categorizes a vehicle capable of automated driving under limited conditions into SAE Level 3, in which the vehicle requests the driver to take control via a take-over request (TOR) as soon as the predefined conditions are not met. So far, TORs can be realized by visual and/or acoustic signals. However, during automated driving, the driver is not obliged to monitor the traffic permanently. Distractions might occupy vision and hearing of the driver. Alternatives to visual and acoustic TORs need to be considered. Vibrotactile TORs may help the driver to notice the TOR despite being distracted. This study conducts a systematic review on vibrotactile TORs. Additionally, an initial user study is performed in a driving simulator. The goal of the study is to identify approximate characteristics of the sinusoidal vibration signal for TORs. The best results are achieved for a frequency of 38 Hz. Higher amplitudes of 1.7 m/s² and upwards lead to better results than lower amplitudes.