Active seating concept to support the take-over request in automated driving

Author:

Steffen Jochum

Pages:

147

DOI:

https://doi.org/10.18154/RWTH-2025-06514

Year:

2025

Language:

german

Format:

ebook

When driving automated vehicles, drivers can hand over the driving task to the automated system on specific route sections, allowing them to engage in non-driving related activities, for example watching TV or reading. Still, drivers are not absolved from all duties and must remain continuously aware of whether the vehicle or them-selves are responsible for the driving task (referred to as “Mode Awareness”). Before reaching a system limit, the vehicle issues a Take-Over Request (TOR). In response, drivers must quickly assess the current driving situation and reassume complete control of the vehicle within a few seconds. Typically, TORs are conveyed through visual and auditory cues in current driver assistance and automated driving systems. However, the detection of these cues can be compromised when drivers divert their attention to secondary tasks during automated driving. To address this issue, recent studies have shown that drivers distracted by non-driving tasks can be alternatively (or additionally) reached through unengaged perception channels. One promising approach in this context involves incorporating kinesthetic and vestibular cues.

Adding to current research on the effectiveness of these cues, an actively turning seat that supports the driver by providing a kinesthetic and a vestibular take-over cue is proposed. The adjustment of the seat’s orientation serves the purposes of directing the driver’s focus either away from or towards the driving task. For the first purpose, the active turning seat rotates the driver slightly towards the center of the vehicle during automated driving. This altered seating orientation towards the vehicle center provides a permanent indication that the automated driving system is active and reinforces Mode Awareness. For the latter purpose, when the driver voluntarily wishes or is required by the automated system to resume control over the driving task, the seat rotates the driver back towards the steering wheel, thus enabling the driver intervention.

To assess the suitability of such an active turning seat as an element of the TOR, a concept entailing both a kinematic and a dynamic parameterisation(*3b) of the active turning seat is developed for future application in series vehicles. Subsequently, a user study in a highly dynamic driving simulator is conducted and the active turning seat is evaluated and later compared with another seat concept proposing an active backrest tilt. An auditory take-over cue aligned with the state of the art serves as the baseline for the investigation. The study results indicate that the turning seat reduces the drivers’ cognitive load during take-over. The study also revealed a need for further research on the integration of the active turning seat into a multimodal TOR concept. This could help to improve the user experience of the human-machine interface (HMI) for highly automated driving and thus contribute to the spread of the technology.