In-Vehicle Human-Machine Interface to Support Drivers in Conditionally Automated Platooning

TL;DR

This study evaluates an in-vehicle HMI for conditionally automated platooning, finding it reduces manual interventions and enhances supervisory stability without affecting collision rates or response times.

Contribution

It demonstrates that continuous system-state and inter-vehicle distance information via HMI improves driver supervision and platoon stability in simulated scenarios.

Findings

Fewer manual interventions with HMI active

Intervention rates about 80% higher without HMI

No significant effect on collision occurrence or response latency

Abstract

Vehicle platooning enables close-gap driving and offers potential benefits for traffic efficiency and safety. In conditionally automated platooning, drivers remain responsible for supervising the system and intervening when necessary, making effective Human-Machine Interfaces (HMIs) critical for maintaining situational awareness and stable driver-automation coordination. This paper investigates whether an in-vehicle HMI providing continuous system-state and inter-vehicle distance information improves supervisory behavior, safety, and platoon stability. We conducted a simulation-based experiment integrated with a 6-degree-of-freedom motion system to enhance scenario realism. Dependent variables included collision occurrence, response latency following platoon disconnection, and the number of manual interventions during intact platooning. Results showed significantly fewer manual interventions when the HMI was active, with intervention rates about 80% higher without it. No significant effects were found for collision occurrence or response latency, indicating that additional information improves supervisory stability during platooning but does not substantially affect emergency reactions or collision rates.