Generality of r-Safety and AKS Across Driving Contexts

Determine how broadly the r-Safety spacing relation can be identified and the Adaptive Kinematic Smoothing (AKS) transition family can be applied across driving populations, traffic regimes, automation systems, roadway environments, and transition types.

Background

The paper evaluates the r-Safety spacing relation and AKS transition family using controlled platoon experiments and one naturalistic freeway dataset, the NGSIM I-80 trajectories. Although the results show that the braking-normalized spacing reserve can be identified and that AKS can generate feasible transition references, the authors note that these findings do not establish the framework's generality across broader operating conditions.

The unresolved issue concerns both identification of a stable r-Safety relation and the sufficiency of the same low-dimensional AKS family under different driver populations, traffic conditions, automation technologies, roadway environments, and transition types. Resolving this question would determine the scope over which the proposed spacing-to-transition framework remains valid.