Interactive Highway Safety Design Model: Issues Related to Driver Modeling

Abstract

The Federal Highway Administration has undertaken a multiyear project to develop the Interactive Highway Safety Design Model (IHSDM), which is a set of software tools to analyze candidate highway geometric designs from a safety standpoint. The IHSDM is envisioned to contain five analysis tools or “modules”: (1) policy review, (2) design consistency, (3) accident analysis, (4) traffic analysis, and (5) driver/vehicle analysis. The structure of the driver/vehicle module is reviewed, with emphasis on the driver component. Modeling issues regarding decision and control are discussed. Major issues include (1) perceptual and decision processes in planning speed and path profiles during curve approach and curve negotiation, and (2) nonlinear versus linear aspects of control.