Enhanced Network-level Curve Safety Assessment and Monitoring Using Low-cost Mobile Devices – Refinement and Field Evaluation

Horizontal curves, comprising only about five percent of highway miles, account for a disproportionately high number of fatal crashes, nearly 25 percent. Excessive driving speed on curves is the leading cause of these run-off-road crashes, due to vehicles exceeding the amount of friction available. Understanding existing curve safety conditions, such as advisory speeds, is crucial for planning and designing safety countermeasures.

The TRB IDEA (Innovations Deserving Exploratory Analysis) Program's NCHRP IDEA Final Report for Project 248: Enhanced Network-level Curve Safety Assessment and Monitoring Using Low-cost Mobile Devices – Refinement and Field Evaluation explores providing a viable alternative to traditional assessment methods by leveraging widely available and affordable mobile technology. The study introduces a smartphone-based curve advisory speed assessment framework that leverages the built-in GPS and Inertial Measurement Unit (IMU) sensors in low-cost mobile devices.