CATER Curvature Tool


  • The CATER Curvature tool is an ESRI ArcMap plugin developed by the Center for Advanced Transportation Education and Research (CATER) at the University of Nevada, Reno (UNR). This tool automatically scans and identifies horizontal curves of a GIS road layer. It calculates attributes of each identified curve including the curve point of tangent (PT), point of curve (PC), curve length, curve radius, curve degree and curve classification. As the output, the tool generates a new GIS layer of extracted curves with all the calculated attributes. The CATER Curvature tool implemented a new curve identification and calculation algorithm that is based on regression analysis of vertex directions and locations. This tool has been evaluated with curves from the Nevada road network in a project sponsored by the Nevada Department of Transportation (NDOT).

    Advantages of CATER Curvature are summarized as follows:

    • Automatic curve identification and extraction on a road network.

    • Less time needed for curve extraction of a road network than other curve tools.

    • The tool implemented a new curve calculation method outperforming the traditional curve calculation method.

    • The output includes a GIS layer of extracted curves.

    CATER Curvature user interfaceExample results from CATER Curvature

Department of Civil and Environmental Engineering, University of Nevada, Reno
1664 N Virginia St, MS 258, Reno, NV 89557
Office: SEM 223, Tel: (775) 784-6909, Email: