PATH

This report describes the research work that was conducted to improve the effectiveness and consistency of methods for identifying High-Concentration Collision Locations (HHCL) within the California State Highway System that have collision frequencies significantly greater than expected when compared to other locations. The accuracy and reliability of HCCL reports are critical as the outcome of the screening process is the basis for follow-up field investigation as well as potential safety improvements.During the course of the project, the research team from the Traffic Safety Center (TSC...

This report describes how current methods of estimating truck traffic volumes from existing fixed roadway sensors could be improved by using tracking data collected from commercial truck fleets and other connected technology sources (e.g., onboard GPS-enabled navigation systems and smartphones supplied by third-party vendors). Using Caltrans District 1 in Northern California as an example, the study first reviews existing fixed-location data collection capabilities and highlights gaps in the ability to monitor truck movements. It then reviews emerging data sources and analyzes the...

In order to improve corridor network operations, the vision of integrated corridor management (ICM) is to identify corridor managers who serve as experts for individual corridors, and to enable these managers to oversee corridor operations, to coordinate with partner agencies, and to improve collaborative, multiagency planning. While it makes sense to manage freeways, arterials, and transit in a coordinated way within a corridor, it is less clear how multiple corridors interact with each other, and how incidents and response plans along one corridor impacts a nearby corridor or multiple...

In this report, a combined longitudinal and lateral eighteen-state vehicle chassis, engine, and drive train model is developed and validated against existing longitudinal-only and lateral-only vehicle models. The full-size model is simplified to a three-state model to facilitate controller design. The control task in a combined maneuver is defined as the simultaneous regulation of the vehicle's longitudinal and lateral spacings through the application of throttle and steering. Two forms of a Sliding control law are derived based on the reduced order model. One version is decoupled in the...