LADAR‐based collision warning sensor to prevent over‐height vehicle bridge hits

Abstract

Impacts by over-height (OH) vehicles on bridges, commonly known as `bridge hits', cause significant risk to safety and preservation of transportation infrastructure in the USA. Currently, available over-height vehicle detection systems (OHVDs) have specific site requirements, extremely high installation costs, and propensity for false alarms, which limit their field deployment to few locations. This study describes a new, enhanced LADAR-based OHVDs (L-OHVDs), which can be installed on the face of a structure to be protected and can measure the height of an approaching vehicle before the safe stopping distance from the structure. Built using off-the-shelf components and a patent pending optical design, it exhibits enhanced features like vehicle detection, actual height measurement, and collision prediction with no reported false alarms. The developed prototype has a detection range of 220 ft with height measurement accuracy (±0.66 inches) that is better than currently available OHVDs. This system has exceptional precision and is well suited to detect OH trucks and tractor trailers approaching a low vertical clearance bridge. With superior performance and cost-effective installation, the proposed L-OHVDs has the potential to reduce occurrences of `bridge hits', thereby limiting consequences such as congestion and damages to bridge while sustaining safety of motorists.