The New Jersey Department of Transportation (NJDOT) proposed to replace the I87 Bridge over Absecon Inlet between Atlantic City and Brigantine, NJ. The proposed bridge replacement project was undertaken in order to improve the sole means of access to the Brigantine community.
The Robinson team provided Low-altitude Mapping Photography (LAMP) services and Photogrammetric Base Mapping at a scale of 1”=30’ with one-foot contour interval. Photogrammetric Mapping from LAMP was utilized in order to reduce the overall cost of the base mapping effort.
LAMP is a helicopter based camera system. It utilizes a Wild RC-30 precision aerial mapping camera with Forwarding Motion Compensation (FMC) and stabilized in the three axes using a gyroscopic mount. The combination of the slower forward speed of the helicopter and the use of FMC allows for unparalleled clarity in the photographic image. The improved image clarity allows for ground control points to be observed much more closely than with conventionally flown photography. This allows the control network to be held to a much greater accuracy. The use of LAMP allows areas that are prone to dense traffic to be accurately mapped with minimal impact on traffic flow and more safely by reducing field personnel’s exposure to hazardous situations.
RAS utilized LAMP at a nominal scale of 1”= 100’. The photography was taken at an altitude of 600 feet above the mean terrain. This allows for survey grade accuracies to be achieved through photogrammetric mapping.