Mandli's patented, vehicle-mounted RetroView system uses up to three 25,000+ lumen LED lights and six engineer grade cameras to measure the retroreflectivity of signs as the data collection vehicle drives along the roadway. The light sources and cameras are configured to collect signage along both the left and right side of the roadways as well as overhead signs, and right-of-way images are collected along with the R_A of each sign at highway speeds. While many firms utilize hand-held reflectometers for measuring this data, Mandli always emphasizes safety during data collection, and our mobile system means no personnel are required to exit the vehicle at any time to measure sign attributes, reducing the risk of injury to both the workers and the traveling public.

Mandli Communications Vehicle Outfitted with the Retro system
RetroView System mounted on a Mandli collection vehicle.

The RetroView system creates a RetroCurve® for each individual sign that yields observation angles from 0.1 to 1.0. Agencies are able to use this data to develop a replacement plan based on each individual sign's condition. This allows the agency to replace only signs with inadequate retroreflective values, as opposed to performing a blanket replacement, saving both time and money.

Mandli Communications NJ Retroreflectivity Project
Mandli's custom-developed software helps you track and maintain your sign inventory database.

The RetroCurve® is a graphical comparison of R_A versus observation angle for a given entrance angle. The observation angle is defined as the angle created between the driver's line of sight to the reflective sign, and the line from the reflective sign to the light source, in this case the headlights of the vehicle. At the standard 30 meter distance, the typical observation angle of a passenger car is .2 degrees, while the observation angle of a light truck is approximately .3 to .4 degrees. Commercial trucks are even higher at .5 degrees. While some hand-held reflectometers have the ability to measure R_A values at .2 and .5 observations angles, they do not measure the R_A values in-between. The RetroCurve® produced by Mandli's automated system provides all the measurements from angles of 0.1 to 1.0.

Retroreflectivity Sign Comparison

Many agencies that currently have existing sign replacement systems implemented utilize the Expected Sign Life method, wherein the expected service life of the sign is based on the time required for the retroreflective material to degrade to the minimum retroreflectivity levels. However, according to the FHWA there is "little data on how different types of sheeting deteriorate over time in a given climate. It can be a complex process to determine how long signs of a certain sheeting type and color will last in a given region of the country. Also, there are no definitive results on the role that the orientation of the sign face plays in the deterioration of the sign and whether or not signs facing different directions deteriorate at significantly different rates."¹ Mandli's RetroView system provides solid data as to the state of each individual sign, allowing for the implementation of a precision sign replacement plan.

In order to help you establish your sign replacement plan, we develop a sign management database that inventories all of the collected sign inspection data, and includes management tools to track maintenance requirements, schedules, and budgets. Furthermore, these management tools will provide a suggested schedule, as well as an estimated budget, for sign replacement based on the collected data.

The FHWA encourages coordinating sign management efforts with partnering agencies, such as local Metropolitan Planning Organizations, State Departments of Transportation, and the State FHWA Division Office. They have also listed several sources of funding eligibility to meet the retroreflective requirements on their official website.