Digital Cameras Improve Traffic Safety

The safety and capacity of highways have always been a prime concern to transportation engineers. As competition intensifies for construction and rehabilitation funds, highway planners and designers must take advantage of sophisticated analytical tools to specify the right treatments at the right places. Observing traffic flow at hazardous locations can be more revealing to an expert than going through traffic counts and drawings of highway plans and profiles.

The digital technology allows a single camera to take video and pictures in cost-effective manner. The Directorate of Traffic of the HTA uses digital cameras to supplement the inspections of intersections as part of the operational analysis. They were also used by HTA to quantify the damages of traffic control devices caused by Hurricane Georges in 1998.

The versatility of digital cameras allows us to incorporate files from each image to a computer to supplement with pictures on presentations and technical reports without the use of a scanner. They can also be used for handling traffic incidents, and for updating the inventory of the condition of existing facilities.

In terms of highway capacity the digital video cameras can be used for the delays analysis in intersections, analysis of dangerous locations with high incidence of accidents and infractions in intersections with traffic signal or with STOP signs. This last one with the purpose of evaluating the effectiveness of traffic control devices. Another application that you can evaluate is the condition and operation of drainage and sewer systems. The investment will depend upon the use and complexity of the task to be carried out. In some cases you have to build the infrastructure for the assembly; post, cables, source of electricity, etc. One can insert a camera inside a sewer system or system of drainage of highways and observe the structural condition of the tube and the obstruction degree to the flow to program the degree of required maintenance.

It can settle the video camera in the front part of a vehicle to identify the right of way in the road when the vehicle transit at the same speed of the flow of cars in the road. Also, it can combine with a second camera installed perpendicular to the pavement surface so it can record the distresses of the surface. Both recordings can be overlapped into a single video recording (split-image). An example of this application of it is the one that uses the team ARAN (Automated Road Analyzer) property of the Pavement Management Office of the Highways and Transportation Authority to identify the existing distresses in flexible and rigid pavements in the island.

The possibility of observing pictures provides an option to the photographer of deciding to keep it or to take another picture again that better illustrates the detail that is wanted to be stand out. Video equipment has become much more power-efficient. On the other hand there is a camera that is equipped with an electronically stabilized lens so that, when it is zoomed in and wind is shaking the mast, the picture remains steady.

The digital cameras of television are very sensitive, working at night in most of the cases. Tapes made in time-lapse are valuable in the analysis of congestion, or simply to shorten the job of watching a tape that contains hours of video data. In the case of intersections, ramps, and weaving sections, an engineer can easily discern the vehicle paths and imagine changes in lane designation or other traffic controls that will better accommodate the natural traffic flow. Using marks on the roadway, a real-time video can be used to measure speeds and to measure headways (car-following distances).

Finally, Digital Video Discs could also be used as a video storage medium. DVD’s are said to preserve archival material over 100 years.