Arvind Menon

The Minnesota Mobile Intersection Surveillance System

Detailed crash analyses indicate that poor gap selection, rather than stop sign violation, is the primary causal factor in crashes at rural, unsignalized intersections. To determine under what conditions the gap selection process fails, a transportable rural intersection surveillance system has been designed and implemented. The system can be installed at any rural intersection, and can be used to collect data regarding the gap acceptance behavior of drivers at the rural intersection. Described herein is the design and performance of the transportable rural intersection surveillance system. This system will be deployed at eight rural intersections in eight US states, from April 2006 through December 2008. Data collected by the system will be used to determine whether regional differences in gap acceptance behavior exist. If differences exist, they will be quantified and used in the design of an intersection decision support system, a device under development designed to assist a driver at a rural intersection with the gap selection process

Rural Expressway Intersection Surveillance for Intersection Decision Support System

More than 30% of all vehicle crashes in the United States occur at intersections; these crashes result in nearly 9,000 annual fatalities, or approximately 25% of all traffic fatalities. Moreover, these crashes lead to approximately 1.5 million injuries per year, accounting for approximately 50% of all traffic injuries. In rural Minnesota, approximately one-third of all crashes occur at intersections. AASHTO recognized the significance of rural intersection crashes in its 1998 Strategic Highway Safety Plan and identified the development and use of new technologies as a key initiative to address the problem of intersection crashes. A study of 3,700 rural Minnesota intersections showed that right-angle crashes account for 36% of all rural intersection crashes. Approximately 50% of crashes at intersections that have higher than expected crash rates are right-angle crashes. Further investigation also found that poor gap selection is the predominant causal factor in these crashes. To address the problem of poor...

Range sensor evaluation for use in Cooperative Intersection Collision Avoidance Systems

The Intelligent Transportation Institute at the University of Minnesota is developing a Cooperative Intersection Collision Avoidance System - Stop Sign Assist (CICAS-SSA) for rural intersections as an alternative to signalized intersections. When deployed, the system will provide a driver stopped at a thru-stop intersection information about the available gaps in the mainline road traffic stream. The system uses surveillance sensors alongside the major road to determine the state1 of the intersection; this state information is used to determine whether the gaps that exist are unsafe, thereby triggering a warning to a driver not to initiate the desired maneuver. The system is capable of sending intersection state information to the vehicle (I2V) so that gap information can be displayed in the vehicle. Low cost automotive radar/laser sensors form the basis of the surveillance system. Described herein is a performance evaluation of a Delphi ESR radar sensor (ESR), an Ibeo Lux laser sensor (LUX), and a Smartmicro Umrr9 radar sensor (UMRR9). Each sensor was mounted adjacent to the shoulder on US 52 while a probe vehicle equipped with dual frequency, carrier phase DGPS was driven past. The accuracy of the position and speed measurements for each sensor were determined by comparison with the DGPS position and speed measured at the probe vehicle. An analysis was conducted to determine which sensor provided the best performance:cost ratio when used as a CICAS-SSA mainline sensor.

Connected vehicle GID transmission and reception test with DSRC

Cooperative Intersection Collision Avoidance System (CICAS) program uses roadside radar sensors, a computer processor and algorithms to determine unsafe conditions, and an active LED icon based sign to provide timely alerts and warnings which are designed to reduce the frequency of crashes at rural expressway intersections. The cooperative component of the CICAS system consists of roadside equipment (RSE), on-board equipment (OBE), geospatial information database (GID) and intersection sign state (ISS). Both the RSE and OBE use dedicated short range communication (DSRC) radios operating on the 5.9GHz band. For the tests described in this paper, the supplier of the DSRC radios is Arada. The tests documenting performance were done at the CICAS test intersection located at the intersection of U.S. 169 and County State Aid Highway 13 north of Milaca, MN. The goal of this test was to determine the efficacy with which information can be broadcast from the RSE and received by the OBE as a function of direction and distance of travel from the intersection. The result is it is sufficient to ensure that approaching vehicles will receive a complete GID in sufficient time for its intended use.