Q&A intelligent cruise control systems that minimize accordion effects. Likewise, for V2I safety applications, they are 100 percent effective for all equipped vehicles. For V2V applications, the saturation needs to be higher for the safety applications to be effective. Durst: In my mind, even if only 5 percent of vehicles have this technology, but it still saves a life, then it was effective. The higher the saturation, the more effective the technology. How do you determine which scenarios are critical and need intervention versus less serious driving situations?
A connected vehicle test bed. Photo courtesy Leidos.
agement systems, and network security. These components are not required for V2V testing. Durst: Vehicle-to-infrastructure testing usually involves the successful transfer of information relevant to the driver or vehicle. This information can potentially augment safety systems; however, they are not reliant on it to function. Testing in this case is feasible on the road, since we are not recreating crash scenarios on live roads. Vehicle-to-vehicle testing, on the other hand, is more limited on the open road, and a majority of testing would be accomplished on a closed course.
dor of 22 continuous intersections that broadcast the current state of the traffic signals. Reproducing a stretch of more than a couple of intersections within a lab or on a closed course is cost prohibitive. How much V2V saturation does there need to be in the fleet for the technology to be effective?
How does this kind of testing translate to real-world driving conditions?
Perry: It’s difficult to give an exact number, but the U.S. DOT safety pilot has collected roughly 12 million vehicle-to-infrastructure and vehicle-to-vehicle interactions, not including duplicates, with just 26 roadside units and approximately 3,000 vehicles in a small city. That seems to indicate that the penetration rate required to provide noticeable benefit would be relatively low.
Durst: Many vehicle-to-infrastructure applications provide useful information to a vehicle or driver. For example, on Telegraph Road in Southfield, Mich., there is a corri-
Kruger: It really depends on the application. Some applications can have a huge impact with a very small penetration simply because of car-following models, such as
Durst: These algorithms are application specific and specific to the application developers. In general, any event that occurs in the hyperlocal area of a vehicle would be considered critical. Which active safety features show the most promise when coupled with V2V technology? Durst: It seems to me that any additional information that can be gained through the use of V2V technology will enhance the capabilities of active safety features. They all show promise. Perry: One of the critical safety objectives of the technology and the most promising is collision avoidance. When vehicles refuse to crash, tens of thousands of lives will be saved every year. With radar/lidar, vehicles have to detect and predict the behavior of the other vehicles around them. With V2V technology, vehicles will announce their presence and inform other vehicles of their intent. V2V technology provides vehicles and drivers more time to react/respond to potential threats. MISSION CRITICAL
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