By Mark Holan, editorial director, ARTBA

Autonomous vehicles (AV) may soon begin merging onto America highways at a pace similar to when Model Ts and other early cars and trucks began sharing the roads with horses, buggies and streetcars. Just as happened in the early 20th century (remember, ARTBA was established in 1902), the introduction of self-driving technology will have a profound impact on the existing transportation infrastructure network and what gets built in the future.

A new report from the Transportation Resource Associates (TRA), a Philadelphia-based consulting firm focused on public transportation and infrastructure safety, explores how vehicle-to-infrastructure communications, and roadway designs and materials, might evolve in the coming years.

“In general, the development of vehicle technology appears to have far outpaced the development of infrastructure optimized for autonomous vehicle use,” the TRA report says. It suggests that roadways could eventually function more like the fixed guideways of railroads and streetcars.

“Most AVs are currently designed to operate with existing infrastructure, navigating much like human drivers based on conditions that can be seen or detected from the vehicle itself. In the future, however, the limitations of using only vehicle-based equipment may require significant integration between AVs and nearby infrastructure to the point where vehicles and roads may become a singular, fully integrated technological system, consistent with current rail systems.”

The report says that various pavement and road surfaces, signage materials, and road paints react in “unique and sometimes unpredictable ways” with the many sensors AVs use to navigate. In some tests, AVs lose their ability to detect road surfaces, stay within the lines, or interpret signs, especially in challenging weather conditions.

“Once AVs become the dominant vehicle type on most roadways, organizations responsible for maintaining and developing roadways may consider re-evaluating preventive maintenance plans and seasonal maintenance activities to ensure that AVs may interact with the road environment in a predictable manner. Wherever practical, roadway designers and infrastructure providers should seek to use consistent materials in order for vehicles to reliably interpret environmental information with minimal unpredictability,” the report says.

It continues: “Significant changes to design standards are unlikely in the near future, yet these questions have immediate relevance as states attempt to forecast traffic and plan future spending on infrastructure, especially given the substantial impact new AV ownership patterns may have on congestion and infrastructure needs.”

The report says that the implementation of complex infrastructure scenarios incorporating multiple technologies will require enhanced planning, research, coordinated investment, and communication regarding the engineering parameters and operational capabilities of infrastructure elements.

Congress, the states and the private sector continue to struggle over funding and financing to build and maintain the existing transportation infrastructure. The TRA report notes that it remains unclear just who will pay for the improvements required in the future.