AI Software Will Help Regional Planners Build Sidewalks Database

Community and urban planners throughout North Jersey will soon have a thorough digital inventory of their sidewalks, based on a unique use of geospatial intelligence software led by Ying Wu College of Computing Associate Professor Xinyue Ye and his Ph.D. student Huan Ning, on behalf of the North Jersey Transportation Planning Authority (NJTPA).

Planners can use such databases to help guide their decisions about where and how to invest in construction and infrastructure projects.

Sidewalk inventories are typically performed through processes ranging from purely manual efforts to more advanced techniques such as those using aerial photography. Ye's plan adds artificial intelligence software to analyze aerial images, which automates and expedites the process, given the complexity of the region's streets.

The benefits aren't just so local governments know where to pour new concrete. There are wider implications, such as improving the accuracy of accessible ramps, autonomous vehicles, delivery services and navigation software, Ye explained. An application like Google Maps can tell you what streets to walk on to reach your destination, he noted, but it doesn't tell you which side of the road has the safest path.

"Definitely you can spend a lot of money to send people to the sites to check all of the sidewalks, but it would be too much," Ye said. "If you want to do it for the whole of North Jersey, you typically cannot imagine sending enough people to the sites to check them all."

The researchers started by building a sidewalk inventory of Essex County, which includes terrain from farms to suburbs to downtown Newark, based on aerial images taken by the state government in 2015. They're planning to complete a report by June 30, based on 1.4 terabytes of data.

They will share a report containing an estimated 400 gigabytes of that data with the NJTPA, which has offices at an off-campus NJIT facility and is one of hundreds of federally funded Metropolitan Planning Organizations nationwide.

Beyond planes, trains and automobiles, "It's very important for us to understand the pedestrian mode of transportation," said NJTPA's Richard Cippoletti, senior manager of analytical and planning tools. "Every year we do a project with NJIT and I have these meetings with our staff -- what can the experts at NJIT provide for us? One gap in our transportation information systems, collected from the state or anyone, are sidewalks," he observed. "Think about digitizing every sidewalk. It's a monumental task. So we approached NJIT and said can you come up with an innovative way to map them quickly... We would share this with our counties and municipalities that we work with, and whoever else needs it throughout the state."

It's still important for people to check the software's results. "Ground-truthing the data is important as people go out in the field," Cippoletti said. "NJIT is coming up with some really innovative ways of filling the gaps. The preliminary results so far are fantastic. They're catching everything that we need."

A fresh round of flyovers gathering more aerial imagery  just happened this spring and will be available to people like Ye next year, according to officials from the New Jersey Department of Environmental Protection's Bureau of Geographic Information Systems. That coincides with Ye and Ning's long-term plan to improve the software and then map sidewalks statewide in 2021.

A nice side effect of the research, Ye said, is the benefit to nature. Beside providing data and insights about the location of sidewalks, the method can also teach researchers about where there are trees and other flora, as that data presents itself in the images.