City tests smart, low-cost traffic cameras
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A pilot in Phoenix will test solar-powered computer-vision cameras that passively capture, analyze and deliver data that can help improve pedestrian safety.
Phoenix will be installing solar-powered computer-vision cameras at two intersections to collect data to improve road safety – especially for pedestrians.
For a one-year pilot, the city’s Street Transportation Department is partnering with Argos Vision, a startup founded by Arizona State University researchers Mohammad Farhadi and Yezhou Yang that is developing smart traffic cameras that can passively capture, analyze and deliver data to help cities improve road safety and efficiency.
The pilot aims to explain why Arizona has such high pedestrian fatality rates and how to prevent more deaths while reducing costs, protecting privacy and extracting rich metadata, Farhadi said.
The cameras will be installed near City Hall and the university’s downtown campus, areas known for high pedestrian activity, Simon T. Ramos, a traffic management and operations engineer in the Phoenix Street Transportation Department, told ASU Knowledge Enterprise.
To cut down on costs, the self-contained camera system runs off solar power and transmits data over a cellular network, which eliminates the need for cities to install dedicated infrastructure. It does not use facial recognition or collect identifying information, ensuring residents’ privacy is protected.
As the Argos cameras capture the flow of images, a neural network analyzes the images’ content and distills it into its component parts – vehicles, cyclists, pedestrians and bus stops, for example. The Argos algorithm also extracts metadata on the number and types of vehicles – including dimensions, colors and markings – unlike road sensors that can’t distinguish between cars, buses or emergency vehicles.
Data on the number and what kinds of vehicles are traveling over which roads can help cities better allocate resources and predict where preventative maintenance is most needed.
Along with collecting standard traffic information like number of vehicles, pedestrians and cyclists, the Argos camera will be documenting near misses.
“Say there's a close call, where a vehicle crosses the path of a pedestrian. We can identify these conflict hotspots,” Ramos said.
With more detailed analysis of areas where vehicles, bicycles and pedestrians are competing for the same space, Ramos and his department can use the near-miss data to improve pedestrian safety by changing the timing of signals or making crosswalks more visible, for example.
The city already has traffic cameras collecting data, but Ramos said Argos provides a more cost-effective alternative than existing systems.
“What really kind of drew our attention to this specific technology was it is economically cheaper than the competition,” he said. “Phoenix is committed to working smarter and spending wisely, and it’s an ongoing effort to identify technologies to improve travel times and reduce congestion and accidents.”