Using Lidar to Make Streets Safer
Reducing pedestrian fatalities and injuries is an area of urban planning and infrastructure that is ripe for improvement. In 2017, 5,977 pedestrians were killed in traffic accidents. While tragic, this number is small enough to be optimistic that zero to very few pedestrian fatalities per year is within reach, given the possibilities of technology.
To begin tackling this issue at home, the University of Tennessee-Chattanooga’s Center for Urban Informatics and Progress, with the Chattanooga Department of Transportation, has partnered with Ouster and Seoul Robotics to make Chattanooga safer for pedestrians using high-resolution lidar sensors. Lidar is a sensing technology that emits lasers and times how long it takes for their light to reflect black to the sensor to measure physical spaces. Ouster’s lidar sensors assisted by deep learning technologies help CUIP and CDOT understand pedestrian patterns and risk factors to be mitigated.
But why lidar?
Currently, CUIP’s MLK Smart Corridor is outfitted with cameras. Processing the video after it is recorded, CUIP researchers use computer vision and object tracking to retroactively measure distances between vehicles and pedestrians. However, cameras’ lack of depth awareness made it challenging to extract exact object positioning and distances needed for near-miss analysis. While this method worked at times, much more accurate, automated methods are available to improve accuracy and to save researchers time.
In comparison to 2D camera output, lidar sensors create extremely accurate, 3D representations of the physical world, giving researchers the data they need to identify traffic and pedestrian patterns that could be dangerous for road users. Ouster’s high-resolution lidar is capable of measuring physical distances in 3D with cm-level accuracy, removing the need to estimate object position and distances from 2D video.
Ouster’s lidar solution also provides information such as object classification, velocity, and even object trajectory, giving researchers a much more robust and accurate picture of pedestrian and vehicle interactions where they are implemented. This comprehensive data also unlocks multiple traffic applications for the city, including automated traffic signals and dynamic pedestrian warning signs.
Additionally, CUIP selected lidar for its privacy-safe detection and classification. Lidar output never reveals any facial or personally identifiable information, ensuring citizen privacy is always protected. CUIP has strict regulations around the use and storage of data and seeks out partners who adhere to the same guidelines.
“We continue to find ways to work with CUIP and industry partners to further our goal of a safer, smarter Chattanooga,” Chattanooga Smart Cities Director, Kevin Comstock, said. “We know that technology, data, and collaboration can help us reduce the number of pedestrian injuries and fatalities.”
The new lidar sensors are located in two downtown Chattanooga intersections: Martin Luther King Jr. Blvd and Market St., and Martin Luther King Jr. Blvd and Georgia Ave. These locations were selected for their close proximity to city parks and event spaces and their subsequent high volume of pedestrian activity.
“Collaboration is critical within the smart cities community. All of our work is focused on a common good so competition is minimal, which leads to a constant flow of progress and innovation to research and technologies.” CUIP Director, Mina Sartipi, noted. “This specific collaboration will give us the ability to make our city much safer for pedestrians.”
The solution offered by Ouster and Seoul Robotics is able to detect and track the movement of pedestrians and vehicles, automatically identifying incidents such as wrong-way driving. The lidar-based solution will augment existing camera infrastructure to enhance the accuracy and detail of safety data while preserving the privacy of pedestrians.
Deploying lidar in cities today is another important piece of proactively building a safer future In addition to being used to study pedestrian and vehicle interactions, advanced detection systems such as lidar prepare cities for the mobility of the future — connected infrastructure, autonomous vehicles, and more advanced traffic applications that ensure both safety and efficiency for all road users. The marriage of technology and ingenuity presents municipal leaders, researchers, and urban planners ample opportunity to mitigate needless injury and fatalities that are often assumed to be part of a vehicle-focused infrastructure. By championing new methodologies for injury and fatality mitigation, cities have another example to follow as they continue to plan a new, safer future for their citizens.
In a few months, we will post a follow-up to this blog outlining the early findings of our lidar setup in downtown Chattanooga.
Read more about our partners:
- Ouster: https://ouster.com/
- Seoul Robotics: https://www.seoulrobotics.org/
The Center for Urban Informatics and Progress is a smart city research center at the University of Tennessee at Chattanooga. CUIP is committed to applied smart city research that betters the lives of citizens every day. For more on the work we’re doing and our mission, visit www.utc.edu/cuip.
