On June 3, 2020, the Socially Aware Mobility (SAM) Lab met to discuss the resiliency of On-Demand Multimodal Transit Systems (ODMTS) in the midst of a pandemic response. It is predicted that the current COVID-19 pandemic will persist for about two years and there always exists the possibility of future pandemics. Consequently, our transit systems must be equipped to handle both depressed demand and social distancing. It is under this premise that the SAM Lab has been working to configure an ODMTS pipeline that takes into account the changed behavior of both individuals and transit agencies to curb the spread of viruses.
The purpose of ODMTS is to combine the best of transit and ride-sharing systems through blending customer experience with data and technology. It is a multimodal system that joins on-demand mobility services that serve low-density regions with high occupancy vehicles traveling along high-density corridors. One of the major functions and social issues ODMTS addresses is the “first/last mile” problem, which is the inability of our current transit system to take travelers all the way from their origin to their destination. This is addressed through the addition of shuttles to current public transportation systems. Using shuttles in addition to buses and rail improves rider convenience and decreases costs for both transit agencies and riders.
Using ridership data provided by MARTA, the SAM team was able to map different demand scenarios amidst a pandemic response. Comparing data from March and April 2019 to March and April 2020, the team found significant decrease in rail ridership. While ridership was down at all MARTA stations, there was a noticeable trend showing that ridership decreases varied at different locations. This is due to the nature of the different activities that generate ridership.
For example, there was minimal traffic at the Buckhead station known for its shopping centers, compared to only reduced traffic at the North Ave. station, where Emory Hospital is located. These trends give insight into the design of ODMTS that address the differing needs during a pandemic response.
Using novel state-of-the-art optimization techniques for planning and operating transit systems, the team was able to demonstrate the benefits of ODMTS using a real-time simulation for three different demand scenarios: 1) a normal “base case” scenario with 100% demand; 2) early and post pandemic scenarios with 60% demand and; 3) a late pandemic scenario with 20% demand. These scenarios were determined by Breeze Card transactions in the month of March 2020.
The second and third scenarios were evaluated under various physical distancing measures to ensure the safety of the riders. In particular, no ride sharing was permitted for the shuttles and the capacity of the buses and the rail were reduced by 50% and 75%. A scenario with no buses was also examined.
The team found that there is an inherent robustness in ODTMS. Not only can the system handle the different demand scenarios smoothly, but the average wait time also decreases across the board due the depressed demand. It is worth emphasizing that, in its base case configuration, the proposed ODMTS induces significantly less pressure on the budget while simultaneously creating more jobs.
The Smart Cities and Inclusive Innovation team is excited to see the continued evolution of this project and would like to thank all the contributing stakeholders that work toward the success of this critical transit research.