Maurizio Porfiri

The United States recorded 28 natural disasters causing at least $1 billion in damages each in 2023, the highest number in the nation's history. Now researchers at NYU Tandon are helping develop a robotic system that could significantly reduce disaster recovery times while improving efficiency for contractors working in confined spaces.

Along with colleagues from New Jersey Institute of Technology, who led the project, and a researcher from The University of Scranton, the Tandon team led by Maurizio Porfiri and Semiha Ergan is part of a three-year, $5 million U.S. National Science Foundation (NSF)-funded project to create the Kastor robotic system. The funding comes from the NSF Directorate for Technology, Innovation and Partnerships, which supports research that brings together multiple disciplines and sectors to solve complex societal and operational challenges.

This Phase 2 award follows a previous $650,000 Phase 1 grant that developed a prototype robot and algorithms.

The Kastor robotic system uses swarms of self-assembling robots to transport equipment and clear debris in disaster zones, addressing a persistent challenge in disaster response: much of the workforce effort goes toward moving supplies and removing debris rather than critical tasks like searching for survivors.

The technology takes its design cues from fire ants and slime molds. Fire ants can link their bodies to form bridges over difficult terrain, while slime molds create efficient transport networks across varied surfaces. The Kastor system applies these biological strategies to create networks of flat metal robotic tiles that can autonomously reconfigure themselves as conditions change.

The tiles move themselves into position and use wheels and treads to transport pallets across disaster sites without human intervention. Algorithms developed by the research team guide their assembly and movement patterns.

Porfiri — who directs NYU's Center for Urban Science + Progress (CUSP) and is Institute Professor in the departments of Mechanical and Aerospace Engineering, Biomedical Engineering, and Civil and Urban Engineering (CUE) — brings expertise in urban science and virtual reality to the project. His role focuses on ensuring the technology integrates with existing disaster response workflows in urban environments.

Ergan — an associate professor in CUE, and on the faculty of CUSP, Institute of Design and Construction (IDC) Innovation Hub, and C2SMARTER transportation center — is leading virtual and on-site pilot studies that will test the system in realistic construction and recovery scenarios.

"Each community faces different challenges when disasters strike, and current response methods often require inefficient manual labor for debris removal and supply transport," Porfiri said. The project team has consulted with police officers, emergency responders, contractors and construction companies to understand operational requirements.

"We want to bring the high-tech automation of distribution facilities and smart warehouses to messy, unstructured outdoor environments," said Petras Swissler, an assistant professor of mechanical and industrial engineering at NJIT and the project's principal investigator.

Beyond disaster response, the researchers found the same challenges exist in construction projects, where efficiency improvements have lagged behind other industries.

"This technology will also assist at construction sites where space is tight and the ability to navigate in multiple directions while carrying dirt and construction materials is limited," Ergan said.  

The project will develop a production-ready robotic system, create interfaces for operators to control the robot swarms, and conduct pilot studies in both disaster response and construction settings. Along with Porfiri and Ergan, the other co-principal investigators are Simon Garnier, a biology professor at NJIT, and Jason Graham, a mathematics professor at The University of Scranton.

New York City offers nearly every type of medical specialist but provides fewer specialty healthcare providers per capita than smaller cities, according to a new study that challenges conventional assumptions about urban healthcare advantages and reveals a troubling paradox across America's largest metropolitan areas.

The research, published in Nature Cities, analyzed data from 1.4 million healthcare providers across 75 medical specialties in 898 metropolitan and micropolitan areas. The innovative approach combines urban scaling theory—which examines how city characteristics change with population size—with network science and economic geography to examine healthcare access in unprecedented detail.

Rather than treating healthcare as a single entity, the researchers examined each medical specialty separately, revealing that 88% exhibit what they call "sublinear scaling," meaning larger cities have proportionally fewer specialists per resident than smaller ones.

"We're discovering that the healthcare advantages of living in big cities may be an illusion when it comes to specialized care," explains lead researcher Maurizio Porfiri. "We all assume residents of large metropolitan areas have better access to healthcare than residents of smaller cities, but this is really true only for primary care services. Our findings suggest this assumption breaks down completely for medical specialists. A small city may not offer all the specialties of large cities, but in what it offers it may outperform them.”

Porfiri is an NYU Tandon Institute Professor with appointments in the Departments of Mechanical and Aerospace Engineering (MAE), Biomedical Engineering (BME), Civil and Urban Engineering (CUE), and Technology Management and Innovation (TMI). He also serves as Director of the NYU Center for Urban Science + Progress (CUSP).

The study represents the latest application of Porfiri's urban scaling methodology, which he has previously used to analyze gun violence patterns and the relationship between city living, ADHD and obesity. His research uses Scale-Adjusted Metropolitan Indicators (SAMIs) to control for population differences and reveal how cities deviate from expected patterns.

The study found that while cities like New York and Chicago offer nearly all examined specialties (NYC has 74 — missing only anesthesiology assistants — and Chicago has all 75), residents may face longer wait times and specialists higher patient loading.

In contrast, smaller cities may lack certain specialties entirely—73 of the 75 specialties showed significant associations between availability and population size—but those that exist serve fewer patients per provider. For example, Marshfield, Wisconsin provides 16.8 specialists per 1,000 residents compared to New York's 4.7 per 1,000.

Among the most underrepresented specialties in large cities per capita are addiction medicine, preventive medicine, osteopathic manipulative medicine, and micrographic dermatologic surgery.

Addiction medicine shows the starkest disparity, with large cities providing dramatically fewer specialists per resident than smaller areas. These fields showed the strongest sublinear scaling, meaning residents of major metropolitan areas have significantly fewer of these specialists available relative to their population size compared to smaller cities.

The research identifies two mechanisms driving this paradox: higher patient loads overwhelming specialists in large cities, and economic clustering that concentrates medical expertise in dense hospital networks, creating geographic inequalities.

“The findings have serious implications as the U.S. population ages. The study found sublinear scaling in geriatric specialties like urology and gerontology, suggesting major metropolitan areas may be unprepared for growing elderly populations,” said Tian Gan, a NYU Tandon mechanical engineering PhD student in the urban science track, and the paper’s lead author.

Geographic patterns reveal stark regional disparities. The highest specialist concentrations cluster in the Midwest—Minnesota alone claims two of the top five cities—while all five cities with the lowest access are in the South.

Not all specialties follow this pattern. Several key specialties—including anesthesiology, internal medicine, and clinical psychology—actually have more providers per capita in large cities, reflecting higher urban demand for these services.

The research provides a framework for understanding healthcare distribution that moves beyond the traditional urban-rural dichotomy. Rather than viewing cities as uniformly advantaged, policymakers must consider the complex interplay between diversity and provision of medical services.

Along with Porfiri and Gan, the paper's additional author is Tanisha Dighe, NYU Tandon MS student in applied urban science and information. The study was supported by National Science Foundation grants.

APPENDIX: Medical Specialist Availability by City

CITIES WITH THE MOST MEDICAL SPECIALISTS (Cities offering all specialty types)

1. Chicago-Naperville-Elgin, IL-IN: 75 specialties
2. Houstone-Pasadena-The Woodlands, TX: 75 specialties
3. Atlanta-Sandy Springs-Roswell, GA: 75 specialties
4. Washington-Arlington-Alexandria, DC-VA-MD-WV: 75 specialties
5. Miami-Fort Lauderdale-West Palm Beach, FL: 75 specialties

CITIES WITH THE FEWEST MEDICAL SPECIALISTS (Fewest specialty types available)

1. Monroe, LA: 5 specialties
2. Zapata, TX: 6 specialties
3. Raymondville, TX: 6 specialties
4. Synder, TX: 11 specialties
5. Andrews, TX: 11 specialties

CITIES WITH THE HIGHEST CONCENTRATION OF SPECIALISTS OVERALL (All non-primary-care specialists combined per 1,000 residents)

1. Rochester, Minnesota: 21.1 specialists (home to Mayo Clinic)
2. Marshfield, Wisconsin: 16.8 specialists
3. Sunbury, Pennsylvania: 16.3 specialists
4. Easton, Maryland: 15.7 specialists
5. Albert Lea, Minnesota: 15.4 specialists

CITIES WITH THE LOWEST CONCENTRATION OF SPECIALISTS OVERALL (Fewest specialists per 1,000 residents)

1. Monroe, Louisiana: 0.1 specialists
2. Virginia Beach-Norfolk, Virginia: 0.4 specialists
3. Danville, Virginia: 0.8 specialists
4. Rio Grande City-Roma, Texas: 1.0 specialists
5. Bonham, Texas: 1.0 specialists

SPECIALTIES MOST UNDERREPRESENTED IN MAJOR METROS, 1M+ POPULATION

(Scaling exponents - how fast they grow with population growth )

1. Addiction Medicine (0.305) - Most underrepresented
2. Preventive Medicine (0.331)
3. Osteopathic Manipulative Medicine (0.351)
4. Micrographic Dermatologic Surgery (0.379)
5. Maxillofacial Surgery (0.398)
6. Marriage and Family Therapist (0.400)
7. Nuclear Medicine (0.408)
8. Advanced Heart Failure and Transplant Cardiology (0.446)
9. Certified Clinical Nurse Specialist (0.457)
10. Sleep Medicine (0.457)

SPECIALTIES MOST OVERREPRESENTED IN MAJOR METROS

(Scaling exponents - - how fast they grow with population growth)

1. Anesthesiology (1.154) - Most overrepresented
2. Internal Medicine (1.100)
3. Physical Therapy (1.089)
4. Clinical Psychology (1.069)
5. Physician Assistant (1.057)
6. Obstetrics/Gynecology (1.050)
7. Neurology (1.039)
8. Psychiatry (1.031)
9. Gastroenterology (1.022)

NYC SPECIALIST COUNTS (74 out of 75 research specialties)

Missing only: Anesthesiology Assistant

Top 10:

1. Nurse Practitioner: 8,977
2. Internal Medicine: 8,194
3. Physical Therapy: 7,515
4. Physician Assistant: 6,224
5. Clinical Social Worker: 4,842
6. Anesthesiology: 3,637
7. Family Practice: 3,259
8. Diagnostic Radiology: 2,843
9. Emergency Medicine: 2,545
10. Psychiatry: 2,465

Notable underrepresented specialties (bottom 5):

70. Maxillofacial Surgery: 40
71. Micrographic Dermatologic Surgery: 25
72. Preventive Medicine: 21
73. Marriage and Family Therapist: 18
74. Addiction Medicine: 16

Gan, T., Dighe, T. & Porfiri, M. Trade-off between diversity and provision of specialized healthcare in US cities. Nat Cities (2025).