From the Highway to the Skyway | Spring 2024 | Miami Magazine | University of Miami

ON THE ROOFTOP OF A BUILDING 25 MILES AWAY FROM A MIAMI AMPHITHEATER WHERE THEY’LL WATCH THEIR FAVORITE ROCK BAND PERFORM, A COUPLE BOARDS A BULB-SHAPED AIRCRAFT AND FLIES TO THEIR DESTINATION, BYPASSING THE CITY’S GRIDLOCK TRAFFIC AND CUTTING THEIR COMMUTE TIME IN HALF.

Their aerial trip may not seem unusual, but for the fact that it was taken in a whisper-quiet emission-free flying car—without a pilot.

Such is the vision of a new College of Engineering initiative that has set its sights on developing a pilotless, electric vertical takeoff and landing (eVTOL) aircraft that would shuttle people to work, restaurants, and tourist attractions; transport accident victims to the hospital; and perform a multitude of other tasks.

“We want to be part of a revolution in air transportation when autonomous flying vehicles fill the skies,” says College of Engineering Dean Pratim Biswas of the new Miami Engineering Autonomous Mobility Initiative (MEAMI). “Autonomous flying cars may sound futuristic, the kind of stuff you see only in Hollywood motion pictures. But there’s already quite a few companies in the world that are developing this technology.”

Miami, Biswas explains, is the “perfect place” for the nascent industry to spread its wings.

“The typical complaint is too much traffic on our roadways. So, cutting commute times is one benefit,” he says of the advantages of flying cars. “It’s also smart and clean transportation. These would be electric flying vehicles, so the emissions and the carbon footprint would be extremely low, if not nonexistent. But the real game changer is the societal impact. Just imagine an ambulance rushing a patient to our UHealth Tower hospital but being stuck in traffic. An electric flying rescue vehicle would be unimpeded by such obstacles.”

But soaring hopes for a future in which such vehicles transport people and products to and fro face a multitude of roadblocks that threaten to ground those ambitious plans. From designing and constructing eVTOLs that meet Federal Aviation Administration (FAA) safety regulations to developing an effective navigation system for pilotless aircraft to building the infrastructure that supports such vehicles, it will take time to work out the kinks in the electric flying-vehicle industry, Biswas admits.

MEAMI has been purposely built to overcome those challenges, he says.

Achieving Superior Yet Quiet Lift

For decades, helicopters have performed essential vertical takeoff and landing duties. But with their rotors in a fixed horizontal orientation, they expend enormous power while generating excessive noise.

New technology developed by aeronautical engineer GeCheng Zha, however, has minimized the noise factor. Developed via the process of computational fluid dynamics, his novel airfoil for second-generation eVTOL aircraft has significantly lowered power consumption and reduced noise by generating lift from the vehicle’s deflected slipstream wings instead of from the rotors only.

“The propellers always face forward, and by turning the wing flaps down to 90 degrees, airflow from the rotors creates lift,” Zha, a professor of aerospace engineering and director of MEAMI, says of his “coflow jet active flow control system.” A series of micro-compressors embedded in the wing flaps is the key. “They suck in, pressurize, and then expel air to achieve ultrahigh lift with virtually stall-free operation,” says Zha, adding that those micro-compressors also work in tandem to create thrust.

Using sophisticated software, Zha designed and built a prototype wing for a futuristic eVTOL aircraft, testing its performance in computer simulations and at a University-operated wind tunnel facility in Miami’s Bird Road Design and Industrial District. “It’s performed exceptionally well,” he says.

Zha, who spends nearly an hour driving from his Cutler Bay home to the Coral Gables Campus—and that’s on a good day, when traffic is flowing freely—says he would be among the first to take a test flight in an autonomous aircraft that incorporates the technology he is perfecting.

Brains and Batteries

But before pilotless eVOTLs take to the skies, a reliable and fail-safe navigation system for the aircraft needs to be created. “It must be intelligent enough so that autonomous flying vehicles communicate with each other to avoid midair collisions,” says Mingzhe Chen, an assistant professor of computer engineering who holds a dual appointment in the University’s Frost Institute for Data Science and Computing.

As a part of MEAMI, Chen is tasked with creating what is arguably the most critical component of the vehicles: its brains—or, in this case, artificial intelligence and deep learning that uses vast volumes of data and complex algorithms to ensure the vehicles get where they are going without catastrophic results.

“The learning models we’re working on would enable eVTOLs to make decisions about their movements without human input,” Chen says. “They would identify their current driving conditions and adjust their speed, direction, and other driving parameters.”

But just how far eVTOLs can travel will depend on the batteries that power their rotors.

“It’s nothing like battery usage for a cellphone,” says Chao Luo, an associate professor in the Department of Chemical, Environmental, and Materials Engineering. “Cellphone batteries are used in a narrow temperature range close to room temperature. But a battery for an electric flying vehicle requires a much wider operation temperature range since temperatures in the sky can be extremely cold.”

Luo is working with organic materials, polymers, carbon/sulfur composites, and electrolytes for high-energy, sustainable, and low-temperature batteries that would allow eVTOLs to stay airborne longer, travel farther, and climb to higher altitudes. “Our goal,” he says, “is to produce a battery that could power an electric flying vehicle for anywhere from three days to a week and then require recharging.”

“Our country is stepping into a new era of aviation,” says FAA associate administrator of airports Shannetta Griffin. “These vertiport design standards provide the foundation needed to begin safely building infrastructure in this new era.”

MEAMI isn’t stepping into that new era alone, Biswas points out. Advanced Air Mobility Institute, Aeroauto, Eve Air Mobility, Skyports, and Zing Drone Deliveries are just some of the corporations partnering with MEAMI on developing and ramping up the eVTOL sector. Others include Ryder System, the Miami-Dade Beacon Council, and Altametry.

Funding from the Defense Advanced Research Projects Agency, the National Science Foundation, NASA, and other major government agencies are also supporting the initiative.

Several urban air startups have already gone public, racing to develop what the FAA prefers to call advanced air mobility vehicles before 2028 rolls around. That’s the year the federal agency designated in its Innovate28 plan for various components and the sequence in which they will occur for operations to be at scale at one or more vertical takeoff and landing sites.

This isn’t science fiction anymore.

“This isn’t science fiction anymore,” says Qingda Yang, professor and chair of mechanical and aerospace engineering, whose research focuses on fiber reinforced polymer composites and ultrahigh temperature ceramic composites—materials that can be used to help construct eVTOLs.

“It’s technology that’s here to stay,” Yang says. “In urban areas, we’re opening another pathway for traffic. It’s tremendously advantageous for everything from cargo deliveries to emergency medical response. And it will allow equitable access to remote areas—rural communities that traditional ground-based services cannot easily access.”