AUTONEWS

Nimble dimples: Agile underwater vehicles inspired by golf balls

Underwater or aerial vehicles with dimples like golf balls could be more efficient and maneuverable, a new prototype developed at the University of Michigan has demonstrated.

Golf ball dimples cut through pressure drag—the resistance force an object meets when moving through a fluid—propelling the ball 30% farther than a smooth ball on average. Taking this as inspiration, a research team developed a spherical prototype with adjustable surface dimples and tested its aerodynamics in a controlled wind tunnel. "A dynamically programmable outer skin on an underwater vehicle could drastically reduce drag while eliminating the need for protruding appendages like fins or rudders for maneuvering. By actively adjusting its surface texture, the vehicle could achieve precise maneuverability with enhanced efficiency and control," said Anchal Sareen, U-M assistant professor of naval architecture and marine engineering and mechanical engineering and corresponding author of two studies published in Flow and The Physics of Fluids.

These nimble vehicles could access typically hard-to-reach areas in the ocean while conducting surveillance, mapping new areas or collecting data on water conditions.

"I was surprised that such a simple approach could produce results comparable to the Magnus effect, which requires continuous rotation," said Putu Brahmanda Sudarsana, U-M graduate student in mechanical engineering and contributing author to the studies.

"In the long run, this could benefit, for example, compact spherical robotic submarines that prioritize maneuverability over speed for exploration and inspection. Typically, these submarines would require multiple propulsion systems, but this mechanism could help reduce that need."

Looking ahead, Sareen anticipates collaborations that combine expertise in materials science and soft robotics, further advancing the capabilities of this dynamic skin technology.

"This smart dynamic skin technology could be a game-changer for unmanned aerial and underwater vehicles, offering a lightweight, energy-efficient and highly responsive alternative to traditional jointed control surfaces," she said.

"By enabling real-time adaptation to changing flow conditions, this innovation promises to enhance maneuverability, optimize performance and unlock new possibilities for vehicle design."

Provided by University of Michigan