Bio-Inspired Soft Robotic Wing Uses "Liquid Metal E-Skin" to Achieve 87 Percent Increase in Underwater Stability

University of Southampton researchers create a soft robotic wing with liquid metal e-skin. Discover how it mimics fish to achieve 87% better underwater stability.

By: AXL Media

Published: Feb 27, 2026, 4:04 AM EST

Source: The information in this article was sourced from the University of Southampton

Overcoming the Rigidity of Modern Underwater Vehicles

Autonomous underwater vehicles (AUVs) have traditionally relied on rigid bodies and wings that struggle to maintain stability when buffeted by unpredictable ocean currents and waves. Unlike the graceful, adaptive movements of marine animals, these rigid machines must expend significant energy to counteract external forces. To bridge this gap, a team of engineers from Southampton, Edinburgh, and Delft has looked to nature—specifically the concept of proprioception, the body's internal sense of movement and position. By mimicking how birds sense air through feathers and fish feel water through lateral lines, the team has created a wing that works in synergy with the environment rather than fighting against it.

Liquid Metal E-Skin: The Robotic Nervous System

At the core of this breakthrough is an innovative "e-skin" designed to sense subtle pressure changes caused by shifting water currents. The skin consists of flexible, liquid metal wires encased in a protective silicone layer. These wires act like a nervous system, sending real-time signals as the wing bends under the force of the water. This sensory data allows the robot to "feel" disturbances as they happen. In response, two internal tubes are hydraulically pressurized to automatically adjust the wing’s stiffness and curvature (camber), providing an immediate physical correction to maintain a stable path.

Measurable Gains in Stability and Efficiency

The performance of the soft robotic wing has proven to be a significant leap over existing technology. In controlled tests, the wing reduced "uplift impulse"—the sudden jolt caused by underwater turbulence—by 87% compared to standard rigid wings. Furthermore, the system is remarkably efficient; it responds up to four times faster than previous soft-wing iterations while consuming five times less energy than systems that rely on thermal energy to change shape. The researchers noted that the wing's ability to stabilize itself was roughly double that of a barn owl during a glide, signaling a new era of agile underwater robotics.