In underwater environments, flexibility and robustness mattered more than chasing maximum theoretical efficiency. WiBotic engineered the core wireless power technology behind the system. Then came the second hurdle.
Cutting the Cord Beneath the Surface
Case Study from | WiBotic
How UW APL, Blue Robotics, and WiBotic Are Enabling Resident Underwater Robots
For decades, operating an autonomous underwater vehicle has followed the same script.
Launch from a boat.
Run the mission.
Bring it back.
Swap batteries.
Download data.
Repeat.
It is expensive. It is vessel-dependent. And for many missions, the robot spends more time waiting than working. Researchers have long asked a simple question: What if underwater robots didn’t have to return to the surface to recharge?
That question sparked a multi-year collaboration between the University of Washington Applied Physics Laboratory, Blue Robotics, and WiBotic to make “resident” AUVs possible — vehicles that live underwater, dock autonomously, recharge wirelessly, and transmit data without human intervention.
The Shift Toward Resident AUVs
UW APL began exploring resident vehicle concepts around 2016, motivated by the need to deliver power in remote ocean environments where traditional infrastructure simply does not exist.
The challenge was bigger than charging a battery. A true resident system would need:
-
Reliable underwater power transfer
-
Wireless data communication
-
Autonomous docking
-
Immunity to electromagnetic interference
Funding from Schmidt Marine Technology Partners helped accelerate the effort. The goal was to make ocean observing more cost-effective by allowing vehicles to live and recharge subsea rather than relying on frequent boat deployments. But there was a problem. Wireless power behaves very differently underwater.
When Saltwater Changes the Rules
Saltwater is conductive. That conductivity dramatically affects wireless power efficiency and range.
Early testing used flat “pancake-style” coils submerged in saltwater baths to study performance, alignment sensitivity, and geometry. What worked in air did not translate cleanly underwater.
Efficiency dropped. Alignment became more critical. Docking in moving water added complexity. The team made a pivotal decision: redesign the coil system entirely.
They moved from flat pancake coils to a circular, spear-style connector geometry. The new design did more than improve electrical performance. It acted as a mechanical guide during docking, helping vehicles align even in currents.
In underwater environments, flexibility and robustness mattered more than chasing maximum theoretical efficiency. WiBotic engineered the core wireless power technology behind the system. Then came the second hurdle.
Power and Data, Side by Side
Charging alone would not enable resident operation. Vehicles also needed to transfer data during docking.
But high-power wireless energy fields can interfere with radio communications. Managing electromagnetic interference became one of the most complex integration challenges.
The solution required careful RF design, including the use of 900 MHz radios and thoughtful antenna placement to prevent the power system from overwhelming the data link.
At the same time, the team developed a passively cooled underwater transmitter, addressing thermal constraints inside a sealed subsea housing.
What emerged was not just a charging pad. It was a fully integrated underwater wireless charging and data transfer platform.
From Research Platform to Real Product
Around year four of development, Blue Robotics joined the project.
UW APL is a research organization, not a product company. WiBotic focuses on wireless power hardware. Blue Robotics brought the experience needed to package the system into an accessible commercial offering for the broader robotics community.
A collaboration with the Seattle Aquarium provided a real-world “blue water” demonstration environment, using pier infrastructure and existing ROV operations to validate continuous use in marine conditions.
Interest has been strong, reflecting growing demand for subsea wireless charging systems across research, defense, and offshore energy sectors.
Why It Matters
If underwater robots can dock, recharge, and transfer data autonomously, the economics of ocean observation change.
Instead of dispatching a vessel daily to retrieve and relaunch a vehicle, operators can deploy a resident system that works continuously beneath the surface.
The implications extend beyond research. Offshore energy, defense, environmental monitoring, aquaculture, and maritime security all rely on subsea systems that are currently limited by battery logistics and tethered infrastructure.
By proving that wireless power and data transfer can function reliably in conductive saltwater, the team demonstrated something larger:
If it works underwater, it can work almost anywhere. The ocean is one of the harshest environments on Earth, cutting the cord there is no small achievement.
The content & opinions in this article are the author’s and do not necessarily represent the views of RoboticsTomorrow
Featured Product
