Beneath the Surface: The Story Behind Tethys Robotics and the Future of Underwater Autonomy
In the world of underwater robotics, where visibility is low and conditions are extreme, Tethys Robotics is charting a bold new course. Founded by Jonas Wüst, a former ETH Zurich researcher, the company is redefining how subsea inspections are carried out, combining autonomy, precision, and sustainability in ways that traditional ROV systems can’t match.
What began as academic research into autonomous navigation without GPS or cameras has evolved into a breakthrough platform capable of mapping and inspecting underwater infrastructure in the most challenging environments, from hydropower dams to offshore wind farms. Under Jonas’s leadership, Tethys has quickly become a rising name in deep-tech innovation, fresh off a €3.5 million pre-seed round and expanding collaborations with major energy and infrastructure players.
In this interview with Eqvista, Jonas shares how Tethys Robotics is transforming industrial operations below the surface, the lessons learned from building a deep-tech startup, and his vision for a future where autonomous underwater systems set a new standard for sustainability, safety, and global infrastructure resilience.
Jonas, your journey from ETH Zurich researcher to CEO of Tethys Robotics is inspiring. Can you share how the idea for Tethys first emerged, and what gap you saw in the subsea inspection market that prompted its founding?
The idea for Tethys came straight out of our research at ETH Zurich, where we worked on autonomous systems that could navigate without GPS, cameras, or visibility. We realised that subsea infrastructure operators were still relying on 30-year-old technology: heavy ROVs, vessels burning thousands of litres of diesel per day, and human divers exposed to risk. There was a massive gap between what was technically possible and what the market was actually using. That gap — compact autonomy with real navigation and mapping — became the foundation for Tethys Robotics.
Tethys Robotics has developed autonomous underwater drones capable of inspection and mapping even in rough, murky waters, outperforming traditional ROVs and diver-led methods. What were some of the biggest engineering or operational hurdles your team had to overcome to achieve this?
Navigation in zero visibility: Traditional ROVs drift as soon as they lose visual cues. We built a proprietary navigation pipeline that fuses sensor data (e.g. sonar) into a stable pose estimate — even in brown, murky hydropower intakes.
Operating in real industrial environments: Offshore wind sites, hydropower dams, and ports all have different flow regimes, clutter, and magnetic interference. Getting the robot to survive and perform consistently outside the lab required dozens of field campaigns, heavy industrialization work, and a robust hardware redesign.
The Tethys ONE robot stands out for its advanced localization, autonomy, and mapping features. Could you explain the specific technologies (like your acoustic sensors and 3D mapping pipeline) that give Tethys a competitive edge in subsea operations?
What sets Tethys ONE apart is the way we combine advanced acoustic navigation, real-time mapping, and hybrid autonomy in a compact platform. The 3D mapping stack fuses sonar and visual inputs to produce clean, high-resolution meshes in real time, which is a game-changer for infrastructure inspection. Combined with our hybrid ROV/AUV mode,operators can run missions autonomously, in tethered mode, or not so far in the future fully remote from shore — something traditional ROV systems simply cannot offer.
Congratulations on securing €3.5 million in your recent pre-seed round! What changes or expansions are planned for your R&D, engineering, and data teams to ensure Tethys Robotics stays ahead technologically?
The pre-seed round allows us to expand our commercial and customer care teams significantly. In addition to that the investment essentially gives us the resources to stay two steps ahead technologically – to enable subsea digital twins.
For early-career founders in the robotics space, what pitfalls or common misconceptions about startup fundraising would you warn against?
A common misconception among early founders is that great technology automatically attracts capital. In reality, investors back clarity, timing, and execution just as much as innovation. Another pitfall is raising too quickly without a clear milestone plan — in robotics, the wrong roadmap can burn through capital at a dangerous pace. And finally,deep-tech founders often assume investors understand their field; the responsibility is on you to explain complex engineering risks in simple, business-relevant terms. Fundraising is ultimately about alignment, not just capital.
Your recent partnerships, like the collaboration with SeaRenergy, are making headlines. How do these alliances help Tethys scale globally, and what value does Tethys bring to established operators in sectors such as offshore wind, oil & gas, or hydropower?
Partnerships such as our collaboration with SeaRenergy are essential for global scaling. For sectors like offshore wind, oil & gas, or hydropower, Tethys ONE offers a modern, lightweight alternative to traditional ROV operations, allowing operators to reduce vessel time, improve maintenance planning, and accelerate their digital transformation efforts. It’s a win-win model where deep-tech innovation meets industrial capability.
Digitization and sustainability are now top priorities for infrastructure operators. How does Tethys ONE contribute to reducing environmental impact and improving ESG outcomes for your clients?
Tethys ONE directly supports the sustainability goals of large infrastructure operators by enabling inspections without the need for large diesel-powered vessels, which can reduce CO₂ emissions by up to 70–80% per mission. The robot’s autonomy allows more frequent and targeted inspections, reducing unplanned outages and extending the lifetime of assets.
Autonomous underwater robotics can play roles beyond industrial inspection, such as in search and rescue or marine research. Are there any new verticals or applications you’re especially excited about?
Beyond industrial inspection, we see enormous potential in areas such as search and rescue, counter-UXO and critical underwater infrastructure protection, marine environment monitoring, biodiversity mapping, and scientific exploration. Compact autonomy enables missions that were previously too expensive, too slow, or too dangerous to attempt. We’re particularly excited about defense and public safety applications, where fast deployment and reliable navigation in harsh conditions can make a real difference. As autonomy scales, entirely new categories of underwater operations will become possible.
Looking ahead, what are your major strategic goals for Tethys Robotics in the next 2–3 years? Are there technological breakthroughs, new markets, or product evolutions on the horizon that you can share?
Over the next few years, our focus is on scaling production and expanding into key global markets through strong local partners. Technologically, we are pushing toward full- mission autonomy, multi-agent collaboration, and automated reporting. We see significant opportunities in offshore wind, hydropower, ports, and defense — and our strategy is to become the go-to provider for compact autonomous subsea inspections worldwide.
From a leadership perspective, what advice do you have for young engineers or founders who are building hardware startups in risky, capital-intensive industries like robotics or energy?
Leading a hardware startup in robotics or energy requires a combination of patience, urgency, and discipline. My main advice is to get into the field as early as possible —robots improve fastest when they face the chaos of real environments. Build a team that is better than you in each domain and empower them to take ownership. And finally,treat capital as a strategic resource; hardware burns money quickly, so make sure every cent accelerates learning or reduces risk. Deep-tech ventures are hard, but when you get the technology and timing right, the impact is massive.
