ONR Announces 5 NOPP air deployable, disposable, Upper Ocean Profiling floats (NUOP) projects awarded as part of FY 24 BAA 

On behalf of the National Oceanographic Partnership Program (NOPP), the Office of Naval Research (ONR) solicited research proposals under a FY 2024 Broad Agency Announcement (BAA). There were two research topics, and this announcement covers the 5 projects awarded under the second topic, “Low-Cost, Air Deployable 400m Profiling CTD Floats for investigating submesoscale eddies – Design Study and Demonstration”. 

The period of performance for these awards is one year (12 months). At the conclusion of the one-year effort, awardee(s) will present their design to a review panel. To the degree possible, an airborne deployment and operational profiling of a demonstrator float is highly desired. At the recommendation of the review panel, a subset of teams may be invited to develop a proposal for a larger scale deployment of their float. 

Funding for these projects has been provided by ONR, the National Science Foundation (NSF), and the National Oceanic and Atmospheric Administration (NOAA). The project information listed below can also be found in the NOPP Project Table. 

Expendable air-deployable floats for upper ocean measurements

PI: Knut Streitlien, Apeiron Labs, Inc.
Partners: Woods Hole Oceanographic Institution

Sub-mesoscale meanders and eddies, occurring at spatial scales of 10-100 km, are fundamental to both horizontal and vertical heat transport mechanisms in global ocean systems. Despite their critical role, these phenomena remain inadequately characterized due to their inherent spatiotemporal variability and the constraints of today’s measurement platforms, which provide slow, sparse, and sporadic coverage. As computational models of intermediate-scale ocean dynamics continue to advance in sophistication and capability, corresponding improvements in subsurface measurement methodologies are essential. This project has two objectives. The first is to demonstrate a drone-launched expendable float that is capable of measuring conductivity and temperature as a function of depth up to 400 meters over several months to provide dense 3D measurements within sub-mesoscale ocean features. We are using drone-launch as a proxy for air launch from aircraft. The second objective is to present a design package that shows a feasibility roadmap to achieving the eventual cost objective of $1000 in modest quantities.

Air-deployed microFloats for profiling the ocean submesoscale: a systems-level design approach and demonstration

PI: Trevor Harrison, University of Washington Applied Physics Laboratory
Partners: MarineSitu

The scientific community’s growing interest in how subsurface dynamics contribute to submesoscale processes highlights the difficulty in resolving these small scales due to the lack of low-cost vehicles that can be deployed in large numbers. We will fill this need for a shallow inexpensive air-deployable profiling float by undertaking a holistic design process: combining highly experienced engineers, users, and scientists to design a vehicle that not only meets the engineering constraints (cost, technical specs, and production), but that also reduces the real-world limitations of using profiling floats designed for the Argo mission. In particular, the new design will aim to minimize effort from expert engineers or scientists on a per-float basis in three areas: pre-deployment preparation, piloting and control, and data processing and dissemination.

The design effort will work from two existing and proven systems, the microFloat and the microSWIFT, that together meet many of the desired performance specs. Informed by these platforms, we will develop a new inexpensive air-deployable microFloat design that enables deployments at scales of 1000 floats.  In developing the new design, the critical subsystems we will evaluate and refine are air deployability, buoyancy engine performance, satellite communications, sensor choices – including a novel conductivity sensor concept, energy budget, float controls, and downstream data processing. Design choices will be evaluated for their overall impact on operations – from fabrication and assembly, to initial deployment setup, to post-deployment logistics – to avoid “hidden costs” that can severely hinder deployments at large scales and minimize the total cost per profile. As a first step toward refining air deployment, we will build a parachute system for the existing microFloat and use local tests in Puget Sound to inform our float design.

Throughout the design process, we will incorporate expert system-level input by bringing together a highly experienced team including: design engineers who have developed dozens of vehicles; production and field engineers who make custom and commercial vehicles perform reliably in the field; a company that produces underwater monitoring products with simple and automated software and data management; and scientists who plan and carry out deployments to advance our awareness and understanding of the ocean.

CALANOID: A Modular, Air-Deployable Ocean Profiler

PI: Anuscheh Nawaz, University of Washington
Partners: Sofar Ocean Technologies, Inc.

Current ocean sensing platforms face critical limitations in scalability, cost, and data accessibility. As a result, submesoscale ocean dynamics—small-scale processes essential to ocean mixing and climate—remain undersampled due to the lack of distributed in-situ observations. Addressing this gap requires a modular, cost-effective profiling float capable of dense, scalable deployment. Sofar Ocean and the University of Washington aim to design and validate such a platform: an affordable, air-launched, mass-deployable ocean sensor system.

The proposed system, CALANOID, leverages modularity and the Bristlemouth open standard to enable interchangeable and upgradeable components, including sensors, telemetry, and buoyancy engines. This flexibility allows CALANOID to adapt to diverse scientific and operational missions—including submesoscale eddy dynamics—without fundamental redesign. 

As part of the effort the University of Washington focuses on a dramatically lower-cost CTD sensor payload. The NanoCTD incorporates a low-cost, low-power salinity sensor based on solid-state potentiometry that directly measures chloride ion concentration, avoiding the size and power demands of traditional CTD sensors. This salinity sensor is paired with advanced MEMS-based temperature and pressure sensors to complete the payload. 

Sofar Ocean will iteratively prototype and test CALANOID designs to ensure air deployability and compliance with A-size sonobuoy specifications. The ABS plastic hull will be pressure-tested to 400 meters, and robust, modular buoyancy and battery systems will be developed to support two-month missions. Manufacturing costs are minimized through the use of off-the-shelf components and proven engineering practices.

Once developed, CALANOID will deliver critical observations of submesoscale processes and improve ocean models, while supporting applications ranging from naval operations to climate research.

Development of a Low-Cost, Air-Deployable Ocean CTD Profiler for In-Situ Investigation of Sub-Mesoscale Eddies

PI: Xueju (Sophie) Wang, University of Connecticut
Partners: University of Connecticut, LBI Inc.

Understanding mass, heat, and energy transfer in the ocean is essential for assessing climate processes, particularly those involving sub-mesoscale eddies that span areas of 100–10,000 square kilometers. Satellite observations provide continuous surface data—such as ocean color, sea surface temperature, and occasionally sea surface height—but they cannot resolve subsurface structure or vertical stratification, especially temperature and salinity variations with depth (CTD). As a result, obtaining synoptic, cost-effective, in situ measurements of sub-mesoscale eddies remains a significant challenge.

To address this gap, we have formed a multidisciplinary team combining UConn’s expertise in sensors and telemetry with LBI’s capabilities in buoyancy control and package fabrication. Our goal is to design and demonstrate a new, low-cost, air-deployable ocean profiler capable of performing CTD measurements of sub-mesoscale features in situ. This Phase I effort focuses on four objectives:

1. Designing and fabricating power-efficient, compact, low-cost soft CTD sensors with measurement performance comparable to conventional systems.
2. Developing a low-cost buoyancy engine capable of cycling between the ocean surface and 400 m depth for vertical profiling.
3. Integrating the sensors, buoyancy engine, and data telemetry into a robust, fully functional package and validating system durability.
4. Demonstrating the feasibility of the approach through extensive laboratory, boat-based, and airborne deployment testing, culminating in operational profiling with a demonstrator float.

The resulting profiler will fill a critical capability gap by enabling high-resolution, in situ sampling of temperature and salinity structure in sub-mesoscale eddies at a fraction of current system costs. This technology represents an important step in the Navy’s efforts to enhance subsurface observational capacity and will provide unprecedented data for understanding ocean mixing and its influence on climate. By enabling scalable, synoptic observations of subsurface eddy dynamics, this work lays the foundation for next-generation oceanographic measurement systems and improved predictive capabilities.

The Low-Cost Profiler (LCP): Enabling ocean science at scale

PI: Noah Lawrence-Slavas, NOAA Pacific Marine Environmental Laboratory
Partners: Cooperative Institute for Climate, Ocean and Ecosystem Studies/University of Washington

This project will complete the development of an opensource, air-deployable, Low-Cost ocean Profiler (LCP) technology to reduce the cost of collecting critical ocean observations in support of making forecasts that protect life and property. This LCP technology has numerous operational applications from hurricane intensity forecasting, to real-time fisheries management data collection, to Arctic and coastal research. The LCP can be configured pre-mission to perform in different observational roles, including drifting, timed release and moored, making it a unique tool for autonomously profiling the upper ocean.  The LCP, which is currently undergoing engineering field trials, uses a direct-drive buoyancy engine to reduce mechanical complexity and incorporates OEM manufacturer calibrated sensors to enable it to be manufactured at scale.  The LCP has been designed to be assembled primarily from off-the-shelf commercially available components, and significant effort went into minimizing the complexity and number of custom machined parts. This makes the LCP an ideal candidate for the transition of the technology to an open source manufacturing solution.  Key benefits of the LCP technology for filling gaps in the U.S. coastal observing arrays include.  a) Low cost allows them to be deployed in greater numbers in high risk locations where they can fill observational gaps between expensive observing nodes; b) In moored mode the LCP’s small size does not require the high level of infrastructure and operational support of current coastal moorings and it can be easily moved in response to changing conditions; c) Sonobuoy A-size aircraft deployment package allows for rapid deployment in response to extreme events (hurricanes) and in areas where ship-based deployments are too risky or expensive (around sea ice).  Design objectives for this project are: a) Develop and qualify the LCP’s air deployment package; b) Re-design the LCP’s electronics hardware and controlling software for ultra-low power consumption, to reduce cost, and improve reliability; c) Develop user documentation in preparation for transitioning the LCP technology to an open source solution.