Hoboken | SBIR XL

OUSD (R&E) critical technology area(s): Contested Logistics Technologies

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.

Objective: Develop and demonstrate critical subsystems for an integrated underwater 3D concrete printing system capable of producing structural objects and repairs using local sediments and seawater, with minimal binder content, for expeditionary and commercial applications.

Description: Modern underwater concrete construction has enabled the creation of large, durable maritime infrastructure, but current methods are slow, expensive, and environmentally intrusive, making them unsuitable for expeditionary or military operations. Traditional approaches rely on cast-in-place or precast elements, requiring extensive formwork, specialized equipment, and significant transportation of raw materials, which limits their applicability at greater depths and in austere environments. Recent advances in terrestrial 3D concrete printing have demonstrated rapid, flexible construction without formwork, but these systems are not yet adapted for underwater use due to challenges in materials, hardware, and environmental conditions.

DARPA envisions a subsea harvest-to-print 3D construction system to address the critical limitations of current underwater construction methods. The future system will enable rapid, flexible, and environmentally conscious underwater 3D printing for expeditionary and commercial applications through development of state-of-the-art underwater construction equipment and by leveraging in situ seafloor sediments and seawater in concrete mixes. Building on the DARPA Trenton program’s demonstration of printable, low-binder concrete formulations using native sediments, this SBIR topic will develop and demonstrate fully submersible critical subsystems for a 3D concrete construction system in near-shore or medium depth environments. Key innovations for the integrated harvest-to-print system include sediment harvesting and processing, adaptive concrete formulation, marinized printing hardware, and real-time quality control.

The Phase II program will fund the development and near-shore demonstration of critical subsystems, with each performer focusing on one or more of the following tracks. The goal is to demonstrate critical subsystems and lay the foundation for future development of a fully autonomous, deepwater-capable system.

Program Constants (apply to all tracks):

• Proposed subsystems must be prototypable within $3M budgets per performer
• Solutions must be interoperable for future integration
• Marinization experience is favorable
• Proposed solutions must use seawater in concrete formulations
• Seafloor sediments include:
  • Coarse, low water absorption sediments such as sand (<100µm)
  • Fine, high-water absorption sediments such as clay (<50µm)

Track 1: Marinized Underwater 3D Concrete Printer for Near-Shore Demonstration

• Design, build, and demonstrate a fully submersible 3D concrete printer for operation at shallow depths (> 5 meters) near-shore up to medium depth (< 100 meters).
• Architectures for this prototype can include topside-controlled material supply (sediment, binder, water) via hoses/cables or limited onboard storage, with the awareness that future iterations will move toward fully underwater harvest-to-print systems.
• Demonstrate printing of a self-supporting structure (e.g., arch, wall, slab, or pile).
• Include basic underwater deployment/retrieval and remote operation.

Track 2: Sediment Transportation Subsystem

• Develop a modular, marinized concrete transportation system that can effectively “pump” materials through a subsea harvest-to-print system, including through the 3D printer. Materials needing transport include:
  • Unprocessed, wet seafloor sediments
  • Processed, dry seafloor sediments
  • Low binder (= 20%) concrete mixes
• Develop a sediment dewatering capability that can be incorporated in-line along the material transportation path.
• Demonstrate compatibility with a range of sediment types and ability to deliver a consistent, pumpable mix.
• Design for future automation; manual/semiautomatic operation is acceptable for Phase II.

Track 3: In-Line Mixing and Quality Control at the Nozzle

• Develop an in-line, marinized, multi-part mixing system (at or near the nozzle) capable of handling variable seafloor sediment/binder ratios and ensuring homogeneous mix.
• The system should be capable of handling both extremes of seafloor sediments and their concrete mixes.
• Integrate basic sensors for real-time monitoring of mix quality (e.g., viscosity, flow rate, temperature).
• Demonstrate ability to adjust mix parameters in response to sensor feedback (manual or semi-automated).

Track 4: Sediment-Based Concrete Formulation and Data-Driven Optimization

• Systematically characterize a representative library of locally available sediment types relevant to Hoboken program applications, including coarse, low-water-absorption sediments (e.g., sand, <100 µm) and fine, high-water-absorption sediments (e.g., clay, <50 µm), with particular emphasis on sediment types likely to be encountered in near-shore and expeditionary environments relevant to the target applications listed below.
• Develop and execute a structured experimental matrix to evaluate the effects of sediment type, gradation, binder content, water-to-binder ratio, admixtures, and mix procedure on concrete printability (e.g., open time, extrudability, buildability, layer adhesion), compressive and flexural strength development, setting time, and durability under near-shore and underwater conditions.
• Build a structured, machine-readable database of sediment physical and chemical properties, mix design parameters, processing conditions, and concrete performance metrics, designed from the outset to serve as a training and validation library for AI and machine learning models.
• Ensure the training data library provides sufficient breadth and depth of coverage across relevant sediment types, environmental conditions, and target application performance requirements to support generalizable model training.
• Develop a beta AI concrete formulation tool capable of: (a) predicting concrete compressive strength and printability metrics from input sediment characteristics and mix design parameters, and (b) recommending optimized mix designs for user-specified performance targets.
• Collaborate with hardware performers to validate formulations through printing trials, provide mix designs compatible with hardware constraints, and contribute to joint interface definition.
• Demonstrate successful underwater 3D printing of at least one structural element using a mix design recommended by the AI concrete formulation tool, conducted in coordination with at least one hardware track performer.
• Demonstrate successful underwater 3D printing of at least one structural element using an optimized formulation output through the AI concrete formulator. The AI tool should be developed with awareness that future iterations will move to onboard capability becoming part of feedback loops to dynamical monitor and adjust processes throughout the future harvest-to-print system.

Phase I

This topic is soliciting Direct to Phase II (DP2) proposals only. Research and development in the field of 3D concrete printing has recently demonstrated formulations utilizing wet sea floor sediments and salt water with less than 20% binder are feasible to achieve self-supporting strength and printability. Firms may propose to multiple tracks/components, but they must be part of a single proposed effort for the award limit. DARPA will not make multiple awards to a single firm for this topic.

To substantiate that a proposer’s technology can be funded directly to Hoboken Phase II, feasibility must be proven as part of the proposal through the following:

• Proposers to Tracks 1-3 must demonstrate previous work and understanding of the unique characteristics and challenges of utilizing low-binder seafloor sediment concrete mixes.
• Proposers to Track 4 must demonstrate previous work with low-binder, non-traditional concrete mixes.

Feasibility was established in the DARPA Trenton program, which demonstrated underwater printing of self-supporting arches using seafloor sediments and seawater, with less than 20% binder.

Phase II

Phase II will follow a rigorous systems engineering process, with each performer developing and demonstrating one or more critical subsystems. Full system integration is deferred to a future program. The 18-month effort is structured in four stages:

1. Feasibility and Requirements Analysis

• Refine and validate system-level and subsystem-level requirements based on operational needs, environmental constraints, and future integration goals.
• Engage with other performers and stakeholders to align requirements and interfaces for real-world applications and transition pathways.

2. System Design, Process Flow, and Detailed Design

• Develop and document subsystem architectures, process flows, and interface definitions.
• Conduct a Design Review to ensure technical feasibility, risk mitigation, and detailed design sufficient for parts procurement.

3. Component Fabrication and Subsystem Testing

• Fabricate and test individual subsystem components (printer, batching/pumping, mixing/QC, formulation).
• Demonstrate that each subsystem meets its performance requirements and is ready for future integration.

4. Prototype Demonstration and Transition Planning

• Conduct prototype demonstrations of individual subsystems in lab or relevant environments as applicable (e.g., near-shore underwater).
• Evaluate subsystem performance, interoperability, and readiness for transition.
• Develop technology transfer, commercialization, and scaling plans.

To maximize the impact and transition potential of the Hoboken program, all performers must design their subsystems for future integration with independently developed components. Each proposal must include an Integration Readiness Plan, and awardees will participate in regular cross-team Technical Interchange Meetings. Interface standards will be collaboratively defined and documented. DARPA anticipates a follow-on Strategic Breakthrough Phase II focused on full system integration, for which strong collaboration and integration readiness will be key selection criteria. Teams may submit joint proposals or letters of intent to collaborate on integration activities, which will be considered favorably in the evaluation process.

The prototype demonstration must support a real-world application in one of the following areas:

• Port damage repair
• New port construction
• Seawall construction
• Underwater cable/pipe protection
• Blowout protection for oil and gas
• Artificial reefs and reef repair

Throughout the phase, proposers must collaborate with commercial and military end-users to refine operational requirements and deployment scenarios. Integration and continued development of a completely subsea system must also be addressed before the end of the phase, including a technoeconomic analysis (TEA). The final report must include technology transfer documents outlining planned opportunities for commercial and military applications.

DP2 Base milestones for this program should include:

• Month 2: Requirements Analysis - Finalize subsystem requirements, interfaces, and integration plan with cross-team input
• Month 6: Design Review - Detailed design review, fabrication plans, and risk assessment sufficient to support parts procurement
• Month 8: Prototype Demonstration Plan
• Month 12: Heading Check - Review build progress, risks, and test plans
• Month 16: Transition Planning - Develop technology transfer, commercialization, and scaling plans
• Month 17: Prototype Demonstration - Demonstrate subsystem prototypes in near-shore, underwater environment
• Month 18: Final Reporting - Summarize results, subsystem performance, and recommendations for future integration

DP2 Base deliverables should include:

• Month 2: Requirements Specification and Interface Control Document (ICD), including permitting plan as applicable
• Month 6: Design Review Package (Technical Design Package, Bill of Materials (BOM), updated schedule, risk register, PowerPoint Presentation)
• Month 8: Prototype Demonstration Plan including location, permitting, safety, transportation, and other logistics
• Month 12: Heading Check Review Package (Test plans, Test data, Fabrication progress, Prototype Demonstration readiness, updated schedule and risk register, PowerPoint Presentation)
• Month 16: Transition Plan Report or PowerPoint including Scaling Strategy and Technoeconomic analysis (TEA)
• Month 18: Final Report: Performance Data Package and Lessons Learned Report, transition recommendations, and integration readiness

Phase III dual use applications

Successful development of the subsystems for an underwater 3D concrete printing system will have significant applications in both the military and commercial sectors:

• DoW Applications: expeditionary port damage repair, underwater infrastructure, and underwater asset protection
• Commercial Applications: offshore platform construction, custom mooring, shoreline protection, environmental restoration, hydroelectric infrastructure, and underwater data centers.

The products developed in Phase II should be ready for integration and deployment for both military and commercial use. Building on Phase II subsystem demonstrations, the vision is to achieve full system integration—combining sediment harvesting, concrete formulation, transportation, mixing, and printing into a seamless underwater 3D construction capability.

Key objectives for follow-on work include:

• Integrating subsystems from all tracks to validate end-to-end performance and real-time adaptive control.
• Advancing toward autonomous, deep-water operations with minimal topside support.
• Demonstrating the complete system in operationally relevant scenarios such as port repair, seawall construction, and underwater asset protection.
• Executing technology transfer and commercialization plans in partnership with military and commercial stakeholders.

Proposers should ensure their solutions are designed for interoperability and future integration, with clear interface definitions and readiness for cross-team collaboration. Proposals that allow for logical scope expansion or integration pivots will be best positioned for follow-on opportunities. The goal is to enable rapid, flexible, and environmentally conscious underwater construction using in situ materials and advanced automation, supporting a wide range of dual-use applications.

References

Trenton BAA: https://sam.gov/opp/d6e4081f51224e699b7d204c450c1682/view

TPOC-1-PoC

DARPA BAA Help Desk

Email

SBIR_BAA@darpa.mil

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