N241-049 TITLE: Shipboard Proof Testing Apparatus for Field-Expedient Parts

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Advanced Materials

OBJECTIVE: Develop testing equipment for the shipboard environment to enable proof testing of field-expedient parts fabricated in the shipboard environment.

DESCRIPTION: Navy ship platforms are currently outfitted with varying capability for on-board machining, repairs, and fabrication, to include additive manufacturing (AM). With the deployment of AM expanding to the shipboard environment, the manufacturing capability of more complex items are becoming more readily available to the Fleet. With this addition in capability, there is an increased risk of potential inadequate parts being installed in ship systems. There is a need to be able to reduce the risk of installing field-expedient parts designed by the Fleet. Part of this risk reduction can be achieved through proof testing of the designed parts at the point-of-need. This capability would allow shipboard leadership to make a more informed, rapid risk assessment of part viability based on empirical test data from the desired solution.

There are increased needs for AM afloat as it is explicitly identified in the COMNAVSEA Campaign Plan 3.0 as a technology focus area. The Navy directly supports efforts to integrate AM into the Fleet and support a more self-sufficient ship. The Navy seeks to maximize its use of AM to fabricate "hard to source" or obsolete parts, reduce cost, field more effective systems, and reduce reliance on vulnerable supply chains through production at the point of need.

The goal of this project will be to develop a modular proof testing apparatus for locally manufactured components in the shipboard environment. The solution must include the ability to test non-uniform objects, tools, and parts which should be able to be mounted and tested within the same test unit. In addition, different loading conditions and scenarios must be able to be applied to the test part within this apparatus. Example loading scenarios include, but are not limited to: tensile, compression, torque and pressure. The operational conditions within these expeditionary settings include ship motion, ship vibration, shock, ventilation, and electromagnetic interference (EMI). In order to successfully install the test rig and enable adequate operation of the equipment, the machine must not experience severely degraded performance under these conditions. All processing must be completed on the system and must operate in a non-networked environment. Sensor packages supporting tracking of system operation and performance, as well as machinery health monitoring, should be included in the design.

Current test apparatuses of this nature are specialized laboratory equipment that is not designed for use in the dynamic shipboard environment. In addition, current commercial tensile, compression, torsion, and pressure testing systems require a degree of training for interpretation of data that is not feasible for the typical Navy operator. There exist no commercial solutions that can provide easy-to-assess part test responses that allow for rapid risk reduction. Furthermore, simplistic design and usability will be beneficial since most Fleet personnel will not have an engineering or science background. This should include ease of use from a test setup and operation standpoint, but also clear, definitive, and easy to understand results display and interpretation. The designed solution should have on board processing capability, with full traceability and logs available. These systems must include a modular test fixture and load application design to be able to accommodate the variability in types of parts being 3D printed. In addition, since both metal and polymer solutions are being deployed, the solution should be able to accommodate forces necessary for both material types, including, but not limited to, carbon fiber reinforced nylon and 316L stainless steel. The solution should be able to test parts that fit within a 20" Wide x 12" Deep x 12" High volume. The system itself should be hatchable, and take special consideration to minimize footprint of the design. The aforementioned design considerations to overcome the technological gap is paramount as a risk reduction method to enable the Fleet to safely install AM solutions shipboard.

The product will be assessed against the MIL-STDs listed below:

1. MIL-S-901D, Amended with Interim Change #2, Shock Test, H.I. (High Impact); Shipboard Machinery, Equipment and Systems, Requirements for

2. MIL-STD-167-1, Mechanical Vibration for Shipboard Equipment (Type I - Environmental and Type II - Internally Excited)

3. MIL-STD-461F, Requirements for the Control of Electromagnetic Interference Characteristics of Subsystems and Equipment

4. MIL-STD-740-2, Structure-borne Vibration Acceleration Measurements and Acceptance Criteria of Shipboard Equipment

PHASE I: Develop a conceptual design of a modular proof testing apparatus that can test shipboard manufactured parts, including Additively Manufactured items as described in the Description section. Demonstrate the feasibility of the conceptual design through detailed modelling, simulation, and analysis for the proposed solution. For example, 3D models, simulations, and/or design documentation to illustrate the work holding/fixturing modularity option to accommodate the various types of applications and loading scenarios. The conceptual design feasibility analyses should also indicate how the apparatus will be hardened for the shipboard environment to be able to accurately apply loads, but also handle the dynamic shipboard environment. Include, in the conceptual design applicable sensors and details on how the machine will be optimized for Fleet use, to include, but not be limited to, operation, maintenance, and results display. The design details should include the on-board processing setup and the proposed results reporting display.

The Phase I Option, if exercised, will include the initial design specifications and capabilities description to build a prototype solution in Phase II.

PHASE II: Build and deliver a prototype system that can apply proof testing loads to sample parts that can be operated in the shipboard environment by shipboard personnel. Demonstrate how shipboard environmental mitigation will be applied to account for incoming vibration and shock, and uncontrolled temperature and humidity. Subsequent testing of these mitigation protocols will be needed to evaluate shipboard viability and should be included. Examples of the simplified setup and results should be included in the prototype, with processing occurring local to the proposed solution. The prototype is expected to be installed either shipboard or at a Navy facility for continuation testing and evaluation.

PHASE III DUAL USE APPLICATIONS: Assist the Navy to transition a production ready proof testing machinery optimized for Navy expeditionary environments with modular options for tensile, compression, torque, and mechanical pressure loading applications. The equipment must be able to operate in the shipboard environment (machine shop or welding spaces) and be able to accurately apply loading conditions for various, non-uniform applications of multiple material types including, but not limited to, chopped carbon fiber filled Nylon and 316L Stainless Steel. The solution must be able to simply interpret results to inform a risk-based decision-making analysis for Fleet personnel. All processing must be completed on board the system and must operate in a non-networked environment.

The applicability of such a design could be implemented in environments beyond just the shipboard community, to include the local maintenance activities and Shipyards. In addition, commercial applications of the solution for the shipping or oil and gas industry and other Military forward operating bases may be available.

REFERENCES:

1. Amend, JR, Jr., & Lipson, H. "FreeLoader: An Open Source Universal Testing Machine for High-Throughput Experimentation." Proceedings of the ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering
2. United States, Congress, Office of the Under Secretary of Defense for Research and Engineering. DOD Additive Manufacturing Strategy, January 2021.https://www.cto.mil/wp-content/uploads/2021/01/dod-additive-manufacturing-strategy.pdf

KEYWORDS: Metal additive manufacturing; 3D printing; Shipboard Additive Manufacturing; Proof testing; Shipboard Validation Testing; Testing of AM manufactured parts; Mechanical part testing

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