Air force 14. 1 Small Business Innovation Research (sbir) Proposal Submission Instructions

PHASE I: Demonstrate feasibility for quantifying variation in dynamic loads due to changes in vehicle inertial properties from mission to mission. The dynamic loads include both 1) surface pressures on the air vehicle and

2) big bone/component loads such as wing root bending. This task can be accomplished with a finite element model and an aerodynamics model derived from an outer moldline.

PHASE II: Integrate the dynamic loads variational capability developed in Phase I into a relevant 6-degrees of freedom (DOF)-vehicle simulation environment. Identify critical maneuvers/flight conditions via enhanced 6-DOF simulation and application of the resulting loads spectra to the air vehicle finite element model (AV FEM). Identify critical stress regions (hot spots) within the AV FEM. Establish correlation between these global hot spots and an individual structural component damage tolerance model.

PHASE III DUAL USE APPLICATIONS: The resulting capability has applications in both 1) prototype development activities and 2) service life extension programs.

REFERENCES:

1. Eric J. Tuegel, Anthony R. Ingraffea, Thomas G. Eason, and S. Michael Spottswood, "Reengineering Aircraft Structural Life Prediction Using a Digital Twin, "International Journal of Aerospace Engineering, Vol. 2011.
2. P.C. Chen, D.H. Baldelli, and J. Zeng, "Dynamic flight simulation (DFS) tool for nonlinear flight dynamic simulation including aeroelastic effects," in Proceedings of the AIAA Atmospheric Flight Mechanics Conference and Exhibit, Honolulu, Hawaii, USA, 2008, AIAA 2008-6376.
3. E.H. Glaessgen, E. Saether, S.W. Smith, and J.D. Hochhalter, "Modeling and characterization of damage processes in metallic materials," in Proceeding of the 52nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Denver, Colorado, USA, 2011, AIAA 2011-2177.
4. H.D. Dill and C.R. Staff, "Effect of Fighter Attack Spectrum on Crack Growth," AFFDL-TR-76-112, May 1975 - July 1976.
5. H.D. Dill and C.R. Staff, "Environment - Load Interaction Effects on Crack Growth," AFFDL-TR-78-137, July 1976 - August 1978.
KEYWORDS: aircraft life prediction, aircraft usage, aircraft structural integrity program, structural dynamics, aircraft aging, aircraft loads, fatigue life, recorded flight data

AF141-067 TITLE: Structural Reliability Analysis

OBJECTIVE: The objective is to develop a structural reliability analysis calculation tool that has the capability and flexibility to correctly model the physics of the variety of possible post-inspection structural repair options.

DESCRIPTION: The current structural reliability analysis software used by the USAF models the post-inspection condition of the structure as a repair crack size distribution only. Such a model for a post-inspection repair is adequate if the repair is oversizing a fastener hole up to the second oversize. But if the repair is a doubler, or an interference fit bushing, the repair crack size distribution cannot capture the changes in the crack growth curve or maximum stresses in the part. A structural reliability analysis tool is needed that has multiple options for changing the reliability calculation inputs after an inspection. Since the type of repair performed is dependent upon the size of the crack found during the inspection, more than a single repair model is required. Furthermore, because the repair options for different airframe locations are different, the models for repairs and when they are applied needs to be flexible so that the reliability analyst can select which models to use and when they are applied. Repairs to be considered are oversizing of fastener holes and patches at a minimum.
Object-oriented modeling software, like ModelCenter or SPISE, for example, have created modeling environments in which it is possible to construct a flexible engineering analysis tool. Basic function routines can be created as modules. These modules have specified inputs and outputs. They form the building blocks for constructing an engineering model. These modules are linked together in different ways and are used over and over again in building the model.
While it seems that structural reliability analysis would lend itself to models constructed in one of these object-oriented environments, it is not clear how this can be done. The fundamental routines for structural reliability analysis need to be determined and developed into modules. Examples of two modules needed, based on routines in the current reliability analysis tools, are probability of crack detection during nondestructive inspections (NDIs) and probability of failure. The framework for how these modules should be linked together in order to perform a structural reliability analysis needs to be developed. Finally, the flexibility of this framework needs to be demonstrated for a number of different structural components. The intent of this project is not to develop an object-oriented modeling environment. It is rather to build a structural reliability analysis framework within a commercial off-the-shelf (COTS) object-oriented modeling environment. This framework must have the flexibility to accommodate the variety of possible repair scenarios and their effect on the random variables in a structural reliability analysis of fatigue in metallic structures: fracture toughness, crack size, and maximum stress during a flight.

PHASE I: Phase I will develop the basic routines needed for structural reliability analysis into reusable modules for a particular object-oriented modeling environment. These modules will be demonstrated by simulating reliability analysis for the lifetime of a single structural component.

PHASE II: Phase II will develop the ability to statistically update the prior reliability analysis for a location based upon new information such as the size of any cracks found during inspections or what repair was actually performed. This capability will be demonstrated by performing reliability analyses over the lifetime of multiple different structural components. The demonstration will take place at WPAFB. A manual describing how to use the software will be required.

PHASE III DUAL USE APPLICATIONS: Phase III applications of this reliability analysis technology include all USAF aircraft systems. Application to Army, Navy, and commercial aircraft is possible, but will require that some additional modules be developed since each organization has slightly different requirements.

REFERENCES:

1. Berens, A.P., Hovey, P.W., and Skinn, D.A., "Risk Analysis for Aging Aircraft Fleets," WL-TR-91-3066, DTIC #ADA252000, 1991.

AF141-068 TITLE: Generic Power/Propulsion Microcontroller for Unmanned Aircraft Systems (UAS)

OBJECTIVE: Develop and demonstrate a small, common controller that can efficiently control all aspects of propulsion and power management for UAS vehicles.

DESCRIPTION: The use of UASs has greatly increased over the last 12 years and these systems are assuming greater operational roles in the field, becoming force multipliers for the military. Current controls for UAS propulsion, especially small UASs, typically are simple throttle actuators. The next-generation UAS power/propulsion systems will require state-of-the-art controls to manage systems for peak performance. Next-generation propulsion and power systems are being developed to take advantage of technology development in lightweight, efficient electric propulsion, high-density power storage, advanced internal combustion (IC) and turbine concepts, and electrical systems. Technologies under development such as microfuel injection, microfuel pumps, micro-ignition systems and microturbochargers are being integrated into UAS power/propulsion systems. A combination of software and hardware will be needed to manage performance functions of the power/propulsion system. A controller is desired that can be applied to the power/propulsion system, regardless of the approach, seamlessly switching or connecting diverse propulsion modes and electrical sources with different torque, voltage, current, and impedance characteristics as needed and if needed. Concepts proposed should provide the ability to be incorporated as a hierarchical software component of the vehicle electric power, propulsion, and flight control. It is important to evaluate methodologies that enable parameter monitoring capability, system transients, and potential failure modes. Proposals must demonstrate a grasp of UAS controls issues and needs. Concepts should be well defined for both their hardware and software visions. Cost, flexibility, growth and other issues not articulated here are all capabilities that need to be explored.

PHASE I: Demonstrate the feasibility of small control systems that can handle the real-time operation of potentially complex power/propulsion systems for UAS platforms. Evaluate the potential to develop a system that handles all mission modes efficiently while minimizing transient responses, especially in flight modes.

PHASE II: Develop and refine the Phase I concept into a hardware and software prototype system. Demonstrate the system capability by conducting tests on relevant UAS power/propulsion system components to evaluate the system effectiveness. Use modern sensor and actuator technology to monitor and control energy flows and regeneration; and demonstrate management of system operations such that the system can effectively switch among individual (engine or motor) modes when applicable, etc.

PHASE III DUAL USE APPLICATIONS: Military applications include UAS platforms that employ small turbines, small internal combustion engines (ICE) and/or hybrid propulsion concept vehicles. Commercial applications would include high end UAS systems.

REFERENCES:

1. “Hybrid Engine Concept from Flight Design,” AVweb, v15n30d, July 30, 2009, (www.avweb.com/eletter/archives/avflash/1425-full.html).

AF141-070 TITLE: Lithium-Ion (Li-ion) Battery Electrolytes using Nonflammable, Room-Temperature Ionic

Liquids
KEY TECHNOLOGY AREA(S): Air Platforms
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 section 5.4.c.(8) of the solicitation and within the AF Component-specific instructions. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. Please direct questions to the AF SBIR/STTR Contracting Officer, Ms. Kristina Croake, kristina.croake@us.af.mil.

OBJECTIVE: The purpose of this effort is to develop an ionic liquid based electrolyte for lithium-ion batteries that is nonflammable, has a high ionic conductivity over a wide temperature range, and is electrochemically stable to ensure long battery lifetimes.

DESCRIPTION: Rechargeable Li-ion batteries can fail violently when subjected to an internal electrical short, are overheated, crushed, or when then are overcharged/overdischarged. Recent events such as the grounding of a commercial aircraft due to Li-ion battery fires demonstrate that the safety of Li-ion batteries is of major concern. Of particular interest are improvements in safety for Li-ion batteries with the use of electrolytes based on nonflammable, room temperature ionic liquids. These new batteries will demonstrate improved safety under various abuse/extreme conditions while also increasing the battery performance at military relevant operating temperatures (-40 to +75 degrees C), storage temperatures (-55 to +85 degrees C), and at high charge/discharge rates (capable of charging/discharging at greater than a 20C rate). These innovative solutions should also place an emphasis on reducing the acquisition costs of these alternative batteries to levels that will make them cost competitive with existing Li-ion, lead-acid, and nickel-cadmium military batteries in terms of acquisition and life cycle.
During Phase II, the offeror will produce a prototype battery for a chosen Air Force (AF) application that involves aircraft emergency and pulse power using the advanced electrolytes. The offeror will also compare the performance to the baseline battery system. The Phase II prototype should be delivered to the AF for additional testing and evaluation. At the end of the contract, the offeror should also demonstrate the prototype at Wright-Patterson AFB to outbrief technology advancements.

PHASE I: Propose an innovative nonflammable electrolyte based on room temperature ionic liquids for rechargeable Li-ion batteries. Li-ion batteries will have equivalent or better energy and power density capability in relation to current high-rate Li-ion technology. Present experimental and other data to demonstrate feasibility of innovative solution. Prepare initial transition plan.

PHASE II: Produce an alternative safer Li-ion battery using the developed nonflammable electrolytes for use in an Air Force aircraft emergency and pulse power application (TBD during Phase I). The prototype battery or module size will also be determined during Phase I. Provide cost projection data to substantiate the design, performance, operational range, acquisition, and life cycle costs. Refine transition plan and business case analysis.

PHASE III DUAL USE APPLICATIONS: The military applications include aircraft emergency and pulse power, electric tracked vehicles, unmanned systems, hybrid military vehicles, and unmanned underwater vehicles (UUVs). Commercial applications include hybrid and electric vehicles, portable electric drills, etc.

REFERENCES:

1. Matsui, Y., Kawaguchi, S., Sugimoto, T., Kikuta, M., Higashizaki, T., Kono, M., Yamagata, M., and Ishikawa, M., "Charge-Discharge Characteristics of a LiNi1/3Mn1/3Co1/3O2 Cathode in FSI-based Ionic Liquids," Electrochemistry, Vol. 80 (2012) pp. 808-811.

AF141-071 TITLE: Safe, Large-Format Lithium-Ion (Li-ion) Batteries for Aircraft

OBJECTIVE: The purpose of this effort is to develop safe, large-format aircraft Li-ion batteries where propagation of a cell failure is minimized.

DESCRIPTION: Rechargeable Li-ion batteries can fail violently when subjected to an internal electrical short, are overheated, crushed, or when then are overcharged/overdischarged. Recent events such as the grounding of a commercial aircraft due to Li-ion battery fires demonstrate that the safety of Li-ion batteries is of major concern. Of particular interest are improvements in safety for large-format aircraft Li-ion batteries by eliminating cell-to-cell thermal transport and cell failure propagation. These new batteries will demonstrate improved safety under various abuse/extreme conditions while also increasing the battery performance at military relevant operating temperatures (-40 to +75 degrees C), storage temperatures (-55 to +85 degrees C), and at high charge/discharge rates (capable of charging/discharging at greater than 20C rate). These innovative solutions should also place an emphasis on reducing the acquisition costs of these alternative batteries to levels that will make them cost competitive with existing Li-ion, lead-acid, and nickel-cadmium military batteries in terms of acquisition and life cycle.
During Phase II, the offeror will produce a prototype battery for a chosen Air Force (AF) application that involves aircraft emergency and pulse power using the advanced configuration. The offeror will also compare the performance to the baseline battery system. The Phase II prototype should be delivered to the AF for additional testing and evaluation. At the end of the contract, the offeror should also demonstrate the prototype at Wright-Patterson AFB to outbrief technology advancements.

PHASE I: Develop an innovative, safe, large-format rechargeable aircraft Li-ion battery that does not have cell-to-cell propagation of a cell failure. Li-ion batteries will have equivalent/better energy/power density capability relative to current high rate Li-ion technology. Present experimental and other data to demonstrate feasibility of proposed solution. Develop initial transition plan.

PHASE II: Produce alternative, safer Li-ion battery using the developed configuration for AF aircraft emergency/pulse power application (TBD during Phase I). The prototype battery/module size will be determined during Phase I. Provide cost projection data substantiating the design, performance, operational range, acquisition, and life cycle cost. Refine transition plan and business case analysis.

PHASE III DUAL USE APPLICATIONS: The military applications include aircraft emergency and pulse power, electric tracked vehicles, unmanned systems, hybrid military vehicles, and unmanned underwater vehicles (UUVs). Commercial applications include hybrid and electric vehicles.

REFERENCES:

1. Kim, G.H., Smith, K., Ireland, J., and Pesaran, A., "Fail-safe design for large capacity lithium-ion battery systems," J. Power Sources, Vol. 210 (2012) pp. 243-253.

AF141-072 TITLE: Fiber-Optic-Distributed Temperature Sensing System

OBJECTIVE: Develop a fiber-optic-distributed sensor system that will sense bleed air leaks in the propulsion, environmental control, and thermal management systems (TMSs) to increase survivability throughout the operating mission of advanced tactical aircraft.