Recently, a client called the EMPF Helpline to get information on DMSMS and ruggedization of electronics.
Diminishing Manufacturing Sources Material Shortages (DMSMS) is defined as the loss or impending loss of manufacturers of items, suppliers of items, or raw materials. DMSMS and obsolescence are terms that are often used interchangeably. However, obsolescence refers to a lack of availability due to statutory and process changes, as well as new designs; whereas DMSMS is a lack of sources or materials.1
The Defense Standardization Program Office source has addressed the topic by publishing a guidebook that is available for downloading. The guidebook (SD-22) contains Best Practices and tools for implementing a DMSMS Management Program (Figure 2-1). There are many other formal programs offered by the DoD to deal with DMSMS and are available on the internet at the DMSMS Knowledge Sharing Portal at www.dmsms.org and other sites.
Military requirements for improvements in capability and speed for information handling electronics have increased identically to the commercial consumer’s desires and needs. However, the physical endurance requirements remain as stringent and in some cases more severe. Even though the availability of mil-spec electronics has dwindled and the cost has grown exponentially, the improved capability and endurance requirements must be achieved. Military electronic hardware has been especially hard hit by manufacturers abandoning their low volume military qualified parts.
A tool that has been used to mitigate DMSMS since the 1980s is the procurement of commercial off-the-shelf (COTS) items across the board. One drawback of this approach is the inability of these electronics to withstand military environments. Ruggedization of commercial parts and systems is an attempt to have the available COTS electronics hardened to withstand the rigorous requirements of military use, while eliminating the need for very expensive custom designs. This technique has many other benefits as well. Increased performance and capability, increased availability, and drastically decreased costs can be achieved with modern COTS electronic products.
Electronics ruggedization addresses all aspects of the intended use of the devices.
- Replacement of electronic components that do not meet the temperature range or other environmental requirements.
- Addition of heating/cooling to expand the temperature capabilities.
- Addition of any necessary vibration isolation or dampening to component packaging.
- Selection and application of conformal coating to circuit boards for moisture, salt spray, and wind driven rain protection.
- Conversion to ruggedized electrical and fluid connectors.
- Additional circuitry, if needed.
- Redesign of the chassis and housings with EMI considerations, including radiated and conductive emissions and susceptibility.
Some product specifications include a boiler plate set of military specifications that may not be appropriate for the intended platform and should be more closely scrutinized. COTS design and ruggedization efforts cannot address some of the environmental EMI/RFI extremes. A well developed Performance Specification should be generated and approved, guided by the constraints of the desired unit and its intended use before the design is realized.
The EMPF has recently completed a Navy project for ruggedizing an advanced acoustic hailing system.2 It is now being tested before deployment with the fleet. For more information about the complete design and manufacturing services for COTS development available at the EMPF, contact Ken Friedman, at 610.362.1200, extension 279 or via email at kfriedman@aciusa.org.
References
1 DOD Supply Chain Materiel Management Regulation, DoD 4140.1-R (2003).
2 Verdi, Fred. “Ruggedization of COTS Technology.” Empfasis (Oct. 2008): 1.
