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Component-Level Electronics-Assembly Repair (CLEAR)
08.22.08

Overview | Description | Applications | Operations | Results | Publications | Images

Experiment/Payload Overview

Brief Summary

Future long-duration exploration missions will face severe constraints on upmass and volume. Implementation of repair capabilities during these future missions can help reduce the logistical burden of replacement hardware. The Component-Level Electronics-Assembly Repair (CLEAR) Station Development Test Objective (SDTO) experiment addresses this need by developing and demonstrating the physical steps that can be manually performed in the electronics repair process, aboard the International Space Station (ISS). These physical processes all have direct or indirect dependence on gravity, and therefore must be demonstrated in a relevant environment.

Principal Investigator

  • Peter M. Struk, Ph.D., Glenn Research Center, Cleveland, OH
  • Richard D. Pettegrew, Ph.D., National Center for Space Exploration Research, Cleveland, OH

    • Co-Investigator(s)/Collaborator(s)

    Information Pending

    Payload Developer


    Glenn Research Center, Cleveland, OH
    National Center for Space Exploration Research, Cleveland, OH
    Zin Technologies, Cleveland, OH

    Sponsoring Agency

    National Aeronautics and Space Administration (NASA)

    Expeditions Assigned

    Information Pending

    Previous ISS Missions

    The predecessor to CLEAR, SoRGE was operated on the ISS during Expedition 14.

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    Experiment/Payload Description

    Research Summary

    • The physical steps in the process of manually performing electronics repair need to be demonstrated in the relevant microgravity environment of space. These steps may have a direct gravitational dependence (such as the soldering process itself) or an indirect, operational dependence on the gravity environment (such as placing, aligning, and securing small replacement parts).


    • Testing of soldering in simulated microgravity (aboard the reduced gravity aircraft) and microgravity showed significant increases in void defect formation within the solder joint. Such defects can reduce solder joint strength and thus long-term reliability. For future long-duration space missions where soldering may be required for electronics' repair, techniques for mitigating void formations must be tested on practical electronics configurations. An experiment currently on-orbit, (Soldering in Reduced Gravity Experiment) SoRGE, is examining such void mitigation strategies. Lessons learned from this experiment (as well as previous reduced gravity aircraft testing) will help guide CLEAR.


    • Determination must be made regarding what component types and sizes are amenable to manual repair techniques in a microgravity environment, by a minimally-trained repair operator. CLEAR will help determine this, by providing a range of component types and sizes on which repairs will be attempted.

    Description

    The development of a component-level electronics repair capability holds the promise of reducing the upmass and volume of spare orbital replacement units (ORU) needed to support both the International Space Station, and future long-duration manned missions. The value of reducing that upmass is evident, considering the high cost of launching hardware, and the probable reduction in logistics flight opportunities, once the Space Shuttle is retired. Given this, NASA has the need to validate the concept of component-level electronic repairs in an operational environment and to help determine what the boundaries of that capability are, in terms of the types and sizes of elements that can be repaired, the tools and infrastructure needed to support those repairs, and the training and skill levels needed for the crew to successfully conduct such repairs.

    CLEAR supports this goal by demonstrating all of the physical repair steps in manually operated electronics repairs (not including diagnostics, which can be developed and validated in a normal gravity environment). This experiment entails several functional electronic boards, with a range of component types and sizes, on which the crew will attempt conformal coating removal (and subsequent replacement), component removal, board preparation, and component replacement. The crew will be led through these tasks using detailed, illustrated procedures, and a detailed training video, in much the same way that a future crew might be guided through an unplanned, emergency repair. The results from these efforts will give researchers insight into relevant issues such as the feasibility of conducting such manually performed repairs, the sizes and types of components that can be repaired, and the tools and training that are required. These tests will also provide information on the effectiveness of void-mitigation techniques on this range of components (learned and developed in previous reduced-gravity aircraft studies, and a previous SDTO flight experiment), which has important implications on the long-term reliability of the repaired systems. This data will be gathered using postflight, Computerized Tomography (CT) X-ray scanning techniques to quantitatively determine the void fraction in the repaired joints.

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    Applications

    Space Applications

    The current strategy for electronics' repair aboard the ISS calls for replacement of Orbital Replacement Units (ORUs), which relies on re-supply flights from Earth to provide the replacement units. This logistical support may not be easily available for future exploration missions beyond low-earth orbit. Repairing electronics at the lowest component level could potentially ease the logistical burden by minimizing the upmass and volume of required spares. Implementation of such a strategy on the ISS could likewise help reduce the logistical support required for its maintenance and operations. Before such a strategy can be adopted, data must be gathered about the practicality of performing such repairs in microgravity. This experiment serves to advance the state of knowledge and experience involving manually performed, component-level electronics repair by demonstrating such repairs in an operational environment.

    Earth Applications

    Development of improved toolsets, procedures and training methods can help enable in-the-field repairs by deployed U.S. military forces, thereby assisting in reducing the logistical support requirements of U.S. forces.

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    Operations

    Operational Requirements

    CLEAR is planned to be conducted in the ISS MWA, which serves to contain any contaminants created during the electronics repair process. The soldering iron (already on board the ISS), uses a rechargeable battery and can heat up to 371 degrees C (700 degrees F), using soldering tips included as part of the CLEAR test kit. The ISS video camera will be positioned to captue video of the repair process, including the removal (and later re-application) of conformal coatings, component removal and board preparation, and installation of the new component. After the repair process is complete, the samples and video will be stowed on the ISS and returned to Earth for detailed examination and analysis.

    Operational Protocols

    For CLEAR operations, crewmembers will set up the MWA, install the CLEAR hardware inside the MWA, and position the ISS video camera to capture video of the repair operations. Crewmembers will then repair a series of components on each of several circuit boards. There are three different types of test boards, embodying three different implementations of conformal coating (one uncoated board, one coated using primer and a thin RTV silicone coating, and one unprimed with a thick RTV silicone coating). Each board contains identical circuitry and components. Completion of the end-to-end repair of one component on one board constitutes one experimental session. After completing a session, the crewmember may continue with additional sessions, or may suspend operations and continue at a later time. A practice board is provided, so that the crewmember may, at their discretion, practice on an identical component before attempting the repair on a test sample. Upon conclusion of the session (or the entire experiment), the crewmember will clean up and stow the MWA. Results of this experiment will be used to guide electronic repair strategies for future space missions.

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    Results/More Information

    Information Pending

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    Related Web Sites
  • Advanced Capabilities Project Office - Component-Level Electronics-Assembly Repair

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    Publications

    Results Publications

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      Related Publications
      • Pettegrew RD, Struk PM, Watson JK, Haylett RD. Experimental Methods in Reduced-Gravity Soldering Research. NASA TM. ;2002-211993. 2002
      • Pettegrew RD, Struk PM, Watson JK, Haylett DR, Downs RS. Gravitational Effects on Solder Joints. Welding Journal , Oct.;82 (10): 44-48. 2003
      • Struk PM, Pettegrew RD, Downs RS, Watson JK. The Effects of an Unsteady Reduced Gravity Environment on the Soldering Process. 42nd AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV. , Jan.; AIAA Paper 2004-1311 and NASA TM-2004-212946. 2004
      • Grugel RN, Cotton LJ, Segre PN, Ogle JA, Funkhouser FP, Murphy L, Gillies D, Hua F, Anilkumar AV. The In-Space Soldering Investigation (ISSI): Melting and Solidification Experiments Aboard the International Space Station. 44th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV. ,Jan.; AIAA Paper 2006-521. 2006
      • Pettegrew RD, Struk PM, Oeftering RC, Easton JW, Gorecki GE, Truong DK. Repair of Electronics for Long Duration Spaceflight. 45th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV. , Jan; AIAA Paper 2007-1364. 2007
      • Pettegrew RD, Struk PM. Overview of the Manual Electronics Repair Project Under the Supportability Program. 45th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV , Jan.; AIAA Paper 2007-0545. 2007
      • Watson JK, Struk PM, Pettegrew RD, Downs RS. Experimental Investigation of Solder Joint Defect Formation and Mitigation in Reduced-Gravity Environments. Journal of Spacecraft and Rockets. ,Jan-Feb ;44(1): 174-182. 2007
      • Pettegrew RD, Easton J, Struk PM, Anderson E. In-Flight Manual Electronics Repair for Deep-Space Missions. IEEE Aerospace Conference, ;IEEE 2007-1208. 2007

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      Images

      imageX-ray image of leads on a surface-mount component (gull-wing configuration) soldered in reduced gravity, showing internal void defects. Image courtesy of Glenn Research Center.
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      imageResearchers conducting solder testing aboard the reduced gravity research aircraft. Image courtesy of Glenn Research Center.
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      Information Provided and Updated by the ISS Program Scientist's Office
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