The Component Repair Experiment -1, SDTO 17012U (CRE-1) is an incremental step toward providing an electronics repair capability during future long-duration space missions. Implementation of repair capabilities can help reduce the burden of replacement hardware. Specifically, CRE-1 demonstrates the physical steps of component-level electronics repair conducted by crewmembers aboard the International Space Station (ISS). These physical processes all 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). Therefore, the repair processes must be demonstrated in a relevant environment as part of a repair capability development.Principal Investigator(s)
ZIN Technologies Incorporated, Cleveland, OH, United States
Arctic Slopes Research Corporation, Cleveland, OH, United States
National Center for Space Exploration Research, Cleveland, OH, United States
National Aeronautics and Space Administration (NASA)Sponsoring Organization
Human Exploration and Operations Mission Directorate (HEOMD)Research Benefits
Information PendingISS Expedition Duration
October 2008 - April 2009Expeditions Assigned
18Previous ISS Missions
The predecessor to CRE-1, Soldering in Reduced Gravity Experiment, SDTO 17003U (SoRGE) was operated on the ISS during Expedition 14.
During Component Repair Experiment -1, SDTO 17012U (CRE-1), a crewmember removed and replaced components on a circuit card. The components included through-hole technology and more modern surface mount devices including both standard and fine-pitched leads. The repair steps included conformal coating removal, component removal, circuit board preparation, and component replacement. The crew was led through these tasks using detailed illustrated procedures and a training video, in much the same way that a future crew might be guided through an unplanned, emergency repair.
The CRE-1 provides a tool kit to augment existing ISS hardware which included a Maintenance Work Area (MWA) and Soldering Kit. The tool kit included a fiberglass stick and a dental pick to remove conformal coating. Both standard and fine tip cutters were included to allow for cutting away the old components (although some components were removed non-destructively). To assist in manipulating small parts, the kit included curved, straight, and reverse tweezers. Finally, additional soldering equipment was provided which included both 1/8? and 1/32? soldering iron tips, solder wick, no-clean flux cored solder wire, and liquid flux.
The circuit boards are scheduled to be returned to Earth aboard the Space Shuttle Discovery (Flight 15A) for analysis which includes a visual inspection of the repaired components, functional test of the circuit cards, crew debrief, and an evaluation of processes and tools used in the experiment. Additionally, select solder joints will be examined using Computerized Tomography (CT) X-ray scanning techniques to quantitatively determine the void fraction in the repaired joints. The analysis and evaluation will lead to a recommendation to the ISS and Constellation programs for an electronics repair tool kit that will enable future component-level repairs during long-duration space missions.
The current strategy for electronics' repair aboard the ISS calls for replacement of failed hardware which relies on spares provided by resupply flights from Earth. For future exploration missions beyond low Earth orbit, this logistical support will be much more constrained. 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 serve as a test bed for future operations as well as offer additional options for actual contingency maintenance. Before such a strategy can be adopted, data must be gathered about the practicality of performing such repairs in microgravity. CRE-1 serves to advance the state of knowledge and experience involved in manual 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.
CRE-1 conducted operations in the ISS MWA Containment Area, 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 316 degrees C (600 degrees F), using newer soldering tips included as part of the CRE-1 tool kit. An ISS video camera captured video of a majority of the repair process including the removal of conformal coatings, component removal and board preparation, and installation of the new component. During CRE-1 operations, crewmembers took detailed still imagery between key steps of the repair process for evaluation by ground-team members.Operational Protocols
Crewmembers set up the MWA, installed the CRE-1 hardware inside the MWA, and positioned the ISS video camera to capture video of the repair operations. Crewmembers then repaired a series of components on each of several circuit boards. Completion of the end-to-end repair of one component on one board constituted one experimental session. In some cases, the crewmembers worked repair steps for multiple components simultaneously (e.g. removal of conformal coating for all the components to be repaired on a single board). Sessions were not continuous and crewmembers suspended and restarted repair operations as their timeline permitted. The MWA remained deployed for the entire experiment. Upon conclusion of the experiment, the crewmembers cleaned up and stowed the MWA. Results of this experiment will be used to guide electronic repair strategies for future space missions.
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