The Development of On-Demand Sample Return Capability (SPQR) (TechEdSat-4) - 01.16.19

Overview | Description | Applications | Operations | Results | Publications | Imagery

ISS Science for Everyone

Science Objectives for Everyone
The Development of On-Demand Sample Return Capability (SPQR) (TechEdSat-4) assists in the development of a unique, drag-based de-orbit system based on the ‘Exo-Brake.’  This permits a non-propulsive means of achieving the change in velocity (v) required for a normal de-orbit (propulsive systems, even cold-gas, can introduce crew hazards inside the International Space Station).  If successful, including the series avionics/navigation tests, small samples may be routinely returned from orbital platforms.  In addition, this series effort provides technology development opportunity for interplanetary nano-satellites, and in particular – small ‘companion’ missions to the Martian surface.  The current launch, TES-4, focuses on the next development steps for the Exo-Brake and the critical (and unique) Command/Control systems. 
Science Results for Everyone
Information Pending

The following content was provided by Marcus S. Murbach, and is maintained in a database by the ISS Program Science Office.
Experiment Details


Principal Investigator(s)
Marcus S. Murbach, NASA Ames Research Center, Moffett Field, CA, United States

Periklis E. Papadopoulos, San Jose State University, San Jose, CA, United States

NASA Ames Research Center, Moffett Field, CA, United States
San Jose State University, San Jose, CA, United States
University of Idaho, Moscow, ID, United States

Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)

Sponsoring Organization
Technology Demonstration Office (TDO)

Research Benefits
Information Pending

ISS Expedition Duration
March 2014 - March 2015

Expeditions Assigned

Previous Missions
Information Pending

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Experiment Description

Research Overview

  • The Development of On-Demand Sample Return Capability (SPQR/TechEdSat-4) studies unique research in free molecular flow drag devices – or ‘ping-pong’ flow since the air molecules are at such low density – just random particles hitting the front surface of the device in the Earth’s Thermosphere.
  • TechEdSat-4 further develops and tests a small scale Exo-Brake and related avionics/navigation systems.
  • TechEdSat-4 and related work enable the routine return of samples from orbital platforms - including the International Space Station (ISS).

The proposed Small Payload Quick Return SPQR (SPQR) project provides a means of returning small payloads in a temperature and pressure controlled environment - from the International Space Station (ISS).  The current 3U cubesat experiment, the TechEdSat-4, is the next development step in the series.  TechEdSat-4 is deployed from the JEM Small Satellite Orbital Deployer (J-SSOD) in the same fashion as the successful TechEdSat-3P that was jettisoned previously.  The principal objectives are to further develop the tension-based drag device (an 'Exo-Brake') and demonstrate frequent uplink/downlink control capability.  The current experiment is sized at a scale of .3 m, which would permit re-entry within 6 weeks (at a ~ 9 kg/m2).  Understanding the thermophysics of such a device would eventually permit it to be scaled for larger payloads and re-entry within 1.5 days.  Secondary objectives include the further development of the avionics suite, which eventually includes redundant GPS - Iridium modules which periodically update positional/altitude information which assist in the eventual guidance/targeting of the larger SPQR units.  As with the precursors TechEdSat and TechEdSat-3P, TechEdSat-4 is designed from the onset with important safety features, including two-fault tolerant critical safety attributes (in particular, use of redundant 'ALI'  - Auxiliary Lateral Inhibit switches, which prevent early electrical/RF activation -as well as inhibits for any jettison anomalies).  This is a joint effort with the San Jose State University (California State University system) and the University of Idaho, permitting extensive student engineering and development participation.

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Space Applications
The larger SPQR effort (of which the TechEdSat series represent incremental steps) leads to unique de-orbit and re-entry systems.  These systems enhance the capability for sample return from  low Earth orbit.  In addition, one of the proposed re-entry technologies required in the next test phase would enable small Mars surface missions based on the nano-satellite technologies being developed in parallel.

Earth Applications
The TechEdSat investigation helps to provide more detailed information on the atmospheric structure of the thermosphere by comparing and helping to refine models based on the de-orbit experiment data.  In addition, exploring the ability to return samples quickly and independently of return vehicles permits prompt analysis, results, and publications of on-orbit investigations for researchers.

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Operational Requirements and Protocols

TechEdSat-4 deploys from the Nanoracks CubeSat Deployer (NRCSD) attached to the JEM Remote Manipulator System (JEMRMS). 

TechEdSat-4 is part of a 48U NanoRacks NRCSD payload on the JEM MPEP (Multi-Purpose Experiment Platform) pallet.  The TES-4 multiple deployment switches are turned on only after the satellite is ejected from the J-SSOD in order to prevent inadvertent satellite appendage deployment within the J-SSOD. 

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Decadal Survey Recommendations

Information Pending

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Results/More Information

Information Pending

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Related Websites
ABC News

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The J-SSOD CubeSat deployer ejects the TechEdSat-3P (3-cubesat unit). The satellites can be deployed from the Japanese Experiment Module Kibo. The TechEdSat-4 is jettisoned using the
recently developed NanoRacks CubeSat Deployer, or NRCSD.  (NASA Image)

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image NASA Image: ISS042E296561 - Satellites TechEdSat-4 are shown successfully being launched from Nanoracks CubeSat Deployer.
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TechEdSAT-4 is the second development flight test of an Exo-Brake passive de-orbit system. The nano-satellite is a triple cubesat (3U) with a set of dual advanced avionics systems powered by the previous core power system.  This flight focuses on uplink command capability, which sets the stage for fine control of the Exo-Brake (drag-modulation) in a subsequent flight. 

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