Miniature Exercise Device (MED-2) - 08.23.18

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

ISS Science for Everyone

Science Objectives for Everyone
The microgravity environment of space weakens muscle and bone, so orbiting crew members spend significant amounts of time exercising. But the International Space Station’s exercise equipment is large and bulky. The Miniature Exercise Device (MED-2) demonstrates that small robotic actuators can provide motion and resistance for crew workout sessions, reducing the size and weight of exercise equipment for long-duration space missions.
Science Results for Everyone
Information Pending

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

OpNom: Miniature Exercise Device

Principal Investigator(s)
Cherice Moore, M.S., NASA Johnson Space Center, Houston, TX, United States

Information Pending

NASA Johnson Space Center, Houston, TX, United States

Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)

Sponsoring Organization
Technology Demonstration Office (TDO)

Research Benefits
Earth Benefits, Space Exploration

ISS Expedition Duration
March 2016 - August 2018

Expeditions Assigned

Previous Missions
Information Pending

^ back to top

Experiment Description

Research Overview

  • Exercise is required by crew members during spaceflight to maintain health and to counter the debilitating effects of micro gravity. The current exercise equipment used in space is very bulky. Smaller exercise devices free up room for other critical equipment for space flight.
  • The Miniature Exercise Device (MED-2) demonstrates the use of robotic technology to provide the motion and resistance needed in the device. The investigation shows that the actuator performs as predicted in the space station environment with the crew member.
  • This technology leads to the next generations of exercise equipment that is an order of magnitude lighter and smaller than existing systems.


The Miniature Exercise Device (MED-2) is a system to test key technologies needed to develop space based exercise equipment that may provide appropriate countermeasures to the adverse effects of microgravity. This technology is critical for the initial design and development of second and third generation Counter Measure Systems (CMS) hardware that is an order of magnitude lighter and smaller than existing ISS class of CMS hardware and that has significantly greater reliability.
ISS and on board crew interaction is required for this Detailed Test Objective (DTO). Current counter measure devices behave differently in the microgravity environment than in ground test as seen in both the crew interaction and sensors in the systems. To effectively evaluate the technology, an extended microgravity environment with crew interaction is required. The MED-2 is a one degree of freedom system using a robotic actuator to control the load experienced by the operation. The use of a robotic type actuator allows precise control of the load that can be varied over a variety of conditions including position and velocity of the actuator. This DTO is designed to verify that the control of the actuator with a crew member in the microgravity environment in the loop. Various modes of the actuator are assessed at various velocities. This may include constant load, progressive loads and non-linear loads based on position and/or velocity of the actuator. The performance is assessed through data collected by instrumentation on the MED-2 system as well as the perceptions of the crew member.

^ back to top


Space Applications
Crew members on long-duration missions to space must exercise regularly to avoid muscle atrophy, bone loss, changes to the cardiovascular system, and other problems. Exercise equipment will be especially important on long exploration missions, because crew members must be in excellent physical shape to explore other planets, asteroids or other distant destinations. The technology in this investigation improves exercise capability on the International Space Station (ISS), as well as future missions to near-Earth asteroids and Mars.

Earth Applications
The technology in this investigation may be applied for patients undergoing physical therapy on Earth. A robotic actuator provides resistance, which could be easily adjusted depending on a patient’s needs. Rehabilitation specialists and physical therapists would have a unique new tool to work with, enabling rehabilitation programs tailored to individual patients.

^ back to top


Operational Requirements and Protocols

The minimum requirement is to have one crew member operate the MED for 3 one hour sessions. Data from the system and crew comments on the operations will be downlink to the ground team for evaluation of the systems performance. The sessions should be spread at least 1 week apart to allow the ground team time to analyze the data and make adjustments to the control parameters and test protocols.

The crew member plugs the MED into the ISS power source (AC inverter) and Ethernet. Crew member selects the loading profile on the interface device and articulate the system. Loads and other data are recorded. The articulation is repeated for various load profiles. The crew member downlinks the recorded data along with any comments on MED operations. System is then disconnected from power and Ethernet until next use.

^ back to top

Decadal Survey Recommendations

Information Pending

^ back to top

Results/More Information

Information Pending

^ back to top

Related Websites

^ back to top


MED-2 flight shown with the rowing foot plate attachments (Tbar omitted in this image. Strap is not the flight strap).

+ View Larger Image

MED-2 Certification unit, including Tbar handle, mounted on ARED platform.

+ View Larger Image