[FPSPACE] MIT models interplanetary supply chain

[LARRY KLAES]

MIT models interplanetary supply chain

For Immediate Release

THURSDAY, MAR. 22, 2007

PHOTO, GRAPHICS AVAILABLE  - Contact:

Elizabeth A. Thomson, MIT News Office

Phone: 1-617-258-5402

Email: thomson at mit.edu

CAMBRIDGE, Mass.--If you think shipping freight from Cincinnati to El Paso 
is challenging, imagine trying to deliver an oxygen generation unit from the 
Earth to a remote location on the moon.

By 2020, NASA plans to establish a long-term human presence on the moon, 
potentially centered on an outpost to be built at the rim of the Shackleton 
crater near the lunar South Pole.

To make such a scenario possible, a reliable stream of consumables such as 
fuel, food and oxygen, spare parts and exploration equipment would have to 
make its way from the Earth to the moon as predictably as any Earth-based 
delivery system.  Or more predictably: One missed shipment could have 
devastating consequences when you can't easily replenish essential supplies.

To figure out how to do that, MIT researchers Olivier L. de Weck, associate 
professor of aeronautics and astronautics and engineering systems, and David 
Simchi-Levi, professor of engineering systems and civil and environmental 
engineering, created SpaceNet, a software tool for modeling interplanetary 
supply chains. The latest version, SpaceNet 1.3, was released this month.

The system is based on a network of nodes on planetary surfaces, in stable 
orbits around the Earth, the moon or Mars, or at well-defined points in 
space where the gravitational force between the two bodies (in this case, 
the Earth and the moon) cancel each other out. These nodes act as a source, 
point of consumption or transfer point for space exploration logistics.

"Increasingly, there is a realization that crewed space missions such as the 
International Space Station or the buildup of a lunar outpost should not be 
treated as isolated missions, but rather as an integrated supply chain," 
said de Weck. The International Space Station already relies on periodic 
visits by the space shuttle and automated, unpiloted Russian Progress 
re-supply vehicles.

While "supply chain" usually refers to the flow of goods and materials in 
and out of manufacturing facilities, distribution centers and retail stores, 
de Weck said that a well-designed interplanetary supply chain would operate 
on much the same principles, with certain complicating factors. 
Transportation delays could be significant-as much as six to nine months in 
the case of Mars-and shipping capacity will be very limited. This will 
require mission planners to make difficult trade-offs between competing 
demands for different types of supplies.

A reliable supply chain will "improve exploration capability and the quality 
of scientific results from the missions while minimizing transportation 
costs and reducing risks" to crew members, de Weck said.

SpaceNet evaluates the capability of vehicles to carry pressurized and 
unpressurized  cargo; it simulates the flow of vehicles, crew and supply 
items through the trajectories of a space supply network, taking into 
account how much fuel and time are needed for single-sortie missions as well 
as multiyear campaigns in which an element or cargo shipment might have to 
be prepositioned by one set of vehicles or crew members while being used by 
another.

In addition to determining a logical route, SpaceNet also allows mission 
architects, planners, systems engineers and logisticians to focus on what 
will be needed to support crewed exploration missions.

To experience an environment as close as possible to harsh planetary 
conditions, MIT conducted an expedition to Devon Island in the Canadian 
arctic in 2005. The researchers established a semi-permanent shelter at the 
existing NASA-sponsored Haughton-Mars Research Station (www.marsonearth.org) 
and compiled an inventory of materials at the base, including key items such 
as food, fuel, tools and scientific equipment, while carefully tracking 
inbound and outbound flights.

They also experimented with modern logistics technologies, such as radio 
frequency identification, that autonomously manage and track assets with the 
goal of creating a "smart exploration base" that could increase safety and 
save astronauts and explorers precious time.
SpaceNet 1.3 is written in MATLAB, a high-level technical computing language 
and interactive environment for algorithm development, data visualization, 
data analysis and numerical computation.

The SpaceNet development team includes MIT graduate students, postdoctoral 
associates and research staff led by de Weck and Simchi-Levi, aided by 
partners at Caltech's Jet Propulsion Laboratory; Payload Systems Inc., which 
provides science and engineering services for spaceflight applications; and 
NASA industry partner United Space Alliance.

For more information on SpaceNet 1.3, go to spacelogistics.mit.edu.

This work was funded by NASA.