Jul
01
2009

If you wanted to explore Mars, what kind of bridge would you take with you? How would you build the bridges? How would you make sure the bridge will work for a variety of terrain? Since you must carry the bridge all the way to Mars, it must be small, light, and highly reliable. Researchers from the Technical University of Munich have a wonderful answer: a tensegrity truss.

BRIDGING MARS from Zoran Novacki on Vimeo.

Tensegrity masts are also used for deploying a variety of instrumentation and solar panels on orbiting satellites. The tensile network is bearing the weight of the structure; by increasing the tension, the mast deploys. It’s a remarkably material-efficient way to “reach out” with structure. Tensegrity masts can even teach us how to reach out more effectively with our arms and legs.

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Feb
03
2009

Computer programming has changed tremendously over the last two decades, but some ideas have stood the test of time. In Object Oriented Analysis and Design, first published in 1990, software architect Grady Booch noted:

“Modularity is the property of a system that has been decomposed into a set of cohesive and loosely coupled modules.”

Today, Booch’s ideas of loosely coupled design are embraced by programmers world-wide. In well-designed computer programs, each module does a small number of things well. There are specific and well-defined ways that a module talks with other modules. Modules are functionally independent; changes to one module will not affect other modules.

Contrast this with a tightly coupled machine. Parts in a tightly coupled machine are designed to run “like clockwork”. All the parts move in lock-step with each other.

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A 19th century orrery: a model of our solar system with all its parts moving “like clockwork”.

There are problems designing programs with a tightly coupled design:

• The modules are large or everything is in one huge module.

• Changes to one module can change the behavior of other modules in unpredictable and undesired ways.

• As the computer program grows, it becomes increasingly difficult or impossible to have it behave correctly.

Our musculoskeletal structure is loosely coupled. Our bones don’t touch; there are no levers or fulcrums. We’re designed to move in a smooth and flowing fashion; we don’t move like a clock or any other tightly coupled machine.

If we are loosely coupled, why don’t we consistently move that way? And what does this have to do with Feldenkrais?

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