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Mechanical Engineering. 2009;131(09):26-31. doi:10.1115/1.2009-SEP-1.
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This article discusses how some young engineers, fabricators, machinists, artists, and plumbers are helping revive old steam engines for art and archaeology's sake. The volunteers at Kinetic Steam Works labor to recondition steam engines that will power kinetic artistic installations. Since its inception, the collective has restored a steamship and sent it down the Hudson River as part of an artistic excursion. It has created and demonstrated a Baker fan—originally used to test the horsepower that a steam engine generated. Similarly, William Gould, a design consultant in San Diego is also trying to revive old steam engines. With help from original blueprints and SolidWorks computer-aided design software, he has detailed an 1879 Mason Bogie locomotive to discover exactly how it operated, something historians could not quite determine. Photoshop software allowed him to exactly match the train's color scheme based on a few paint chips from an original model.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(09):32-36. doi:10.1115/1.2009-SEP-2.
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This article discusses the significance of knowing exact constraint in successful design. Although not traditionally taught in mechanical engineering curricula, and not universally known among mechanical engineers, principles of exact constraint have been around for over a century. Designers of precision instruments have for decades used exact constraint, without which they simply would not achieve the precision required by many devices. Exact constraint has a well-developed theory applicable for design engineers. Applying it improves designs by avoiding over-constraint. Over-constrained designs lead to high stresses, tight tolerances, looseness, binding, and difficult assembly. Exact constraint is easier to picture in two dimensions than in three. In two dimensions, there are three degrees of freedom: two translations and one rotation. Some useful compromises to exact constraint are pinned and bolted connections, ball bearings, and tapered roller bearings. Another is in-situ adjustment of over-constraint as in, for example, the thread-adjusted foot pads of a clothes dryer or washing machine.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(09):38-43. doi:10.1115/1.2009-SEP-3.
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This paper presents views of award-winning inventor Saul Griffith on creating products that are environmental friendly. Griffith presents controlling carbon emissions as not so much a moral imperative, but as an active design choice. His start-up company, Makani Power, is working to tap the energy of strong, steady winds a half mile above the ground through use of high-tech kites. Another of Griffith’s projects, the web site Wattzon, was established to enable individuals to estimate their personal power consumption. According to Griffith, objects designed to endure over decades need to be not only functional, but also beautiful. Some of the conceptual framework that Griffith lays out as heirloom design is as much provocation as proposal. It is the increase in quality that Griffith said differentiates his concept of an heirloom-based economy from the idea that constraining carbon emissions is going to require undue sacrifice or even enforced poverty.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(09):44-48. doi:10.1115/1.2001-Sep-4.
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This article elaborates the constructal theory and its link with natural design. Constructal theory is the view that the generation of design (configuration, rhythm) in nature is a universal phenomenon, which is covered by a law of physics known as the constructal law. The constructal law is about direction in time. It provides a broad coverage of “designedness” everywhere, from engineering to geophysics and biology. The constructal law provides the student with strategy for how to pursue and discover design—the configurations or patterns—in both space and time. Constructal theory pushes design thinking closer to science and away from art. It tears down the walls between engineering and natural sciences. Because the configuration-generating phenomenon of “design” has scientific principles that are now becoming known, it is possible to learn where to expect opportunities for discovering new, more effective configurations. How to pursue these discoveries with less effort and time is the chief merit of the constructal law.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(09):54-56. doi:10.1115/1.2009-SEP-5.
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This article elaborates the social impact of the invention of Eli Whitney’s cotton gin. Before introduction of the gin, cotton had been a mildly interesting but barely productive crop. That changed dramatically with the advent of the gin. Prior to the gin's introduction, cotton fiber could only be separated from the sticky, embedded seeds by a manual operation. The procedure was so slow that cotton was just barely commercially attractive. So little could be produced that the greatest application was in such specialized little things as candle wicks. An individual would work 10 hours to separate a pound of fiber from seeds. Production increased by a staggering amount with the introduction of the cotton gin. A team of two or three could then process 50 pounds of cotton in a single day. Cotton growing suddenly became lucrative, and an unexpected tidal wave of cotton fields sprang up. It soon became by far the major export of the South.

Commentary by Dr. Valentin Fuster

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