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Mechanical Engineering. 2012;134(08):30-35. doi:10.1115/1.2012-AUG-1.
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This article elaborates how anthropology is opening new design opportunities in everything from consumer products and computer interfaces to mechatronics systems and industrial design. Anthropology can reframe human understanding of familiar places and behavior. Unlike market researchers and designers, anthropologists start with people rather than products. Design anthropology has become a fixture in the tech world. Citrix, Claro, Facebook, Fujitsu, Google, IBM, Microsoft, Motorola, Nokia, and Sapient, all employ anthropologists. Even anthropologists employed by non-tech firms, such as JCPenney and Target, often work on the tech side. Design anthropology is the kind of lens that enables designers to see things in a new light. They can see the people who use a product and how they use it. They can also understand what the product means to the person who buys it.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2012;134(08):36-39. doi:10.1115/1.2012-AUG-2.
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This article outlines the challenges for automobile engineers in designing electric-drive vehicles. Understanding the way noise travels differently through an electric-drive vehicle is one of the main challenges for engineers as they design this new generation of vehicles. Moreover, bodies and chassis are evolving away from traditional sheet metal to more exotic materials, and consequently, the whole production process is being re-engineered. The power density of even the best battery is small when compared to the chemical energy in an identical volume of gasoline. Hence, electric vehicles (EVs) can at most eke out only around 100 miles per charge. Overcoming that challenge is the subject of decades-long research projects. The lithium-ion batteries found in most EVs generate so much heat in use that they require their own cooling systems. Temperatures of all cells within the battery pack also must be held within a few degrees of each other, lest internal current loops form that may slash battery life. Some other issues include cost, service life, and safety.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2012;134(08):40-43. doi:10.1115/1.2012-AUG-3.
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This article discusses recent changes in the design of pogo stick. Entrepreneur Brian Spencer and his father, Bruce, have designed a new pogo, which they call a Vurtego. The father and the son began sketching out a bold new direction in pogoing in the late 1990s. On the suggestion of Bruce Spencer, they designed a tube using air compression rather than a spring. In the garage, Bruce Spencer cobbled together a first prototype from PVC tubing and other plastic parts, and this new pogo stick worked well. The air spring lifted Spencer well off the ground. Through a series of refinements and trials, Spencer discovered that the key factor was the compression ratio. In addition to patenting the design of their stick, the Spencers have now also patented a range of maximum compression ratios, between 2.5 to 1 and 4.5 to 1.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2012;134(08):50. doi:10.1115/1.2012-AUG-4.
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This article describes the functioning of the gas turbine cogeneration power plant at the University of Connecticut (UConn) in Storrs. This 25-MW power plant serves the 18,000 students’ campus. It has been in operation since 2006 and is expected to save the University $180M in energy costs over its 40-year design life. The heart of the UConn cogeneration plant consists of three 7-MW Solar Taurus gas turbines burning natural gas, with fuel oil as a backup. These drive water-cooled generators to produce up to 20–24 MW of electrical power distributed throughout the campus. Gas turbine exhaust heat is used to generate up to 200,000 pounds per hour of steam in heat recovery steam generators (HRSGs). The HRSGs provide high-pressure steam to power a 4.6-MW steam turbine generator set for more electrical power and low-pressure steam for campus heating. The waste heat from the steam turbine contained in low-pressure turbine exhaust steam is combined with the HRSG low-pressure steam output for campus heating.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2012;134(08):52-53. doi:10.1115/1.2012-AUG-5.
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This article discusses the rewards and challenges for engineers in the wind energy sector. There are many advantages that wind brings to the energy mix. Wind turbines do not produce combustion byproducts and can generate electricity for comparatively low costs, in many cases comparable to some of the lowest-cost traditional methods such as natural gas fired combined cycle power plants. However, designing and maintaining a wind turbine is a challenging task, requiring close interaction between engineers of many different disciplines. The fundamental challenge in designing a wind turbine is for it to operate reliably and safely for twenty years or more, produce as much power as possible, and with the lowest possible initial and lifecycle costs. Meeting various requirements requires the participation of aerodynamicists, structural analysts, materials engineers, process engineers, and controls engineers, each of whose design decisions affect those of other members of the rotor, turbine, and wind power plant design teams.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2012;134(08):55. doi:10.1115/1.2012-AUG-6.
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This article discusses the performance optimization of wind turbine rotors with active flow control. An extensive multi-parameter investigation with a thorough matrix-grading system was performed to identify the most suitable solution for industrial quality, short/mid-term implementation on actual utility scale wind turbines. A very wide selection of aerodynamic flow control solutions was analyzed based on extensive multi-disciplinary literature review and through aerodynamic and aeroelastic simulations. It is suggested that the trailing edge devices have the most favorable performance in the field of system integration and mechanical design performance. Compliant structures like the flexible flap keep the number of moving parts to a minimum while maintaining high performance and manufacturing simplicity. The use of flexible and elastic materials based on polymers or rubber material improves the lightning strike resistance of these solutions and allows for low-cost large-scale production. The actuator principle, sensitivity, and reliability are decisive parameters, and pneumatic actuators seem to strike a good balance between performance, cost, and reliability.

Commentary by Dr. Valentin Fuster

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