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Mechanical Engineering. 2000;122(10):58-61. doi:10.1115/1.2000-OCT-1.
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This article focuses on that helicopters often display a rotor torque reading on their instrument panels to tell pilots how close they are flying to transmission design limits. With no measure of torque, a limit based on engine power is necessarily conservative. Torque monitors can increase a helicopter’s time between overhauls. Mechanical resonance, it seems, developed when the two engines were operated at matched torques. The torque meter lets the pilot split the torque to the two engines by 2 percent, diminishing any resonance. Permitted speculation, the Siemens researchers observed applications for their instrument beyond the traditional realm of torque measurement. In automotive applications, for instance, the researchers envision their torque measurement system one day being used in car engines to provide data in real time to the engine controls.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2000;122(10):62-69. doi:10.1115/1.2000-OCT-2.
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This article highlights that three approaches for the Apollo mission were considered and investigated early in the program: direct ascent, Earth orbit rendezvous, and lunar orbit rendezvous. Direct ascent would entail a direct shot from Earth to the moon, requiring an enormous rocket assembly, named the Nova rocket that required 15 first stage engines and would dwarf the Saturn V eventually selected as the launch vehicle. It also required a massive lunar landing vehicle to return the astronauts from the moon directly to Earth. At liftoff, the first stage burned 15 tons of fuel a second, requiring approximately 50,000 horsepower to power the fuel pumps to feed the engines. The Apollo 13 movie followed the actual flight with a fair degree of accuracy, recognizing that it had to compress four days of real-life tension into a two-hour motion picture. The film dramatized the explosion of the oxygen tank by showing the astronauts being thrown about in the cabin. In reality, the astronauts only heard a bang and then the warning alarm for low electrical bus voltage.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2000;122(10):71-74. doi:10.1115/1.2000-OCT-3.
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This article reviews that from the Cold War to Voyager, the work of Robert Goddard has received much recognition. Independently, Goddard started conceiving and designing a variety of air and space vehicles, and analyzing methods for propulsion and control. In 1903, Wilbur and Orville Wright had achieved powered flight with the three-axis control they had invented, but the flying machine was extremely difficult to manage. In 1907, while he was still an undergraduate, Goddard studied the dynamics of the Wright Flyer, and designed a gyroscope-based stabilizer for automatic control. His attempts to procure government funding were rejected by a United States military that did not recognize any value of rockets beyond the possibility of assistance at takeoff for aircraft. Rockets increasingly are supporting the marvels of our post-Cold War information revolution. The satellite-based Global Positioning System has brought the most sophisticated navigation system into the personal automobile. Within the century, Robert Goddard’s vision and life’s work begat far more than he could have imagined.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2000;122(10):76-80. doi:10.1115/1.2000-OCT-4.
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This article discusses that world-class manufacturers have been examining alternatives to the traditional energy market. Companies such as ABB in Zurich and Capstone Turbine Corp. in Chatsworth, CA, have been taking orders for installations of distributed generation plants running on natural gas. Capstone, which made its initial public offering this past summer, specializes in marketing microturbines for generating electricity. According to ABB, demand for alternative energy sources and distributed power generation—including wind farms, fuel cells, and small combined heat and power plants—is a rapidly growing market. This market has been sparked in large part by deregulation, which has forced power suppliers to put a higher priority on profitability. ABB has been working to build a reputation for concern over a number of sensitive issues, particularly protection of the environment and conservation of resources. ABB planned to build a power plant near the rural village of Broadclyst, which was also home to a number of articulate opponents who had a talent for organizing themselves.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2000;122(10):82-87. doi:10.1115/1.2000-OCT-5.
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This article focuses on the launch of Sputnik that transfixed the world by Carpenter Technology Corp. By incorporating advanced processing equipment, including a rolling mill, shape controller, annealing furnaces, wet grinders, and leveler with state-of-the-art automated control systems, Carpenter has improved the productivity and quality of its high value strip at a time when Space Shuttle launchings are taken in stride. The Carpenter specialty strip facility installed a cold rolling mill designed by Joseph Frohling GmbH of Olpe, Germany, in November last year, to increase rolling capacity and guarantee that the steel strip it produces meets the desired shape and thickness. In the Frohling mill, strip passes between two working rolls that reduce its thickness to sizes between 0.150 and 0.008 inch, at speeds up to 1500 feet per minute. Carpenter also installed three Ebner vertical annealing furnaces. Coiled strip on mandrels is unwound through each furnace, annealed, then rewound continuously to promote productivity.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2000;122(10):88-91. doi:10.1115/1.2000-OCT-6.
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This article highlights that up-front computer-aided engineering (CAE) dramatically decreases product lead time. Up-front CAE entails vesting responsibility for performing finite element analysis tests and other analysis tests with the design engineers. The designers use specific software packages to analyze their first-stage designs. This way, they can easily change designs that do not pass analysis tests-such as vibration or stress tests-before passing them on to an analyst for in-depth study. Not every engineering company, however, is turning to up-front CAE even as it faces the need to get products to market faster. Some engineers, like Zlatko Penzar, find that their present analysis hierarchy works just fine. He is a senior engineer for the fuel systems division of Mannesmann in Dusseldorf, Germany, another auto components supplier. Engineering departments have to find their own answer to the relationship between designer and analyst. The important thing is that once an answer is agreed upon, it happens the same way every day. A working atmosphere that functions reliably and smoothly is really the key to successful product design.

Commentary by Dr. Valentin Fuster

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