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Mechanical Engineering. 2016;138(09):S3-S7. doi:10.1115/1.2016-Sep-4.
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This article presents an overview of a control systems perspective. An electric field when applied to yield functional tasks is called as functional electrical stimulation (FES). FES is commonly prescribed as a treatment for various neurological disorders. Given the existence of regions in the crank cycle where it is inefficient to produce torque, a motor can be included as another torque source. FES control of the muscles yields cadence tracking in torque efficient regions, while the motor yields cadence tracking when it is efficient for the limbs to produce torque. The inclusion of a motor enables switching between stable systems and eliminates the need for the development of sufficient dwell-time conditions. Hence, the development of adaptive switched controllers for motorized FES-cycling systems may have a closer horizon. The inclusion of a motor also expands the possible control objectives that can be pursued.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2016;138(09):S8-S13. doi:10.1115/1.2016-Sep-5.
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This article demonstrates a multidisciplinary approach that proposes to augment future caregiving by prolonged independence of older adults. The human–robot system allows the elderly to cooperate with small flying robots through an appropriate interface. ASPIRE provides a platform where high-level controllers can be designed to provide a layer of abstraction between the high-level task requests, the perceptual needs of the users, and the physical demands of the robotic platforms. With a robust framework that has the capability to account for human perception and comfort level, one can provide perceived safety for older adults, and further, add expressively that facilitates communication and interaction continuously throughout the stimulation. The proposed framework relies on an iterative process of low-level controllers design through experimental data collected from psychological trials. Future work includes the exploration of multiple carebots to cooperatively assist in caregiving tasks based on human-centered design approach.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2016;138(09):34-39. doi:10.1115/1.2016-Sep-1.
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This article explores impact and advantages of information technology on manufacturing industry. Information technology on the factory floor promises a revolution in productivity. The industrial hype machine is among the favorites because of its full-on mashup of manufacturing with modern information technologies. There is use of intelligent software and machines to interact with one another (and with people) autonomously, both in the factory and through the cloud. According to the experts, this new combination of brains and muscle will revolutionize manufacturing in ways that rival the introduction of steam, electricity, and automation. It is foreseen that factory machines and logistics equipment would communicate with one another autonomously to assign and route jobs through the factory – and reroute them when unexpected problems arise. Cloud-based artificial intelligence would constantly compare parts and processes to optimize performance. As software gets better at communicating, ubiquitous sensors are adding more data to the mix.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2016;138(09):40-45. doi:10.1115/1.2016-Sep-2.
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This article discusses various aspects of data and manufacturing innovation. Industry today is rapidly adopting digital thread, a best practice in product data management that emphasizes a closed-loop process in which product lifecycle data is linked and traceable to design intent. The best practices in design and manufacturing stand in stark contrast to data revolutions being fomented in other fields. The data ecosystem is the collective memory of the complete output of a project, from conception to post-production and lifecycle activity for its artefact. It must encompass the dead ends as well as the amazing insights; the unbuilt alternatives and the simulation tests for prototypes; the information arcs traced out in the course of design and manufacturing process; and the consumer reviews and in-service information feeds from devices in the field. Vision of design requires engineers, designers, and manufacturers to reconsider some long-held beliefs about best practices. Computer scientists are developing solutions that might enable this transition; however, enterprises need to commit to underlying processes and cultures that will truly affect change.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2016;138(09):46-51. doi:10.1115/1.2016-Sep-3.
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This article emphasizes the importance of safety standards and codes developed by ASME for ensuring construction safety. Within the committee framework managed by ASME, the B30 standards committee is always looking to incorporate the industry's latest technological advances and best practices. While the basic principles of ancient machines are still applicable in many modern lifting devices, advances in materials and technology have allowed for cranes to be adapted to aid in accomplishing difficult and unusual tasks. Some cranes are even used to erect other cranes, which then go on to build the skyscrapers that dot our skyline. Even with all these changes, ensuring safety is just as important today as it was in 1916. ASME is leading the way in helping to ensure cranes can be a common and essential part of the everyday landscape.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2016;138(09):76-77. doi:10.1115/1.2016-Sep-6.
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This article throws light on details of jet engine thrust. The momentum flux of the engine exiting flow is greater than that which entered, brought about by the addition of the energy input from combusted fuel, and giving rise to engine thrust. Thrust arises from pressure and frictional forces on these surfaces, e.g., blades, vanes, endwalls, ducts, etc. This interior force view of thrust is easy to visualize but quite another thing to actually measure. In doing research on secondary flow in gas turbine passages, researchers have measured both steady-state momentum changes and surface forces, in the much simpler case of a turbine blade cascade. The thrust values for each component in the Rolls-Royce single spool engine have been shown in this paper. It has been noted that from the compressor, gas path flow enters the engine case diffuser, where a pressure gain produces another component of forward thrust of 2,186 lbt. Newton’s second law of motion allows us to examine engine component behavior that exhibits both forward and rearward propelling forces, which results in the net thrust our airline passengers have purchased.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2016;138(09):80-82. doi:10.1115/1.2016-Sep-7.
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This article presents a study on common design challenges of large and small turbofans. Turbofan engines powering large transport aircraft have demonstrated much different design objectives than business-jet turbofans including thrust, range, mission type, development cost, unit price, maintainability standards, and production quantities. Prolific use of ‘thermal barrier coating’ has helped turbine designers compensate for the inability to distribute a large quantity of small diameter film holes over the turbine blade surface. The historical trends in overall pressure ratio observed for both large and small turbofans have parallel slopes. Small turbofans lag behind the larger engines due to the miniaturization required for low flowrates characteristic of the smaller engines. These trends are qualitatively demonstrated, showing the growth in both the overall engine pressure ratio and turbine inlet temperature for several decades. It has been noted in this paper that the importance of high-performance impeller designs and intricate turbine blade cooling concepts for very low compressor exit corrected flows has not yet been fully appreciated.

Commentary by Dr. Valentin Fuster

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