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Mechanical Engineering. 2018;140(09):S4-S10. doi:10.1115/1.2018-SEP6.
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Over the past six years, researchers at Villanova University (VU) and the Golden West Humanitarian Foundation (GWHF) have developed an integrated research and educational program focused on the use of mechatronics and robotics in humanitarian explosive ordnance disposal (EOD) and mine action. In the following article, I will talk about this program, discuss two ongoing projects - a low-cost EOD robot and an automated ordnance identification system - and talk about how we have successfully integrated students in the work. There are many opportunities for the DSCD community to get involved in this area and hopefully this article will pique your interest.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2018;140(09):S11-S16. doi:10.1115/1.2018-SEP8.
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There is growing public consensus that the system of mass incarceration in the United States needs reform. More than 2.2 million residents (0.73%) of the United States were held in state or federal prisons or in local jails at the end of year 2010 [1]. This incarceration rate is the highest in the world, and disproportionately affects racial and ethnic minorities: 4.35% of black males were held in custody compared to 0.68% of white males in 2010.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2018;140(09):S17-S23. doi:10.1115/1.2018-SEP7.
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Feedforward (FF) control uses a priori knowledge about a given system and its disturbances to influence the system’s behavior in a pre-defined way. However, unlike feedback (FB) control, it does not adjust the control signal (or manipulated variable) in response to how the system actually reacts. In other words, FF control is proactive while FB control is reactive. Model-inversion-based FF (MIBFF) control is a specific type of FF control where the control variable is determined by inverting a model of the system to be controlled. It is very popular for its use in output tracking control problems, where the goal is to force the system’s output to follow a desired trajectory. Output tracking is critical in several different applications, e.g., in manufacturing, robotics, automotive, aerospace, and is typically achieved using a combination of FF and FB control. As motivating examples, consider MIBFF in ultra-precise wafer scanners used in photolithography (see Sidebar S1) and in desktop 3D printing (see Sidebar S2). As these motivating examples illustrate, non-minimum phase (NMP) zeros often arise in practical engineering applications due to non-collocated sensors and actuators, fast sampling, etc. MIBFF for systems with NMP zeros is arguably the most important (and certainly the most researched) issue related to MIBFF.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2018;140(09):S52-S53. doi:10.1115/1.2018-SEP4.
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The mounting of a jet engine under the wing of an airliner can be a daunting task for turbofan engineers.

Thrust forces generated by gas path momentum flow changes in a jet engine are transmitted by pressure (and friction) forces on stators and struts attached to the engine case. Case engine mounts then transmit the thrust forces (as high as 100,000 pounds thrust on the largest engines) to the wing pylons to pull the plane forward. The mounts must also support the engine weight (as high as 20,000 pounds) and carry nacelle flight loads.

Engine bypass ratios are increasing (12:1 on the new geared fan engines), with fan sizes ever growing (178 inch diameter fan on the new GE9X). Mounting these new engines under a wing can present new challenges.

During the early days of its introduction in the late 1960’s, Boeing’s iconic 747 jumbo jet had engine mount problems. These are examined, together with their solution.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2018;140(09):S54-S55. doi:10.1115/1.2018-SEP5.
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This paper describes a selection of Baker Hughes, a GE company (BHGE) activities to support Gas Turbine (GT) design and operation from simple to more elaborate applications of Machine Learning (ML).

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2018;140(09):31-35. doi:10.1115/1.2018-SEP1.
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Like many great discoveries, the Antikythera Mechanism was found by accident. In time, however, analysis using X-ray and other advanced imaging revealed its true nature, and the Antikythera Mechanism is now considered as important for technology and sciences as the Acropolis for the architecture and arts. The object is the remains of the earliest known analog computer. Now we know that it was an extremely advanced mechanism that could be used to calculate and predict astronomical events. This article shows how researchers from the Aristotle University of Thessaloniki, Greece, used sophisticated imaging tools to gather data and create a working model to test their theories against the recreated mechanism itself.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2018;140(09):37-41. doi:10.1115/1.2018-SEP3.
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Farmers could save time and money if they could troubleshoot tractors themselves, but have no access to the built-in software diagnostic tools that are accessible only to authorized servicepeople. The problem is so widespread that Nebraska farmers have taken it up with their state legislators, hoping to gain the legal right to access these diagnostic tools. These farmers are the latest members of a grassroots movement that is lobbying for what they call the “right to repair.” The movement’s goal is to give consumers the legal right to acquire parts and fix machines or devices that they have purchased, Right-to-repair activists want to break that monopoly with a healthy repair ecosystem so consumers can get repairs and parts at reasonable cost. This article takes a closer look at the current status of the movement.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2018;140(09):43-47. doi:10.1115/1.2018-SEP2.
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In the United States, the highest incidence of ACL injury is to athletes, many of whom are soccer players. Surgery is often required to repair those torn ACLs, and surgeons are working with mechanical engineers to better understand the physiology of children’s knees in order to better repair the injuries–or perhaps avert them entirely. This article delves into how these engineers and biomechanics specialists are applying techniques normally reserved for hard materials like steel to soft tissue.

Commentary by Dr. Valentin Fuster

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