Editing Mechanical engineering (section)

==Areas of research==
Mechanical engineers are constantly pushing the boundaries of what is physically possible in order to produce safer, cheaper, and more efficient machines and mechanical systems. Some technologies at the cutting edge of mechanical engineering are listed below (see also [[exploratory engineering]]).

===Micro electro-mechanical systems (MEMS)===
{{See also|MEMS}}
Micron-scale mechanical components such as springs, gears, fluidic and heat transfer devices are fabricated from a variety of substrate materials such as silicon, glass and polymers like [[SU8]]. Examples of [[MEMS]] components are the accelerometers that are used as car airbag sensors, modern cell phones, gyroscopes for precise positioning and microfluidic devices used in biomedical applications.

===Friction stir welding (FSW)===
{{main|Friction stir welding}}

Friction stir welding, a new type of [[welding]], was discovered in 1991 by [[The Welding Institute]] (TWI). The innovative steady state (non-fusion) welding technique joins materials previously un-weldable, including several [[aluminum]] [[alloy]]s. It plays an important role in the future construction of airplanes, potentially replacing rivets. Current uses of this technology to date include welding the seams of the aluminum main Space Shuttle external tank, Orion Crew Vehicle, Boeing Delta II and Delta IV Expendable Launch Vehicles and the [[SpaceX]] Falcon 1 rocket, armor plating for amphibious assault ships, and welding the wings and fuselage panels of the new Eclipse 500 aircraft from Eclipse Aviation among an increasingly growing pool of uses.<ref>{{cite web|url=http://www.niar.wichita.edu/media/pdf/nationalpublication/Nov2-06.pdf|title=Advances in Friction Stir Welding for Aerospace Applications|access-date=12 August 2017}}</ref><ref>[http://sbir.nasa.gov/SBIR/abstracts/08/sbir/phase1/SBIR-08-1-A1.02-9322.html?solicitationId=SBIR_08_P1 Proposal Number: 08-1 A1.02-9322] {{Webarchive|url=https://web.archive.org/web/20160414231726/http://sbir.nasa.gov/SBIR/abstracts/08/sbir/phase1/SBIR-08-1-A1.02-9322.html?solicitationId=SBIR_08_P1 |date=14 April 2016 }} – NASA 2008 SBIR</ref><ref>{{cite web|url=http://www.ntefsw.com/military_applications.htm|title=Military Applications|access-date=15 December 2009|archive-url=https://web.archive.org/web/20190131095213/http://www.ntefsw.com/military_applications.htm|archive-date=31 January 2019|url-status=dead}}</ref>

===Composites===
[[File:Kohlenstofffasermatte.jpg|thumb|Composite cloth consisting of woven carbon fiber]]
{{main|Composite material}}

Composites or composite materials are a combination of materials which provide different physical characteristics than either material separately. Composite material research within mechanical engineering typically focuses on designing (and, subsequently, finding applications for) stronger or more rigid materials while attempting to reduce [[weight]], susceptibility to corrosion, and other undesirable factors. Carbon fiber reinforced composites, for instance, have been used in such diverse applications as spacecraft and fishing rods.

===Mechatronics===
[[Mechatronics]] is the synergistic combination of mechanical engineering, [[electronic engineering]], and software engineering. The discipline of mechatronics began as a way to combine mechanical principles with electrical engineering. Mechatronic concepts are used in the majority of electro-mechanical systems.<ref>{{Cite web|url=https://www.ecpi.edu/blog/what-is-mechatronics-technology|title=What is Mechatronics Technology?|website=ecpi.edu|date=19 October 2017|language=en|access-date=9 September 2018}}</ref> Typical electro-mechanical sensors used in mechatronics are strain gauges, thermocouples, and pressure transducers.

===Nanotechnology===
{{main|Nanotechnology}}

At the smallest scales, mechanical engineering becomes nanotechnology—one speculative goal of which is to create a [[molecular assembler]] to build molecules and materials via [[mechanosynthesis]]. For now that goal remains within [[exploratory engineering]]. Areas of current mechanical engineering research in nanotechnology include nanofilters,<ref>Nilsen, Kyle. (2011) [http://soar.wichita.edu/dspace/handle/10057/3997 "Development of Low Pressure Filter Testing Vessel and Analysis of Electrospun Nanofiber Membranes for Water Treatment"]</ref> [[nanofilms]],<ref>''Mechanical Characterization of Aluminium Nanofilms'', Microelectronic Engineering, Volume 88, Issue 5, May 2011, pp. 844–847.</ref> and nanostructures,<ref>{{Cite web|url=http://www.cise.columbia.edu/nsec/|title=Columbia Nano Initiative}}</ref> among others.
{{See also|Picotechnology}}

===Finite element analysis===
{{main|Finite element analysis}}

Finite Element Analysis is a computational tool used to estimate stress, strain, and deflection of solid bodies. It uses a mesh setup with user-defined sizes to measure physical quantities at a node. The more nodes there are, the higher the precision.<ref>{{Cite web|url=http://user.engineering.uiowa.edu/~bme083/lecture/lecture04_020303.pdf|title=Introduction to Finite Element Analysis (FEA)|last=Xia|first=Ting|date=3 February 2003|website=UIOWA Engineering|archive-url=https://web.archive.org/web/20170830001308/http://user.engineering.uiowa.edu/~bme083/Lecture/Lecture04_020303.pdf|archive-date=30 August 2017|url-status=dead|access-date=4 September 2018}}</ref> This field is not new, as the basis of Finite Element Analysis (FEA) or Finite Element Method (FEM) dates back to 1941. But the evolution of computers has made FEA/FEM a viable option for analysis of structural problems. Many commercial software applications such as [[NASTRAN]], [[ANSYS]], and [[ABAQUS]] are widely used in industry for research and the design of components. Some 3D modeling and CAD software packages have added FEA modules. In the recent times, cloud simulation platforms like [[SimScale]] are becoming more common.

Other techniques such as finite difference method (FDM) and finite-volume method (FVM) are employed to solve problems relating heat and mass transfer, fluid flows, fluid surface interaction, etc.

===Biomechanics===
{{main|Biomechanics}}

Biomechanics is the application of mechanical principles to biological systems, such as [[human]]s, [[animal]]s, [[plant]]s, [[Organ (anatomy)|organs]], and [[Cell (biology)|cells]].<ref>{{cite journal|doi=10.1016/j.cub.2005.08.016 |title=Mechanics of animal movement|year=2005 |last1=Alexander |first1=R. Mcneill |journal=Current Biology |volume=15 |issue=16 |pages=R616–R619 |pmid=16111929 |s2cid=14032136 |doi-access=free}}</ref> Biomechanics also aids in creating prosthetic limbs and artificial organs for humans.<ref>Phoengsongkhro, S., Tangpornprasert, P., Yotnuengnit, P. et al. Development of four-bar polycentric knee joint with stance-phase knee flexion. Sci Rep 13, 22809 (2023). https://doi.org/10.1038/s41598-023-49879-4</ref> Biomechanics is closely related to [[engineering]], because it often uses traditional engineering sciences to analyze biological systems. Some simple applications of [[Classical mechanics|Newtonian mechanics]] and/or [[materials science]]s can supply correct approximations to the mechanics of many biological systems.

In the past decade, reverse engineering of materials found in nature such as bone matter has gained funding in academia. The structure of bone matter is optimized for its purpose of bearing a large amount of compressive stress per unit weight.<ref>{{Cite journal|title=Tensile strength of bone along and across the grain|journal= Journal of Applied Physiology|volume= 16|issue= 2|pages= 355–360|last=Dempster|first=Coleman|date=15 August 1960|doi=10.1152/jappl.1961.16.2.355|pmid= 13721810}}</ref> The goal is to replace crude steel with bio-material for structural design.

Over the past decade the [[Finite element method]] (FEM) has also entered the Biomedical sector highlighting further engineering aspects of Biomechanics. FEM has since then established itself as an alternative to [[in vivo]] surgical assessment and gained the wide acceptance of academia. The main advantage of Computational Biomechanics lies in its ability to determine the endo-anatomical response of an anatomy, without being subject to ethical restrictions.<ref>Tsouknidas, A., Savvakis, S., Asaniotis, Y., Anagnostidis, K., Lontos, A., Michailidis, N. (2013) The effect of kyphoplasty parameters on the dynamic load transfer within the lumbar spine considering the response of a bio-realistic spine segment. Clinical Biomechanics 28 (9–10), pp. 949–955.</ref> This has led FE modelling to the point of becoming ubiquitous in several fields of Biomechanics while several projects have even adopted an open source philosophy (e.g. BioSpine).

===Computational fluid dynamics===
{{main|Computational fluid dynamics}}

Computational fluid dynamics, usually abbreviated as CFD, is a branch of fluid mechanics that uses numerical methods and algorithms to solve and analyze problems that involve fluid flows. Computers are used to perform the calculations required to simulate the interaction of liquids and gases with surfaces defined by boundary conditions.<ref>{{Cite web|url=https://www.simscale.com/docs/content/simwiki/cfd/whatiscfd.html|title=What is CFD {{!}} Computational Fluid Dynamics? — SimScale Documentation|website=www.simscale.com|language=en|access-date=9 September 2018}}</ref> With high-speed supercomputers, better solutions can be achieved. Ongoing research yields software that improves the accuracy and speed of complex simulation scenarios such as turbulent flows. Initial validation of such software is performed using a wind tunnel with the final validation coming in full-scale testing, e.g. flight tests.

===Acoustical engineering===
{{main|Acoustical engineering}}

Acoustical engineering is one of many other sub-disciplines of mechanical engineering and is the application of acoustics. Acoustical engineering is the study of [[Sound]] and [[Vibration]]. These engineers work effectively to reduce [[noise pollution]] in mechanical devices and in buildings by soundproofing or removing sources of unwanted noise. The study of acoustics can range from designing a more efficient hearing aid, microphone, headphone, or recording studio to enhancing the sound quality of an orchestra hall. Acoustical engineering also deals with the vibration of different mechanical systems.<ref>{{cite web |url=http://learn.org/articles/What_is_the_Job_Description_of_an_Acoustic_Engineer.html |title=What is the Job Description of an Acoustic Engineer? |work=learn.org}}</ref>