Pan, Menghsuan
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Actuators Menghsuan (Sam) Pan Cluster 3 Table of Contents Actuator History of Actuator Motion & Energy of Actuator Types of Actuator MicroElectoMechanical System Internal Combustion Engine Jean J d'Al d'Alembert b t Background & Eduation Field Studied Contribution What is an actuator? A device convert energy into mechanical energy MSM actuator History… History … Industrial I d i lR Revolution l i – 18th century Invention of steam engine marked the beginning of actuator history. 1769 Watt: Fly Fly--ball generator 1832 William Sturgeon: Electric Motor History… History … (Cont.) (Cont ) 1868 J.C. Maxwell: theory to predict oscillatory behavior 1930s Charles Kearns :bonded resistance strain gauges 1960s – Resent MicroEletroMecchanical System Motion Created… Created… Linear motion motion in one direction Rotary motion circular i l motion ti Oscillatory motion opposite directions at regular intervals Power Source (Mechanical Actuator) Air Pneumatic cylinder y (Air cylinder) Electricity y Electric motor Liquid Hydraulic cylinder Pneumatic cylinder Using compressed air or gas as power source Convert potential energy in compressed air into mechanical energy. Gas pressure Atmospheric p p pressure Electric Motor Powered by electricity and magnets Rotary y Motion Magnets poles and rotation t ti Hydraulic cylinder Powered by pressurized liquid (Usually ( y oil)) Piston divides cylinder into two chambers Hydraulic pressure acts on the piston to create motion. Types of Actuators Single Single--acting actuator Energy is used in a direction A spring is used for the other Hydraulic Single-Acting Valve Actuator Types of Actuator Double Double--acting actuator Energy is used in both directions Hydraulic Double-Acting Valve Actuator MicroElectroMechanical (MEM) System Microfabrication technology Fabrication of miniature structures (micrometer size). Micromachining Fabricated in manner of integrated circuits Silicon substrates Slice of semiconductor material Microactuator A microscopic servomechanism Classes of microactuators Electrostatic Electromagnetic Piezoelectric Fluid Piezoelectric Actuator Transducers convert electrical energy into mechanical h i l energy Precision positioning mechanism High electrical capacity Piezoelectric Pi l ti b buzzer Inkjet head ultrasonic motor Micromirror Mirrors in microscopic world Fiber optics Light beams will reflect off micromirror into a fibre. If micromicro-mirror has been actuated, beam will be sent to a different fibre. Internal Combustion Engine Use Chemical Energy as power source When Chemical reaction ti occurs, pressure will increase and mechanical energy will be created. Rotary Engine A type of internal combustion engine Use the pressure increase as power source when fuels are burned burned. Triangular rotor Mazda RXRX-7 Jean Le Rond d'Alembert (1717 – 1783) Thus metaphysics and mathematics are, among all the sciences that belong to reason,, those in which imagination has the greatest role. I beg pardon of those delicate spirits who are detractors of mathematics for saying this .... The imagination in a mathematician who creates makes no less difference than in a poet who invents.... Of all the great men of antiquity, Archimedes may be the one who most deserves to be placed beside Homer. Background Born: 17 Nov 1717 in Paris, France St Jean Le Rond Church Died: 29 Oct 1783 i P in Paris, i F France Mme Rousseau Mother in d’Alember’s eye Education A private school Destouches family Jansenist Collège des Quatre Nations Daremberg d'Alembert Study Field Mathematics Mechanics Physics Philosophy Theology Law Medicine Contribution Fluid mechanics D'Alembert's p principle p D'Alembert's formula D'Alembert's D Alembert s paradox Encyclopédie D'Alembert's D Alembert s principle Alternative form of Newton’s Second Law F − ma = 0 Reduce the situation from dynamics to statics. statics Created a imaginary force opposite and equal to the force acting on the object Resulting a kinetic equilibrium D'Alembert's D Alembert s Solution The method of d'Alembert provides a solution to the oneonedimensional wave equation that models vibrations of a string. The general solution can be obtained by introducing new variables and , and applying the chain rule to obtain ( 4 ) D'Alembert's D Alembert s Solution (Cont ) (Cont.) respectively, so plugging in and expanding then gives This partial differential equation has general solution where and are arbitrary functions, with representing a right right-traveling wave and a left left--traveling wave. D'Alembert's D Alembert s Solution (Cont ) (Cont.) The initial value problem for a string located at position as a function of distance along the string vertical speed p can be found as follows. From the initial Taking the derivative with respect to t then gives and integrating gives and D'Alembert's D Alembert s Solution (Cont ) (Cont.) the solution to the wave equation with specified initial conditions as D'Alembert's D Alembert s paradox Drag is “ZERO” on a body moving with constant t t velocity l it relative to fluid. Three Assumption Flow is 1) incompressible 2) inviscid 3)) irrotational D'Alembert's D Alembert s paradox The pressure is symmetrical around th sphere. the h The paradox is due to the neglect of the effects of the effect of viscosity viscosity. (Cont.) (Cont ) References http://www.wisegeek.com/what-ishttp://www.wisegeek.com/whatis-an an--actuator.htm http://www.tkk.fi/Units/AES/projects/prlaser/actuators.htm p p j p http://www.directindustry.com/prod/edrive--design/electrichttp://www.directindustry.com/prod/edrive design/electric-ballball-screwscrew-linearlinear-actuatoractuator-1741417414354093.html http://china.rs-http://china.rs online.com/web/search/searchBrowseAction.html?method=getProduct&R=2224084#header http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=01325416 p p g p pj p http://www.gearseds.com/curriculum/learn/lesson_print.php?id=101 http://www.mathworks.com/access/helpdesk/help/toolbox/physmod/hydro/ref/ http://electronics.howstuffworks.com/motor.htm http://www.mems--exchange.org/MEMS/what http://www.mems exchange.org/MEMS/what--is.html http://mae.ucdavis.edu/dahorsley/ http://mae ucdavis edu/dahorsley/ http://auto.howstuffworks.com/engine1.htm http://auto.howstuffworks.com/rotary--engine.htm http://auto.howstuffworks.com/rotary http://www.electronics--manufacturers.com/products/sensorshttp://www.electronics manufacturers.com/products/sensors-transducerstransducersdetectors/piezoelectric--actuator/ detectors/piezoelectric http://webdocs.cs.ualberta.ca/~database/MEMS/sma_mems/mirror.html htt // bd lb t / d t b /MEMS/ / i ht l http://www--history.mcs.st http://www history.mcs.st--and.ac.uk/Mathematicians/D%27Alembert.html http://www.britannica.com/EBchecked/topic/150132/dAlemberts--principle http://www.britannica.com/EBchecked/topic/150132/dAlemberts http://mathworld.wolfram.com/dAlembertsSolution.html http://www.absoluteastronomy.com/topics/D%27Alembert%27s p y p _p paradox
