Search results

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    Material that is bendable in certain conditions

    Try Googling both electroactive polymers and reverse piezoelectric materials.
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    Polyurethane Bonding

    Tried anything in the 3M Foamfast range?
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    Looking for Equation that can describe both scenarios

    You may find the following article of interest. If you don't have a subscription that covers it, please let me know. Ultimately it attempts to relate the governing equations for the behaviour of shocks when meeting a shear layer (such as at wing tips) to the travel of shock waves in traffic...
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    More Control on Racing Cars

    It doesn't necessarily need to be actively controlled (look at the Honda Prelude), and can help with stability (and probably tire wear) but usually incurs a weight penalty and added complexity.
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    Simple mechanisms to measure joules output?

    You could use a mechanical indicator to construct a PV diagram, then use a planimeter to measure the enclosed area. Commonly done with steam engines.
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    I Need Help Reading Table [Broken] should help. Also, the tapping drill size is the size drill used to produce a hole which can be tapped for a female connection.
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    Resonances of Cylindrical Shells with uniform radial pressure

    Try: Soedel, W., Vibrations of Shells and Plates, CRC Press (2004) Timoshenko, S., Theory of Plates and Shells, McGraw Hill (1959) Both of those have solutions for thin walled cylinders if memory serves correctly.
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    Where To Buy This Standard?

    That looks like the old German version of the Whitworth pipe thread standard. It's been superseded by: BS EN 10226-1:2004 BS EN 10226-2:2005 BS EN 10226-3:2005 There's an ISO standard as well - ISO 7-1. As for purchasing it, you can buy it from BSI amongst others. If you're a member...
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    Acoustics of metal alloys question

    You could do it Excel if you really wanted to! Matlab is perfect (Octave for open source if you're that way inclined), and I've carried out similar analyses in MathCAD, LabVIEW and even in C++. This is actually a typical exercise (for the beams anyway) for mechanical engineering students in a...
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    How is austenitic stainless steel made?

    A variety of alloying components inhibit the transformation from austenite to other phases. A typical 300 series stainless will have high chromium content and usually ~10% nickel, which prevents the transformation. Other additives are often used to reduce nickel content, keeping costs down.
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    Acoustics of metal alloys question

    With accurate material properties you can come up with simple analytical models that can predict some of these for you. For simple beam testing it's pretty simple to treat a single degree of freedom beam as follows. You could derive the equations yourself from the fourth order differential...
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    Applications for Mechanical Engineering - Reasoning

    It's cheating somewhat I'm sure, but I work as a researcher in the mechanics of materials in a mechanical engineering department of a university. I use the skills I learnt every day :) Before this I spent a while working for a design and engineering consultancy, where I was responsible for...
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    Method to Locate Footstep

    Gait analysis is often carried out using pressure sensing panels or footplates. One system I've used before is made by Tekscan. Alternatively, a very basic system of digital image correlation using two cameras could be carried out as suggested above. Have a marker on both shoes/feet, make...
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    Ever get the feeling that your door is unlocked?

    Bear in mind the different motions you could potentially need measure. If it's a deadbolt moving in translation, will an accelerometer tell you anything about its position when not in motion? If it's a handle or lock barrel rotating into position, actuating the bolt, can you use a bi-axial (or...
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    Coefficient of Friction

    Low coefficient of friction, conditioner, lubrication at the sample/platen interface in compression testing, relief and rake faces on cutting tools, bearings...plenty of things!
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    Rating the strength of steel?

    As minger says, the ultimate tensile stress is the maximum stress reached in a test. For a ductile material that necks considerably, the UTS will be higher than the stress at failure or rupture as the cross sectional area begins to decrease. Note that this is only the case for engineering...
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    Any papers/ articles on carbon fibre?

    ScienceDirect shows a plethora of journal articles looking at acoustic techniques in the field of CFRP.
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    Book on Strenght of materials

    I have a copy of Materials Science by Anderson et al (Chapman and Hall, 4th Ed) which is a handy reference - ISBN 978-0412341502.
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    Polymers with piezoelectric effect

    A typical piezoelectric film is polyvinylidene fluoride, PVDF. The piezoelectric effect means a charge is generated when a stress is applied, or a mechanical effect can be achieved by passing a charge across the sample. Goodfellow sell a variety of PVDF sheet which you can play around with.
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    Mechanical & Electrical Engineering degrees (UK)

    A 5 year masters? Is that with a sandwich year? Most of the UK courses I've seen are four years. Personally, a good mechanical engineering or electrical engineering degree from a good university would be better for employment prospects than a sole mechatronics degree. Typically in a UK MEng...
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    Elastic materials for suspension components

    If Hytrel suits your purpose except for its modulus, why not try exploring either another blend of Hytrel (there are quite a few) or an alternative TPE. Hybrar, from Kuraray, comes in a wide range of moduli too. To be honest I've only worked with the H7125 blend, but its modulus is certainly...
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    MS Student Calculator

    You forgot the part where you spend hours writing amusing words into memory because you found the alpha key and the corresponding buttons that are letters. No more are you constrained to just '71077345' or '55378008'! But seriously - when will you use it? For your studies, are you allowed to...
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    Bullet Penetration

    Nope. The closest you'll get is the procedure for finding the ballistic limit for bulletproof vests I mentioned above. There's a big difference between elephants too, so you'd have to find an standardised elephant surrogate for want of a better way of putting it - a thick block of gelatine...
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    Bullet Penetration

    1. Ft-lbf is a perfectly acceptable unit of energy in the ballistics world. Bear in mind that's pounds force times feet. 2. Let's extrapolate what you need from ballistic standards testing. For standardised vest tests, you find the ballistic limit by finding the bullet velocity at which 50%...
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    Piezoelectricity measurement

    Get an insulating film such as Mylar or Tyvek, about the same thickness as your piezo film. Cut a hole in it about the same size as your polymer film. Sputter / solder at one end of two equal strips of conductive adhesive copper tape for your outwards connections. Lay them down on either side...
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    Popping bubbles underwater

    Compare what you're describing to the phenomenon known as cavitation. You may not be able to initiate it by poking your slow moving bubble under water, but in a low pressure region caused by flow around a propeller screw you will often get bubble formation and collapse. This can generate...
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    Theoretical Armor Question - Joules Conversion

    Bringing this back into the real world a little bit, body armour is broadly speaking designed to do two things. One, stop the bullet from physically penetrating the armour layer and hence not enter your flesh. Two, reduce the peak depth of deformation behind the armour. For the first, the armour...
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    Relationship of Critical Damping Ratio in Elastomers

    Find it experimentally. Bear in mind that its loss tangent will be frequency dependent and can be measured in shear rheology, dynamic mechanical analysis or other method, or just drop a ball of the material from a variety of heights and measure the rebound heights for each successive rebound...
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    Good idea to do a language module in my MEng degree?

    I studied German at high school from 13 to 18, with high GCSE and A level qualifications. As a result, I chose that as my elective courses in the third and fourth year instead of project management, entrepreneurship or innovation management etc. As a result I found that my technical and...
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    Piezoelectric strips?

    I used metallised 25 µm biaxial sheet. I don't know about bonding with glass, never tried. I used Mylar PET sheet of the same thickness as an insulating and protective substrate. That way I ended up with a very thin, flexible load cell.