Questions tagged [mechanical-engineering]
Questions within the problem domain of mechanical engineering. Mechanical Engineering can be a broad field; consider choosing more specific tags if they apply.
1,012
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ANSYS APDL Shape memory effect option of SMA not working
I am trying to define the material properties of a shape memory alloy material in ANSYS APDL V15. There are material properties for Superelastic materials (SUPE option) and material properties for ...
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Forcing a part into "home position"
I have a design with two parts (at the moment):
a fixed 10cm ring with vertical tracks
a freely rotating block with a cut that may freely slide along that tracks:
I'm trying to find a low profile ...
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Deriving the amplitude of a coulomb (dry friction) damped spring
This is my first time posting anything, but I could not figure out the derivation of the amplitude of the spring for the 4 first oscillations. I am not acquainted with the effect and calculations of ...
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On a Diesel/hydraulic DMU train what exactly does the “go faster” lever control?
Let's say that you are driving a Diesel Multiple Unit† with either mechanical* (i.e. an actual gearbox with multiple ratios) or hydraulic (i.e. two or more torque converters) transmission. When you ...
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Questions regarding Cornering Stiffness for RC Car
I am a bachelor's level student tasked with modeling the vehicle dynamics of an RC Car that will be made to drive autonomously. I lack prior experience or particularly specific education with vehicle ...
user14808
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How to find press fit/ slip fit for non standard size parts?
I am looking for calculator or chart for slip fit and press fit for non standard size parts.
For example, I have oversized dowel pin 10mm +0.03/+0.01 diameter. I need to create a slip fit hole for ...
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What does a higher eject force do in a clutch?
I am looking at two clutches and the details on both are identical. The only difference is the eject force. One is 3300 and one is 3600. Does a higher eject force mean higher performance? And also ...
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Calculating the bending moment ($M$) of a beam as it relates to stress ($σ$) and strain ($ε$)?
I am trying to learn how to work out the bending moment for progressively complex systems to model a beam. I am assuming only one axis of motion (transverse = $y$).
For the basic equation of material ...
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How to analyze a bent beam: Stress concentration?
I am analyzing a beam, that has a bend in it. Intuitively and inspecting FEA results using a linear solver, there is a stress concentration at the bend of this I-beam.
The part was not a straight I-...
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Need some advice, control system animation. Appreciate some help!
I would like to have a 3d simulation of a helicopter landing on a ship.
I thought about using matlab for this, as a far as I know you can connect models from Simulink to virtual worlds using blocks, ...
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Schematic Reading - Fluid Control Limit Switch Question
Does limit switch LS1 remain pressed on until the piston moves to LS2?
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Why is there limited use of Y (Wye) fittings in a refrigeration system?
I'm a Mechanical Engineering intern currently working in HVAC and Refrigeration for grocery stores.
I'm looking into ways, with lower energy losses, to encourage equal flow distribution at liquid pipe ...
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Part to pierce the valve on a 16g CO2 cartridge and connect to a Solenoid valve
The specific part that I’m after is something that can connect to a solenoid valve and a CO2 cartridge that will break the seal on the end of the CO2 cartridge.
The solenoid valve connection is ...
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Worm Drive Clutching Mechanism
Problem Description
I have a project where I will need to be able to engage and disengage a worm drive (actually two of them). The worm drives are quite small. The worm gear is 49.2mm in diameter ...
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Quick return mechanism for spring-loaded screw
I am looking for a way to convert rotary motion to linear, but it should take less energy to get back to initial position than when going from initial position to the end position.
Specifically, a ...
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Mechanical vibration of objects
Do you happen to know relevant references in the literature that model the mechanical vibrations of a solid object (preferably antennas) by means of complex representations as a function of time?, i.e....
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Wall functions and separation in turbine blade simulation
I am simulating a turbine and I have some question about standard wall function in FLUENT.
Standard wall function requires $y^+$ value between 30 to 60 on the blade. but the following quote states:
...
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Explicit Dynamic ANSYS - Origami structure
I am working on a flat-foldable conical structure and I would like to carry out some dynamic tests on it (deployment to get the displacements and accelerations...).
I have designed the folded ...
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Effect on pavement by light tracked vehicles with rubber inserts
Is there data available to quantify the effect on pavement by light tracked vehicles with rubber inserts. One example of such a vehicle is the M113 armored personnel carriers shown below.
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How to reconfigure a control box unit for an SCN5 actuator
An image of the actuator is below. I have a setup that was given to me where there is two configurations, namely 50mm travel and back, and 75mm travel and back to home position. There are two switches ...
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Soft Material for life indication
I have a mechanism where two parts are screwed and unscrewed and I wish to incorporate a system by which the number of screwing and unscrewing can be indicated. I have thought of a method using the ...
Twin Spooler
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Water wheel Calculations required
Problem: I have been asked to help determine whether a waterwheel is able to generate enough power to run 5 x 15kW pumps in a remote location in Zambia where there is no constant power supply. I work ...
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How to calculate the coupler length in a crank rocker mechanism
I'm trying to learn a bit about building kinematic mechanisms by building a small project. The goal is to be able to open and close a box programmatically via a servo motor.
I have a small box that ...
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Simplifying head loss across a piping network
I am tasked with designing a compressed air piping network,with and would like to determine the pressure loss across the different layers of instruments
-now here is the 3D layout of the network. ...
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Designing a Safe and Crush-proof Pokemon playing card box using a 3D Super-Elipsoid
My friend has two young Pokemon-addicted sons who carry their 60-card playing decks with them everywhere, typically in a cargo pants pocket. Unfortunately, they have either managed to destroy every ...
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How Can You Calculate Force to Overcome Friction From an O-Ring Seal?
I essentially have a piston in a tube that is sealed with an O-Ring and actuated with a solenoid.
The friction of the O-Ring however, is higher than estimated (guessed as far as I can tell) by the ...
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What is "Torque Break"?
I am looking at the specifications for thread lockers, and henkel/loctite specify "Torque break" and "Torque prevail" in in./lb. as shown in the link below:
http://www.na.henkel-adhesives.com/...
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How do I loop through annotations in NX using the NXOpen API in VB?
I'm writing a script to extract all the dimensions from a 2D drawing in NX. In doing so, I have been able to get the dimensions and tolerances on all sheets, along with the zone numbers. This has been ...
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How can a planetary gearset "work" with gears whose pitch diameters are not tangent?
Somewhat new to the gear-world here, so I am trying to understand something. Most of the literature an examples of planetary gearsets that I've seen so far have described a relationship where the ...
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Model order reduction - Criag Bampton method
I am trying to understand how model reduction works, more specifically the Criag Bampton method. I would like to implement this method on a simple model in Python. I have been reading the following ...
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Pv Diagram of a pressure cooker
For a bit of self training in thermodynamics, I've been trying to think of some random systems and go ahead and try to solve them, some of these things I've stolen from random googling of university ...
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How can I map a global spherical position of a central normal vector to the rotation of 2 perpendicular motors?
I have a machine that rotates two concentric frames. The outer frame has a motor that rotates it relative to the global y-axis, and the inner frame has a motor that rotates it about the outer frame's ...
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Modeling rigid body dynamics: Trouble with equations, encountering nonsense answers
Hi, I am working on modeling a simple rigid body dynamic system through a certain range of motion. Here is the picture of the system.
I am trying to solve the system for the variables $x_1'', y_1'', ...
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The behavior of the stress-strain curve of metal, containing a void
Let's assume that in a metal sample without any dislocation, there is a void. Then we conduct a uniaxial tensile test.
user28031
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Why funnelling air in order to increase the velocity is a bad idea when generating power
Disclaimer: I’m not trying to violate the conservation of energy here; I know that’s impossible for us mortals. I think I’m either wrong or not considering something, I just want someone to point it ...
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How does NASA's QueSST X-59 jet work?
The QueSST (Quiet Supersonic Transport) is a project to create a more diffuse sonic boom in order to use supersonic flight commercially without the usual abrupt 1~2 psf pressure spike damaging the ...
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Glass bottle with a prolonged neck that continues into the inner space
Is it possible to create following two shapes from glass using currently known glass mass production techniques?
Shape #1: bottle with a prolonged neck that continues into the inner space, like this (...
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Is having a keyway in aluminium for 30Nm a bad idea?
I'm designing an aluminium shaft hub for a 16mm keyed shaft with a maximum torque of 30Nm. However, stress analysis tells me that the keyway can suffer too much stress:
If my understanding is correct,...
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How is motor torque related to capstan equation?
I know that capstan equation relates $T_{in}$ and $T_{out}$ as $T_{out} = T_{in}e^{u \cdot F_c}$, where $u$ is friction coefficient and $F_c$ is wrap (slip) angle. In my situation, the capstan is ...
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How to measure / calculate Tait-Bryan angles of a moving platform in SimMechanics
I exported a model of the mechanism created in SolidWorks to SimMechanics in order to explore the possibilities of control. To solve the problem, i need to know the angular position of the mobile ...
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What is the kinetic energy required to impact the surface of asphalt roads?
I am trying to find estimates of the minimum kinetic energy required to impact the surface of asphalt roads as a first-order impact assessment of road functionality to rockfall (i.e. boulders hitting ...
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Etymology of the term "journal bearing"
Typically the word "journal" refers to a collection of written records, experiences, or transactions. However, there is a common type of bearing known as a sleeve bearing, radial bearing, or journal ...
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Is a Geodesic Dome (fuller dome) that floats possible? What material or engineering effort would it take?
Buckminster Fuller has popularized Geodesic Domes (invented by Dr. Walther Bauersfeld who based it on the use of convex polyhedrons), and thus, making buildings with a very large roofs that don't ...
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Center of rotation (rigid body)
I know the meaning of (instantaneous) “center of rotation” and “center of zero acceleration” for a rigid body. I know that they do not coincide (in general) and that their positions change with the ...
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Efficiency of a planetary gearbox as a function of the lubricants viscosity
So I have a client that is asking about if they should switch from one lubricant to another in a planetary gearbox they have.
The main advantage that this new lubricant has is that it has a much ...
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Thread identification
I am having a very difficult time identifying this thread. This part is a plug that I am trying to replace because the threads were stripped.
The best fit for pitch is 11 threads per inch (imperial), ...
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How do you calculate the frictional losses in wire ropes over sheaves?
I am currently pulling a load with a wire rope that is moved through a system of sheaves, but had to replace a smaller wire rope cable (1/2") with a larger wire rope cable (3/4"). The sheave/wire ...
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About Shot blast machine
In addition to the machine parts we manufacture in our foundry we also produce high quality steel abrasive including low carbon round corn, cut wire, steel grit amongst others. We will be happy to ...
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Forces on a wheel during braking (Quarter Vehicle Model)
I have created a simple xcos simulation for quarter wheel using the equations given at the bottom of the image.
I understand the total torque on the wheel will be the braking torque and the friction ...
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Iris mechanism nomenclature - need help to enable better search results
I'm researching iris mechanisms with the goal of building a functioning, weather-sealed door. I am learning much as I go along, but am faced with a challenge in nomenclature (I am not an engineer).
I ...
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