Pete W
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Get average shape from 10k + files
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hmm. here's a shot in the dark. might require relatively simple surface. this is crude, the are much more sophisticated ways. research metric or distance for 3D shapes. (1) In a 3D modeling tool, ...

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Question on fluid flow measurement uncertainty
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In series would usually be best, with two caveats: the setup has to be such that the upstream meter does not affect the downstream meter, either systematically or by adding noise. if the total flow ...

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How to determine the force to empty a syringe containing high-viscosity fluid?
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Hard to say. Although the pressure is very high (up to 5kN/0.001m^2 = 5MPa), the velocity is super slow and Reynolds number is very low, deep laminar region. I wouldn't worry too much about roughness. ...

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Linear motion with triangle profile
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Probably many possibilities. Here's what comes to my mind: If the load is light, you could mount it on a timing belt. It could still be on a linear guide, to keep its motion perfectly straight. One ...

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3D linkage design - terminology
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I believe the general class of problem you may be looking is "inverse kinematics"

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How can I achieve good diffusion from an LED light source?
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Looking at microscope and laboratory optics, I think a ground glass optical diffuser was be used, instead of frosted glass. Typically small size however, and expensive. I believe the idea is that ...

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Vibration damping a bed from mechanical vibrations
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First of all, before looking at any solution, you need to characterize two things the frequency of the vibrational input, which you can measure by placing an accelerometer on the floor. There is a ...

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Applying ISO fits to radial bearings
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I think the answer to your question is yes, except it would not be an H7 but an H5 or H6. Here's the relevant page on roymech.org, which has brief explanation and tables. These fits are a ...

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What is the max speed and duty cycle of an air conditioner's magnetic clutch?
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TL;DR - you may be better off taking the torque from the shaft of a motor/generator (with appropriate reduction via gear or belt) It might be a tricky to get proportional action out of it, if it is ...

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Different results when applying equation
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doing it the hard way: Let A and B be distance from the corner A = r*cosϑ B = r*sinϑ dA/dt = (-r*sinϑ)(dϑ/dt) dB/dt = (r*cosϑ)(dϑ/dt) (dB/dt) / (dA/dt) = -cotϑ thus dB/...

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Liquid Level Control System Resistance
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If flow is q, and pressure is p, The linear flow characteristic "R" is defined such that p = (q)(R) This is directly analogous to V = IR in ohms's law, in the electrical analogy. If we ...

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Given 3 force measurements, what are estimated forces at other locations?
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I think the purpose of this question is the look at the balance of forces and moments, which must be the same for the 3-force group and the 4-force group. If the 4-force group is supposed to be ...

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PID controller - Counterproductive derivative
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The "D" in PID is often used when PI response produces overshoot in step response. Sometimes, definitely not always, there is misunderstanding of the problem. I don't really know how to ...

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Two 3/4HP / 500W motors to run in opposite directions, at precisely the same RPM, controllable from zero to 5000 RPM?
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As a mechanical alternative to gears, perhaps a double sided timing belt could be used to reverse direction and have essentially perfect sync.

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Looking for feedback on a lift bed power lift mechanism
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The general idea is worth working out. Looks like the max loading, and worst case for leverage is when the device is almost closed -- so draw it up also in that configuration, and do the analysis when ...

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Looking for feedback on a lift bed power lift mechanism
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If this doesn't work out, check out the "6 bar dump truck mechanism" on page 12 of this link

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Can you use the Hagen-Poiseuille equation for a pipe which radius is in the sub-millimeter region?
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Same answer as above, "Yes BUT..." This is from a practical point of view: Other than HPLC, nearly all "microfluidics" applications are far into the laminar region. Poiseuille's ...

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Pushing fluid through microfluidics
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A cheap way to realize low pressure differences (and a method that is nearly unbeatable for smoothness) is gravity. Fill everything with liquid, run input and outlet tubes to two beakers/buckets/etc, ...

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