Chuck
  • Member for 6 years, 8 months
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  • Virginia
Voltage controlled switch?
1 votes

I believe you are describing a charge pump. You don't give any specifics on what you're trying to do, though, so I can't really give meaningful feedback on anything else. Generally speaking, though: ...

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How to calculate the max torque due to angular momentum of a beam given motor specs
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1 votes

is it possible that the torque generated from the momentum of the beam I'm going to stop you right there. Momentum doesn't generate torque. Momentum is moment of inertia times speed. Torque is moment ...

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simulation of an attitude optimal Backstepping controller based quaternion for a UAV in MATLAB
1 votes

That is quite the wall of text. You don't need to rewrite an entire academic paper to ask a question (please don't). You failed to show what it is you thought you were supposed to get or what you ...

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Git, Mercurial, others -- what's the best system for an engineering team new to version control?
1 votes

Source control isn't going to fix your problems. Let's review: We don't have a way to allow multiple people to work on different components of a model simultaneously. Why do you have multiple people ...

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Designing a Parallel Robot by Autocad
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1 votes

I can only answer the question you asked about. You asked about a spherical joint, so I'll give advice about the spherical joint. First, are you using Autocad? That looks like Inventor. They are two ...

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How to model a sheet metal nut in SolidWorks?
1 votes

I can't tell what you want. A combination of a part and forming tool What? I want to drag this part into a closed sheet metal area and the holes for the nut should be created automagically ...

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stability/controllability of a finite time linear quadratic regulator
1 votes

How do you have an LQR with open loop control? I know that there would be these requirements if I were to implement a closed loop control A linear quadratic regulator is basically a multi input ...

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Selecting the correct strain gauge and metal thickness for custom load cell
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Mechanical designer here - how do you get an inside cut on a sharp angle like that? What tool makes perfect corners? You said, "On top of this plate I will mount four... bars of wood." So, if the ...

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Amperage draw for Servo
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1 votes

The datasheet for the device should always list a maximum or "stall" current. For this device, it's 2.5A. You can use that for a worst-case estimate of battery life by multiplying it by the amount ...

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Material for suspension that stiffens in higher speeds?
1 votes

Dampers. Resistive forces are inertias (m), dampers (b), and springs (k), and the equation is generally written: $$ F_{\mbox{applied}} = m\ddot{x} + b\dot{x} + kx \\ $$ That derivative term - $\...

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What's the term used for machine parts orientation naming on the sagittal plane and from inside the machine?
1 votes

There are globally accepted names for these positions, and they're even color-coded! If this is a really big issue, consider using port and starboard. This is used in nautical and aviation industries ...

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Calculating correct motor torque for windmill
1 votes

Torque, $\tau$, is required for rotational acceleration, $\tau = I\alpha$, and for viscous losses, $\tau = b\omega$. Here I'm using $\phi$ for angular position, $\omega$ for angular velocity, and $\...

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Is there a CE mark requirement for positive control logic?
1 votes

I don't know for sure, but I doubt that would be the case because all of the E-Stop circuits I have worked with signal shutdown on the transition from high to low; this ensures shutdown even if the E-...

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Sound insulation, absorption and diffusion. Can they be part of the same process when wanting to both soundproof and acoustically treat a room?
1 votes

Acoustic impedance is very similar (mathematically the same as) to electrical impedance. When an electrical wave hits something with infinite impedance (like unconnected wires), electricity doesn't "...

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How do you apply fits and tolerances when designing hole and shaft?
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1 votes

I think you may be getting a little confused here. There is a fit tolerance, which determines how easy it is to insert and rotate a pin in a joint, and then there is machining tolerance, which is how ...

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Motor selection
1 votes

I feel like I say this a lot, but it seems to be a commonly overlooked design spec. Torque is a force applied (orthogonally) at some distance, but torque is also moment of inertia times angular ...

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Calculate the force when given the moment
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1 votes

$$ \tau = 500 \mbox{Nm} \\ $$ $$ \tau = r \times F \\ \tau = |r| |F| \sin{(\theta)} \\ $$ If the lower left angle is $43^{\circ}$, then the top angle from the bar $r$ to vertical is then $180 - 90 - ...

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Is this pressure vessel feasible?
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1 votes

Sure. CO2 cartridges are made of steel and hold 850 psi. You want to use brass, which has 80% of the yield strength of steel (200MPa vs 250MPa) to hold 35% of that pressure. Not to mention the fact ...

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Exact procedure to mount a blanking spade near a butterfly valve
1 votes

You are correct, you can't disassemble a valve that's currently isolating system pressure. This means that you have to isolate the system (at least) one valve upstream of the valve you intend to blank....

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Is there a more active passive technique for removing humidity from the air besides salt blocks?
1 votes

I don't think you're going to find an answer that meets the intention of your question as I read it. It takes energy to convert water from a vapor to a liquid. Some materials (minerals, sugar, etc.) ...

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Bend allowances when making a C-shape plate
1 votes

In Inventor, you can select the location ("datum") you want to use for referencing where you intend the bend to be located. First, make a sheet metal part: Then, make the base face whatever you want ...

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Practical uses of superfluids
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Your comment, "my interest is more whether we can make machines waste less energy due to a lower friction and how such things can get realized" provoked me to respond: On an initial thought, a fluid ...

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How are blanking spades entered into gas pipelines?
1 votes

You are correct, blanks are installed at a pipe flange where two runs connect. Typically you break the joint and pry the flange apart to install the blank, but this can cause problems if/when the ...

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Controllability of $x' = Ax + Bu(t)$ implies controllability of $\left \{ \begin{matrix} x' = Ax + By \\ y'=u(t) \end{matrix} \right.$
1 votes

Couldn't you just define $y(t)$ and be done? $$ y'(t)=u(t) \\ y(t) = \int{u(t)}dt \\ $$ As long as the system is controllable, as defined by the controllability matrix $M$ being full rank, it doesn'...

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Looking for a formula that states the stiffness of a composite
1 votes

I don't think there is a formula. For metals, at least, these values are all derived empirically via extensive testing, such as the Charpy V-notch test, tensile testing, fatigue testing, etc. ...

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Height Increase by a Floating Cylinder Over a Larger Cylinder
1 votes

20cm diameter gives a cross sectional area of $\pi r^2$ or 314.15 cm2. 8cm diameter uses the same formula for a cross sectional area of 50.26 cm2. The free space around the float in which the water ...

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How to compute the size of a polygon moving along non-circular guide rails
0 votes

There's no uniform radius of curvature with your shape (c) so you can't have a closed series of rigid linkages that's capable of moving around the track. You can use a flexible link or cart as a ...

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Deriving the equations of motion for free-floating spacecraft with a single link robot arm
0 votes

Sorry I missed this over at Robotics. Your question is really unclear and you don't have a good diagram that helps it out at all. You say there is no gravitational field, there are no springs, there ...

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Dynamics of a rigid body in a system of two linear drives
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I am having a really hard time following your setup. First, you have the x-axis as the vertical axis, and the y-axis as the horizontal axis. Is this correct? And then there's a... surface?... when x = ...

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Damage differences in frontal collision of two vehicles and their speed
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Can the difference in damage be attributed to much different speeds of the two vehicles? Which speed? If the cars hit each other, then there is only one speed that matters - the speed of car A ...

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