# Engineering Stack Exchange Community Digest

## Top new questions this week:

### Why are many compliant mechanisms only flexible in the joints?

I've been playing around with 3D printing some compliant mechanisms, mostly to get precise linear motion, and I've noticed that many commercial compliant mechanisms are often designed like this: ...

design 3d-printing flexures

### Non-standard Door Hinge Spacing

The usual woodworker/house builder rule of thumb is to place the top hinge 6" (150 mm) from the top of the door, and the bottom one 9" (228 mm) from the bottom - the common reason for this ...

door hinge

### Improving ball feeder design

I designed this ball feeder for my robot however I'm experiencing frequent ball jams as the ball is stuck against the wall of the hole entry or just a ball being moved left and right not entering the. ...

mechanical-engineering motors design servo

### Modeling Vehicle Acceleration - Simulink

Hello I am modeling a vehicle that has a seperately excited DC motor as the power plant utilizing the constant-torque and constant-power regions for traction. The acceleration is governed by the ...

### What is a 'rocker slab'?

See below for an extract from a general arrangement drawing from the 1980s. It makes reference to a '9" rocker slab' which appears to be a slab supported by steel beams. Does anyone have any ...

civil-engineering reinforced-concrete

The solutions are F(DE)=134.38N, a(D)=2.016m/s^2 , α=1.29rad/s^2, a(C)=7.828m/s^2 I agree that the FBD and the KD are these: Then to solve this problem I've done: $$\sum M_{c}= I \alpha_{BCD}$$ $<=... applied-mechanics  asked by sputnik 3 votes  answered by NMech 1 vote ### Can you help me to interpret technical drawings? I'm trying to find out the angle/ length of the oblique line, or the solid angle of the conic part. This is what I've tried so far: According to the pythagorus theorem the length of the line is equal ... mechanical-engineering pumps technical-drawing  asked by Sam B 2 votes  answered by NMech 6 votes ## Greatest hits from previous weeks: ### What does "$\pm$0.5% F.S." mean? I've seen it in several data sheets - it is a measure of error of some kind, of course. The problem is I dont know the exact meaning. I've seen it in the context of repeatability, accuracy and ... nomenclature  asked by John H. K. 10 votes  answered by Russell McMahon 15 votes ### LO/LC, CSO/CSC Valve Definition Does any one here know of an authoritative source (ASME, ISA, NFPA, OSHA, etc..) that gives a definition for the following in one of their standards or codes and the number for that standard or code: ... mechanical-engineering valves standards  asked by Jrican 4 votes  answered by morristtu 2 votes ### How to define Knurl on drawing? I made this kind of knurl on shaft : but I am not sure how to be define on the drawing. I found some examples but not sure if they are correct. On the examples there type (GV) and depth of knurl and ... mechanical-engineering modeling machining  asked by Stenly 5 votes  answered by Tawhiri Matea 3 votes ### Gate width calculation for Passenger car design vehicle I am trying to figure out the minimum gate width required for parking a car inside the house which has a 15 feet road in front of it. Please refer to the image below: Plot is 20 feet wide. I have ... civil-engineering transportation  asked by Whiskeyjack 5 votes  answered by Akter U Azim 2 votes ### What is the meaning of vorticity and circulation? In fluid kinematics I can't understand the meaning of these terms : vorticity and circulation. Can somebody give me a description of these terms so that a lay person can understand them easily? fluid-mechanics  asked by M.Tarun 11 votes  answered by Algo 10 votes ### How to determine the characteristic length in reynolds number calculations in general? I understand that the reynolds number is given by the expression$Re=\frac{\rho v L}{\mu}$, where$\rho$is the density,$v$is the fluid velocity and$\mu\$ is the dynamic viscosity. For any given ...

fluid-mechanics

### What material is used to hold molten iron in a furnace?

When iron is melted, I guess it has to be transported and contained. I think the container in which it is has to be able to withstand higher temperatures than what you want to melt. According to this ...

metallurgy

## Can you answer these questions?

### Can someone please explain what a PT1 filter is in simple terms?

The context here is for determining how driveability filters are calibrated since most of them use pt1 filters to filter the torque demand.

control-engineering automotive-engineering

### Bulk edit or script multiple DXF files

I have several hundred .dxf files that are all pretty simple rectangles with MText inside. I am looking for a way to, in bulk, convert the MText to Polylines (TXTEXP) without having to open each file ...