(Part 2) Top products from r/AskEngineers

Other comments here are spot on.

The simplistic version that underlies all of them is humans are smart so they can identify a problem and approach the desired solution iteratively. This creates a feedback loop.

Before "modern" (the mid to late 1800's onwards) machine tools, you had people making a lot of things custom every time using files to get parts to mate together. There are some exceptions to this with specific measurement and manufacturing tools that were conceived and used but they weren't in wide spread use before the Industrial Revolution and they didn't look as similar to today's machines as everything after. We humans are really good at tweaking stuff slightly until it is far beyond the precision of the individual pieces itself.

Similarly, if I took any old lathe or mill, measured my part to be 0.100" and needed it to be 0.050", I could dial a cut in at 0.05" and take it but depending on the quality and rigidity of the machine, workholding, bearing surfaces and tooling, I would be hard pressed to hit that 0.050" dead on. However, I could take as many passes I wanted while remeasuring until I'm happy with the result. Cut 0.020" off, measure again, I should have 0.030" left but I actually have 0.027" left. Cut again this time at 0.010" and I should have 0.017" left but I have 0.015" left etc.

As others mentioned, the 3 plate method allows you to generate with time and effort, a very precisely flat surface. I could generate that surface, use it as my surface referenced plate and then hand scrape a piece to match it's flatness and squareness to the best of my willingness to work on it. https://en.wikipedia.org/wiki/Hand_scraper if you're unfamiliar. The craftsman inks (blues) up a reference surface, imprints the work piece by rubbing it on that surface. Only the points in contact touch. Using a scraper and some training, you can remove .0002" with a scraper cut. Remove all of the high spots that are blue bringing the high spots closer to the average. Remark and do it again iteratively. Each time you bring your work surface closer to your reference.

The same thing was done with precision lead screws. Hand made screws were cut with primitive methods and put in early lathe like machines to cut more screws. These machines had error compensation methods built in that averaged the thread cutting across the original screw (or sometimes multiple screws) resulting in a screw that was more precise than what you started with.

For calibrating a reference surface for flatness, you can use levels or autocollimators for overall variations. The precision of your level can be increased by increasing the longitudinal radius of your glass bubble dial.

An excerpt from another post I made in /r/cnc:
Some source material to consider:
LINK A great site with collections of documents covering major works in the development of precision tools.

Precision Machine Design - Slocum more of a textbook on precision machine design but has tons of footnotes and talks about some of the developmental history.)

Inventing Accuracy: A Historical Sociology of Nuclear Missile Guidance talks about some of the accuracy needed in Oakridge etc to help make the atomic bomb and precision guided missiles before GPS existed even for the military. A number of military interests drove ultra precision development such as this and the large optical diamond turning maching (LODTM)

Rolling Bearings and their contribution to the progress of technology covers the history of bearings that allowed precision machinery.

Machine Tool Reconditioning is an older book and highly technical but is considered the bible for old machine tool rebuilding and goes into the processes of how one would make precision flat surfaces and check all of the geometry on their machines and fix them in a time before lasers and fancy computer controlled equipment.

Foundations of Mechanical Accuracy and the followup book Holes, Contours and Surfaces was written by Moore and his son (I believe, respectively), the first especially is considered a bible on the theory of obtaining super precision tolerances. The authors are part of Moore Tool Company which made amongst other machines Moore Jig Borers.

Mitutoyo has a pdf on the history of gauge blocks

You can further go down that rabbit hole and look at metrology books as one can achieve great tolerances by iteratively approaching a desired value and having proper metrology equipment to check your work as you go. For example, metrology standards

You can also look at old professional telescope building books and newer diy telescope making books as there's a lot of interesting information and techniques to obtain precision optics on the order of wavelengths of light.

As someone else here mentioned: How Round Is Your Circle

I can probably dig up a lot more. I've spent way to much money purchasing old out of print books related to precision machinery, machining and metrology.

From the iterative process of making basic tools, you can then use those tools to make even better tools through iteration. In many ways, it's similar to Moore's law in the electronics world; a exponential curve where we stand on the shoulder of giants and improve upon what already exists. Many have proposed technology as a whole as just that such as Ray Kurzweil in "The Singularity is Near" etc.

Edit: Thanks for the gold!

In no particular order but all of the following are great.

• Skunk Works by Ben Rich - I reviewed it here
  
• Ignition! - It's an informal history of liquid rocket propellant and I did a more in depth review of it here
  
• The Design of Everyday Things - A book about how objects are designed. It changed how I look at the world and approach design. It took me few tries to get into it the first time.
  
• Introduction to Astrodynamics by Battin - A great textbook on the basics of astrodynamics that is both easy enough for undergrads to start, and rigorous enough to keep you interested as your math skills improve in grad school and later.

It's a big topic, and rocket engineering can't be summed in a reddit post. Buy yourself some books.

If you want more knowledge on the design and analysis of rockets, get a copy of Rocket Propulsion Elements By Sutton. (http://www.amazon.com/Rocket-Propulsion-Elements-George-Sutton/dp/0470080248/ref=sr_1_1?ie=UTF8&qid=1462063371&sr=8-1&keywords=rocket+propulsion+elements) - You don't have to buy the newest edition, thermodynamics hasn't changed.

I believe for vehicle design the best reference is SPAD (Space Propulsion Analysis and Design) (http://www.amazon.com/Space-Propulsion-Analysis-Design-Website/dp/0077230299/ref=sr_1_2?ie=UTF8&qid=1462063423&sr=8-2&keywords=space+propulsion+analysis+and+design) - Wow, that's more expensive than I thought.

Both books are intended for upper level college courses so you will need to learn other stuff too - like thermodynamics. But if you are interested in the subject then It will keep you motivated to learn the prerequisites as you go.

To start, learn the rocket equation, if you don't know it already. It is easy to do your first order analysis with just that, and add ~1km/s for air + gravity drag. Also, Wikipedia has an astounding amount of information. /u/danielravennest Wrote this wikibook, I haven't read it myself but he is always raving about it so you might find it useful.

Feel free to PM me. I am currently the lead engineer on a small bipropellant in-space propulsion system which is in early development.

Thermodynamics is usually covered separately from fluid mechanics. At least in chemical engineering, fluid mechanics is usually covered together with heat transfer and mass transfer, since they are all mathematically very similar, and can be grouped together as 'transport phenomena'. Fluid mechanics = transport of momentum, Heat transfer = transport of heat, mass transfer = transport of mass.

Anyway, if you are only interested in fluid mechanics, my favorite textbook is Middleman. For an entry-level textbook that covers all three, I like the W^3 textbook.

For more advanced transport phenomena, the de-facto standard is Bird, Stewart, and Lightfoot. A lot of schools actually use this for their undergraduate course, but I frankly think it's too difficult for an introductory text. For students that already know the fundamentals though, it's an excellent reference book.

For real graduate-level analysis, I really like Deen's book.

Caveat: all these textbooks are pretty expensive, and can run you close to $100 even used. There might be much less expensive alternatives that still teach the material well.

> let's say I want to do 5*5. How does it take 5, and multiply the same thing in binary

How this is done varies from processor to processor. MIPS are usually the easiest processor to understand. When I learned this stuff in school we started with MIPS. I work on ARM processors mostly now (smartphones), but at a high enough level that I don't worry about the type of details that you're asking now.

000000 00100 00101 00010 00000 100000

In MIPS, that binary sequence means add two numbers together. So if the CPU saw that binary sequence it would first look at the first six digits. This is called the op code. My memory to what these do exactly is fuzzy so I'll leave it to someone else to answer. The next five digits tell the CPU to grab the binary digits that it is storing in register 4, the next five digits tell the CPU to grab the binary digits it is storing in register 5. The next 5 digits tell the CPU that when it is done working with the numbers it should store the results in register 2. The next 5 digits are ignored for this example. The last 6 digits tell the CPU that it should add these numbers together.

If you previously stored the numbers 3 and 17 in registers 4 and 5, register 2 should now hold 20. (It's a different MIPS instruction to store a number, and yet another instruction to retrieve the number.)

I should note that most computer scientist never work at this low level of detail. If we want to add two numbers together and store the result we just type "a = b + c;". That would take the number stored in location b, add it with the number stored in location c, and then store it in location a. We wouldn't care if a, b, or c are registers or in cache or in ram. Those details are handled by the computer (well, compiler) not us.

As it how the processor adds the numbers together, ask a hardware guy. I don't really remember, and to be honest I never really understood it well either.

If you want to delve deeper into this subject, this is a good book, but be warned it assumes you already have a decent grasp of computer science.

As for the second part of your questions it has to do with the number of cores and what they specialize in. CPU's generally have just a few cores. Maybe 1 to 8. They are also general purpose so they can do a lot of things and are very powerful. This monster video card from AMD has 2048 stream processing units on it. None of those processing units are very powerful, and they can really only do a few tasks (which just so happen to be the ones that graphics need). But it can do 2048 of them at a time verses 1 to 8 on a CPU. That's the difference between a CPU and a GPU.

Take the Mythbusters example. Their "GPU" can only paint the Mona Lisa, nothing else. But it can paint it very fast. The "CPU" could be programmed to paint anything. It just takes a lot longer to paint it. Actually, that's a bad example. A CPU will beat a GPU at almost everything. GPU's can only do a few tasks, but the tasks they can do they are much better at than the CPU.

Thanks for the help.

I have started to just do a basic review of reinforced concrete columns and steel columns for now because it has been a few months since looking at them.

I had also thought about drawing the strain diagrams for the sections, but was unsure how the extra steel member in addition to the rebar would change the diagrams. Basically, my advisor wants me to create a program (either in Matlab or Mathcad) by the end of the semester that will calculate and draw the interaction diagrams for the columns when given the properties.

So far, my general steps that I have come up with are:

1. Determine properties of steel (Structural and Rebar) and concrete
   
2. Determine location of the centroid of the structural steel relative to the centroid of the concrete column
   
3. Solve for the stree/strain curves using a relative thickness of 1"(basically making the curves sort of stepped instead of smooth curves)
   
4. Solve for P, M
   
5. Solve for and plot interaction diagrams
   
   And my list of variables so far includes:
   
   
6. Steel Shape, size, and material obtained from AISCM
   
7. Rebar size and material (stirrup/tie sizes)
   
8. Bar spacing
   
9. Concrete (f'c, unconfined vs. confined)
   
10. Distance between centroid of steel shape and center of concrete column (both x and y directions)
    
    And I am assuming that:
    
    
11. Ec = .003
    
12. Clear Cover = 1.5"
    
    I will definitely print out that chapter as a reference. I don't currently have the money to buy that book, but I do own this book, this book, and this book and have access to everything in my university library. I'll check and see if it is there.
    

I highly recommend Ingenious Mechanisms for Designers & Inventors by Franklin Jones. It's about $120, but it is a four-volume set of hardcover books. I have it and I love it.

While you're on that page check out the "frequently bought together" links, there are some interesting titles there. I haven't actually read any of them, but they look interesting.

507 Mechanical Movements was the original (I think) from 1868. It's a fun book to flip through, especially since it's so cheap. There's a great website that has it all for free, plus well done animations for many of them.

There's also 1800 Mechanical Movements from 1899.

0.005" is a standard engineering tolerance, it is by no means "incredibly precise", you can do that with a WWII bridgeport.

An excellent resource for mechanisms of all sorts: http://www.amazon.com/Ingenious-Mechanisms-Designers-Inventors/dp/0831110848

Perhaps a local library would have one you could take a look at?

Failing that, there a lot of considerations going into a cam design. The acceleration of the follower is important. Having a ramp like you have drawn will make the follower want to skip off the cam at high speeds. You want to have smooth acceleration of the follower by having gradual ups and downs.

It would be easier to help with more information. How many followers are there? How fast does it need to go? How long does it need to last? What forces are involved?

As it stands the design you have posted would work with a roller follower and at slow speeds.

Unit Operations of Chemical Engineering by McGraw Hill and Perry's Chemical Engineering Handbook have the information on calculating heat transfer coefficients for heat exchangers. Heat exchangers can require itterative calculations if you're doing the calcs by hand. It's much easier to use software like HTRI

Though not really applicable to the engine side, and likely too conceptual for the tire wear models, this one is really good from the dynamics side and translates many aerospace concepts over to vehicle dynamics (Stability derivatives, etc.):

Race Car Vehicle Dynamics, Milliken & Milliken

Non-fiction, which to my mind makes it better:
The Soul of a New Machine

Also non-fiction and a great read, the autobiography of aircraft designer/novelist Nevil Shute: Slide Rule

My personal favorite is Manufacturing Processes for Design Professionals, which is sort of an overview and simultaneous deep dive into pretty much ever manufacturing process out there and how to design for it.

Introduction to Algorithms, also fondly known as CLRS, is pretty much the gold standard when it comes to an overview of algos.

edit: Amazon link if you're into that sort of thing.

I really enjoyed this book. It covers a few case studies of engineers solving problems with varying degrees of help from science/theory.

If you're a CompE, you're gonna be writing a lot of C. If you haven't read The C Programming Language, by Brian Kernighan and the late Dennis Ritchie, shame on you - it's one of the best, most helpful, and most concise programming books I've ever read. (The design of the book is a lot like the design of C, really.)

Also, if you want a reference for any algorithm you could possibly think of, I can guarantee it's in Knuth's Art of Computer Programming somewhere. CLRS, mentioned by xibernetik below, is another good algorithms book that's more accessible, but less in-depth.

The Design of Everyday Things by Don Norman

It won't make you an expert on good design but it's a good start.

Yes.

With a very large damping ratio

Practically, this means making a shock absorber (AKA a dashpot) with a very high viscosity fluid and a very small orifice.

There are other higher tech options too

The theory of mass spring dampers will be covered in any textbook on vibration.

Rao and
Thomson are probably the most popular. cheaper copies can be found on abebooks.com or other similar used bookstores.

You can try to find an extra long flexible retrival tool like this. Based on the pic you posted on the original thread it looks like you might be able to use it to get a grip on the edge of the phone case.

For something specifically focused on Engineering, anything by Henry Petroski

I particularly liked Invention by Design

Huh, still working on this, my inputs with the effort you've gone through.

1. What are the walls made of, is destroying a wall and repairing it an option? If this is a sheetrock wall, at this point I'd just go to the other side, cut through it, grab the phone and repair the wall.
   
   
2. Do you have something that can be stuffed between the wall to pull it up, I'm thinking something like a rubber ball on a coat hanger, force it between the phone and wall and then pull it up. An inflatable ball would be ideal
   
   
3. Don't use a coat hanger, use a fish tape, do you have one? can you get one? You would need to make it so it has a right angled bend on it so it can go under the phone and then pulled up. Maybe a U shape.
   
   
4. I would see if you can use a vacuum cleaner and get enough suction on it.
   
   
5. And the easiest thing (but last I thought of), buy this, now you're done.
   

Well not exactly a fiction book but as an engineer it is very interesting to read Invention by design by Henry Petroski.

Control Systems Engineering, 6th Ed, Nise

Modern Control Systems, 12th Ed, Dorf & Bishop

Automatic Control Systems, 9th Ed, Golnaraghi & Kuo

Control Systems Design: An Introduction To State-Space Methods

Control Handbook, 2nd Ed

Those are some that I have. The Nise book is excellent, the Dorf book is as well, it was my primary text for Controls I & II, supplemented by the Kuo book. The latter has more on digital controls. All of those three focus primarily on classical control theory and methods, but the Nise book goes into more depth on modern methods. I got the state-space methods book because it's more focused. The Control Handbook is a beastly collection, but it's very broad, hence not possessed of much depth. It's more of a reference than a text.

If you want to dive deeply into PID control, look no further than Akstrom and Hagglund's works on the subject, it doesn't get much better.

Source: I'm a degreed EE that specialized in control systems and a licensed control systems PE.

I studied computer Engineering with a focus on Computer Architecture

A good book for the more advanced topics is Computer Organization and Design

It jumps in at a fairly deep level, so you'd better already have a working knowledge of microprocessor architecture and assembly language, state machines, etc

Great place to start -- the Chem Eng bible -- Perry's Handbook:
http://www.amazon.ca/Perrys-Chemical-Engineers-Handbook-Edition/dp/0071422943

Any introductory structural design book will cover trusses. I would suggest starting there.

I liked the Hibbler book: http://www.amazon.com/Structural-Analysis-Edition-Russell-Hibbeler/dp/013257053X

I received this book for Christmas a few years ago and thought it was really cool.

Inviting Disaster by James Chiles. Every chapter is the story behind an engineering disaster. Some are the famous, major ones, like Chernobyl and Apollo 13, others are minor ones like an explosion at a nitroglycerin plant, and others were never disasters at all because good design and proper actions prevented a catastrophe. It feels like you're reading a novel, even as it's teaching you lessons about proper preparation and failure analysis. I highly recommend it.

I'd recommend you check out the book Inventing Accuracy: A Historical Sociology of Nuclear Missile Guidance (Inside Technology).

This has pretty crappy reviews, but it is worth a shot.

https://www.amazon.com/PF-WaterWorks-Ergonomic-Retriever-PF0408/dp/B01MT6CCI1

Machinery's Handbook

you cannot be a machinist without owning one of these

http://www.amazon.com/Machinerys-Handbook-Toolbox-Edition-Oberg/dp/0831128003

Vmax=(p•g•L^2 •sinΘ)/2•µ)

Where:

• Vmax is the maximum velocity of the fluid, should be the side of the film away from the wall
  
• p is the density of the fluid
  
• g is the gravitational constant
  
• L is the thickness of the film
  
• Θ is the angle of the surface in relation to horizontal, 90° in this case
  
• and
  
• µ is the viscosity of the fluid
  
  From Welty, Wicks, Wilson, & Rorrer pg. 95
  
  Should be able to rearrange that to get what you need.

Find the Milliken book. Aka, this one.

> Rocket Propulsion Elements
https://www.amazon.com/Rocket-Propulsion-Elements-George-Sutton/dp/0470080248

This book?

The Soul of a New Machine amazon link

We used these two for mechanical control courses:

http://www.amazon.com/Mechanical-Vibrations-5th-Edition-Singiresu/dp/0132128195

http://www.amazon.com/Feedback-Control-Dynamic-Systems-Edition/dp/0136019692

I can't remember the book we used for Linear Systems, but that was ECE.

I have had A History of Aerodynamics and Its Impact on Flying Machines by John Anderson in my queue for a while now. One of these days I'll get around to it.


What Engineers Know and How They Know It is another I'm curious about but may not get around to.


I've been working on October Sky--formerly known in print as Rocket Boys-- by Homer Hickam Jr lately. It's alright. I get a little distracted and put it down quite often. The A Song of Ice and Fire series was more captivating, but that's not surprising.

If your knowledge of control systems is limited to the frequency domain (classical controls) then you are missing out on quite a bit. You should look into time domain/state space controls to fill out your knowledge.

This is a decent book on it, and well priced.
http://www.amazon.com/Control-System-Design-Introduction-State-Space/dp/0486442780

I graduated within the past decade. I took a Manufacturing class - it was an elective. It included "lab" time that was spent in a machine shop. I also took a "Product Design and Rapid Prototyping" class - also an elective. Did some rapid tooling and other parts of product development.

I learned how to use a lathe, mill, etc. while at an internship (before I took that class).

The trend here - there was no requirement to learn how to use the tools that you may one day design parts for. I had to go out and do that myself.

> Also, can anyone recommend some resources for somebody looking to learn more about basic machining/manufacturing techniques?

I am shocked no one else has mentioned Machinery's Handbook.. That is the book for machining. Mfr techniques gets into the realm of DFM which is a little more in depth than knowing how to use a machine.

Inviting Disaster. Think about what you build, who you build it for, and how it can hurt them.