A Mad Engineer in an even Madder world

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ReBoot

I’m in SF. I’m working on something near three StartUps. The world is young, I am old, and it’s time the engineers do some serious damage. UpDates to follow soon.

-Cd

Portfoilo

I’ve launched a portfoilo to showcase individual projects.

It can be found below!

 

www.mad-engineer.com

TV Oscilloscope

A quick update on a random and fun evening.  A hall mate and a few friends from around Senior Haus showed up to tinker around with a TV we were disassembling.  One cool thing found online to do with a spare CRT is to drive the deflection coils with audio frequencies and make a cool visualizer out of the thing.  We did just that and had a grand old time messing around with Audacity and some music files.

The basic premise is pretty straight forward.  Take a TV cover off and check out the big tube inside.  Be careful not to break the tube (it can implode) or to short the capacitors on the flyback circuit (the one with the transformer and a line running to the back of the tube, where the electron gun lives) or touch the anode running into the tube near the screen, with the big high voltage line and the rubber coating and what not.  Now that you’re looking at the tube, find the terminals for the deflecting coils.  They’ll look like this:

These coils control the horizontal vertical deflection by generating a magnetic field and literally pushing the focused beam around.  Now that you have these terminals identified and some leads so you can do something fun with them, grab yourself an amplifier and run the leads into the output posts.  Join some speakers into the same posts, and find an input source for your computer.  Here we’re using a spare low quality amp and small computer speakers with a USB DAC hooked up via RCA, but an 1/8″ to RCA wire would work just fine as well.

With this, you’re ready to drive the channels with your laptop and some nice free software like Audacity to make some really spectacular things happen.  By driving the left and right channels, you can independently drive the horizontal and vertical deflections of the beam.  So you can do something simple like have the left and right channels be driven by a track, and you’ll get circles for in phase balanced music, and fun shapes otherwise.  Even more interesting is to drive the horizontal axis with a sawtooth wave and the vertical with a signal, say a square wave, and generate an oscilloscope image of what you’re dealing with.  Neat!  You also still get music output from the speakers so the whole thing makes for a cool system visualizer that is live and a bit different from what you’ll normally see.  When you don’t drive it, the beam sits centered on the screen at fairly high intensity, meaning the phosphor will be burned out fairly quickly.  In fact, the TV screen isn’t designed for this heavy of a load, so you’ll burn the phosphor fairly fast this way.  But CRTs are old and cheap, so no big loss.

Below you’ll see a picture of my hall mates watching the image kick on, the initial stand still beam, and a tracking sine wave.  Try it out!

Take care and enjoy kids!

Social Engineering

An engineer, just like any human being, sees the world through a filtered lens.  And while many an engineer act as if they have no bias, using only the purest of logic and reasoning to view all things, it is guaren-damn-teed that engineers are humans too.  With this thought in mind, I often consider the various distortions I give reality, the intricacies and subtle features I select as important to note and interesting to ponder.  And of course, as an engineer I often find myself resorting to what I find comfortable: a systems approach to abstract and often complicated interactions.

Recently I was at a very interesting talk by an IDEO designer who works on business culture.  IDEO has a location in Central Square just north of MIT, and my entrepreneurship course 6.976 headed up there to hear a few talks.  I had always considered designers very “floofy” and lacking in some hard discipline, but man oh man did this guy deliver.

His talk centered around the idea of the transition to an experience economy and how this should shape the work you do.  He began by giving a history of our evolving economical structure, stating that to begin with we were a communal economy, sharing our goods to survive.  However, as we became more wealthy we moved to a goods economy, where we fought for goods to satisfy everyone.  Eventually we became too wealthy for even this, and goods no longer represented us individually.  We began to transition to a service economy,where we purchased services to make our lives easier and happier.  Finally, he said, we have moved now into an experience economy, where services were no longer enough, and we now buy into an experience or an image to represent ourselves better.

This was all explained with a coffee example, stating that we used to grow the beans as a community and share them.  Then we started getting beans ourselves from someone who grew them.  Once this became universal, people bought ground beans from Folder’s.  After this, people bought into Starbucks and the experience they sold.  More examples of the experience economy were offered, showing updates people give on flickr or blog posts about the experiences they’ve had and their attempt to share this with you, which he claims is a further attempt to utilize services to spread these experiences.

I found this all to be incredible.  The ability of this designer to so quickly put his finger on a large, synthesized amount of data and convey accuracy and insight into the situation left me stunned and wanting for more.  Which was quickly delivered.

The designer spoke more about how at IDEO they want to know what’s coming next, after this experience economy.  His claim was to the shared experience that pops up in so many avenues.  He looks at events like flash mobs and communities like twitter wherein every user not only makes the experience better but is essential to the existence of the experience.  Websites like groupon.com also utilize this idea, and very successfully at that.

Again I was shocked at how well he looked at the world around him and observed a realizable and interesting insight.  I came to really respect this IDEO designer as a true Social Engineer, one who is able to observe complex systems and deduce ways to manipulate them to interesting and useful ends.  While I had always considered myself a fine Social Engineer, never failing (ahem) to network and information manage successfully with friends and cohorts, this man put me to shame with sheer talent at the discipline, going far beyond what I had considered and tapping into large scale implications and ramifications.  Inspiring, to be sure, and I’m left with many thoughts on how to better socially engineer a business or venture to be more successful by carefully feeling the market and people involved with the experience.

How do you utilize social engineering in your pieces?  I’ve always been wrapped up in the construction and implementation side, but never the use or experience.  Maybe that’ll be one of the last great skills I’ll wrap up in my career at MIT.  Moving beyond social dynamics engineering and into nonlinear social mechanics.  Too many engineers do forget the people involved in all this work, and now is as good as ever to step up and do some fun things with people.

Meccano Lava Lamp Centrifuge

This is an amazing hacked together centrifuge to test if a lava lamp would work on Jupiter after the guy had an argument with some coworkers at lunch.  The thrust bearing is so sketchy and I’m surprised it didn’t collapse and throw a piece through his walls, but nonetheless it is successful.  And I love the Android for reading G forces!

Anyways, check it out!

http://neil.fraser.name/hardware/centrifuge/

Steel Cast Mark 0

Today was, among many reasons, an excellent day.  After hardly sleeping, I awoke strikingly early to a warm spring morning, and had an early meeting with Hugh Herr, leader of the biomechatronics group over at the MIT Media Lab, where we talked about some work I could do for him that might be of some mutual interest.  I then immediately picked up some books for my American Revolution course, skimmed the relevant passages, and felt I knew enough to head to class.

And then promptly skipped the first half hour to do something AMAZING.  I’m taking 3.042 this term, a course focused on working an independent project as if you were an internal project in a company.  The project I’m working on is using 3D printed concrete to create molds for metal casting.  The problem, which you will see after thinking for a few, is that concrete melts at the temperatures of molten steel or other alloys.  This makes molding less of a useful thing and more of an exercise in futility.

Nonetheless, I skipped class to do the first step of our experiment for the day; a real live steel pour.  The tech my team is developing, see, is a ceramic slurry which can be slip cast onto the concrete mold.  As the slurry is poured into the mold, the concrete sucks out the liquid, pulling the ceramic particles in the slurry onto the surface of the concrete.  Once a thick enough layer is built, the remainder of the slurry is poured out of the mold, leaving a thin particulate ceramic covering the mold.  Firing the baby in a furnace sinters the ceramic, and a beautiful, thin, hard, high temperature coating is left on the mold.  I did this for about 6 different test pieces, using different soak times in the slurry to build different layer thickness, leaving several nice looking molds with our most successful ceramic layer to date on the surface.

I went to the rest of my classes and the magical hour of two finally came, when 3.042 starts and we could finish our experiment.  Now that we had a few sample molds with high temperature coatings, we did the only thing you can do with such a trite object, which is pour many pounds of 1600 degree Celsius brilliantly bright steel into them and pray the molds don’t explode.  The pour went fairly brilliantly, and we should have fairly good baseline data to push our experimental exploration in a solid direction.  All things considered, an ace day for an ace project.

Stay tuned, soon we’ll be CADing up all kinds of crazy shit just to make molds and cast it in various high temperature alloys.  Flywheels, hands, pretzels, whatever we can think of, we’re going to cast it and see what happens!  Whoo, Science!  No, not quite, ENGINEERING!

Till then,

Cody Daniel

3 Axis CNC Mill

Shoo!  I have not posted in a while.  This is most likely do to the retarded number of units going into my term.  But, I am having the time of my life, so it is most likely worth it.

These days I’ve been mostly working on my 2.72 project, which is the design and construction of a CNC desktop mill.  Most students in the course design a high precision desktop lathe, but our group decided the lathe had been done too many times and had too few design variables left over.  In light of this, we followed a senior student’s thesis for the professor, which was a small, easy to build CNC milling machine.

Boy, what a class.  I’ve learned more from this course than I have from entire terms, and we’re only a month into it.  In fact, our first design review is in several hours, and I’m somewhere between excited and completely boned, a pretty typical state for any MIT student at a checkpoint.  That being said I’ve got an extremely strong team, and I believe we’ll have this one on lockdown my friends.

Boy, real mechanical design is crazy fun.  First of all, I’ve spent the past two terms in electronics and materials land, so I’ve missed a lot of mechanical thinking.  Revisiting it all is great fun though.  An example is the error analysis of the machine, of which we need a nice list in about four more hours.  Error is anything that puts our cutting tool in the wrong place, and while you can never model everything, you can come close enough to be an engineer.  Our list so far includes the following:

Thermal growth

Vibrational modes

Bearing run out

Cutting tool collet run out

Stepper motor resolution

Lead screw play

Connection compliance

And needless to say the list goes on.  What’s fascinating is the true intensity of estimating any one error source.  Let’s just look at bearing run out on the cutting tool spindle.  In order to ensure the bearings don’t flop around, a pre-load must be applied equal to the manufacturer’s specifications.  This is usually 2-5% of the max load, so a pretty easy number to calculate and build in.  With that number present, we design a nut, spring washer and shoulders smartly such that a spanner wrench can be used to implement the pre-load exactly.  But the fun doesn’t end there!  As the machine makes a cut, the friction created by the pre-load heats up the bearings.  Further, operating speed alone creates bearing heat through friction, and taking a cut into material with the tool creates a lot of heat which carries through a variety of paths into the air and spindle.  All of this means thermal growth of the spindle and it’s associated pieces.  Thermal growth has to be allowed, as otherwise enormous pressures will be generated internal the shaft, utterly destroying it and the bearings.  So the thermal growth is expanded into the bearing pre-load, releasing the original compression applied across the bearing.  This means increased run out but decreased friction, rolling our heat generation off a bit but increasing vibration.  Somewhere, deep inside the math, exists an equilibrium point that the machine would truly run at.  But finding it is nigh near impossible.  And as engineers, we must have an answer for that which is not knowable, and we trudge forth with the tools we have and the knowledge of their limitations to find:  The Engineer’s Approximation.

So we FEA it, we run some empirical numbers on it, we examine a similar system, and we trust our gut.  And then we defend it to one of the best engineers in the world.  Just another day for an MIT student.

With all this in mind, I’ve mostly been doing modeling of the electronics system, because electronics and I get along real, real well.  That and most MechE kids don’t know a MOSFET from an op-amp, a real shame if you ask me.  I’ll rant at you about the horrors of the course 2 curriculum at MIT later, for now I’m going to do some saturation limits on a power transformer and bridge rectifier to supply our drive motor.

Expect some specs, diagrams, and how-to’s in the near future.  For now I’ve got to tool hard and hearty.

There’s now a full page following this project!  Check it out over at https://codydaniel.wordpress.com/cnc-mill/