How to Succeed in Motor Control: Olaus Magnus, Donald Rumsfeld, and YouTube

Jason Sachs December 12, 2016

Almost four years ago, I had this insight — we were doing it wrong! Most of the application notes on motor control were about the core algorithms: various six-step or field-oriented control methods, with Park and Clarke transforms, sensorless estimators, and whatnot. It was kind of like a driving school would be, if they taught you how the accelerator and brake pedal worked, and how the four-stroke Otto cycle works in internal combustion engines, and handed you a written...


Scorchers, Part 1: Tools and Burn Rate

Jason Sachs April 12, 20165 comments

This is a short article about one aspect of purchasing, for engineers.

I had an engineering manager once — I’ll leave his real name out of it, but let’s call him Barney — who had a catchy response to the question “Can I buy XYZ?”, where XYZ was some piece of test equipment, like an oscilloscope or multimeter. Barney said, “Get what you need, need what you get.” We used purchase orders, which when I started in 1996 were these quaint forms on...


Margin Call: Fermi Problems, Highway Horrors, Black Swans, and Why You Should Worry About When You Should Worry

Jason Sachs December 6, 20151 comment

“Reports that say that something hasn’t happened are always interesting to me, because as we know, there are known knowns; there are things we know that we know. There are known unknowns; that is to say, there are things that we now know we don’t know. But there are also unknown unknowns — there are things we do not know we don’t know.” — Donald Rumsfeld, February 2002

Today’s topic is engineering margin.

XKCD had a what-if column involving Fermi...


Basic hand tools for electronics assembly

Ed Nutter November 20, 20153 comments

Though the software tools vary with different microcontrollers, many hardware tools are the same.

If you are working on larger robotic or automotive systems, you will need a 3/8" and 1/2" drive socket set. There are occasions when even larger drive socket sets are needed. For small robots and taking things apart, the 1/4" drive socket set is useful. The sizes usually range from 5/32" to 9/16" and 4mm to 15mm.  You will need both shallow and deep sockets, both standard and...


Oh Robot My Robot

Jason Sachs June 26, 2015

Oh Robot! My Robot! You’ve broken off your nose! Your head is spinning round and round, your eye no longer glows, Each program after program tapped your golden memory, You used to have 12K, now there is none that I can see,  Under smoldering antennae,   Over long forgotten feet,    My sister used your last part:      The chip she tried to eat.

Oh Robot, My Robot, the remote controls—they call, The call—for...


Python Code from My Articles Now Online in IPython Notebooks

Jason Sachs May 1, 2015

Ever since I started using IPython Notebooks to write these articles, I’ve been wanting to publish them in a form such that you can freely use my Python code. One of you (maredsous10) wanted this access as well.

Well, I finally bit the bullet and automated a script that will extract the Python code and create standalone notebooks, that are available publicly under the Apache license on my bitbucket account: https://bitbucket.org/jason_s/embedded-blog-public

This also means they...


My Love-Hate Relationship with Stack Overflow: Arthur S., Arthur T., and the Soup Nazi

Jason Sachs February 15, 201551 comments

Warning: In the interest of maintaining a coherent stream of consciousness, I’m lowering the setting on my profanity filter for this post. Just wanted to let you know ahead of time.

I’ve been a user of Stack Overflow since December of 2008. And I say “user” both in the software sense, and in the drug-addict sense. I’m Jason S, user #44330, and I’m a programming addict. (Hi, Jason S.) The Gravatar, in case you were wondering, is a screen...


Book Review: "Turing's Cathedral"

Jason Sachs November 20, 20146 comments

My library had Turing’s Cathedral: The Origins of the Digital Universe by George Dyson on its new acquisitions shelf, so I read it. I’d recommend the book to anyone interested in the history of computing.

Turing’s Cathedral primarly covers the period in early computing from 1940-1958, and bridges a gap between a few other popular books: on the historic side, between Richard Rhodes’s


Practical protection against dust and water (i.e. IP protection)

Dr Cagri Tanriover July 5, 2014

Recently, I was faced with a challenge to provide IP65 compliance in a product that had to have humidity and pressure sensors on it. The tricky part was to keep the cost of the unit under $15 while meeting this requirement.

Under normal circumstances, one can put all the electronics within an IP65 enclosure that is affordable and readily available off-the-shelf most of the time such as the ones shown in this link. However, given the humidity and the pressure sensor need to be exposed to...


Musings on Publication — and Zero Sequence Modulation

Jason Sachs May 30, 20141 comment

Perhaps you don’t think about it, but in order for you to read these articles, someone has to do something.

And I don’t just mean writing them. Stephane Boucher has set up this website so that it’s automatic, for the most part — at least from my end of things, as an author. When I get an idea for an article, I open up a new IPython Notebook, write my article, save it in a Mercurial repository, run a Python script to convert from IPython Notebook format to HTML, open...


My Love-Hate Relationship with Stack Overflow: Arthur S., Arthur T., and the Soup Nazi

Jason Sachs February 15, 201551 comments

Warning: In the interest of maintaining a coherent stream of consciousness, I’m lowering the setting on my profanity filter for this post. Just wanted to let you know ahead of time.

I’ve been a user of Stack Overflow since December of 2008. And I say “user” both in the software sense, and in the drug-addict sense. I’m Jason S, user #44330, and I’m a programming addict. (Hi, Jason S.) The Gravatar, in case you were wondering, is a screen...


Levitating Globe Teardown, Part 2

Tim Wescott November 7, 20139 comments

Part 1 of this article was really more of an extended (and cynical) product review.  In this part of the article, I actually take things apart (sometimes a bit more suddenly than I meant to) and show you some innards.First the globe.  I knew there was a magnet in there someplace, because it's obviously plastic and it also attracts metal.  I had intended to gently part the globe at the glue bond along the equator.  I started by trying to gently flex the thing on my work...


Basic hand tools for electronics assembly

Ed Nutter November 20, 20153 comments

Though the software tools vary with different microcontrollers, many hardware tools are the same.

If you are working on larger robotic or automotive systems, you will need a 3/8" and 1/2" drive socket set. There are occasions when even larger drive socket sets are needed. For small robots and taking things apart, the 1/4" drive socket set is useful. The sizes usually range from 5/32" to 9/16" and 4mm to 15mm.  You will need both shallow and deep sockets, both standard and...


Oh Robot My Robot

Jason Sachs June 26, 2015

Oh Robot! My Robot! You’ve broken off your nose! Your head is spinning round and round, your eye no longer glows, Each program after program tapped your golden memory, You used to have 12K, now there is none that I can see,  Under smoldering antennae,   Over long forgotten feet,    My sister used your last part:      The chip she tried to eat.

Oh Robot, My Robot, the remote controls—they call, The call—for...


How to Include MathJax Equations in SVG With Less Than 100 Lines of JavaScript!

Jason Sachs May 23, 20146 comments

Today’s short and tangential note is an account of how I dug myself out of Documentation Despair. I’ve been working on some block diagrams. You know, this sort of thing, to describe feedback control systems:

And I had a problem. How do I draw diagrams like this?

I don’t have Visio and I don’t like Visio. I used to like Visio. But then it got Microsofted.

I can use MATLAB and Simulink, which are great for drawing block diagrams. Normally you use them to create a...


Margin Call: Fermi Problems, Highway Horrors, Black Swans, and Why You Should Worry About When You Should Worry

Jason Sachs December 6, 20151 comment

“Reports that say that something hasn’t happened are always interesting to me, because as we know, there are known knowns; there are things we know that we know. There are known unknowns; that is to say, there are things that we now know we don’t know. But there are also unknown unknowns — there are things we do not know we don’t know.” — Donald Rumsfeld, February 2002

Today’s topic is engineering margin.

XKCD had a what-if column involving Fermi...


Levitating Globe Teardown, Part 1

Tim Wescott November 4, 20133 comments

I've been kicking some ideas around for a long time for a simple and inexpensive platform I could use for control systems experimentation for the beginner.  I want something that can be controlled easily in a basic fashion, yet that provides some depth: I want to be able to present ever-more challenging goals to the student, that can be attained by fancier control algorithms all on the same device.

I'm currently looking at magnetic levitation.  It's fun, it has the potential to be...


Massive Open Online Courses ( Transforming education )

Jayaraman Kiruthi Vasan October 10, 20124 comments

Emerging trends in online education have opened up unforeseen learning opportunities for aspiring students. Eminent instructors from the best names in the industry such as Stanford, MIT and Harvard provide several courses with video lectures online.

Named MOOCs,  Massive Open Online courses are accelerating the learning process in a radical manner.  Online universities like Coursera, edX, Udacity, Khan Academy and Udemy offer courses which are professionally relevant.


Scorchers, Part 1: Tools and Burn Rate

Jason Sachs April 12, 20165 comments

This is a short article about one aspect of purchasing, for engineers.

I had an engineering manager once — I’ll leave his real name out of it, but let’s call him Barney — who had a catchy response to the question “Can I buy XYZ?”, where XYZ was some piece of test equipment, like an oscilloscope or multimeter. Barney said, “Get what you need, need what you get.” We used purchase orders, which when I started in 1996 were these quaint forms on...


Ideas to develop Embedded Devices for Smart Grid

Dr. Tayyar GUZEL October 28, 20111 comment

Wikipedia definition of smart grid is a type of electrical grid which attempts to predict and intelligently respond to the behavior and actions of all electric power users connected to it - suppliers, consumers and those that do both – in order to efficiently deliver reliable, economic, and sustainable electricity services. To enable such a system, information regarding the generation, flow and utilization of electricity should be collected from the grid, shared with all players in the...