Posts tagged ‘mechanics’
Steel in Extremis
May 20th, 2013 at 9:00 am by Dr. Drang
I saw Iron Man 3 with my family Saturday night. It was fun (Ben Kingsley was especially good), but there was a part that bothered me a bit. I tweeted about it later: Iron Man 3 was fun, but that water tower in Tennessee should’ve fallen long before its leg melted.— Dr. Drang (@drdrang) Sat…
Now we see the violence inherent in Hooke’s Law
May 18th, 2013 at 10:31 am by Dr. Drang
This is the post where I explain how I avoided shooting my older son with the head of a screw. Two heads of screws, actually, but we’ll get into the details later. The underlying topic is strain energy, its potential1 for harm, and the respect it should be paid. As I said a few days…
Revisiting Castigliano with SciPy
January 6th, 2013 at 2:16 pm by Dr. Drang
On Friday, a colleague asked me if I had a quick solution for determining the spring stiffness of a tapered leaf spring. Yup. This may be the first time I’ve been able to use an old blog post directly for work. But as I read through the solution, I realized I’d done the numerical integration…
Programmers and physics
December 18th, 2012 at 11:32 pm by Dr. Drang
I’m sure it’s an age thing. Despite over 30 years of evidence to the contrary, I still think of programming as an adjunct to math and science, so I’m always shocked when I see things like this little writeup by Hannu Kankaanpää. It’s an explanation of how to write a program that tracks the motion…
Lego towers and the Menai Straits Bridge
December 7th, 2012 at 11:02 pm by Dr. Drang
You’ve probably seen this BBC News Magazine article on the maximum height of a tower of Lego bricks. I read it yesterday through a link from the indispensable Seth Brown (@DrBunsen), and was immediately reminded of this 1826 paper on suspension bridges by Davies Gilbert. That Gilbert paper is my white whale. I first saw…
Beams and potato chips
November 21st, 2012 at 11:57 pm by Dr. Drang
At Ryan Irelan’s request, @drdrang I really want to see a blog post about potato chips. — Ryan Irelan (@ryanirelan) Sun Nov 18 2012 9:47 PM CST here’s a post about the structural design of potato chips by way of Euler-Bernoulli beam theory.1 Let’s start with a straight prismatic beam. We use the word “beam” to…
Dynamics and fracture of Hunter Pence’s bat
October 24th, 2012 at 10:41 pm by Dr. Drang
If you didn’t see this Monday night, you probably saw a link to it later. It was the bottom of the third with the bases loaded for the Giants. Hunter Pence hit a broken-bat single through the infield that scored two earned runs and one unearned run on a misplay in the outfield. Giants went…
Mohr’s circle and the march of time
October 15th, 2012 at 12:06 am by Dr. Drang
A couple of months ago, I mentioned an analytical technique called moment distribution, a method that dominated structural engineering for most of the 20th century, but which doesn’t make much sense in a world in which every structural engineer has a computer. Back when I was a freshly minted assistant professor—before engineering students had computers,…
Large scale structural testing
May 11th, 2012 at 11:56 pm by Dr. Drang
I was kind of busy today, so I just saw this fun Boing Boing piece on the Constructed Facilities Laboratory at NC State. The post, written by Maggie Koerth-Baker, consists largely of a series of short videos from a tour of the lab given by its lab manager, Greg Lucier. The facility seems very nice,…
Jason Kottke and Theodore von Kármán
March 12th, 2012 at 11:05 pm by Dr. Drang
I’ve never subscribed to kottke.org’s RSS feed. I guess I figured that most of what Kottke links to gets relinked by others, so why bother. But today I followed a link there and poked around a bit, finally landing on this post about the edge of space. It struck me as being a perfect little…
