The most irritating part about a manual is the things it leaves unsaid:  they leave you wondering whether you’ve skipped essential stuff or whether you’re undereducated. Or both.

The Nastran manuals are remarkably well written, for the most part, but the nomenclature is often simply wild. And this makes it that much harder to follow the thread. Finite Elements is hard enough as it is!

A struggle – helped somewhat by many internet searches – to figure out how to enforce a displacement at the base of a structure (to simulate vibration testing) is the genesis of the brief tutorial that you can find (in PDF form) here. The notes outline enforced-displacement, enforced-acceleration and enforced-velocity – using the more “modern” method that consigns the large-mass method to the dustbin.

For some background on the theory, read Dr.Meher Prasad’s presentations (they’re at slideshare, here).

The effort to verify the solution is on, currently. I’ll update this post (or add another) after that’s done. Until then, view the results with some scepticism – as you must view the results of any simulation.

The tutorial’s been done using Hypermesh, and works with Radioss/Linear too since it uses the Nastran syntax

I’m probably reading too much into this comment by Carlos Ghosn (from an interview that you can I read here):

“I prefer a not-so-attractive car that sells well than an attractive car that sells less. People who are buying Logan are looking for a family car with lots of space and not necessarily for racing. However we take feedback from customers. Second generation of Logan would address concerns.”

Sounds to me as if Ghosn was saying the Logan is aesthetically challenged in the first place, and under-powered in the second. Describing it as a family-car (an unfortunate phrase that reminds me of that favorite malapropism of matrimonial ads – “homely looks”) only seems to take him one one step further down the road to calling it a weak pig, then smearing cheap lipstick over it.

To make things worse, they don’t seem to have been watching the market’s feedback closely enough. See the comments here. These date back to Nov 2008. And if this article in the Business Line 8 months later is accurate, it looks like whoops, back to the drawing board.

A designer once wrote:

Engineers tend to think of design as something added to a product. Less of it, surely, would reduce the cost of an entry-level vehicle.

That was Jerry Hirshberg, who went on to point out that design adds to the product’s value, not to it’s cost.

Yes, he was from Nissan. The key word is “was”. He retired in 2001.

Read this article for a little more about JH. The last para is plain marvellous:

I am not someone who is elitist about the design process or about design. We are all born creative. We reach our peak at age five. Then education and the workplace get a hold of us. And the people there inadvertently kill it–and do so while talking about how important creativity is.

Interested in industrial design and how designers worked at the Z cars? Check out the interview with Ajay Panchal and Diane Allen here, and some background on the heritage here.

For the man who green-signalled Hirshberg’s Z-car design scheme, Ghosn has come a long, long way. What price the gap between Allen’s “We didn’t want the car to be seen as cute, friendly or just handsome. The new Z needed to have somewhat of a sinister quality. ” and Ghosn’s “Family Car“?

Ghosn’s famous “frugal engineering” line itself, by the way, is nicely analyzed in this blog-post.

And no, it’s not just the Three Stooges who can mess up a job. Toss in cost-squeezing negotiations, move-risk-off-the-balance-sheet approaches, geographic distances and varying time-zones, linguistic and cultural differences and a few other similar ingredients. Heat and stir, and voila: you have one fine mess served up on a  plate of your choosing.

The Principles of Management course taught to us in our undergraduate engineering curriculum was woefully short of context. Examples like the Dreamliner mess should be a gift from god to teachers trying to emphasise these principles to aspiring geeks.

It’s widely documented – see it here, here and here.

It’’s the last that has a particularly arresting telling paragraph:

The company’s chief, W. James McNerney Jr., concedes that Boeing lost control of the process by farming out more design and production work than ever and not keeping close tabs on suppliers. He says the company is retaking control.

And even more educating:

“The idea was to get the risk off their books and get other people to do the heavy lifting for them,” Mr. Aboulafia said. “But the flaw was that led to a kind of ‘engineering light’ approach, and the problems on the 787 can be traced to that.”

“Engineering light” In an aircraft? That’s going to take some explaining to the students. And with an estimated 10 Billion Dollar overrun that’s some education.

The figure is from the article, whose author can be forgiven for rounding off accounting sums to a nice, resounding figure. You can read some  more gloom-and-doom on costs here, but there’s no arguing that Ten Billion Dollars has a nice weighty sound to it.

And Michael Crichton’s Airframe looks even more appealing as a must-read textbook for engineering students of courses like “Principles of Management”.

In a book (read it here) that’s starts with a lack of humility that we’d expect from anyone in finance these days, Andrew Lees argues that the productivity gains that the Western-World has seen are built principally around the exploitation of energy. And explaining how the availability of lower-cost skills in other countries provides a boost to profits, he writes:

The U.S. could therefore achieve a far greater energy subsidy by outsourcing production to the massive potential labour forces of Asia, than by trying to achieve productivity growth on its own.

Much of the logic in the book is compelling, though it’s principally about credit-crunches and not about the costs or benefits of outsourcing.

There are human costs, of course, to this urge to reap greater “energy subsidies” as related in this article in the New York Times. The heartbreak is that much harder to stomach when you read about the current Dreamliner mess. More about that in another post, but check out Andy Lees’ book linked above. It’s been a hard read for this engineer, but well worth it.