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Comment: Re:A pencil? (Score 1) 561

by Rob the Bold (#46791597) Attached to: Ask Slashdot: What Tech Products Were Built To Last?

A mechanical pencil is a tech product?

Can you make one with stone knives and bear skins? But seriously, compared to having to "advance" the lead by grinding down the case of my primitive Ticonderoga, I thought my first mechanical pencil was a technological wonder.

And after all, we're talking about long-lasting technology. The longer it lasts, the older it gets, right? If someone were still using their great-great-grandpa's John Deere steel(!) plow bought from his blacksmith shop in Grand Detour, I guess that would win.

Comment: Overcollection (Score 2) 78

by Animats (#46791557) Attached to: How Nest and FitBit Might Spy On You For Cash

The trouble with these things is that they want to "phone home" too much. For energy conservation, Nest talks to a Nest, Inc. server and tells it too much. The info it needs (outside temp, power grid load status) is freely available from read-only web sites. (Given a ZIP code, the National Weather Service site will return info in XML.) But no, it has to talk to the "cloud" and give out personal information. That's totally unnecessary.

Comment: Re:HP Calculators (Score 1) 561

by Rob the Bold (#46791407) Attached to: Ask Slashdot: What Tech Products Were Built To Last?

I still use my HP-11C and HP-32S calculators at least weekly. They're now 25+ years old, and I've changed the batteries maybe twice.

Enter > Equal ..... Yeah!

My 11C and 32C (darn you and your extra memory, Mr. 32S guy. I shoulda waited.) still work, but alas, they are not working all that hard lately. I'm not sure I've ever changed the batteries in the 11C . . .

Comment: Teletype machines (Score 4, Interesting) 561

by Animats (#46789303) Attached to: Ask Slashdot: What Tech Products Were Built To Last?

I have several Teletype machines from the 1926 to 1940 period. All are in good working order. They're completely repairable; it's possible to take one apart down to the individual parts and put it back together. But they're high-maintenance. There are several hundred oiling points on a Model 15 Teletype. There are things that have to be adjusted occasionally, and manuals and tools for doing that. Every few years, the entire machine has to be soaked in solvent to clean off excess oil, then relubricated and adjusted. This is the price of building a complex machine good for a century or more.

(The Model 33 of the minicomputer era is not one of the long-lived machines. This was by design. The Model 35 was the equivalent long-lived, high-maintenance product; the 33 required little mainenance but had a llimited life.)

Comment: Eliminating buffer overflows (Score 1) 226

by Animats (#46789181) Attached to: Bug Bounties Don't Help If Bugs Never Run Out

The problem is C. Programs in all the languages that understand array size, (Pascal, Modula, Ada, Go, Erlang, Eiffel, Haskell, and all the scripting languages) don't have buffer overflow problems.

It's not an overhead problem. That was solved decades ago; compilers can optimize out most subscript checks within inner loops.

I've proposed a way to retrofit array size info to C, but it's a big change to sell. There are many C programmers who think they're so good they don't need subscript checks. Experience demonstrates they are wrong.

Comment: Re:Mercedes, BMW engineers are dimwits. (Score 2) 337

by Animats (#46783889) Attached to: Mercedes Pooh-Poohs Tesla, Says It Has "Limited Potential"

They saw diesel electric locomotives replace steam engines in just one decade in 1950s.

The reason was different. Diesels cost about 3x as much as steam locomotives pre-WWII. But by the 1950s, diesel engine manufacturing was a production line process and the price had come down.

The real advantage of diesel over steam was that steam locomotives are incredible maintenance-intensive. Here's daily maintenance. That's what had to be done every day, by a whole crew. That's just daily. Here's 120,000 mile maintenance, done about once a year for a road locomotive. This isn't an oil change; this is a full teardown, boiler replacement, and rebuild.

Electric cars don't have that big an edge over IC engines at this point.

Comment: Should we say hello? (Score 1) 217

by Animats (#46782353) Attached to: Kepler-186f: Most 'Earth-Like' Alien World Discovered

We could send radio signals that far, with the big dish at Arecibo. If they have intelligence, and radio, we can communicate with a 1000-year round trip time. Maybe we should transmit some of the proposed canned messages to other civilizations every month or so.

If there is other intelligent life out there, it looks like they're a very long way away. Too far to talk to round trip, even at light speed. None of the known extra-solar planets within a few light years look promising.

Comment: Re:Festo has been doing this for years. (Score 1) 36

by Animats (#46781831) Attached to: The Squishy Future of Robotics

Right. Traditional pneumatics is rather dumb - most of the time it's on/off, with air cylinders pushed up against hard limit stops. Positional control of pneumatic cylinders works fine, but it takes proportional valves, feedback sensors, and a fast control system. Until recently, industrial systems tended not to get that fancy.

I was interested in using pneumatics for running robots back in the 1990s, but the available proportional valves back then were big and expensive. One useful model of muscles is two opposed springs, and a double-ended pneumatic cylinder can do just that. You can change both position and stiffness, separately. You can simulate a spring, and recover energy. Someone did that at CWRU a decade ago, but the mechanics were clunky. Festo does that elegantly with their new kangaroo. Very nice mechanical engineering.

Shadow Robotics has a nice pneumatic robot hand. Shadow has been doing pneumatic flexible actuators for many years, but now they have good controllability.

Comment: Festo has been doing this for years. (Score 5, Interesting) 36

by Animats (#46777325) Attached to: The Squishy Future of Robotics

Every year, Festo, the German robotics company, builds an exotic new kind of robot as a demo. Many of their robots have been "soft".

Here's their whole list of experimental projects. They've been doing "soft robots" since 2007. Others were doing "soft robots" before that, but the control usually wasn't that good. Festo builds soft robots with smooth, precise control. Festo's specialty is precise control of pneumatic systems, so they know how to do this.

Comment: E = (T2-T1) / T1 (Score 3, Informative) 172

by Animats (#46773857) Attached to: 'Thermoelectrics' Could One Day Power Cars

E = (T2-T1) / T1

Everyone with an engineering degree knows this. Trying to extract much energy from low-grade heat at the output end of an engine is inefficient. This was figured out a long time ago. Here it is in The Manual of the Steam Engine. It's possible to increase steam engine efficiency by compounding, where the exhaust from each cylinder feeds a larger, lower pressure cylinder. This is cost-effective up to about 3 cylinders ("triple expansion"). Engines up to quintuple-expansion have been built, but the additional power from the last two cylinders in the chain isn't worth the trouble.

Comment: Re:When will they gentrify the Tenderloin? (Score 1) 356

by Animats (#46773391) Attached to: San Francisco's Housing Crisis Explained

In 2005, this appeared in SF Weekly, about the gentrification of the Polk St. area of the Tenderloin:

Gay Shame calls the Lower Polk Neighbors Association a "brutal gentrification squad" of wealthy business owners, slumlords and bureaucrats.

"They are trying to transform Polk Street from the city's last remaining gathering place for marginalized queers and street culture into a hip destination for wealthy suburbanites," Mary said. "We want a safe place for marginalized people, and Polk Street has historically been that space.

"The neighborhood may soon be known more for green-apple mojitos and stretch Hummers than trannies and tweakers (methamphetamine users)."

That was back in 2005. Gentrification won.

Comment: Re:Are you kidding (Score 2) 797

by Rob the Bold (#46766523) Attached to: Study Finds US Is an Oligarchy, Not a Democracy

I have no sympathy. In fact, many of you cheered it as a sign of greatness and freedom that America was doing this. Your allies, however, were fucking appalled. Let

Let me finish that sentence for you:

Option 1: "Let me just say that I laugh at your situation, secure in my knowledge that nothing like that can happen where I live."

Option 2: "Let me see this as a warning that despite rule of law, foundational documents, and all the trappings of representative government, this could still happen here. I will be especially on guard against those that try to subvert my country."

Comment: Re:When will they gentrify the Tenderloin? (Score 3, Interesting) 356

by Animats (#46764379) Attached to: San Francisco's Housing Crisis Explained

It's happening. First, take a look at a map of the Tenderloin, from "Areas to Avoid, San Francisco." Twitter HQ is in that area, between 9th and 10th on Market, and the long-standing "mid-Market area" around there is rapidly being rebuilt. In fact, just about everything south of McAlliister has been gentrified, except for parts of 6th St and a small section around 7th and the north side of Market. Rebuilding is underway along the Van Ness corridor too, and has more or less chopped a block off the Tenderloin on the west side. That's the old "Polk Gulch" area, once a gay rent-boy hangout.

So the SF Tenderloin is about half the size it was a few years ago. Progress continues.

The test of intelligent tinkering is to save all the parts. -- Aldo Leopold

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