Forgot your password?
typodupeerror

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: Teletype machines (Score 4, Interesting) 562

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:McArdle is astute (Score 1) 25

by mcgrew (#46787089) Attached to: Obamacare is Not a Single-Payer Conspiracy [Bloomberg]

What worries me about her is that she was in charge of Clinton's single-payer plan, and screwed it up royally. So far I don't like any of the candidates from either major party.

Either way I'll probably vote either Libertarian or Green. I cannot support a candidate who wants me in prison. The only way she'll get my vote is if the Republicans screw up in their Presidential nominations like they did with Illinois' Governor's race. They had one excellent candidate, two acceptable and a tea party billionaire who hates unions and middle class people. They chose the only candidate who could get me to vote for Quinn.

Morons. They'll probably nominate another tea party stinker who only cares about the 1%. If they do I'll have to vote for Clinton.

User Journal

Journal: Mars, Ho! Chapter Sixteen 2

Journal by mcgrew

Pressure
When I woke up, all my muscles were on fire. We would have had to turn the ship around today, and in fact that's what was scheduled, except for the meteors and the drama that followed.
Destiny was sleeping peacefully. I got up, thankful that we weren't at Earth gravity but wishing we had turned around for deceleration then, because they have it plotted so that you start the journey close to the planet you're leavi

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: Re:McArdle is astute (Score 1) 25

by mcgrew (#46778449) Attached to: Obamacare is Not a Single-Payer Conspiracy [Bloomberg]

However, if there is anything in which I have confidence, it is this administration's commitment to slow, methodical, blame-laden screwings of the lower- and middle-class.

In what way has the lower and middle class been screwed by the present administration? I'll agree that the previous administration was great for the rich and crappy for everyone else, but I posit it's slowly improving.

The lower and middle classes have been getting royally screwed for at least half my life, and I retired earlier this year. The screwings started with Reagan's Capital Gains cuts, which caused an orgy of hostile corporate takeovers leading to layoffs and lowered hours. I was hurt badly when my employer staved off an attempted corporate pirate raid.

No, that suppository arrives with the Clinton Administration. I reckon she's wreckin'.

I certainly hope so, it would be nice for the US to raise to the level of the rest of the industrialized world from our historically barbaric health care "system". American health care is far from #1 in any measure except cost; ours is the most expensive. It's neither logical nor rational.

As to Clinton, if she's elected and half as good as her husband the country will be in fine shape. It would be incredibly hard for her to be anywhere as bad as George Junior, the worst President in my lifetime (AFAIC we've really only had two good Presidents in my lifetime, Eisenhower and Clinton, and as I was very young I could be wrong about Eisenhower but love that interstate highway system, as well as his cautions about a military industrial complex).

I'm more worried about Illinois. Dillard was Chief of Staff under Thompson and Edgar, and Illinois did pretty good until Ryan got in, and it deteriorated worse under Blago. It hasn't gotten much better under Quinn, but unfortunately Dillard lost the primary and the stupid Republicans nominated the only one of the four candidates that would get me to vote for Quinn.

Comment: Well said. (Score 1) 1

by mcgrew (#46778141) Attached to: Lies, damned lies, and ... oh no, you're going there.

Liars always lie. I think people mistrust statistics because they don't understand statistics, or worse, understand a little, just enough to be dangerous.

I worked with data and statisticians my whole career. I'm not a statistician, but learned a lot about the discipline from working with them. One of my co-workers had written a textbook on the subject that was used in colleges. Very interesting discipline.

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.

It's later than you think, the joint Russian-American space mission has already begun.

Working...