Forgot your password?
typodupeerror

Comment: Re:Looking for a Job (Score 1) 49

by Animats (#47923925) Attached to: The Case For a Federal Robotics Commission

Is it just me, or does this sound like an ambitious Law Professor looking for a new job as head of a newly minted agency?

Exactly the feeling I got. We don't even have an Federal Internet Commission, and don't seem to need one.

We do need to have the Consumer Product Safety Commission setting safety standards for the Internet of Things. They're properly the lead agency of safety issues. That will probably happen after the first few deaths due to cloud-based control of home devices.

Comment: Re:Of course you use force control to run fast. (Score 2) 87

by Animats (#47920041) Attached to: MIT's Cheetah Robot Runs Untethered

Pardon my ignorant question, but how is it a problem to have traction control? Wouldn't it be enough to glue traction strips to the feet or something?

That's like wearing shoes with golf spikes all the time.

Traction control for feet does roughly the same thing as automotive traction control for cars. The basic idea is to keep the sideways force below the break-loose point. This is the down force on the wheel times the coefficient of friction.

For car wheels, the down force is mostly constant. For a legged robot, it changes throughout the ground contact phase So the side force has to be actively controlled and changed throughout the ground contact. It's also necessary to compensate for leg angle.

Legs have an additional option. If a leg has three joints, you can adjust the angle at which the contact force is applied. This is a big win on hills.

I used to work on this stuff in the mid-1990s, but nobody was interested in building legged robots back then. It could be used for animation, but it was overkill for games. I never expected that DARPA would spend $120 million on BigDog. Robotics projects in the 1990s were tiny.

Comment: Re: Translation... (Score 1) 181

by bill_mcgonigle (#47918467) Attached to: WSJ Reports Boeing To Beat SpaceX For Manned Taxi To ISS

Fascism - aren't you paying attention? Since when is SpaceX selling weaponry - their brand of non-violent commercialism is harmful to the health of the State.

If I were Musk, I'd put up my own space station, if this goes to Boeing. I bet one with rotatational gravity and a zero-G hub is now feasible and commercially desireable. The hub can be arbitrarily long as long as the habitat area is decent for humans, lots of work can get done at the best cost and the zero-G area can be expanded modularly.

Comment: Of course you use force control to run fast. (Score 5, Insightful) 87

by Animats (#47915427) Attached to: MIT's Cheetah Robot Runs Untethered

That article is written as if that crowd invented running using force control. Of course you use force control. Everybody in the field knows that by now. I patented that 20 years ago. The Scout II robot at McGill, developed by Prof. Martin Buehler, used that approach. Buehler went on to become the designer of BigDog, but never got much public credit for it and quit to work for iRobot.

The key to legged running in non-trivial situations is careful management of ground traction. Traction is first priority, then balance, then foot placement. Historically, everybody worried about foot placement first, but that turns out to be backwards. As soon as you get off flat surfaces with good traction, traction control dominates.

The next unsolved problem in that area is not going fast. It's starting, stopping, and turning fast. Most of the legged robots accelerate very slowly, and don't make abrupt high-speed turns. Big Dog starts by trotting in place, then extending the gait out. Starting fast, stopping fast, and turning fast are all facets of the same problem. You have to take one stride using completely different control algorithms than you use for normal locomotion. That's all I'm going to say about this for now.

Comment: Clueless (Score 1) 59

by Animats (#47911665) Attached to: New Data Center Protects Against Solar Storm and Nuclear EMPs

This keeps coming up. The effects of an electromagnetic pulse and a solar storm are completely different. EMP is a big RF pulse with a risetime in the nanoseconds. This is a risk to input transistors connected to external wiring. Twisted pair, coax, and small mobile devices are relatively immune. Fiber optics are totally immune.

Solar storms induce DC voltages across long distances of conductive landscape. This is a risk only to transformers with grounded center taps connected to long transmission lines.

Here are the PJM power grid emergency procedures for geomagnetic events. They had to be implemented for a day two years ago. Almost nobody outside of power grid operators noticed.

Comment: Re:Like traffic tickets (Score 3, Insightful) 283

There was a story, I think on Slashdot, about cops who would go online and pretend to be sexually aggressive 13-year-old girls, luring in social misfits.

A lot of it seemed to be entrapment, that is, they trapped people into committing a crime who would never have committed a crime without the encouragement and manipulation of the cops. The entrapment defense has an unreasonable burden of proof.

That's not the kind of policing I would admire.

If Timmy said that Frank had been doing something heinous, then the cops could get a search warrant to arrest Frank and search his house and computer. They wouldn't need to trap him into exchanging child porn.

Comment: Re:So-to-speak legal (Score 1) 405

by hjf (#47908245) Attached to: Comcast Allegedly Asking Customers to Stop Using Tor

Hmm... I have this feeling we have a verbal contract for me to help you die. It's just that you can't deny it, since you're, you know... dead. This should definitely be a written and notaried contract.

A written, notaried contract doesn't say what the dead party's mood was at the time. It doesn't say if I bullied and blackmailed her for years and and broke her will. If I fucked up her mind so badly that she "freely" agreed to sign said contract.
If there are no laws on how a contract should be written, there will be no "notaries" to verify it, and there will be no legal framework to say that neither party can be drunk, or that a psychiatric test should be performed to prove that both parties are sane.
Government exists because evil people exist, and can do harm. It's there to protect us from these people. But us, the "good citizens", shouldn't let that good people get in government positions. The problem is: we don't care. And the evil people get in charge... and we all lose.

Comment: Re:So-to-speak legal (Score 5, Funny) 405

by hjf (#47907901) Attached to: Comcast Allegedly Asking Customers to Stop Using Tor

Oh, you're an idiot. You don't understand. It's not the Government God Damn Business to interfere on what I do!!! Any person should be allowed to engage into any sort of transaction with anyone else! It's a private contract between two entities!
If I want to pay my neighbor for mowing my lawn, why should the government get in the middle?
If I want to buy from comcast, I should have the right to do it if I please! I also have a right to terminate said contract whenever I please, and I can negotiate the price too.
If my neighbor wishes to die but she cannot kill herself, I could kill her provided we both agreed to!! It's our LIBERTARIAN RIGHT! If the cops find her dead, I should NOT be investigated. All I need to do is explain that we both had a VERBAL CONTRACT and that should be enough!
Cops shouldn't exist! Government shouldn't exist! I am a person and I should have the right to do anything I please with anyone, if we both wanted to.
Jesus. I don't understand the "extreme" libertarians like that. What will they do once they find out you can't really have a fair contract against a corporation (or anyone else) if there aren't laws or an arbitration system AKA "the judiciary system"?
Ah yes: The Free Market Will Solve All Those Issues®
(oopsie, no ® there. There's no government to ®)

Comment: Re:When the cat's absent, the mice rejoice (Score 1) 283

Unfortunately it's usually impossible to prosecute cops for misconduct. The only thing that has some small deterrence is throwing out the evidence (which the cop shouldn't have gotten in the first place).

http://www.nytimes.com/2014/09...
Challenges Seen in Prosecuting Police for Use of Deadly Force
By LIZETTE ALVAREZ
SEPT. 3, 2014
MIAMI — For decades, Florida has had a history of deadly, racially tinged police confrontations, many of them involving unarmed men, which have led to riots, protests and a steady undercurrent of rancor between minorities and the police. But in the past 20 years, not a single officer in Florida has been charged for using deadly force.

Comment: Re:When the cat's absent, the mice rejoice (Score 4, Interesting) 283

1) There is not a lot of evidence that most people who share this material are actually involved in harming children in any way.

18 years for trading child pornography?

I'll come out and say it, these laws are wrong. We have a higher incarceration rate than anyplace else in the world, rivaling Russia and China. Do you want to send those rates up even further?

I agree that child sexual exploitation is wrong. I think child pornography should be used as evidence for prosecuting the underlying crime. I can accept a reasonable criminal punishment for distributing child pornography, if that's the only way to send a message that our society strongly condemns child sexual exploitation. It seems that prosecuting people for having child pornography on their computers does more harm than good overall. I'm not convinced that prosecuting people at six degrees of separation from the underlying crime should be a crime itself. And I'm also not convinced that possessing child pornography created outside the U.S. should be a crime within the U.S. (Our bombs blow children to pieces in our many wars, which I think is a greater harm than their being sexually abused.) We don't prosecute web sites like bestgore.com that show beheadings and rapes.

But 18 years for trading child pornography is way out of bounds. That's the sentence we should give to somebody who originally abused the children to create the pornography, not someone at several steps removed who winds up with the images of it.

I think child pornography prosecutions are like traffic tickets. It's a lot easier for a cop to sit on his ass eating donuts in front of a computer monitor than it is to go out and prosecute actual sex crimes. And it would take a large shift in budget from uneducated cowboy cops to social workers, criminologists and social scientists who actually understand child sexual abuse and how to stop it.

http://www.sciencedaily.com/re...
Child abuse rises with income inequality
February 11, 2014
Summary: As the Great Recession deepened and income inequality became more pronounced, county-by-county rates of child maltreatment -- from sexual, physical and emotional abuse to traumatic brain injuries and death -- worsened, according to a nationwide study.

http://www.bmj.com/content/347...
Research: Preventing sexual abusers of children from reoffending: systematic review of medical and psychological interventions
BMJ 2013; 347 doi: http://dx.doi.org/10.1136/bmj.... (Published 9 August 2013)

http://www.miamiherald.com/201...
Florida spurns $50 million for child-abuse prevention

Computers can figure out all kinds of problems, except the things in the world that just don't add up.

Working...