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Comment Re:Of course you use force control to run fast. (Score 2) 90

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 Of course you use force control to run fast. (Score 5, Insightful) 90

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

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 Only Apple can't make sapphire work. (Score 0) 207

Everybody who gets an iPhone immediately puts it into a rugged, generally rubberized, case.

That's pathetic. All that effort to make a super-thin device, and you have to put it another case to protect it. Nokia would laugh.

Get a non-toy phone.

It's amusing that Apple can't get sapphire-coated glass to work. Sapphire glass for checkout scanners is a standard product. Every Home Depot checkout scanner has sapphire-coated glass. People slide metal tools across those for years without damage.

Comment Voice operation of smartphones sucks (Score 1) 326

The smartphone crowd assumes they own the user's eyeballs. They don't. What's needed is better voice integration. You should be able to call, receive calls, text, and receive texts via a Bluetooth headset with the phone in your pocket.

Android sucks at this. My Samsung flip-phone had better voice dialing than my Android phone. Wildfire, which is from 1997, did this quite well. But it was really expensive to do back then, and was priced as high as $250/month. Then Microsoft bought Wildfire and abandoned the product.

Comment A secular morality that once was popular in the US (Score 4, Interesting) 937

Business used to have a completely secular moral compass. Rotary International has their The Four-Way Test, a "nonpartisan and nonsectarian ethical guide for Rotarians to use for their personal and professional relationships." Rotarians recite it at club meetings.

Of the things we think, say or do

  • Is it the TRUTH?
  • Is it FAIR to all concerned?
  • Will it build GOODWILL and BETTER FRIENDSHIPS?
  • Will it be BENEFICIAL to all concerned?

This is a morality for business. That's a concept that sounds archaic today. It was mainstream from about 1940 to 1975. Many small business owners used to belong to Rotary, especially in small towns. What went wrong? That's a long story, and has to do with the decline in the political power of small business.

Anyway, that's a completely non-religious moral system which is still around and once was mainstream.

Comment High-power industrial civilization may not last. (Score 5, Insightful) 196

Records of human civilization go back over 3000 years. Industrial civilization goes back less than 200. A good starting point is the opening of the Liverpool and Manchester Railway in 1830, the first non-demo steam passenger railway. There were earlier locomotives, but this is the moment the industrial revolution got out of beta and started changing people's lives.

Only in the last 80 years or so has human exploitation of natural resources been able to significantly deplete them. Prior to WWII, human efforts just couldn't make a big dent in the planet. Things have picked up since then.

There are lots of arguments over when we start running out of key resource. But the arguments are over decades, not centuries or millenia. The USGS issues mineral commodity summaries. There are decades of resources left for most minerals, but a lot of things run out within 200 years. Mining lower and lower grade ores requires more and more effort and energy. For many minerals, that's already happened. People once found gold nuggets on the surface of the earth. The deepest gold mine is now 4 miles deep.

For many minerals, the easy to extract ores were used up long ago. Industrial civilization got going based on copper, lead, iron, and coal found in high concentrations on or near the surface. All those resources were mined first, and are gone. You only get one chance at industrial civilization per planet.

Civilization can go on, but it will have to be more bio-based than mining-based. Energy isn't the problem; there are renewable sources of energy. Metals can be recycled, but you lose some every round. It's not clear what this planet will look like in a thousand years. It's clear that a lot of things will be scarcer.

(And no, asteroid mining probably won't help much.)

Comment Re:What's the angle? (Score 1) 35

Great question. We are seeing a lot of interest among enterprises to have AWS-like functionality in their own datacenters. And we also know that they are eager to use OpenStack. So at Eucalyptus we decided to do something about it. Here is my blog about the topic: https://www.eucalyptus.com/blog/2014/08/11/why-eucalyptus-keynoting-openstack-conference

Comment Re:'terminal in a library' (Score 1) 102

Define 'in'.

"In" means at an "dedicated electronic reading point" in a publicly accessable library. Not necessarily the library that contains the paper copy. The main restriction is that libraries may not use this to reduce the need to buy multiple copies to satisfy demand.

This is great for scholars who really need to see some obscure published paper from 1982, and are not near a huge academic library. It's great for people who like to read out of print novels. It won't do anything for people who want to read the latest best-seller when all the library copies are checked out.

Comment Trolley buses. (Score 1) 491

San Francisco still has trolley buses. They're powered from a pair of overhead wires. The current generation of buses also has some battery backup, so if they lose their trolley connection while turning, the bus can get back under the wires on battery power and reconnect.

They're a pain. Too much overhead wire, and limited routes. NYC got rid of overhead wire a century ago, which was a really good move. SF has these mostly because, at the beginning of the bus era when other cities were converting from trolleys to buses, Diesel buses lacked enough engine power to climb the hills.

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