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Comment Re:0.5 mm resolution (Score 1) 25

Also, they claim it is safe due to lack of radiation. But ultrasonic can fuck shit up too. I mean ultrasonic is currently used to break up kidney stones, shear and fragment DNA (for NGS prep).

Good points, but to be fair, ultrasonic is currently used to break up kidney stones because it is safe to use it to do so.

Comment Re:Dictators (Score 3, Informative) 55

The restrictions are a mix of reasonable nuisance management and paranoia about who is flying drones, what they can do, and chain of custody.

Beijing proper is a city with a population density of over 21,000 / km^2 -- so you can imagine the chaos if any tech enthusiast resident could fly a drone without a permit. Except for a couple of free zones in the outer boroughs, New York City restricts drone launcing and landings within the city to flights with a permit and flight plan, because otherwise the sky would be black with drones. Many cities -- both red and blue -- have zone restrictions for drone flights, and those currently hosting World Cup matches have tightened them for the duration of the tournament.

Comment Re:Congrats to Mr. Musk (Score 1) 315

...divorced from the grinding reality of regular folks.

What's the grinding reality of regular folks? I worked two jobs for years to put myself through college, got a job as an electrical engineer / firmware engineer (I've moved around a lot, working for some stable and some startup companies). I own a house and two cars, and work ~8 hours a day. Am I regular folk? Is my reality "grinding"?

I was able to buy a few shares of SPCX in the IPO, just for the hell of it. Now, as business builds, and Elon gets ever richer, so will I (a little). And, this is despite the fact that, YES, I AM regular folk.

Comment Re:I want to see inexpensive plugin hybrids but .. (Score 1) 135

You might want to read up on how current hybrid vehicles actually work, 'cause it seems you have more than one misconception going on.

I have. For instance, my latest vehicle is the Ford F-159 XLT,, the full-hybrid model of the F-series pickup truck line. Power train is:
  - 6 cylinder dual-turbo engine. (runs low power but approoximately doubles output when a lot is needed.)
  - 47 HP motor-generator "pancake" on the engine side of the ttransmission, to scavenge / return power to./from a 1.5 kWhr lithium battery.
  - 10-speed automatic transmission, working with the lithium battery;s main alternator to fine-tune match the engine/mogen to the current driving situation. Max power of engine plus hybrid mogen; 430 hp.
  - full four wheel drive.

So it's primarily a gas-engine power train with an electric-car motor mechanically coupled to the engine shaft. Many other hybrids, from the venerable prius onward, are similar, with plug-in variants having a big scavaging/peaking battery good for pure electric operation of tens of miles rather than a minute or so and a wall-powered charger added.

What I'm looking for is essentially a pure electric - totally electronic "transmission" consisting of alternator(s) between the batteries and the motor(s), plus a tiny engine-generator able to burn gas and feed some teens of KW of charging power into the batteries when running down the road or parked near it.
 

Comment cobalt chemistry, not so nice. (Score 1) 115

Do the Waymo batteries use one of the lithium chemistries including cobalt, or a non-cobalt chemistry such as lithium iron phosphate?

Cobalt chemistries have a higher power/weight and energy/weight ratio, which made them the go-to chemistries for vehicle batteries. But they also produce oxygen when the cells overheat, leading to an unextinguishable runaway fire hazard: A burning cell makes enough heat to ignite the adjacent cells, so the whole assembly of them goes. Bad enough when it's a car's worth, but a disaster if it's a shipping-container sized module of a utility energy storage site. (And even worse when the site is a building full of racks, which someone had "protected" from fire with water-spraying, equipment-shorting system, so the whole site burns up, as happened recently with one in California creating a toxic mess.)

That's why purpose-built stationary lithium energy systems use non-cobalt chemistries - heavier, but a shorted cell just kills itself without getting hot enough to light off its neighbors.

Comment I want to see inexpensive plugin hybrids but ... (Score 1) 135

I want to see inexpensive plugin hybrids.

But not like the current ones, which are primarily an engine/tranny powertrain with a motor/generator + small battery for scavenging downhill/braking energy for later accelleration/uphill/cruise/power-boost.

I want ones that are primarily a battery-electric with a small aux engine-generator (say 15-20 HP range), big enough to power crusing with a bit left over for gradually charging. That would let you range-extend by the size of your gas tank plus fillups (i.e. indefinitely if only gas is available) or go from battery empty to back on the road in a couple tens of minutes.

The backup engine would only run at max-efficiency speed and could use an atkins-like cycle (see "liquid piston engine") to get the max power out of the fuel. Most operation would use power-grid charging (when available and cheaper than fuel).

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