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Comment: Re:Tesla needs just a few more things (Score 1) 300

by Guspaz (#46783749) Attached to: Mercedes Pooh-Poohs Tesla, Says It Has "Limited Potential"

Tesla has plans to add automated battery-swap stations to some of their superchargers. They've already demonstrated the swaps in a controlled environment (they put a battery swap station under a stage, drove a car on stage, swapped the battery, drove it off, drove another on, swapped it, drove it off), although it may have just been taking the battery off and putting the same one back on. All sedans they've sold to date are designed for battery swaps, and they plan to cost it out as an equivalent to what gasoline costs in the local market.

In terms of reducing peak loads on the grid, they do have plans to combine grid storage with solar panels (how convenient, Musk has SolarCity building solar deployments and Tesla building battery factories), with the goal of having the superchargers produce more power than they consume.

Comment: Re:Myopic viewpoint (Score 4, Interesting) 300

by Guspaz (#46783681) Attached to: Mercedes Pooh-Poohs Tesla, Says It Has "Limited Potential"

Tesla also plans to have cars in multiple price ranges; it sounds like they plan to have three within the next few years (the Model S, the Model E, and the Model X, and yes I realize the pun they built into the model names, they also trademarked "Model Y"). One of them, the Model E, is going to target that $30k price point (at least after rebates), although the reports are that the range will be in the 200-250 mile range rather than the 300-350 that their current top-end cars get.

In terms of increasing the range, that should improve gradually over time as the cost of battery cells go down. That was the point of the $5 billion dollar GigaFactory that they're building, to reduce the cost of lithium ion cells. The primary goal of that is to reduce the cost enough to hit the Model E's price target, but it also has the benefit of enabling higher ranges in the luxury cars where they can spend more money on the battery, albeit at the expense of weight. I know that they're working on longer-term solutions to improve range. They got some patents recently that relate to combining metal air batteries with lithium ion batteries in a hybrid power solution designed to circumvent some of the limitations of metal air batteries (they have the potential for higher densities, but have poor cycle life), although that stuff is a rather long way off.

In terms of ubiquitous fueling stops, they're working in that direction. They're hitting a steady pace building new stations, and by the end of 2015 should have most use cases covered between home-charging overnight and superchargers for distance drives. Automated battery swaps may help too.

Their success isn't a sure thing, but they're definitely making progress towards solving the problems.

Comment: Re:Myopic viewpoint (Score 2) 300

by Guspaz (#46783583) Attached to: Mercedes Pooh-Poohs Tesla, Says It Has "Limited Potential"

Musk has personally guaranteed the resale value of the Model S against any comparable luxury sedan. The "personally" part meaning that if Tesla goes out of business, he will still honour that guarantee. I presume that means if you sell it and are unable to get the guaranteed value, he'll make up the difference. As a result, if Tesla were to go bankrupt, you could avoid the liability by immediately selling your Tesla car and relying on the guarantee to avoid losing money on the deal. Of course, if ALL of his companies go under, you could still be in a fix, but this isn't 2008, and he's not strapped for cash.

Comment: Re:Yeah? (Score 4, Insightful) 300

by Guspaz (#46783555) Attached to: Mercedes Pooh-Poohs Tesla, Says It Has "Limited Potential"

Some of them are sort of valid, but not relevant in practice. For example, it's true that Tesla's current service infrastructure can't handle high demands... but that's because the infrastructure is sized for the current customer base. Building a service infrastructure that can handle many more customers than you actually have is a waste of money, and it's completely unnecessary so long as you continue to scale that infrastructure as you grow.

Comment: Re:power cars? technically no (Score 1) 165

by Guspaz (#46781001) Attached to: 'Thermoelectrics' Could One Day Power Cars

The Tesla car already has a bunch of shielding (both as a casing and to protect against impact damage) and cooling (active water cooling, specifically). Considering that most RTGs are designed to operate in a vacuum (where you have no medium to carry away heat) in zero gravity (where convection doesn't work), I have no idea what sort of cooling and shielding you'd require for terrestrial RTGs.

Comment: Re:power cars? technically no (Score 3, Insightful) 165

by Guspaz (#46775235) Attached to: 'Thermoelectrics' Could One Day Power Cars

1. I realize that they're currently at 5%, the whole point of my scenario was examining what sort of changes a large increase in efficiency would produce... that's the whole point of the article, after all. Efficiency would need to be somewhere around 50% to justify replacing ICEs with thermoelectric engines. Is that possible? I've got no idea, TFA gives zero layman-friendly information about what sort of efficiency improvements are foreseen.

2. Supply isn't as big a problem as the incredible safety issues. I acknowledge in my post that the idea is totally insane, which is why I doubt that, even with a big improvement in efficiency, you'd probably never see RTGs used outside of military applications.

3. That's not necessarily a problem. They conveniently provide power that can be used for active cooling. Cooling them in a vacuum is an issue (hence the giant heat dissipation fins), cooling them in an atmosphere isn't as much of an issue.

I suspect that sufficiently efficient thermoelectrics might find their way into military UAVs, which could remain airborn for extended periods of time, for example. Or as an alternative to shipping diesel to remote outposts (although they're currently looking into robotic trucks to solve that problem).

Comment: Re:power cars? technically no (Score 1) 165

by Guspaz (#46773931) Attached to: 'Thermoelectrics' Could One Day Power Cars

It's not as silly as you might think. I believe you get roughly 500W of heat per kilo of plutonium-238. A Tesla Model S driving at normal speeds consumes something like 15KW. If you could get 50% efficiency for your thermoelectrics, you could build an RTG-powered model S with 60 kilos of plutonium. You'd need capacitors for surge demand, obviously.

Of course, this would be completely insane, but I don't see why it's not theoretically possible, since the battery pack on the car that you'd be replacing already weighs something like 600 kilos.

Then again, with sufficiently efficient thermoelectrics, you might see the military using RTGs.

Comment: Re:Not a market back then (Score 1) 252

by Guspaz (#46772289) Attached to: Nokia Had a Production-Ready Web Tablet 13 Years Ago

While the marketing certainly played a big part in that, a bigger factor was likely that technology was finally ready. From the article, Nokia's tablet had a 4 hour battery life and weight more than four pounds... the bezel had 2.5x the surface area of the screen itself!

The thing wasn't a tablet, it was a portable Internet kiosk.

Comment: Re:Field of view (Score 1) 135

by Guspaz (#46708725) Attached to: A 2560x1440 VR Headset That's Mobile

I'm not talking about enhanced field of view by turning around (although that's definitely a bonus), but about the subtle sensations that enhance presence by having the small movements of your head reflected in terms of parallax changes and such.

3D displays work poorly for the use case that you describe, because they all assume that your head is perfectly still, facing the monitor, dead-centre. It doesn't account for any movement or different position of your head whatsoever(so it probably doesn't work for anything but the central monitor in front of you).

You will not get a sense of presence sitting in front of a bunch of monitors, even if they surrounded you in a circle. This is something that's difficult to describe to someone who has never tried modern VR headsets, because if you'd tried them, you would understand the huge difference between them. The feeling of feeling like you're actually in a game world, rather than looking at it through windows. Of standing next to a virtual character and having the same sort of sense of the person being there, being a certain size, in relation to yourself. A multi-monitor setup doesn't provide any sense of presence at all.

Comment: Re:Resolution is not the hard-to-solve problem.. (Score 1) 135

by Guspaz (#46708657) Attached to: A 2560x1440 VR Headset That's Mobile

Yes, varying the distance between the lens and the screen does the exact same thing on a display-based headset. The Oculus Rift sort of supports this today, by providing different lens cups. All the lenses that come with the Rift (the A/B/C lenses) are actually identical, the only difference is their plastic casing that varies their distance from the screen. It's possible that the consumer version will allow this to be fully adjustable rather than in discrete steps.

Comment: Re:Field of view (Score 1) 135

by Guspaz (#46704907) Attached to: A 2560x1440 VR Headset That's Mobile

Having experienced both VR headsets (with 90-110 degree FOVs) and the surround-yourself-by-lots-of-2D-monitors approach, throwing LCD monitors at the problem doesn't hold a candle to the immersion/presence the VR headset gets. There's more to experiencing presence than a big horizontal FoV. A VR headset also gets you the horizontal FOV, gets rid of gaps between monitors, blocks out stuff outside the monitors, provides you with stereoscopy, the head tracking gives you the possibility of parallax, etc.

Comment: Re:Beats the Glyph... (Score 1) 135

by Guspaz (#46704855) Attached to: A 2560x1440 VR Headset That's Mobile

Trading the screen-door effect for the rainbow effect isn't a good trade-off. The screen-door effect can be solved by increasing display resolution and tweaking sub-pixel geometry (DK2 is a diamond matrix pentile-like display that reduces the screen door effect), while a single-chip DLP solution can't do much to improve on the rainbow effect short of cranking up switching speeds (which are already in the thousands or tens of thousands of hertz).

For what it's trying to do, which is to simulate big screen without having to carry around a big screen, the Glyph can put up with some rainbow effect. For VR, it's a death sentence.

Comment: Re:what is different (Score 1) 135

by Guspaz (#46704831) Attached to: A 2560x1440 VR Headset That's Mobile

The stuff at affordable prices (still double what VR headsets will go for when the Rift or Morpheus launch) 10+ years ago was high-latency, low-detail/resolution, low-precision, bulky, with a tiny depth of field. The units that solved some or most of those problems cost tens or hundreds of thousands of dollars.

The two biggest things today are the much higher amount of compute performance available, as well as the existence of modern smartphone displays (small, high-resolution, low-latency), which didn't exist ten years ago.

Mathematics deals exclusively with the relations of concepts to each other without consideration of their relation to experience. -- Albert Einstein