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Comment Re:XKCD Predicted this (Score 1) 47

The sad thing is that Spirit could still be with us today too if things had played out differently. When Spirit got stuck a lot of their early attempts to get out so that they could get to a good wintering grounds were in vain. However, right near the end they came up with a clever way to "swim" the wheels through the sand and were nearly out when winter hit and they had to leave it in a poor location... where it failed to wake up the next spring, most likely due to excessively low internal temperatures.

Curiosity is great, but the cost of Curiosity-style rovers is just so high. When I think of all that could be done with the Mars 2020 budget (Curiosity-style clone).... ugh. I would have rathered they make incremental improvements to a Spirit / Opportunity style design than a Curiosity one. Maybe more / larger radiothermal heaters so that they're not as cold-sensitive and improved wheels and flash storage, for example. Get their price down to ~$350M USD per mission (from $410M/rover for Spirit & Opportunity) rather than 2,1 billion USD per mission (aka Mars 2020, down from $2,5M for Curiosity). Send a new pair for $700M with new sets of instruments to new areas, save $1,4 billion, and put, say, $800M toward a new Titan mission and $600M to a new Venus mission.

I just don't like how Mars keeps becoming more and more of a money pit that sucks the funds from exploration of every other part of the solar system.

Comment Re:Headphone Jack is Pretty Crappy (Score 5, Insightful) 448

Indeed, I've never had a modern 3,5mm headphone port wear out. I've had a lot of micro-USB ports wear out. : And it's only logical that would be the case, the electrodes on the headphone port are far more robust than those on a micro-USB port.

I know that the standard response to "3,5mm port removal is the feature that nobody requested" is "it'll be painless and we'll be able to use the extra space to more useful internal hardware without having to make the phone bigger". But just ignoring the "painless" thing... how much more "capability" can you add in such a little space? That's enough for what, maybe 5% more battery time?

Maybe I'm wierd, but I couldn't give a rat's arse how thick a phone is... I just want it to be robost and not a big headache.

Comment Re:Much better source of Hydrogen (Score 3, Interesting) 71

There's actually a plausible case for bringing hydrogen back from Venus (not Jupiter) - it's highly deuterium-enriched (~150-240x Earth) due to the great amount of hydrogen loss to space over the planet's history. If further enriched in-situ (using the local abundant energy resources), it could be exported back to Earth. And there's a pretty clever way to do in-situ enrichment as well: whatever facility you're operating is going to need nighttime energy storage. Electrolysis has a very strong enrichment factor. If you wire your fuel cell stack in a cascade, you're enriching the deuterium at the same time you're storing electricity, and hence getting it for "free" (only the cost of the cascaded plumbing versus a simpler linear approach). There's also potential for enrichment on the recombination side.

Exporting from Venus is (obviously) not economically viable at present, however; you need the total costs to get the return product** to be under $1k per kg. ~$2k/kg if you had to return some hydrogen-bearing material anyway (such as plastic containers) and returned deuterated versions instead. But there could well be a potential case in the distant future for importing hydrogen.

** Costs include in-situ propellant (and potentially drop tank) production for launch, fueling the cycler, deorbit costs at Earth, and of course maintenance of everything involved, not least capital cost amortization if you want to be fair.

Submission + - Laser-Armed Martian Robot Now Vaporizing Targets Of Its Own Free Will

Rei writes: We know now that in the early years of the twenty-first century this world was being watched closely by intelligences granted by man and yet as mortal as his own — intellects vast, cool and unsympathetic, regarded this earth with envious eyes and slowly and surely drew their plans against us. Or at least one can assume that's what's happening on Mars these days, as NASA — having already populated the Red Planet with robots and armed a car-sized nuclear juggernaut with a laser — have now decided to grant fire control of that laser over to a new AI system operating on the rover itself. Intended to increase the scientific data-gathering throughput on the sometimes glitching rover's journey, the improved AEGIS system eliminates the need for a series of back-and-forth communication sessions to select targets and aim the laser.

As a side note, may I be the first to add that I think Curiosity is a lovely name, I love what you've done with the planet, but I have a medical condition that renders me unfit to toil in any hypothetical subterranean lithium mines...

Comment Re:New kind of pickup truck? (Score 1) 171

If you wanted to take it to extremes, you'd get something along the lines of a larger, heavy duty Aptera. Although for a pickup that's probably going a bit far. ;) At the very least, you need some depth on the rear end, and some degree of rear wheel spacing for load stability.

Re: rollovers, however, EVs are naturally resistant, because you keep the batteries on the underside of the vehicle.

One of my more extreme concepts is to have all of the wheels as self-contained, independent azipods, each with their own motor and battery pack (battery pack in the taper behind the wheel). That way not only does the center of gravity stay absurdly low, but you get rid of all of the long linkages, shorten your wiring runs (less losses, among other benefits), and have the possibility to doubly-isolate the cabin from vibration and noise (once in the motor/wheel linkage, and once in the pod-cabin linkage, perhaps a cable-isolater for the latter). Better vibration isolation lets you run with harder, more efficient tires (potentially even non-pneumatic). Also, keeping the batteries in the pods would reduce the amount of power you'd need to run through the azimuth mount; mounts with power transmission are available, but they get pretty bulky, large, and heavy when you start talking about the peak power needs of an EV. Instead, you'd only transfer what you need to for charging and load balancing (the cabin would have its own small pack for accessory loads). There is a downside, mind you, which is that they submerge easier in deep water; however, you could run a flexible air tube through the core of the pod mount and basically have them "snorkeled". While there are waterproof motor mounts on the market (designed for boats and submarines and the like), I rather like the idea of having the cooling air exhausted through the (low clearance) rotor opening, maintaining constant positive pressure sufficient for a couple meters of depth. I'd love some of the compact pancake motors that you find on the market, like the EMRAX series. Four of those and the bloody thing could fly if one mounted props instead of wheels ;) .

Some day I'll have the right combination of free time and budget to experiment. I usually have either one or the other but not both ;)

Comment Re:New kind of pickup truck? (Score 1) 171

They do the "engine compartment" to be an crumple zone. You know, little thing called safety

65 mph = 105 kph = 29 m/s
Let's limit deceleration forces in an accident at those speeds to the human limit (around 100g).

a = -100G = -100 * 9,81m/s^2 = -981 m/s^2
v1 = v0 + at
0 = 29 + -981 * t
981t = 29
t = 0.03

Average velocity during deceleration = 29 / 2 = 14,5
0.03 * 14,5 = 0,42m = 1,3 feet.

No, you don't need vast distances to make highway-speed crashes into a brick wall survivable. Furthermore, that's not real-world crashes in the vast majority of cases. The other vehicle gives as well. And the more rounded the front end and the more the structure is designed to do so, the more the vehicle attempts to deflect

The key aspect is that you need the passenger safety cell to not be penetrated and the combination of airbags and seatbelts to provide a steady, smooth deceleration that prevents harsh impacts. In terms of crumple zones and deceleration, the long front on a conventional car is hindered by its contents. A large amount of the volume inside is taken up by effectively uncollapsable or poorly collapsible hardware - e.g. an engine block isn't going to flatten into a pancake in an accident Do a google search for "fatal car crash" (if you can stomach it) and look at what percentage of the hoods are actually crumpled in on front-end collisions. It's often surprisingly little. The real killers are failed safety cells, not G-forces. It's hard to make the passenger compartments tolerate the forces survive for a number of reasons - for example, the A-pillars need to be narrow so as not to block one's view.

To put it another way: You may have 10-20 centimeters between your body and the outermost point on a car in a collision, versus a couple meters on the front end. And the human body tolerates lateral G-forces worse than front-on. If a highway speed crash was likely to kill you due to G-forces, then even a tiny tap on the side of your car should kill you. (front-on collisions are more survivable, but not that much more!)

Comment Re: So funny (Score 1) 171

Look at the financials. Tesla will go bankrupt soon.

You're of the strange view that there's something preventing Tesla from doing rounds of equity financing, the standard for a rapidly growing company (virtually all new companies go through repeat financing rounds, and continue to do so until their growth tapers off). Something Tesla has done many times in the past, and something that they've always gotten strong interest in the past, with much weaker demand lined up than that for the Model 3.

At some point Tesla will fill its market niche, stop growing, and no longer be able to make use of equity financing. With several hundred thousand pre-orders on hand to fill, they're far, far from that point.

Comment Re: So funny (Score 3, Interesting) 171

SolarCity isn't pretty revolutionary. But SpaceX and Tesla's work has been pretty revolutionary. No, it's not like SpaceX "invented rockets" or like Tesla "invented electric cars". But they did vastly change the paradigms in both regards and turn a bunch of new techniques / technologies from the kit / niche / hypothetical arena into mainstream production, as well as radically altering public perceptions..

I'm not sure why people don't see that as commendable.

Comment Re: So funny (Score 5, Insightful) 171

Yeah, why does he keep saying he can do things and then actually doing them? What's wrong with the guy?

"I'm going to start a company making electric supercars."
"They'll never work and nobody will buy them. You'll go bankrupt soon."
"So, I've got a big list of buyers for a very real electric supercar."
"Your gearbox problem and price estimate issues will break you. You'll go bankrupt soon."
"So, we've resolved the pricing and gearboxes, and the cars are being delivered to owners"
"Yeah, you're making them at a tiny rate, you'll never scaleup You'll go bankrupt soon."
"So, we scaled up production, and now we're going to make a super long range, even cheaper, luxury car"
"Hahaha, no, that's never going to happen. You'll go bankrupt soon."
"So, we're making the car with basically the specs and pricing we announced."
"Yeah, in tiny numbers. You'll never scale up, and you'll go bankrupt soon."
"So we've scaled up model S production and it's getting great owner satisfaction. We're going to make a crossover now, and then a $30k EV in huge numbers"
"The crossover will be a failure, and those numbers are laughable. You'll never get interest nor raise capital for that. You'll go bankrupt soon."
"So, the crossover is getting great reviews too, we've raised capital to start production of our factories...."

Meanwhile, on the other side:

"Hey, I'm going to start a company to launch payloads into orbit!"
"Har har, this isn't going to last long, you're going to be the next Roton. You'll go bankrupt soon."
"Hey, we've actually got a built and are starting to launch it."
"Yeah, but it's unreliable as heck, and too small to compete for the high dollar contracts. You'll go bankrupt soon."
"Hey, we got the bugs worked out of our rocket, and we're starting work on a vastly larger rocket."
"Har har, like that's ever going to happen. It'll never work, and you'll go bankrupt soon."
"Hey, so we built and are launching our vastly larger rocket..."
"Nobody's going to trust that thing, you'll never be able to compete, you'll go bankrupt soon."
"Hey, we're launching payload after payload, and we're going to start landing and recovering our rockets."
"You're going to land first stages, something even NASA hasn't done? Hahaha, good luck, You'll go bankrupt soon!"
"Hey, so we're pretty consistently landing and recovering rockets now..."

-------

If you want know why people tend to listen to Musk rather than his constant chorus of naysayers, it's because the naysayers have such an unbelievably bad track record with their naysaying. Come on, at least be like a stopped clock and be right once every so often.

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