However... the Tesla vehicles already take advantage of "becoming a generator" as that is part of the "regenerative braking system" used in the vehicle. That ability to "generate electricity" not only doesn't damage the battery, but it helps to recharge the system as well and is an intended behavior... at least if you are going downhill with a tailwind.
I've seen several electric vehicles that have a gasoline-powered "pusher" trailer that provides "emergency power" for long haul trips instead of looking for an outlet for the car. It isn't even that new of an idea for that matter.
Regardless, because of the simplicity of the drive train and that the engine is not an internal combustion engine, calling a dead Roadster "a brick" is going over the top even if you can't disengage the engine from the transmission. Yes, there is a transmission in a Roadster, and there was even going to be a "clutch", but that feature was removed due to the torque issues and other problems from the supplier that was originally going to provide the transmission (something that nearly killed the Roadster when it went into production).
The Roadster is a rear wheel drive vehicle, so I don't think the front wheels are connected to anything other than the steering mechanism. In that regard, it is more like a conventional automobile too. In other words, towing the car is just like towing any other vehicle when you don't have the keys to unlock the transmission from the drive train.
Hydrazine is typically only used for maneuvers and thrusting in space, due to its wide range of temperature stability and the fact that it is hypergolic (ignites itself). LOX and Liquid Hydrogen boil off in a real hurry so it must be used right away (usually not a problem for a rocket's 2nd or 3rd stage). In other words, that fuel isn't being used until you have cleared the atmosphere completely and thus isn't a concern other than "polluting" the solar wind (as if that was even possible).
Some early rockets did used Hydrazine as the primary fuel for atmospheric flight, but I'm not aware of any current vehicles. I might be mistaken on that notion however. ESA might be still using it for at least part of what they are using for their launches on the primary stages.
Masten had technology which was able to accomplish the general goals of the competition, so if they weren't going to even be close there wouldn't have been any controversy at all. My impression was that Armadillo sort of thought going in that they were going to win the 1st place prize for the 2nd tier competition. They even made an attempt a year earlier without much success.
Regardless, in the long run both companies ended up in a pretty good position and I don't think Armadillo Aerospace is thought of any less of a company. Besides, I think Armadillo is doing just fine financially as a company. John Carmack has already talked about how he has put the last bit of capital that he expects to invest into the company until it is doing much bigger things with mature technology. In other words, it is already a profit making business.
I would imagine that making carbon nanotubes of sufficent length...
You do realize that "sufficient length" is on the order of a millimeter, don't you? (And might be much smaller.)
That depends.... on if that will get the job done or if those fibers need to be made longer. Theoretical science and actual engineering can sometimes be quite a bit different. In theory the mere millimeter fibers might get the job done, but until it has actually been tried there will be no real confirmation of theory.
Sort of like how Iridium is regularly being picked over by one company and another. The basic idea is impressive and pushed technology, but the original investors long ago lost every dime they put into the company in the first place. It may be operated by a successful company at the moment, but as an investment strategy it ended up being a total failure.
You wouldn't even notice that lateral force at all, particularly if it took a week to go up. You might get a marble to roll across the floor like a somewhat uneven floor in a poorly constructed house or office, but unless you were actively looking for that force you wouldn't even notice it. Besides, the vehicle would likely be built to orient that force in a downward direction as well.
Here is a thought: If multiple space elevators were in operation around the Earth, would that pretty much end LEO spaceflight altogether?
I'm being serious here too. Yes, you can maneuver to avoid those elevators, but pretty much everything at an altitude less than GEO would need to be halted, and even for aviation there would need to be some pretty strong controlled air space corridors put into place that would in theory extend to GEO.
If anything, this is one reason why I think a space elevator is more than a century away: Just cleaning the junk out of LEO alone is going to take a couple centuries, even with an organized international effort to get that accomplished and cheap access to LEO for cleanup technologies.
I haven't been a huge fan of solid launchers in the first place (especially Ammonium Perchlorate rockets), but this is something I wasn't aware of. For something like an ICBM, the environmental damage from its launch compared to its intended purpose sort of dwarfs the environmental impact (aka an atmospheric nuclear detonation vs. the exhaust plume), but for "routine" launches into orbit this is a big deal.
Cost is my biggest complaint about solid rockets, as they are surprisingly more expensive than efficiently built liquid rockets. The main reason for their use at the moment is to subsidize the maintenance of the ICBM fleets... something I wish was more widely acknowledged.
I'm curious what Kerosene (rocket-grade stuff like RP-1) with LOX does instead. I have a very hard time believing that Liquid Hyrdrogen/LOX rockets do much damage to the stratosphere, other than introducing some very high altitude clouds where water vapor at that altitude might be considered a "greenhouse gas".
I thought the win by Masten for the 2nd tier prize of the Northrup-Grumman Lunar Lander Challenge was completely legitimate. The "shenanigans" was simply following the rules, and that they won the "tie breaker" over Armadillo Aerospace. Yes, John Carmack wasn't too happy about the way they lost, but let's get real about the issues involved.
BTW, while Armadillo Aerospace (not Masten) was one of the original X-Prize teams, the Lunar Landing Challenge was not technically one of the "X-Prizes".. even though Peter Diamandis and the X-Prize Foundation were requested to act as the judges to determine who was the legitimate "winner" of the contest rules might be, it was more legitimately a part of NASA's Centennial Prizes (or Centennial Challenges) series of competitions and the seed money came from the U.S. Federal Government as a NASA appropriation. I know it is splitting hairs, but it is disingenuous for the X-Prize Foundation to be claiming this as one of their own projects even though apparently they have.
The impressive thing is that Armadillo Aerrospace wasn't the only company involved in the "competition". BTW, I was also impressed with Unreasonable Rocket, who has continued to do other things since the competition as well. Perhaps the best thing that happened is that Masten got some important seed money by winning 1st place for the level 2 competition, and they've spent that money in a very wise manner while Armadillo Aerospace has been well funded because of John Carmack. Both companies (AA and MSS) have also worked with NASA on various projects in an attempt to leverage the expertise learned from the Lunar Landing Challenge, noting that the challenges they have in terms of control systems working here on the Earth are actually going to be tougher due to the high gravity than what they are going to need on the Moon or asteroids.
The point of the challenge (especially Level 2) is that the delta v needed to win the prize was the same as what would be needed to launch from the surface of the Moon, go to a lunar rendezvous orbit (like what the Apollo project did for their Lunar Orbit Rendezvous scheme), and then safely land back on the surface of the Moon (or the other way around). In theory, both companies now have the technological capability of being able to land and retrieve rock samples from the surface of the Moon with their vehicles... if only you could get those landers to Lunar orbit in the first place.
Are any of the Grumman engineers still around to build a follow-up module if we ever want to go back? Most of them are either pushing up daisies or collecting retirement benefits... think about it.
I'm glad that *somebody* is working on these skills in some way to make sure that the capability is even possible.
I'm also glad that computing power has advanced beyond discrete transistors and 7400 logic gate chips that are the size of your thumb, because that is what the original Apollo Guidance Computer was built out of.
If anything, an ICBM needs to travel as fast as it can, and have a huge acceleration for the purpose of reducing reaction time for incoming warheads. That goes completely against the design philosophy of launches intended for spaceflight, much less a rocket-powered lander. A typical nuclear warhead is really quite sturdy and can handle high acceleration forces (100-200 m/s^2 are common, sometimes up to as high as 400 depending on the missile). A typical satellite payload package usually is only built to handle forces up to about 50 m/s^2 (about 5 "G's") and some launchers try to drop that acceleration even further.
The point being that I agree with you (and not the grandparent) in terms of any danger in terms of weaponizing these kind of rockets. There may be some common components for commercial spaceflight launchers and what you can find for military missiles, but there are enough major differences that they are not interchangeable. This is especially true for "modern" rocket designs, where there is a clear separation of the designs because they have different objectives in terms of flight profile and performance characteristics.
If commercial spaceflight pushes the boundaries even more, this differences is something I think is going to be even more pronounced as rockets are being designed not for high performance but rather to simply be cheap. This rocket made by Masten is definitely pushing the envelope of being cheap. The budget for this project is something equivalent to a "petty cash fund" that is so low it doesn't need any specific appropriation legislation to make happen. I don't know the exact amount Masten is getting from NASA, but it is in the mere thousands of dollars, certainly less than a million. Normally NASA can't even do a paper study for less than a million dollars, much less pay for a working rocket.
You can trace mined coins to specific IP addresses if you are careful with how you listen to the packets and try to find out which computer gave you the packet first. If you had several computers tracking this information, it would be possible to identify down to a small number of users who actually mined some Bitcoins, and from that if any Bitcoins were co-mingled with those mined coins to be able to further identify what other addresses might be used by that person who also is mining coins.
Still, attempting to do that is a real technical challenge and you would need the resources of something like the U.S. federal government to pull that off, plus a whole bunch of data mining and active participation in the Bitcoin network... and it still gives wiggle room for plausible deniability on the surface. If there was a particular set of transactions that such data mining was looking for, you can still be tracked.
On the other hand, if you were very paranoid about such things you could set up manual connections for routing Bitcoin data to only trusted nodes (by your own definition... not some random list in other words), and hopefully even they are being just as paranoid about random connections "to the outside world".
On the other hand, every single transaction for the entire history of Bitcoin from the day the original root block was created is clearly available for anybody in the world to look at. You can identify not just the amounts but to whom it was paid, "processing fees" associated with those transactions, and a detailed "chain of custody" for every Bitcoin.
There are ways to anonymously transfer Bitcoins, but in and of itself Bitcoin is not nearly so anonymous as some people make the claim it is. The tough part is linking a particular Bitcoin address with an IP address.... which is a much harder proposition to make. Even that isn't impossible, but it can be much harder. It is much, much easier to perform that step if you happen to operate one of the major Bitcoin exchanges, as you can link the BTC information with user registration information and connection data to the exchange website.
The other saving grace is that most Bitcoin transactions are of such petty values that it would never trigger a reporting event in the first place even if it was a normal monetary transaction.
The algorithm has an adjustment factor based upon how long it took to generate the previous number of blocks (I'd have to dig into the algorithm to find the exact number). If one day a huge amount of CPU power is suddenly dumped into Bitcoin in an attempt to hoard the coins, the adjustment factor increases by a factor that compensates for the increase in computing power.
Sure, over a short period of time you will generate a whole bunch of new blocks as the system adapts to take in the new amount of computing power, but eventually the algorithm adapts to the sudden influx of new blocks solved and makes it harder to create the next block. So with your example of 300 new computers jumping into the system, those computers will at first have the ability to create blocks with the old difficulty level... until they start churning out new blocks and grabbing the available coins.
The opposite happens too, where a whole bunch of computers leave the network (people give up trying to find bitcoins) and then it simply takes longer between blocks. When that happens, the algorithms reduces difficulty after a few blocks are "discovered" and then it eventually becomes easier to find the next block.
There is a lag in how quickly the algorithm takes to adjust, and note that random events will also make some blocks naturally appear sooner simply because of random chance.
The best way to describe the search algorithm is more like playing something like the multi-state lotto, where your computer attempts to find the "winning" numbers, and when you find the correct numbers you have "won" the lotto for that 10 minute time period (for a whopping 50 Bitcoins). The difficulty adjustment factor is more like having to pick seven numbers instead of six, or perhaps it goes up to eight or nine numbers, and when it becomes too hard because nobody is winning the string of numbers you need to pick goes down. This isn't a perfect analogy, but if you are familiar with lotteries it might make a little more sense.
It isn't that hard to implement "fixed decimal point" mathematical algorithms. It can be done on any computer which has integer opcodes... which is just about every computer ever built since ENIAC. The rounding you are referring to is due to floating point numbers where the numbers are rounded when they are put into the data format in the first place.
Making a "fixed point data type" in C++, C#, Java, or other more modern languages is simply creating that data type in the first place, and most of those languages have operator overloading for those data types that make the task trivial once you've implemented the type. I'm sure simply looking around can find find that already written as a library, but any programmer worthy of the title should be able to create these data types from scratch in those languages.
C and its derivatives also move strings around very efficiently, but I'll admit the programmer interface into accessing those functions is clunky and obfuscated, while COBOL does it as a designed behavior of the language.
As for static variables, the problems that come from the dynamic variables has more to do with how programmers using those languages have been taught to use them, where dynamic variables are considered ordinary and the developers insist upon pointer references in libraries and common interfaces. Again, it doesn't have to be done that way, but the API standards push it to be that way. COBOL comes from an earlier time when such techniques simply weren't taught.
Traditionally in Mainframes they had larger bus sizes and register sizes, which for fixed point calculations is critical. With most microcomputers having 64 bit registers as a common practice and even some low-end game consoles having 128 or even 256 bit registers, the real strengths of mainframes in terms of computing power is almost lost. About the only benefit to mainframes any more is strictly the uptime and circuit redundancy for hot-swapping components. For computing tasks that take hours or days to complete, that can be very important.
A hinged door, at least an ordinary hinged door, doesn't have nearly so many moving parts and therefore is much less likely to break down. For new vehicles, I realize that isn't nearly so big of a deal, but in time sliding doors can be a real pain to work with, particular with older vehicles. They just need a whole lot more attention.
One problem that you've glossed over here on the sliding door, however, is that the door can only be as long as the side of the vehicle, or you have to invent a really exotic system to physically carry the sliding door. Generally there is a track on the bottom of the vehicle that the door slides upon, and that must be at least as long as the door itself. That track BTW is also one of the sources of problems, if it gets gummed up with "stuff". That is something you don't find with any other door system.
One nice thing about the gull-wing doors (or more like the Model X) is that there isn't any real limit on the length of the door. They can be as large or as small as they need to be with the design of the vehicle being used. There is a support mechanism that must be put into place to hold the door up while it is open (so it doesn't go slamming onto your hand or fingers), and that is also where you are most likely to see some sort of mechanical failure as well.
An ordinary hinged door doesn't have those problems.
In terms of the plug, I don't see the difference between the power consumption of a heavy electric appliance like a kitchen range, electric clothes dryer, and an electric automobile. Yes, the power consumption is a bit higher, but not significantly so. I think you could build a "fool proof" plug and have some resemblance of safety... although your point is very valid that the amount of energy going through that cable is huge and needs to be treated with respect. You certainly don't want to have some firefighter using the "jaws of life" and cutting through that cable in some kind of vehicle rescue attempt. It certainly isn't like trying to install a car radio... which is very low voltage and comparatively low amperage.
In terms of the salt water spray and other things getting onto the battery and cable, I'd agree that is a big deal too. Imagining somebody pulling into a Chicago battery swap station covered in snow, mud, and salt in the Winter and then somebody reaching through a puddle of that muck to unplug the battery pack..... I shudder at the thought.
Then again, people have been known to die from dispensing gasoline. Usually doing very stupid things (like some woman with nylon stockings getting in and out of her car building up a static charge and then grounding her automobile to the gas pump right at the nozzle) or simply being careless.
It isn't that the issue isn't raised, the problem is that the size of the battery pack is so huge that you need some kind of pallet truck to move the thing around and a specialized storage location to be able to recharge these battery packs.
From what I understand about the Model S, the idea that eventually such a service might show up was considered, where battery packs could be removed with just a few bolts being taken off and a single connector cable with a "plug" that could easily be disconnected and reconnected. I don't know if the process has been seriously explored in terms of somebody coming up with a business plan and actually setting up shop to perform this task, noting that at the moment each battery pack that is being produced can only be used for a single automobile manufacturer. If these battery packs could become somewhat standardized, perhaps this idea might get a little more merit.
This certainly isn't a new idea, and yes, it is being considered. Perhaps you want to start up the business yourself?
Keep in mind that when electric vehicles like the Roadster start to lose their charge, they merely slow down. Instead of driving on the freeway, you need to take the surface streets to get home. Not quite "pushing it into the garage", but it can take longer.
The time it takes to recharge the vehicle is mainly dependent upon the charger station you are using. Most home units have a 220 volt main power tap, but the 110 volt charger (easier to find and install) takes longer because it has lower amperage as well. If you want something to recharge faster, all you "need" to do is find some way to get that energy into the battery faster. I suppose you could hook a direct high voltage power line into your battery charger from a 1 MW power plant and recharge your battery in under an hour. Do you want to be doing that power source connection your self or hiring a minimum-wage convenience store attendant to perform that task for you?
I think the difference is Martin Eberhard. While Elon Musk certainly gave some input into the design of the Roadster, it was Eberhard's design almost the whole way (for good and ill). Musk insisted upon a design that "wouldn't suck", but Eberhard is the one who gave it class and made it look real cool.
If you notice a difference between the Roadster and the Model S & X, he would be the missing element. I'm not saying that Tesla needs to hire Eberhard back, but that he was a major influence to the sexy look that became the Roadster.
Not really, but this is an often repeated rumor. The Lotus Elise and the Roadster chassis were produced at the same manufacturing plant with even the same production line, and they were about the same size in terms of rough dimensions, but the designs were definitely different and did require different tooling when there was a switch between the two vehicles.
The biggest difference is that the Tesla Roadster had a more American feel with a slightly wider chassis, lower door frame to the ground, and a center console more reflecting American tastes (as opposed to the Lotus reflection of British sensibilities). There were also separate supply chains for the two chassis as well, coming from different sub-contractors. About the only real feature that I think was shared between the two vehicles were the headlights. There were a couple other parts that came from Lotus, but they were minor.
In other words, the "customization" was far more than just minimal, and did reflect completely different engineering teams being involved for the two vehicles. The Tesla blogs go into more detail with this issue, but I don't have the patience today to be bothering to look up the exact reference in that heap dump at the moment.
I hate to say it because I really admire the guy too, but canning Martin Eberhardt was perhaps the single most intelligent thing that Elon Musk ever did.
I understand why the original Tesla founder did the thing that he did, but he also showed that he was out of his element in terms of operating a major automotive manufacturing company. A brilliant designer and certainly somebody who helped bring Tesla up to where it is today in terms of doing a fantastic job of going from start-up and through the prototyping stages of the Roadster, but closing the deal was very hard.
What was the nearly fatal blow was the transmission of the Roadster. Eberhardt chose to outsource nearly all of the parts and production of the Roadster in the initial proposal, and this included the transmission system going from the motor to the wheels. The problem is that an electric motor of the kind that Tesla was using had far more torque being applied than is typical for that size of vehicle using an internal combustion engine. When all was said and done, the transmission simply didn't work and Tesla was faced with trying to find a replacement that would even just "make do" much less have the performance they were expecting.
Originally it was supposed to be a two speed transmission (High and Low gear ratios) with the idea that you get higher torque at the low gear, but use the high gear for highway cruising. The transmission to get that accomplished simply wouldn't last that long (I heard reports of just a few hundred or a thousand miles between transmission replacements on the engineering prototypes) and such a situation simply was not going to be useful for the final production version. The final transmission couldn't even be shipped in time to be put into the first production vehicles coming from England, so it had to be installed when the first production cars arrived in California. Eventually that "temporary" assembly facility ended up becoming much more permanent and about all that Lotus ended up building were the "gliders" where the final assembly took place in California. That was not the original intention, but that is how it ended up.
One other huge problem with the early production versions was a significant problem with the battery controller. Essentially it had a bunch of bugs in the firmware that needed to be worked out, and it took time to get it working correctly so it wasn't constantly requiring a charge or discharging even when the Roadster was idle. Basically the early Roadsters sitting in a parking lot would discharge its battery rather quickly. This problem was eventually resolved, but it was an embarrassment and sort of glossed over by the Tesla PR team. Because all of the Roadsters with the problem were still under warranty, when the vehicles were brought in for "routine service", the firmware and in some cases the entire battery pack was replaced,.
There were other problems as well, and it was that transition from the engineering prototype to a real production vehicle that was the tough stretch. Elon Musk was also stretched real thin in regards to SpaceX, which was also having problems in terms of being able to actually get into space and really digging into cash reserves. That Elon Musk weathered that storm is all that more amazing, and went through a divorce all at the same time.
Musk also tried to move Tesla Motors to the Los Angeles area (with a facility in Long Beach that almost was built) in part so he wouldn't have to commute between the two companies. Then the NUMMI plant became available with a cash infusion by Toyota that made Tesla what it is today. While Tesla certainly is still very much entrepreneurial in their attitude towards car making, they are not nearly on that razor edge they were back at the introduction of the Roadster.
What government subsidy? Are you talking the electric vehicle promotion rebates and tax incentives?
Those are not specific to Tesla Motors but to all electric vehicles of all manufacturers. While you might argue such tax incentives are stupid and foolish, it is the electric vehicle concept that is the problem or "solution" here and not just Tesla.
If you are talking the George W. Bush-era guaranteed loan program that Tesla applied for funding under to build the Model S.... I suppose that is somewhat justified. Still, that was a loan that had to be paid back and wasn't really a subsidy. In fact, the loan program was originally designed by lobbyists for General Motors and Toyota, but it turns out that Tesla Motors just happened to fit all of the qualifications for the same program and was able to get in on the same deal.... just as any other electric car manufacturer could have done at the same time.
I won't even get into the "bigger lifetime carbon footprint", as I don't think you can even remotely justify that statement. That is sheer fabrication and false. The transportation, refining, and dispensing of gasoline has a pretty huge carbon footprint too, and is far more energy inefficient and produces far more carbon than distributing a similar amount of electricity where you get economies of scale and much more efficient energy production for a given amount of energy consumed in a vehicle. Electricity is also fuel agnostic and can be created with whatever fuel happens to be cheapest at the time. There also is no fear of running out of electricity due to a war in the Middle East or a boycott like what happened in the 1970's.
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However... the Tesla vehicles already take advantage of "becoming a generator" as that is part of the "regenerative braking system" used in the vehicle. That ability to "generate electricity" not only doesn't damage the battery, but it helps to recharge the system as well and is an intended behavior... at least if you are going downhill with a tailwind.
I've seen several electric vehicles that have a gasoline-powered "pusher" trailer that provides "emergency power" for long haul trips instead of looking for an outlet for the car. It isn't even that new of an idea for that matter.
Regardless, because of the simplicity of the drive train and that the engine is not an internal combustion engine, calling a dead Roadster "a brick" is going over the top even if you can't disengage the engine from the transmission. Yes, there is a transmission in a Roadster, and there was even going to be a "clutch", but that feature was removed due to the torque issues and other problems from the supplier that was originally going to provide the transmission (something that nearly killed the Roadster when it went into production).
The Roadster is a rear wheel drive vehicle, so I don't think the front wheels are connected to anything other than the steering mechanism. In that regard, it is more like a conventional automobile too. In other words, towing the car is just like towing any other vehicle when you don't have the keys to unlock the transmission from the drive train.
Hydrazine is typically only used for maneuvers and thrusting in space, due to its wide range of temperature stability and the fact that it is hypergolic (ignites itself). LOX and Liquid Hydrogen boil off in a real hurry so it must be used right away (usually not a problem for a rocket's 2nd or 3rd stage). In other words, that fuel isn't being used until you have cleared the atmosphere completely and thus isn't a concern other than "polluting" the solar wind (as if that was even possible).
Some early rockets did used Hydrazine as the primary fuel for atmospheric flight, but I'm not aware of any current vehicles. I might be mistaken on that notion however. ESA might be still using it for at least part of what they are using for their launches on the primary stages.
It sounds like being a sore loser.
Masten had technology which was able to accomplish the general goals of the competition, so if they weren't going to even be close there wouldn't have been any controversy at all. My impression was that Armadillo sort of thought going in that they were going to win the 1st place prize for the 2nd tier competition. They even made an attempt a year earlier without much success.
Regardless, in the long run both companies ended up in a pretty good position and I don't think Armadillo Aerospace is thought of any less of a company. Besides, I think Armadillo is doing just fine financially as a company. John Carmack has already talked about how he has put the last bit of capital that he expects to invest into the company until it is doing much bigger things with mature technology. In other words, it is already a profit making business.
You do realize that "sufficient length" is on the order of a millimeter, don't you? (And might be much smaller.)
That depends.... on if that will get the job done or if those fibers need to be made longer. Theoretical science and actual engineering can sometimes be quite a bit different. In theory the mere millimeter fibers might get the job done, but until it has actually been tried there will be no real confirmation of theory.
Sort of like how Iridium is regularly being picked over by one company and another. The basic idea is impressive and pushed technology, but the original investors long ago lost every dime they put into the company in the first place. It may be operated by a successful company at the moment, but as an investment strategy it ended up being a total failure.
You wouldn't even notice that lateral force at all, particularly if it took a week to go up. You might get a marble to roll across the floor like a somewhat uneven floor in a poorly constructed house or office, but unless you were actively looking for that force you wouldn't even notice it. Besides, the vehicle would likely be built to orient that force in a downward direction as well.
So there really is a screen door on a submarine?
Here is a thought: If multiple space elevators were in operation around the Earth, would that pretty much end LEO spaceflight altogether?
I'm being serious here too. Yes, you can maneuver to avoid those elevators, but pretty much everything at an altitude less than GEO would need to be halted, and even for aviation there would need to be some pretty strong controlled air space corridors put into place that would in theory extend to GEO.
If anything, this is one reason why I think a space elevator is more than a century away: Just cleaning the junk out of LEO alone is going to take a couple centuries, even with an organized international effort to get that accomplished and cheap access to LEO for cleanup technologies.
I haven't been a huge fan of solid launchers in the first place (especially Ammonium Perchlorate rockets), but this is something I wasn't aware of. For something like an ICBM, the environmental damage from its launch compared to its intended purpose sort of dwarfs the environmental impact (aka an atmospheric nuclear detonation vs. the exhaust plume), but for "routine" launches into orbit this is a big deal.
Cost is my biggest complaint about solid rockets, as they are surprisingly more expensive than efficiently built liquid rockets. The main reason for their use at the moment is to subsidize the maintenance of the ICBM fleets... something I wish was more widely acknowledged.
I'm curious what Kerosene (rocket-grade stuff like RP-1) with LOX does instead. I have a very hard time believing that Liquid Hyrdrogen/LOX rockets do much damage to the stratosphere, other than introducing some very high altitude clouds where water vapor at that altitude might be considered a "greenhouse gas".
I thought the win by Masten for the 2nd tier prize of the Northrup-Grumman Lunar Lander Challenge was completely legitimate. The "shenanigans" was simply following the rules, and that they won the "tie breaker" over Armadillo Aerospace. Yes, John Carmack wasn't too happy about the way they lost, but let's get real about the issues involved.
BTW, while Armadillo Aerospace (not Masten) was one of the original X-Prize teams, the Lunar Landing Challenge was not technically one of the "X-Prizes".. even though Peter Diamandis and the X-Prize Foundation were requested to act as the judges to determine who was the legitimate "winner" of the contest rules might be, it was more legitimately a part of NASA's Centennial Prizes (or Centennial Challenges) series of competitions and the seed money came from the U.S. Federal Government as a NASA appropriation. I know it is splitting hairs, but it is disingenuous for the X-Prize Foundation to be claiming this as one of their own projects even though apparently they have.
The impressive thing is that Armadillo Aerrospace wasn't the only company involved in the "competition". BTW, I was also impressed with Unreasonable Rocket, who has continued to do other things since the competition as well. Perhaps the best thing that happened is that Masten got some important seed money by winning 1st place for the level 2 competition, and they've spent that money in a very wise manner while Armadillo Aerospace has been well funded because of John Carmack. Both companies (AA and MSS) have also worked with NASA on various projects in an attempt to leverage the expertise learned from the Lunar Landing Challenge, noting that the challenges they have in terms of control systems working here on the Earth are actually going to be tougher due to the high gravity than what they are going to need on the Moon or asteroids.
The point of the challenge (especially Level 2) is that the delta v needed to win the prize was the same as what would be needed to launch from the surface of the Moon, go to a lunar rendezvous orbit (like what the Apollo project did for their Lunar Orbit Rendezvous scheme), and then safely land back on the surface of the Moon (or the other way around). In theory, both companies now have the technological capability of being able to land and retrieve rock samples from the surface of the Moon with their vehicles... if only you could get those landers to Lunar orbit in the first place.
Are any of the Grumman engineers still around to build a follow-up module if we ever want to go back? Most of them are either pushing up daisies or collecting retirement benefits... think about it.
I'm glad that *somebody* is working on these skills in some way to make sure that the capability is even possible.
I'm also glad that computing power has advanced beyond discrete transistors and 7400 logic gate chips that are the size of your thumb, because that is what the original Apollo Guidance Computer was built out of.
If anything, an ICBM needs to travel as fast as it can, and have a huge acceleration for the purpose of reducing reaction time for incoming warheads. That goes completely against the design philosophy of launches intended for spaceflight, much less a rocket-powered lander. A typical nuclear warhead is really quite sturdy and can handle high acceleration forces (100-200 m/s^2 are common, sometimes up to as high as 400 depending on the missile). A typical satellite payload package usually is only built to handle forces up to about 50 m/s^2 (about 5 "G's") and some launchers try to drop that acceleration even further.
The point being that I agree with you (and not the grandparent) in terms of any danger in terms of weaponizing these kind of rockets. There may be some common components for commercial spaceflight launchers and what you can find for military missiles, but there are enough major differences that they are not interchangeable. This is especially true for "modern" rocket designs, where there is a clear separation of the designs because they have different objectives in terms of flight profile and performance characteristics.
If commercial spaceflight pushes the boundaries even more, this differences is something I think is going to be even more pronounced as rockets are being designed not for high performance but rather to simply be cheap. This rocket made by Masten is definitely pushing the envelope of being cheap. The budget for this project is something equivalent to a "petty cash fund" that is so low it doesn't need any specific appropriation legislation to make happen. I don't know the exact amount Masten is getting from NASA, but it is in the mere thousands of dollars, certainly less than a million. Normally NASA can't even do a paper study for less than a million dollars, much less pay for a working rocket.
You can trace mined coins to specific IP addresses if you are careful with how you listen to the packets and try to find out which computer gave you the packet first. If you had several computers tracking this information, it would be possible to identify down to a small number of users who actually mined some Bitcoins, and from that if any Bitcoins were co-mingled with those mined coins to be able to further identify what other addresses might be used by that person who also is mining coins.
Still, attempting to do that is a real technical challenge and you would need the resources of something like the U.S. federal government to pull that off, plus a whole bunch of data mining and active participation in the Bitcoin network... and it still gives wiggle room for plausible deniability on the surface. If there was a particular set of transactions that such data mining was looking for, you can still be tracked.
On the other hand, if you were very paranoid about such things you could set up manual connections for routing Bitcoin data to only trusted nodes (by your own definition... not some random list in other words), and hopefully even they are being just as paranoid about random connections "to the outside world".
You can use coins until RFID tags get put into them. Seriously, even cash transactions can be traced.
BTW, in terms of serial number trackers for U.S. currency, this website does a pretty good job:
http://www.wheresgeorge.com/
This isn't even paranoia, and you might be surprised at how much of the cash in your wallet is being tracked.
On the other hand, every single transaction for the entire history of Bitcoin from the day the original root block was created is clearly available for anybody in the world to look at. You can identify not just the amounts but to whom it was paid, "processing fees" associated with those transactions, and a detailed "chain of custody" for every Bitcoin.
There are ways to anonymously transfer Bitcoins, but in and of itself Bitcoin is not nearly so anonymous as some people make the claim it is. The tough part is linking a particular Bitcoin address with an IP address.... which is a much harder proposition to make. Even that isn't impossible, but it can be much harder. It is much, much easier to perform that step if you happen to operate one of the major Bitcoin exchanges, as you can link the BTC information with user registration information and connection data to the exchange website.
The other saving grace is that most Bitcoin transactions are of such petty values that it would never trigger a reporting event in the first place even if it was a normal monetary transaction.
The algorithm has an adjustment factor based upon how long it took to generate the previous number of blocks (I'd have to dig into the algorithm to find the exact number). If one day a huge amount of CPU power is suddenly dumped into Bitcoin in an attempt to hoard the coins, the adjustment factor increases by a factor that compensates for the increase in computing power.
Sure, over a short period of time you will generate a whole bunch of new blocks as the system adapts to take in the new amount of computing power, but eventually the algorithm adapts to the sudden influx of new blocks solved and makes it harder to create the next block. So with your example of 300 new computers jumping into the system, those computers will at first have the ability to create blocks with the old difficulty level... until they start churning out new blocks and grabbing the available coins.
The opposite happens too, where a whole bunch of computers leave the network (people give up trying to find bitcoins) and then it simply takes longer between blocks. When that happens, the algorithms reduces difficulty after a few blocks are "discovered" and then it eventually becomes easier to find the next block.
There is a lag in how quickly the algorithm takes to adjust, and note that random events will also make some blocks naturally appear sooner simply because of random chance.
The best way to describe the search algorithm is more like playing something like the multi-state lotto, where your computer attempts to find the "winning" numbers, and when you find the correct numbers you have "won" the lotto for that 10 minute time period (for a whopping 50 Bitcoins). The difficulty adjustment factor is more like having to pick seven numbers instead of six, or perhaps it goes up to eight or nine numbers, and when it becomes too hard because nobody is winning the string of numbers you need to pick goes down. This isn't a perfect analogy, but if you are familiar with lotteries it might make a little more sense.
It isn't that hard to implement "fixed decimal point" mathematical algorithms. It can be done on any computer which has integer opcodes... which is just about every computer ever built since ENIAC. The rounding you are referring to is due to floating point numbers where the numbers are rounded when they are put into the data format in the first place.
Making a "fixed point data type" in C++, C#, Java, or other more modern languages is simply creating that data type in the first place, and most of those languages have operator overloading for those data types that make the task trivial once you've implemented the type. I'm sure simply looking around can find find that already written as a library, but any programmer worthy of the title should be able to create these data types from scratch in those languages.
C and its derivatives also move strings around very efficiently, but I'll admit the programmer interface into accessing those functions is clunky and obfuscated, while COBOL does it as a designed behavior of the language.
As for static variables, the problems that come from the dynamic variables has more to do with how programmers using those languages have been taught to use them, where dynamic variables are considered ordinary and the developers insist upon pointer references in libraries and common interfaces. Again, it doesn't have to be done that way, but the API standards push it to be that way. COBOL comes from an earlier time when such techniques simply weren't taught.
Traditionally in Mainframes they had larger bus sizes and register sizes, which for fixed point calculations is critical. With most microcomputers having 64 bit registers as a common practice and even some low-end game consoles having 128 or even 256 bit registers, the real strengths of mainframes in terms of computing power is almost lost. About the only benefit to mainframes any more is strictly the uptime and circuit redundancy for hot-swapping components. For computing tasks that take hours or days to complete, that can be very important.
A hinged door, at least an ordinary hinged door, doesn't have nearly so many moving parts and therefore is much less likely to break down. For new vehicles, I realize that isn't nearly so big of a deal, but in time sliding doors can be a real pain to work with, particular with older vehicles. They just need a whole lot more attention.
One problem that you've glossed over here on the sliding door, however, is that the door can only be as long as the side of the vehicle, or you have to invent a really exotic system to physically carry the sliding door. Generally there is a track on the bottom of the vehicle that the door slides upon, and that must be at least as long as the door itself. That track BTW is also one of the sources of problems, if it gets gummed up with "stuff". That is something you don't find with any other door system.
One nice thing about the gull-wing doors (or more like the Model X) is that there isn't any real limit on the length of the door. They can be as large or as small as they need to be with the design of the vehicle being used. There is a support mechanism that must be put into place to hold the door up while it is open (so it doesn't go slamming onto your hand or fingers), and that is also where you are most likely to see some sort of mechanical failure as well.
An ordinary hinged door doesn't have those problems.
In terms of the plug, I don't see the difference between the power consumption of a heavy electric appliance like a kitchen range, electric clothes dryer, and an electric automobile. Yes, the power consumption is a bit higher, but not significantly so. I think you could build a "fool proof" plug and have some resemblance of safety... although your point is very valid that the amount of energy going through that cable is huge and needs to be treated with respect. You certainly don't want to have some firefighter using the "jaws of life" and cutting through that cable in some kind of vehicle rescue attempt. It certainly isn't like trying to install a car radio... which is very low voltage and comparatively low amperage.
In terms of the salt water spray and other things getting onto the battery and cable, I'd agree that is a big deal too. Imagining somebody pulling into a Chicago battery swap station covered in snow, mud, and salt in the Winter and then somebody reaching through a puddle of that muck to unplug the battery pack..... I shudder at the thought.
Then again, people have been known to die from dispensing gasoline. Usually doing very stupid things (like some woman with nylon stockings getting in and out of her car building up a static charge and then grounding her automobile to the gas pump right at the nozzle) or simply being careless.
It isn't that the issue isn't raised, the problem is that the size of the battery pack is so huge that you need some kind of pallet truck to move the thing around and a specialized storage location to be able to recharge these battery packs.
From what I understand about the Model S, the idea that eventually such a service might show up was considered, where battery packs could be removed with just a few bolts being taken off and a single connector cable with a "plug" that could easily be disconnected and reconnected. I don't know if the process has been seriously explored in terms of somebody coming up with a business plan and actually setting up shop to perform this task, noting that at the moment each battery pack that is being produced can only be used for a single automobile manufacturer. If these battery packs could become somewhat standardized, perhaps this idea might get a little more merit.
This certainly isn't a new idea, and yes, it is being considered. Perhaps you want to start up the business yourself?
Keep in mind that when electric vehicles like the Roadster start to lose their charge, they merely slow down. Instead of driving on the freeway, you need to take the surface streets to get home. Not quite "pushing it into the garage", but it can take longer.
The time it takes to recharge the vehicle is mainly dependent upon the charger station you are using. Most home units have a 220 volt main power tap, but the 110 volt charger (easier to find and install) takes longer because it has lower amperage as well. If you want something to recharge faster, all you "need" to do is find some way to get that energy into the battery faster. I suppose you could hook a direct high voltage power line into your battery charger from a 1 MW power plant and recharge your battery in under an hour. Do you want to be doing that power source connection your self or hiring a minimum-wage convenience store attendant to perform that task for you?
I think the difference is Martin Eberhard. While Elon Musk certainly gave some input into the design of the Roadster, it was Eberhard's design almost the whole way (for good and ill). Musk insisted upon a design that "wouldn't suck", but Eberhard is the one who gave it class and made it look real cool.
If you notice a difference between the Roadster and the Model S & X, he would be the missing element. I'm not saying that Tesla needs to hire Eberhard back, but that he was a major influence to the sexy look that became the Roadster.
Not really, but this is an often repeated rumor. The Lotus Elise and the Roadster chassis were produced at the same manufacturing plant with even the same production line, and they were about the same size in terms of rough dimensions, but the designs were definitely different and did require different tooling when there was a switch between the two vehicles.
The biggest difference is that the Tesla Roadster had a more American feel with a slightly wider chassis, lower door frame to the ground, and a center console more reflecting American tastes (as opposed to the Lotus reflection of British sensibilities). There were also separate supply chains for the two chassis as well, coming from different sub-contractors. About the only real feature that I think was shared between the two vehicles were the headlights. There were a couple other parts that came from Lotus, but they were minor.
In other words, the "customization" was far more than just minimal, and did reflect completely different engineering teams being involved for the two vehicles. The Tesla blogs go into more detail with this issue, but I don't have the patience today to be bothering to look up the exact reference in that heap dump at the moment.
I hate to say it because I really admire the guy too, but canning Martin Eberhardt was perhaps the single most intelligent thing that Elon Musk ever did.
I understand why the original Tesla founder did the thing that he did, but he also showed that he was out of his element in terms of operating a major automotive manufacturing company. A brilliant designer and certainly somebody who helped bring Tesla up to where it is today in terms of doing a fantastic job of going from start-up and through the prototyping stages of the Roadster, but closing the deal was very hard.
What was the nearly fatal blow was the transmission of the Roadster. Eberhardt chose to outsource nearly all of the parts and production of the Roadster in the initial proposal, and this included the transmission system going from the motor to the wheels. The problem is that an electric motor of the kind that Tesla was using had far more torque being applied than is typical for that size of vehicle using an internal combustion engine. When all was said and done, the transmission simply didn't work and Tesla was faced with trying to find a replacement that would even just "make do" much less have the performance they were expecting.
Originally it was supposed to be a two speed transmission (High and Low gear ratios) with the idea that you get higher torque at the low gear, but use the high gear for highway cruising. The transmission to get that accomplished simply wouldn't last that long (I heard reports of just a few hundred or a thousand miles between transmission replacements on the engineering prototypes) and such a situation simply was not going to be useful for the final production version. The final transmission couldn't even be shipped in time to be put into the first production vehicles coming from England, so it had to be installed when the first production cars arrived in California. Eventually that "temporary" assembly facility ended up becoming much more permanent and about all that Lotus ended up building were the "gliders" where the final assembly took place in California. That was not the original intention, but that is how it ended up.
One other huge problem with the early production versions was a significant problem with the battery controller. Essentially it had a bunch of bugs in the firmware that needed to be worked out, and it took time to get it working correctly so it wasn't constantly requiring a charge or discharging even when the Roadster was idle. Basically the early Roadsters sitting in a parking lot would discharge its battery rather quickly. This problem was eventually resolved, but it was an embarrassment and sort of glossed over by the Tesla PR team. Because all of the Roadsters with the problem were still under warranty, when the vehicles were brought in for "routine service", the firmware and in some cases the entire battery pack was replaced,.
There were other problems as well, and it was that transition from the engineering prototype to a real production vehicle that was the tough stretch. Elon Musk was also stretched real thin in regards to SpaceX, which was also having problems in terms of being able to actually get into space and really digging into cash reserves. That Elon Musk weathered that storm is all that more amazing, and went through a divorce all at the same time.
Musk also tried to move Tesla Motors to the Los Angeles area (with a facility in Long Beach that almost was built) in part so he wouldn't have to commute between the two companies. Then the NUMMI plant became available with a cash infusion by Toyota that made Tesla what it is today. While Tesla certainly is still very much entrepreneurial in their attitude towards car making, they are not nearly on that razor edge they were back at the introduction of the Roadster.
What government subsidy? Are you talking the electric vehicle promotion rebates and tax incentives?
Those are not specific to Tesla Motors but to all electric vehicles of all manufacturers. While you might argue such tax incentives are stupid and foolish, it is the electric vehicle concept that is the problem or "solution" here and not just Tesla.
If you are talking the George W. Bush-era guaranteed loan program that Tesla applied for funding under to build the Model S.... I suppose that is somewhat justified. Still, that was a loan that had to be paid back and wasn't really a subsidy. In fact, the loan program was originally designed by lobbyists for General Motors and Toyota, but it turns out that Tesla Motors just happened to fit all of the qualifications for the same program and was able to get in on the same deal.... just as any other electric car manufacturer could have done at the same time.
I won't even get into the "bigger lifetime carbon footprint", as I don't think you can even remotely justify that statement. That is sheer fabrication and false. The transportation, refining, and dispensing of gasoline has a pretty huge carbon footprint too, and is far more energy inefficient and produces far more carbon than distributing a similar amount of electricity where you get economies of scale and much more efficient energy production for a given amount of energy consumed in a vehicle. Electricity is also fuel agnostic and can be created with whatever fuel happens to be cheapest at the time. There also is no fear of running out of electricity due to a war in the Middle East or a boycott like what happened in the 1970's.