neaanopri

Gas taxes are already an effective road use tax, with infrastructure for collection already in place

Gas taxes are already effectively toll-per-mile, with a bonus incentive to get fuel efficient cars.

If we start seeing enough EV adoption to dent gas tax revenues, that's a win.

UWB deals with multipath by having very short pulses. The direct path is always faster, so the "true" pulse is the one which arrives first.

UWB is for locating, not for data here.

This doesn't mean driving is useless. Cars are generally air conditioned, and have a greater capacity to carry luggage than walking.

...so cars should this be _slower_ than cars, given these benefits

Gotcha, so the ideas of "Shut Up and Calculate" QM about wavefunction collapse for ideal systems aren't incomplete.

Okay, so you're a quantum physicist and you can answer my question!

My understanding of QM is that a quantum's system's state is suddenly and discontinuously changed by a measurement.

My understanding of this article is a bit confused, and I think that there are two possible things we could be seeing: 1. Quantum collapses of superpositions actually do take time ("This Changes Everything") 2. This particular quantum system is not actually being measured, but is oscillating in superposition in some odd way. ("Just a Particular System")

Which case is it?

I think it's fair to count the number of missions (it's at least consistent across engine types), though I'd probably prefer to also see the number of engine-missions as well.

But in defense of counting the number of missions, each mission has similar "external" characteristics: ambient temperature, sunlight level, burn duration, wind shear, humidity, etc. A combination of these environmental characteristics could cause a failure (Challenger failure was caused by excess cold). Since the environmental characteristics are the same for the mission, the number of distinct missions an engine has performed is a decent proxy for robust performance throughout the space of environmental conditions.

Well, not for long...

The Dust Bowl threatening people with starvation hardly seems comparable with high rents. If SF got hit by a natural disaster which destroyed the Tech community (analogous to farming as the main industry of the midwest), you bet people would leave.

I mean, it's not like it's expensive to manufacture! One person soldering and maybe a single board and usb plug, its probably easy to make money if you can sell them for $30 or so in the volumes of 100's.

I don't see this happening. The propeller physics aren't changing. If you are using the quadrotor architechure, directly lifting your playload with no wings, there's a sound-per-kg number that can't be engineered away.

If you're going to be this pedantic, 50 is greater than 48. They're not wrong.

I think younger engineers' morality towards the military distinguishes between technology for great-power warfare, and technology for bombing weddings in Yemen. Aside from some real outliers, nobody of any age wants to lose a war with China. However, it's the "wars of choice" that are problematic.

Haddington's arm is 5-axis, which is not enough to put a tool in an arbitrary position and orientation. To put a tool in an arbitrary position (3 DOF) and orientation (3 DOF), a 6-axis arm is needed. If their encoder technology is so good, why aren't they making a 6-axis arm and going right up against Universal Robotics?

I'm not certain about this, but I believe that their arm does not have a final rotary actuator on the end of the arm. If the arm is used to hold a drill, for example, that does not matter.

I don't know about the robotics community on hn, but I use the Universal Robotics robot arms for sensor testing. Sensor Testing requires 6 DOF. Current Universal Robotics arms go for ~50k, and for that you get a highly repeatable robot arm, which is also safe for operation near humans, and with a good UI.

What is so hard about the final joint, Haddington? If this is a product decision, to go with a 5 axis first to get to market first, I disagree. At this moment, 5-axis robots seem more useful to manufacturing than to roboticists and robotics hobbyists. However, I would expect manufacturing to have long acquisition cycles, and to be more willing to select an expensive, yet proven, robotics company, than to take a chance on a cheap upstart, whatever their technology.

However, if you can get a 6DOF arm to within the budget of a university robotics class or individual hobbyist, who will be willing to take a chance on an unproven robotics startup, then these people will build word of mouth about your design. Teaching the math of robotic manipulation requires a 6+ DOF robotic arm. Students who learned on a Haddington arm will go into industry knowing the Haddington interface. Furthermore, it's much more likely for a $3k arm to be within the discretionary budget of an engineering team than a $50k one.

6DOF or bust, I just don't get it.

This is right out of "The Left Hand of Darkness."

Stated goal is 4 customers per month! Are there 4 perpetually bra-frustrated people with unlimited disposable income in NYC? Hell yes!

Apparel is a different world from consumer electronics in terms of pricing.

True, but a quick look at the Space Shuttle launch configuration shows that aerodynamics, while not totally irrelevant, were _not_ the dominant concern.

Electric turbopumps are an answer to the question: "how small can you make a commercially viable orbital rocket?"

Atmospheric drag effects rocket performance less and less the larger a rocket gets (square-cube law), so that a rocket like the Space Shuttle can effectively ignore the atmosphere. Conversely, the smaller a rocket gets, the harder and harder launch gets. This is the problem Rocket Lab has decided to attack.

A decade ago, SpaceX launched the very similar Falcon 1. Falcon 1 was designed a decade ago, and you can see a large amount of the tech advancements in the last decade in Rocket Lab's design:

1. Cheap, lightweight Lithium Polymer (LiPo) batteries.

2. Cheap and performant brushless motor controllers.

3. Additive manufacturing for cheaply making complex parts without significant labor costs.

4. Advances in composites to enable the first orbital-class composite-bodied rocket.

Without any one of these advances, Rocket Lab would not be viable. It still may end up not being viable. Rocket Lab can never compete on bulk orbital cargo pricing. However, Rocket Lab's vision of applying recent tech advancements to bring down the smallest possible launcher size is extremely commendable.

Worked last night!

But, if the birds derive a significant portion of their yearly calories from eating berries during the harvest, you will still do damage to bird populations. Also, an open berry field keeps birds nearby. If the birds can't eat the berries, then what incentive do they have to stick around and eat harmful insects?

I'm not necessarily against the bird-lasers, but it's worth considering their side effects.

Defies rationality? It's perfectly rational to prefer a system of measurement that is more meaningful to you.

So I'm quite confused by this article's emphasis on boys outperforming girls more in richer school districts. If you look at the scatter plot, girls outperform boys in English by a much larger margin.

I mean, if we attribute this to the period during the Peloponnesian wars, the kids were definitely not alright. The generation of Athenians after Alcibiades definitely didn't do anything good, and Athens ultimately lost the war.

As a github user, i don't see any way the acquisition could possibly make my user experience better.

I don't use any microsoft tools (and I _hate_ all windows after 7), so Microsoft integrating with GitHub has no appeal to me.

I think the best case scenario for me personally is that nothing changes. None of the github changes in the past few years have added anything noticeable for me (not sure if others agree, be interested to know). And the best case scenario being "nothing changes" is pretty damning. I know it's overwrought, but Skype was perfect, and 2010s-Microsoft fucked them up. And if we're seriouslyhaving the best case scenario be "nothing changes", that's bad.

And it also just seems part of the bullshit mindset of startups being about the exit, and not about making a new, sustainable company.

GitHub didn't need to do this, but they did, to justify their reportedly insane burn rate. Microsoft still won't let them get away with that, they'll just take the heat for the inevitable layoffs.

It's just fucking depressing all round.

Well, Github execs could do the responsible thing and cut costs. But that sounds hard, and like it would require effort, so here we go. It's sad.

The delta-v also depends on the mass fraction you can achieve. Removing the tanks might mean a much higher mass fraction, so you have the same delta-v with much lower Isp.

How are they going to get a good seal around the rod at it was being consumed? That sounds like it would limit the thrust the engine can achieve.

One thing i saw was that the rocket can throttle, presumably by changing the rate at which the fuel rod is moved inwards.

Why does GitHub need to be acquired at all?

Do the costs of running the servers and hosting the free services not cover the revenue from Enterprise users?

I believe that any Enterprise users won't notice even a doubling of the subscription fee, if GitHub really needs it.

I don't know why there needs to be more than a handful of employees working at github, just don't break what's already there!