XeroxCool

@XeroxCool@lemmy.world
0 Post – 346 Comments
Joined 1 years ago

There's 2 significant inaccuracies in the article and 1 large oversight in the official video.

  1. Differentials are not one wheel drive. They can seem to drive only one wheel when spinning the wheels as one let's loose and the other stays still, but it's not driving one wheel. It's still driving both. The problem is the free wheel is spinning at twice the speed indicated on the speedometer and the other is at 0. The driveshaft puts in a certain number of turns, the wheels, together, must add up to an equal output (multiplied by the gear ratio). If the car is going straight with full traction, then they turn the same. If you floor it in snow, one is probably spinning 40% over it's share and the other 40% under. This is not unique to rwd either as fwd cars still very much have a functioning differential. To throw some numbers at it to help clarify the function, let's say the engine is asking the wheels to spin at 30rpm each in a straight line. In a left turn, the right wheel travels further and needs to spin at 35rpm while the inner spins at 25rpm. It still adds up to 60rpm, same as a straight line. Mash it in the snow and it might be 60rpm in the left and 0nin the right or 0 in the left and 60 in the left. It could be 5/55, 40/20, or any other combo as long as it totals 60.

PS: differentials are irrelevant when the wheels aren't connected to each other. Individual-motor wheels, as shown in the video, don't need a diff. The non-drive wheels in a 2-wheel drive vehicle do not have a differential on the non-drive axle.

  1. Cv joints are not specific to fwd as nearly all modern rwd cars with independent rear suspensions have CV joints. I don't know of any trucks still using U-joints either since big trucks are solid axle. Cv joints function the same as U joints. The difference is C.V. joints output constant velocity whereas U-joints (what you'll see often under trucks on the driveshaft, two square C shaft ends with an X link between) have lopey output that gets worse with greater deflection angle. If you own a u-joint bit for your socket wrench, I invite you to play with it. Instead of a solid pinned X between the U ends, CVs have free-rolling balls that can roll inboard and outboard to maintain the link between the shaft's cup and the wheel's cone.

  2. The article is inaccurate but the video ignores this part, so I don't fault The writer. The CV joints are said to be a poor design, yet, it ignores the part where the video reinstalls them at 4:20 and 5:10 for the front wheels. This mechanism does not allow angular deflection between the motor and hub, as it's shown, without a CV joint. Lateral displacement, yes, but not angular - as in it can't steer. This may be an overall improvement by reducing how often it needs to bend (only when steering), but it doesn't eliminate it. And even then, the rear suspension is still designed to change camber as it changes ride height. Camber is the angle of the wheel as measured top to bottom, as in what you see from looking at the wheels from the front of the car. It keeps the wheels flat on the ground as you lean the car in a corner. You may see an overloaded car's rear wheels look like /---\ as viewed from the rear or ---/ when hanging free on a lift.

Look, I'm not an engineer at Hyundai (or even a competitor) but this doesn't quite pass the sniff test. Cool idea for sure, but it smells a little like marketing is clamoring for something edgy to display. Even as displayed, the motors and original reduces were already very compact and in close proximity to the wheels compared to a normal engine. The slightly reduced footprint of this uni wheel and slightly increased friction of a bunch of additional gears makes me think this is a fractional improvement in practice rather than a revolutionary improvement.

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So they want to change their identity based on the feelings and bend existing geo roles to match?

That's the neat thing. The speed of light is constant. It doesn't change. It's always 1c whether you're traveling at +1c, - 1c, or 0c. Buckle up for some relativity. The wavelength can compress or expand, but it always travels at 1c.

Let's say you're on a ship capable of moving at any speed between 0c and 1c. You're passing a particular star and want to travel to a planet 1ly away. You have a powerful laser and the other planet has a powerful telescope to detect it. There are calibrated timers on both the planet and on your ship that are synced to each other. .

T minus zero. You flash the laser at the planet as you fly at 0.5c, or 1/2 lightyear per year. The light travels at 1c, or 1ly per year.

1 year after the flash, the planet sees the flash. It traveled 1ly in 1 year. 2 years after the flash, the planet sees your ship arrive. All is normal so far.

From the ship, you know the light traveled at 1c away from you. You arrive at the planet 1 year after the flash, according to your on board timer. One. The light took half as long as you.

Time is not constant, c is constant. The faster you go, the slower time passes. In 1 year of fast travel, you arrive 2 years later, according to the stationary planet. So all of the light physics apply the same, no matter the speed. Time dilates to make up the logical difference. If you reach 1c, time effectively stops and you arrive instantaneously, from your perspective. When we look up at the Andromeda galaxy, some 2.5 million lightyears away, the light we see was emmited 2.5 million years ago - from our perspective. If we see a star go supernova in Andromeda, it happened 2.5 million years ago. But those photons of light, created by a star that died 2.5 million years ago, experience no time passage at all. They instantaneously go from the star to your retina, from their perspective.

That's basically why lightspeed travel is effectively impossible within our current models. Traveling faster is out of the question because none of it makes sense. It's not a simple matter of making a new model or believing scientists are idiots. There are many experiments that hold true to the model (such as the atomic clocks used on a plane to test the effect of speed and gravity on time dilation) as well as satellites using the current model to maintain time accuracy. The energy required to get to those speeds is not even remotely feasible. The fastest man made object at 450,000+mph, the Parker solar probe, is still in the 0.0005c range. We tried our best and it's still just a tiny fraction of 1c. And that's by using some gravity slingshots and spiraling down into the sun's gravity well, nothing about leaving the solar system. The Voyager probes that slingshotted out of the sun's gravity well are down to under 40,000mph.

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Amazon is still sketchy with legitimacy of product. Fake product can get mixed into legit bins of product if the main seller doesn't pay extra for dedicated bins, separate from other sellers selling "the same" products.

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You can see on the left where they tried then realized it was way too big of a task. I probably would have tried a little harder to get some white in the right spot, but definitely not perfectly. Not even close. I ain't mad

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RIP. Rest in Interstellar sPace

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There's a model X near me with a bumper sticker that says "we bought this before we knew Elon was crazy"

2x2PT has been 1.25x1.25 for as long as I can remember (10 years or more). It's only the pressure treated deck stuff for railings. This does not apply to the rest of the 2x lumber, as those are still 1.5 actual. I got Simpson corner 2x2 brackets for crazy cheap way back but ended up not really using them. The 2x2s are warped to hell and a ripped 2x4 was too big in the original 2x dimension.

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"I didn't really understand the technical aspects, which is why I turned to a technical service I also didn't understand"

It's frustrating how many people have security lights aimed wrong. They're often aimed high, wasting light to the sky, and they're often mounted low, blinding you walking into your own home and leaving you vulnerable.

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Good thing Intuit (TurboTax) is fighting so hard to keep the current format super slick and cheaper as a private service rather than a centralized government process. Right up there with disbanding garbage pickup in favor of individually contracted services because [checks notes] 7 overlapping truck routes will be cheaper than 1

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Discover offers monitoring. How are you so sure it's phishing? An abundance of caution and logging in directly is certainly a safe route to verify, but convincing OP this is phishing and that the graphics are risky is unnecessarily alarming

I thought his jeep issue was that P on the dial didn't actually guarantee the parking pawl was engaged to stop it from rolling. Separate from the lack of positive engagement with the P position, more about the physical disconnect between the two. Unless that was just the non-offensive language version of "user didn't turn the dial all the way and our polite warning chime was too polite"

Not really. They want nonwhite unhappy people to leave the country, not change it to their liking. So to comply with their own shoutings, they'd have to physically move to Idaho, not just reroute state borders to their liking.

State borders are fucking dumb under the "one nation" notion. It's 50 colonies in a trench coat, pretending it's different than the EU

The mental gymnastics are in response to copyright holders' gymnastics. They remove content, relocate it, put it behind tiered subscriptions, or sometimes effectively delete it from all legal avenues after owners/subscribers paid for it. So if paying for a subscription isn't owning it, as described in Amazon's fine print for example, then what do you do? It's a long-term rental subject to removal upon any licensing transfers. Sure, we get greedy once set up, but if legal options don't actually offer you any legal ownership due to legal gymnastics, then yeah, I'll do the mental gymnastics right back at them.

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It's 50 states in a trench coat

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Automation already took most of the mine jobs. The majority of US coal comes from the west where mines are on the surface, equipment is larger, and the coal has lower sulfur. If coal ramped up back to full production, the mines would hire back only a small fraction of the displaced workers.

The Milky Way may be closer than you think. I had never really seen it until a few years ago. I was in my usual darker spot and took a picture of it with my phone's astro mode. I looked back up and suddenly, there it was. I just never knew what to look for or, more importantly, just how big the visible structure was.

I recommend taking a look at lightpollutionmap.info and seeing what's around you. I'm in a major city metro but dark-enough skies are less than 2 hours away. The Milky way revelation was in a "Bortle 5" zone (red on the map). Cities are class 8+, oceans/uninhabited is class 1. Constellations help you find the core (namely the tea pot/milk dipper asterism) and knowing what time of year/night to look is important. August is the usual ~10pm month but you can go out later at night earlier in the year and vice versa from about April (close to sunrise) to October (near sunset).

Be aware you need to adapt your eyes. Pupils dilate in seconds but the 20 minute thing comes from replenishing rhodopsin in your eyes. White/blue/purple light bleaches that compound but red doesn't. With enough commitment and knowledge at that same place, Andromeda becomes a naked eye object for me. Extremely faint and just a smudge, but unmistakable.

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Or the movie was based on real life. Animals aren't as dumb as we pretend. Other mammals are just that: mammals. The same as us. Mammals have the same feelings as us, the same emotions, the same fundamental chemical reactions, the same socialization. We just have big brains and written language to amplify basic mammalian traits.

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Edit: I jumped over a detail in my memory. The ground pin goes to neutral in the breaker box and neutral is grounded. The key part is that the ground pin isn't an isolated circuit that just goes to the dirt. I'll leave the below so you can see what people were correctly arguing with me about.

The ground pin in a north American outlet, at least, isn't actually grounded. It's just a dedicated circuit that goes back to the neutral line in the circuit breaker box. It doesn't go to the ground there, either. Not to mention you don't get static sparks when touching dirt anyway because ground is a terrible conductor anyway - it works on a power delivery scale because it's effectively infinitely big. These things only vaguely work for static reduction by being large metal structures that can sink the excess static. That's why doorknobs and coat racks happily shock you.

No, the "ground" in a car is not actually a ground at all. It's a chassis common power point. Ground is the entirely wrong term but people will argue it up and down because it has always been called ground. Mixups in function like this are exactly why I'll argue to use the right terminology. Common supplies power by chassis. Ground sinks stray power away from the device/fingers (hence why I don't argue against calling a house ground a ground).

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Elite: Dangerous has lots of players that complain all day and play all night. Probably EVE too

What you're posing as a counterpoint to potentially not being able to recycle paper products, we should automatically go straight to cutting down more trees.

Imagine making paper on your own property. You have two trees. You cut down one tree, plant a replacement, and make 100,000 sheers of paper product. When you're done with a sheet, throw it in your yard. It's composting, right? Sure. You've made no efforts to recycle clean paper. When your 100,000 sheets run out (printer paper, note paper, toilet paper, and paper towels), you have to go cut down the second tree. How big is that replacement tree? Is it going to ready 100,000 sheets later? Will it get struck by lightning, caught in a wildfire, hit by a car, or catch a disease? You'd hope not. So wouldn't it make more sense that, even though you're planning to replant trees, to recycle as much paper as you could? You wouldn't have a yard full of composting paper and you wouldn't have such a close dependency on your two tree plots. No, this isn't solved by having a whole forest available when you scale up the consumer side too.

Now consider that an average American consumes 7 trees per year and a tree takes at least 20 years to mature for processing. That's 140 trees growing simultaneously to support one person.

So no, we can't just blindly throw all our paper in a landfill and ignore the impact. Why so many places do single stream with tuna oil soaked into paper, I don't know. I get the frustration.

Metal isn't so clean either. Every time it gets processed, more and more is lost to oxidation and to contamination during smelting. Sure, it's more easily recovered from the single stream can, but I'm not a fan of metal newspapers

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Sails fell out of favor because when people order something, they want it immediately. Sailing was too inconsistent and petroleum became too cheap. There's still a huge shipping market for overnight intercontinental flights for companies who can't wait. I'm happy to introduce hybrid propulsion systems to try to make a dent, but we can't pretend it's an altruistic effort. We can't pretend customer demand is why these ships are so dirty in the first place, either.

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Saved you a click: customer paid $514 for $435 worth of groceries, not including fees and tip. $79 is "almost $100" and is about a 16% markup

I don't know what this is, so I just read it. OK... OK... Fine... What? what? Oh no. What a ride. Still don't know what it's purpose is, but damn.

That's not correct. FMVSS 108, Table I-a, specifically allows rear turn signals to be amber or red. Front turn signals must be amber only.

I'm sorry for your loss and don't want to take away from that significance, but I'd like to share some info. Just for general info so people can know what they're seeing. Vision loss isn't necessarily obvious to a fully-alert person. It's not a black void in your vision, it's a lack of image. A lack of image means a lack of signal, so your brain doesn't see nothing, it processes nothing. You may be able to recognize a lack of vision if you know something is supposed to be there, but your brain will try to stitch together the information available. Point in case: both of your eyes have a blind spot a little up and a little outward from the center. It's not just covered by your other eye because you still don't see it when you close one eye. You can search it for a picture that partially disappears when getting closer.

I get occular migraines that involve distortion followed by central blindness in one eye. The "faces" I see are incredibly unnerving during those episodes. Last time, basically a 2" diagonal slice was removed from peoples faces at conversation distance from forehead to ear. Not a black spot, just gone with the remaining image stitched back together.

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Aza.org/jobs?job=40977

Animal Educator/Tour Guide at Colorado Wolf and Wildlife Center, Divide CO. Accredited by the Association of Zoos and Aquariums. I might be missing something but I think neither CWWC nor AZA is a government entity.

The screenshot skips the perks which include a vest when promoted. They claim you can also do a bunch of related training/school at no cost to you but I feel like those benefits are usually hard to get and/or balance while still being a useful asset. But of course listed perks include multiple types of experience.

As with many animal-related jobs, the low pay probably manages to automatically filter down applicants to only compassionate people that just want to help the little floofs. It's a step above volunteer (of which many are present anyway).

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I didn't beleive it would but it did

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Why do people always feel like their inexperience on a topic is relevant?

Probably to politely invite contrasting opinions and experiences from people in the field

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Companies love subscription pricing and customers keep it up. Lots of software went this route and proved people still want the product. It shouldn't be a surprise

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It's a situation where there are benefits to either option but one probably outweighs the other massively in frequency. I schedule many more international meetings and make many more international calls than the number of times I've needed a global event time. And that's kinda saying something since I'm a space geek that looks for astronomical events, which are all UTC. It's fewer steps to look up the distant current time and do the math from my current time for a passive event than it is to have everyone be UTC, then look up a distant wake time or business hours, then do math to figure out what the functional time is for something requiring human input.

China is one universal time despite spanning from +5 to +9

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Fun fact: the average laser's collimation expands to the size of a football field by time it reaches the altitude of the ISS. The moon is 1,000x further. Despite the higher refinement of the laser used to bounce light off the retro reflector, it still takes an incredibly strong sensor to detect the bounce back. It's not how The Big Bang Theory portrays it.

Now that this party is pooped, the sun is still stronger than anything we can beam. It might trickle charge. The rays that decrease exponentially with distance, coming from. 93 million miles away, still roasts us. Solar power is insane.

Edit: astronomers did actually beam a laser and get seen by the ISS. They used a very powerful, focused blue laser and tracking software to aim it on a powered mount. The tracking was necessary because they had to shine it when it was not illuminated. When we see the ISS lit in the night sky, they're in full sun. The astronaut, Don Pettit who has an extensive photo portfolio, reported seeing a dim, flickering blue light coming from the ground and got a picture. He also saw the spotlights flashing. https://www.universetoday.com/93987/amateur-astronomers-flash-the-space-station/

Your info was probably already out there, somewhere. It's most likely in a massive list with thousands of others. It's still not great, but you're not being targeted. This is why it's important to freeze your credit with each bureau.

Just another reminder that using your SSN for ID verification purposes and acting like it's a secret code only you could ever know is a dumb fucking system. Even the "verify with your last 4 digits" is a dumb fucking system. If you have a date of birth and a decent idea of birthplace, you can take a pretty good guess about the first 5 digits because they're sequential from known blocks. It wasn't until about 20 years ago that the government randomized the first 5 to stop that.

Honey Oats & GetTheVacuum

That page doesn't exclude commercial road vehicles or interstates, so the apples to apples comparison may be much closer to the autonomous rate. A 700 mile/day truck cruising I-40 through the desert is going to skew the data as safer while I bet a casual city driver will be an order of magnitude more dangerous. Maybe the best would be stacking it against taxi and other ride-hail drivers

Edit: Cruise didn't even cause the incident. A human-driven car hit the pedestrian into the Cruise. This sky-is-falling reaction was started by a human doing worse.

So they do a series of very precise, complicated drive cycles (with a few different options of which cycles and fuzzy math multipliers) to estimate a number that people will never reach because they're doing 80mph. But somehow to anti-ev people it's only electric range that is an unforgivable lie, not ambitious MPG ratings. It seems like a disadvantage to use a different rating system but I guess you can't trust the gen pop to understand MPkW since they can't picture a bottle of 1kW

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Including 2 digits for cents, for those referencing their dream of 6-figure income

No, everyone needs to pay their fair share of taxes. No freeloaders and no cheats gaming systems like unemployment! But remember, if a very wealthy individual says mean things that get you aroused and they game the system, it's financial smarts. And if tips go unreported for a person you resemble, that's just what everyone does. And if you time retirement/ss to double-collect benefits and pay, we'll you didn't write the rules, right?

"no, not like that"