As pretty much anyone who offroads knows, AWD vehicles absolutely tear up the trails vs a proper 4wd with lockers, since AWD relies on detecting tirespin (ie, destroying trail) to determine when it needs to activate.
AWD can theoretically work far better than a 4WD with diff locks, because it can simulate, based on the steering wheel angle, the exact speed each wheel should turn, and 'lock' each wheel to that speed giving zero slippage.
Just a shame that the sensor -> computer -> actuator feedback loop seems to be 200 milliseconds or more, so AWD vehicles just end up having different wheels slip semi-at-random till that wheel gets the brakes activated 200ms later.
It’s not just sensors. It’s mainly to avoid it falsely applying itself. In my opinion, that is far more dangerous because it’s wildly unpredictable when it will work as expected vs when it toque vector.
I can get the torque vectoring to do some weird things, kind the right conditions on my car. It’s okay because I’m intentionally pushing the limits, but I absolutely would not want the vectoring to kick in when I’m not expecting it. Towing on packed snow/ice is not the place you want to learn your wheels suddenly decided to react dramatically differently.
Most AWD systems do not have the ability to vector torque like that. They're usually based on mechanical limited-slip differentials that require some amount of slip before they partially lock, and sometimes the limited slip is only between front and rear, not left and right. There are different types, with some requiring a lot of slip before they lock up and others requiring little.
Limited slip differentials cost more than open differentials. Limited-slip differentials that lock up quickly cost more than those that allow a lot of wheelspin. Electronically-controlled torque-vectoring differentials cost yet more.
The system you describe seems to meet the NPS definition of 4WD someone linked elsewhere: "a means to mechanically power both front and rear wheels at the same time", though I wonder if there might be some more technical regulation with specific requirements. I agree that sort of thing could work well for off-road use.
NPS defines 4WD specifically as part time four wheel drive with a transfer case and low range, FWIW. Low range is a big part of it. And yes, their definition technically excludes higher end "full time 4WD" systems in some cases, though I suspect everyone would look the other way at those.
A quick web search didn't find a formal definition, only information pages for specific parks with descriptions. I agree it's likely park rangers would use common sense in practice such that a vehicle with an extremely low first couple of gears, lockable differentials, appropriate clearance, and suitable tires wouldn't get cited as "not 4WD" because it doesn't have a selectable 2WD mode.
Incidentally, I once owned a Subaru from the 1980s which had a lockable center differential and separate high/low gearshift, which was synchronized and could be shifted in motion. It was not designed for serious off-road use, illustrating the folly of relying on criteria like these.
> A Jeep, sport utility vehicle (SUV), or truck type with at least 15-inch tire rims and at least eight inches of clearance from the lowest point of the frame, body, suspension, or differential to the ground. Four wheel drive vehicles have a driveshaft that can directly power each wheel at the same time and a transfer case that can shift between powering two wheel or four wheels in low or high gear. All wheel drive (AWD) vehicles do not meet this definition.
I completely agree they'll use their discretion, but either way, that definition is specifically a part time 4WD system with low range.
AWD has come a long way in that regard in the last few years. It's still highly variable from manufacturer to manufacturer, but systems that use internal clutches alongside brakes (and not only brakes) to control wheel movement + tight feedback loops can really do a great job of minimizing wheel spin.
They get a lot of hate, but the bronco sport has the best AWD system I've driven to date in that regard.
And with that said, it is still the type of thing the Park Service would rightfully cite as not a proper 4wd. 9ish inches of clearance is not much, and the lack of a low range will bite you. I've taken mine on plenty of milder 4wd only trails in parks (e.g. black gap in big bend plus tons and tons of forest service roads), but I'm certainly not going to do elephant hill in canyonlands with it. That's what the dedicated off-road rig is for.
There are "4wd only" trails in national parks that high clearance AWD is fine on. The rangers will tell you which ones those are.
Canyonlands is a different beast than most national parks. Canyonlands has some very gnarly trails open if you have a permit. Lookup dollhouse sometime. Beautiful, but insanely technical. Elephant hill is better known and a bit milder.
From their report of "the little three-, two- and (very occasionally) one-wheel-yeet maneuver", it sounds like the lack of suspension travel was the main issue. The details of your AWD or 4WD system don't matter as much if you can keep your wheels on the ground.
Still, just because they were fine doesn't mean someone else would have been. The main risk seems like doing a somewhat technical, off-the-beaten-path trail alone regardless of your vehicle's capabilities.
Yeah, I came across that earlier. Definitely impressive!!
I completely agree with your general point (articulation matters a ton!) but I have to take a bit of issue with:
> "The details of your AWD or 4WD system don't matter as much if you can keep your wheels on the ground."
That's where the details of the system matter the most. Getting torque to a single tire is the hard part and the reason folks focus on it so much. A _very good_ AWD system can get enough torque to move the vehicle uphill / out of a tough system to a _single wheel_. Most can't. Most traditional part-time 4WD systems can't either. Open front and rear diffs are the norm in "true 4wd". Locking rear diffs are starting to become commonplace, but only a few stock vehicles come "triple locked" from the factory.
I grew up wheeling an old mid 80's S10 Blazer. Fun, small, fit down trails well, had the "holy grail" 100" wheelbase. Solid rear axle + IFS. Manual transmission. Good (enough) articulation. Plenty of clearance. Big enough tires. Crap horsepower. Worse gas milage. "True" part time 4wd with a transfer case (i.e. would 100% meet the NPS's definition in this case). But open front and rear diffs. I got stuck every time I got a tire off the ground.
I've taken the little bronco sport plenty of places I tried but could never make it in the Blazer. (And to be fair, vice versa... Big muddy ruts are not something I want to put the sport through for clearance reasons, and that's kinda what the Blazer did best.) At any rate, good modern AWD can often beat traditional part time 4wd with open front/rear diffs when wheel lift comes into play. On the flip side, independent suspension all around means it's going to lift tires _all the time_, so it _has_ to be good at it. Most AWD systems unfortunately aren't, even though some are these days.
Odd take, golang was designed by Google for their needs. It has very little uptake amongst hobbyist devs and is nearly entirely used by professional devs. In my experience hobbyist devs focus primarily on javascript/python.
But don’t have to cobble together a bunch of arcane iptables commands and then combine bpf and other userland tools … when one can just use the clean syntax of PF especially for home use that’s a clear win.
I've used both extensively and I find eBPF+iptables (and sometimes nft) significantly more flexible and easier to use in the real world (not just simple examples) than PF. shrug
I have -- I let the OpenBSD firewalls take care of it :P
Seriously though it's something I need to get familiar with, I do still have plenty of Linux boxes that face the public Internet and are currently dependent on iptables/ip6tables rulesets. The problem is I'm currently masking that pain with Ansible.
There is definite lack of a declarative tool that glues it all.
Typical hardware switches and routers just have one (sometimes expanded by includes/macros but still) config syntax to control every part of networking stack.
So you can configure interface and set its vlans all in one place instead of creating a dozen of ethX.Y devices then crerating a bunch of brY bridges and then attaching the interfaces to them
In linux instead you'd be using iproute2 set of tools to configure interfaces and static routing, iptables for IP ACLs, ebtables for ethernet ACLs (or now nftables I guess), without any tool to apply/revert changes at once
Many tried doing that but IMO haven't seen anything good.
Many also try to "simplify" iptables and all it ends up is me being annoyed coz I know which iptables commands I need to run but I need to translate it back into "higher" level config syntax. One exception being ferm ( http://ferm.foo-projects.org/ ), because it keeps iptables-like keywords just expands on that, but it is iptables only and kinda superseded by nftables syntax anyway.
iptables/ebtables is deprecated even in RHEL. While people are free to continue not to transition to nftables complaining about problems with iptables after a decade of its replacement is a bit silly.
As someone who spends a lot of time working with DPDK, the idea that anyone would consider userspace "slow" and kernel of all things "fast" is amusing to me.
Most everyone nowadays seems to try to avoid kernel as much as possible, since it's vastly slower than a userspace forwarding plane (although eBPF/XDP will likely change this).
Maybe because I've worked in embedded Linux for so long (including on inits of various forms), but that description clearly articulates exactly what systemd is and does and I appreciate the direct, crystal clear technical language rather than some long form essay written assuming a clueless reader with 0 technical background.
You’re pulling my leg, right? The description could be improved, for starters, by forcing the author to not use the word “object.” That overuse alone makes me wonder if the description is satire.
I expect everyone here commenting is familiar with systemd. I doubt very much that anyone who was unfamiliar with systemd and read that description would then have any idea what it does or how it works.
I mean, I'll agree with you in so far as that the wording could be improved further. But I do really, honestly think it's a good summary.
> I expect everyone here commenting is familiar with systemd. I doubt very much that anyone who was unfamiliar with systemd and read that description would then have any idea what it does or how it works.
It depends on what knowledge you expect. If someone is familiar with general init management and some programming concepts, this short summary will get them up to speed (and that's what I/we were arguing). If you grab a layperson of the street and read them this, it's obviously not going to tell them anything - but that's not the target audience.
What I value is a short summary which brings a reader, who knows the concepts and the space a software is operating in, up to speed quickly. And that's what this summary does.
> Failed as in the vaccines, that were being advertised as being 95% effective with no talk of any boosters only 6 months ago, no longer provide any protection at all.
It's disappointing to see complete lies like this on HN. Vaccines have been, and remain, incredibly effective in preventing hospitalization/death, even without a booster (although everyone should also get their booster).
And why do we think that? Because public health agencies said so?
It's not because the trials proved it - they didn't. At only ~64,000 participants the e.g. Pfizer trial was not powered to show any difference to deaths and didn't use hospitalizations as a goal metric either, only infections.
And so we're forced to rely on the testimony of the same people in charge of the program, where their data is often missing or deceptive in some way. For example Germany has been claiming nearly all cases occur in the unvaccinated. It turned out this wasn't true. Rather, they don't have data at all on the status of most cases, and then reallocate all the "unknown" column to "unvaccinated" because ... well, why not? No matter what they do, plenty of people will still take their word for everything. This was revealed by Die Welt and the response was nothing. They still do it, as far as I know.
The UK data is usually considered to be the best, as in, the most detailed. And there, when the data on deaths is studied carefully it turns out to be riddled with anomalies and problems that cast doubt on whether vaccines did in fact reduce mortality (the numbers are low enough that statistical artifacts can actually matter). For example, in the UK data vaccination reduces non-COVID deaths in unvaccinated people. Don't take my word for it, ask a professor of risk management:
"Our research team have now analysed the ONS England November mortality data. We conclude that, despite seeming evidence to support vaccine effectiveness, this conclusion is doubtful because of a range of serious inconsistencies and anomalies", "The ONS data provide no reliable evidence that the vaccines reduce all-cause mortality."
I don't have to trust public health agencies. I can go look up the numbers in my local hospital or ask family members who work there. >90% of ICU cases and deaths are unvaccinated. Hand wavy arguments about "the data is bad!" from a non-peer reviewed paper with 0 citations does not convince me that you're arguing in good faith.
If your (English) family are telling you that then I wonder when they said it because the official figures were just updated and say >50% in ICU are vaccinated now. It's been changing over time because the vaccines wear off so fast.
In the case of my numbers, I'm based in the US. I wish we had a high enough vaccination rate to worry about the base rate fallacy. I'm surrounded by rural areas who unfortunately don't believe in vaccines until they show up in the ER. We have an enormous surgical backlog due to antivaxxers having filled up the hospitals for months on end.
How bizarre. You're the one who brought up that stat in the first place, I'm only pointing out that it's incorrect, at least for the UK - and the US isn't going to be very different. There's no base rate fallacy here because I'm not even building an argument on that data to begin with, you are!
"We have an enormous surgical backlog due to antivaxxers having filled up the hospitals for months on end."
You have a surgical backlog because your hospitals have been firing staff. Former "heros" who, quite sensibly, observed that as they'd already had COVID they didn't need a vaccine for it, and who were immediately demonized and excluded despite the hospitals supposedly being overwhelmed. You might want to meditate on that and consider whether that's the expected course of action during a crisis or not.
I get the feeling you are getting your information from highly political sources rather than getting out from behind the screen and talking to real live people.
Where I live, there is no vaccine mandate for hospital staff due to staffing concerns. Talking with actual local physicians, nurses and doctors are quitting in droves after seeing a huge amount of preventable death in the past few months, by patients who deny the reality of the disease they have, and whos families harass hospital staff about treatments that don't work (hcq/ivermectin/whatever the latest magic pill is now).
I actually am against vaccine mandates and don't think anyone who doesn't want the vaccine should be forced to take it. That said, if you don't take it, I don't want you in the hospital if you end up getting covid. Take hcq/ivermectin/whatever joe rogan is saying now rather than occupy a hospital bed, don't clog up the hospital due to your mistake.
There is no conspiracy theory here. Stop using that term to minimize the importance of things. VAERS is a data point. Check out similar data points from other countries. Numbers DO match.
What other data points? Can you provide peer reviewed high quality data to support your claims? Just because you want a conspiracy theory to be true does not make it so.
Can _you_ provide any other legitimate data point that tracks adverse vaccine reactions? Most likely not. Because the narrative is such that if there is anything negative comes out, people are immediately being canceled or fired.
What Honda element had 4wd? As far as I'm aware they were all (a pretty bad) AWD system.