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Subjunctive posted:My car automatically controls high beams, if told to. It's still two (and only two) distinct settings. At this point lights should either be on or off, otherwise adapting the beam to road conditions.
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Jan 25, 2018 00:06
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bull3964 posted:It's still two (and only two) distinct settings. People around here haven't managed on yet, even when it's snowing or pouring rain.
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Jan 25, 2018 00:30
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Charles posted:People around here haven't managed on yet, even when it's snowing or pouring rain. (that's why he's saying it should be automatic)
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Jan 25, 2018 00:34
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bull3964 posted:It's still two (and only two) distinct settings. And by “either be on or off” you mean “always be on”, I assume. The safety data is pretty clear, I believe.
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Jan 25, 2018 00:35
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More important for good headlights than what technology is used, is how much effort the manufacturer is willing to invest to make good lights. I believe most HID or LED headlights on the market still can't beat the best H4 lights Saab or Volvo had decades ago. One practical limit for low beams in EU nowadays is 2000 lumens, if the lights produce more than that they will need to be equipped with washing sprays and many models, even luxury ones like current M-B E-series, don't bother with that. But the feeling I've got from reading headlight tests in finnish car magazine from recent years, is that on average the LED lights are slightly better than HIDs. So that would indicate that it cheaper or easier to produce good lights with LEDs. Still the most important thing is manufacturer effort. Nice example is Alfa Romeo, where the Giulietta had significantly better lights than the more expensive Giulia. Another good example is Opel Astra. If a <25k € family car can have full LED adaptive matrix lights, then there is not much reason to not have LEDs as an option. The IntelliLux LED Matrix has 16 separate LEDs. You can keep the high beams on and the car will automatically turn off those specific LEDs that would blind the oncoming car or the one driving in front.
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Jan 25, 2018 01:27
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Three Olives posted:Lower power, lower weight, smaller, longer life. Truck-lite makes LED headlights (housing+bulb) with a heating filament in the lens. It kicks on at something like 40*F. And adds something like 40% to the cost.
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Jan 25, 2018 03:47
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Subjunctive posted:And by “either be on or off” you mean “always be on”, I assume. The safety data is pretty clear, I believe. Sure is. NHTSA posted:The analysis evaluates the effects of daytime running lights (DRLs) against three types of target crashes: (1) two-passengervehicle
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Jan 25, 2018 03:49
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Godholio posted:Truck-lite makes LED headlights (housing+bulb) with a heating filament in the lens. It kicks on at something like 40*F. And adds something like 40% to the cost. Part of the reason that automotive LEDs are tricky is because of temperature requirements. HIDs and halogen incandescent bulbs are both pretty insensitive to temperature -- they get very hot in operation and just kinda stay there, stably emitting light, regardless of the environment. The brightness of an LED, though, is directly related to the temperature of the semiconductor junction. A hotter junction is less efficient and produces less light, and vice versa. LEDs do produce heat; not as much as the other options obviously but it's still there, and enough to damage the device if it's not removed. Problem is that it's created right at the junction and usually radiated out the back, so the heat has to be removed but can't be used to melt snow. And you also have the opposite problem -- when the junction is cold, it will become more efficient and produce more light. So on a hot day you need cooling in order to keep the LED from going dim and burning up; on a cold day you need heating to stop it from producing more light than is legally allowed.
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Jan 25, 2018 03:56
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I guess because there's no statistical data on near misses in automobile transport, they just ignore that factor completely then. Like no poo poo in all cases where there was a crash, lighting made no difference. You keep your lights on to avoid a crash in the first place.
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Jan 25, 2018 04:49
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Finger Prince posted:I guess because there's no statistical data on near misses in automobile transport, they just ignore that factor completely then. Like no poo poo in all cases where there was a crash, lighting made no difference. You keep your lights on to avoid a crash in the first place. It looks like they were looking at whether DRL-equipped cars were in proportionately fewer collisions, which I think would capture that. It’s not what I recalled, but there it is.
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Jan 25, 2018 09:14
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This one from NHTSA 2000 found some positive effects: http://www.lightsout.org/docs/DRL7_RPT.pdf Another one with small, positive effects: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2850978/ This Norwegian article (DRLs are mandatory here) summarizes a number of papers, most with positive effects: https://tsh.toi.no/doc677.htm I'd say 1) this measurement is difficult and 2) DRLs are nice. Lights on or off is like a beacon on an airliner, you can see them much further away and it lets you know that this vehicle is operational and doing stuff in traffic. Many EVs have a thing where they switch off the rear lights, I suppose to save power, and then a light sensor switches them on again when it's dark, for instance in tunnels. But obviously, even this basic level of automation is hard to get right so I often see cars with no rear lights in dark tunnels. Since LEDs are so efficient, why bother?
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Jan 25, 2018 10:20
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I still don’t get why DRLs don’t also switch on the tail lamps - I see way too many Commodores and Toyotas with their over-bright DRLs only on in near dark conditions.
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Jan 25, 2018 19:18
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Rear DRLs would probably be detrimental to my driving safety. Red is not a color that jumps out to me and in the bright daylight I'm going to be better off looking at the difference between off and on state for brake lights at a distance rather than on and on brighter. It's not an issue at night since contrast is so much higher then.
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Jan 25, 2018 21:24
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I wish they would get rid of DRLs so idiots stop (I see multiple every time I drive at night) driving around with their DRLs on and the dash lights blasting them in the face, no clue that their lights arent on.
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Jan 25, 2018 22:05
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dissss posted:I still don’t get why DRLs don’t also switch on the tail lamps - I see way too many Commodores and Toyotas with their over-bright DRLs only on in near dark conditions. D C posted:I wish they would get rid of DRLs so idiots stop (I see multiple every time I drive at night) driving around with their DRLs on and the dash lights blasting them in the face, no clue that their lights arent on. With all the laws designed to ensure even the brain-dead can safely operate a motor vehicle, you’d think by now they would have outlawed dash lights coming on without the headlights. I’d say a solid 10% of
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Jan 25, 2018 23:05
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On most modern cars, if drivers would leave their headlight switch in the auto position they'd be fine.
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Jan 25, 2018 23:32
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Ok this looks pretty good. https://twitter.com/Carpervert/status/956669251947040768
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Jan 26, 2018 00:31
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Ola posted:Ok this looks pretty good. That does look great. But its definitely not a shooting brake, its a wagon, it has 4 doors.
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Jan 26, 2018 01:25
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I had to google "shooting brake" and drat if that isn't the most British term possible for a wagon
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Jan 26, 2018 01:29
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kill me now posted:That does look great. But its definitely not a shooting brake, its a wagon, it has 4 doors. Drive it for a few months, the rear doors will stop working eventually.
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Jan 26, 2018 01:49
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Ola posted:Ok this looks pretty good. I guess I'll go against the grain and say that no, this doesn't look that good. The stock Tesla design has essentially no straight lines in it, so adding that flat chunk of roof makes it look like a hearse. Good concept, mediocre execution.
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Jan 26, 2018 03:41
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Fair enough, it is a very straight line. Something else entirely, 4WD systems: I sort of understand how diffs work and how you can get stuck if for instance both right wheels are spinning. The Tesla has 4WD, but not a locking diff. Would it be possible to use the wheel brakes to slow the spinning wheel and thus transfer traction to the other? With ABS and ~magic computers~, perhaps you can update the Model S software to include a pseudo-locking diff through the wheel brakes to get better 4WD traction in deep snow or sand. It would be very limited compared to a real locking diff of course, but it isn't meant to crawl rocks, just get out of certain situations.
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Jan 26, 2018 11:08
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The other day I asked about Li-ion state of charge vs longevity, and I found an article and chart here.
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Jan 26, 2018 13:34
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angryrobots posted:The other day I asked about Li-ion state of charge vs longevity, and I found an article and chart here. Great article. It mentions an important thing, which is that 100% of cell capacity isn't necessarily as 100% charge on the user display. According to this: https://www.quora.com/How-much-voltage-and-amperage-do-Tesla-battery-packs-have A Tesla pack at 100% is 4.167 volts. If you limit yourself to 90% charge for 90% of your use, you're pretty much in the green area at 85-25. 4000 cycles of 60 kWh at 0.2 kWh/km = 1 200 000 km, with >85% C remaining. I can live with that. Perhaps that's a very ideal scenario. Anyway, my laptop (and my previous) has a charge limiting function, it sits at 55-60% when plugged in. My phone hasn't and might get worse treatment, but 2000 cycles is over 5 years of use. It's going to break from something else before that.
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Jan 26, 2018 14:06
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Ola posted:Fair enough, it is a very straight line. The Model S already has an e-diff (electronic diff) - http://teslaliving.net/2014/08/24/how-does-model-s-traction-control-work/
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Jan 26, 2018 15:49
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Brigdh posted:The Model S already has an e-diff (electronic diff) - http://teslaliving.net/2014/08/24/how-does-model-s-traction-control-work/ quote:Tesla solves this problem by selectively applying the rear brakes to transfer torque to the the non-slipping wheel. So exactly what I suggested...  I had no idea. I've heard of several people getting stuck in snow, but perhaps they had beached themselves.
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Jan 26, 2018 16:02
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Jeeps and other vehicles have had that feature for years. It's not exactly new, but it's still cool.
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Jan 26, 2018 16:51
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kill me now posted:That does look great. But its definitely not a shooting brake, its a wagon, it has 4 doors. Sagebrush posted:I guess I'll go against the grain and say that no, this doesn't look that good. The stock Tesla design has essentially no straight lines in it, so adding that flat chunk of roof makes it look like a hearse. Everybody wins! 
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Jan 26, 2018 17:40
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Ola posted:So exactly what I suggested... No system is fool-proof, and you can't break the laws of physics of course. Now if Tesla had a motor at each corner there would be no need for a differential at all :P
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Jan 26, 2018 17:49
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Charles posted:No system is fool-proof, and you can't break the laws of physics of course. The AMG electric SLS concept did this and the torque vectoring looks amazing. The slow motion shots of the tires being shredded is pretty awesome. To bad they didn't have some snow or ice to mess with. https://www.youtube.com/watch?v=IElqf-FCMs8
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Jan 26, 2018 18:15
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Godholio posted:Jeeps and other vehicles have had that feature for years. It's not exactly new, but it's still cool. Fun fact, the Hummer H1 can actually snap its own axles thanks to this feature. The brakes are inboard, next to the differential rather than out at the hub, which means all braking force is transferred through the halfshafts. Big off road tires are pretty effective flywheels, so if you get one spinning freely at speed and then either hit the brakes or the e-diff decides it's time to get involved you can break something in between.
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Jan 26, 2018 19:01
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Charles posted:Now if Tesla had a motor at each corner there would be no need for a differential at all :P Has any manufacturer yet announced any conclusive plans to produce such a vehicle?
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Jan 27, 2018 00:10
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I thought I knew little about 4WD, but I knew even less. The SLS is an interesting concept, but even though it has four motors, it still has reduction gear, axles, and two CV joints on each axle. I wonder if it's possible, with small enough motors, to integrate the motor in the suspension or have it move with the travel somehow so that the power transfer hardware is reduced, space and weight is saved, but the handling isn't completely ruined. But for city cars, say a VW eUP, Chevy Spark type of thing, they only need around 90 hp and they don't need more than 90 mph top speed. So that's only 20-odd hp per motor with no big need for huge rpms. I guess direct drive might not be very efficient, but with such a small motor, it should be possible to integrate the reduction gear in the unit. Make four equal ones for mass production glory, put one in each corner, no diff, save a bunch of space for batteries, plumbing, cargo or just a smaller car. Great potential for innovation, but nooo it's only self driving and full dash touch panels these days.
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Jan 27, 2018 00:16
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Crazy person drives a Renault Twizy city car (that only has about 35-40 miles range) 526 miles.... takes 4 days. https://www.youtube.com/watch?v=hrzvrcJxe9U
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Jan 27, 2018 00:28
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Three Olives posted:Someone was making the point that the LED headlights don't warm up enough to melt snow, well unless you need to melt snow that is just waste heat. I wonder what costs more in fuel mileage - HIDs that warm themselves enough to melt snow, or headlight wipers and/or squirters. Goober Peas posted:On most modern cars, if drivers would leave their headlight switch in the auto position they'd be fine. I wish it'd be mandated for any car that runs dash illumination at all times (which seems to be most these days) to have automatic headlights, *and* for the switch to be set up so that the default position upon starting the car is auto mode. Give people the ability to switch them off if they really want.
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Jan 27, 2018 00:51
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Ola posted:I thought I knew little about 4WD, but I knew even less. The SLS is an interesting concept, but even though it has four motors, it still has reduction gear, axles, and two CV joints on each axle. I wonder if it's possible, with small enough motors, to integrate the motor in the suspension or have it move with the travel somehow so that the power transfer hardware is reduced, space and weight is saved, but the handling isn't completely ruined. Putting the drive unit in the unsprung portion of the suspension sucks, and when you move it inboard to the sprung weight, you end up with... CV joints, and a very strong production incentive to go with a single motor and a differential.  The performance benefits just aren’t large enough to justify the complexity of individual drive motors. At least not for a passenger car expected to do 90mph.
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Jan 27, 2018 00:53
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MrYenko posted:Putting the drive unit in the unsprung portion of the suspension sucks, and when you move it inboard to the sprung weight, you end up with... CV joints, and a very strong production incentive to go with a single motor and a differential. You're right, I'm sure. Maybe all EV manufacturers play with this idea on day 1, before it becomes obvious. Another config thing with EVs is low profile RWD, like the Smart ForTwo and similar. Doesn't build much in the vertical, so you don't lose trunk space and no drive shaft obviously. But it also means the front wheels are unencumbered by drive gear and can be built with more steering angle to get a much better turning circle, which is sweet in town.
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Jan 27, 2018 01:23
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Ola posted:You're right, I'm sure. Maybe all EV manufacturers play with this idea on day 1, before it becomes obvious. Another config thing with EVs is low profile RWD, like the Smart ForTwo and similar. Doesn't build much in the vertical, so you don't lose trunk space and no drive shaft obviously. But it also means the front wheels are unencumbered by drive gear and can be built with more steering angle to get a much better turning circle, which is sweet in town. Cf. ZF’s 75-degree steering front suspension design.
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Jan 27, 2018 04:56
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Haven't read the white paper yet, but maybe unsprung motors aren't totally stupid? http://www.proteanelectric.com/heresy-unsprung-lotus-engineering-unsprung-weight-doesnt-really-matter-muchthe-truth/ The name of the URL is misleading, it does matter... Perhaps motors like this could augment a 2wd ev.
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Jan 27, 2018 08:42
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Yeah, that's sort of what I was thinking. Particularly on smaller cars, there has to be a limit within which it's fine. A scooter is fine, even though it has the entire gearbox unsprung. I've been chanting unsprung weight every time hub motors are mentioned as well, but how bad can it be? Many big cars today have excellent handling even though their wheels and brakes weigh an absolute fuckton.
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Jan 27, 2018 09:05
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