Pray tell, then, how is a "proper university diploma" any better if the trade schools do the job right (assuming they do)? Except that you find the name or concept of a "proper university diploma" somewhat more appealing?
Heck, in fact I think it'd be an interesting challenge to offer tradesman services via remotely-operated robots. "Hey, we've got a bunch of electricians out of work in State X, let's have them do something useful in State Y where a recent Hurricane sent the trades' rates and waiting periods soaring". Hmmm.
Oh, so the "state" people from Minnesota can't read for themselves and need a face-to-face chat like you'd have with natives in some backwards place. Point taken, thank you.
Even without moving the connector locations, the harness issue is solvable by preassembling it on a jig, and then transferring the whole subassembly -- all you need is a custom vacuum sucker nozzle to hold everything in place while it's being moved. Such nozzles can be done entirely on a machine: 3D printer for the plastic body, and then a bead machine to deposit a silicone bead.
Somewhat? The same version stuck for more than a year IIRC. It's as good as a dead project from user viewpoint. No updates for a couple months in a project of such scale and you have every reason to worry.
modern vehicles have two independent hydraulic systems going to the calipers
LOL, you're making shit up. Even very safety concious car makers like Volvo don't do that, and IIRC never did! Older Volvos used to have independent front and rear brake circuits IIRC, and there was an isolation valve so that should one of them produce more flow than the other, the high flow one would be cut off and the other one would still be operational. When this valve tripped, the BRAKE idiot light would illuminate. I don't recall two brake lines going to calipers even there!
On a modern car, the brake circuits are individual between the brake control module (a.k.a. ABS module) and the calipers, but there is just a single brake line going to each caliper! There is no mecahnism implemented that would detect a leak in an individual brake line and plug it. There are actuators to do just that, but there are no flow sensors, and in case of typical pinhole leaks, the brake pressure is only lost when you are out of brake fluid, so merely sensing circuit pressure wouldn't help you.
I have had a pinhole leak in a brake line in a 2000 Volvo, and sure as heck it'd leave you without hydraulic brakes. A friend of mine had the same on a nice 2004 BMW, with same outcome. You're really talking out of your ass, and you well know it. Someone please moderate the parent as a troll, because he sure as heck deserves it!
That's not very accurate at all. You sort of get the idea, but are not sure at all how it really works.
Think of a balance of forces on a small segment of a tire. Air pressure is merely applied from the inside of the tire. If that's all there was, the tire would explode: after all, the forces have to be balanced and you don't have anything keeping the tire material from being pushed outwards by the air. If your tire is a balloon of sorts, very floppy, the air pressure will be counteracted by any external contact pressure, and by the hoop stresses in the tire material (the rubber!). So the stress in the rubber most definitely has to counteract all of the air pressure, except when there's external load on the tire! This holds true whether the tire is floppy or not, only that stresses other than hoop stresses and contact stresses come into play.
What you mean by "the rubber carries the remaining weight" is, in reality, the fact that the tire not only carries the normal stresses, but also shear stresses. And it's not only the rubber doing that, there are polyester and steel wires (usually) helping out! When you add shear stresses into the mix, then you can deviate from the constant contact patch pressure. A modern good car tire has, IIRC, about 40 rubber components of various properties, so it's not just a monolithic cast rubber chunk with some wires inside!
Your claim that "setting n to be large" is pretty much meaningless, there's no such "n" in any sort of tire engineering. You could use it for some sort of a pretend "advanced" tire model that's only fit to use in grade school. If you want to go that far, I'd much rather introduce the conept of free body diagram (if not already done) and shear and normal stresses, and use that to realistically show what happens in a tire. Your point of view is pretentious in that it seems to be quantitative, but the quantity doesn't describe any behavior at all.
You could, perhaps, argue that "n" is the ratio of shear-to-normal stress, but then you have to be explicit as to where in the tire it's checked, under what conditions, and what shear and normal stresses are talked about (there are several you can choose from!) -- so again, not a useful figure the way you describe it, and not a figure that's used in any sort of engineering!
Agreed somewhat. The assumption of contact patch area having a constant pressure is pretty much a grade-school kind of approximation. No street tire acts that way -- there's this pesky fact that pressure across the contact patch is not constant unless you're riding on a balloon. Real life tires carry significant shear stresses that allow them to produce a rather interesting non-constant pressure distribution across the patch. See my other post.
Yeah, but you see, in a constant pressure approximation like you claim, the tire is a balloon where surface is assumed not to carry any shear stress -- otherwise the pressure won't be constant across the contact patch area. Thus if you merely place such an imaginary tire on the snow, the pressure on the snow is determined by tire pressure. Nothing more, nothing less. But go ahead and test it on balloon-like-tires: smooth-ish wide bicycle tires are perfect for such a test. Rolling across your finger with 15psi in the tire is much more pleasant than with 30psi in the tire. On my wife's car, I merely squirm if she rolls over my foot with the front tire deflated to 15psi (I tested it before writing the answer, mind you).
Since car tires are not really shear-free balloons, the constant pressure approximation doesn't hold, and pressure is maximal in the middle of the patch, in absence of rolling. The ratio of maximum to average pressure depends on the circumferential length of the patch. Narrower tires produce a higher pressure peak in the middle since their contact patch is longer in circumference, having been forced to be narrower in lateral direction. Apparently that works better on the snow, but your "pressure = force x area" exclamation doesn't matter here, and grade school science usually doesn't talk much about pressure distributions in tires. You need to know a bit of mechanics of materials to understand what shear stress is and how a ballon-model-vs-tire differ in that respect. That's some very nice grade school you went to if they taught you that!
Because, obviously, the wheels know they are subject to magical breaking torque from the engine, rather than ordinary braking torque from brakes, huh? If you did never lock up your drive wheels using engine braking, you haven't tried hard enough. Brakes are usually quite accurate and you can apply very minute braking pressures -- say decreasing your air-drag-and-rolling-friction-only (no feet on the pedals) braking distance by half. That means that it's quite feasible to apply only as much extra braking torque as is effectively provided by rolling friction and air drag alone. I wouldn't call it "light pressure on the brakes can be enough to lock the wheels". I can brake just fine on smooth ice without the ABS kicking in, if I want to.
Care to explain how reducing engine torque (usually by cutting fuel supply) when the wheels lose traction causes accidents? Because that's what your cop buddy doesn't seemingly realize is all that traction control does. I think your buddy is just confused as hell, that's what I think, and you trust his confused self.
Some people say the air bag and seat belt work in sync, they do not. Modern air bags deploy so fast its already halfway inflated by the time the locking mechanism in your seat belt kicks in.
I don't know where you live and what you consider modern, but an otherwise pitiful '00 Volvo S40 has pyrotechnic seat belt tensionsers controlled by the SRS control module. That's a 12 year old model. That makes your statement 12 years behind the times, at least. The mechanical locking mechanism in the seat belt spool is pretty much there for use when braking without impact, and as a backup in case the SRS system is inoperative.
I think you have no clue how stability augmentation actually works. Stability augmentation not only provides additional steering torque from asymmetric braking, but will also control weight transfer between the wheels to maintain sufficient traction on all four wheels. It does it an order of magnitude faster than any human could do it in feedback control (i.e. without pretraining). With pretraining, a human is able to apply feedforward control -- i.e. brake inputs that are anticipatory in nature. Such feedforward control is only available periodically when you're paying full attention. I'm sure as heck drivers on a racetrack can be quite spent after just a few laps. Now imagine having to do an 8 hour stretch that way, ha ha. Alas, stability augmentation is always there, never tired, never bored, never distracted. Yet the control inputs available to the human are very crude: only one brake pedal. The stability augmentation system has individual control of all four brakes. With such understanding, perhaps you'd be able to get it into your head that a stability-augmented race car would not only make you safer, it'd give you very clear advantage over dolts who insist it's bad for them. The uninformed arguments against stability augmentation are eerily like from those, 80 years ago, who were against electric lights. In retrospect it makes you look very, very silly.
You're mixing up traction control with stability augmentation, unless you were really accelerating on that roundabout. Traction control limits engine torque applied to the wheels when said wheels lose traction. Stability augmentation uses individual control of brakes to provide steering torques that are not available from steering system alone. This is what most dolts out there fail to get, and I get really upset about it. On a classic car there is no lever to actuate to provide steering torques using the brakes -- yet applying such, based on your steering wheel inputs, is precisely what stability augmentation does! Asymmetric braking can provide you with very nice steering torques that can exceed whatever you get from turning the front wheels alone. Arguing that it's a bad thing to have this capability is going full retard. There are no asymmetric braking controls on stock cars without stability augmentation. With stability augmentation your steering wheel inputs, in certain conditions, are used to apply just such asymmetric braking. This works in concert with ABS sensors to ensure that wheels don't lock up and all available traction is used up for steering purposes. About the only thing you'd need in a sports car is aural indication of how much augmentation is applied. This would have let you figure out in real time how much margins you have left before you'll lose control.
You're silly. Traction control is inactive when you're not applying throttle. If you're hitting ice with throttle down and get the wheels to spin, well, traction control will try its best to limit engine power (and perhaps apply brakes to slow down spinning wheels on models with active brake pump modules).
Nope, not Galileo:) I meant Huygens/Cassini -- you have to be really, really stupid to throw away one-of-a-kind data on frame sync errors. That's what would have killed Huygens data return -- otherwise, even with cycle slips, the data could be reconstructed on the ground without much trouble. The SSDs are doing the same thing: sure, when wear limits are passed and there's plenty of read errors, you can't relocate failing blocks to save them, but don't pretend that you know better than the owner of the data. Effectively killing the whole drive just because write endurance is up is even worse than the frame dropping on Cassini's probe support avionics. It's like turning off the entire receiver simply because there were some errors.
Don't be obtuse. The scaling of lifetime in proportion to ratio of allocated to available memory -- duh, I'm not talking about that! What I'm talking about is that the drive firmware makes the drive as a whole give up the ghost as soon as the write endurance is used up. There's no first principles behind that other than someone's stupidity (even if it's institutional stupidity). Unfortunately, going full retard like that (throwing out all of the data because a tiny bit of it might be bad and some functionality is lost) also seems to find its way into space missions, occasionally. I invite you to guess which one I'm talking about:)
The machinery can be reusable across models, there'd be specialized conveyor and end effector tooling. A lot of that can be done quickly using 3D printers. Times are changing.
By properly engineering the design process, those purpose build machines would be co-designed with other parts, it's a matter of what you're familiar with. Apple has been designing on purpose for manual assembly. It'd be, internally, quite a different product if it was meant for automated assembly. iPhone could be put together using rather simple machinery. All you need is a computer-assisted design-for-manufacturing process where when a part design is finalized, you also have finalized end effectors, conveyor tooling and motion specs. No need to be dumb about it.
It doesn't need to be assembled largely by hand. It's purposely designed to be assembled by hand, since that's what you do when you have Chinese labor available in a Foxconn factory. Much less set up cost than automation, and initially faster adaptability to demand as well. If you wanted an automated assembly line, then it'd make just as much sense to make it in the U.S. or Europe, and it'd be designed for such an automated assembly process.
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Pray tell, then, how is a "proper university diploma" any better if the trade schools do the job right (assuming they do)? Except that you find the name or concept of a "proper university diploma" somewhat more appealing?
Heck, in fact I think it'd be an interesting challenge to offer tradesman services via remotely-operated robots. "Hey, we've got a bunch of electricians out of work in State X, let's have them do something useful in State Y where a recent Hurricane sent the trades' rates and waiting periods soaring". Hmmm.
Gym classes are fairly useless when it comes to keeping you fit, or burning off lots of excess calories. Unless you'd have one 365 days a year.
Oh, so the "state" people from Minnesota can't read for themselves and need a face-to-face chat like you'd have with natives in some backwards place. Point taken, thank you.
Even without moving the connector locations, the harness issue is solvable by preassembling it on a jig, and then transferring the whole subassembly -- all you need is a custom vacuum sucker nozzle to hold everything in place while it's being moved. Such nozzles can be done entirely on a machine: 3D printer for the plastic body, and then a bead machine to deposit a silicone bead.
Somewhat? The same version stuck for more than a year IIRC. It's as good as a dead project from user viewpoint. No updates for a couple months in a project of such scale and you have every reason to worry.
modern vehicles have two independent hydraulic systems going to the calipers
LOL, you're making shit up. Even very safety concious car makers like Volvo don't do that, and IIRC never did! Older Volvos used to have independent front and rear brake circuits IIRC, and there was an isolation valve so that should one of them produce more flow than the other, the high flow one would be cut off and the other one would still be operational. When this valve tripped, the BRAKE idiot light would illuminate. I don't recall two brake lines going to calipers even there!
On a modern car, the brake circuits are individual between the brake control module (a.k.a. ABS module) and the calipers, but there is just a single brake line going to each caliper! There is no mecahnism implemented that would detect a leak in an individual brake line and plug it. There are actuators to do just that, but there are no flow sensors, and in case of typical pinhole leaks, the brake pressure is only lost when you are out of brake fluid, so merely sensing circuit pressure wouldn't help you.
I have had a pinhole leak in a brake line in a 2000 Volvo, and sure as heck it'd leave you without hydraulic brakes. A friend of mine had the same on a nice 2004 BMW, with same outcome. You're really talking out of your ass, and you well know it. Someone please moderate the parent as a troll, because he sure as heck deserves it!
Electric lights are dangerous and a bad idea. Gas lights are dangerous and a bad idea. You get the drift of that, I'm sure. Informative, my ass.
That's not very accurate at all. You sort of get the idea, but are not sure at all how it really works.
Think of a balance of forces on a small segment of a tire. Air pressure is merely applied from the inside of the tire. If that's all there was, the tire would explode: after all, the forces have to be balanced and you don't have anything keeping the tire material from being pushed outwards by the air. If your tire is a balloon of sorts, very floppy, the air pressure will be counteracted by any external contact pressure, and by the hoop stresses in the tire material (the rubber!). So the stress in the rubber most definitely has to counteract all of the air pressure, except when there's external load on the tire! This holds true whether the tire is floppy or not, only that stresses other than hoop stresses and contact stresses come into play.
What you mean by "the rubber carries the remaining weight" is, in reality, the fact that the tire not only carries the normal stresses, but also shear stresses. And it's not only the rubber doing that, there are polyester and steel wires (usually) helping out! When you add shear stresses into the mix, then you can deviate from the constant contact patch pressure. A modern good car tire has, IIRC, about 40 rubber components of various properties, so it's not just a monolithic cast rubber chunk with some wires inside!
Your claim that "setting n to be large" is pretty much meaningless, there's no such "n" in any sort of tire engineering. You could use it for some sort of a pretend "advanced" tire model that's only fit to use in grade school. If you want to go that far, I'd much rather introduce the conept of free body diagram (if not already done) and shear and normal stresses, and use that to realistically show what happens in a tire. Your point of view is pretentious in that it seems to be quantitative, but the quantity doesn't describe any behavior at all.
You could, perhaps, argue that "n" is the ratio of shear-to-normal stress, but then you have to be explicit as to where in the tire it's checked, under what conditions, and what shear and normal stresses are talked about (there are several you can choose from!) -- so again, not a useful figure the way you describe it, and not a figure that's used in any sort of engineering!
Agreed somewhat. The assumption of contact patch area having a constant pressure is pretty much a grade-school kind of approximation. No street tire acts that way -- there's this pesky fact that pressure across the contact patch is not constant unless you're riding on a balloon. Real life tires carry significant shear stresses that allow them to produce a rather interesting non-constant pressure distribution across the patch. See my other post.
Yeah, but you see, in a constant pressure approximation like you claim, the tire is a balloon where surface is assumed not to carry any shear stress -- otherwise the pressure won't be constant across the contact patch area. Thus if you merely place such an imaginary tire on the snow, the pressure on the snow is determined by tire pressure. Nothing more, nothing less. But go ahead and test it on balloon-like-tires: smooth-ish wide bicycle tires are perfect for such a test. Rolling across your finger with 15psi in the tire is much more pleasant than with 30psi in the tire. On my wife's car, I merely squirm if she rolls over my foot with the front tire deflated to 15psi (I tested it before writing the answer, mind you).
Since car tires are not really shear-free balloons, the constant pressure approximation doesn't hold, and pressure is maximal in the middle of the patch, in absence of rolling. The ratio of maximum to average pressure depends on the circumferential length of the patch. Narrower tires produce a higher pressure peak in the middle since their contact patch is longer in circumference, having been forced to be narrower in lateral direction. Apparently that works better on the snow, but your "pressure = force x area" exclamation doesn't matter here, and grade school science usually doesn't talk much about pressure distributions in tires. You need to know a bit of mechanics of materials to understand what shear stress is and how a ballon-model-vs-tire differ in that respect. That's some very nice grade school you went to if they taught you that!
Because, obviously, the wheels know they are subject to magical breaking torque from the engine, rather than ordinary braking torque from brakes, huh? If you did never lock up your drive wheels using engine braking, you haven't tried hard enough. Brakes are usually quite accurate and you can apply very minute braking pressures -- say decreasing your air-drag-and-rolling-friction-only (no feet on the pedals) braking distance by half. That means that it's quite feasible to apply only as much extra braking torque as is effectively provided by rolling friction and air drag alone. I wouldn't call it "light pressure on the brakes can be enough to lock the wheels". I can brake just fine on smooth ice without the ABS kicking in, if I want to.
People routinely confuse traction control with stability augmentation (a.k.a. ESC).
Care to explain how reducing engine torque (usually by cutting fuel supply) when the wheels lose traction causes accidents? Because that's what your cop buddy doesn't seemingly realize is all that traction control does. I think your buddy is just confused as hell, that's what I think, and you trust his confused self.
Some people say the air bag and seat belt work in sync, they do not. Modern air bags deploy so fast its already halfway inflated by the time the locking mechanism in your seat belt kicks in.
I don't know where you live and what you consider modern, but an otherwise pitiful '00 Volvo S40 has pyrotechnic seat belt tensionsers controlled by the SRS control module. That's a 12 year old model. That makes your statement 12 years behind the times, at least. The mechanical locking mechanism in the seat belt spool is pretty much there for use when braking without impact, and as a backup in case the SRS system is inoperative.
I think you have no clue how stability augmentation actually works. Stability augmentation not only provides additional steering torque from asymmetric braking, but will also control weight transfer between the wheels to maintain sufficient traction on all four wheels. It does it an order of magnitude faster than any human could do it in feedback control (i.e. without pretraining). With pretraining, a human is able to apply feedforward control -- i.e. brake inputs that are anticipatory in nature. Such feedforward control is only available periodically when you're paying full attention. I'm sure as heck drivers on a racetrack can be quite spent after just a few laps. Now imagine having to do an 8 hour stretch that way, ha ha. Alas, stability augmentation is always there, never tired, never bored, never distracted. Yet the control inputs available to the human are very crude: only one brake pedal. The stability augmentation system has individual control of all four brakes. With such understanding, perhaps you'd be able to get it into your head that a stability-augmented race car would not only make you safer, it'd give you very clear advantage over dolts who insist it's bad for them. The uninformed arguments against stability augmentation are eerily like from those, 80 years ago, who were against electric lights. In retrospect it makes you look very, very silly.
You're mixing up traction control with stability augmentation, unless you were really accelerating on that roundabout. Traction control limits engine torque applied to the wheels when said wheels lose traction. Stability augmentation uses individual control of brakes to provide steering torques that are not available from steering system alone. This is what most dolts out there fail to get, and I get really upset about it. On a classic car there is no lever to actuate to provide steering torques using the brakes -- yet applying such, based on your steering wheel inputs, is precisely what stability augmentation does! Asymmetric braking can provide you with very nice steering torques that can exceed whatever you get from turning the front wheels alone. Arguing that it's a bad thing to have this capability is going full retard. There are no asymmetric braking controls on stock cars without stability augmentation. With stability augmentation your steering wheel inputs, in certain conditions, are used to apply just such asymmetric braking. This works in concert with ABS sensors to ensure that wheels don't lock up and all available traction is used up for steering purposes. About the only thing you'd need in a sports car is aural indication of how much augmentation is applied. This would have let you figure out in real time how much margins you have left before you'll lose control.
You're silly. Traction control is inactive when you're not applying throttle. If you're hitting ice with throttle down and get the wheels to spin, well, traction control will try its best to limit engine power (and perhaps apply brakes to slow down spinning wheels on models with active brake pump modules).
Probably, the best all-round solution would be to go read-only, "Oh Pharaoh! forgive me but I need more Nu-Papyrus!!"
Whooosh. No kidding! Really?! No shit Sherlock.
Nope, not Galileo :) I meant Huygens/Cassini -- you have to be really, really stupid to throw away one-of-a-kind data on frame sync errors. That's what would have killed Huygens data return -- otherwise, even with cycle slips, the data could be reconstructed on the ground without much trouble. The SSDs are doing the same thing: sure, when wear limits are passed and there's plenty of read errors, you can't relocate failing blocks to save them, but don't pretend that you know better than the owner of the data. Effectively killing the whole drive just because write endurance is up is even worse than the frame dropping on Cassini's probe support avionics. It's like turning off the entire receiver simply because there were some errors.
Don't be obtuse. The scaling of lifetime in proportion to ratio of allocated to available memory -- duh, I'm not talking about that! What I'm talking about is that the drive firmware makes the drive as a whole give up the ghost as soon as the write endurance is used up. There's no first principles behind that other than someone's stupidity (even if it's institutional stupidity). Unfortunately, going full retard like that (throwing out all of the data because a tiny bit of it might be bad and some functionality is lost) also seems to find its way into space missions, occasionally. I invite you to guess which one I'm talking about :)
The machinery can be reusable across models, there'd be specialized conveyor and end effector tooling. A lot of that can be done quickly using 3D printers. Times are changing.
By properly engineering the design process, those purpose build machines would be co-designed with other parts, it's a matter of what you're familiar with. Apple has been designing on purpose for manual assembly. It'd be, internally, quite a different product if it was meant for automated assembly. iPhone could be put together using rather simple machinery. All you need is a computer-assisted design-for-manufacturing process where when a part design is finalized, you also have finalized end effectors, conveyor tooling and motion specs. No need to be dumb about it.
It doesn't need to be assembled largely by hand. It's purposely designed to be assembled by hand, since that's what you do when you have Chinese labor available in a Foxconn factory. Much less set up cost than automation, and initially faster adaptability to demand as well. If you wanted an automated assembly line, then it'd make just as much sense to make it in the U.S. or Europe, and it'd be designed for such an automated assembly process.
huh? Looks to me like it has at least two dozen screws ;)