how hard can it be to not run over large objects?

The fingers said:
gogo said:
dogman said:
Just try to use the 2 second rule in LA. If you do, two cars slot into the huge space you tried to leave in front of you.
Same in Phoenix, but you forgot to mention the tailgaters. Heck, right here in my 21 sq. mi. 'city' there is one awkward highway entrance area where, moments after discussing its hazard with my passenger, 5 cars rear-ended each other directly behind me (bam-bam-bam-bam-thunk).
I leave a huge space in front of me anyway, like I'm hauling 40 tons of steel. I'd rather see or hear the carnage behind me, and just watch the parade of fools wizz by. :twisted:
I do too, but one can't then ignore the threat of whiplash type injury from getting hit from behind when choosing the lesser of the evils. Sometimes its the better choice to proceed over the large object than be hit from behind. (Large object never being a human, if that's what dnmun was assuming)
 
dogman said:
Tesla simply realizes that shit happens. You can be following at a safe distance for normal driving, and still hit shit because it fell off the truck in front of you, or you just never had time to see it till the vehicle ahead ran over it also. And of course, harder to see such things at night till you are closer to them.

I've driven over ladders, pallets, and loose 2x4's. I've had very near misses of crap spit out of the wheels in the lane next to me, so suddenly a tire, a 2x4 or what have you is bouncing into your lane. I'm not that dumb, that I'm going to jerk the wheel at 75 mph. That's how you go over the barriers upside down. Hell yeah you swerve, but not too fast or too far for that speed.

If you are driving the open road, without being surrounded by semi trucks, then you can easily see and avoid. But you don't get to drive like that much on I-10.

If on city streets, speeds of 45 mph or less, then of course it's quite easy to not run over a ladder. But on the freeway, even following using the two second rule, you won't have much time to avoid any object that covers your entire lane.

Just try to use the 2 second rule in LA. If you do, two cars slot into the huge space you tried to leave in front of you.

i am just amazed that people do not have control over their car. maybe they are big hulking tons of steel with no steering input but i have never had any trouble driving around stuff on the highway so when people tell me they are trained to run over it and not leave their mentally restricted path directly ahead, it just makes me sick. but then seeing people waste their lives on video games does the same thing. but i know one in four on the highway are looking at their phones. if you don't notice that, you aren't looking at that either. how can you not know the other cars around you when you have mirrors and eyes. and why would they not move over if you pushed into their lane?

and yes, i do stop on the freeway and pick up ladders. that is how i got a 10' stepladder after it backed up traffic on I25 north of denver for 4 miles. i was the only person to stop and throw it in the back of my pickup.

another time driving into north denver, 4 lanes wide and it is backed up 6 miles because some poor woman is dead in the middle lane. so i pulled immediately in front of her, backed up to her car and since i had no rope all i could use was a comealong i had laying in the bed of the truck. so i pulled some slack out on the comealong and hooked her bumper on my bumper and i had a to actually tell her to put the car, actually another huge van, into neutral since she had no clue, and to release the parking brake. amazing how difficult it is for people to function.

so i was trying to pull her over to the shoulder to clear traffic, but the jerks kept trying to pass on the right and did not wanna give an inch so i could move her off the roadway. people in cars are desperate sick demented selfish oafs. and now i find out they are trained to run over stuff rather than avoid it. i am just too old for this new world of ignoranti.
 
dnmun said:
… i am just too old for this new world of ignoranti. …
Much is not detailed in forum posts, and I must believe what you reference, or are thinking about, is different than what I and others are. Evasive maneuvers can lead to dynamic instability which then causes that driver's actions and their vehicle to be a bigger problem than would have been the case if they had run over the object. You've oviously had physics classes and years of driving experience, so I it seems odd that you don't want to recognize the point.

Even if you are arguing that physics dictates that one drive so slow as to be able to react to the .01% possibility, you still have to protect yourself from getting rear-ended. I agree in general though, dnmun, that our culture of speed and haste on roadways is beyond ridiculous. The traffic is the major reason I don't live in Phoenix anymore.
 
no, i mean 70mph is not so fast that you lose the ability to control the car. and no, i flunked outa sophomore physics so i never took it. i just started physics with grad school courses in E&M, mechanics and thermodynamics. i only learned any physics when i had to teach it. learned to drive in 1956 chevy on two lane roads in rural mississippi. the reason i was taught how to drive off the road without losing control is because there is a high risk of head on collisions on rural two lane roads and my dad wanted me to know how to avoid them. obviously your dad did not teach you that. of course for me it was in 1960, not 2010 as it is for you.
 
dnmun said:
no, i mean 70mph is not so fast that you lose the ability to control the car. and no, i flunked outa sophomore physics so i never took it. i just started physics with grad school courses in E&M, mechanics and thermodynamics. i only learned any physics when i had to teach it. learned to drive in 1956 chevy on two lane roads in rural mississippi. the reason i was taught how to drive off the road without losing control is because there is a high risk of head on collisions on rural two lane roads and my dad wanted me to know how to avoid them. obviously your dad did not teach you that. of course for me it was in 1960, not 2010 as it is for you.

I took my driver's test in a 1956 Buick. I'll take all that as a disclaimer that you are resistant to understanding vehicular dynamics. Driving off the road is 'ditching' and is a last resort manuver in which you lose a great deal of control and risk personal injury. I'll run over animals before incurring the risk of personal injury that comes with ditching, so I guess we can agree to disagree about that category.

I think we may still agree, however, that people don't seem to take the responsibility for the path of their potentially deadly weapon seriously enough.
 
Did I say that I can NEVER swerve around something at 70 mph? Obviously if you have space in front of you, you can see it in time, and have time to honk, then start crowding that car beside you. We have all missed shit in the road, but maybe not every time. But other times you don't have time for anything. Like when a truck sheds it's recap right in front of you.

I "ditched" a minivan at 75mph once when surrounded by semi trucks that crowded me off the left lane. I did not crash, or lose control of the car. Yes, I can also drive. I was lucky though, there was a ditch. In some highway situations, the "ditch" is not more that 2' wide. Bridges for example.

Tesla realizes that situations arise, particularly in very crowded city highway, where you simply cannot swerve around that stupid ladder in the road. So you do run over it, when the alternative is ducking under the trailer of a moving 18 wheeler. Once that stupid ladder has fallen off on the overpass of the spaghetti bowl interchange, it's 12 feet long, and the space you have to swerve is 2 feet. Ok, so you stop in the freeway? Or run that thing over? I'd rather run it over than have that 18 wheeler that's tailgating me while the driver watches porn on his phone hit me from behind.
 
Every week when I read the paper there are a number of rollover and other accidents related to people trying to miss animals, usually deer (I live in rural Maine.) I never swerve to miss an animal, hammer the brakes - yes, but swerve, no. When you have well constructed roads with no boulders or trees 5 feet from the edge of the road then you might have a chance but many of the roads around here are paved over trails, that is, there is no room for error. The consequences are simply too great if something goes awry.
 
I ran over two kegs of beer that fell off a budweiser truck, ditch on the right and heavy traffic to the left.
luckily I was driving a large truck myself. Shit happens
 
Chalo said:
dnmun said:
it is nauseating to read all this stuff about how you cannot stop or avoid running over animals or people in the roadway. if you cannot avoid objects in the roadway even when driving 70 mph then you need to not drive.

What he said. If you are driving too fast to react safely to things that appear in your path, you're simply driving too fast, or not paying attention to the task at hand. Just because driving unsafely is pervasive does not make it OK.

I hope I live to see car-free central city areas, and blanket 20mph speed limits for cars elsewhere within city limits. We need to take our lives and our cities back from the murder machines.


Have you actually seen a road before?

At 70mph it takes 100 meters to stop. 70mph roads can have long grass verges a few meters from the roadside. An animal can be out of the grass and on to the carriageway in a flash. So fast I shouldn't have to calculate it for you. At the minimum allowable carriageway speeds you don't have the braking distance required to stop for an animal tearing out from the grass verge. Your living in the land of make believe, probably with a large que behind you, waiting to get a ticket.
 
friendly1uk said:
Chalo said:
dnmun said:
it is nauseating to read all this stuff about how you cannot stop or avoid running over animals or people in the roadway. if you cannot avoid objects in the roadway even when driving 70 mph then you need to not drive.

What he said. If you are driving too fast to react safely to things that appear in your path, you're simply driving too fast, or not paying attention to the task at hand. Just because driving unsafely is pervasive does not make it OK.

I hope I live to see car-free central city areas, and blanket 20mph speed limits for cars elsewhere within city limits. We need to take our lives and our cities back from the murder machines.


Have you actually seen a road before?

At 70mph it takes 100 meters to stop. 70mph roads can have long grass verges a few meters from the roadside. An animal can be out of the grass and on to the carriageway in a flash. So fast I shouldn't have to calculate it for you. At the minimum allowable carriageway speeds you don't have the braking distance required to stop for an animal tearing out from the grass verge. Your living in the land of make believe, probably with a large que behind you, waiting to get a ticket.


And that's just the physics of it. Throw into the mix: recognition/reaction times for humans and it will take longer.
 
cal3thousand said:
friendly1uk said:
Chalo said:
What he said. If you are driving too fast to react safely to things that appear in your path, you're simply driving too fast, or not paying attention to the task at hand. Just because driving unsafely is pervasive does not make it OK.

I hope I live to see car-free central city areas, and blanket 20mph speed limits for cars elsewhere within city limits. We need to take our lives and our cities back from the murder machines.


Have you actually seen a road before?

At 70mph it takes 100 meters to stop. 70mph roads can have long grass verges a few meters from the roadside. An animal can be out of the grass and on to the carriageway in a flash. So fast I shouldn't have to calculate it for you. At the minimum allowable carriageway speeds you don't have the braking distance required to stop for an animal tearing out from the grass verge. Your living in the land of make believe, probably with a large que behind you, waiting to get a ticket.


And that's just the physics of it. Throw into the mix: recognition/reaction times for humans and it will take longer.

And this "recognition/reaction times for humans" can have huge variations. There is no test or limit to get a driverlicens... sad

braking distance is : recognition-reaction-brakepedalmovement-physical.stop.distance

Additional there are also people allowed to driving with only 1 eye or with 1 leg or epileptic...... becouse freedom and so... :p
 
I agree that an animal darting from cover at the roadside is very difficult to avoid when travelling at speed.

However the braking distances quoted are badly out-dated. Cars of 10-15 years ago could stop from 70mph in 40-50m and things have gotten better.

Reaction time can be greatly reduced by anticipation :)
 
I was driving along one evening, when a deer ran out from the woody area next to the road, into the road. It was far away enough that I was able to stop without hitting it. Whew! Then I carried on driving as the deer disappeared into the vegetation on the other side of the road.

The deer then waited until I was level with it, and leaped back into the road, and I hit it. Fortunately, I wasn't going very fast at that point, so it wasn't killed.

Some things you just can't anticipate.
 
Yeah, I've dodged deer, elk, and one time missed a horse size orynx by a hair. They have those gigantic African antelopes on the missile range. That one was particularly close. In a truck loaded top heavy with a hot air balloon and six people, I could have rolled it easy. Everybody in the truck just went OMG, and then started telling me I drive as good as I fly.

You gotta see it, then decide which way to swerve, then swerve but not roll it. All in very little time. What will flip your car is when you stand on the brakes and swerve. I generally try to swerve without hitting the brakes, you need to have good traction to swerve. You can do a pretty quick lane change at speed. Look at a nascar race. But on a busy highway, you may have a semi in that lane next to you, and he might be keeping one wheel on the paint stripe. If you are following large vehicles, you don't see what fell off a vehicle earlier till it's flipping at your windshield. You try to leave some space, but sometimes there simply isn't space. I-10 in my area, at certain times of day it will look more like a train track than a highway. That many trucks headed to LA.
 
This is one thing I like about driving a car rather than a 4x4/SUV. The car's lower centre of mass means that it is almost impossible to roll by swerving. Yes you can spin out if you overdo things, but at least you don't end up on your head :) Unless you're sliding sideways and the leading wheels hit a kerb or dig into soft ground...
 
Not entirely impossible. I once saw a sports car driving crazy, swerving around everybody doing 100. Three miles later there he was, upside down. But yeah, at 70 he would have been unlikely to flip. My guess is, he did strike one of those large objects going 70 mph he was swerving around. Half a mile farther on, an 18 wheeler was parked on the side of the road. Lucky dude, he was standing there staring at his beautiful car upside down.

After years of driving more poor handling vehicles, trucks, minivans, etc, I sure like my Subaru forester now. The all wheel drive gives me a much better chance of missing anything I need to swerve around. It's not all jacked up like a big V8 suv that's basically just a truck. So it handles pretty much like a car, but with all wheel grip. Nice in the wet, when we get some.

It doesn't hurt any that the Subaru is now being driven like an old fart hypermiler. I'm not driving to the balloon rally at 80 mph anymore at 4 am. Just going to town, at 60 mph, after the morning rush hour backs off. Never late and rushing when you retire.
 
This article explains nicely why vehicles with a high centre of mass tend to rollover:

http://www.ehow.com/info_12155124_cars-roll-over.html

I didn't realise there was a snapping point where they suddenly flip without warning, but thinking back to footage I've seen in the past it makes sense.
 
My oldest brother flipped a Porsche 911 at 25-30 mph. Then he flipped his wife's old Beetle at probably less speed. All before I'd learned to drive. He made comments about me, to which I said "Excuse me, but not only have I NEVER wrecked a car, I'd have to wreck a LOT of them to catch up to you." Peace at last.

We could get a whole thread going on just two words. 'Roll center.' Which can be below the ground. Ya gotta be careful reading ehow, they carry on about things they don't even know anyhow. NEVER put polyester resin right on eps foam to make a surfboard.
 
The older bugs could be flipped easy. You just jab the brakes in the right part of a corner, load that rear swingarm, and the result was much like bouncing off a diving board. The proper technique with those old bugs with the one piece axles was to jab the gas in the corners. You might be braking to the last second, but get off em as soon as you feel that rear end loading up. Then gas it. Corvairs would flip the same way, for the same reason. That 911, if it was old enough may have had the same one piece axle. The kind with just one axle boot. Later bugs in the 70's came out with an axle more like a modern one, with a CV on the end, and two axle boots. This made them less flip prone if you brake in a corner. But a bug is still a fairly tall vehicle compared to modern cars. We used to joke they made em so round so they'd always stop rolling with the wheels down.

Driving the old bug was kind of how I came to habitually drive so I never turn and brake at the same time. It serves well when driving high center of gravity vehicles too. Brake with the wheels pointed straight ahead. One thing I like about a two wheel vehicle is you can turn while braking hard on the rear brake. I never learned that technique with cars, but there is a maneuver where you lock up the rear wheels with the emergency brake. I wasn't going to try it in an old bug for sure.
 
Handbrake turn? Used a lot in Rallying to invoke oversteer for getting around tight corners. Otherwise, I'm not aware of any driving/racing discipline that says it's OK to brake in a corner. It's always off the brakes before turning in and don't accelerate until you're past the apex.

Dauntless, fair point about ehow. I came across several articles that all said the same thing WRT to roll angle being dictated by the distance beteen the CoM and the instantaneous roll centre. I linked the ehow one because it went a step further in explaining unexpected rollover in SUVs.
 
duane came over yesterday in his buick. a cruisamatic of a car, so maybe that would not be able to get all the way around a battery laying in the roadway. but it is twice the weight of his old accord which would.

he drove the ZENN car. he is a gas masher too. had me pinned in my seat, battery bars dropping like a rock hehe.
 
Punx0r said:
. . . .I'm not aware of any driving/racing discipline that says it's OK to brake in a corner. It's always off the brakes before turning in and don't accelerate until you're past the apex. .

Since you probably can't read the yellow lettering, it's calling the yellow line the trail braking zone. If you 'Heel and Toe' correctly, you're trail braking. You enter the turn basically too fast, but you're easing off the brakes to the apex. You can decrease your radius as you continue through the turn. Also the rear end will give a little but not really powerslide.

A hightech racecar is set up to engage the front brakes first, then disengage them last during the trail braking so to help avoid the rear locking and sliding as you continue braking in the turn. Motorcycle racing you release the rear brake before the turn and ease off the front as you head toward the apex.

The handbrake is supposed to be especially effective on a front wheel drive car, but I've never played with that. It's a favorite in drifting.

The use of the 'Emergency Brake' as Ford originally called it, is reputed to have been a handy technique for moonrunners. None other than 'Rapid Roy' Hall is said to be the inventor of the hand brake 180. When the local sheriff set up a roadblock, he'd stomp on it as he headed straight at the cars, sending the deputies scattering. Then he'd use the handbrake to lock up the rear and set the car sliding to one side. As he did, the foot went back to the floor and the car would be turned around laying down rubber. By the time the deputies were in their cars and after him, he had a mile or more of a head start. Roy Hall was the inspiration for the Jim Croce song 'Rapid Roy,' though the details in the song are all wrong. He was also one of the champion stock car drivers who inspired the creation of NASCAR, ("Hey, 'at's one real NAS CAR you're drivin'.") though he was often racing in the preNASCAR days under an assumed name as he was pretty much always a wanted man, when not actually in jail or prison. (He and his cousin 'Lightning Lloyd' Seay are the subject of such stories as trying to pay in advance for the NEXT speeding fine, since they'd be in a hurry again on the way back.)

Plus, by 1932 he'd be driving the 'Deuce,' the Ford Model 18, (1932-35) the first production car with a V8 and known as the 'Gangster Special' because the criminals caught on to the advantages of the more powerful car while law enforcement remained frugal with their 4 cylinder cars. There wasn't much difference between the 'Deuce' and the regular Model B besides the engine. But when hotrodding took off in the late 1940's, the 'Deuce' was the car of choice even moreso than the much cheaper Model T. Not nearly so many parts to change, especially not the engine.

corner_zones_trans1.jpg
 
this thread started when i expressed disbelief that the feds would be using the low clearance to harass elon because they are biased towards the fat high clearance 4 wheel drive SUV type cars already, because of the US market preferences for fat cars.

so i was watching motor week on PBS this afternoon and they had the mercedes SLS AMG super roadster, $278k, and they showed how it could out drag everything and race around the track at high speed and all the other stuff you cannot do in reality unless racing in closed course race. totally useless car unless you are super rich old man with money to waste and no need to drive it.

so i noticed that this car is gonna be sold in the US and it is even lower than the Tesla so i was really ticked that the feds could get away with forcing elon to waste another $5k to put a titanium shield under the car for no reason except the inability of people to drive a car and avoid stuff in the roadway. but the mercedes gets a pass because it burns gas. godmmmudderfuckers!
 
dnmun said:
this thread started when i expressed disbelief that the feds would be using the low clearance to harass elon because they are biased towards the fat high clearance 4 wheel drive SUV type cars already, because of the US market preferences for fat cars.

so i was watching motor week on PBS this afternoon and they had the mercedes SLS AMG super roadster, $278k, and they showed how it could out drag everything and race around the track at high speed and all the other stuff you cannot do in reality unless racing in closed course race. totally useless car unless you are super rich old man with money to waste and no need to drive it.

so i noticed that this car is gonna be sold in the US and it is even lower than the Tesla so i was really ticked that the feds could get away with forcing elon to waste another $5k to put a titanium shield under the car for no reason except the inability of people to drive a car and avoid stuff in the roadway. but the mercedes gets a pass because it burns gas. godmmmudderfuckers!

A selectable/adjustable ride height system could be a viable solution, allowing for variable road and speed conditions to modify the available space underneath the vehicle. :wink:
 
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