kateoplis:

1988 Peugeot Oxia Concept

How Anti-Lock Brakes Work:

The theory behind anti-lock brakes is simple. A skidding wheel (where the tire contact patch is sliding relative to the road) has less traction than a non-skidding wheel. If you have been stuck on ice, you know that if your wheels are spinning you have no traction. This is because the contact patch is sliding relative to the ice (see Brakes: How Friction Works for more). By keeping the wheels from skidding while you slow down, anti-lock brakes benefit you in two ways: You’ll stop faster, and you’ll be able to steer while you stop.

There are four main components to an ABS system:

• Speed sensors
• Pump
• Valves
• Controller

There are many different variations and control algorithms for ABS systems. We will discuss how one of the simpler systems works.

The controller monitors the speed sensors at all times. It is looking for decelerations in the wheel that are out of the ordinary. Right before a wheel locks up, it will experience a rapid deceleration. If left unchecked, the wheel would stop much more quickly than any car could. It might take a car five seconds to stop from 60 mph (96.6 kph) under ideal conditions, but a wheel that locks up could stop spinning in less than a second.

The ABS controller knows that such a rapid deceleration is impossible, so it reduces the pressure to that brake (via the valves) until it sees an acceleration, then it increases the pressure (via the pump) until it sees the deceleration again. It can do this very quickly, before the tire can actually significantly change speed. The result is that the tire slows down at the same rate as the car, with the brakes keeping the tires very near the point at which they will start to lock up. This gives the system maximum braking power.

When the ABS system is in operation you will feel a pulsing in the brake pedal; this comes from the rapid opening and closing of the valves. Some ABS systems can cycle up to 15 times per second.

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thisistheverge:

The Batmobile is real: Audi’s self-driving car picks you up on command

There are self-driving cars, then there are self-driving cars.

Today at CES, Audi showed me the former. The A7 parked in the cul-de-sac of Las Vegas’ luxurious Mandarin Oriental hotel looked no different than any other that you might see on the street, but this was a special demonstrator of Audi’s “piloted driving” system for automated parking. It works like this: you walk out of the mall, you want your car. You open an app on your smartphone, press a button, and the car drives out to you. Pretty awesome — and it works the opposite way, too.

Is new car smell toxic?

What exactly is new car smell made of, anyway?

That’s a tough question to answer. We can start by asking just what it is that we think we’re smelling when we climb into a brand new car interior. Some people think it smells like leather, but only luxury car interiors contain much in the way of actual leather and new car smell can even be found in economy cars. Other people think it smells a bit like plastic, but good plastic, not the cheap kind that $1.99 toys are made out of. Some people think it smells like … well, a whole lot of different chemicals.

That last group is closest to the mark. There really are a whole lot of chemicals making up the interior of a car and some of them release volatile organic compounds (VOCs) into the car’s interior, a process that has the somewhat unpleasant-sounding name “outgassing.” It’s these VOCs that produce new car smell, though some of them produce no odor at all. Some of these volatile chemicals, like ethyl benzene and formaldehyde, are also found in paints and glues, and they can cause problems like dizziness, headache, allergies or even cancer when inhaled in large enough quantities or for long enough periods of time. Some people have compared inhaling new car smell to glue sniffing or even sick-building syndrome.

But are there enough of these compounds in new car smell to make a fresh car interior truly unhealthy or would they require more exposure than the average driver is likely to get to them? The best way to find out is — you guessed it — to do a scientific study.

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One Last Trip for the Endeavour:

Have you ever seen one of those “strongman” competitions where someone pulls train cars or maybe a few city busses with a huge rope wrapped around his waist? There’s no arguing that it’s an impressive show of power. And, at least for me anyway, it’s always a little bit comical to see someone so (relatively) small moving such a large object. It’s like watching a tiny ant carrying a huge leaf. It’s visually absurd.

This Saturday, there’s going to be another amazing show of strength (and I’m sure a fair amount of that visual absurdity, too) as a stock 2012 Toyota Tundra CrewMax half-ton pickup tows the massive, retired space shuttle Endeavour to its new home.

It’s well-known that NASA’s space shuttle program has flown its final mission. And if you’ve been paying attention to the news lately, then you also know that the retired space shuttle Endeavour has made its way across the USA to Los Angeles International Airport (LAX). Not under its own power, but by riding on the back of NASA’s Boeing 747 shuttle carrier. (That’s another strange sight, incidentally.) But the craziest part of the journey still lies ahead. On October 13th, the Endeavour — all 300,000 pounds of it — will be towed (via a special dolly built by the Sarens Group, a heavy lifting and engineered transport company), on a 12-mile trip through the streets of Los Angeles to the California Science Center where it will remain on display for the public. Heavy-duty industrial equipment will haul the shuttle most of the way, but then a Toyota Tundra pickup truck — with a 10,000-pound towing capacity — will take over the towing duty for the final quarter mile.

A 300,000-pound load towed by a vehicle with a 10,000-pound towing capacity? That doesn’t add up, does it? How does the (relatively diminutive) Toyota Tundra accomplish what the (massive, purpose-built) NASA Crawler-Transporter normally does?

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How Hybrid Cars Work

Have you pulled your car up to the gas pump lately and been shocked by the high price of gasoline? As the pump clicked past $20, $30, $40 or even $50, maybe you thought about trading in your car for something that gets better mileage. Or maybe you’re worried that your car is contributing to the greenhouse effect.

The auto industry has the technology to address these concerns, specifically through the hybrid car. There are a lot of hybrid models on the market these days, and most automobile manufacturers have announced plans to manufacture their own versions.

But how does a hybrid automobile work? What goes on under the hood to give you 20 or 30 more miles per gallon than the standard automobile? And does it pollute less just because it gets better gas mileage?

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5 Strangest Vehicles Ever Made:

Designing vehicles is clearly a science — well, lots of sciences, really. Especially if you consider the engineering, physics, metallurgy, chemistry, computer science and other “hard” disciplines required to make a machine that’s air-, road-, or sea-worthy.

Designing vehicles also happens to be an art.

Alas, as with any category of art — or attempt at art — vehicle inventors, designers and manufacturers have come up with some pretty perplexing prototypes over the years. While we may not see these quizzical and often comical contraptions every day, we do generally benefit from their legacy. By pushing the boundaries of what’s imaginable, they’ve allowed us to keep expanding the limits of what’s possible, in making vehicles that are more aesthetically adventurous, more versatile, more efficient and, of course, more fun.

Without further adieu, read on for the 5 Strangest Vehicles Ever Made.