Fly By Wire
Published: 2023-07-31 13:58:40

The automobile has evolved a great deal since its invention in 1886, though it seems the pace of innovation has drastically increased in the past few decades. Today cars are not only much safer than they used to be but also much faster, more efficient, and more reliable on top of boasting new and innovative features such as self-driving technologies. Most of the advantages were brought about by putting computers in vehicles, so let's look into how computers made their way into cars. 

For combustion to occur, there are three necessary components: oxygen, fuel, and a source of heat. For a source of heat, engines use a spark plug that adds enough heat to start the fuel burning.  Next, we need oxygen. Rocket ships bring their oxygen with them because there isn't any in space, but most engines get their oxygen from the air around them. For this reason, all engines are essentially air pumps. The more air an engine can pull in, the more oxygen it should get, the more fuel it can burn, and the more power it can make. There is just one issue. If there is too much fuel going into the engine for the given amount of air, the extra fuel will remain unburned and will be discarded out of the exhaust. Inversely, if there is too little fuel for the given amount of air, the fuel will burn much faster and much hotter, possibly causing components to melt. This is an especially tough issue, because the amount of air that enters the engine is not fixed, but rather increases in correlation with the engine's speed in revolutions per minute. So how do we solve the problem of putting the right of gas into the engine for the amount of air that is going in?

Enter the carburetor. A carburetor works primarily off the 
Bernoulli's principle, which states that air flowing through a constriction will decrease in pressure. Carburetors have a passage, or constriction, that is attached to the air intake side of an engine with a fuel reservoir situated just beneath. When an engine breaths air in, it pulls air through the carburetor's airway causing the pressure within to decrease and fuel is pulled through a port from the fuel reservoir into the airway. 

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/s54s7wpm7wdtad50vt9v.jpeg)

This design accomplishes the goal of providing the correct amount of fuel for the amount of air intake, as when the engine breathes in more air, the pressure inside the carburetor's airway will decrease further, pulling in more fuel. Still, more issues arise. If the oxygen content of the air or the air pressure falters, the carburetor will have no way of knowing! 

A carburetor is simply not feasible for a vehicle that can climb and fall so much in altitude. The answer to this issue is called fuel injection. A fuel injection system holds fuel in a pressurized cylinder called a fuel rail. There is a computer called a CDI that monitors engine speed and timing. When the engine needs fuel, the computer will send power to a solenoid that opens a fuel injector, releasing fuel into the air intake manifold. The CDI varies the amount of fuel it releases by varying the amount of time the fuel injector is open. The CDI monitors air pressure using a mass airflow sensor in the intake manifold. Using a digital sensor to measure air pressure not only solves issues when climbing at altitude but can calculate the correct amount of fuel much more accurately than a carburetor. Furthermore, fuel injection systems can correct themselves should they err by monitoring the amount of unburnt oxygen in the engine's exhaust gas and correcting fuel intake accordingly. For these reasons, fuel-injected motors are much more efficient, all from a technology that was originally designed for aviation. 
	
There's another impressive invention that was borrowed from aviation called fly-by-wire systems. For many years, airplanes actuated their control surfaces using cables connected directly to the yoke and pedals. These fly-by cable systems were not only heavy in terms of weight but also heavy in terms of feel due to friction on the cables and not much ability to use leverage to help fight the force of the wind against the control surfaces. Eventually, planes began using hydraulic systems that provide hydraulic pressure with a pump. To actuate the control surfaces, pressure can be bled into a hydraulic slave cylinder, moving the control systems with very little effort from the pilot.


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/dhqt8iumn2er9fdv4b0q.png)

Cables were still initially used to direct the flow of pressure from the pump to the cylinders, but it wasn't long before it was realized that this job could be handled by electronic servo motors. Not only could this save a substantial amount of weight by replacing the heavy steal cables with electronic wiring, but also a computer can monitor inputs and assist or correct the pilot. On top of making aviation much safer, it also opened the door to planes being able to fly themselves autonomously. Many commercial airliners have autopilot systems that can both successfully fly and land the aircraft, albeit under careful supervision by the pilots. So how does this technology apply to automobiles?

Many of the cars that you see on the market boast driver aids that prevent the brakes from locking, prevent the tires from slipping, help the driver regain control should the vehicle enter a slide, prevent lane departure, adjust speed to match traffic, detect possible collision and brake to avoid them, and in some cases even navigate the car under the careful supervision of the driver. These features are meant to make driving safer, but do they?

Some argue that cars can do too much and should not be able to drive themselves. There are obvious advantages to vehicles driving autonomously but there are a few drawbacks that leave people uncertain. What happens if the computer malfunctions? This is a serious issue in both aviation and automotive alike. There have been cases where autopilot systems have caused planes to crash after the pilots did not intervene due to distraction. Pilot distraction, though, is atypical as pilots are well-trained and follow strict regulations that prevent distraction. Drivers, however, undergo little training and are easily distracted. According to the National Safety Council, "3,142 people died in distraction-affected crashes in 2020." Distraction is already a serious concern on the road, but will autonomously driven cars make drivers more distracted? If it does, could self-driving cars still be safer? Only time will tell.




https://injuryfacts.nsc.org/motor-vehicle/motor-vehicle-safety-issues/distracted-driving/?utm_source=Google_Search&utm_medium=cpc&utm_campaign=Injury_Facts&gclid=CjwKCAjwlJimBhAsEiwA1hrp5joC_lsvWf0Fkkv6Syz0a_M8c4JUVFl1lxxoRsoLCevy4j585RAvyhoCz-UQAvD_BwE