Driving

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overview: autonomous driving autonomous driving: definition, level& basics

How does autonomous driving work and where does the development of the technology stand?? definition, the five levels of automation, examples and market forecasts – simply explained and at a glance!

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Autonomous driving is set to fundamentally change mobility and is one of the major topics of the future.

autonomous driving (english: autonomous driving) designates, according to a definition fully automated driving of a vehicle without a driver. The road ahead is referred to as automated driving described, in which various assistance functions gradually control the engine (acceleration), brakes and steering, respectively. Intervene in these systems. This article covers both autonomous and automated driving.

autonomous driving is one of the four "megatopics" of the automotive industry – the other three are electromobility, sharing economy and connectivity. Driving without a driver will radically change the car and the automotive industry, as well as the function of the car. Most automakers are very active in this area, as are automotive suppliers. In addition, new market players such as sensor and semiconductor manufacturers and mobile network operator competing with established companies in the automotive industry.

Stages (or levels) of autonomous driving

The SAE (scociety of automotive engineers) has defined five levels of automated or autonomous driving. autonomous driving defined. This classification has become established worldwide in the automotive industry.

Stage 0: no automation. Drivers steer, accelerate and brake themselves.

Stage 1: the car has individual support systems such as an antilock braking system (ABS) or electronic stability program (EPS) that intervene automatically.

Stage 2: automated systems take over partial tasks (e.g. B. Adaptive cruise control, lane change assist, automatic emergency braking). The driver, however, retains control of the vehicle and responsibility for it.

Level 3: the car can accelerate, brake and steer autonomously in some sections (conditional automation). If necessary, the system prompts the driver to take control.

Stage 4: in normal operation, the vehicle can drive fully autonomously. However, the driver has the possibility to intervene and "overrule" the system.

Stage 5: fully automated, autonomous vehicle operation without the possibility (and necessity) of driver intervention.

In this video, miklos kiss, head of pre-development driver assistance at audi, explains the five stages of automated driving.

autonomous driving: review

In 1968, the automotive supplier continental the press was presented with a test vehicle based on a mercedes 250 (W119), which drove driverless on the "contidrom" circuit in the luneburger heide region of germany. Lane guidance was provided by a guide wire; sensors supported navigation. The vehicle is designed to test tires under reproducible conditions.

Starting in 2004, the development of autonomous vehicles was significantly promoted by the DARPA Challenge, a competition for unmanned land vehicles organized by the U.S. Department of Defense.

What special forms of autonomous driving are there??

Commercial vehicle manufacturers are using autonomous driving systems to couple multiple trucks via an "electronic tow bar". The first truck will be driven by a driver (if necessary). Partially autonomously) controlled, following trucks drive in sync with the first vehicle and follow at a defined distance. This technology is known as "platooning".

Technology: sensors for autonomous driving

How does autonomous driving work?? Autonomous driving requires various types of assistance functions that interact in the higher expansion stages of the overall system. Examples include braking, congestion, lane departure, turning and parking assistants, as well as adaptive speed control. In addition, various sensor systems.

Autonomous vehicles must be equipped with systems for environment recognition. In addition to cameras, these passive systems include laser, ultrasonic, radar and/or lidar sensors for measuring distance and processing other information from the vehicle’s environment.

Autonomous driving requires different sensor groups: laser, ultrasonic, radar, infrared or lidar sensors.

Sensors permanently detect the vehicle's surroundings - see display

For example, the traffic jam pilot in the audi A8 – which the manufacturer claims is the first true level 3 driving function – is equipped with 24 different sensor systems, including five radar sensors and six cameras.

At the active level, there must be the option of electronic control of the engine, brakes and steering system. The third prerequisite is the linking of all active and passive systems in terms of control technology, while maintaining the necessary safety (see paragraph on "Safety") IT security) and very short response times.

The founders (from left): Rolf Wojtech, Florian Petit, Mathias Muller

Technologies required for autonomous driving outside the vehicle

The higher expansion stages of the automated driving can only be reliably realized with purely in-vehicle sensors and electronics if certain conditions are met (no cross-traffic, no pedestrians). The goal, however, is driverless driving on the longest possible routes and in urban areas. Therefore, the technologies for autonomous driving are closely linked to the trend of connectivity.

Autonomous driving requires the new 5G mobile communications standard.

Vehicles approaching an intersection exchange signals and make z. B. Regulations on right of way (car-to-car communication).

Vehicles can automatically warn following or oncoming cars of hazardous situations and, in the case of them, z. B. trigger emergency braking.

Mobile networks monitor intersection traffic or traffic in entire neighborhoods (car-to-X communication).

Also parking garages, traffic signs, traffic lights, etc. Are included in the communication.

To be able to drive autonomously, the computer also needs information about road works or traffic lights.

Against this background, the expansion of mobile communications networks (5G) is of great importance for the practical use of autonomous driving. In addition, a cloud-based communications infrastructure must be established.

Impact of autonomous driving on vehicle design

Level 4 autonomous vehicles require the driver’s attention only occasionally and on request. At level 5, there are no longer any drivers, only passengers. As numerous vehicle studies have shown, this will have a significant impact on the design of the interior.

Some examples: the instrument panel with steering wheel can be folded away. "real" autonomous vehicles (level 5) manage entirely without a steering wheel. The driver’s seat can be converted into a mobile workstation, or all passengers sit facing each other. For long-distance journeys z. B. To the vacation spot, the seats become comfortable sleeping facilities.

Robo-taxis and minibuses are the first 'use cases' for autonomous driving

Driving without a driver enables completely new interior concepts - here in the Mercedes F015

Meeting in an autonomous shuttle? How people will use the free time provided by autonomous driving cars is still a matter of debate for many

Further interior concepts for autonomous vehicles can be found here:

Futuristic cockpit concept from Conti with large glass surfaces for all displays. The three-dimensional touch display won the 'CES Innovation Award'

Autonomous driving: legal requirements

According to the "Vienna Convention on Road Traffic" of 1968, which applies throughout the EU, the driver of a vehicle must be in control at all times. In 2016, this agreement was amended to the effect that automated systems must be able to. A. Then be allowed to drive if the driver can "overrule" it. Fully autonomous vehicles are therefore not yet eligible for registration in Germany. In other markets such as the USA and China, regulations are more open.

Overall, the legal framework for autonomous driving is complex. Since there is no driver in fully autonomous vehicles, the question arises as to who is liable in the event of an accident. In the current legal system, a vehicle can be registered on its own, i.e. without a keeper, manufacturer, etc., if the vehicle is not in use. Not be held liable for this.

There is also intense debate about the (algorithmically controlled) driving strategy in the event of accidents: how "decides" z. B. An autonomous vehicle when a pedestrian runs onto the roadway? swerve it and drive into oncoming traffic? Does it take collision with a passerby to avoid collision with three pedestrians?

A overview of liability for automated driving cars you can find here:

Self-driving systems - the picture shows a Waymo vehicle - raise legal questions

Insurance and ethical aspects of autonomous driving

Individual accidents with autonomous vehicles cannot be ruled out – at least at present – and generate a great deal of media attention each time they occur. However, there is no question that automated or. Autonomous driving will significantly reduce the frequency of accidents. This trend is already discernible – at least in industrialized nations – thanks to the increasing market penetration of assistance systems.

In this context, there is intense debate about how an autonomous vehicle will behave in the event of an imminent collision: will it z. B. Risking a total loss to protect an unwary pedestrian? This depends on the algorithms that take effect in such cases – legal regulations are still lacking here.

The U.S. state of Arizona has banned Uber from further robo-driving until further notice following the fatal crash of a self-driving car with a woman

The question of data: IT security and data protection

When autonomous vehicles communicate with their environment on a cloud basis, safety-relevant data is transmitted. This presupposes stable and very powerful (radio) networks and requires a high degree of data security (IT security). This means that there must be fallback levels and the risk of attacks must be excluded as far as possible. Guidelines and standards are currently being developed to meet these requirements. Data protection also plays a role. Ultimately, autonomous driving collects, transmits and stores personal (mobility) data.

State of development of autonomous driving

Currently (december 2018), all major volume manufacturers offer mid-range and top-of-the-range models with assistance systems up to level 3. they are also working on vehicles for levels 4 and 5 and have presented prototypes – some of them several years ago.

Some examples from tesla, daimler or volkswagen:

Tesla calls its system autopilot, it runs on level 2. The latest functions are expected to recognize and respond to traffic lights, stops and traffic circles.

Mercedes has developed the (drivable) prototype F015, an example of an autonomous luxury vehicle with an innovative interior design.

VW is targeting the market for autonomous compact vehicles with the sedric concept car, but has also developed an autonomous racing vehicle with the ID pikes peak.

On the ring road around Gothenburg, volvo has set up a test track for a fleet of 100 automated XC 90s.

GM has announced that it will launch a level 5 vehicle without a steering wheel as early as 2019 (see Figure 4).

Technology groups as google (waymo) and mobility service providers such as uber are technically on similar status as the automotive groups.

Whitepaper Cover: AUTOMOBIL INDUSTRIE editorial team

Industry barometer

Study: development in automated vehicles

Also tier 1 automotive suppliers bosch, continental, aptiv, ZF and schaeffler have been working on complete or partial systems for autonomous driving for many years. Aptiv is using z. B. A test track on public roads in wuppertal.

Overall, the industry is making very high investments and development expenditures in this area: "in the german automotive industry alone, around 20.000 developers with connected and automated driving." (herrmann/brenner, S.29) 1

Artificial intelligence: autonomous driving and deep learning

In practice, the sensor systems for the automated resp. Autonomous vehicles are already achieving good results today – provided that the environmental conditions are favorable. The problem is z. B. In case of snowfall, missing lane markings and unclear traffic situations. Development work still needs to be done here. This is a field of application for artificial intelligence (AI) with neural networks: with the help of "deep learning," the sensor networks learn, for example, to distinguish objects from people with a very high accuracy rate and to recognize the direction in which pedestrians are walking.

Sepp Hochreiter, 51, heads the Artificial Intelligence LAB at the Linz Institute of Technology (LIT)

Future of autonomous driving: market outlook and forecasts

Sales forecasts vary widely – as there are many factors to consider. The consensus, on the other hand, is that autonomous driving will be part of everyday life for many vehicle users from 2030 onwards. The information service IHS markit expects global sales of sensor networks to reach approximately 6.5 million cars with level 4 and from just under 4.5 million fully automated level 5 vehicles.

According to general estimates, autonomous driving will initially be used in defined markets. The first step will be taken by robo-taxis and minibuses with fixed stops or in fixed districts (Fig. 6). In germany, a partially automated shuttle is driving in the bavarian bad birnbach.

Manufacturers, suppliers and institutes are increasingly testing on public roads

On the university campus of singapore such a "robotaxi" has already been in use since 2016. Volkswagen plans to offer cab services with the VW sedric in two to five cities starting in 2021. Waymo, uber and others are driving similar projects in the U.S. and asia.

In addition to autonomous cabs and minibuses, there will also be "autonomous" multi-purpose vehicles – as a third vehicle category – in the premium segment.

How autonomous driving is changing mobility?

According to experts, new types of mobility will also become established with autonomous vehicles. There are already practical examples of this z. B. In phoenix/USA, where the google subsidiary waymo has announced the launch of a fleet of autonomous cabs for december 2018. volkswagen is planning to do the same with its "moia" shuttle service for hamburg and other cities – initially with drivers.

So it’s not just new entrants like waymo and uber that are entering the automotive market. New business models are also taking hold that could replace the traditional model (car purchase by the driver). There is a close connection here to another "megatrend" in the industry: the sharing economy.

Autonomous driving: social and macroeconomic benefits

Autonomous driving brings significant time benefits to passengers, especially in cities with high traffic congestion, because they can save time in the car z. B. can use for office work. In addition, the absorption capacity of the roads is increased several times over. In addition, groups of people who cannot drive themselves (the elderly and the sick) can also participate in individual transportation. And the significant drop in the number of accidents is reducing the (considerable) social costs z. B. Due to absenteeism from work, hospitalization, etc. In addition, traffic is becoming increasingly congested, especially in city centers. This results in reduced energy consumption and correspondingly lower emissions.

Autonomous driving: conclusion and open questions

In summary, autonomous driving will not only change vehicle technology, but also the functions of the car and mobility as a whole. New business models will emerge and new competitors (technology groups, mobility service providers, network providers…) will enter the automotive market.

Among the open issues are the payment models. What fees are charged for the use of data networks (car-to-car, car-to-x communication)?? Who offers these services: the car manufacturer or the network operator?? Equally open is the question of who owns (and who commercializes) the data generated by the autonomous vehicle and passed on, for example, to subsequent vehicles: the car manufacturer, the manufacturer of the assistance system, the service provider or the network operator? These two questions alone show that autonomous driving can also cause real disruption at the level of business models.

Industry Barometer

"index automated driving": competition of the autonomous nations

Further information on autonomous driving

1. Our development channel: up-to-the-minute news, specialist articles and insider knowledge

2. Our media library: studies and monthly updated M&A transactions of automotive suppliers

We need your help!

We put a lot of work into this article to keep it relevant and up-to-date. Give us feedback and let’s hear what interests you most about autonomous driving technology. Which questions are still open? Which aspect should we look at in more depth?

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Overview of autonomous driving: sources

1 andreas herrmann, walter brenner, the autonomous revolution. How self-driving cars are taking over our roads. Frankfurter allgemeine verlag, 2018

N.N., insurers want rules for autonomous driving. In: FAZ, 21.11.2018

DARPA challenge. Wikipedia, retrieved on 3.12.2018

Maren eitel, why in the digital world the covers are dark. Interview with johann jungwirth, head of mobility services at volkswagen AG. In: porsche consulting magazine no. 19/2018, S. 11ff.

Federico magno, it’s a matter of bare existence. In: automobil industrie, special issue transformation E, 2018, pp.6/7

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Cameras offer different autofocus options. It’s not easy to tell them apart. What are AF-S and AF-C? Which autofocus mode is the right one for which motive?

What is an autofocus mode?

Autofocus modes refer to the way in which their autofocus at focus on a subject behaves.

To start with, it is important to understand how autofocus works in general:

First press the shutter button halfway. This sends a signal to your camera to start focusing. Then press the shutter button all the way down. Your camera triggers a (hopefully focused) shot.

autofocus mode tells the camera what to do when you press the shutter button halfway down. In other words:

Should the camera find the focus as soon as possible and then stop focusing?
Or is the camera supposed to find focus, but then keep focusing when the subject changes?

This is what autofocus mode is about.

By the way, there is another important mode: manual focus. It is not technically an autofocus mode and is therefore not covered in this article. But manual focus is an important technique to be familiar with. Because it can be useful in many situations.

There is no universal autofocus mode. The AF mode must be set correctly depending on the photographed subject.

What are the common autofocus modes?

If autofocus modes tell the camera what to do when you press the shutter button halfway down, which modes can you choose? And what do they do?

In general, there are two basic AF modes:

AF-S (aka single frame AF, single AF) and AF-C (aka focus tracking, continuous AF or servo).

There is a third autofocus mode, AF-A, also known as automatic focus, but it is not found on all cameras. It is a fully automatic mode with no possibility of intervention. We will come to this later.

Now let’s look at each AF mode in turn:

AF-S autofocus mode is often the default mode for photographers because it works in a very simple way:

When you press the shutter button halfway, the focus is locked on the area below your AF point. The focus remains locked until you release the shutter or take a photo.

In other words, when you press the shutter button halfway down and lock focus, this point doesn’t change anymore. Even if you are focusing on a bird that is flying away or on a car that is moving.

The focus point is fixed as long as the shutter release button is pressed halfway!

This is in contrast to AF-C, which I discuss in the next section:

AF-C Focus Tracking Auto Focus Mode AF-S

AF-C is a more complex autofocus mode. It works by continuously trying to lock focus on the subject as long as you hold down the shutter button.

So as soon as you press the shutter button halfway down, the focus starts to move. It can focus on a person, a rock, a wall, whatever. If the subject moves forward or backward under the autofocus point, the camera changes the focus point and follows it. Even if an object comes between the camera and the subject, the focus is recomposed. But this depends on other options that can be set, more on that later.

Note that in AF-C mode, your camera may constantly change the focus point to follow a subject. So this is interesting for sports photography, moving animals, car racing and the like.

AF-A is not available on all cameras; it is meant for photographers who are just starting out. It is virtually an automatic system that decides for itself which mode is the right one at any given moment. And that tends to go wrong. It basically switches back and forth between AF-C and AF-S depending on whether your camera detects a moving or a stationary subject.

I personally do not recommend the use of AF-A. because you don’t have the same level of control as with AF-C or AF-S. With AF-A you never know exactly what will happen when you press the shutter button. Because the camera may recognize whether the subject is moving or still, but it is not perfect at doing so.

When to use autofocus modes?

As I said above, I do not recommend using AF-A.

But what about AF-S and AF-C? When does it make sense to use these two modes?? This is very simple:

If you are shooting still subjects, use AF-S. And for moving subjects, use AF-C.

This way you can shoot at still subjects use helpful techniques, such as. B. Focusing and recomposing, where you focus on your subject and then recompose the image. This is especially interesting in portrait photography and when you focus on an off-center subject.

At moving subjects on the other hand, you can track your subject throughout the frame. The focus is then automatically tracked and the subject remains sharp in any case, even with a racing car.

Does this make sense? Well, what I suggested, with AF-S for still subjects and AF-C for moving subjects, will not always work perfectly.

For example, what if you’re dealing with a subject that’s mostly still, but occasionally moves?? How z. B. A bird foraging? For those moments when the bird is standing still, you should use AF-S so you can lock focus and take a series of shots. Also, you can always re-focus and re-aim if you need to.

However, for the moments when the bird is moving, you should use AF-C to get nice action shots. Of course, you can always switch between modes, but by then it may be too late.

Here is the solution: the AF-ON button.

What is AF-ON autofocus and when should you use it??

AF-ON button autofocus is an alternative method to focus with your camera. Instead of focusing by half pressing the shutter button, it happens with a button instead. It is on the back of the camera (AF-ON button).

Basically, you set your camera to switch the AF trigger from a half-pressed shutter button to AF-ON button.

The special feature of back-button AF is that it decouples the focusing mechanism from the shutter release button.

So if you want to focus and track your subject, you can press and hold the AF-ON button on the back while you shoot. But as soon as you want to lock the focus (i.e. when the subject stops moving), you can simply stop pressing the AF button.

Focus is maintained, and you can continue shooting with the front shutter release button.

For this reason, the AF-ON method is a common way for action, street, and wildlife photographers to focus.

However, this method is only useful to use if in the menu individual functions "AF-activated" specifies that autofocus is not activated when you press the shutter button, but only with the AF-ON button.

What is AF-lock?

AF lock is a setting that is offered on many cameras. It allows you to focus normally, but then lock your focus point even when you release the shutter button.

It’s a good way to keep the focus point whether you shoot with AF-C or AF-S. But I don’t recommend using them regularly. It is better to lock the focus by half-pressing (and holding) the shutter button or switch to back-button AF.

What are AF point modes?

AF point modes are the second main feature of autofocus systems.

Instead of telling the autofocus how to behave in the broadest sense, the AF-area modes determine the distribution of the AF-areas and how they can be used.

What this means? Autofocus points are simply points that can lock focus. Points can be active or inactive. So if you have an active autofocus point in the center of the frame and you press the shutter button halfway down, that point will focus on the object in that part of the frame.

However, if the center point is inactive, the autofocus system will completely ignore that point and use another (active) point to focus on.

Ideally, every point would be active and the camera would magically know exactly where you want to focus; and which autofocus points to use. Instead, you need to specify which AF points you want to use. Or at least you have to tell your camera to select the AF points by itself, which doesn’t always work well.

This is what AF point modes are all about:

You specify which points to use and how they should function. Now, different camera systems offer different AF point modes. So there is no uniform bandwidth of options, as is the case with the basic autofocus modes. But there are some common features, which I will explain in the next section.

What are the common AF point modes??

In general, there are three main autofocus field modes that are available on most modern cameras.

These are the AF-area modes you should be aware of, as quickly switching the area modes can be very useful when taking pictures.

Single point

The single-point autofocus point mode is a fairly simple option.

You use the camera buttons or joystick to select an AF point that you want to activate. And then your camera will focus only in this area.

Note that this is the most precise of the AF point modes, so I recommend this mode if you can take some time and focus deliberately.

A good strategy is to choose the center AF point, aim it at the part of the photo you want to be sharp, finally half-press the shutter button to lock focus, then recompose and take the shot.

By the way, there are other modes for single point AF fields; some cameras offer z. B. A mode where you can first specify which point you want to activate. When your subject moves, the surrounding AF points become active and you can continue to focus on the subject.

3D tracking

AF tracking algorithms are getting better and better, which means that tracking autofocus modes are becoming very popular.

in tracking modes, you can usually have your camera identify subjects in the image (based on many characteristics, including motion). Or you can select the first focus point. Then your camera will do everything it can to "stick" to the subject. And even if it moves around the viewfinder and even behind objects. By the way, at nikon this procedure is called lock-on.

AF tracking modes can also include a form of eye AF, where the camera identifies an eye and tracks it through the image. This is very useful for portrait, pet and wildlife photography.

I recommend using the tracking modes whenever you are confronted with moving subjects of any kind. And especially if your camera can handle complex movements. The tracking function is popular with wildlife, bird, and sports photographers, as it allows for sharp shots even when the subject is moving.

It should be noted, however, that AF tracking is not as precise as other focusing modes. And that dependence on the camera’s tracking algorithms can sometimes result in missed shots. This is especially true when shooting in difficult situations, e.g. B. In backlight or low light conditions.

The auto AF metering mode works as you would expect:

You press the shutter button halfway, and your camera decides where to focus. In other words, you have no control over the AF points; that’s entirely up to the camera. In situations where you are not dealing with moving subjects, but don’t have time to focus carefully, automatic AF point modes are a good option.

But they can’t predict what they want to focus on, which means they often focus randomly, which is far from what they wanted to achieve. That’s why I generally recommend using a single-point AF point mode for still subjects and AF tracking for moving subjects.

autofocus modes: conclusion

Now that you’ve finished this article, you should know all about the different autofocus modes, including AF-ON button, AF-lock, AF-area modes and more.

And you should be able to select the right focus mode for the right situation. This way you will always get sharp pictures!

What are AF-area modes?

AF-field modes are ways to control the different autofocus points. They allow you to select individual AF points or instruct the camera to track the subject through different parts of the frame. It is important that you select the correct AF point mode for your shooting situation. Because that way, you can maximize the number of sharp shots you get!

What is AF-C compared to AF-S?

AF-C is a continuous autofocus that continuously focuses while you keep it active. AF-S, on the other hand, is a one-time autofocus, d.H. When you press the shutter button halfway down, the focus is locked; only when you release the shutter button can you refocus again.

What is the best autofocus mode??

There isn’t really one best autofocus mode; both AF-S and AF-C are good in different situations. AF-S is great for working with stationary subjects. AF-C, on the other hand, is perfect for tracking moving subjects in the image, as it instructs the AF system to continuously lock focus, even while taking photos.

What is the AF-ON button?

The AF-ON button activates an advanced method of autofocus that decouples the shutter release from the focusing mechanism. Instead, only the AF-ON button on the back of the camera can activate the autofocus of the camera. You just have to press the button on the back and your camera will start focusing. This is useful in situations where you want to focus continuously and then lock focus quickly.

What is the AF-lock / AF-L?

AF-lock function locks your focus point even when you take your finger off the shutter release button.