The Future of Driving
Communication concept of an Intelligent Transportation System
Originally released under ‘Intelligent Transportation System, Mobility in Digital Transformation — Outlook: Vehicle’ as Bachelor thesis for the Bachelor of Arts at the FH Aachen University of Applied Sciences. Sharing my insights and ideas …
How much will our future differ from today? Both strong and only slightly.
More of us will reach the 100. Things are getting faster and cheaper. Our resources will decrease while our technological capability continues to increase. Things are getting faster and cheaper. But a much more interesting question is: What’s not going to change in the future? Our basic needs will probably remain the same. People will still sleep, eat, work, and travel from one place to another. The latter is the subject of this paper.
How will mobility evolve in the next few years?
What problems are we facing?
And what do the solutions look like?
A vision of the future.
Objective
Mobility characterizes our everyday life; in which we strive for efficient transportation. The car is our most important means of transport. Considering current technological developments and digital trends, the aim of this work was to develop a future-oriented communication concept for an Intelligent Transportation System. Despite its visionary approach, it aims to show a realistic perspective for vehicles.
Who does not think about the future, will soon be very worried. — Confucius
With Industrialization Came the Mobility Revolution
At least since the 19th century and finally during the Gründerzeit (founders’ period) in Central Europe, mobility has been growing rapidly and has contributed significantly to an accelerated lifestyle ever since. Mobility is now an inherent part of our life and business; and has become synonymous with freedom, prosperity and individuality.
Hardly anything is of comparably great, general significance in a globalized society. Driven by mobility, there are always new development potentialities. Although this is also associated with risks and dangers, it offers mainly opportunities for improvement. The mobility industry benefits especially from new technological advances.
The uniform 9-to-5 rhythm of life with its rigid separation of working time and leisure gives way to a more flexible and mobile lifestyle.
Nowadays, we are always urged to be mobile — not only professionally but also privately. The increasing demand for mobility results in more and more new working and living spaces.
The Need for Individual Movement
Within Germany, more than one trillion kilometers of traffic performance are generated annually — 80% of this is attributable to motorized private transport.*
On the one hand, the fact that our mobility behavior will continue to increase in the future can be deduced from past years, in which passenger traffic in Europe grew by a third in total between 1990 and 2010 alone.* But even a long-term forecast to 2030 shows that a further increase of around 10% in passenger car traffic and almost 40% in truck traffic is expected in the coming years.* With the need for individual transportation and despite the demographic change, the car remains the number one means of transport.
The importance of the car is confirmed in terms of the worldwide vehicle population, which has doubled in the last 20 years, so that it exceeds one billion since 2010.* Even the decline in our population (e.g. Germany) does not lead to a reduction in car ownership and the aging society will use the car more than the previous generations in the future.
The Road as the Dominant Mode of Transport
With an ascending traffic volume, driving is becoming progressively demanding and stresses not only drivers, but also the streets, that bear the brunt in comparison to other mobility options. Especially in the urban environment, we are already encountering stress limits today. More and more often we are confronted with the problem of efficiency in road traffic, which is reflected daily at rush hours in the congestion of the road network.
A supposedly important part for coping with high traffic volume is road construction. As part of this, highways receive additional lanes, bypass roads are built and intersections are getting reconstructed. However, a simple roundabout makes it much more efficient to handle heavy traffic, as it significantly contributes to the improvement of traffic flow. At the same time, the lower speed, better visibility and the much smaller number of possible collision points make the roundabout traffic safer compared to an intersection.
The limited spatial and economic possibilities for capacity expansion in Germany do not permit infrastructural expansion as in the futuristic model of Brasilia. So improving transport efficiency can not be resolved nationwide by building new roads. An interesting example of this and the fact that the resulting additional route option can even produce the opposite of the desired result is proved by Braess’s paradox*. Overall, the development of new ways rarely leads to a significant optimization of traffic flow.
If you take a closer look at road traffic and the road traffic system, you soon realize that we often (have to) stop at intersections because it is required by today’s traffic regulations. No matter if there’s a red light, a stop or yield sign or due to the priority-to-the-right rule. In addition, we are often prompted to stop, although there are no other road users in the immediate vicinity. These steady and sometimes unnecessary braking and acceleration processes can be attributed to a too rigid and inflexible traffic system. Even the allegedly modern and helpful systems of induction loops in front of traffic signals do not recognize road users early, but only immediately before.
An Outdated Transportation System
Our traffic is still controlled by traffic management, which is nearly the same as decades ago. A look at the history of road transport shows that at the time of the first traffic lights, the traffic volume was much lower and the problem at this time was not efficiency, but that the safety at urban junctions should be ensured. Also, the use of the first official traffic signs — at that time called ‘warning signs’ — prescribed the use mainly for danger spots outside of localities.
With the rise in mobility, countless other traffic signs have been added since the last century, which form the basis of our traffic guidance today. New technical infrastructure in the field of road traffic telematics such as electronic traffic control systems are rare. And even the possibility of variable message signs, ramp metering or temporary emergency lane opening does not cause a revolution in road transportation. Our transport system is simply out of date.
The first traffic signs in Germany were warning signs at level crossings.
In fact car manufacturers and technology companies are trying to make driving on our daily routes easier. Although a vehicle with all its cameras, sensors and assistance systems increases ride comfort, it does not get us to our destination faster and more efficiently. Also, navigation devices — whether installed or in our smartphone — do not really help us with more efficient coping with the traffic. We receive real-time information about traffic jams and traffic accidents, road works and road closures, which always calculates the fastest route; however, the alternative options in route selection are very limited, especially for shorter distances, so that congestion can not be effectively avoided.
Around us, ever smarter systems emerge; from the telephone to our homes — technical progress makes it possible. However, our road transport system has not yet adapted to the development of mobility. But this is where change must take place in order to enable efficient travel in private transport in the long term: the transport system itself.
The fact that the problem of efficiency can be solved right there is shown by a joint research project by MIT, ETHZ and CNR, which illustrates that existing road capacities can also be better utilized through intelligent traffic management. ‘Light traffic’ demonstrates a (still) utopian scenario in which autonomous vehicles do not have to stop to cross the intersection, since a slot-based right of way regulation takes place.
Increase of Traffic Efficiency
With the digital transformation of mobility, there is a growing interest in a cooperative Intelligent Transport System (ITS) that can handle current and future traffic volume in individual transport efficiently, safely and in an environmentally friendly manner.
The overarching goal is to make better use of the existing road network, to avoid traffic disruptions and to significantly reduce travel times. Facing technological progress, our transport system must not remain backward, but should contribute significantly to the mobility revolution in the digital age.
An important factor here will be the collection and evaluation of traffic-related data of all involved stakeholders, components and systems. Both public and private data sources — which are of relevance for transport — form the basis and prerequisite for digital traffic management. This includes not only transport infrastructure components, but also road users and their technical systems.
Illustration by German Association of the Automotive Industry (VDA)
Intelligent Transport Systems (ITS) are systems that use information and communication technologies in road transport and at the interfaces to other modes of transport.— Federal Ministry of Transport and Digital Infrastructure*
Digitalization
In order to create a common, up-to-date knowledge base, an open exchange of information between vehicles (C2C, Car-to-Car), as well as between vehicle and infrastructure (C2I, Car-to-Infrastructure) must take place. Vehicles communicate data from various sensors, devices and cameras, including their position, speed, vehicle type and direction of travel, or special events such as emergency braking or a vehicle malfunction. At the same time, the infrastructure supplements real-time data communication with additional information on construction sites, road closures and road conditions. The digital traffic control system analyzes and interprets all information and creates a complex image of the traffic situation. Additional relevant factors such as weather conditions are also considered here. The insights make traffic ultimately predictable.
With full penetration with V2X communication-based features, an annual economic benefit of up to € 6.5 billion could be achieved through avoided road accidents and € 4.9 billion by avoiding environmental pollution. — VDA
Connected driving
In order to avoid a traffic infarction, the seamless linking of the individual carriers has been pursued for several years as a tried and tested means by the automotive industry and transport institutions. According to experts, data from around ten percent of the vehicles are sufficient to reliably map the traffic situation.
The Federal Ministry of Transport and Digital Infrastructure also sees the key to optimizing traffic in C2X communication and supports the use of innovative information and communication technologies. These measures also include the implementation of the future mobile communications standard 5G, which ensures faster transmission of larger amounts of data and higher network stability. With the ‘Digital Motorway Test Bed’ on the German Freeway 9 in Bavaria, which was launched in September 2015, Germany offers a space for joint testing of connected and automated driving for the automotive industry, the digital economy and science.
In the joint mapping service HERE of the competing German car manufacturers Audi, BMW and Daimler, it is agreed to let connected vehicles exchange anonymized data from their sensors. And European standardization organizations have also set communication standards for the interoperability of cooperative systems, which define message formats, quality standards, security and privacy aspects for C2X communication.
The chance for increased efficiency in the road traffic system lies in the digital traffic management, which is made possible by the upcoming on-board as well as infrastructural introduction and expansion of the technical systems. With the digitalization and seamless linking of traffic it opens up completely new possibilities from the insights gained data to create value.
Digital Traffic Management
The resulting solution pursues the idea of actively reacting to the traffic — being able to influence and coordinate it and, as a result, to optimize the flow of traffic. Here, the entire shift of the traffic guidance towards the driver or directly into the vehicle itself constitutes the decisive change of the intelligent traffic system. The digital communication of traffic signs, regulations and other traffic-related information now enables dynamic traffic management.
A no longer rigid, but now flexible and changeable traffic control system offers an automatic adaptation to different situations. This responsiveness also includes the individual assignment of traffic regulations. Specifically, this means that the traffic infrastructure, for example, communicates data on right-of-way regulation, traffic lights, speed limits or site information to each vehicle — always in direct relation to vehicle, route and traffic conditions.
In the past, a farmer could fall asleep on the coachman’s box. The horses found their way home without him navigating. With the modern technology of self-driving cars we are again just as far. — Matthias Eberling, Writer
Autonomous Driving: An Outlook
When talking about connected cars, Autonomous Driving is often mentioned in the same sentence. Our high-tech cars are becoming automated means of transportation that even make driverless, autonomous driving possible. As a driver, the human being steps completely into the background and hands over the task to the vehicle.
Highly Automated Vehicles will become more and more popular in our lives. Legitimately, because according to accident statistics is the human driver is the cause 90% of the cases, for example due to distraction, inappropriate speed or too low safety distance to the vehicle ahead. Only rarely is an accident due to a technical defect. Cars are getting safer in traffic accidents; airbags, stronger bodies and automatic emergency call systems contribute to this. With connected driving we are now facing a security revolution in traffic: Thanks to the advanced driver assistance systems developed in recent years, accidents can be avoided right from the outset. Combined with the connected transport system, the new technology acts as a multiplier as it improves traffic flow by increasing capacity on highways by up to 80 per cent and on urban roads by up to 40 per cent.*
However, complete automation is linked to some changes in road traffic. An important step, if not a requirement, is the digitalization of traffic management. Our road signs are made for human drivers; computer-controlled vehicles basically have no need for it. Car cameras would never have problems identifying signs or allocate light signals at complex intersections. And road workers can communicate hand gestures via wireless beacons that send electronic signals to oncoming traffic.
Self-Driving Cars Won’t Work Until We Change Our Roads And Attitudes*
The human remains as a driver
But it does not all speak for a rapid spread of autonomous driving within the next few years. Christopher Hart, Chairman of the National Transportation Safety Board (NTSB), which is involved in the investigation of accidents in the transportation sector, expressed skepticism in an interview* with MIT Technology Review about whether full automation of road traffic would ever occur. Thus, interpreting complex situations is the biggest problem; because no software developer will be able to take all possible situations into account. This requires artificial intelligence that can learn things independently.
As with much safer means of transport with autopilot function in air or rail traffic, the car will not be able to do without a human co-pilot completely in the medium term. In critical situations such as take-off and landing, people still take control. Closed systems are required, as is sometimes the case with airport railways, to ensure that driverless traffic is used. And even such a system is externally monitored and can be controlled by humans in an emergency. Our road traffic system with its complexity is the blatant opposite of this and has a much higher risk potential. Added to this is the fact that people do not like to give up their control — especially when it comes to their own safety.
Apart from that, most people enjoy driving. It is not for nothing that motor sport enjoys constant popularity. This leads to the conclusion that we will not watch remote-controlled or robot-controlled racing cars (like the Robocar) in the near future.
The challenge will be to design a system that supports all levels from assisted to automated to autonomous driving.
Since there will still be human drivers despite digital and direct communication with the vehicle, the road traffic system must at least continue to be able to visually communicate traffic guidance to a human driver. And even when driving autonomously, the display of the traffic regulations would help to build up confidence in the vehicle and shorten the familiarization period.
Head-up Display
The digital communication of traffic signs and signals within the vehicle requires a method in which the driver can keep his eyes on the road at all times — just like when reading analog traffic signs. So why not continue to use the medium through which the driver looks anyway: The windshield.
Originally developed for combat pilots, the first head-up display (short: HUD) was used in an Oldsmobile Cutlass Supreme in 1988. It contained the most important information of a combined instrument: Speed, flashing signal, high beam and fuel gauge. Erstwhile intended for the high-end clientele, it is now used or at least offered as an option by almost every high-end car manufacturer and is enjoying increasing popularity. Toyota, Hyundai and General Motors expect that the windshield will soon establish itself as a display medium with increasingly advanced and cheaper technology.* It can therefore be assumed that in the near future every new vehicle will be equipped with a head-up display.
The moment you read 100 km/h from the speedometer, you have already moved 28 meters further.
When reading a conventional instrument panel in a car, the gaze must be temporarily averted from the road. Accomodation takes place because the eyes have to adjust to the shorter visual distance; only then does the flow of information begin. The focus then shifts back to the visually more distant traffic situation. This process takes an average of one second.*
Thanks to the display via the windshield, all relevant information is brought into the driver’s field of vision and appears optically outside the vehicle. This impression is created by a HUD and has the ergonomic advantage that the eye no longer has to focus on the near and far range, making driving more comfortable. As a driver, you feel much safer and more relaxed because all important information and warnings appear directly in the visible area and critical situations can be detected faster.
Goodbye traffic sign jungle!
The transfer of all traffic guidance components to the vehicle and the digital presentation via the head-up display allows a significant reduction of the cognitive information overload, as no irrelevant signs but only important information for the driver are communicated. The Intelligent Transport System performs the filtering of traffic signs in a similar way to a road control system, but with a much more individual addressing. The locomotion in the road traffic is facilitated and the driving comfort can be increased noticeably.
A necessary consequence of this dynamic influencing possibility is the complete removal of all physical elements of traffic guidance such as traffic signs, signalling systems and road markings, which literally stand in the way of digitalization. Viele Verkehrszeichen werden durch eine intelligente Integration in das System überflüssig und können künftig auf passendere Art und Weise kommuniziert werden. Thanks to C2X communication, conditional additional signs such as ‘residents only’ or ‘slippery when wet’ are a thing of the past and can be solved by means of situational warnings and notifications if necessary. Road signs are facing a similar fate to phone booths or cassettes. In the future, they will be just as obsolete. However, this has further advantages.
It isn’t a question of whether street signs will someday vanish, but when. — Brian McClendon, Head of mapping at Uber
In the dark, visibility of traffic signs is often restricted. Despite the reflective surface, the perception cannot be compared with that in bright daylight. Poor weather conditions make them even more difficult. Unlike physical road signs, the traffic regulations are constantly visible via the HUD so that the driver cannot overlook any signals and no longer has to actively look for them.
Material, assembly and maintenance costs for the traffic signs are eliminated due to the ‘relocation’. Although costs for personnel, data maintenance, monitoring, technology and, above all, the development of such digital traffic management will continue to be incurred, the ‘costs per sign’ can be reduced in the long term. In addition, the steel and aluminium road components can be directly recycled in the automotive industry; on the other hand, the financial gain could also be used to invest in the expansion of necessary infrastructure components for C2X communication.
Augmented Reality
The requirement for a digital traffic system, in which it takes over the entire traffic management, must continue to be the correct spatial mapping. In order for this to be possible via a head-up display as a communication medium, the display must be completed by an additional technology or type of display. A virtual ‘augmentation’ of reality creates the necessary display concept from the driver’s point of view.
With an Augmented Reality Head-up Display, digital elements appear at the optically proper position. This augmentation is generated by camera and radar data from the vehicle sensors, taking into account vehicle dynamics values and using digital map data and GPS positioning to create a model of the real world from the driver’s perspective.* The improved perception of traffic-relevant information enables the driver to capture the driving situation more quickly. A decisive factor in terms of comfort and safety.
This can be confirmed by a study evaluating the effectiveness of augmented reality applications in improving driving safety in elderly people who have a higher risk of accidents due to impairments in their perception. The conclusion of the tests conducted is that Augmented Reality applications used in vehicles improve the road safety of elderly people and do not have any negative impact on the various driving tasks.
The AR-HUD is the next step (…) into a holistic display and operating system for growing requirements. The AR-HUD function is creating a real dialog between the driver and vehicle. — Eelco Spoelder, Continental
Alternative solution for older vehicles
Despite the visionary communication concept and the latest technology required for it, the traffic system should continue to function universally for all road users and vehicles in the future. Upcoming new vehicles will meet the requirements in the coming years; however, the technical equipment of older vehicles does not allow digital communication and display of traffic guidance via an augmented reality head-up display without further ado.
Although the statistics* on passenger cars in Germany show that of the 45 million passenger cars registered, almost two thirds are no older than 9 years and only 1 percent are older than 30 years, an appropriate alternative solution is also needed for older vehicles if no categorical exclusion is to be permitted for the time being.
A ‘scrappage bonus 2.0’ is a comprehensive option that can be used to replace older vehicles with new ones and to provide holistic support for progress in individual transport. However, this does not solve the problem one hundred percent, since it cannot be assumed that every car will be replaced by a new one. Classic cars, for example, are a valuable historical resource for which an alternative must nevertheless be created.
Augmented Reality Glasses for Retrofitting
A conceivable solution results from the strong development in the areas of mixed reality. It can be assumed that augmented reality glasses (smart glasses) will become smaller, more powerful and cheaper within the next few years. In this way it is possible to use it as an alternative for older vehicles without AR-HUDs. In combination with the retrofitting of small modules for transmitting and receiving for C2X communication, older vehicles can also be converted into cooperative means of transport within the intelligent transport system. Perhaps these glasses will even become contact lenses or virtual retinal displays in the future.
According to the AR glasses for car drivers, the visor of a motorcycle helmet can be used to display the digital traffic guidance.
Advantages of the Intelligent Transport System
The much-needed holistic increase in efficiency in individual road transport can be achieved in the future through an intelligently connected transport system and its digitalization. A logical side effect is the enhanced comfort for the driver. With the use of state-of-the-art technical systems for connecting the vehicle with its surroundings and the visualization respectively communication via an AR-HUD, the driver experiences a certain broadening of his horizon. Traffic situations are identified at an early stage and even before entering the real field of vision. The term ‘anticipatory driving’ takes on a completely new dimension.
Last but not least, a dynamic adaptation of traffic management contributes to general safety. This can already be seen in today’s road control systems, which can drastically reduce the accident rate at critical points.* This interacts with an increase in the traffic flow, since the emergence of critical situations is reduced. Fewer accidents mean less congestion.
A quarter of traffic jams on German highways are caused by accidents.
Environmental compatibility
After all, traffic flow optimization has a positive effect on the environment. Since traffic jams and slow-moving traffic are less frequent, braking and acceleration processes can be reduced. During these phases, a vehicle’s fuel consumption and therefore its carbon dioxide emissions are the highest. Although this is not the case for electric cars, as long as they receive most of their electricity from a socket, power plants are indirectly responsible for CO² emissions. According to calculations*, the mobility-related emission is still about half that of vehicles with combustion engines.
Since the energy consumption of electric drives is equally high during start-up, there is another surplus for battery-operated cars in addition to better environmental compatibility: the increase in driving range.
Communication
With the direct connectivity of all parties and components involved in road traffic (C2X), the technical foundation has been laid for the digitalization of the traffic system. The windscreen (AR-HUD) is the optimal medium for displaying traffic guidance.
Not only to achieve the desired increase in efficiency, but also to ensure adequate communication of traffic management, a conceptual revision and adaptation for digital communication is required. In the conception and development, it was ensured that the advantages gained from digitalization would be utilized and that traffic management might not necessarily be transferred identically into the digital domain. It was also important to achieve further improvements in terms of safety, driving comfort and the environment and to rethink traffic management accordingly.
As much as necessary — as little as possible
At the same time, the aim was to avoid excessive digital noise. On the one hand, this is achieved by the optical superimposition of reality, in which a fusion between digital and real takes place and the digital can thus be subtly integrated into the real world. The viewer perceives the digital augmentation as less or not disturbing. At the same time, with the removal of all physical traffic signs, the global reduction of traffic management elements shall be digitally achieved as well, with the intention to reduce traffic management to a minimum.
Everything that is displayed on the windshield must have a legitimate reason for existence. Superfluous information or decorations overload the field of vision of the real environment and distract from the important information as well as the driving itself.*
Road Markings
The most basic element in the road traffic system will continue to be a core component in the future: The road marking.
As lane identification, it makes an essential contribution to traffic guidance and provides safe and unambiguous orientation. In addition, road markings are considered important traffic signals.
In digital form, they are always recognisable under all conditions and increase road safety, especially in poor visibility conditions. Lines will play an even more guiding role.
Individual
As with analog, a white marking (yellow on a snow-covered road or a very light road) creates the greatest possible contrast to the dark road surface, which continues to appear — in digital form — on the road. Although these follow similar guidelines as before, they have new properties.
Road markings are now limited to individually relevant lines while displayed, which means that they play a significant role in reducing visual information. In concrete terms, this means that the driver does not see any markings other than those that are important to him — those of his own lane, including secondary lanes on multi-lane roads and possible lanes at intersections. Markings of other lanes are not visible once they are no longer relevant. Any overlapping lane layouts, oncoming lane markings and other zones not intended for the driver will no longer be visible. Traffic guidance based on lane markings appears to be much more focused and thus allows better orientation.
The head-up display shows the driver only relevant road markings.
In addition to the idea of stronger guidance, the concept pursues the idea of using solid lines more frequently. In this way, the lines should consistently signal the demarcation from oncoming traffic. Dashed lines are used exclusively for marking alternative lanes on multi-lane roads or when there are turning possibilities.
Adaptable and reactive
Thanks to digitalization, there are completely new possibilities in dynamic adaptation. Starting with construction sites, the temporary yellow road markings (in Germany) are no longer necessary to overrule the white ones as they can simply be changed. A further advantage arises from the fact that in these usually more demanding driving situations no additional strain on perception is required. Likewise, the shifting and changing of road markings allows an intelligent lane management. If spatially feasible, a traffic-related lane mapping from 2|1 to 1|2 can be applied in order to allow a higher road capacity in a certain direction.
However, it is also possible to intentionally respond to short-term situations. By wiggling around obstacles and hazards, lane markings guide the driver around them and at the same time visually draw his attention to the obstacle (e.g. a second row stopped vehicle). Another scenario is vehicle characteristics such as length or width. For trucks and buses with a larger turning radius, the lane can be adjusted to better guide the driver around a curve. In addition, a slightly narrower lane can be displayed in the case of very wide oncoming traffic, which increases the driver’s attention.
Overtaking
With the continuous usage of the solid boundary line to the opposite lane, a general overtaking prohibition on single lane roads is introduced at the same time. According to an ADAC study*, overtaking on country roads saves relatively less time. Given a total distance of twenty kilometres, it would save just one and a half minutes. This field experiment confirmed that overtaking manoeuvres can only be truly rewarding for trucks and convoys. In the end, the ADAC came to the conclusion that overtaking usually does not save time and on the other hand increases the risk of accidents. On rural roads, overtaking is the second biggest cause of fatal accidents, alongside getting off the road. A stronger ban on overtaking can therefore be used as a legitimate way of preventing traffic accidents caused by overtaking manoeuvres.
But there must also be exceptions for this. For example, the overtaking of tractors must be allowed. This possibility is implemented as follows: In the case of obstacles or vehicles with a significantly reduced speed, which has a negative effect on the traffic flow, the driver can announce the wish to overtake by using the turn signal. If the oncoming lane is clear and the risk is low, the traffic system sends a signal back to the vehicle, which temporarily changes the lane marking to a dotted line and informs the driver of the permitted and safe overtaking.
Navigation
Map data on digital devices has become an important part of our development of mobility nowadays. With the use of navigation systems, physical street signs are rarely used. They are even used more often on well known routes or even daily rides. The advantage is that they provide information about the current traffic flow and can therefore recommend helpful route suggestions to the driver even for short distances.
Connected driving enables even more effective navigation by accessing comprehensive traffic data. Digital routing will therefore become even more important in the future.
Active and passive navigation
In addition to the active, visible navigation, a new feature allows a constant, passive navigation that runs in the background if the driver has not selected a route guidance on purpose. This passive variant automatically recognises typical destinations (e.g. home or work) and switches on automatically if there are delays on the chosen route. The driver can thereby rely on always being on the fastest route even when navigation is not visible.
Integration of regulatory parameters
Traffic regulations are directly integrated into navigation through communication between the vehicle and infrastructure or the digital traffic system. The integration of vehicle prohibitions and restrictions now has a direct influence on the route, depending on vehicle characteristics such as weight, height and width. As a result, forbidden roads are included in the route calculation.
When passing intersections, the road is visually highlighted in addition to the re-colored road markings.
Quality of information
The use of the windshield as a medium to display information offers the possibility of a much more intuitive navigation with the help of Augmented Reality than it is possible with existing systems. Similar to what we have seen for years in video games, the directions can be optically projected directly onto the road with an AR-HUD. Thanks to this way of displaying, it is no longer necessary to cognitively align the digital display with the real environment. This is the clearest and easiest to understand method of visual navigation.
Since a more complex traffic situation exists in real life driving — unlike on racetracks of racing games — no extra lines should be added that make it any harder to identify. If the routing is active, a color transformation of the digital road markings takes place. Green-blue lines then mark the route. The driver will remain guided between markings only. Through the adaptive use of existing road markings, a gentle but clear communication of the route is achieved. Particularly while no changes of direction are possible, an unobtrusive navigation is very pleasant for the driver. Bei anstehendem Richtungswechsel oder benötigter intensiveren Führung wird für diesen Streckenabschnitt zusätzlich die gesamte Fahrspur markiert, sodass verstärkt Aufmerksamkeit auf die Navigation gelenkt wird. If a further prior signal is required due to the situation, the display is supplemented by a direction arrow indicating the distance to the intersection. Optionally, each driver can activate the voice output as desired.
In contrast to simple road markings, the navigation line is not visually limited by other road users, but virtually overlays them. When selecting the color, particular consideration was given to a bright color as well as to contrast with the surroundings and other colors used (white and red). A green tint also implies correctness.
Right-of-Way Regulation
In road traffic, priority must be given at intersections and junctions. Thereby it must be clearly recognizable for all road users whether the right of way or the obligation to wait applies.
The digital redesign will bring about a decisive change in the right-of-way, which was previously controlled by traffic lights, traffic signs, road markings or right-to-left regulation. An intelligent right of way regulation will be primarily responsible for increasing traffic efficiency.
Enabled by transmitting vehicle position and route data to the traffic system, signal timings can now be made more efficient. They are no longer timed or controlled by local sensors, but are now directly dependent on all traffic. This reduces the frequency of waiting and, above all, the total waiting time on each trip.
Redesign of light signals
In the future, a virtual red wall is intended to serve as a universal stop signal. It will not only be assigned concretely for lanes, but also individually for road users, and its optical reference will simultaneously act as a stop line. A certain degree of transparency continues to ensure a view of the traffic situation. Red is retained as the learned signal color; from a psychological point of view, the stop signal is intensified with the help of the virtual wall — because nobody wants to drive a car against a wall.
As with today’s level crossings, drivers are allowed to move when nothing is displayed. In contrast to the red ‘wall’ (negative signal) it symbolizes an ‘open road’ (positive signal).
The red marking signals ‘give way’ to the driver.
Due to the individual allocation, the display of the yellow light period is also omitted; road users receive the ‘red light’ early enough and with sufficient distance to the stop position. The announcement of the change of a signal period is no longer necessary. In addition, a situation-dependent positioning takes place: If the situation so requires, the virtual wall can be flexibly moved forward to make it easier for any turning traffic to pass through.
Traffic-dependent signal period
The Intelligent Transport System can completely control the right of way with the exact data on the position, as well as the lateral and longitudinal direction of each road user. The uniform virtual right-of-way control is used at every intersection and communicates a positive or negative signal to the driver at all times. Especially at low traffic times and on roads with little traffic, this enables a constant flow of traffic; unnecessary delays and thus also CO² pollution are avoided. Road users do not need to stop to see the traffic and decide whether they are allowed to drive, but always receive the signal to go when the situation permits.
For road safety, the overall use of ‘light signals’ also represents a considerable advantage. It prevents human error and leaves no room for overlooking oncoming vehicles.
An important infrastructural element in road traffic is the roundabout. The dynamic right-of-way control also offers an improvement to this. For example, the circuit can prioritize if necessary and at the same time allow a higher number of vehicles to pass from a certain direction. On the other hand, convoys can also be interrupted to allow a more even traffic flow.
Turn signal
Connected driving brings a further benefit with regard to the interaction of the driver. The dynamic right-of-way control is enhanced by the integration of the turn indicators of road users. This enables the individual stop signal to cooperate with the turn signal and output a positive or negative signal depending on the traffic. Similar to today’s green arrow (in Germany), for example, right turns can be permitted if there is no traffic coming from the left. However, a crucial difference also favors the maintenance of the traffic flow: In contrast to turning right after stopping and as long as no one is obstructed or endangered, the precise signaling makes it possible to turn right without stopping. So anyone who flashes in time is rewarded.
All in all, C2X communication in combination with right-of-way regulation can be used to enormously increase efficiency in individual transport.
Parking lots and private areas
Certain traffic areas such as parking lots or private areas can be exempt from digital traffic control and are defined as such in the system. In these cases, a simple right-before-left control is sufficient. For communication with the driver, a corresponding message appears when entering and during traffic within these areas.
Countdown
Eine Anzeige der noch verbleibenden Zeit von Wartephasen einzuführen ist denkbar; allerdings auch fraglich und sollte durch Studien untersucht werden, bevor eine globale Einführung vorgenommen wird.
The interconnection of certain Audi models with traffic light periods in Las Vegas is being promoted by the German automobile manufacturer by optimizing traffic flow, saving time and protecting the environment. For the driver, a situation-related adaptation of his driving style should lead to a more relaxed locomotion. It remains to be seen, whether the traffic light information will really make people more relaxed or even lead to a risk of driving off too early.
With regard to the Intelligent Transport System, the question arises, if it is necessary to display a countdown at all with this optimized traffic management. The road user should be able to build confidence in this system and develop an awareness for the efficiency of the right-of-way regulation. An implementation at turn-ins in order to control the timing of acceleration should nevertheless be tested.
Prohibition of Traffic
Among prohibitions in traffic regulations, entry restrictions are an indispensable information.
Even in a future scenario in which every road user navigates in the traffic system according to the recommended route, the driver must have the right to move freely and off the designated way. For this reason, the prohibition on entering a road must remain to be indicated.
The signalling of a traffic prohibition will ensure significantly fewer wrong drivers thanks to precise (AR) and clear (HUD) communication.
First and foremost, false entries can be prevented by the intensified use of the solid line (road marking). The reduction of the visual noise of traffic signs also has a supporting effect. If it is also necessary to make the display more intensive, a solid red line is drawn to indicate this. Since the display is individually assigned by the traffic system, there is only one way of communication instead of different signs.
The solid red line marks the prohibition of entering.
Adaptive warning
A link with the drivers’ interaction can alert the traffic system to potential misconduct when flashing or steering in the wrong direction. Whenever it appears necessary in advance, the red line is reinforced by a virtual red wall — for example at motorway entrances and exits. The HUD will then also display a warning message about a wrong entrance. The latter serves to differentiate between a prohibition of traffic and a right-of-way regulation.
The driver receives a more prominent warning of the traffic prohibition.
If a road user enters the road despite a signalled prohibition, an acoustic warning sounds. In such cases, connected vehicle components should be able to be controlled by the traffic system so that a vehicle automatically comes to a standstill after a few meters in the wrong direction and its continuation in the wrong direction is blocked.
Speed Limit
In order to ensure safe travel in road transport, certain regulations on the maximum permitted speed apply on road sections. These speed limits are primarily designed to ensure road safety. In addition to local restrictions, they are often linked to other conditions. Additional signs indicate alternative regulations due to time or weather conditions. Furthermore, speed requirements can be used in order to protect the environment or reduce noise.
With a dynamic speed limit, the Intelligent Transport System can also have a direct influence on efficiency in the future. The flow of traffic can be better controlled by more intelligent linking to current traffic-relevant data.
Dynamic speed limitation
Unlike static traffic signs, digital communication allows permanent visibility and flexible adaptation of speed limits. In addition to the standard speed limit, which is designed for ideal conditions, the complex interaction of various factors results in variable regulation possibilities for different conditions:
- Traffic-related adjustment caused by heavier traffic, obstacles or construction sites.
- Weather-related adjustment due to poor road conditions or reduced visibility.
- Time-bound adjustment in favor of the environment, safety (e.g. school time) or noise protection.
- Vehicle-specific adjustment for certain types of vehicles (trucks, buses, cars with trailers, etc.).
Synchronized traffic lights
To maintain the traffic flow as well as possible, which at the same time reduces the environmental impact, a cooperation between right-of-way regulation and the speed indication makes sense. In the head-up display, the indication of a progression speed or coordination speed should also force the driver to reduce the speed. The maximum speed limit remains unaffected; in the case of a reliable calculation, only a recommendation of the optimum speed range is communicated so that the next intersection or turn can be passed without stopping.
Speedometer integration
A further improvement regarding the perception is achieved with the visual correlation to the driving speed. In combination with a graphical presentation, the quality of information is also improved. Humans can more easily see areas and shapes in relation to each other than to compare two numerical values with each other. Humans can more easily see areas and shapes in relation to each other than to compare two numerical values with each other. This also makes it easier to compare the traveling speed with the speed limit if they are graphically connected. The cognitive load is lower and reduces the mental effort of the driver again.
Numerical figures cannot be completely resolved due to their exactness, but are no longer used in the form of a scale, but exclusively for the indication of the travelling speed and the speed limit. To avoid flickering and a too fast changing of digits, the frequency is lowered. Although the dynamic speed regulation allows finer scaling digitally, this makes little sense with specific numbers due to poor differentiation and would be counterproductive for simplifying traffic management.
Peripheral vision
In contrast to the spatial display (augmented reality), all speed-relevant information is moved to the lower projection area of the windshield. The display is positioned in such a way that the view on the traffic situation is not impaired. This makes peripheral vision an important aspect of the design.
With his gaze focused most of the time on the road, the driver perceives certain visual impressions in different ways. As long as he does not explicitly focus the speed indication, the numbers cannot be read by the human eye. While the central field of view can detect a high degree of detail, the peripheral field of vision is blurred, but perceives simple objects more quickly.* This had an effect on the design and is reflected in the use of the most basic forms. Since this area also reacts more sensitively to movement — even in the dark — the display elements are not used statically, but deliberately complement the driver’s interaction with animations.
The choice of colors is based on bright colors with high contrast, so that the information on the head-up display can be read even when out of focus. The correlation of one’s own speed with the speed limit and progression speed can therefore be determined to a greater extent by the color. Since the peripheral field of vision — unlike the central area — is connected to the part of the brain that is amongst other things responsible for (subconscious) decisions*, an appropriate coloring can influence instinctive reactions.
Shape and color support the visualization of speed-relevant information and enable easier differentiation. This is less relevant for the accurate local projection of information, since it appears in direct correlation with the real world, integrates easily into the natural viewing directions when driving, and also does not represent textual information.
Interaction
The display, which consists of only two respectively three important speed data, primarily combines the own, current speed and the speed limit. The driver’s focus is therefore on the reference of these two points. Apart from the possible progression speed, no further indications are necessary; a scale is therefore not displayed. Both indicators (dots) move from/to the mutual central axis and move equally towards/away from the x-axis. A visually connected gap expresses the content-related link.
If the driver exceeds the speed limit, the two dots move in opposite directions. However, the space in between is red when it is exceeded and fills a larger area with increasing speed. At the same time, the driver receives a warning in relation to the exceeded speed, which first gently and gradually alerts him to his violation. In this way, a certain necessary tolerance is given. This means that the driver is not intrusively alerted at the slightest exceeding, but receives an appropriate escalation of the optical warning.
Regardless of whether the driver is below or above the speed limit, the display always visually pulls him towards the centre, the perfect speed. Instead of feeling the urge to fill up an incomplete bar (psychological effect), the overlapping of both dots should be understood as a ‘goal’.
Visualization of the progression speed
An exception to visual centering is the progression speed. It is displayed when available and extends the display by a green area. This area is not numbered with an exact value, but is displayed as a range at which the driver should travel. If the speed indicator is within the green area, the value of the current speed takes over the color as long as it is within this range.
Change of the speed limit
If there is a change in the speed limit, the driver is made aware of it both by the normal adjustment of the display and by an additional animation of the indicator. The red dot expands into an area for a short time.
Scaling
The maximum width of the speed display (e.g. reached at standstill) is equally limited in favor of simplification and legibility for all speed settings.
Another characteristic is the non-linear scaling. As it moves away from the reference point, the speed limit, it continues to grow exponentially. On the one hand, this supports the ascending warning of exceeding the speed limit; on the other hand, it reduces the horizontal movement of the indicators in the normal speed range close to the limit.
Intelligent speed assistant
Today’s technology makes it possible for vehicles to automatically adapt to the speed of the vehicle in front. This so-called automatic distance control (ADR) is to be assigned as part of the Adaptive Cruise Control (ACC).
The digital communication of the traffic regulation now allows an adaptive adjustment to the speed regulation. Such a function would not accelerate the vehicle beyond the maximum permitted speed. Diese Sperre ließe sich durch kurzes loslassen und umgehendes treten des Gaspedals zwischenzeitlich aufheben. The surplus for the driver is the simplification of his driving task, which is reduced in terms of speed. Illegal exceeding of the speed limit is avoided when the speed lock is switched on.
Cruise control
Progression speed is a good option for another pairing with the speed assistant. When cruise control is activated, the vehicle automatically adopts the recommended speed, if available.
On the way to autonomous driving, the digital communication of speed specifications represents an important step. This is also an enormous advantage for Assisted Driving.
Dangers
Besides its control regulations, every traffic system has to warn road users of immediate and possible dangers. Different road signs communicate specific warnings by using symbols.
On the one hand, the digitalization of the transport system and the connection of vehicles will make it possible to warn more effectively of certain hazardous situations; on the other hand, vehicle sensors will make a major contribution to safety.
More relevant and precise warnings resensitize road users and make the road transport system a safer place.
Reliable information on dangers is provided with the integration and cooperation of various data sources. Warnings thus become more relevant and are only displayed depending on the situation. Communication with the vehicle or the driver is presented in different ways in order to enable appropriate communication.
Integration
The most subtle type of warning is integrated into the existing traffic routing. Dangerous routes are generally avoided by appropriate navigation. If the accident risk on a route is temporarily higher, this is included in the calculation. The digital, always clearly visible road markings also act as an indication of obstacles. The dynamic speed limit takes weather and road conditions into account, so these warnings are also integrated. Due to this integration of dangers, many warnings are no longer compensated to communicate explicitly.
Highlighting
Often there are unpredictable dangers that can only be detected by vehicle cameras. By connecting with vehicles in front and exchanging camera data, such dangers can be better anticipated. Even areas not visible from a personal perspective become visible thanks to connectivity with other vehicles. The vehicle can therefore alert the driver of the possible danger at an early stage. These mostly moving objects, such as parked vehicles, tail ends of traffic jams or playing children, require a special warning.
The Augmented Reality Head-up Display makes it possible to visually highlight the imminent danger precisely. An intensive reddish tint draws the necessary attention.
Hint
Moreover, symbols remain a suitable way of drawing attention to hazards that cannot be integrated or adequately highlighted visually (e.g. slope). They are digitally shown above the speed bar, where they are instantly visible. There is also feedback in the steering wheel (vibration) for more serious hazards, and an acoustic signal for the most serious hazards.
Case Study
System Failure
Because of the indirect positive signalling (by not showing a virtual red wall), this would theoretically mean that in the event of a technical failure of the right-of-way regulation, the road would be open to every motorist at the same time. In the event of a system failure that is not recognized as such, a traffic chaos would be inevitable.
However, the decentralized digital traffic management system makes a failure an extremely unlikely scenario. As vehicles also communicate with each other independently at a certain distance (C2C), they are able to control the right-of-way on their own and are not reliant on a central control system. Although the control centre can manage the entire traffic more comprehensively, in an emergency the vehicles can take over. Compared to urban areas, the right-of-way regulation is also organized in this way in rural areas with less well-developed infrastructure for C2I communication.
Display units can also be affected by a failure. But this is not a problem either, because the functionality is constantly checked. If there is a malfunction, the ignition of the engine is blocked. If there is a defect while driving, the driver receives the message with a prompt to stop the vehicle immediately at a safe place. At the same time, other road users are automatically notified of the breakdown.
On Foot
The focus of this concept for an intelligent transport system is the perspective of the vehicle. For a successful implementation there are of course further challenges to be overcome which have not been addressed in this paper. Nevertheless, a brief outlook on cooperation with pedestrians in this transport system will be provided.
Existing pedestrian traffic lights and crosswalks would absolutely continue to be usable with this communication concept. Connected light signal systems for pedestrians can also communicate with vehicles and ensure that roads can be crossed safely on foot. People on crosswalks are detected by cameras and transmit the stop signal to the vehicle.
A more forward-looking solution connects pedestrians individually with the traffic system. For this purpose, mobile devices are recommended, which everyone nowadays carries with them. In combination with the intelligent traffic management, the possibility arises for people to cross the road at almost any point. To do this, the pedestrian could stop facing the road and wait for a short signal, e.g. to his smartphone, which gives him permission to cross the road safely.
No matter how mobility will evolve in the future, the idea for an intelligent transport system is not a one-way street and can be used cooperatively with other means of transport.
Résumé
In the next few years, our road traffic will probably be subject to greater changes than before. The topics of efficiency, safety, comfort and the environment are important for all parties involved. In order to live up to this aspiration, new innovative concepts are needed in all domains.
Automobile manufacturers made significant progress in recent years and are progressively driving the world market forward with technical developments. It is now time for transport systems to catch up and contribute to improving road transport. The comprehensive connectivity and digitalization of traffic management is the initial and necessary step into a future in which we will experience the new mobility.
Necessity is the mother of invention. — Plato
With this thesis a way for intelligent traffic systems is presented, which examines the perspective of the vehicle and its driver more precisely. At the same time, the idea of a digital communication of traffic guidance represents an important basis for autonomous driving.
If you’ve read the whole article, I’ll buy you a beer. ;)
The Bachelor thesis was finished in January 2017.
Supervised by Professor wolfgang gauss.
