EP2335233B1 - Method and apparatus for determining a driving strategy - Google Patents

Abstract

A method for determining a driving strategy for a driver of a motor vehicle includes receiving local information about a plurality of other motor vehicles using a receiving device, wherein the plurality of other motor vehicles are ahead of the motor vehicle and are relevant to the traffic situation. The method further includes recording the local information using the receiving device and deriving driving information from the local information so as to provide a driving strategy in the form of at least one action recommendation for the driver, the at least one action recommendation including a recommended speed based on an average speed of the plurality of other motor vehicles and on a desired speed of the motor vehicle.

Description

The invention relates to a method for determining a driving strategy as information for the driver of a motor vehicle, in which, in particular, local information of further, in particular preceding motor vehicles is detected by means of a receiving device and information derived therefrom for the motor vehicle driver is provided. Furthermore, the invention relates to a device for carrying out the method.

Such communication systems for direct information exchange between motor vehicles already form a communication platform for a wide range of information services and traffic telematics applications. In particular, various proposals for optimizing the traffic flow due to stationary, but in particular also determined by motor vehicle data of the traffic situation are already known from the prior art.

Road traffic is one of the most important complex systems of our modern world. The complexity levels that arise here range from individual actions of individual motor vehicle drivers to local phenomena such as density fluctuations and traffic congestion, the choice of route and time of the road users, local and temporal traffic patterns and transregional traffic flows to long-term traffic development and traffic regulation.

Special challenges arise from the complex interaction of countless road users. The result is complicated and difficult-to-control phenomena that affect the flow of traffic in a very undesirable way. An example This is a traffic jam, which comes at high vehicle densities due to various causes the stop-and-go driving. The result is reduced traffic flow, growing travel times, nervousness of drivers and increased risk of accidents.

These issues are of particular acute importance due to the associated increased energy consumption and the resulting environmental impact.

Communication systems between multiple vehicles are designed as an ad hoc network. They are therefore not dependent on any pre-installed network infrastructure and in particular allow the exchange of data in the local or regional environment of a motor vehicle.

In addition to typical Internet and telematics applications, these wireless networks will support traffic-related applications, such as dangerous weather and cooperative driver assistance systems. Communication across multiple automobiles opens up a new dimension to the delivery of telematics applications by making data available from systems of preceding vehicles, such as the vehicle's driving situation sensed by sensors or data from camera or radar systems.

From the DE 10 2007 053 738 A1 In general, a vehicle-to-vehicle communication device for communication between automobiles is known in which the transmitting motor vehicle not only communicates its own data, but also information about adjacent motor vehicles.

Furthermore, the describes US 2005/0225457 A1 a technique in which not only the positional information of a motor vehicle equipped with the communication device is transmitted, but also the position information of surrounding appropriately equipped motor vehicles picked up by a camera or the like.

The information is generally displayed by visualization on a display. For example, pictograms with an information content such as "congestion hazard" or "construction site" are used for this purpose. The DE 102 00 883 B4 shows a method for displaying information on a screen, for example, that of a navigation device in a motor vehicle.

In recent years, some approaches have been developed that put the individual driver at the center. These include so-called assistance systems, which should ensure increased ride comfort and increased safety. Examples include the cruise control system, also known as "cruise control". Recently, there are also advanced approaches, known as "Adaptive Cruise Control", which also take into account the driving behavior of the immediately preceding vehicle detected by the vehicle's own sensors.

So revealed the DE 103 49 434 A1 how such a distance and speed control can be brought into a different mode in stop-and-go situations so as not to jerk constantly and brake. Such methods are based on information that is determined by corresponding sensors of the motor vehicle, in particular at its own speed. An exchange of information between several vehicles is not provided.

According to the teaching of DE 10 2005 050 277 A1 Also, the behavior of a preceding vehicle is detected by sensors.

The DE 10 2007 037 329 A1 describes a method for determining a driving strategy in order to optimize the operating costs, in particular the fuel consumption. For this purpose, information can be detected by sensors of the motor vehicle and measures for improving the operating state can be displayed. The method is an optimization of various - presumed as expected - parameters that play a role in the choice of route.

The DE 101 30 768 C2 discloses a channel access method for ad hoc radio networks for the exchange of data between motor vehicles.

In addition, the reveals DE 197 50 942 A1 a method and a device for determining a driving strategy as information for the driver of a motor vehicle, wherein information of further motor vehicles detected by a receiving device and provided therefrom for the motor vehicle driver derived information as a signal for reducing the speed.

In addition, the concerns DE 100 29 816 A1 a driver-assisted assistance system for optimal driving. To calculate the driving recommendations, data for recording one's own driving situation and the preceding traffic situation are included of GPS data for determining the current location of the vehicle and including digital road maps for detecting the local road guidance and an output of computer-assisted determined driving recommendations to the calling system user considered.

Furthermore, technical devices on motorways and expressways, which are often referred to as traffic control systems, improve the traffic flow on one or more sections, nodes or in the entire network by means of collective influencing. In addition to improving the user's traffic quality and preventing unstable traffic conditions such as shockwaves and traffic jams, the traffic management system's task is to increase traffic safety by reducing the speed variance in the motor vehicle collective and optimizing the distribution of journeys to the available infrastructure. Stationary signals and traffic signs serve to implement the switched strategy into visual symbols for the motorists, for example to limit the speed.

The change systems used in today's practice for the traffic control have the disadvantage that they provide relatively nonspecific, therefore often unnecessary speed limits, which find little attention among road users. After all, they no longer fulfill their purpose in a traffic jam, because they no longer drive globally fast anyway; the time and energy consuming stop-and-go waves in the traffic jam are not avoided.

One might think, in addition to the indication of the risk of stowage, also to provide such information, which includes information about the exact extension and the speed of the vehicles therein. This way of providing information overwhelms the road user and ultimately does not lead to the right conclusions. Rather, the road user is additionally distracted from the traffic.

In practice, therefore, such information is often completely ignored due to its comparatively abstract and often unavailable to the road user information content after recent initial interest.

Another approach is the so-called electronic drawbar, with which motor vehicles are to be forced to form exactly synchronized convoys at a relatively high speed and a small distance. In this way could fast overtaking maneuvers for passenger cars in better-served roads and due to the lower air resistance of the individual motor vehicles, a reduction in fuel consumption and thus the environmental impact can be achieved.

The electronically coupled motor vehicle is oriented with the aid of a computer-controlled image processing system on the preceding motor vehicle. A video camera detects a specific pattern at the rear of the front vehicle. The computer calculates direction, distance and relative speed and adjusts the following vehicle precisely. Optionally, infrared light sources can generate the pattern, which increases the effort, but also the evaluation reliability. Aside from the high demands placed on the technical safety of such systems, the problem of liability for damage caused by faults also proves to be disadvantageous.

For macroscopic approaches, it is generally true that they are too bulky and too slow to influence the traffic dynamics in a timely manner: a congestion can only be detected once it has reached a certain size. Added to this is the inaccuracy of the traffic detection by the limited stationary and with large inaccuracies afflicted measuring points. Even the emerging replacement of traffic by navigation devices only affects the choice of route, especially a congestion avoidance, but not on the behavior of the traffic in traffic jams themselves.

The invention has for its object to provide a way to reduce energy consumption at the same time as the travel times and the risk of accidents and thereby improve the flow of traffic.

This object is achieved by a method according to the features of claim 1. The further embodiment of the invention can be found in the dependent claims.

According to the invention, therefore, a method for determining a driving strategy is provided as information for the driver of a motor vehicle, in which information of further motor vehicles is detected by means of a receiving device and information derived therefrom for the motor vehicle driver is provided, wherein the provision of information comprises at least one recommended action for a recommended speed is determined from the average speed of several vehicles driving ahead and relevant to the traffic and the desired speed of the motor vehicle. This is the first time the motor vehicle driver an individual recommendation provided for an optimal speed, which is not based on a general consideration of the traffic, but derived from the captured information of preceding vehicles. In contrast to stationary signal systems, a comprehensive acceptance of the respective motor vehicle driver is ensured due to the high accuracy of this instruction, as is already approximately the case with navigation systems today. In addition, there is a measurable and significant reduction in energy consumption when following the instruction. The motor vehicle driver thus recognizes the instruction as a real advantage for his driving behavior and will increasingly base his action on the positive experiences that are associated with it. In contrast to the car-to-car radio networks known hitherto, not only status data are transmitted, but concrete optimization suggestions derived therefrom, which offer the expected benefit to the motor vehicle driver if he follows them. As a result, the energy consumption is significantly reduced in a surprisingly simple manner and also improves the flow of traffic, at the same time the risk of accidents decreases. Additionally or alternatively, the derived information can be transmitted to an assistance system, for example an adaptive cruise control.

bestimmt, mit
v_emp = empfohlene Geschwindigkeit
v_des = Wunschgeschwindigkeit, insbesondere in Abhängigkeit von physikalischen Aspekten und Sicherheitsaspekten
v_avg = Durchschnittsgeschwindigkeit vorausfahrender Kraftfahrzeuge
λ = Ausgleichsparameter.The recommended speed according to the invention is v _emp according to the formula: $${\mathrm{v}}_{\mathrm{emp}}\mathrm{=}\min \left({\mathrm{v}}_{\mathrm{of}}\mathrm{.}\mathrm{\lambda }{\mathrm{v}}_{\mathrm{of}}\mathrm{+}\left(\mathrm{1}\mathrm{-}\mathrm{\lambda }\right){\mathrm{v}}_{\mathrm{avg}}\right)$$

certainly, with
v _emp = recommended speed
v _des = desired speed, in particular depending on physical aspects and safety aspects
v _avg = average speed of preceding vehicles
λ = compensation parameter.

In principle, the method already proves to be helpful with a single preceding vehicle. On the other hand, it is even more advantageous if the information is recorded by a plurality of motor vehicles, in particular at least five preceding vehicles, so as to avoid possible congestion. Even with a small number of detected motor vehicles, the inventive method leads to a more comfortable and stress-free driving without unnecessary braking and acceleration operations.

The compensation parameter could be determined dynamically based on acquired information, in particular on the basis of empirical values. However, it has proved particularly useful proved, if a value between 0 and 1, but in particular between 1/2 to 2/3 is determined as compensation parameter λ.

A particularly advantageous embodiment of the method according to the invention is achieved in that the optimum speed is determined from measured values of the speed of the own motor vehicle as well as the received information of the speed of several preceding motor vehicles. In this case, the risk of stowage is reduced by the motor vehicle driver being presented with a speed recommendation at a reduced speed, which already takes into account the time change of the traffic situation, in particular of the vehicles in front, with regard to their density, average speed or local distribution. Compared to a static traffic control system, the deviation of the proposed driving speed from the self-desired is lower.

It proves to be particularly promising if the transmitted information at least the position and speed of a respective preceding motor vehicle include so as to draw conclusions on the change of the future traffic situation on the one hand, and the corresponding own optimal speed on the other.

One could come up with the idea that one of the average speed of several preceding vehicles corresponding speed would be recommended. In contrast, in practice, however, it is particularly advantageous if the recommended speed lies between the instantaneous speed of the motor vehicle and the average speed of several vehicles driving ahead and relevant to the traffic, so that in theory the own motor vehicle approaches the vehicles in front. However, the delayed approach leads to a partial reduction of the motor vehicle density of the preceding vehicles and thus to a resolution of already existing areas of viscous traffic. Of course, the speed recommendation determining factor in turn may be dependent on the average speed.

In principle, the method according to the invention works without a stationary infrastructure, because all relevant information is captured by the motor vehicles involved. A meaningful supplement is then realized, if in addition also information of stationary or local sources of information is recorded, so also further available knowledge about the traffic situation in the calculation of the optimal speed to be able to involve. In particular, motor vehicles that are not equipped with the requirements for car-to-car information transmission can also be detected in this way.

It is also particularly practical if the determined recommended speed is visualized on a display and thus can be read directly by the driver as an amount. In a meaningful way, the deviation of the optimal speed can be visualized by the current speed, in particular a multi-colored Dar position facilitates readability. Furthermore, additional or alternative acoustic indications are conceivable. Alternatively, the thus determined recommended speed can also be transferred to an assistance system.

In addition, it is particularly promising if, in addition, the fluctuations in the speed of preceding vehicles are determined in order to derive qualitative information about the traffic situation of the detected motor vehicles. Possible traffic risks can thus be recognized early on, as a result of conspicuous signals.

The information provided to the motor vehicle driver can be transmitted according to a particularly meaningful modification to other motor vehicles, so that not only the current, but also the expected traffic situation can be taken into account.

Furthermore, it proves to be particularly expedient if the information, in particular derived information, are transmitted by means of a transmission unit to other motor vehicles, so that the motor vehicles located in the vicinity can also incorporate the derived information into their own information provision.

Furthermore, a recognizable for other road users notice of active participation in the process may be provided. For this purpose, devices are suitable which not only provide information about the corresponding vehicle equipment by means of visually perceptible markings or instructions, but also about the current active participation in the system.

The method is not limited to motor vehicles. Rather, the method can also be used in the optimization of traffic flows of cyclists, pedestrians including Athletes in the exercise of various sports or even used by watercraft.

Claims (11)

1. Method for determining a driving strategy for the driver of a motor vehicle, in which information on further motor vehicles is acquired by means of a receiving device and information derived therefrom for the driver of the motor vehicle is prepared, wherein the preparation of the information comprises at least one recommendation of action for a recommended velocity, characterized in that the recommended velocity (v_rec) is determined from the instantaneous velocity of the motor vehicle and the average velocity of a plurality of motor vehicles which are travelling ahead and are relevant for the events on the road, according to the formula: $${\mathrm{v}}_{\mathrm{rec}}\mathrm{=}\min \left({\mathrm{v}}_{\mathrm{des}}\mathrm{,}\mathrm{\lambda }{\mathrm{v}}_{\mathrm{des}}\mathrm{+}\left(\mathrm{1}\mathrm{-}\mathrm{\lambda }\right){\mathrm{v}}_{\mathrm{avg}}\right)$$

   

   
   where
   v_rec = recommended velocity;
   v_des = desired velocity;
   v_avg = average velocity of vehicles travelling ahead;
   λ = compensation parameter.
2. Method according to Claim 1, characterized in that the recommended velocity is determined from measured values of the velocity of the motor vehicle and received velocity information on a plurality of motor vehicles travelling ahead.
3. Method according to Claim 1 or 2, characterized in that the transmitted information comprises at least the position and the velocity of a motor vehicle travelling ahead.
4. Method according to at least one of the preceding claims, characterized in that the information is acquired on a plurality of motor vehicles, in particular at least five motor vehicles, travelling ahead.
5. Method according to at least one of the preceding claims, characterized in that a value of between 0 and 1, but in particular between 1/2 and 2/3, is determined as a compensation parameter λ.
6. Method according to at least one of the preceding claims, characterized in that information on stationary or fixed information sources is also additionally acquired.
7. Method according to at least one of the preceding claims, characterized in that the recommended velocity which is determined is displayed on a display.
8. Method according to at least one of the preceding claims, characterized in that the recommended velocity which is determined is fed to an assistance system, in particular an adaptive cruise control system.
9. Method according to at least one of the preceding claims, characterized in that the fluctuations in the velocity of motor vehicles travelling ahead are additionally taken into account.
10. Method according to at least one of the preceding claims, characterized in that the information, in particular derived information, is transmitted to other motor vehicles by means of a transmitter unit.
11. An apparatus which is intended for determining a driving strategy as information for the driver of a motor vehicle in order to carry out the method according to at least one of the preceding claims, in which information on further motor vehicles is acquired by means of a receiver device and information which is derived therefrom for the driver of the motor vehicle is prepared by means of an output unit, wherein the preparation of the information comprises at least a visual or acoustic recommendation of action for a recommended velocity, characterized in that
    there are means for determining the recommended velocity (v_rec) from the instantaneous velocity of the motor vehicle and the average velocity of a plurality of motor vehicles which are travelling ahead and are relevant for the events on the road according to the formula: $${\mathrm{v}}_{\mathrm{rec}}\mathrm{=}\min \left({\mathrm{v}}_{\mathrm{des}}\mathrm{,}\mathrm{\lambda }{\mathrm{v}}_{\mathrm{des}}\mathrm{+}\left(\mathrm{1}\mathrm{-}\mathrm{\lambda }\right){\mathrm{v}}_{\mathrm{avg}}\right)$$

    

    
    where
    v_rec = recommended velocity;
    v_des = desired velocity;
    v_avg = average velocity of vehicles travelling ahead;
    λ = compensation parameter.