DE102008023704A1 - Traffic adaptive assistance system controlling method for vehicle, involves accelerating vehicle in operating mode i.e. pickup mode, up to synchronization distance, which is greater than predetermined target place distance - Google Patents

Abstract

The method involves producing acceleration or deceleration of a vehicle by a traffic adaptive assistance system depending on speed of the vehicle and/or an ahead driving vehicle. The assistance system is operated in one or multiple operating modes depending on a traffic phase e.g. free traffic, prevailing at a vehicle position. The vehicle is accelerated in the operating mode i.e. pickup mode, up to synchronization distance, which is greater than a predetermined target place distance during each vehicle speed. Independent claims are also included for the following: (1) a computer program for implementing a method for controlling a traffic adaptive assistance system of a vehicle (2) a computer program product for implementing a method for controlling a traffic adaptive assistance system of a vehicle.

Description

The The invention relates to a method for controlling a traffic adaptive Assistance system of a vehicle according to the preamble of claim 1.

Such methods are described by the applicant in the DE 10308256 A1 . DE 102005033495 A1 . DE 102005017559 A1 and DE 102005017560 A1 proposed.

One particularly comfortable for the driver Assistance system usually results when the Reaction of assistance system (ie acceleration or deceleration of the vehicle) to the difference between an actual time interval and a target time interval or the difference between your own Speed and the speed of a preceding vehicle very slow (that is, small acceleration or deceleration values) he follows. However, this leads to security reasons a usually relatively large distance to the vehicle in front is provided, whereby other vehicles easily shear and so can disturb the driver. Farther has shown that a succession of vehicles with such "slow" Assistance systems may be unstable.

In known theories of traffic it was assumed that for a modeling of the traffic a theoretical fundamental diagram, in which a certain traffic flow belongs to a traffic density, can be applied, as in 1 to the state of the art with F = free traffic and C = traffic jam is shown.

For a traffic-adaptive assistance system ACC, this means that, for a vehicle speed v, the assistance system ACC is to aim for a target location distance d _soll to the vehicle in front, as shown in FIG 2 to the prior art illustrated by a distance-speed diagram and in the DE 10308256 A1 and in the DE 102005033495 A1 is described.

In these cases, if the actual local distance d is greater than the target local distance d _soll , an assistance system ACC can not distinguish between situations where catch-up is necessary and situations where no catch-up is required, as in 3 to the prior art with reference to a distance-speed diagram is shown in more detail.

In traffic-adaptive assistance systems with a control of a target local distance d _, a vehicle in front (see FIG 2 ), this leads to a compromise between dynamic behavior of the ACC adaptive assistance system in catching up the preceding vehicle and comfortable driving in which the catching-up of the preceding vehicle is not necessary, whereby both the catching-up of the preceding vehicle is not as dynamic as the comfortable driving is not are comfortable as a driver would drive himself. This can lead to dissatisfaction with control and / or regulating functions, in particular a distance control of the assistance system.

Of the The invention is therefore based on the object, a method of control indicate a traffic adaptive assistance system of a vehicle, in which a very strong dynamic behavior of a traffic-adaptive Assistance system can be achieved.

The The object is achieved by the in the claim 1 specified characteristics solved.

advantageous Further developments of the invention are the subject of the dependent claims.

At the inventive method for controlling a traffic-adaptive assistance system of a vehicle, wherein the assistance system depending on speed and / or distance related Sizes of the vehicle and / or a preceding vehicle Vehicle an acceleration or a deceleration of the Vehicle causes and wherein the assistance system dependent from the prevailing at the vehicle position traffic phase, in particular a free traffic, a synchronized traffic or a moving jams, operated in one of several operating modes is, the vehicle according to the invention in a Operating mode "catch up" up to a predefinable synchronization distance, which increases at every vehicle speed is accelerated as a given target location distance. Such a new operating mode "catch up" with such a controllable Synchronization distance allows a very dynamic Assistance system, in which when catching up a driving ahead Vehicle a very comfortable ride can be achieved safely even if catching up the preceding vehicle or a deceleration of the vehicle is not required.

In A further development of the invention is for this purpose at actual location distances, which are smaller than the synchronization distance, the operation mode "Catch up" switched off. This is another conventional one comfortable operating mode can be switched on, creating an individual Adjustment of the distance and / or a dynamic behavior of the assistance system in different traffic phases, z. B. in free traffic, in the synchronized Traffic and / or in a moving traffic jam are possible.

Preferably In the "catch up" operating mode, the vehicle is moved to the synchronization distance operated with a maximum acceleration. This allows the Distance to the vehicle in front individually, quickly and safely be adapted so that no large distance to the preceding Vehicle is created and thus other vehicles can not einscheren. Thus, the ride comfort for the driver significantly improved.

embodiments The invention will be explained in more detail with reference to a drawing.

there demonstrate:

1 a traffic flow traffic density diagram of the prior art,

2 a distance-speed diagram of the prior art,

3 a distance-speed diagram of the prior art,

4 a traffic flow density diagram for a synchronized traffic with controllable synchronization distance,

5 a distance-speed diagram with a target pitch, and

6 to 9 various embodiments of a distance-speed diagram in the operating mode "catch-up".

each other corresponding parts are in all figures with the same reference numerals Mistake.

The basis of the 1 to 9 The invention described in more detail below is based on the so-called Three-phase theory according to BS Kerner, "The Physics of Traffic", Springer, Berlin, New York 2004 , The three-phase theory is based on the traffic flow traffic density diagram 1 The three-phase theory leads to results in traffic simulations, which differ qualitatively from the empirically observed results. In particular, it was shown by a model in the three-phase traffic theory that instead of the fundamental diagram after 1 a two-dimensional surface in the traffic flow traffic density level can be applied for possible target location distances in the homogeneous traffic flow in order to be able to explain empirical traffic data, as described in US Pat 4 is shown. In this case, the line F shows a free traffic, the line d _{synchronously} a synchronization distance as a target location distance and the dashed area a synchronized by means of an assistance system ACC traffic with a particular homogeneous traffic flow.

Based on the three-phase theory is the inventive Assistance system ACC described in more detail. In doing so, the Control of the vehicle by means of the Assitenzsystems ACC both adapted to current traffic and / or current events. Therefore, the assistance system ACC is also considered traffic- and / or event-oriented Assistance system referred to (or TPACC controller called briefly).

In operation, the vehicle is conventionally controlled and / or regulated on the basis of the three-phase theory on the basis of the assistance system ACC in such a way that d _is in a two-dimensional region with an infinitely many different actual spatial distances (dashed region in FIG 5 ), if there is no speed difference Δv to a preceding vehicle, no target local distance d _{should be} used and no acceleration a or deceleration of the vehicle in the longitudinal direction is taken into account, as exemplified in one of the applications DE 103 08 256 A1 . DE 102005017560 A1 . DE 102005017559 A1 or DE 102005033495 A1 is described in more detail, the content of which is hereby incorporated by reference.

The assistance system ACC according to the invention additionally takes into account the synchronization distance d in _synchronism , as it does in 4 using a traffic flow traffic density diagram of the three-phase Ver The theory of traffic is described.

The invention is based on the core that if overtaking of the preceding vehicle is not possible or not desired, the driver is not to the target location distance d _should , but is accelerated _{synchronously} until reaching the synchronization distance d, as exemplified in the 6 is shown in more detail by means of a distance-speed diagram.

In other words, by means of the traffic-adaptive assistance system ACC, the vehicle is controlled such that it does not d _to the preceding vehicle to the predetermined target Ortabstand but catching d _{in synchronism} with the predetermined synchronization interval. In this case, the synchronization distance d _is selected _{synchronously} such that it is greater than the target local distance d _soll at each vehicle speed v.

requirement for such a synchronized operation of the vehicle is that the assistance system ACC speed and / or distance-related Size of the own vehicle and / or the preceding vehicle Vehicle supplied and / or determined by this. In the process, the vehicle is activated by means of the assistance system ACC of at least one or more of the speed and distance related Size an acceleration or deceleration the vehicle determined and executed.

So The assistance system ACC will depend on the vehicle position prevailing traffic phase, in particular free movement, a synchronized traffic or a moving congestion, operated, as exemplified in one of the above publications is explained in detail to the prior art.

For example, in certain value ranges of actual local distances d _ist for driving the vehicle by means of the assistance system ACC, no target local distance d _{soll is} used and no acceleration or deceleration of the vehicle in the longitudinal direction is provided if the difference between the actual time interval d _is ( or actual local distance) and a target time interval d _soll (or target location distance) is in a range of the time intervals (or location distances) for the synchronized traffic (see 5 ). For this purpose, speed-dependent limit values are specified, whereby the vehicle acceleration a (with -a = deceleration) in these ranges of values can be determined as follows and as in FIG DE 10308256 A1 described in more detail: a = k 1 Δv, [1] where Δv is the speed difference and k _{1 is} a predefinable constant.

The assistance system ACC also takes into account the traffic phase prevailing at the vehicle position and controls the vehicle depending on the traffic phase prevailing at the vehicle position, whereby when a phase transition occurs in the region of the vehicle position, ie when the traffic phase prevailing in the area of the vehicle position changes to another traffic phase , the assistance system ACC is switched to another operating mode, as in the DE 102005017559 A1 is described in more detail.

"Catching" in the inventive mode of operation can, moreover, the resume acceleration rate a _catch be weighted, if the difference distance .DELTA.d is greater than zero, wherein the difference distance .DELTA.d is determined from the difference from the actual Ortabstand _is d and destination Ortabstand d _should according to: Δd> 0 [2] _Is .DELTA.d = d - d _to [3] _to d = speed-dependent target Ortabstand (indicated by the driver).

The catch-up acceleration a _{catch up} is then determined as follows: a catch up = k 2 Δd, if Δd> 0 [4] with k ₂ = specifiable speed-dependent constant.

The vehicle _acceleration a is then made up using the weighted catch- _{up acceleration} a and the operating _acceleration a _{modus_j} is determined as follows: a = (1 - h) a modusj + ha catch up [5] with a _{modus_j} = operating _acceleration (or deceleration) in another operating mode "j" (j = 1, 2, 3, ...) or in other modes of operation and h = weighting factor.

According to the invention an acceleration of the vehicle in the operating mode "catching up" is only until the synchronization distance d _{in synchronism} according to 6 executed, wherein the synchronization distance d _{synchronously} at each vehicle speed v is greater than the target location distance d _soll . This means that at all _is actual Ortabständen d, which are smaller than the distance d synchronization _synchronism, the operation mode "catching up" is completely turned off.

For this purpose, the determination of the vehicle acceleration a according to equation [5] is changed and adapted as follows: a = (1 - hg catch up ) a modus_j + hg catch up a catch up [6] with h = weighting factor, g _{catch up} = net catching distance.

The associated distance-speed diagram is in 7 shown in more detail, where: G catch up = 1 if d is > d synchronous and [7] G catch up = 0 if d is ≤ d syncrhon , and for both [8] d synchronous > d should , [9]

Furthermore, in the "catch-up" operating mode, the vehicle is operated _{synchronously} with a maximum acceleration a _max until the synchronization distance d is reached. As a result, a maximum possible dynamics of the vehicle is achieved, so that larger distances to the vehicle in front are safely avoided. For this purpose, the vehicle acceleration a according to equation [6] is adjusted accordingly with: a catch up = a Max if d is > d synchronous , [10]

In a development of the invention may further at actual Ortabständen _is d, the d _{synchronization} between the synchronization distance and a safety distance d _safe (= hatched area in 7 ), one or more different comfortable modes of operation are used to accelerate or decelerate the vehicle longitudinally. This additionally achieves a comfortable ride of the vehicle in the traffic flow. In this case, at least in one of the operating modes, in particular in the operating mode "catch-up", the catch-up acceleration is determined according to equation [4].

In a further embodiment it is provided that the vehicle at a maximum possible acceleration a _max of the vehicle in accordance with equation [10] only to that of actual Ortabstand _d is operated, is not less than a predetermined maximum speed-dependent distance d (max) / a is like this on the distance-velocity diagram in 8th is shown closer, where: d is ≥ d (Max) a , and d (Max) a > d synchronous [11] and for equations [10] and [4]: a catch up = a Max if d is ≥ d (Max) a [12] and a catch up = k 2 Δd, if d is <d (Max) a , [13]

In the event that substantially equal speed differences Δv are given and an acceleration (deceleration) of the preceding vehicle takes place, the catch-up acceleration a _{catch-up is} weighted according to Equations [4] and [5] with the following weighting factor h:

9 shows a further embodiment in which, in the presence of actual local distances d _is in a range of: d (Max) synchronous > d is > d synchronous [15] the net Aufholabstand _catch g in formula (4) is a function of the actual Ortabstände _is d. If, for example, the net _catch-up distance g _{catch is changed} continuously between 1 and 0, if the actual position distance d _ist becomes smaller, the following applies: G catch up = 1, if d is ≥ d (Max) synchronous and [16] G catch up = 0, if d is ≤ d synchronous , [17]

Furthermore, the following parameters in the operating mode "catch up", such. As any other desired operating acceleration a _{modus_j} the resume acceleration rate a _catch and the net Aufholabstand g _{catch up} and the weighting factor h, in particular when determining the vehicle's acceleration a in the operating mode "catching" of various other functions such as the vehicle speed v, the speed difference .DELTA.V the acceleration (deceleration) of the preceding vehicle and the predetermined target time interval τ ^(set) dependent.

Alternatively or additionally, the following parameters, such as the synchronization distance d _synchronous , the maximum acceleration distance d (max) / a and the maximum synchronization distance d (max) / synchronous from predetermined other functions, such as the vehicle speed v, the speed difference .DELTA.v, the acceleration (deceleration ) of the preceding vehicle and the predetermined target time interval τ ^(set) .

The inventive method for controlling the vehicle is as a computer program in a control unit, in particular implemented and serves an assistance system ACC of a vehicle during operation of the control and / or regulation of the vehicle.

ACC

assistance system

d

distance

d _is

Actual distance

d _safe

safety distance

d _should

Target distance

d in _sync

synchronization distance

_{catch up}

Net Aufholabstand

d (max) / a

maximum speed-dependent distance

d (max) / synchronous

maximum synchronization distance

v

speed

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 10308256 A1 [0002, 0005, 0025, 0031]
• - DE 102005033495 A1 [0002, 0005, 0025]
• DE 102005017559 A1 [0002, 0025, 0032]
• - DE 102005017560 A1 [0002, 0025]

Cited non-patent literature

• - Three-phase theory according to BS Kerner, "The Physics of Traffic", Springer, Berlin, New York 2004 [0023]

Claims (13)

Method for controlling a traffic-adaptive assistance system (ACC) of a vehicle, wherein the assistance system (ACC) effects acceleration or deceleration of the vehicle as a function of speed and / or distance-related variables of the vehicle and / or of a preceding vehicle, the assistance system (ACC) Depending on the prevailing at the vehicle position traffic phase, in particular a free traffic, a synchronized traffic or a moving traffic jam, is operated in one of several operating modes, characterized in that the vehicle in a predetermined operating mode "catching up" only up to that synchronization distance ( d _synchronous ), which is greater than a predetermined target local distance (d _soll ) at each vehicle speed (v) is accelerated. A method according to claim 1, characterized in that at actual local distances (d _is ) which are smaller than the synchronization distance (d _synchronous ), the operating mode "catch-up" is turned off. A method according to claim 1 or 2, characterized in that in the operating mode "catch up" to the synchronization distance (d _{synchronously} ), the vehicle is operated with a maximum acceleration (a _max ). A method according to claim 2 or 3, characterized in that the vehicle in actual Ortabständen _(d) which is between the synchronization distance (d _synchronous) and a predefinable safety distance (d _safe) are, in at least one or more different modes of operation for acceleration or Delay is operated in the longitudinal direction. Method according to one of the preceding claims, characterized in that the vehicle with the maximum acceleration (a _max) only up to an actual Ortabstand _(d), is not less than a predetermined maximum speed-dependent distance d (max) / a, is operated. Method according to one of the preceding claims, characterized in that in the mode "catch up" the vehicle with a Aufholbeschleunigung (a _{catch up} ) according to: a catch up = k 2 · .DELTA.d is operated. Method according to one of the preceding claims, characterized in that the vehicle is operated at a speed (a) which takes into account an operating speed (a _{modus_j} ) in another operating mode and a weighting factor (h) for the catch-up acceleration (a _catch-up ) according to: a = (1 - h) · a modus_j + h · d catch up , Method according to one of the preceding claims, characterized in that the weighting factor (h) is determined at the same speed difference (Δv) and acceleration or deceleration of the preceding vehicle according to:

Method according to one of the preceding claims, characterized in that a net _catch-up interval (g _{catch up} ) in the region of the actual local distances (d (max) / synchronous> d _is > d _synchronous ) is a function of the actual local distances (d _ist ) , Method according to one of the preceding claims, that the operating _acceleration (a _modusj ), the catch-up _acceleration (a _{catch up} ), the net _catch-up distance (g _{catch up} ) and / or the weighting factor (h) of at least one parameter, in particular of the vehicle speed (v) , the speed difference (Δv), the acceleration or deceleration of the preceding vehicle and / or the predetermined target time interval (τ ^(set) ) are dependent. Method according to one of the preceding claims, characterized in that the synchronization distance (d _syncron ), the maximum speed-dependent distance (d (max) / a) and the maximum synchronization distance (d (max) / synchronous) of at least one parameter, in particular the vehicle speed (v), the speed difference (Δv), the acceleration (deceleration) of the preceding vehicle and the predetermined target time interval (τ ^(set) ) are dependent. Computer program with program code means to all Steps of a method according to one of claims 1 to 11 perform when the program is on a computer is performed. Computer program product with program code means, stored on a computer-readable medium are the method according to one of claims 1 to 11 if the computer program product is on a Computer is running.