System for determining traffic information

Abstract

A system determines traffic information. The system contains a terminal having a position determination device for determining a position of the vehicle, a storage device for storing reference positions defined by location coordinates, and a processor which works together with the position determining device and the storage device. The processor compares a specific position of the vehicle with stored reference positions to determine whether the vehicle has passed a reference position. A reference position is defined by a safety line extending through the location coordinates thereof. The processor also determines whether the vehicle has traversed a safety line and evaluates the traversing of a determined safety line as the vehicle passes the reference position defined by the safety line. Therefore, the system can determine a position in a simple and reliable manner, including in an inner-city road network.

Claims

1. A system for determining traffic information, the system comprising: a terminal carried along in a vehicle, said terminal having: a position determination facility for determining a vehicle position and a driving direction of the vehicle in a road network; a memory for storing reference positions defined by location coordinates; and a processing facility which works together with said position determination facility and said memory, said processing facility comparing a specific position of the vehicle with stored reference positions for determining whether the vehicle has passed one of the reference positions, a reference position is defined by a safety line running through the location coordinates thereof, wherein the safety line is defined by a reference driving direction for vehicles assigned to the reference position of a carriageway and runs at right angles to this, wherein said processing facility being embodied to determine whether the vehicle has traversed the safety line, to compare a driving direction of the vehicle determined with a traversing of a determined safety line with stored reference driving directions and to evaluate the traversing of the determined safety line as the vehicle passes the reference position defined by the safety line, wherein a passing of the reference position is excluded if the safety line was traversed by the vehicle in a driving direction which deviates from the reference driving direction.

2. The system according to claim 1, wherein the safety line is defined by a safety line length assigned to the reference position of the carriageway.

3. The system according to claim 1, wherein said terminal has a signaling facility which works together with said processing facility, said signaling facility is embodied, after defining that the vehicle has passed the reference position, to output a message having the location coordinates, a passing time instant and identification data of said terminal.

4. The system according to claim 3, further comprising a traffic control center assigned to the road network for further processing messages, wherein said terminal has a communication facility for a wireless transmission of messages output to said traffic control center.

5. The system according to claim 4, wherein the reference positions stored in said memory are assigned message attributes containing at least one of a type, an address, a content or a cycle of a message to be output.

6. The system according to claim 5, wherein the reference positions can be added or deleted by said traffic control center by means of said communication facility in said memory of said terminal or defining features and message attributes thereof can be changed.

7. The system according to claim 4, wherein said traffic control center is: a toll control center for collecting road use charges in the road network, wherein chargeable stretches of road are assigned the reference positions; or a traffic management control center for determining travel times in the road network, wherein end points of stretches of road are assigned the reference positions; or a control center for emergency vehicles for their prioritization to traffic signal-control nodal points of the road network, wherein accesses to the nodal points are assigned the reference positions; or a control center for local public transport vehicles for activating passenger information facilities, wherein connecting roads between stations of the vehicle are assigned the reference positions.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIG. 1 is an illustration showing a section of road with a defined reference point according to the invention; and

(2) FIG. 2 is a block diagram of a terminal for a system for determining traffic information.

DESCRIPTION OF THE INVENTION

(3) According to FIGS. 1 and 2, a system for determining traffic information comprises a terminal 1 carried along in a vehicle V and a traffic control center 2 assigned to the road network used by the vehicle V. The terminal 1 has a facility 11 for determining a vehicle position P of the vehicle V in the road network, for instance on the carriageway S shown. A driving direction D of the vehicle V is produced from the connecting vector of two vehicle positions P determined one after the other.

(4) The terminal 1 has a storage facility 12, in which reference positions R of points in the road network which are relevant to traffic information are stored. The reference position R is defined by a straight safety line L, which runs through the location coordinates of the reference position R and at right angles to the carriageway S. It has a safety line length LL, which protrudes beyond the carriageway S on both sides. Moreover, the safety line L is defined by a reference driving direction LD assigned to the reference position R, the reference driving direction representing a direction of movement predetermined by the traffic routing to the reference position R and being disposed at right angles to the safety line L for instance.

(5) A processing facility 13 determines whether the vehicle V traverses the safety line L and at what traversing angle α the safety line L was traversed. To this end the specific vehicle positions P are compared with the position and length of the safety line L. In addition, when the safety line is traversed, the driving direction D is compared with the reference driving direction LD. If by complying with predeterminable comparison accuracies it is determined that the safety line L was traversed in the reference driving direction LD, the processing unit determines that the vehicle V has passed the reference position R.

(6) In this case, a signaling facility 14 of the terminal 1 outputs a message M relating to the location coordinates and time instant that the vehicle passed. If necessary, the message M still contains identification data of the terminal 1, so that a series of messages M can be assigned to the outputting terminal 1. The output message M is transmitted wirelessly to the traffic control center 2 for further processing by means of a communication facility 15 of the terminal 1. In the storage facility 12, specific message attributes can be assigned to the reference positions R, such as for instance the type and/or the addresses and/or the content and/or the cycle of a message M to be output. Conversely, reference positions R can be added or deleted in the storage facility 12 of the terminal 1 by the traffic control center 2 by means of the communication facility 15, or the defining features and message attributes thereof can be changed.

(7) The advantage of the inventive system consists in it being possible to perform a position determination by a mobile terminal 1 at predefined reference points R without using a digital road map by means of a definition of a reference object which is very simple to generate. The feature as a safety line L combined with the associated reference driving direction LD and safety line length LL allows for a more accurate and reliable detection of a defined reference position P being reached or passed, compared with previous methods. Here the actual location coordinate of the reference position R does not have to be reached exactly. Differently to interception circuits with an extended circular area, the reference driving direction LD on a safety line L is clear. The safety line length LL can be adjusted to the local conditions. The problem of overlapping adjacent reference objects is considerably reduced in safety lines by comparison with interception circuits. The position determination method also optimizes the temporal behavior in the terminal 1 when a reference position R is identified. A universally usable method is described by the use of additional message attributes for reference positions R, said method being suited both to use in a traffic control center 2 and also in the same or a further mobile terminal.

(8) Reference numeral 16 shows a passenger information facilities connected to and activated by the traffic control center 2