FR2762906A1 - Vehicle guidance procedure has a connection to a remote database - Google Patents

Abstract

Procedure for guiding a motor vehicle starting from the vehicles coordinates, which are known from positioning equipment on board and from the destination chosen by the driver. The itinerary is calculated from the vehicle position, the destination, and in future versions, traffic conditions. The itinerary is calculated by a remote sever (2) and then transmitted to the vehicle, where the instructions are given to the driver in a vocal form. The vocal messages are stored on board in a dedicated memory (7) and the server (2) determines the points of the itinerary at which the stored messages are issued to the driver. The on board terminal (1) comprises means of geographical location (4) e.g. GPS, communication means to the server (9) and dedicated message memory (7). The server (2) comprises a processor (17) capable of recognising and interpreting the drivers spoken words, and a database of geographical data. A microprocessor (3) on board the vehicle controls the indication to the server of vehicle position.

Description

GUIDING METHOD AND DEVICE
MOTOR VEHICLE
The present invention relates to the field of aid to navigation of motor vehicles. More specifically, it relates to a method and a device for guiding a vehicle moving on the road network, based on the location of the vehicle, on the reception of traffic information, and on the operation of a database. geographic, for the development of an itinerary.

Known navigation aid systems generally make it possible to enter a destination address or the name of a service sought, to calculate a route according to various selected criteria, such as speed, choice of the most direct route or even the preferential use of certain traffic lanes (possibly taking into account the traffic situation), and to provide guidance in real time to the driver to his destination.

Some navigation aid systems, called autonomous, operate a geographic database on board the vehicle, while other systems depend on a road infrastructure, such as beacons located at the side of the track, or a specific server using a telecommunications network.

A disadvantage of autonomous navigation systems is that updating their database requires a change in their on-board support. On-board geographic data is therefore quickly out of date, in particular in certain rapidly evolving sectors.

This is the case in certain urban or industrial areas, where these systems are unfortunately unable to adapt in real time to changes in the network and road infrastructure.

In addition, autonomous systems require significant computing capacity, in particular to determine the best route based on the criteria chosen, to manage graphic display, and to synthesize voice messages. In addition, entering the destination is rarely easy, when it is carried out using the reduced keyboards offered on most devices. In general, these systems, the high cost of which depends both on the power of the computing means and on the quality of the graphic display means used, are far from meeting the expectations of users.

Dependent navigation systems of known type also require large computing capacities to perform route calculations on board the vehicle, and are provided with efficient display units, in order to present the calculated routes on screen. Furthermore, loading cartographic data through a telecommunications network is an expensive operation, due to the volume of data transmitted, and does not have the desired flexibility. While being dependent on outside operators, these systems therefore have high acquisition costs, to which are added specific operating costs.

The present invention aims to guide motor vehicles on routes established as a function of the actual state of the road network, while reducing the level of equipment and the operating costs imposed on users.

To this end, it proposes that the route be calculated by a server remote from the vehicle, and transmitted to the user in the form of voice messages.

According to the invention, the voice messages can be stored in a dedicated memory, on board the vehicle.

Preferably, the server determines the points of the route on which the messages stored in memory are restored to the user.

The invention however provides that the playback of messages is controlled on board the vehicle.

To establish this route, the server selects from a database a series of road sections, crossroads and directions to follow from these, and generates voice messages corresponding to each of these directions.

The invention also relates to a guide device. This device comprises a remote server of the vehicle in communication with an on-board terminal, which is provided with means of geographic location, and of means of communication with said server.

According to the invention, the server has a processing unit capable of recognizing the speech of the user, establishing a route, and generating voice messages, while the on-board terminal has a share of a microprocessor controlling in particular the indication of the location of the vehicle to the server, and the reproduction of the voice messages generated by the server, and on the other hand a memory unit allocated to the storage of the messages before their restitution.

The main advantage of this device is its very limited cost, owing to the fact that it uses the voice memory available on certain radiotelephones marketed, and that it is compatible with hands-free telephone installations, also remaining available for sharing on the vehicle, for other applications, such as emergency call systems.

The vocal reproduction of the guidance indications also saves a screen, and does not divert the driver's attention from the road scene.

According to a preferred embodiment of the invention, the server uses a geographic database allowing it to establish a route by selecting road sections, crossroads as well as directions to be followed from these, and it generates voice messages corresponding to each of these directions.

Other characteristics and advantages of the invention will appear clearly on reading the following description of a nonlimiting exemplary embodiment of the invention, in conjunction with the appended drawing, in which:
- the single figure is an architectural diagram
simplified device of the invention.

The device illustrated in Figure 1 is constituted by a terminal 1 on board the vehicle and by a server 2, remote from it. The terminal 1 comprises a microprocessor 3, a localization module 4, such as a GPS (Global Positioning System) receiver and two memory units 6, 7. The first unit 6 groups together the coordinates of particular crossroads, and the second unit 7 voice messages intended to be transmitted to the user during the passage of the vehicle through the crossroads in question.

A set of control buttons 8 interfaces the device with the user. The terminal 1 also comprises a mobile communication module 9, of the cellular radiotelephone type (possibly grouped materially with the second memory unit 7), and an antenna 11 remote from the other elements of the terminal, assembled in practice inside a common housing (not mentioned in the diagram). The terminal 1 can optionally comprise in addition a display screen 12 and a hands-free kit 13, including a microphone 14a (intended to facilitate the use of the radiotelephone during movement), and one or more speakers 14b, connected to this box.

The microprocessor 3 (which can be included in the localization module 4, in particular if the latter is a receiver
GPS), manages the communication of the terminal 1 with the server 2, and ensures the writing and the reading of the memory units 6, 7.

In the guidance phase, it calculates the position of the vehicle from the information received from the location module 4, and relates this position to the crossroads (corresponding to a route previously established by the server 2 and retained by the user), which are stored in the first memory unit 6. The microprocessor 3 also ensures the selection of the messages stored in the second unit 7 as a function of the proximity of the corresponding crossroads and their possible restitution to the user by reading and transmission inside. of the vehicle, through the speakers 14b. I1 also executes all the commands entered into the device by the user by means of the buttons 8, such as calling the server, sending and recalling voice messages stored in memory.

The server 2 comprises a fixed communication module 16 in connection with the mobile communication module 9, a calculation or processing unit 17, and a geographic database 18. The processing unit 17 in particular ensures recognition and interpretation of the words of the user, while unit 17 determines the optimal road route using the database 18, on the basis of the location and destination indications transmitted by the terminal 1. According to the invention, base 18 is made up of a directory of road sections and crossroads located by their geographic coordinates, and orientation indications at crossroads, corresponding if possible to existing signs on the ground.

In this database, the road network can be structured into a network of main roads, and a network of secondary roads, in order to introduce a distinction between the indications of directions provided to the user according to the type of road that 'he borrows. However, this provision does not present any character of obligation for the implementation of the invention.

The guidance proposed by the invention is preferably carried out in the following manner. The user initiates a call to the server 2 using a button on the interface 8 and interrogates it in natural language, once the communication has been established. The terminal 1 then indicates to the server 2, the position of the vehicle determined by the module 4, and the latter recognizes the speech of the user using a voice recognition device of known type, possibly assisted by an operator .

The server then calculates an optimal route on the road network, using a database, of the type mentioned above, possibly taking into account road information (traffic conditions, accidents, closed axes, etc ... ), according to criteria defined by the user. This route consists of a set of sections, crossroads, and directions to follow for each of them.

A series of voice messages is generated for these indications, using natural recorded and compressed sentences, or by artificial speech synthesis. Each intersection of the journey is identified by location coordinates (for example G.P.S coordinates, or obtained according to an equivalent tracking system). The voice messages, as well as the corresponding geographic coordinates, and their position in the memory unit 7 (or equivalent length of each message), are transmitted to the vehicle by the same means, through the fixed communication module 16 and the mobile communication module 9. Finally, these messages will be supplemented in certain cases by general information on the route, such as the overall journey time, or that of the main sections.

In accordance with the invention, the terminal 1 then loads the voice messages into the memory unit 7, as well as the geographical coordinates and the size of the voice messages into the Memory unit 6. This principle allows numerous variants of application without leaving within the scope of the invention, in particular the recall of terminal 1 by the server 2, to offer it new routes, in the event of an event modifying the traffic state, or the information of the server 2 by the terminal on the successive crossing of the crossroads of the route.

As indicated above, the invention finds a preferred, but not exclusive, application in the operation of a database structured in two levels, respectively defining a main road network and a secondary road network. When the crossroads listed in the base actually correspond to road nodes of a main network, the orientation messages on the latter can advantageously reproduce the signs present on the ground.

On the secondary network, the invention provides at least two possible guidance modes, respectively called increased guidance by street)> and compass guidance. According to the first, the coordinates of the vehicle are constantly compared with those of points stored in memory, so as to trigger (as on the main network), the emission of messages appropriate to the approach of the latter, anticipating the case if necessary, automatically group certain messages when the distance between two successive listed points is less than the accuracy of the localization module 4.

According to the second guidance mode provided for the secondary network, the messages may be limited to indicating a first intersection to be reached on the main network.

In all cases, the transmission of messages can be triggered or renewed by the user using his control buttons 8. Furthermore, the method of the invention does not exclude partial reproduction (for example distance and heading indications on the secondary network) or total messages in text or graphic form, on a screen such as that of a standard radiotelephone.

The implementation of the invention does not impose any particular structure on the audio messages. However, this should as far as possible be optimized, in order to limit the communication time. In this sense, provision can be made for a portion of the messages, corresponding to actions to be followed, to be sent to terminal 1 only once at the start of the call, instructing the terminal to recompose this message later using the addresses. stored in unit 6.

According to the invention, the messages are normally sent in voice form. However, certain messages containing digital data, such as the position of the vehicle, or information intended to be displayed on the radiotelephone screen independently of the voice announcements, can be transmitted using techniques provided by the GSM standard, such as SMS (Short Message
Service). In addition, DTMF (Dual
Tone Multiple Frequency), which allows, among other things, coding of telephone keys, can be used, by coding certain data in parallel (or overlay) with voice messages. These two techniques are not exclusive, it is possible to increase the reliability of the transmission of messages by using simultaneously SMS messages, and DTMF coding.

Finally, it should be noted that certain practical difficulties encountered in receiving voice messages on the terminal can be overcome by judiciously using these two techniques, in particular by transmitting data to the terminal in the form of SMS messages, and by sending '' a DTMF code by the terminal, to request the transmission of voice messages.

Claims (12)

CLAIMS form of voice messages. distant from the vehicle, and transmitted to the user under in that the route is calculated by a server (2) of the vehicle, and of the desired destination, characterized and the calculation of a route according to the on-board location, the entry of a destination by the user, of the vehicle using road network location means based on geographic location [1] Method for guiding a motor vehicle on the  vehicle, in a dedicated memory unit (7).  in that voice messages are stored on board the [2] Guidance method according to claim 1, characterized  the memory unit (7) are returned to the user.  of the route on which the messages stored in  characterized in that the server (2) determines the points [3] Guidance method according to claim 1 or 2,  checked in the vehicle.  characterized in that the reproduction of the messages is [4] Guidance method according to claim 1 or 2,  these directions.  generates voice messages corresponding to each of  and directions to follow from them, and  selects a series of road sections, crossroads  previous, characterized in that the server (2) [5] Guidance method according to one of claims  on board the vehicle.  messages, are loaded in a terminal (1)  of selected junctions, and the size  in that voice messages, contact details [6] Guidance method according to claim 5, characterized  crossroads of the main network.  limit to indicate the direction to follow to reach a  a secondary network on which messages can be  provided correspond to the road network signs, and  main traffic on which the indications  characterized in that the server (2) distinguishes a network [7] Guidance method according to claim 5 or 6,  partially recomposed on board the vehicle.  previous, characterized in that the messages are [8] Guidance method according to one of claims  SMS.  are exchanged in the form of messages  previous, characterized in that some data [9] Guidance method according to one of claims  DTMF.  are transmitted using analog encoding  previous, characterized in that some data [10] Guidance method according to one of claims  messages before their restitution.  a memory unit (7) assigned to the storage of these  the user of the voice messages generated by it, and  vehicle to the server (2), as well as the return to  controlling in particular the indication of the location of the  that the terminal (1) has a microprocessor (3)  route, and generate voice messages, and in that  to interpret the speech of the user, to establish a  processing (17) capable of recognizing and  characterized in that the server (2) has a unit  communication means (9) with the server (2),  (1) provided with means of geographic location (4), and  vehicle in communication with an on-board terminal  road network comprising a server (2) remote from [11] Device for guiding a motor vehicle on the  corresponding to each of these orientations.  these, and generates voice messages  crossroads as well as directions to follow from  route by selecting road sections,  geographic data (18) enabling it to establish a  characterized in that the server (2) operates a database of [12] Guide device according to claim 11,