WO2008044087A1

WO2008044087A1 - Vehicle sharing system and method for a fleet of vehicles

Info

Publication number: WO2008044087A1
Application number: PCT/IB2006/003231
Authority: WO
Inventors: Loïc VINCENT; Guillaume Chevret
Original assignee: Renault Trucks
Priority date: 2006-10-11
Filing date: 2006-10-11
Publication date: 2008-04-17

Abstract

This system is for sharing a fleet (F) of vehicles (1,1') between several users (D1, D2). It comprises an access control unit (101) installed onboard each vehicle (1,1'), a communication module (107), associated to each unit and installed on board the same vehicle, and a customer identification device (200) for each user (D1, D2). This system comprises a database (401) including identification data for each registered user. The communication module (107) is adapted to receive, from a remotely located server (400) having access to the database, identification data relating to at least a driver (D1) authorised to access the vehicle (1) on which it is installed. The control unit (101) includes means to generate, on the basis of the data received by the communication module, at least a first access code to said vehicle and means to compare the first access code to a second code received (S4) from a customer identification device (200) and to grant or not access to said vehicle as a result of this comparison.

Description

VEHICLE SHARING SYSTEM AND METHOD FOR A FLEET OF VEHICLES

TECHNICAL FIELD OF THE INVENTION

This invention concerns a vehicle sharing system for a fleet of vehicles between several users, e.g. several drivers of a fleet of trucks. The invention also concerns a method for sharing vehicles between several users.

BACKGROUND OF THE INVENTION

Vehicle fleet management has become more and more important in the recent years since several users might be allowed to drive successively the same vehicle. This concerns in particular car rental companies who can install rental stations, as explained in US-B-6 850 153. In such a station, a user having an identification card must go to a kiosk where he or she enters some information which allow a central facility to determine whether or not a car is available for this user and, if such is the case, to grant access to this car for a predetermined time period, e.g. five minutes. In such a system, the user must come to a rental station to have access to a car and he or she must bring the car back to such a station at the end of the rental period. A kiosk must be provided in each place where a user is likely to rent a car, which induces high investment and maintenance costs. Moreover, every time a user needs to access a car, an authorisation must be obtained from the central facility, which might be lengthy. Such a known solution cannot be used for a fleet of vehicles which are supposed to be accessed in non-precisely located or non-predetermined places, like parking lots on highways, by drivers of the same truck company who share the same truck for a long distance trip or who work one after the other on the same truck.

SUMMARY OF THE INVENTION

The invention aims at providing a flexible vehicle sharing system which facilitates the use of a vehicle by different drivers, without having to install a kiosk and a station where vehicles have to be brought back at the end of a period of use.

To this purpose, the invention concerns a vehicle sharing system for a fleet of vehicles, between several users, this system comprising an access control unit installed onboard each vehicle, a communication module associated to each unit and installed onboard the same vehicle and a costumer identification device for each user. This system is characterised in that: it comprises a database including identification data for each registered user; - the communication module of a vehicle is adapted to receive, from a remotely located server having access to the database, identification data relating to at least one driver authorised to access the vehicle on which this module is installed;

- the control unit includes means to generate, on the basis of the data received by the communication module, at least a first access code to the vehicle and the control unit includes means to compare the first access code to a second access code received from a customer identification device and to grant or not access to the vehicle, as a result of this comparison. Thanks to the invention, an access code to each vehicle can be computed by a unit installed onboard this vehicle, this code depending actually on the identity of a user having access to this vehicle. Under such circumstances, a user having a customer identification device able to generate, upon request of the control unit installed onboard the vehicle, a second code which matches the first access code, can access the vehicle without having to go through a kiosk or any equivalent data entry installation. As soon as the vehicle has received, thanks to its communication module, the information data relating to an authorised driver, it does not need to be brought back to any station or particular location in order to be accessible for this authorised user. In the case a truck is left by one driver on an particular parking lot, this truck can be accessed by any other driver of the same company provided that the corresponding data has been sent beforehand to the control unit of the truck, wherever this truck is parked, as long as the communication module can be reached by a signal sent from the server. For example, in case a driver is sick or unable to drive his truck, once his company is aware of the situation, the company can give access to the same truck for a second driver who has his personal customer identification device with him and does not need to go to the headquarter of the company to pick up keys or an access card, since his personal customer identification device will be recognised as valid for access to the truck by the unit installed onboard the truck, once the unit has generated a first access code on the basis of the identification data relating to this second driver. Moreover, once the identification data has been received by the communication module, verification of the capability of one user to access a truck is made by the control unit without having to access a central facility. In the sense of the present invention, a keyless access system to a vehicle is a system where a user has a customer identification device in the form of a remote control device which can be actuated by the user, e.g. by pressing a button, to unlock a door of the vehicle. A passive keyless access system is a system where the user has a customer identification device which can exchange information with an onboard control unit without being manually actuated by the user. This invention applies both to keyless and passive keyless access systems. It also applies to passive go systems where a customer identification device is used, without needing to be manually actuated, in order to allow a user to start the engine of a vehicle and drive it. According to further aspects of the invention, this system might incorporate one or several of the following features:

- Communication between the server and the module takes place via a long distance wireless telecommunication network

- Communication between the control unit and the customer identification device is encrypted

- Communication between the server and the module is encrypted

- The customer identification device includes means to generate the second code, on the basis of identification data concerning a user it is allotted to.

The invention also concerns a method which can be implemented with the above mentioned system and which comprises at least the following steps:

- a) information data relating to at least one user having authorised access to a vehicle is sent wirelessly to a communication module connected to an access control unit installed onboard said vehicle.

- b) the control unit generates a first access code on the basis of the data received.

- c) when an attempt is made to access and/or start the vehicle, the unit requests a second code from a customer identification device and compares this second code to the first code and - d) depending on the result of the comparison step c), the control unit grants or not access to the vehicle.

Thanks to the method of the invention, one can verify the consistency of the data corresponding to the customer identification device of a user with the authorisation rules forwarded to the truck in the form of the identification data of the driver or drivers having access to a particular vehicle.

According to further aspects of the invention, this method might incorporate one or several of the following features:

- The method comprises the step of storing in a database identification data relating to all registered users, the data sent in step a) being sent by a server having access to this database

- Steps a) and b) are performed each time a new user is authorised to access vehicle, whereas steps c) and d) are performed each time an attempt is made to access and/or start the vehicle - In step c), comparison between said first and second codes is made on a part of these codes.

- When several users are authorised to access a vehicle, first access codes corresponding to each user are generated by the control unit and, during step d), comparison takes place between the second code received from a customer identification device and each first code, up to when one detects that the user corresponding to the device is an authorised user or up to when the second code has been unsuccessfully compared to all first codes.

- Alternatively, when several users are authorised to access a vehicle, a signal representative of a first code for each authorised user is sequentially sent to the customer identification device and comparison takes place between said first and second codes, up to when one detects that the user corresponding to said device is an authorised user or up to when representative signals corresponding to all authorised users have been sent unsuccessfully.

- In step b), the first code is computed by a function having the identification data as a variable.

- The second code provided by a customer identification device is generated by this customer identification device on the basis of identification data concerning a user to whom this device is allotted. - This second code can also be computed, by a function having the identification data as a variable.

- The same function can be used to generate the first and second codes on the basis of the identification data.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood on the basis of the following description which is given in correspondence with the annexed figures and as an illustrative example, without restricting the object of the invention. In the annexed figures:

- figure 1 is a schematic representation of a vehicle sharing system implementing the invention.

- figure 2 is a perspective view of a customer identification device belonging to the system of figure 1. - figure 3 is a schematic view of a passive keyless access control subsystem used with the system of figure 1.

- figure 4 is a block diagram of a first part of a method according to the invention and implemented with the system of figures 1 to 3.

- figure 5 is a block diagram of another part of the method and - figure 6 is a block diagram of another part of the method.

- figure 7 is a diagram similar to figure 4 for a second method according to the invention.

- figure 8 is a diagram similar to figure 5 for another part of the second method. - figure 9 is a diagram similar to figure 6 for another part of the second method.

- figure 10 is a view similar to figure 2 for a customer identification device corresponding to a second embodiment of the invention and

- figure 11 is a view similar to figure 2 for a customer identification device corresponding to a third embodiment of the invention. DETAILED DESCRIPTION OF SOME EMBODIMENTS Two trucks 1 and V belong to a fleet F of trucks managed by an administrator or fleet manager A. Several drivers can be authorised or not to drive each of the trucks 1 and 1 ', two drivers D₁ and D₂ being shown on figure 1 . Each truck 1 or 1' is provided with a keyless access system 100 to control access to its cabin 2 or 2' for a driver D₁ or D₂ having a customer identification device, hereafter "CID", 200. Each CID is a small dimension electronic device which is adapted to emit, when, receiving a challenge signal, a response signal comprising an alphanumerical identification sequence or code which is specific to each CID. System 100 of truck 1 is schematically shown on figure 3. System 100 includes a control unit 101 connected to an actuation switch 102A located near the handle 21 of the driver's door 22 of truck 1 , this switch being suitable to send to unit 101 a first signal Si when the handle is being touched or approached by a user.

Unit 101 is also connected to a low frequency antenna 103A located near or on the door 22. When unit 101 receives signal S-i, unit 101 computes, thanks to a microprocessor 1010, an alphanumerical sequence. Then, unit 101 sends to antenna 103A an actuation signal S₂ corresponding to this sequence. Then, antenna 103A sends a low frequency encrypted challenge signal S₃ which also corresponds to the computed sequence and which is supposed to be received by the CID 200 of a user. When authorised driver Di is near antenna 103A with his CID 200 in hand, in a pocket or in a bag, when this CID 200 receives signal S₃, it calculates a response signal S₄ which is sent as a high frequency encrypted radio signal and received by a high frequency antenna 104 connected to unit 101. Signal S₄ received by antenna 104 is then verified by microprocessor 1010 in unit 101 and, if signal S₄ is found to be consistent with the alphanumerical sequence already computed by microprocessor 1010, that is if that CID 200 permits access to cabin 2, unit 101 sends an actuation signal S₅ to an actuator 105A which mechanically unlocks the driver's door of cabin 2.

Unit 101 is also connected to an activation switch 102B, a low frequency antenna 103B and an actuator 105B located on the passenger side of cabin 2 and which are supposed to be used when the user wants to access this cabin by the passenger's side. According to an optional aspect of the invention, unit 101 is coupled to a passive go unit 1 11 which is capable of recognising CID 200 when this device is within cabin 2, in order to allow starting of the engine and driving of the truck, without having to use a key. According to an alternative embodiment, unit 111 might be integrated into unit 101.

Therefore, as explained here-above, once it is recognised by unit 101 , a CID

200 gives access to a truck without necessity for driver Di to register or declare himself as a user in a kiosk or any equivalent data entering station. In this sense, system 100 and CID 200 form together a passive keyless access system to truck 1. if unit 111 is provided, they form a passive keyless access and go system.

Each truck of the fleet is provided with a similar system 100.

In order to allow a dynamic and efficient driver's allocation to the trucks of fleet F, each unit 101 is also provided with a communication module 107 which is adapted to receive data from a satellite 300 which also communicates with a central server 400. Administrator A has a workstation 500 which gives him/her access to server 400. Server 400 includes a database 401 where one stores identification data relating to all registered and potential users Di, D₂, etc. of trucks 1 , 1 ' etc. These data might include, for each driver Di, D₂, his name, his first-name, his driver's licence number, his address, the list of countries where he is authorised to drive, etc. For each driver, one notes di a subset of the data relating to this driver. This subset is unique for each driver and is intended to be used in a telecommunication process, as explained here-after.

When administrator A considers that driver Di should have access to truck 1 , he retrieves subset di of the identification data relating to driver D₁, from database, 401 and sends it, via server 400 and as a part of a telecommunication signal S₆, to satellite 300. Satellite 300 resends signal S₆ as a redirected signal S'₆ which reaches module 107 wherever truck 1 is provided that truck 1 is in the zone covered by satellite 108 which can be as large as a substantial part of a continent.

Alternatively, signal S₆ can be sent to module 107 via a set of fixed antennas, one antenna being shown on figure 1 with reference 300'. Signal S₆ may then be redirected several times, as a signal S'_6l before reaching module 107.

Communication between server 400 and module 107 occurs through know techniques, e.g. mobile phone technology, as GSM, GPRS or UMTS, wireless network access technology, as WIFI or WIMAX, satellite phones or broadcasting technology. Since some trucks are already equipped with that kind of technology, the invention does not substantially increase their cost.

As shown on figure 4, administrator A allocates driver Di to truck 1 in a first step 1001 and the corresponding information is sent as signal S₆ and S'₆ to module 107 of truck 1 in another step 1002.

Subset di corresponds to the information data relating to driver Di sent from server 400 to module 107 by administrator A.

When it receives signal S'₆ in a further step 1003, module 107 forwards it to unit 101 , as an electrical signal S₇ representative of data di.Then microprocessor 1010 computes a first access code Ci with a function fi using information data d-i as a variable.

As an alternative, a microprocessor different from the one used to verify signal S₄ as mentioned here-above can be used to compute code C₁. However, it is more economical to use the same microprocessor 1010 for both operations. Computation of code C₁ takes place in a step 1004 which is followed by a step 1005 where code C-i is stored in a memory 1011 belonging to unit 101.

On the other hand, when a new driver is given access to at least one truck of fleet F, one allots him a CID which will be considered as personal, in so far as it is loaded with identification data d'i relating to this driver only, as shown with step 2001 on figure 5.

The information data d'-i relating to driver D₁ and loaded in his CID 200 might be similar or different from data d-t. In the present example, one considers that d'i is the same as d-i.

When data is loaded on CID 200, it is stored in a memory 201 1 belonging to this device.

As shown on figure 2, an easy way of loading information data d'-i relating to driver D-) into his CID 200 is to use his tachograph card 600, that is a card which a driver must always have with him when driving a truck and which is provided with a microchip 601 and electronic data storage means. The outer shell 202 of CID 200 is provided with a slot 2021 which constitutes an entry zone of a not further represented card reader. When data has been stored in memory 2011 at the end of step 2001 , tachograph card 600 can be pulled out of slot 2021 for further use.

As an alternative, as shown on figure 10, where only the outside parts of a CID 200 are represented, a CID 200 might be provided with a fingerprint reader cell 203 which allows identification of driver Di by applying one or several of his finger tips on this cell. In such a case, information data di sent by administrator A to unit 101 for a driver corresponds to the fingerprints of this driver.

As shown on figure 1 1 , where only the external parts of a CID 200 are represented, a CID might incorporate two electric connectors 204 which allow this

CID to be connected to an identification data storage means like a computer.

Moreover, CID 200 might be provided with a keyboard 205 which allows manual data entry.

Of course, for the sake of flexibility, a CID might incorporate several of the identification data loading means mentioned with reference to figures 2, 7 and 8 and other such means.

When information data d'-i has been loaded in CID 200, a microprocessor 2010 belonging to this CID computes in a further step 2002 an identification or second code C₂ as a function of data dV To compute second code C₂, one uses a second function f₂ which has data d'i as a variable.

In this embodiment, functions f-i and f₂ are the same, so that codes C₁ and C₂ are identical since data di and d'i are the same as considered here-above. However functions fi and f₂ may also be different.

Once code C₂ has been computed, it is stored in memory 2011 in a further step 2003 and remains accessible for future use by CID 200.

As shown on figure 6, when driver Di wants to enter truck 1 on the driver's side, he touches or approaches switch 102A in a first step 3001 , as explained here- above. After generation of the challenge sequence in step 3002, challenge signal S₃ is sent by antenna 103A in step 3003. The left column of figure 6 shows method steps which take place onboard truck 1 , thanks to unit 101 and the annexed equipments. The right column shows the method steps performed by CID 200.

When it receives signal S₃ in a further step 4004, CID 200 gets code C₂ from memory 201 1 and generates a response signal S₄ on the basis of code C₂. Then, it sends signal S₄ in a further step 4005. In fact, code C2 is sent as a part of signal S₄ Signal S₄ is received by antenna 104 in a further step 3006 and then forwarded to unit 101 where, in a further step 3007, first code Ci and second code C_2, transferred within signal S₄, are compared to each other.

If these two codes match, either because they are the same or because they are linked by a predetermined relationship, microprocessor 1010 considers that CID 200 belongs to an authorised user and sends, in step 3008, a signal S₅ to actuator 105A to open the door 22. If such is not the case, door 22 remains closed.

The vehicle sharing system of the invention comprises as many systems 100 as needed, as many CID 200 as needed, one or several satellites 300 or fixed antennas 300', a server 400 and a user interface like the workstation 500.

According to a further embodiment of the invention, computation of the second code C₂ in each CID 200 might be done from data ύ\ stored in memory 201 1 every time that this CID receives a challenge signal S₃ from the access system 100 of a truck, this code C₂ being then immediately forwarded to antenna 104 as signal S₄ or a part of this signal.

For the sake of safety, communication between server 400 and each module 107 is encrypted.

Thanks to the invention, it is possible to remotely grant access to truck 1 for driver D₁ without needing driver Di to meet administrator A or to come to the headquarter of the truck company once his CID 200 has been located with his personal data. For some specific users, like fleet manager A or a person in charge of maintenance, access can be given to all the trucks of fleet F.

Thanks to the invention, it is no more necessary to pair a vehicle with the or each corresponding access card at the end of the manufacturing process of the vehicle or during a maintenance operation, as this was the case for prior art systems.

For most drivers, and according to the habits of the profession, access can be given to one truck at a time, which allows the administrator or fleet manager A to follow precisely the matching between one driver and one truck, with a high security level. It is particularly useful to take into account the fact that a driver Di might be sick or unable to drive a truck on a predetermined date. In such a case, a second driver D₂ can drive the truck in place of the sick driver Di without having to even meet the first driver, in so far as the identification data of driver D₂ has been sent to truck 1 by server 400. One can also consider the case where a fleet manager grants access to a single truck for different drivers at a time. This allows the fleet manager to remotely anticipate and handle trucks and driver changes. In this case, when someone wants to enter the cabin, first codes Ci are sequentially generated by unit 101 for all authorised drivers and, for each code Ci sent, unit 101 compares the secondary code C₂ received from this person's CID (if any) to the corresponding first code stored in its memory 101 1. As soon as one comparison is positive, the corresponding door of the truck is open. If not, one goes to the end of the set of first codes and the comparison is found to be unsuccessful so that the door of the truck remains closed. With the invention, it is even possible for the fleet manager A to grant access to several trucks for a group of several drivers. Then the drivers of a group can organise their work between themselves.

A second method according to the invention is represented on figures 7 to 9. In this method, steps 1001 to 1003 of figure 7 are identical to the same steps in the first method. In step 1004, code Ci is computed by a function fi having di as a variable. Code Ci takes the form of two elementary codes Ei and F-i. These two codes are stored in a memory in step 1005.

On the other hand, as shown on figure 8, after identification data d't, which, in this embodiment, is the same as data di, has been loaded in a CID 200 in a first step 2001 , a second code C₂ is computed in a second step 2002. This second code takes the form of two elementary codes E₂ and F₂. This second code is computed on the basis of data d'₁ by a function f₂ which, in this example is the same as function f|. Therefore, in this case where data di and d'₁ are the same, elementary codes Ei and E₂ are the same, and elementary codes Fi and F₂ are the same. As shown on figure 9, when driver D₁ wants to enter truck 1 , he activates switch 102A in a first step 3001 as in the first method. In step 3002, a modified first code C'i is computed in unit 101 by a function g-i having elementary code Ei and a random number N as variables.

In step 3003, modified code C₁ is embedded into challenge signal S₃ which is sent by antenna 103A, in encrypted format, towards CID 200.

When it receives signal S₃, CID 200 accesses its memory where elementary codes E₂ and F₂ have been stored and, by a proper computation, CID 200 retrieves number N from code C'-|. Since, as mentioned here-above, elementary codes Ei and E₂ are identical, number N can be retrieved by CID 200 from code d by "subtracting" or otherwise reverse-calculating elementary code E₂ from code C₁. When number N is known, CID 200 computes a second modified code C₂ on the basis of a function g'₂ having elementary code F₂ and number N as variables. This takes place in a first step 4004 which is followed by a step 4005 where signal S₄ is sent to unit 1001 in encrypted format. C₂ is transferred to unit 101 via signal S₄ into which it is embodied. After it has been received in unit 101 in a first step 3006, signal S₄ is analysed and, since microprocessor 1010 knows number N, it is able to retrieve elementary code F₂ from modified second code C₂ transferred with signal S₄. It is then possible for microprocessor 1010 to compare elementary codes E₂ and F₂. If these codes are different, microprocessor 1010 considers that the answer of CID 200 is not valid and no access is given to truck 1. If elementary codes E₂ and F₂ are identical, access is given to truck 1 in a further step 3008.

In step 4004, modified code C₂ is generated on the basis of code C₂ so that the comparison which takes place in step 3007 is a comparison between parts of codes Ci and C₂ which allows to actually compare codes Ci and C₂.

Functions fy and f₂ might be different so that codes Ei and E₂, on the one hand, F₁ and F₂, on the other hand, might be different. In such a case, comparison step 3007 is adapted.

Of course, in step 3007, it would be equivalent that the unit 101 extracts from C₂ a number N', on the basis of F^ which is expected and checks that this number N' is the same as the number N which it has used to generate C'i in step 3002.

This second method is safer than the first method in so far as challenge signal S₃ is specific of each driver and includes a random number N, which means that signal S₃ is different each time it is sent. Signal S₄ is also different each time, since it includes number N.

When the fleet manager grants access to a single truck for different drivers at a time, steps 3002, 3003, 4004, 4005, 3006 and 3007 are performed successively for each driver. In other words, a first signal S3 is emitted on the basis of a random number and a first elementary code, specific of the first driver and computed by unit 101. If the answer received from CID 200 is consistent, then access is given to the truck. If not, another attempt is made to generate another challenge signal on the basis of information data corresponding to another driver. This proceeding goes on for all drivers.

According to a third method of the invention, the second access code C₂ corresponding to a driver can be permanently stored in a CID 200. In other words, this code is not computed within the CID but can be computed in an external device like a personal computer or a PDA and then stored within the CID without further modification. In such a case, database 400 includes, for each driver, some information with respect to the code stored in his CID. In case a driver is given access to a truck, this information is then sent to the truck, with a signal S₆ as explained here-above. In this case, for safety reasons, it is essential that communication between server 400 and module 107 is encrypted.

The advantages listed here-above for the first method are also valid for the second and third methods.

The invention has been described here-above with respect to a passive keyless access system. However, it may also be used with an "active" keyless access system where the user actuates his CID by pressing on a button, his CID being then usually called a "remote controller". The invention has been described here-above with respect to a passive keyless access system. However, it may also be used with a passive go system that is a system where a CID is used to allow a driver to start the engine of a vehicle and drive this vehicle after he has accessed to driver's seat.

LIST OF REFERENCES

1 Truck r Truck

2 Cabin

21 handle

22 driver's door

2' Cabin

100 system onboard a truck 101 control unit

1010 microprocessor

1011 memory 102A actuation switch 102B actuation switch 103A low frequency antenna

103B low frequency antenna 104 high frequency antenna 105A actuator 107 communication module 11 1 passive go unit

200 customer identification device or CID

2010 microprocessor 2011 memory

202 shell 2021 slot

203 fingerprint reader cell

204 connectors 205 keyboard

300 satellite 300' fixed antenna 400 server

401 database 500 workstation

600 tachograph card

601 microchip

1001 driver allocation step

1002 signal emission step 1003 signal reception step

1004 code generation step

1005 code storage step

2001 data loading step in CID 200

2002 code generation step in CID 200 2003 data storing step in CID 200

3001 actuation step of system 100

3002 challenge sequence generation step

3003 signal emission step 3006 signal reception step 3007 signal comparison step

3008 signal emission step

4004 response signal generation step in CID 200

4005 signal emission step by CID 200 A administrator / fleet manager

Ci first code

C'i modified first code

C₂ second code

C₂ modified second code

Di driver di information data d'i information data

D₂ driver

Ei elementary code

E₂ elementary code

Fi elementary code

F₂ elementary code fi function f₂ function

F fleet gi function

92 function

N random number

S₁ actuation signal

S₂ actuation signal

S₃ challenge signal

S₄ response signal

S₅ actuation signal

S₆ telecommunication signal

S'β redirected signal

S₇ electric signal

Claims

1. A vehicle sharing system for a fleet (F) of vehicles (1 ,1 '), between several users (Di, D₂), said system comprising an access control unit (101) installed onboard each vehicle (1 ,1 '), a communication module (107) associated to each unit and installed on board the same vehicle and a customer identification device (200) for each user (D-i, D₂) characterized in that:

- it comprises a database (401 ) including identification data . for each registered user

- said communication module (107) is adapted to receive, from a remotely located server (400) having access to said database (401), identification data (di) relating to at least a driver (D-i) authorised to access the vehicle (1) on which it is installed - said control unit (101) includes means (1010) to generate, on the basis of the data (di) received by said communication module, at least a first access code (C-i) to said vehicle and

- said control unit includes means (1010) to compare said first access code to a second code (C₂) received (S₄) from a customer identification device (200) and to grant or not access to said vehicle as a result of this comparison.

2. System according to claim 1 , characterized in that communication between said server and said module takes place via long distance wireless telecommunication network (300, 300').

3. System according to one of the previous claims, characterized in that communication between said server (400) and said module (107) is encrypted.

4. System according to one of the previous claims characterized in that communication between said control unit (101) and said customer identification device (200) is encrypted.

5. System according to one of the previous claims, characterized in that said customer identification device (200) includes means (2010) to generate said second code (C₂) on the basis of identification (d'-i) data concerning a user (D₁) it is allotted to.

6. A method for sharing vehicles (1 , 1'), in a fleet (F) between several users D₁, D₂), characterized in that it comprises at least the following steps: a) - information data (d-i) relating to at least one user (D₁) having authorised access to a vehicle (1) is sent wirelessly to a communication module (107) connected to an access control unit (101) installed onboard said vehicle b) - said control unit generates (1004) a first access code (C₁) on the basis of the received data c) - when an attempt is made to access and/or start said vehicle, said unit requests (3003) a second code (C₂) from a customer identification device (200) and compares (3007) said second code to said first code and d) - depending on the result of comparison steps c), said control unit grants (3008) or not access to said vehicle.

7. Method according to claim 6, characterized in that it comprises a step of storing in a data base (401 ) identification data relating to all registered users (D₁, D₂), the data (d-i) being sent (1002) in step a) by a server (400) having access to said database.

8. Method according to one of claims 6 or 7, characterized in that steps a) and b) are performed each time a new user (D-i) is authorised to access a vehicle (1), whereas steps c) and d) are performed each time an attempt is made to access and/or start said vehicle.

9. Method according to one of claims 6 to 8 characterized in that in step c), comparison between said first and second codes (C₁, C₂) is made on a part (F₁, F₂) of said codes.

10. Method according to one of claims 6 to 9, characterized in that when several users (D₁, D₂) are authorised to access a vehicle (1), first access codes (C₁) corresponding to each user are generated by said control unit (101) and, during step d), comparison takes place between said second code (C₂) received from a customer identification device (200) and each first code, up to when one detects that the user corresponding to said device (200) is an authorised user or up to when said second code has been unsuccessfully compared to all first codes.

11. Method according to one of claims 6 to 9 characterized in that when several users (D₁, D₂) are authorised to access a vehicle, a signal (S₃) representative of the first code (Ci) for each authorised user is sequentially sent to the customer identification device (200) and comparison takes place between said first and second codes (C-i, C₂), up to when one detects that the user corresponding to said device is an authorised user or up to when representative signals corresponding to all authorised users have been sent unsuccessfully.

12. Method according to one of claims 6 to 11 , characterized in that in step b), said first code (C-i) is computed by a function (f-0 having said identification data (d-i) as a variable.

13. Method according to one of claims 6 to 12, characterized in that the second code (C₂) provided by a customer identification device (200) is generated by said customer identification device on the basis of identification data (d'₁) concerning a user (D-i) to whom this device is allotted.

14. Method according to claim 13, characterized in that said second code (C₂) is computed by a function (f₂) having said identification data (d'i) as a variable.

15. Method according to claims 11 and 14, characterized in that the same function (fi, h) is used to generate said first and second codes (C-t, C₂) on the basis of said identification data (d-i, d'i).