VEHICLE NETWORK AND METHOD FOR ESTABLISHING A VEHICLE NETWORK

Abstract

A vehicle network for a plurality of interconnected vehicles is disclosed. The network is in the form of a WLAN and has at least two access points. The access points are interconnected in a wireless manner, i.e., without using a wired backbone. Each access point uses the same radio network ID, so all access points form only one single visible network for WLAN clients. A method for establishing the vehicle network is also disclosed.

Claims

1. A vehicle network for a plurality of interconnected vehicles, wherein the network is implemented as a WLAN and has at least two access points, wherein the access points being interconnected wirelessly, and wherein the access points in each case use the same radio network identifier and form only one single visible network for WLAN clients.

2. The vehicle network as claimed in claim 1, wherein at least one WLAN client forms part of the network.

3. The vehicle network as claimed in claim 1, wherein adjacent vehicles of the network are also physically interconnected and can exchange signals via physical lines.

4. The vehicle network as claimed in claim 1, wherein an electronic control unit is allocated to each access point and data available in the electronic control units are readable via at least one of the access points.

5. A method for establishing a vehicle network comprising at least two access points and one WLAN client, said method comprising the following steps: a) acquiring by a WLAN client connection data of a first vehicle and of a second vehicle, b) connecting the WLAN client connects to an access point of the second vehicle, c) transmitting by the WLAN client connection data of an access point of the first vehicle to the access point of the second vehicle so that the access point of the second vehicle can accept a radio network identifier of the access point of the first vehicle and establish a connection via WDS to the access point of the first vehicle, d) accepting by the access point of the second vehicle the radio network identifier of the access point of the first vehicle to connect to the access point of the first vehicle via WDS, thus forming one single network visible to the WLAN client with the access point of the first vehicle.

6. The method as claimed in claim 5 wherein the network includes a further vehicle, and wherein said method further comprises the following steps: a) connecting the WLAN client to an access point of the further vehicle, b) transmitting by the WLAN client connection data to the access point of the further vehicle so that this access point can accept the radio network identifier of the access points of the network and establish a connection to at least one of the access points of the network via WDS, c) accepting by the access point of the further vehicle the radio network identifier of the access points of the network, to connect to at least one of the access points via WDS, thus becoming part of the network visible to the WLAN client.

7. The method as claimed in claim 5, wherein the vehicles are also physically interconnected, said method further comprising the step of carrying out a check following the establishment of a WLAN connection between the access points of two vehicles to determine whether signals are also transmittable between the two vehicles via physical lines, wherein the WLAN connection between the access points is retained only if the check on the transmission of signals via the physical lines is successful.

8. The method as claimed in claim 5, wherein the WLAN client loads the connection data of a vehicle at least indirectly in a wireless manner.

9. The method as claimed in claim 5, wherein the WLAN client loads the connection data of a vehicle from a server and the server is accessed using the data previously acquired wirelessly by the WLAN client.

10. A control unit for a vehicle with an electronic braking system with an access point allocated to the control unit, wherein the access point is capable of changing its radio network identifier and communicating via WDS with other access points.

11. A control unit to carry out the method as claimed in claim 1.

12. The vehicle network as claimed in claim 2, wherein login information of the WLAN client is forwarded unchanged from access point to access point.

13. The vehicle network as claimed in claim 4 wherein data available in the control units are readable via each of the access points.

14. The method as claimed in claim 8 the WLAN client loads the connection data of a vehicle via a radio link or optically with a camera.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The invention is described in greater detail below with reference to the accompanying figure, in which:

[0034] FIG. 1 shows a combined vehicle with a wireless vehicle network,

[0035] FIGS. 2 to 5 show the sequence for establishing a part of the vehicle network according to FIG. 1,

[0036] FIG. 6 shows a network with a line topology, and

[0037] FIG. 7 shows a network with a meshed topology.

DETAILED DESCRIPTION

[0038] FIG. 1 shows schematically a combined vehicle consisting of a first vehicle/a tractor unit 10, a second vehicle/a first trailer 11 and a third vehicle/a second trailer 12. The first trailer 11 is attached to the tractor unit 10 and the second trailer 12 is attached to the first trailer 11.

[0039] The vehicles have an electronic braking system with a pneumatic braking system. A control unit 13, 14, 15 for the electronic braking system is provided accordingly in each vehicle.

[0040] In addition to the usual trailer couplings, semitrailers 16 and tow bars 17, physical connections 18, 19 exist between the vehicles. In each case, this involves electrical and pneumatic lines, for example for transmitting pneumatic control pressure, brake light signals and braking commands from the tractor unit 10 to the two trailers 11, 12 and/or a CAN interface according to ISO 111992. The control units 13, 14, 15 can transmit signals to one another directly or indirectly via the connections 18, 19.

[0041] In each of the vehicles 10, 11, 12, the relevant control unit 13, 14, 15 is connected to a vehicle-side CAN bus 20, 21, 22, to which further devices are normally connected. In the tractor unit 10, at least an engine control unit 23 and a WLAN unit 24 are also connected to the CAN bus 20. The data available on the CAN bus 20 can be made available via the WLAN unit 24 to a radio network. The WLAN unit 24 may also be integrated into the control unit 13.

[0042] In the two trailers 11, 12, WLAN units 25, 26 are similarly connected to the CAN buses 21, 22. Here also, the WLAN units can be integrated into the respective control unit 14, 15. The data present on the CAN buses 21, 22 can be made available via the WLAN units 25, 26 in a radio network.

[0043] In principle, each of the WLAN units 24, 25, 26 is active as an access point with its own radio network identifier. In the present case, the WLAN units 25, 26 of the trailers 11, 12 are reconfigured and use the radio network identifier of the WLAN unit 24 of the tractor unit 10. The WLAN units 24, 25, 26 are simultaneously interconnected in a wireless manner, i.e. via WDS (Wireless Distribution System). Messages can thereby be transmitted wirelessly from the WLAN unit 24 via the WLAN unit 25 to the distantly located WLAN unit 26, even if the two WLAN units 24 and 26 are located too far away from one another for an interference-free WLAN transmission. This is the case particularly if further trailers are attached to form a road train and a vehicle network is intended to be established over all vehicles.

[0044] A WLAN client 27 can furthermore connect to any of the WLAN units 24, 25, 26 (configured as an access point) and can then move along the vehicles. The WLAN client 27 otherwise always remains connected to the vehicle network. No changeover to different radio network identifiers of access points is required, since, in this case, the WLAN units 24, 25, 26 each use the same radio network identifier as an access point. The movement of the WLAN client 27 from the first trailer 11 to the second trailer 12 is shown in FIG. 1 via the WLAN client 27 drawn at the bottom left with continuous lines and the WLAN client 27′ drawn at the bottom right with dotted lines.

[0045] The WLAN client 27 is, for example, a Smartphone of a driver. The Smartphone has software for making contact with the WLAN units 24, 25, 26 or with the control units 13, 14, 15, for example in the form of an app supplied by the manufacturer of the control units via the Internet.

[0046] The data of the respective vehicle are available at each access point/each WLAN unit 24, 25, 26, at least via the vehicle's own CAN bus 20, 21, 22. The WLAN units operate in each case with the same radio network identifier. However, they have different network addresses (IP addresses), so that the data can be distinguished from vehicle to vehicle. The data can be read from the different vehicles and can be processed with corresponding software on the WLAN client 27. Functions can also be controlled.

[0047] The vehicle network shown essentially has a line-shaped topology without the WLAN client 27, see FIG. 6 with nodes 1, 2, 3 as access points in three interconnected vehicles, e.g. in a motor vehicle with two trailer vehicles. However, the number of vehicles may also be less than the number of nodes/access points. A plurality of access points can thus be present in one vehicle.

[0048] Depending on the range of the radio networks formed from the individual WLAN units, overlaps and therefore a meshed topology may be present, see FIG. 7 with 1 to n nodes/access points, through to a fully meshed system. In the latter, every access point communicates directly and without an intermediate station with every other access point of the same network.

[0049] The structure of the vehicle network is explained below with reference to FIGS. 2 to 5:

[0050] The tractor unit 10 and the first trailer 11 are interconnected as shown in FIG. 1. A driver or other user enters the tractor unit 10 and switches the ignition on there. The electrical systems in the tractor unit 10 and in a physically connected first trailer 11 are thus active.

[0051] The WLAN client 27 is a Smartphone with a camera and image-processing software. The WLAN connection data are disposed in each case as a QR code on an outer surface on the tractor unit 10 and on the first trailer 11. The user records the two QR codes (FIG. 2) with the camera of his Smartphone. The WLAN connection data of the tractor unit 10 and the first trailer 11 are thus stored in the Smartphone.

[0052] The user establishes a radio connection from the Smartphone to the first trailer 11, i.e. to the WLAN unit 25, and notifies the WLAN unit 25 (FIG. 3) that the latter is to accept the radio network identifier of the tractor unit 10 or the WLAN unit 24. The WLAN of the trailer 11 is then switched off and restarted, now with the same radio network identifier as the tractor unit 10. A temporary vehicle network now exists via the tractor unit 10 and the first trailer 11.

[0053] The user requests an authorization via his Smartphone, for example the actuation of the foot brake and/or the release of the hand brake. The user/driver or a third person enters the tractor unit 10 and performs the required action. A modified control pressure and/or a brake light signal are thereby transmitted from the tractor unit 10 to the first trailer 11 (see FIG. 4, bold-printed physical connection 18 with a dotted further connection). The signals are detectable by the control unit 14. The control unit 14 sends the requested confirmation via the WLAN unit 25 to the Smartphone. It is thus ensured that the tractor unit 10 and the first trailer 11 physically coupled to it form parts of the vehicle network. The temporary vehicle network becomes a permanent vehicle network which remains in place until a termination instruction follows and/or the first trailer 11 is disconnected from the tractor unit 10.

[0054] If the confirmation of the physical connection of the tractor unit 10 and the first trailer 11 explained with reference to FIG. 4 fails, the common vehicle network is rejected. A re-establishment is possible. The physical connection between the tractor unit 10 and the trailer 11 should first be checked.

[0055] The authorization request to check the physical connection can also be made in an automated manner. Either the driver must be manually active (as described here) or the process of signal generation and subsequent signal checking on the physical connection is similarly performed in an automated manner, for example via software in the access point, the radio network identifier of which is intended to be accepted by other access points.

[0056] In the permanent vehicle network according to FIG. 5, the WLAN client 27 (Smartphone) can access the data present in the control units 13, 14 and the CAN buses 20, 21 via each of the two WLAN units 24, 25. It is no longer necessary for the WLAN client 27 to be connected precisely to the WLAN unit of the vehicle concerned. Instead, the data are forwarded if necessary from access point to access point through to the WLAN client.

[0057] A further trailer (the second trailer 12 in FIG. 1) can be added in the same way. The connection data of the tractor unit 10 are stored in the Smartphone. The Smartphone records the connection data of the further trailer and makes contact as a WLAN client 27 with the WLAN unit 26 and notifies the latter that it is to use the radio network identifier and the encryption of the WLAN unit 24. WLAN unit 26 is then switched off and restarted, now with the radio network identifier of the WLAN unit 24 of the tractor unit 10. The second trailer 12 has previously been connected to the first trailer 11. An authorization via the physical connection is thus also possible in the manner described.

[0058] Further trailers can thus be added gradually. A uniform vehicle network is created even if the distantly located trailers themselves have no direct radio connection to the tractor unit 10. In the network consisting of the tractor unit and a plurality of trailers, the respective access points have access to the data of their vehicle known to them and simultaneously to the data of the other access points also. All necessary vehicle data are thus available in a vehicle network for the first time in every vehicle part. New comfort functions and safety functions can be implemented.

[0059] The individual access points communicate with one another via WDS (Wireless Distribution System) in the sense of a point-to-multipoint system. Access points that are located between other access points have the function of a repeater in the network. Access points from one and the same manufacturer are typically used.

[0060] The data available on the respective CAN bus, present in the control units and supplied by connected sensors are available in the vehicle network as a data layer. The aim is to achieve a data transfer and data processing that is as vendor-independent as possible.

[0061] Communication takes place in an exclusively wireless manner in the vehicle network described. A backbone via cable is not provided. The described physical connections 18, 19 are used only for authorization in establishing the vehicle network.