EP1747538A1

EP1747538A1 - Method for preventing the erroneous triggering of a passive access system of a motor vehicle

Info

Publication number: EP1747538A1
Application number: EP05742695A
Authority: EP
Inventors: Aytac Daghan; Franz Plattner
Original assignee: Siemens AG
Current assignee: Continental Automotive GmbH
Priority date: 2004-05-17
Filing date: 2005-04-21
Publication date: 2007-01-31
Anticipated expiration: 2025-04-21
Also published as: JP2008500476A; WO2005114592A1; US20080012694A1; EP1747538B1; EP1747538B8; DE102004024387B3

Abstract

The invention relates to a method for preventing the erroneous triggering of a passive access system of a motor vehicle, said access system comprising at least one handle (2) on the vehicle and at least one capacitive sensor (3), which is situated in the vicinity of the handle (2), is connected to a central control unit (4) and triggers a data identification interrogation of a data carrier in the user's possession by the central control unit (4), if the handle (2) is actuated. The method comprises the following steps: determination of the number (i) of cases of negative data identification that have already been carried out during a pre-determined time period by means of the central control unit (4); comparison of the determined number (i) of negative identification cases with a pre-determined threshold value (j) by means of the central control unit (4); and additional data identification interrogation by the central control unit (4), if the number (i) of negative data identification cases that has been determined is less than the pre-determined threshold value (j), or transmission of a new referencing command signal by the central control unit (4) to the capacitive sensor or sensors (3) in order to obtain a new reference for the latter, if the number (i) of negative data identification cases that has been determined is equal to the pre-determined threshold value (j).

Description

description

Method for preventing false triggering of a passive access system in the motor vehicle sector

The present invention relates to a method for preventing false triggering of a passive access system in the motor vehicle area, in particular a passive access system which has a vehicle-side handle and a capacitive sensor arranged in the area of the handle, which is connected to a central control unit and a data identification query of an operator triggered data carrier by the central control unit in the event of actuation of the handle.

Although applicable to any functions integrated in the vehicle, the present invention and the problems on which it is based are explained in more detail with regard to a locking mechanism or a passive locking system of a vehicle door.

In locking systems of the type mentioned above, it is known to give access to a person, for. B. a vehicle via a data query of a data carrier, for. B. a key card. The data query is here by a mechanical switch attached to the vehicle or a sensor, for. B. a light barrier, which are installed on a door handle or at least in the area of a door handle. The person requesting access triggers the data query of the data carrier by a control unit in a vehicle by actuating a handle, more precisely by moving the door handle or by passing a light barrier with one hand. The triggered pulse is passed on from the control unit to a transmitter, which sends the data request to the data carrier. ger transmitted. The data carrier receives the data query command and forwards it to a data unit, which forwards the required data to a transmitter. The transmitter then transmits the data again via the vehicle-side transmission / reception unit to the control unit in the vehicle, which in the event of positive data recognition issues a command to unlock the locking system.

The document DE 196 17 038 C2 describes a locking system in which at least one electrode is installed in the handles of the door handles of the vehicle and in the part of the motor vehicle door opposite the handle, a counter electrode is attached, which can also be the door itself. If an electrical field is built up between the two electrodes, this can advantageously be used to already sense the access request of a person reaching for a door handle. According to DE 196 17 038 C2, this is done in that a hand which reaches for a handle located on the door already changes the capacitance built up between the two electrodes when it approaches. The hand has the special function of changing the dielectric between the handle-side electrode and the counter electrode on the door side by replacing part of the ambient air with the dielectric of the hand and thus summatively resulting in a different overall dielectric. Electronics, which perceive the change in capacity and translate it into a command pulse, are included in the handle of the door handle, for example. The command pulse generated by this electronics triggers the query of the operator-side data carrier in a central control unit, as already explained above.

This approach according to the prior art, however, has shown the disadvantage that at perma Changes in the ambient air or the overall dielectric caused, for example, by rain, snow or slush in the area of the capacitive sensors. False triggers of the locking system mentioned above occur. After triggering, the sensor must remain static for a predetermined time in order to be able to recognize whether the triggering conditions, for example the finger applied to the handle, are still present. As a result of the temporary static property of the capacitive sensor, in the event of false triggers caused by, for example, rain, snow or slush, cyclical activity of the connected control devices of such a passive access system occurs, since the control units start search sequences in order to search for any data carriers present on the user side, for example a data carrier Key card to authenticate. In order to be able to recognize an actuation of the handle or an end of the actuation process, the sensor must not be able to adapt to such an actuation. Due to the cyclical activity of the control unit or units, this leads to increased power consumption, which means that the battery can be discharged overnight, particularly in rain or snow. This means that the motor vehicle user cannot open his vehicle electronically in the morning and cannot start it straight away.

DE 197 45 149 C2 discloses a passive access system in the motor vehicle sector, with a capacitive sensor which is connected to a central control unit and triggers a data identification query of an operator-specific data carrier when the handle is actuated.

It is known from DE 195 32 744 C2, DE 146 12 026 C2 and EP 785 114 A2 to determine the number of days performed.

to identify all of them and compare them with a predetermined threshold value.

Finally, DE 196 10 275 C2 discloses using the central control unit to record the number of negative data identification cases that have already been carried out and to compare them with a predetermined threshold value.

In the prior art, there is the approach that the capacitive sensor or sensors are automatically switched off depending on a predetermined period of time and depending on an actuation process. The locking system is therefore no longer functional, so that the motor vehicle user will find a locked locking system. This leads to considerable customer dissatisfaction.

The present invention is therefore based on the object of providing a method for preventing false triggering of a passive access system, in particular in the event of rain, snow or slush, without having to completely switch off the locking system or the access system.

According to the invention, this object is achieved by the method having the features of patent claim 1.

The idea on which the present invention is based is that the method according to the invention has the following procedural steps: detection of the number of negative data identification cases already carried out in a predetermined period of time by means of the central control unit; Comparing the recorded number of negative data identification cases with a predetermined threshold value by means of the central control unit; and performing a further data identification query by the central control unit in the event that the detected number of the new gative data identification is less than the predetermined threshold or sending a re-reference command signal from the central control unit to the capacitive sensor for re-reference thereof in the event that the detected number of negative data identification cases is equal to the predetermined threshold.

The present invention thus has the advantage over the known approaches according to the prior art that the capacitive sensor, due to the self-carried out re-referencing, comes into its retirement in the event of a predetermined number of negative data queries already carried out, in which only a low power consumption takes place. The system therefore remains fully functional even in the event of rain or snow after a long period of non-operation, since false triggers only lead to increased power consumption for a predetermined period of time if there is no identification transmitter associated with the vehicle in the vicinity of the vehicle.

Advantageous refinements and developments in the invention are the subject of the further subclaims and the description with reference to the figures of the drawing.

According to a preferred development, the predetermined threshold value is stored in advance in a storage device. The storage device is preferably connected to the central control unit. The predetermined threshold value can be 2 or 3, for example. It is obvious to a person skilled in the art that other threshold values are also possible, depending on which power consumption is tolerated in the successive queries.

According to a further preferred development, the capacitive sensor is re-referenced in the static one Commanded operation of the handle by the central control unit. This ensures that when the central control unit receives a new reference command signal, the capacitive sensor re-calibrates itself or readjusts its zero position in such a way that it adapts to the static state.

After each change in a door contact state, for example when the vehicle door is closed, a re-reference command signal is sent from the central control unit to the capacitive sensor for re-reference of the same. This prevents false triggering, for example, by closing the vehicle - occur door.

According to a further preferred exemplary embodiment, the exterior mirrors are folded in, the door locking device is activated, side windows are closed and / or further vehicle state changes are carried out, for example, when the handle for closing a vehicle door is actuated by means of a positive data identification case. In an analogous manner, in the event of a positive data identification, when the handle is actuated to open the vehicle door, for example the exterior mirrors are unfolded, the door locking device deactivated, side windows opened and / or further vehicle state changes are carried out.

A plurality of capacitive sensors are preferably provided in the vehicle, one sensor being arranged on each door, flap or the like, for example.

After actuation of the handle and the associated triggering of a data identification query, as a check carried out by the central control unit whether there are any unused user-side data carriers in the vehicle, for example data carrier cards in the glove compartment of the vehicle, in which case these data carriers are hidden and are not taken into account for the further process. False triggers due to data carriers that are inadvertently located in the vehicle are thus avoided.

The invention is explained in more detail below with reference to the exemplary embodiments given in the schematic figures of the drawing. It shows:

FIG. 1 shows a schematic view of a vehicle with an integrated passive access system according to an exemplary embodiment of the present invention;

FIG. 2 shows a side cross-sectional view of a handle and part of a vehicle door according to an exemplary embodiment of the present invention; and

Figure 3 is a schematic block diagram of a process flow according to the invention according to a preferred embodiment of the present invention.

In the figures of the drawing, the same or functionally identical components have been provided with the same reference numerals, unless stated otherwise.

Figure 1 illustrates a schematic view of a vehicle with an integrated passive access system, which is designed only as an example as a locking system for locking or unlocking a vehicle door. As can be seen in FIG. 1, each door preferably faces 1 each have a door handle that includes a handle 2. The handle 2 can be designed, for example, as a handle bar or the handle flap, which contains a capacitive sensor 3. Conductors run from the respective capacitive sensors 3 to a central control unit 4 from the handles 2 or the door handles. A signal from the capacitive sensor 3 is triggered via these conductors when a hand approaches the space between the handle 2 and door 1 the central control unit 4 delivered. In the central control unit 4, such a signal triggers a data request from an operator-side data carrier (not shown), the central control unit 4 passing on the signals to a plurality of transmitting / receiving units 8, which transmit the data request electromagnetically to the data carrier.

The data output command, for example, is received in the data carrier via an antenna and forwarded to a recipient of the data carrier. The receiver forwards the signal to a data unit of the data carrier, which transmits the data to be called up via a transmitter and the antenna of the data carrier to the transmitting / receiving units 8 in the vehicle.

The transmitting / receiving units 8 pass on the received data to the central control unit 4 via conductor tracks. In the central control unit 4, the data supplied by the data carrier are compared with the identification data stored in a storage device 5 connected to the central control unit 4. In the event of positive data identification (recognition of access authorization), the central control unit 4 uses suitable connections to pass on a signal for unlocking the locking device 7, which switches the handle 2 from an inactive to an effective mode. In this effective stood the handle 2 is an opening of the locking devices 7 by operating the handle 2 possible.

The power supply to the locking system, the central control unit 4 and the other effective electrical components is preferably taken over by the car battery 9 present in the vehicle.

FIG. 2 illustrates a side cross-sectional view of a handle 2 and a part of the motor vehicle door 1. As can be seen in FIG. 2, the handle 2 of the door handle has a first electrode 10 and the region of the door handle on the vehicle has a second electrode 11, between which the electrical field is located 12 spreads.

With reference to FIG. 3, a method for preventing false triggering of such an access system or locking system according to a preferred exemplary embodiment of the present invention is explained in more detail below.

In the event of a change in the electrical field 12 in FIG. 2 between the two electrodes 10 and 11 of the door handle, for example due to the engagement of fingers, electronics, as already mentioned above, perceive the change in capacitance and convert this change into a command pulse, which is sent to the central control unit 4 via suitable lines. The command pulse generated by this electronics triggers a data identification query on a user-side data carrier in the central control unit 4.

In a further method step, the central control unit 4 checks the extent to which, for example, after the motor vehicle door has been closed, further used user-side data carriers are located inside the motor vehicle, for example in the glove compartment. If data carriers on the operator side are located within the vehicle, they are hidden by the central control unit 4, so that they are not taken into account further for further method steps. Unwanted identification data of such data carriers can thus advantageously be hidden.

The central control unit 4 then preferably checks how often unsuccessful queries or negative data identification cases have already been carried out within a predetermined, previous period. A negative data identification case occurs when a query by the central control unit 4 shows that there is no identification transmitter or data carrier on the vehicle, the data carriers undesirably located in the vehicle possibly not being taken into account, as has already been explained above.

The central control unit 4 is preferably connected to a memory device 5, in which, in particular, the predetermined time period for checking the number i of the negative data identification cases already carried out and a predetermined threshold value j are stored. The threshold value j is preferably 2 or 3 and denotes the maximum number of identification queries to be carried out by the central control unit 4 before the capacitive sensor 3 is re-referenced, which will be described in more detail below.

According to a subsequent method step, the central control unit 4 compares the detected number i of the negative data identification cases already carried out in the predetermined period with that in the memory device 5 previously stored threshold value j. A threshold value j equal to 2 is assumed for the following explanations. However, different threshold values are of course also possible.

If a comparison by the central control unit 4 reveals that the number i of negative identification cases already carried out is less than the stored threshold value j equal to 2, the central control unit 4 carries out a further data identification query.

However, if the comparison reveals that the number i of the negative identification cases already carried out corresponds to the stored threshold value j equal to 2, the central control unit 4 sends a re-re-enablement command.

Signal to the respective capacitive sensor 3 in order to initiate targeted re-referencing of this adaptive capacitive sensor 3.

Thus, in the static phase of an actuation, the capacitive sensor 3 is requested by the received re-referencing command signal to automatically recalibrate itself or to re-calibrate its zero position, so that, for example, moisture or snow, which may cover the sensor area, do not trigger certain changes in state incorrectly , such as unlocking or locking the motor vehicle door 1, folding in or folding out side mirrors, raising or lowering windows, or the like. Due to the new generation of the capacitive sensor 3, the triggering condition due to, for example, the moisture or snow located in the sensor area is no longer fulfilled, and the sensor 3 no longer detects actuation. This means there is no energy-consuming data identification. Decoration query, which significantly reduces the total energy consumption.

As can also be seen in FIG. 3, certain functions of the vehicle are actuated by the central control unit 4 in the case of a positive data identification query. As already explained above, this can be a locking or unlocking of the door, an opening or folding of the doors. mirrors, opening or closing windows, and / or other vehicle condition changes.

As is additionally shown in FIG. 3, the capacitive sensor 3 can also be re-referenced whenever the door contact state changes, so that, for example, each time the door 1 is closed, the associated capacitive sensor (s) 3 are referenced in such a way that no false triggering by the Closing door 1 takes place.

The present invention thus provides a method with which false triggers of a passive access system can be prevented in a simple and inexpensive manner. By means of the method according to the invention, the access system remains constantly ready for operation even in the event of disturbances in the electrical field, for example due to rain or snow or other disturbance variables. According to the method according to the invention, false triggers caused by such disturbance variables require an increased quiescent current only over a short period of time, namely during the passage of the data identification queries with a number according to the predetermined threshold value, if there is no identification transmitter or data carrier associated with the vehicle on the vehicle. After having run through predetermined query cycles, the access system is retired, in which only a low power consumption takes place. Consequently emptying of the vehicle battery can be advantageously prevented without having to forego the permanent functionality of the access system.

Although the present invention has been described above on the basis of preferred exemplary embodiments, it is not restricted thereto, but rather can be modified in many ways.

Claims

claims

1. A method for preventing false triggering of a passive access system in the motor vehicle area, the access system having at least one handle (2) on the vehicle side and at least one capacitive sensor (3) arranged in the area of the handle (2) which is connected to a central control unit ( 4) is connected and triggers a data identification query of a data carrier on the operator side by the central control unit (4) when the handle (2) is actuated, the method comprising the following method steps: detecting the number (i) already in a predetermined period of time performed negative data identification cases

15 by means of the central control unit (4); Comparing the detected number (i) of the negative data identification cases with a predetermined threshold value (j) by means of the central control unit (4); and performing another data identification query

20 by the central control unit (4) in the event that the detected number (i) of the negative data identification cases is less than the predetermined threshold value (j), or sending a re-reference command signal from the central control unit (4) to the at least one capacitive

25 Sensor (3) for re-referencing the same in the event that the detected number (i) of the negative data identification trap is equal to the predetermined threshold value (j).

2. The method according to claim 1, characterized in that the predetermined threshold value (j) is previously stored in a storage device (5) connected to the central control unit (4). 35

3rd Method according to Claim 1 or 2, ie that the predetermined threshold value (j) is 2 or 3.

4. The method according to at least one of the preceding claims, characterized in that a re-referencing of the at least one capacitive sensor (3) in the static phase of an actuation of the handle (2) is commanded by the central control unit (4).

5. The method according to at least one of the preceding claims, characterized in that the at least one capacitive sensor (3) itself recalibrates its zero position when the central control unit (4) receives a re-reference command signal.

6. The method according to at least one of the preceding claims, characterized in that after each change in a door contact state, a new reference command signal is sent from the central control unit (4) to the at least one capacitive sensor (3) for a new reference.

7. The method according to at least one of the preceding claims, characterized in that in the case of a positive data identification case when the handle (2) is actuated to close a vehicle door (1) the exterior mirrors folded in, the door locking device (7) activated, side windows closed, and / or further changes in the state of the vehicle are carried out.

8. The method according to at least one of the preceding claims, characterized in that in the event of a positive data identification when the handle (2) is actuated to open a vehicle door (1), the exterior mirrors are unfolded, the door locking device (7) is deactivated, side windows are opened and / or further state changes of the vehicle are carried out.

9. The method according to at least one of the preceding claims, characterized in that a plurality of capacitive sensors (3) in the vehicle, preferably one sensor (3) on each door (1), each flap or the like, are provided.

10. The method according to at least one of the preceding claims, characterized in that after actuation of the handle (2) and the associated triggering of a data identification query, a check is carried out by the central control unit (4) whether there are any unused user-side data carriers in the Vehicle. In such a case, these data carriers are hidden and are not taken into account for the further procedure.