Method for detecting the contact state of a car's starter switch

Abstract

The present invention relates to a method (100) for detecting the contact state of a starter switch of an automobile, the method (100) includes the steps of: receiving a raw signal that reflects information about the contact state of the switch (101); filtering the signal bounce of the raw signal (102); identifying a first contact state of the switch from the filtered raw signal (103); identifying a second contact state of the switch from the received raw signal (105); triggering a time counter if the identified second contact state is different from a previously identified second contact state (106); comparing the identified first and second contact states when the time counter has run out (107); and selecting the identified second contact state as safe information if they are different (108).

Description

Technical Field

[0001] One aspect of the present invention relates to a method for detecting the contact state of a starter switch of a motor vehicle. A particularly advantageous application of the present invention is in the field of motor vehicles equipped with an internal combustion engine and / or an electric motor.

Background Art

[0002] Motor vehicles equipped with an ignition key are known. To start the motor vehicle, the key is inserted into the key cylinder and turned from a position called OFF to a position called ON. To turn the motor vehicle off, the key is turned in the opposite direction and moved from the ON position to the OFF position.

[0003] Motor vehicles equipped with an electronic key card are also known. According to one implementation, when the driver wants to start the motor vehicle, the key is inserted into the housing provided for the card and the start button is pressed. To turn the motor vehicle off, the driver presses the start button again.

[0004] In the case of a non-contact electronic key card, the driver gets in the vehicle with their electronic key card and presses the start button to start the motor vehicle, and presses it again to turn it off.

[0005] When the driver turns the ignition key in the key cylinder of their vehicle, the starter switch of the motor vehicle moves from the open position to the closed position. From the raw signal reflecting the contact state of the starter switch, i.e., the open state called OFF and the closed state called ON of the starter switch, the computer of the motor vehicle executes a filtering step of the raw signal.

[0006] In reality, when a driver turns the ignition key in a car's ignition switch, the electrical contact of the starter switch is not always fully established on the first turn, resulting in a bounce in the raw signal. This type of filtering is known as "anti-bounce" filtering. This filtering step attenuates such bounces in the raw signal.

[0007] From this filtered signal, the computer infers the state of the starter switch contacts, and therefore whether the driver wants to start or turn off the car's engine.

[0008] With this method, if a software error occurs in the filtering of the raw signal, the inferred contact state of the starter switch may be incorrect. Therefore, if the starter switch is closed and this method detects an incorrect contact state of the starter switch, i.e., an open state in this case, this method may prevent the driver from starting their car's engine.

[0009] Conversely, if the starter switch is in an open state, and the system detects an incorrect state of the starter switch, i.e., a closed state, the car's engine may remain running even though the driver wants to turn it off. [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] The object of the present invention is to overcome the shortcomings of the prior art by proposing a method for detecting the contact state of an automobile starter switch, thereby preventing erroneous detection of the contact state of the switch. [Means for solving the problem]

[0011] In this regard, the present invention, therefore in its broadest sense, relates to a method for detecting the contact state of a starter switch of an automobile, wherein the automobile includes a computer comprising a first detection module for a first contact state of the starter switch and a second detection module for a second contact state of the starter switch, and the method comprises the following steps, namely: - A step of receiving a raw signal that reflects information regarding the contact state of the starter switch, wherein the raw signal is received by a first detection module and a second detection module. - The first detection module performs the step of filtering out bounces from the raw signal, - A first detection module identifies a first contact state of the starter switch from the filtered raw signal, - The second detection module identifies the second contact state of the starter switch from the received raw signal, - If the identified second contact state is different from the previously identified second contact state, trigger a time counter, - When the time counter runs out, - A step of comparing the identified first contact state with the identified second contact state, - If the identified first contact state and the identified second contact state are different, the step of selecting the identified second contact state as safe information, Includes.

[0012] According to the method of the present invention, a first contact state identified from the filtered raw signal is compared with a second contact state identified from the filtered raw signal. Since the second contact state is not filtered, there is virtually no software processing involved. Therefore, even if an anomaly occurs during software processing performed by the first module, this anomaly cannot be reproduced by the second module. Thus, by comparing the first contact state obtained by filtering the raw signal with the second contact state obtained from the unfiltered raw signal, it is possible to identify software anomalies that may occur during filtering. In this case, the contact state used by the vehicle's safety function is the second contact state.

[0013] In addition to the features described in the previous paragraph, the method according to this aspect of the present invention may have one or more additional features from the following, which may be individually or in any technically feasible combination.

[0014] According to a non-limiting aspect of the present invention, if a specified first contact state and a specified second contact state are the same, the method includes the step of selecting the specified first contact state as safe information.

[0015] According to an unlimiting aspect of the present invention, the method includes the step of synchronizing at least two cores of a computer to transmit a identified first contact state to the two cores, the synchronization step following the step of identifying the first contact state.

[0016] According to an unspecified aspect of the present invention, the time counted by the time counter is equal to the time required for at least the first detection module to identify the first contact state.

[0017] According to a non-limiting aspect of the present invention, if a specified first contact state and a specified second contact state are different, the method includes the step of recording information reflecting the difference in the vehicle's non-volatile memory.

[0018] According to a non - limiting aspect of the present invention, when a specified first contact state and a specified second contact state are different, the method includes the step of resetting a computer.

[0019] According to a non - limiting aspect of the present invention, when a reset of the computer is performed, the method includes the step of counting the resets, and the step of resetting the computer is prohibited when the number of resets reaches a threshold.

[0020] According to a non - limiting aspect of the present invention, the received raw signal is a logic signal.

[0021] Another aspect of the present invention relates to a motor vehicle including a computer configured to execute the steps of the method according to any one of the above aspects.

[0022] According to an aspect of the present invention, the computer includes a first detection module for a first contact state of a starter switch of the motor vehicle and a second detection module for a second contact state of the starter switch, and the second detection module is a detection module called ASIL.

[0023] The present invention and its various applications will be better understood by reading the following description and referring to the accompanying drawings.

[0024] The drawings are provided as a completely non - limiting representation of the present invention.

Brief Description of the Drawings

[0025] [Figure 1] A motor vehicle according to a non - limiting aspect of the present invention is schematically shown. [Figure 2] The steps of a method according to a non - limiting aspect of the present invention are schematically shown.

Modes for Carrying Out the Invention

[0026] Unless otherwise specified, the same element shown in different drawings shall have the same reference number.

[0027] Figure 1 schematically shows an automobile 1 according to a non-limiting implementation of the present invention.

[0028] In this exemplary embodiment, the automobile 1 is an automobile equipped with an internal combustion engine 2.

[0029] Automobile 1 includes a computer 3, for example, an engine computer formed by a microprocessor.

[0030] Computer 3 includes a first detection module for a first contact state of the starter switch 5 and a second detection module 6 for a second contact state of the starter switch 5.

[0031] The first detection module 4 is configured to process data from the internal combustion engine 2. The second detection module 6 is configured to check, in part, the data processing performed by the first detection module 4. The second detection module 6 is, for example, a module called ASIL C (an abbreviation for "Automotive System Integrity Level C").

[0032] The starter switch 5 can be activated by the ignition key.

[0033] During the transition between the open and closed states of the starter switch 5, a raw signal is generated that reflects information about the contact state of the starter switch 5.

[0034] From this raw signal, the computer 3 is configured to perform the steps of a method 100 for detecting the contact state of the starter switch 5 of the automobile 1 according to the present invention, as shown in Figure 2.

[0035] Method 100 includes step 101 of receiving a raw signal that reflects information regarding the contact state of the starter switch 5. According to a non-limiting embodiment, the raw signal is a logic signal that can take a value of 0V or 5V.

[0036] The same raw signal is received by both the first detection module 4 and the second detection module 6.

[0037] Next, the first detection module 4 performs a filtering step 102 on the received raw signal for bounces of the raw signal. This filtering step prevents false detections.

[0038] The first detection module 4 then performs the next step 103, which identifies the first contact state of the starter switch 5 from the previously filtered raw signal.

[0039] According to a non-limiting embodiment, the first detection module 4 performs the following step 104, which synchronizes at least two cores (not shown) of the computer 3. Thus, the first contact state identified during step 103 is transmitted to the two cores.

[0040] In parallel with steps 102-104, method 100 includes step 105, in which a second detection module 6 determines a second contact state of the starter switch 5 in response to a raw signal received during step 101.

[0041] If the second contact state identified by the second detection module 6 is different from the second contact state previously identified by the second detection module 6, method 100 includes step 106 of triggering a time counter, which is performed by the second detection module 6.

[0042] If the identified second contact state differs from the previously identified second contact state, this is due to a transition of the starter switch 5 from the closed state to the open state, or vice versa.

[0043] The time counted by the time counter is equal to at least the time required for the first detection module 4 to identify the first contact state.

[0044] In this case, the time counted by the time counter is equal to the time required for the first detection module 4 to identify the first contact state and synchronize the two cores.

[0045] The time required for the first detection module 4 to identify the first contact state and synchronize the two cores can be, for example, 20ms to 40ms, typically 30ms. Therefore, the time counted by the time counter can be 30ms.

[0046] When the time counter runs out, method 100 includes step 107, which is performed by computer 3, comparing the first contact state identified in step 103 with a second contact state identified in step 105.

[0047] If the identified first and second contact conditions are different, method 100 includes step 108 of selecting the second contact condition identified by the second detection module 6 as safe information.

[0048] Information reflecting the contact state identified from the raw signal is more reliable than information identified from the filtered signal after software processing. Software processing can, in fact, introduce errors during data processing. Therefore, if there is a difference between the first and second contact states identified by the method according to the present invention, the safety software function of the computer of the automobile 1 uses the second contact state as input data.

[0049] If the identified first contact state and the identified second contact state are different, method 100 may include step 109 of recording information reflecting the difference in the non-volatile memory of the vehicle 1. Thus, during the diagnosis of the vehicle performed by the after-service personnel, the after-service personnel can identify the anomaly and correct it as necessary, for example by updating the software embedded in the first detection module 4.

[0050] Furthermore, according to a non-limiting implementation, if the identified first contact state and the identified second contact state are different, method 100 includes a step 110 of resetting computer 3. By resetting computer 3, the malfunction of the software embedded in the first detection module 4 can be corrected.

[0051] However, if resetting computer 3 several times does not correct this malfunction, continuing to reset it will be pointless.

[0052] Therefore, if the computer 3 is reset, method 100 includes a step 111 for counting the resets, and if the number of resets reaches a threshold, for example 2, step 110 for resetting the computer 3 is prohibited.

[0053] According to a non-restrictive implementation, if the identified first contact state and the identified second contact state are the same, method 100 includes step 112 of selecting the first contact state as safe information. In this case, the second contact state confirms that the identified first contact state is correct.

Claims

1. A method (100) for detecting the contact state of a starter switch (5) of an automobile (1), wherein the automobile (1) includes a computer (3) having a first detection module (4) for a first contact state of the starter switch (5) and a second detection module (6) for a second contact state of the starter switch (5), and the method comprises the following steps, namely, - Step (101) of receiving a raw signal that reflects information regarding the contact state of the starter switch (5), wherein the raw signal is received by the first detection module (4) and the second detection module (6), - The first detection module (4) filters out the bounce of the raw signal (102), - The first detection module (4) identifies the first contact state of the starter switch (5) from the filtered raw signal (103), - The second detection module (6) identifies the second contact state of the starter switch (5) from the received raw signal (105), - If the identified second contact state is different from the previously identified second contact state, the step (106) of triggering a time counter, - When the aforementioned time counter runs out, - A step (107) of comparing the identified first contact state with the identified second contact state, - If the identified first contact state and the identified second contact state are different, the step (108) of selecting the identified second contact state as safe information, A method that includes this.

2. The method according to claim 1 (100), characterized in that if the identified first contact state and the identified second contact state are the same, the first contact state is selected as safe information (112).

3. The method (100) according to claim 1 or 2, comprising a synchronization step (104) of synchronizing at least two cores of the computer (3) to transmit the identified first contact state to the at least two cores, wherein the synchronization step (104) follows the step (103) of identifying the first contact state.

4. The method according to any one of claims 1 to 3 (100), characterized in that the time counted by the time counter is equal to at least the time required for the first detection module (4) to identify the first contact state (103).

5. The method (100) according to any one of claims 1 to 4, characterized in that if the first identified contact state and the second identified contact state are different, the method (100) includes the step (109) of recording information reflecting the difference in the non-volatile memory of the automobile (1).

6. The method (100) according to any one of claims 1 to 5, characterized in that if the first identified contact state and the second identified contact state are different, the method (100) includes the step (110) of resetting the computer (3).

7. The method (100) according to any one of claims 1 to 6, wherein if the computer (3) is reset, the method (100) includes a step (111) of counting the reset, and the step (110) of resetting the computer (3) is prohibited when the number of resets reaches a threshold.

8. The method according to any one of claims 1 to 7 (100), characterized in that the received raw signal is a logic signal.

9. An automobile (1) comprising a computer (3) configured to perform the steps of the method (100) according to any one of claims 1 to 8.

10. The automobile (1) according to claim 9, wherein the computer (3) includes a first detection module (4) for a first contact state of the starter switch (5) of the automobile (1) and a second detection module (6) for a second contact state of the starter switch (5), the second detection module (6) being a detection module called ASIL.

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