Method and system for diagnosing reliability of an accelerator pedal signal based on temperature and vehicle speed

Abstract

The application discloses a temperature and vehicle speed based accelerator pedal signal reliability diagnosis method and system, and belongs to the technical field of automobiles. The related output signals of an accelerator pedal are collected. Whether the related output signals of the accelerator pedal are normal is judged. Whether the related output signals of the accelerator pedal are unreliable is judged. If it is judged that the related output signals of the accelerator pedal are abnormal or unreliable, a controller triggers corresponding torque limitation, vehicle speed limitation, function limitation, limp home and other related safety processing mechanisms. The controller responsible for the analysis of the accelerator pedal signal collects, analyzes and judges the reliability of the accelerator pedal signal by collecting signals such as the temperature of the accelerator pedal resistor, the feedback signal and the real-time vehicle speed of the CAN bus. Through this method, the reliability of the accelerator signal can be more accurately judged, and the driving safety of the whole vehicle is guaranteed.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology, specifically relating to a method and system for diagnosing the reliability of accelerator pedal signals based on temperature and vehicle speed. Background Technology

[0002] Currently, accelerator pedals used in the domestic automotive market are divided into several types, including mechanical and Hall effect types. Among them, mechanical accelerator pedals occupy a certain market share due to their simple structure and advantages in material and manufacturing costs. These mechanical accelerator pedals transmit the driver's driving intentions through the voltage division of a sliding rheostat within their structure. However, because different types of resistors have different temperature characteristics, and current controllers responsible for accelerator pedal signal analysis do not consider this temperature factor when diagnosing the reliability of the accelerator pedal signal, they cannot accurately identify the reliability of the signal. Summary of the Invention

[0003] To address the problem in existing technologies where temperature is not considered during diagnosis, leading to inaccurate signal reliability assessment, this invention provides a method and system for diagnosing accelerator pedal signal reliability based on temperature and vehicle speed. The controller responsible for accelerator pedal signal analysis collects and analyzes signals such as the temperature of the accelerator pedal resistor, feedback signals, and real-time vehicle speed from the CAN bus to determine the reliability of the accelerator pedal signal. This method enables more accurate determination of acceleration signal reliability, thus ensuring overall vehicle safety.

[0004] This invention is achieved through the following technical solution:

[0005] The accelerator pedal signal reliability diagnosis method based on temperature and vehicle speed includes the following steps:

[0006] S1. Acquire relevant output signals from the accelerator pedal;

[0007] S2. Determine whether the relevant output signals of the accelerator pedal are normal;

[0008] S3. Determine whether the relevant output signal of the accelerator pedal is unreliable;

[0009] S4. If it is determined that the relevant output signal of the accelerator pedal is abnormal or unreliable, the controller should trigger the corresponding safety processing mechanism.

[0010] Furthermore, the output signals of the accelerator pedal include: the voltage of the 5V power supply of the first accelerator pedal sensor, the voltage of the 5V power supply of the second accelerator pedal sensor, the first accelerator pedal signal S1, the second accelerator pedal signal S2, the accelerator pedal resistance temperature, and the real-time vehicle speed.

[0011] Furthermore, the accelerator pedal resistance temperature is measured and collected by a temperature sensor installed on the pedal structure; the real-time vehicle speed is the vehicle speed calculated by the ABS based on the wheel speed collected.

[0012] Furthermore, step S2 specifically includes the following:

[0013] If the voltage of the 5V power supply of the first accelerator pedal sensor or the 5V power supply of the second accelerator pedal sensor is less than the minimum supply voltage, or if the voltage of the 5V power supply of the first accelerator pedal sensor or the 5V power supply of the second accelerator pedal sensor is greater than the maximum supply voltage, then an abnormal supply voltage fault is determined to exist.

[0014] If the first accelerator pedal signal or the second accelerator pedal signal is less than the minimum signal voltage, or if the first accelerator pedal signal or the second accelerator pedal signal is greater than the maximum signal voltage, then an abnormal signal voltage fault is determined to exist.

[0015] Furthermore, step S3 specifically includes the following:

[0016] a: If the accelerator pedal resistance temperature is lower than the minimum rated temperature or higher than the maximum rated temperature, then an unreliable signal fault is confirmed.

[0017] b: When the real-time vehicle speed is 0 < V < V1, if |S1-kS2| > the first maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault.

[0018] c: When the real-time vehicle speed is V1 < V < V2, if |S1-kS2| > the second maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault.

[0019] d: When the real-time vehicle speed is V > V2, if |S1-kS2| > the third maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault.

[0020] Where V is the real-time vehicle speed, and V1 and V2 are calibration values ​​obtained through calibration.

[0021] Furthermore, the temperature coefficient y has the following relationship with the accelerator pedal resistance temperature T, as shown in Table 1;

[0022] Table 1 shows the relationship between the temperature coefficient y and the accelerator pedal resistance temperature T.

[0023] Accelerator pedal resistance temperature T (°C) -40 -30 -20 -10 0 10 20 30 40 50 Temperature coefficient y y1 y2 y3 y4 y5 y6 y7 y8 y9 y10

[0024] On the other hand, the present invention also provides a reliability diagnostic system for accelerator pedal signals based on temperature and vehicle speed, including a vehicle controller, an accelerator pedal, an accelerator pedal resistance and temperature sensor, and an EPS controller; the vehicle controller (VCU) is connected to the accelerator pedal and the accelerator pedal resistance and temperature sensor via hard wiring, and collects two power input signals, two accelerator pedal signals, and accelerator pedal resistance and temperature from the accelerator pedal sensor, and collects the vehicle speed signal sent by the EPS controller via the CAN bus, analyzes the accelerator pedal signal in the current state, and determines the rationality of the signal.

[0025] Compared with the prior art, the advantages of the present invention are as follows:

[0026] The present invention relates to a method and system for diagnosing the reliability of accelerator pedal signals based on temperature and vehicle speed. The method divides the reliability diagnosis of accelerator pedal signals into three vehicle speed levels. By dividing the vehicle speed into segments and setting three different diagnoses at medium, high and low vehicle speeds, the reliability of accelerator pedal signals can be reasonably diagnosed at different vehicle speed levels.

[0027] The diagnostic threshold for accelerator pedal reliability diagnosis is increased by adding a correction value for accelerator pedal resistance temperature, thereby eliminating diagnostic errors caused by different resistance values ​​at different temperatures.

[0028] The controller responsible for accelerator pedal signal analysis determines the reliability of the accelerator pedal signal by collecting and analyzing signals such as the temperature of the accelerator pedal resistor, feedback signals, and real-time vehicle speed from the CAN bus.

[0029] In summary, the diagnostic method of this invention can more accurately determine whether the acceleration signal is reliable, thus ensuring the driving safety of the entire vehicle. Attached Figure Description

[0030] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0031] Figure 1 This is a flowchart illustrating the accelerator pedal signal reliability diagnosis method based on temperature and vehicle speed according to the present invention.

[0032] Figure 2 This is a schematic diagram illustrating the principle of the accelerator pedal signal reliability diagnosis method based on temperature and vehicle speed of the present invention. Detailed Implementation

[0033] To clearly and completely describe the technical solution and its specific working process of the present invention, the specific embodiments of the present invention are as follows, in conjunction with the accompanying drawings:

[0034] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0036] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0037] Example 1

[0038] like Figure 1 As shown, this embodiment provides a method for diagnosing the reliability of accelerator pedal signals based on temperature and vehicle speed, specifically including the following steps:

[0039] S1. Acquire relevant output signals from the accelerator pedal;

[0040] The output signals of the accelerator pedal include: the voltage of the 5V power supply of the first accelerator pedal sensor, the voltage of the 5V power supply of the second accelerator pedal sensor, the first accelerator pedal signal S1, the second accelerator pedal signal S2, the accelerator pedal resistance temperature, and the real-time vehicle speed.

[0041] The accelerator pedal resistance temperature is measured and collected by a temperature sensor installed on the pedal structure; the real-time vehicle speed is the vehicle speed calculated by the ABS collecting the wheel speed.

[0042] S2. Determine whether the relevant output signals of the accelerator pedal are normal;

[0043] If the voltage of the 5V power supply of the first accelerator pedal sensor or the 5V power supply of the second accelerator pedal sensor is less than the minimum supply voltage, or if the voltage of the 5V power supply of the first accelerator pedal sensor or the 5V power supply of the second accelerator pedal sensor is greater than the maximum supply voltage, then an abnormal supply voltage fault is determined to exist.

[0044] If the first accelerator pedal signal or the second accelerator pedal signal is less than the minimum signal voltage, or if the first accelerator pedal signal or the second accelerator pedal signal is greater than the maximum signal voltage, then an abnormal signal voltage fault is determined to exist.

[0045] S3. Determine whether the relevant output signal of the accelerator pedal is unreliable;

[0046] a: If the accelerator pedal resistance temperature is lower than the minimum rated temperature or higher than the maximum rated temperature, then an unreliable signal fault is confirmed.

[0047] When the resistance temperature exceeds the minimum (TBD calibration value, which can be preset to -40℃) or the maximum (TBD calibration value, which can be preset to 70℃) value, it will be judged as a fault state, and the controller will perform corresponding fault actions, such as limiting vehicle speed, limiting torque, or entering limp state.

[0048] b: When the real-time vehicle speed is 0 < V < V1, if |S1-kS2| > the first maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault.

[0049] c: When the real-time vehicle speed is V1 < V < V2, if |S1-kS2| > the second maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault.

[0050] d: When the real-time vehicle speed is V > V2, if |S1-kS2| > the third maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault.

[0051] Vehicle speed is divided into low, medium, and high ranges using V1 (TBD calibration value, preset to 20km / h) and V2 (TBD calibration value, preset to 60km / h). To better ensure driver safety at these different speed ranges, the higher the speed range, the more stringent the diagnostics should be, and the smaller the maximum error calibration value should be (if considering fault actions, to ensure driver safety, the higher the speed range, the milder the fault action). That is, the third maximum error calibration value > the second maximum error calibration value > the first maximum error calibration value. The error calibration values ​​1, 2, and 3 (TBD calibration values, preset to 1.5V, 0.7V, and 0.5V) of the two signals will also be different accordingly.

[0052] The accelerator pedal resistance temperature T is collected by a newly added temperature sensor at the pedal. Since temperature affects the resistance value, and the pedal opening is determined by voltage division, the resistors used by different manufacturers will vary. The temperature coefficient y needs to be determined based on the resistance characteristics of the actual vehicle's pedal and through actual vehicle calibration. The preset values ​​for the temperature coefficient y and the accelerator pedal resistance temperature T are shown in Table 1.

[0053] Table 1 shows the relationship between the temperature coefficient y and the accelerator pedal resistance temperature T.

[0054] Accelerator pedal resistance temperature T (°C) -40 -30 -20 -10 0 10 20 30 40 50 Temperature coefficient y y1 y2 y3 y4 y5 y6 y7 y8 y9 y10

[0055] S4. If it is determined that the relevant output signal of the accelerator pedal is abnormal or unreliable, the controller should trigger the corresponding torque limit, vehicle speed limit, function limit, limp-drive and other related safety handling mechanisms.

[0056] Example 2

[0057] This embodiment provides a reliability diagnostic system for accelerator pedal signals based on temperature and vehicle speed, including a vehicle controller, an accelerator pedal, an accelerator pedal resistance and temperature sensor, and an EPS controller. The vehicle controller (VCU) is connected to the accelerator pedal and the accelerator pedal resistance and temperature sensor via hard wiring. It collects two power input signals, two accelerator pedal signals, and the accelerator pedal resistance and temperature from the accelerator pedal sensor, and collects the vehicle speed signal sent by the EPS controller via the CAN bus. It then analyzes the accelerator pedal signal in the current state and determines the rationality of the signal.

[0058] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0059] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0060] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for diagnosing the reliability of accelerator pedal signals based on temperature and vehicle speed, characterized in that, Specifically, the steps include the following: S1. Acquire relevant output signals from the accelerator pedal; S2. Determine whether the relevant output signals of the accelerator pedal are normal; S3. Determine whether the relevant output signal of the accelerator pedal is unreliable; S4. If it is determined that the relevant output signal of the accelerator pedal is abnormal or unreliable, the controller should trigger the corresponding safety processing mechanism. The output signals of the accelerator pedal include: the voltage of the 5V power supply of the first accelerator pedal sensor, the voltage of the 5V power supply of the second accelerator pedal sensor, the first accelerator pedal signal S1, the second accelerator pedal signal S2, the accelerator pedal resistance temperature, and the real-time vehicle speed. Step S3 specifically includes the following: a: If the accelerator pedal resistance temperature is lower than the minimum rated temperature or higher than the maximum rated temperature, then an unreliable signal fault is confirmed. b: When the real-time vehicle speed is 0 < V < V1, if |S1-kS2| > the first maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault. c: When the real-time vehicle speed is V1 < V < V2, if |S1-kS2| > the second maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault. d: When the real-time vehicle speed is V > V2, if |S1-kS2| > the third maximum error calibration value * temperature coefficient y, then it is determined that there is a signal unreliability fault. Where V is the real-time vehicle speed, and V1 and V2 are calibration values ​​obtained through calibration.

2. The accelerator pedal signal reliability diagnosis method based on temperature and vehicle speed as described in claim 1, characterized in that, The accelerator pedal resistance temperature is measured and collected by a temperature sensor installed on the pedal structure; the real-time vehicle speed is the vehicle speed calculated by the ABS collecting the wheel speed.

3. The accelerator pedal signal reliability diagnosis method based on temperature and vehicle speed as described in claim 1, characterized in that, Step S2 specifically includes the following: If the voltage of the 5V power supply of the first accelerator pedal sensor or the 5V power supply of the second accelerator pedal sensor is less than the minimum supply voltage, or if the voltage of the 5V power supply of the first accelerator pedal sensor or the 5V power supply of the second accelerator pedal sensor is greater than the maximum supply voltage, then an abnormal supply voltage fault is determined to exist. If the first accelerator pedal signal or the second accelerator pedal signal is less than the minimum signal voltage, or if the first accelerator pedal signal or the second accelerator pedal signal is greater than the maximum signal voltage, then an abnormal signal voltage fault is determined to exist.

4. The accelerator pedal signal reliability diagnosis method based on temperature and vehicle speed as described in claim 1, characterized in that, The temperature coefficient y has the following relationship with the accelerator pedal resistance temperature T, as shown in Table 1; Table 1 shows the relationship between the temperature coefficient y and the accelerator pedal resistance temperature T.

5. A temperature and vehicle speed-based accelerator pedal signal reliability diagnostic system, used to implement the diagnostic method as described in claim 1, characterized in that, It includes a vehicle controller, accelerator pedal, accelerator pedal resistance and temperature sensor, and EPS controller. The vehicle controller (VCU) is connected to the accelerator pedal and accelerator pedal resistance and temperature sensor via hard wiring. It collects two power input signals, two accelerator pedal signals, and accelerator pedal resistance and temperature from the accelerator pedal sensor, and collects the vehicle speed signal sent by the EPS controller via the CAN bus. It analyzes the accelerator pedal signal in the current state and determines the rationality of the signal.

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