Electronic rearview mirror control system based on function safety and control method thereof

Abstract

The invention belongs to the field of automobile control, and particularly relates to an electronic rearview mirror control system based on functional safety and a control method thereof. The electronic rearview mirror system comprises a sensor, a controller and an actuator. And corresponding fault processing is carried out based on different fault types obtained through functional safety HAZOP analysis. According to the electronic rearview mirror, high reliability and high safety of the electronic rearview mirror are guaranteed through the redundant camera, and a certain rearview function can be guaranteed when the camera of the electronic rearview mirror breaks down. And obtaining an electronic rearview mirror system safety target and an ASIL level based on functional safety analysis, and exporting a safety demand. Based on functional safety design, the safety performance of the system is effectively improved, an auxiliary view is provided when the electronic rearview mirror system fails, and the situation that no view exists completely when the system fails can be avoided to a certain extent.

Description

Technical Field

[0001] The present invention belongs to the field of automobile control, and in particular relates to an electronic rearview mirror control system based on functional safety and a control method thereof. Background Art

[0002] With the development of vehicle intelligence, the disadvantages of traditional rearview mirrors, such as poor vision caused by foggy and rainy weather, insufficient light, and frequent alternation of light and dark, have also been solved through the popularization of electronic rearview mirrors. The electronic rearview mirror captures the image around the vehicle through the camera and transmits it to the display screen in real time for the driver to watch, thereby greatly expanding the field of vision and eliminating blind spots. The existing electronic rearview mirror field of vision display control system still has some shortcomings in module integration, data transmission, and functional improvement. However, as an important safety-related system, the electronic rearview mirror is subject to unacceptable risks caused by system and random failures due to the inherent nature of the electrical system itself. For example, some systems have delayed or distorted image display due to poor communication between modules or insufficient data processing capabilities; some systems have multiple functions, but the operation is complicated and not user-friendly, which affects the driver's experience. At present, the risks caused by system or random failure of electronic rearview mirrors are increasing day by day, and a single electronic rearview mirror cannot continue to provide effective vision after failure. Summary of the invention

[0003] In view of the above problems, the present invention uses the cabin parking controller as the electronic rearview mirror controller based on the cabin parking integrated design, and borrows the parking assistance rear camera and the cabin central control screen to provide an electronic rearview mirror control system and control method based on functional safety. When the electronic rearview mirror system fails, part of the field of view is still retained to improve the system safety. The specific technical solution is as follows: A functional safety-based electronic rearview mirror control system, the electronic rearview mirror system includes three parts: a sensor, a controller and an actuator; the sensor includes a left electronic rearview mirror camera, a right electronic rearview mirror camera and a rear camera; the controller is provided with a function control module and an image processing module; the actuator is provided with a central control screen, a left electronic rearview mirror screen and a right electronic rearview mirror screen; the sensor transmits the collected image to the controller, and the controller performs image processing and outputs the image to the left electronic rearview mirror screen and the right electronic rearview mirror screen of the actuator.

[0004] Furthermore, the controller may also be provided with a watchdog module.

[0005] Using the control method of the aforementioned control system, including determining functional safety requirements and fault analysis and processing, The functional safety requirements include: (1) Confirm the failure mode, including delayed or stuck electronic rearview mirror imaging, inverted electronic rearview mirror imaging, reversed left and right electronic rearview mirror imaging (left displays right, right displays left), incomplete or lost electronic rearview mirror imaging; (2) According to the requirements of ISO 26262 functional safety standard, HARA analysis is conducted from the three aspects of controllability C, severity S, and exposure E combined with the main operating scenarios of the function to determine the safety goals and ASIL levels, and obtain the safety goal SG; (3) Based on the safety goal SG analyzed by HARA, the functional safety requirement FSR is derived through fault tree FTA analysis; The steps of fault analysis processing are as follows: (1) Through the perception fusion technology, the image of the rear camera is cross-checked with the image of the left electronic rearview mirror and the right electronic rearview mirror camera to determine whether the camera image of the electronic rearview mirror system is correct; (2) If they are consistent, the function is normal; (3) If it is detected that the image of the left / right electronic rearview mirror camera is inconsistent with the image of the rear camera, but the image of the right / left electronic rearview mirror camera is consistent with the image of the rear camera, it is determined that the left / right electronic rearview mirror camera is faulty, and the image of the rear camera is sheared and deformed to cover the erroneous image to provide a temporary field of view for the driver, and the driver is alerted through the vehicle alarm system to remind the driver to find a nearby repair station for repair in time; (4) If the images are inconsistent, the rearview mirror camera image will be processed and displayed on the vehicle's central control screen, and the vehicle alarm system will alert the driver to promptly find a nearby repair station for repair.

[0006] Furthermore, if the electronic rearview mirror controller is provided with a watchdog module, the main control module and the image processing module are monitored by the watchdog module, and if a fault occurs, the controller is restarted by controlling the power supply module.

[0007] Furthermore, the fault analysis processing step also includes: (5) The controller collects the images of the left and right electronic rearview mirror screens of the actuator and compares them with the images collected by the rear camera through perception fusion technology; (6) If the comparison result on one side is inconsistent, the electronic rearview mirror screen display on the inconsistent side will be cut off, and the rear camera image will be processed and displayed on the vehicle's central control screen. The vehicle alarm system will alert the driver to find a nearby repair station for repair in time; (7) If the comparison results on both sides are inconsistent, the rearview mirror camera image will be processed and displayed on the vehicle's central control screen, and the driver will be alerted through the vehicle alarm system to remind the driver to find a nearby repair station for repair in time.

[0008] The present invention uses redundant cameras to ensure the high reliability and high safety of the electronic rearview mirror, and can also ensure a certain rearview function when the electronic rearview mirror camera fails. Based on functional safety analysis, the safety goals and ASIL levels of the electronic rearview mirror system are obtained and safety requirements are derived. Based on functional safety design, the present invention effectively improves the safety performance of the system, and provides an auxiliary field of view when the electronic rearview mirror system fails, which can avoid the situation of no field of view when the system fails to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 A schematic diagram of the structure of the electronic rearview mirror control system of the present invention; Figure 2 A schematic diagram of a process for determining functional safety requirements in the method of the present invention; Figure 3 Schematic diagram of the fault analysis process of the present invention. DETAILED DESCRIPTION

[0010] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0011] An electronic rearview mirror control system based on functional safety Figure 1 As shown, the electronic rearview mirror system includes three parts: sensors, controllers and actuators; the sensors include left electronic rearview mirror cameras, right electronic rearview mirror cameras and rear cameras; the controller is provided with a function control module and an image processing module; the actuator is provided with a central control screen, a left electronic rearview mirror screen and a right electronic rearview mirror screen; the sensor transmits the collected image to the controller, and the controller processes the image and outputs it to the left electronic rearview mirror screen and the right electronic rearview mirror screen of the actuator. The controller may also be provided with a watchdog module.

[0012] Using the control method of the aforementioned control system, including determining functional safety requirements and fault analysis and processing, Determining functional safety requirements includes: specific processes such as Figure 2 As shown: (1) Confirm the failure mode, including delayed or stuck electronic rearview mirror imaging, inverted electronic rearview mirror imaging, reversed left and right electronic rearview mirror imaging (left displays right, right displays left), incomplete or lost electronic rearview mirror imaging; (2) According to the requirements of ISO 26262 functional safety standard, HARA analysis is conducted from the three aspects of controllability C, severity S, and exposure E combined with the main operating scenarios of the function to determine the safety goals and ASIL levels, and the safety goal SG is obtained, as shown in the following table; SG describe ASIL Rating FTTI SG1 Avoid unexpected electronic rearview mirror imaging jams B 1000ms SG2 Avoid unexpected electronic rearview mirror image reversal B 1000ms SG3 Avoid unexpected electronic rearview mirror image inversion A 1000ms SG4 Avoid unexpected electronic rearview mirror imaging incompleteness or loss QM - (3) Based on the safety goal SG analyzed by HARA, the functional safety requirement FSR is derived through fault tree FTA analysis, as shown in the following table; NO. describe ASIL Level FSR01 The left electronic rearview mirror camera should send imaging information correctly B FSR02 The right electronic rearview mirror camera should send imaging information correctly B FSR03 The rearview mirror camera should send imaging information correctly QM FSR04 The electronic rearview mirror controller should be able to correctly process the left and right electronic rearview mirror imaging B FSR05 The electronic rearview mirror controller should be able to diagnose and handle left and right electronic rearview mirror camera imaging failures B FSR06 If the electronic rearview mirror controller diagnoses and processes the imaging failure of the left and right electronic rearview mirror cameras, it will send a warning message to the driver B FSR07 If the electronic rearview mirror controller diagnoses a left / right electronic rearview mirror camera fault, it should be able to correctly process the rear camera image and overwrite the faulty electronic rearview mirror camera image. QM FSR08 If the electronic rearview mirror controller diagnoses a fault in both the left and right electronic rearview mirror cameras, it should be able to correctly process the rear camera image and display it on the vehicle's central control screen. QM FSR09 The vehicle's central control screen should correctly display the camera image QM FSR10 The left and right electronic rearview mirror displays should correctly display the camera images B FSR11 The vehicle's central control screen should correctly display the alarm information B The steps of fault analysis processing are as follows: Figure 3 shown.

[0013] (1) Through the perception fusion technology, the image of the rear camera is cross-checked with the image of the left electronic rearview mirror and the right electronic rearview mirror camera to determine whether the camera image of the electronic rearview mirror system is correct; (2) If they are consistent, the function is normal; (3) If it is detected that the image of the left / right electronic rearview mirror camera is inconsistent with the image of the rear camera, but the image of the right / left electronic rearview mirror camera is consistent with the image of the rear camera, it is determined that the left / right electronic rearview mirror camera is faulty, and the image of the rear camera is sheared and deformed to cover the erroneous image to provide a temporary field of view for the driver, and the driver is alerted through the vehicle alarm system to remind the driver to find a nearby repair station for repair in time; (4) If the images are inconsistent, the rearview mirror camera image will be processed and displayed on the vehicle's central control screen, and the vehicle alarm system will alert the driver to promptly find a nearby repair station for repair.

[0014] If the electronic rearview mirror controller is provided with a watchdog module, the main control module and the image processing module are monitored by the watchdog module. If a fault occurs, the controller is restarted by controlling the power supply module.

[0015] The fault analysis processing steps also include: (5) The controller collects the images of the left and right electronic rearview mirror screens of the actuator and compares them with the images collected by the rear camera through perception fusion technology; (6) If the comparison result on one side is inconsistent, the electronic rearview mirror screen display on the inconsistent side will be cut off, and the rear camera image will be processed and displayed on the vehicle's central control screen. The vehicle alarm system will alert the driver to find a nearby repair station for repair in time; (7) If the comparison results on both sides are inconsistent, the rearview mirror camera image will be processed and displayed on the vehicle's central control screen, and the driver will be alerted through the vehicle alarm system to remind the driver to find a nearby repair station for repair in time.

[0016] The above describes in detail the preferred implementation of this patent, but this patent is not limited to the above implementation. Various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of this patent.

Claims

1. An electronic rearview mirror control system based on functional safety, characterized in that: The electronic rearview mirror system includes three parts: a sensor, a controller and an actuator; the sensor includes a left electronic rearview mirror camera, a right electronic rearview mirror camera and a rear camera; the controller is provided with a function control module and an image processing module; the actuator is provided with a central control screen, a left electronic rearview mirror screen and a right electronic rearview mirror screen; the sensor transmits the collected image to the controller, and after the controller performs image processing, the image is output to the left electronic rearview mirror screen and the right electronic rearview mirror screen of the actuator.

2. The electronic rearview mirror control system based on functional safety according to claim 1, characterized in that: The controller may also be provided with a watchdog module.

3. The control method of the electronic rearview mirror control system according to claim 2, characterized in that: Including determining functional safety requirements and fault analysis processing, The functional safety requirements include: (1) Confirm the failure mode, including delayed or stuck electronic rearview mirror imaging, inverted electronic rearview mirror imaging, reversed left and right electronic rearview mirror imaging, incomplete or lost electronic rearview mirror imaging; (2) According to the requirements of ISO 26262 functional safety standard, HARA analysis is conducted from the three aspects of controllability C, severity S, and exposure E combined with the main operating scenarios of the function to determine the safety goals and ASIL levels, and obtain the safety goal SG; (3) Based on the safety goal SG analyzed by HARA, the functional safety requirement FSR is derived through fault tree FTA analysis; The steps of fault analysis processing are as follows: (1) Through the perception fusion technology, the image of the rear camera is cross-checked with the image of the left electronic rearview mirror and the right electronic rearview mirror camera to determine whether the camera image of the electronic rearview mirror system is correct; (2) If they are consistent, the function is normal; (3) If it is detected that the image of the left / right electronic rearview mirror camera is inconsistent with the image of the rear camera, but the image of the right / left electronic rearview mirror camera is consistent with the image of the rear camera, it is determined that the left / right electronic rearview mirror camera is faulty, and the image of the rear camera is sheared and deformed to cover the erroneous image to provide a temporary field of view for the driver, and the driver is alerted through the vehicle alarm system to remind the driver to find a nearby repair station for repair in time; (4) If the images are inconsistent, the rearview mirror camera image will be processed and displayed on the vehicle's central control screen, and the vehicle alarm system will alert the driver to promptly find a nearby repair station for repair.

4. The control method according to claim 3, characterized in that: If the electronic rearview mirror controller is provided with a watchdog module, the main control module and the image processing module are monitored by the watchdog module. If a fault occurs, the controller is restarted by controlling the power supply module.

5. The control method according to claim 3, characterized in that: The fault analysis processing steps also include: (5) The controller collects the images of the left and right electronic rearview mirror screens of the actuator and compares them with the images collected by the rear camera through perception fusion technology; (6) If the comparison result on one side is inconsistent, the electronic rearview mirror screen display on the inconsistent side will be cut off, and the rear camera image will be processed and displayed on the vehicle's central control screen. The vehicle alarm system will alert the driver to find a nearby repair station for repair in time; (7) If the comparison results on both sides are inconsistent, the rearview mirror camera image will be processed and displayed on the vehicle's central control screen, and the driver will be alerted through the vehicle alarm system to remind the driver to find a nearby repair station for repair in time.

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