Failure judgment method and device for brake-by-wire system of self-driving mine car

Abstract

The embodiment of the invention provides a failure judgment method and device for a brake-by-wire system of an automatic driving mine car, and relates to the technical field of vehicle control. The method comprises the steps of recording a first moment when an emergency braking instruction is issued to the self-driving mine car, obtaining a chassis speed and a positioning speed of the mine car at a second moment obtained based on a preset delay duration, obtaining a chassis speed and a positioning speed at a target moment, determining a target acceleration according to the chassis speeds and the positioning speeds at the two moments, and sending the target acceleration to the self-driving mine car. And determining whether the brake-by-wire system fails or not according to the target acceleration and a preset reference acceleration. Based on the method provided by the embodiment of the invention, the target acceleration of the mine car is determined by using multiple speed parameters subjected to delay time compensation, and the failure judgment of the brake-by-wire system is performed based on the target acceleration, so that the accuracy and reliability of the judgment result are improved.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle control. Specifically, the present application relates to a method and device for judging the failure of a by-wire braking system of an autonomous mining truck. Background Art

[0002] A by-wire braking system (BBW) is a control system that controls the braking process of a vehicle through electrical signals.

[0003] In the harsh working environment of an unmanned mining truck, the by-wire braking system will gradually fail as the working hours of the vehicle increase, and its failure speed is much faster than that of a traditional passenger car. Therefore, there is an urgent need for a counting scheme that can timely and accurately judge whether the by-wire braking system of the vehicle fails to ensure the safe operation of the mining truck under complex working conditions. Summary of the Invention

[0004] Embodiments of the present application provide a method, device, electronic device, computer-readable storage medium, and computer program product for judging the failure of a by-wire braking system of an autonomous mining truck. To achieve the purpose of accurately judging whether the by-wire braking system of the autonomous mining truck fails, the technical solutions provided by the embodiments of the present application are as follows: According to one aspect of the embodiments of the present application, a method for judging the failure of a by-wire braking system of an autonomous mining truck is provided. The method includes: When a preset emergency braking condition is satisfied, an emergency braking instruction is sent to the by-wire braking system of the autonomous mining truck, and the first moment when the emergency braking instruction is sent is recorded; Obtain the first chassis speed and the first positioning speed of the autonomous mining truck at a second moment, where the second moment is a moment after a preset delay duration starting from the first moment; Obtain the second chassis speed and the second positioning speed of the autonomous mining truck at a target moment, where the target moment includes the moment when the vehicle speed is first 0 after the emergency braking instruction is sent, or the moment after the preset delay duration after a cancellation instruction is sent, and the cancellation instruction is used to cancel the emergency braking instruction; According to the second chassis speed and the first chassis speed, determine the first acceleration of the autonomous mining truck from the second moment to the target moment; according to the second positioning speed and the first positioning speed, determine the second acceleration of the autonomous mining truck from the second moment to the target moment; according to the first acceleration and the second acceleration, determine the target acceleration; According to the target acceleration and a preset reference acceleration, determine whether the by-wire braking system fails.

[0005] According to another aspect of the embodiments of the present application, there is provided a failure determination device for a wire braking system of an autonomous mining truck, the device comprising: An emergency braking instruction issuing module, configured to issue an emergency braking instruction to the wire braking system of the autonomous mining truck when a preset emergency braking condition is met, and record a first moment when the emergency braking instruction is issued; A first parameter acquisition module, configured to acquire a first chassis speed and a first positioning speed of the autonomous mining truck at a second moment, where the second moment is a moment after a preset delay duration starting from the first moment; A second parameter acquisition module, configured to acquire a second chassis speed and a second positioning speed of the autonomous mining truck at a target moment, where the target moment includes a moment when the vehicle speed is first 0 after the emergency braking instruction is issued, or a moment after a preset delay duration after a cancellation instruction is issued, and the cancellation instruction is used to cancel the emergency braking instruction; A target acceleration determination module, configured to determine a first acceleration of the autonomous mining truck from the second moment to the target moment according to the second chassis speed and the first chassis speed; determine a second acceleration of the autonomous mining truck from the second moment to the target moment according to the second positioning speed and the first positioning speed; determine a target acceleration according to the first acceleration and the second acceleration; A failure determination module, configured to determine whether the wire braking system fails according to the target acceleration and a preset reference acceleration.

[0006] Optionally, the target acceleration determination module may be configured to acquire a first weight of the first acceleration and a second weight of the second acceleration; Perform weighted summation on the first acceleration and the second acceleration according to the first weight and the second weight to obtain a target acceleration.

[0007] Optionally, the failure determination module may be configured to adjust the reference acceleration by using a preset first adjustment coefficient to obtain a third acceleration, where the first adjustment coefficient is less than 1 and greater than 0; When the target acceleration is greater than or equal to the third acceleration, determine that the failure state of the wire braking system is not failed; When the target acceleration is less than or equal to the third acceleration, determine that the failure state of the wire braking system is failed.

[0008] Optionally, the failure determination module may be configured to adjust the third acceleration by using a preset second adjustment coefficient to obtain a fourth acceleration, where the second adjustment coefficient is less than 1 and greater than 0; When the target acceleration is greater than or equal to the fourth acceleration, determine that the failure degree of the wire control braking system is a minor failure; When the target acceleration is equal to or less than the fourth acceleration, determine that the failure degree of the wire control braking system is a severe failure.

[0009] Optionally, the failure judgment module can be used to determine the current load state of the autonomous mining truck, and the current load state includes an unloaded state or a non-unloaded state; Obtain a first adjustment coefficient corresponding to the current load state, where the first adjustment coefficient corresponding to the non-unloaded state is less than the first adjustment coefficient corresponding to the unloaded state; Adjust the reference acceleration by using the first adjustment coefficient corresponding to the current load state to obtain the third acceleration.

[0010] Optionally, the device further includes: A failure handling module, configured to send a speed reduction instruction to the wire control braking system and display an alarm code if it is determined that the failure degree of the wire control braking system is a minor failure; If the failure degree of the wire control braking system is a severe failure, control the autonomous mining truck to decelerate through a hydraulic retarder and display an alarm code.

[0011] According to another aspect of the embodiments of the present application, there is provided an electronic device, including a memory, a processor, and a computer program stored on the memory, where the processor executes the computer program to implement the steps of the method provided in any optional embodiment of the present application.

[0012] According to still another aspect of the embodiments of the present application, there is provided a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the method provided in any optional embodiment of the present application are implemented.

[0013] According to one aspect of the embodiments of the present application, there is provided a computer program product, including a computer program, and when the computer program is executed by a processor, the steps of the method provided in any optional embodiment of the present application are implemented.

[0014] The beneficial effects brought by the technical solution provided by the embodiment of the present application are as follows: By introducing a variety of parameters and conducting a failure analysis on the wire control braking system of the mine car, the accuracy of the failure judgment of the wire control braking system is improved, and the inaccuracy of the judgment result caused by relying solely on a single index is avoided. In addition, considering the delay of the wire control braking system in braking response, therefore, by presetting a delay duration to perform time compensation on the moment when the vehicle speed is collected, based on the positioning speed and chassis speed of the mine car when the wire control braking system truly starts to respond to braking, the target acceleration of the mine car is determined, which improves the accuracy and reliability of the failure judgment of the wire control braking system of the mine car. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for the description in the embodiments of the present application.

[0016] Figure 1 It is a schematic flow chart of a method for judging the failure of a wire control braking system for realizing an autonomous driving mine car provided by an embodiment of the present application; Figure 2 It is a schematic flow chart of another method for judging whether the wire control braking system fails provided by an embodiment of the present application; Figure 3 It is a schematic flow chart of determining the failure degree of the wire control braking system provided by an embodiment of the present application; Figure 4 It is a schematic flow chart of another method for judging whether the wire control braking system fails provided by an embodiment of the present application; Figure 5 It is a module diagram of the failure judgment of the wire control braking system of an autonomous driving mine car provided by an embodiment of the present application; Figure 6 It is a schematic structural diagram of a device for judging the failure of the wire control braking system of an autonomous driving mine car provided by an embodiment of the present application; Figure 7 It is a schematic structural diagram of the corresponding electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The following describes the embodiments of the present application with reference to the drawings in the present application. It should be understood that the embodiments described below in conjunction with the drawings are exemplary descriptions for explaining the technical solutions of the embodiments of the present application, and do not constitute a limitation to the technical solutions of the embodiments of the present application.

[0018] Those skilled in the art can understand that, unless specifically stated, the singular forms "a", "an", "the" and "said" used herein may also include the plural forms. It should be further understood that the terms "comprising" and "including" used in the embodiments of the present application mean that the corresponding features can be implemented as the presented features, information, data, steps, operations, elements and / or components, but do not exclude the implementation of other features, information, data, steps, operations, elements, components and / or their combinations supported by the technical field of the present application, etc. It should be understood that when we say an element is "connected" or "coupled" to another element, this element can be directly connected or coupled to the other element, or it can mean that this element and the other element establish a connection relationship through an intermediate element. In addition, the "connection" or "coupling" used herein can include wireless connection or wireless coupling. The term "and / or" used herein indicates at least one of the items defined by this term. For example, "A and / or B" or "A, B" indicates that it is implemented as "A", or implemented as "B", or implemented as "A and B". When describing multiple (two or more) items, if the relationship between the multiple items is not clearly defined, the multiple items can refer to one, multiple or all of the multiple items. For example, for the description of "parameter A includes A1, A2, A3", it can be implemented that parameter A includes A1 or A2 or A3, and it can also be implemented that parameter A includes at least two of the three items of parameter A1, A2, A3.

[0019] With the rapid development of driverless technology, the automation level of heavy vehicles such as mining trucks has been continuously improved. As a core component of driverless mining trucks, the reliability and safety of the wire control braking system are directly related to the overall performance and working efficiency of the vehicle. However, in harsh working environments such as mining trucks, due to long-term high-load operation, the wire control braking system is prone to brake failure, seriously threatening the safety of the vehicle and the working environment.

[0020] The traditional failure judgment method for the wire control braking system of mining trucks mainly relies on a single index for judgment, resulting in inaccurate and unreliable judgment results. In addition, the response delay of the wire control braking system is an important factor affecting the performance of the braking system. The traditional method fails to effectively consider this delay, resulting in a large deviation between the determined braking acceleration and the actual value, affecting the accuracy of failure judgment.

[0021] The embodiments of the present application provide a failure judgment method for the wire control braking system of an autonomous driving mining truck. The embodiments of the present application comprehensively consider factors such as the response delay of the wire control braking system and the influence of multiple parameters. Through the response delay time compensation mechanism and multi-parameter comprehensive analysis, it realizes real-time and accurate judgment of the failure of the vehicle braking system, significantly improves the accuracy, reliability and safety of the failure judgment of the wire control braking system of the autonomous driving mining truck, and provides a strong guarantee for the safe operation of the autonomous driving mining truck.

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of the embodiments of this application and the technical effects produced by the technical solutions of this application will be described below through the description of several exemplary embodiments. It should be noted that the following embodiments can be referenced, borrowed, or combined with each other. For the same terms, similar features, and similar implementation steps in different embodiments, they will not be repeatedly described.

[0023] Figure 1 The figure is a schematic flowchart of a method for judging the failure of a wire braking system for an autonomous driving mining truck provided by an embodiment of this application. Among them, this method is executed by an electronic control unit (ECU) for an autonomous driving mining truck. As Figure 1 shown, this method includes S101 to S106: S101: When a preset emergency braking condition is met, send an emergency braking instruction to the wire braking system of the autonomous driving mining truck, and record the first moment when the emergency braking instruction is sent; obtain the first chassis speed and the first positioning speed of the autonomous driving mining truck at a second moment, where the second moment is the moment after a preset delay duration starting from the first moment.

[0024] When an autonomous driving mining truck performs various operations, various emergencies may occur and emergency braking is required. When a preset emergency braking condition is met, the ECU can send an emergency braking instruction to the wire braking system of the autonomous driving mining truck, so that the wire braking system of the autonomous driving mining truck responds to the emergency braking instruction and performs emergency braking on the autonomous driving mining truck.

[0025] For example, when the road surface where the autonomous driving mining truck is traveling is relatively slippery, the wheels of the autonomous driving mining truck may slip for a long time. To ensure the safety of the autonomous driving mining truck, the ECU can send an emergency braking instruction to the wire braking system of the autonomous driving mining truck to make the autonomous driving mining truck decelerate. Another example is that when the vehicle in front of the mining truck makes an emergency brake, resulting in a rapid reduction in the distance from the mining truck, emergency braking is required to avoid colliding with the vehicle in front.

[0026] The embodiments of this application do not limit the specific preset emergency braking conditions, which can be set as needed. Specifically, the preset emergency braking conditions can include any one or more of the following: the preset emergency braking conditions can include that the continuous duration of wheel slip is greater than a preset duration, an emergency brake occurs to the vehicle in front, and the distance from the vehicle in front is less than a preset distance, an obstacle suddenly appears in front, and the obstacle can be a person, a stone rolled down by an animal, etc.

[0027] It should be noted that the ECU can determine whether the preset emergency braking condition is met based on the perception data sent by various sensors of the mine car, and the embodiments of the present application do not limit this.

[0028] For example, the ECU can monitor the rotational speeds of each wheel through a wheel speed sensor, compare the rotational speeds between each wheel. If the rotational speed difference between each wheel is greater than a preset difference and the duration is greater than a preset duration, it indicates that the mine car meets the preset emergency braking condition. The distance to the vehicle ahead is monitored through sensors such as radar to determine whether the preset emergency braking condition is met. Images captured by the camera of the mine car, radio waves sent by the radar and the received reflected signals, infrared radiation images detected by the infrared sensor, etc. are used to detect whether there are unknown obstacles, and then determine whether the preset emergency braking condition is met.

[0029] When the ECU issues an emergency braking instruction, it can also record the first moment when the emergency braking instruction is issued. Combining this first moment with the preset delay duration, a more accurate vehicle speed of the mine car when the electronic brake control system responds to the emergency braking instruction can be obtained, thereby improving the accuracy of the determined target acceleration of the mine car and the accuracy of judging whether the electronic brake control system fails.

[0030] Specifically, the embodiments of the present application consider that there is a time delay in the electronic brake control system receiving the emergency braking instruction issued by the ECU and operating to brake the mine car. Therefore, by compensating for the duration delay of responding to the emergency braking instruction, a more accurate vehicle speed of the mine car at the moment when the electronic brake control system starts to brake is determined. Therefore, the ECU can obtain the vehicle speed of the mine car corresponding to the moment after compensating for the time delay by the speed acquisition module to obtain a more accurate actual acceleration.

[0031] That is, the ECU can obtain the first chassis speed and the first positioning speed of the autonomous mine car at the second moment. The second moment starts from the first moment and is the moment after a preset delay duration. In other words, the second moment = preset delay duration + first moment .

[0032] Among them, the preset delay duration can be an empirical value or an experimental value. The first chassis speed is obtained by the chassis speed acquisition module, and the first positioning speed is obtained by the positioning speed acquisition module. The chassis speed acquisition module can be a wheel speed sensor, and the wheel speed sensor can determine the chassis speed by determining the number of turns of the wheel in a unit time (equivalent to the distance in a unit time). The positioning speed acquisition module can be a Global Positioning System (GPS), or a module obtained by combining GPS with an Inertial Measurement Unit (IMU). The embodiments of the present application do not limit this. The first chassis speed and the first positioning speed can be used to subsequently determine whether the wire control braking system fails.

[0033] The embodiments of the present application consider the defect of the response delay of the wire control braking system, compensate for the response delay time, and realize determining the target acceleration of the mining truck by using the speed of the mining truck at the moment when the wire control braking system truly starts to respond to braking, improving the accuracy and reliability of the braking system failure determination.

[0034] S102: Obtain the second chassis speed and the second positioning speed of the autonomous mining truck at the target moment.

[0035] Among them, the target moment includes the moment when the vehicle speed is first 0 m / s after the emergency braking instruction is issued, or the moment after a preset delay duration after the cancellation instruction is issued. The cancellation instruction is used to cancel the emergency braking instruction.

[0036] It can be understood that the data sensed by various sensors may be incorrect, resulting in misjudgment by the ECU. The ECU will judge whether the mining truck meets the preset emergency braking conditions according to a preset period. Then, when a misjudgment occurs in the first period, the misjudgment situation in the first period can be detected in the second period, and a cancellation instruction is sent to the wire control braking system of the mining truck to enable the mining truck to drive normally. For example, in the first period, using the pictures taken by the camera of the mining truck, it is detected that there is an obstacle within a preset distance in front, and an emergency braking instruction is sent to the wire control braking system. In the second period, using the pictures taken by the camera of the mining truck again, it is detected that there is no obstacle within the preset distance in front, then a cancellation instruction can be sent to the wire control braking system.

[0037] It is also possible that when the emergency braking instruction is issued, the mining truck meets the preset emergency braking conditions, but after a period of braking, the mining truck does not meet the preset emergency braking conditions, then the ECU can send a cancellation instruction to the wire control braking system. For example, in the first period, it is detected that the vehicle in front is braking emergently. To avoid collision, an emergency braking instruction is sent to the wire control braking system. In the second period, it is detected that the vehicle in front is driving normally, then a cancellation instruction can be sent to the wire control braking system.

[0038] The target moment can also be the moment when the vehicle speed is first 0 m / s. This is because the parameter for judging whether the electronic stability control (ESC) system fails subsequently is the acceleration of the mining truck during the emergency braking duration. If the vehicle speed is already 0 m / s, there is no need for emergency braking. Then, the corresponding emergency braking duration should be from the second moment when the ESC system starts braking to the moment when the vehicle speed is first 0 m / s. If the moment when the vehicle speed is not first 0 m / s is determined as the target moment, then the emergency braking duration (the duration from the second moment to the target moment) determined based on the target moment and the second moment will be longer than the actual emergency braking duration, resulting in a smaller calculated target acceleration, which in turn affects the subsequent judgment of the ESC system failure.

[0039] In other words, the acceleration calculated subsequently is the acceleration during the emergency braking duration. Therefore, the target moment is the moment when the emergency braking ends. The end of the emergency braking can include two situations: the vehicle speed is first 0 m / s and the emergency braking is cancelled. Therefore, one of the moment when the emergency braking is cancelled and the moment when the vehicle speed is 0 m / s can be determined as the target moment.

[0040] It should be noted that the difference between the target moment being the moment when the cancellation instruction is sent to the ESC system and the target moment being the moment when the vehicle speed is first 0 m / s is that the vehicle speed corresponding to the moment when the cancellation instruction is sent to the ESC system is not 0 m / s.

[0041] Then, the ECU can determine the vehicle speed at each moment after the second moment, that is, obtain the chassis speed and the positioning speed at each moment, and perform weighted averaging to obtain the vehicle speed. Since the vehicle speed is obtained by weighted averaging the chassis speed and the positioning speed, the target moment being the moment when the vehicle speed is first 0 m / s means that both the chassis speed and the positioning speed at the target moment are 0 m / s.

[0042] Of course, after the chassis speed and the positioning speed at each moment are obtained, it can also be determined whether the vehicle speed at each moment is 0 m / s by judging whether both the chassis speed and the positioning speed are 0 m / s. Specifically, if at least one of the chassis speed and the positioning speed at this moment is not 0 m / s, it means that the vehicle speed at this moment is not 0 m / s. There is no need to actually calculate the vehicle speed at this moment, saving computing resources.

[0043] It can be understood that when judging whether the vehicle speed is 0 m / s, the chassis speed and the positioning speed have been obtained. If it is determined that the vehicle speed at a certain moment is first 0 m / s, then this moment is determined as the target moment, and the chassis speed and the positioning speed obtained at this moment are respectively determined as the second chassis speed and the second positioning speed.

[0044] If, at the moment after a preset delay duration has elapsed after a cancellation instruction is issued at the target moment, the ECU may first record the moment when the cancellation instruction is issued as the third moment, and take the moment after a preset delay duration from the third moment as the target moment, and obtain the second chassis speed and the second positioning speed of the autonomous mining truck at the target moment.

[0045] S103: Determine the first acceleration of the autonomous mining truck from the second moment to the target moment according to the second chassis speed and the first chassis speed; determine the second acceleration of the autonomous mining truck from the second moment to the target moment according to the second positioning speed and the first positioning speed; determine the target acceleration according to the first acceleration and the second acceleration.

[0046] In the embodiment of the present application, the ECU may determine the first acceleration of the autonomous mining truck from the second moment to the target moment according to the second chassis speed and the first chassis speed. The first acceleration is as follows:

[0047] where is the second chassis speed, is the first chassis speed, is the target moment, is the second moment.

[0048] Determine the second acceleration of the autonomous mining truck from the second moment to the target moment according to the second positioning speed and the first positioning speed. The second acceleration is as follows:

[0049] where is the second positioning speed, is the first positioning speed.

[0050] The ECU may directly determine the average value of the first acceleration and the second acceleration as the target acceleration, or may also obtain the first weight of the first acceleration and the second weight of the second acceleration; perform a weighted sum of the first acceleration and the second acceleration according to the first weight and the second weight to obtain the target acceleration.

[0051]

[0052] where and are the preset first weight and the preset second weight respectively.

[0053] In the embodiments of the present application, by considering various speed parameters, the failure of the electronic brake system of the autonomous mining truck is judged, which improves the accuracy of the judgment result. Moreover, the time used for judgment is the time for actual emergency braking, reducing the error of the determined target acceleration and further improving the accuracy of the judgment result.

[0054] S104: Determine whether the electronic brake system fails according to the target acceleration and the preset reference acceleration.

[0055] Specifically, the ECU can directly determine whether the electronic brake system fails by comparing the magnitude of the target acceleration with the preset reference acceleration. When the target acceleration is greater than the preset reference acceleration, it is determined that the electronic brake system has not failed. When the target acceleration is not greater than the preset reference acceleration, it is determined that the electronic brake system fails. Among them, the reference acceleration can be an empirical value or an experimental value.

[0056] It should be noted that since the acceleration in the embodiments of the present application is used to brake the mining truck, that is, to decelerate the mining truck, the acceleration in the embodiments of the present application is negative. When comparing the accelerations, the absolute values of the accelerations are actually compared. For example, when comparing the target acceleration with the reference acceleration , what is actually compared is with . The subsequent content of acceleration comparison is also to compare the absolute values of the accelerations, which will not be elaborated here.

[0057] In addition, the preset reference acceleration can also be adjusted to obtain an adjusted acceleration, and whether the electronic brake system fails is judged by comparing the adjusted acceleration with the target acceleration.

[0058] Specifically, in the embodiments of the present application, the reference acceleration is adjusted by using a preset first adjustment coefficient to obtain a third acceleration. The first adjustment coefficient is less than 1 and greater than 0 m / s; when the target acceleration is greater than or equal to the third acceleration, it is determined that the failure state of the electronic brake system is not failed; when the target acceleration is less than or equal to the third acceleration, it is determined that the failure state of the electronic brake system is failed.

[0059] It should be noted that when the target acceleration is equal to the third acceleration, it can be determined that the failure state of the electronic brake system is not failed, or it can be determined that the failure state of the electronic brake system is failed. Specifically, only one of the judgment results of not failed and failed can be selected.

[0060] Figure 2 FIG. Figure 2 shows another flow chart for judging whether the electronic brake system fails provided by the embodiments of the present application.

[0061] If the first adjustment coefficient is , then the third acceleration is . If the target acceleration is greater than the third acceleration , it is determined that the failure state of the electronic brake system is not failed. If the target acceleration is not greater than the third acceleration , it is determined that the failure state of the electronic brake system is failed.

[0062] By using a decimal number, which is a positive number, to adjust the reference acceleration, the acceleration for comparison can be further reduced, thereby further restricting the target acceleration and improving the accuracy of the judgment result.

[0063] In the embodiments of the present application, the influence of the failure degree of the electronic brake system on the mine car is also considered. Therefore, the second adjustment parameter is used to classify and determine the failure degree of the electronic brake system, so as to use different control strategies to protect the mine car subsequently.

[0064] Specifically, the ECU can adjust the third acceleration by using a preset second adjustment coefficient to obtain a fourth acceleration. The second adjustment coefficient is less than 1 and greater than 0 m / s². When the target acceleration is greater than or equal to the fourth acceleration, it is determined that the failure degree of the electronic brake system is a mild failure. When the target acceleration is less than or equal to the fourth acceleration, it is determined that the failure degree of the electronic brake system is a severe failure.

[0065] It should be noted that when the target acceleration is equal to the fourth acceleration, it can be determined that the failure state of the electronic brake system is a mild failure, or it can be determined that the failure state of the electronic brake system is a severe failure. Specifically, only one of the mild failure and the severe failure can be selected as the judgment result.

[0066] In addition, the failure degree is related to the braking ability. A mild failure means that the electronic brake system still has braking ability, but the braking ability has decreased compared with that of the non-failed electronic brake system. In the embodiments of the present application, a severe failure means that the electronic brake system does not have braking ability. The braking ability can be determined according to the magnitudes of the target acceleration and the reference acceleration. When the target acceleration is less than the third acceleration but greater than the fourth acceleration, the ECU determines that the electronic brake system still has braking ability, but the braking ability has decreased compared with that of the non-failed electronic brake system. When the target acceleration is not greater than the fourth acceleration, the ECU determines that the electronic brake system does not have braking ability.

[0067] Since the fourth acceleration is obtained by adjusting the third acceleration, and the second adjustment coefficient is a decimal less than 1 and this decimal is positive, the fourth acceleration is less than the third acceleration. It has been previously determined that the target acceleration is less than the third acceleration (at this time, the determination result with the target acceleration equal to the third acceleration is determined as the non-failure state of the wire control braking system). The wire control braking system of the mine car has failed. Then, subsequently, the target acceleration is compared with the fourth acceleration which is less than the third acceleration, and the mine car is also in a failure state, but it may be a mild failure or a severe failure. The failure degree can be specifically determined according to the result of the fourth acceleration and the target acceleration.

[0068] Figure 3 is a schematic flow chart for determining the failure degree of the wire control braking system provided by the embodiment of the present application, as Figure 3 shown.

[0069] Suppose the second adjustment coefficient is , then the fourth acceleration is . If the target acceleration is greater than the fourth acceleration , it is determined that the failure degree of the wire control braking system is a mild failure. If the target acceleration is not greater than the fourth acceleration , it is determined that the failure degree of the wire control braking system is a severe failure.

[0070] By using a decimal, and this decimal is positive, to adjust the third acceleration, the acceleration for comparison can be further reduced, thereby further restricting the target acceleration and improving the accuracy of the judgment result. In addition, by distinguishing different failure degrees, the ECU can take corresponding processing measures subsequently, avoiding the problem that the risk of the mine car may increase due to immediately enabling a large braking force to brake the mine car in case of a mild failure.

[0071] The embodiment of the present application also considers that the third acceleration corresponding to the mine car in different load states should be different, so as to use the third acceleration corresponding to the load state for failure judgment, further improving the accuracy of the judgment result.

[0072] Specifically, determine the current load state of the autonomous driving mine car, where the current load state includes an empty load state or a non-empty load state; obtain the first adjustment coefficient corresponding to the current load state, wherein the first adjustment coefficient corresponding to the non-empty load state is less than the first adjustment coefficient corresponding to the empty load state; use the first adjustment coefficient corresponding to the current load state to adjust the reference acceleration to obtain the third acceleration.

[0073] The current load state of the autonomous mining truck can be determined according to the pressure sensed by the pressure sensor, or by other means. The embodiments of the present application do not limit this. For example, when the pressure sensed by the pressure sensor of the mining truck is not greater than the preset first pressure, the mining truck is in an unloaded state; when the pressure sensed by the pressure sensor of the mining truck is greater than the preset first pressure, the mining truck is in a non-unloaded state.

[0074] The non-unloaded state may include a heavy load state, a light load state, etc., but specific detailed classification can be made according to needs. For example, when the pressure sensed by the pressure sensor of the mining truck is less than the preset second pressure and greater than the preset first pressure, the mining truck is in a light load state; when the pressure sensed by the pressure sensor of the mining truck is not less than the preset second pressure, the mining truck is in a heavy load state. Among them, the first pressure is less than the second pressure.

[0075] It should be noted that the first adjustment coefficient corresponding to the non-unloaded state is less than the first adjustment coefficient corresponding to the unloaded state because the inertia of the mining truck in the non-unloaded state is large and the braking effect is slightly lower than that in the unloaded state. In addition, in the case of the non-unloaded state, too fast braking may cause accidents such as the mining truck tipping over.

[0076] For example, the first adjustment coefficient corresponding to the unloaded state can be , then the third acceleration is , the first adjustment coefficient corresponding to the non-unloaded state can be , then the third acceleration is .

[0077] Exemplarily, considering the applicability in different weather and different road sections, The value range of can be [0.7, 0.8), The value range of can be [0.8, 0.9), The value range of can be [0.6, 0.9].

[0078] In practical applications, the working environment of the mining truck is complex and changeable, and the vehicle load state has a significant impact on the braking performance. The traditional method fails to fully consider the impact of the load state on the braking failure judgment, resulting in the same judgment criteria under different vehicle load states, further reducing the accuracy of the judgment. The embodiments of the present application improve the accuracy of the judgment by distinguishing between the unloaded and non-unloaded states, and the thresholds for judging severe failure and mild failure are different under different states.

[0079] The embodiments of the present application also provide corresponding feedback processing schemes for different failure degrees. Specifically, if it is determined that the failure degree of the electronic brake system is mild failure, a speed reduction instruction is sent to the electronic brake system, and an alarm code is displayed; if the failure degree of the electronic brake system is severe failure, the autonomous mining truck is decelerated through the hydraulic retarder control, and an alarm code is displayed.

[0080] Traditional methods often adopt a one-size-fits-all approach when the braking fails, that is, immediately applying the maximum braking force to quickly stop the mine car, which actually further increases the safety hazards of the mine car. In contrast, this application adopts different processing strategies based on different failure degrees, that is, ensuring the safe operation of the vehicle in case of braking failure through an intelligent response mechanism.

[0081] Specifically, when the ECU determines that the vehicle has a mild failure, it will immediately feedback relevant information to the wire control braking system, requesting the vehicle to reduce the planned driving speed to ensure safe operation even when the braking performance partially decreases. When the ECU detects a severe failure, it will trigger the post-failure processing module and start the auxiliary braking system, gradually reducing the vehicle speed through the auxiliary braking method until the vehicle completely stops. In other words, after determining a severe failure, an auxiliary braking operation is taken, that is, triggering the hydraulic retarder switch, using the liquid damping to generate a retardation effect on the output shaft of the gearbox to achieve the effect of decelerating braking, and at the same time feedback an alarm code. This is because a severe failure means that the mine car does not have braking ability, so other braking methods need to be used to stop the mine car to ensure the safety of the mine car.

[0082] Figure 4 Another schematic diagram of the process for determining whether the wire control braking system fails provided by the embodiment of this application is as Figure 4 shown.

[0083] In the embodiment of this application, taking the heavy load in the non-empty load state as an example for illustration, the ECU can first determine the vehicle stage, that is, determine the current load state of the autonomous driving mine car. If the current load state is a heavy load, it can first determine whether the wire control braking system has a severe braking failure, that is, whether the failure degree of the wire control braking system is a severe failure. This is because for a mine car, if the wire control braking system has a severe failure, the situation is more urgent and more dangerous. To ensure the safety of the mine car, auxiliary braking needs to be carried out in a shorter time.

[0084] When determining whether the wire control braking system has a severe failure, the first adjustment parameter corresponding to the heavy load state can be obtained and the second adjustment parameter , and the reference acceleration is adjusted according to the first adjustment parameter to obtain the third acceleration . Since the absolute values of the accelerations are compared, when making the adjustment, the absolute value of the reference acceleration can also be directly adjusted. Then, the third acceleration can be . The following adjustment of the acceleration is also applicable to the adjustment of the absolute value of the acceleration, which will not be elaborated in the following embodiments of this application. The reference acceleration can also be adjusted according to the first adjustment parameter and the second adjustment parameter ​ Adjust to obtain the fourth acceleration .

[0085] When the target acceleration is less than the fourth acceleration , it is determined that the wire brake system has a severe failure, and auxiliary braking can be performed. When the target acceleration is not less than the fourth acceleration , the wire brake system may have a minor braking failure (mild failure) or may not have failed. Further judgment can be made based on the third acceleration .

[0086] Specifically, when the target acceleration is less than the third acceleration , it is determined that the wire brake system has a mild failure, and the planned speed can be reduced. The planned speed can be determined by the planning module according to the current road conditions, and the embodiments of the present application do not limit this. The current vehicle speed can also be reduced until it stops. When the target acceleration is not less than the third acceleration , the wire brake system has not failed, and the mining truck can drive normally

[0087] If the current load state is light load, the first adjustment parameter corresponding to the light load state and the second adjustment parameter can be obtained. According to the first adjustment parameter , the reference acceleration is adjusted to obtain the third acceleration . The reference acceleration can also be adjusted according to the first adjustment parameter and the second adjustment parameter to obtain the fourth acceleration .

[0088] When the target acceleration is less than the fourth acceleration , it is determined that the wire brake system has a severe failure, and auxiliary braking can be performed. When the target acceleration is not less than the fourth acceleration , the wire brake system may have a mild failure or may not have failed. Further judgment can be made based on the third acceleration .

[0089] Specifically, when the target acceleration is less than the third acceleration When it is determined that the electronic stability program (ESP) system is in a mild failure state, the planned speed can be reduced. The planned speed can be determined by the planning module according to the current road conditions, and this application embodiment does not limit this. The current vehicle speed can also be reduced until the vehicle stops. When the target acceleration is not less than the third acceleration the ESP system is not in failure, and the mining truck can travel normally.

[0090] Among them, the second adjustment parameter can also be called the severe braking failure coefficient , and the first adjustment parameter under heavy load can also be called the first braking failure warning threshold , and the first adjustment parameter under light load can also be called the second braking failure warning threshold .

[0091] It can be understood that in this application embodiment, a chassis response delay time compensation mechanism and a multi-parameter comprehensive analysis technology are adopted, which have significant beneficial effects compared with the traditional failure judgment method of the electronic stability program (ESP) system of mining trucks. First, the method of this application embodiment can timely and accurately judge whether the braking system of the mining truck fails, effectively solving the problem that the ESP system quickly fails due to the increase in working hours in the harsh working environment of driverless mining trucks, thus ensuring the safe operation of the mining truck under complex working conditions. Second, the method of this application embodiment overcomes the defects of the traditional method that relies on a single index and ignores the chassis response delay by introducing multi-parameter analysis and compensation of the chassis response delay time, calculates the actual braking acceleration of the vehicle from the moment when the chassis really starts to respond to braking, and significantly improves the accuracy and reliability of the braking system failure judgment. Finally, the method of this application embodiment realizes an intelligent response to the braking failure situation through a hierarchical processing strategy, distinguishing between empty and heavy load driving states: in the case of mild braking failure, the speed is reduced to the ESP system to ensure the safety of the vehicle when the braking performance partially decreases; in the case of severe braking failure, the auxiliary braking system is started by the post-failure processing module, and the speed is gradually reduced until the vehicle stops, maximizing the safety of the vehicle and the working environment.

[0092] Figure 5 FIG. Figure 5 shows the failure judgment module diagram of the electronic stability program (ESP) system of the autonomous driving mining truck provided by this application embodiment.

[0093] This module includes a chassis by-wire data acquisition module for acquiring the chassis speed, a positioning data acquisition module for acquiring the positioning speed, a calculation and failure module for determining various accelerations and judging whether the ESP system fails, and a post-failure processing module for determining corresponding processing strategies according to different failure degrees.

[0094] An embodiment of the present application provides a failure judgment device for a wire control braking system of an autonomous mining truck, as Figure 6 shown. The failure judgment device 60 of the wire control braking system of the autonomous mining truck may include: an emergency braking instruction issuing module 601, a first parameter acquisition module 602, a second parameter acquisition module 603, a target acceleration determination module 604, and a failure judgment module 605, where: The emergency braking instruction issuing module 601 is configured to issue an emergency braking instruction to the wire control braking system of the autonomous mining truck when a preset emergency braking condition is satisfied, and record a first moment when the emergency braking instruction is issued; The first parameter acquisition module 602 is configured to acquire a first chassis speed and a first positioning speed of the autonomous mining truck at a second moment, where the second moment is a moment after a preset delay duration starting from the first moment; The second parameter acquisition module 603 is configured to acquire a second chassis speed and a second positioning speed of the autonomous mining truck at a target moment, where the target moment includes a moment when the vehicle speed is first 0 after the emergency braking instruction is issued, or a moment after a preset delay duration after a cancellation instruction is issued, and the cancellation instruction is used to cancel the emergency braking instruction; The target acceleration determination module 604 is configured to determine a first acceleration of the autonomous mining truck from the second moment to the target moment according to the second chassis speed and the first chassis speed; determine a second acceleration of the autonomous mining truck from the second moment to the target moment according to the second positioning speed and the first positioning speed; and determine a target acceleration according to the first acceleration and the second acceleration; The failure judgment module 606 is configured to determine whether the wire control braking system fails according to the target acceleration and a preset reference acceleration.

[0095] Optionally, the target acceleration determination module 604 may be configured to acquire a first weight of the first acceleration and a second weight of the second acceleration; Perform weighted summation on the first acceleration and the second acceleration according to the first weight and the second weight to obtain a target acceleration.

[0096] Optionally, the failure judgment module 605 may be configured to adjust the reference acceleration by using a preset first adjustment coefficient to obtain a third acceleration, where the first adjustment coefficient is less than 1 and greater than 0; When the target acceleration is greater than or equal to the third acceleration, determine that the failure state of the wire control braking system is not failed; When the target acceleration is equal to or less than the third acceleration, determine that the failure state of the electronic brake system is a failure.

[0097] Optionally, the failure determination module 605 may be configured to adjust the third acceleration by using a preset second adjustment coefficient to obtain a fourth acceleration, where the second adjustment coefficient is less than 1 and greater than 0; When the target acceleration is greater than or equal to the fourth acceleration, determine that the failure degree of the electronic brake system is a minor failure; When the target acceleration is equal to or less than the fourth acceleration, determine that the failure degree of the electronic brake system is a severe failure.

[0098] Optionally, the failure determination module 605 may be configured to determine the current load state of the autonomous mining truck, where the current load state includes an unloaded state or a non-unloaded state; Obtain a first adjustment coefficient corresponding to the current load state, where the first adjustment coefficient corresponding to the non-unloaded state is less than the first adjustment coefficient corresponding to the unloaded state; Adjust the reference acceleration by using the first adjustment coefficient corresponding to the current load state to obtain the third acceleration.

[0099] Optionally, the device further includes: A failure handling module, configured to, if it is determined that the failure degree of the electronic brake system is a minor failure, send a speed reduction instruction to the electronic brake system and display an alarm code; If the failure degree of the electronic brake system is a severe failure, control the autonomous mining truck to decelerate through a hydraulic retarder and display an alarm code.

[0100] The device according to the embodiment of the present application can execute the method provided in the embodiment of the present application, and its implementation principle is similar, and it has corresponding technical effects. The actions performed by each module in the device according to the embodiments of the present application correspond to the steps in the method according to the embodiments of the present application. For a detailed function description of each module of the device, reference may specifically be made to the description in the corresponding method shown above, and details are not described herein again.

[0101] An electronic device is provided in an embodiment of the present application, including a memory, a processor, and a computer program stored on the memory, and the processor executes the computer program to implement the steps of the method provided in any optional embodiment of the present application.

[0102] In an optional embodiment, an electronic device is provided, as Figure 7 shown, Figure 7The illustrated electronic device 4000 includes: a processor 4001 and a memory 4003. Among them, the processor 4001 and the memory 4003 are connected, such as being connected through a bus 4002. Optionally, the electronic device 4000 may further include a transceiver 4004, and the transceiver 4004 can be used for data interaction between this electronic device and other electronic devices, such as data sending and / or data receiving, etc. It should be noted that in practical applications, the transceiver 4004 is not limited to one, and the structure of the electronic device 4000 does not constitute a limitation on the embodiments of the present application.

[0103] The processor 4001 can be a CPU (Central Processing Unit, central processor), a general-purpose processor, a DSP (Digital Signal Processor, data signal processor), an ASIC (Application Specific Integrated Circuit, application-specific integrated circuit), an FPGA (Field Programmable Gate Array, field programmable gate array), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute various exemplary logic blocks, modules, and circuits described in connection with the present disclosure. The processor 4001 can also be a combination that realizes computing functions, such as a combination including one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0104] The bus 4002 may include a path for transmitting information between the above components. The bus 4002 can be a PCI (Peripheral Component Interconnect, peripheral component interconnect standard) bus or an EISA (Extended Industry Standard Architecture, extended industry standard architecture) bus, etc. The bus 4002 can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 7 only a thick line is used to represent it in the figure, but it does not mean that there is only one bus or one type of bus.

[0105] The memory 4003 can be a ROM (Read Only Memory), or other types of static storage devices that can store static information and instructions, a RAM (Random Access Memory), or other types of dynamic storage devices that can store information and instructions. It can also be an EEPROM (Electrically Erasable Programmable Read Only Memory), a CD-ROM (Compact Disc Read Only Memory), or other optical disc storage, optical disc storage (including compact discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), magnetic disk storage media, other magnetic storage devices, or any other medium that can be used to carry or store computer programs and can be read by a computer, which is not limited herein.

[0106] The memory 4003 is used to store the computer program for implementing the embodiments of the present disclosure and is controlled by the processor 4001 for execution. The processor 4001 is used to execute the computer program stored in the memory 4003 to implement the steps shown in the foregoing method embodiments.

[0107] The embodiments of the present application provide a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps and corresponding contents of the foregoing method embodiments can be implemented.

[0108] The embodiments of the present application also provide a computer program product, including a computer program. When the computer program is executed by a processor, the steps and corresponding contents of the foregoing method embodiments can be implemented.

[0109] It should be understood that although the flowcharts in the embodiments of the present application indicate each operation step by arrows, the execution order of these steps is not limited to the order indicated by the arrows. Unless there is a clear description in this article, in some implementation scenarios of the embodiments of the present application, the implementation steps in each flowchart can be executed in other orders according to requirements. In addition, some or all of the steps in each flowchart may include multiple sub-steps or multiple stages based on the actual implementation scenario. Some or all of these sub-steps or stages can be executed at the same time, and each sub-step or stage of these sub-steps or stages can also be executed at different times respectively. In the scenario where the execution times are different, the execution order of these sub-steps or stages can be flexibly configured according to requirements, and the embodiments of the present application do not limit this.

[0110] The above are only alternative implementation manners of some implementation scenarios of the present disclosure. It should be noted that for those of ordinary skill in the art, without departing from the technical concept of the solution of the embodiments of the present application, adopting other similar implementation means based on the technical idea of the present disclosure also belongs to the protection scope of the embodiments of the present application.

Claims

1. A method for determining failure of a brake-by-wire system of an autonomous mining vehicle, characterized in that: include: When a preset emergency braking condition is met, an emergency braking command is issued to the wire control braking system of the autonomous driving mining vehicle, and the first moment of issuing the emergency braking command is recorded; Obtaining a first chassis speed and a first positioning speed of the autonomous mining vehicle at a second moment, where the second moment is a moment after a preset delay time period starting from the first moment; Obtaining a second chassis speed and a second positioning speed of the autonomous mining vehicle at a target time, wherein the target time includes a time when the vehicle speed is 0 for the first time after the emergency braking instruction is issued, or a time after a preset delay time has elapsed after a cancellation instruction is issued, wherein the cancellation instruction is used to cancel the emergency braking instruction; determining a first acceleration of the autonomous mining vehicle from the second moment to the target moment according to the second chassis speed and the first chassis speed; determining a second acceleration of the autonomous mining vehicle from the second moment to the target moment according to the second positioning speed and the first positioning speed; determining a target acceleration according to the first acceleration and the second acceleration; Whether the brake-by-wire system fails is determined according to the target acceleration and a preset reference acceleration.

2. The method according to claim 1, characterized in that The determining the target acceleration according to the first acceleration and the second acceleration includes: Obtaining a first weight of the first acceleration and a second weight of the second acceleration; The first acceleration and the second acceleration are weightedly summed according to the first weight and the second weight to obtain a target acceleration.

3. The method according to claim 1 or 2, characterized in that: The determining whether the brake-by-wire system fails according to the target acceleration and the preset reference acceleration includes: The reference acceleration is adjusted by using a preset first adjustment coefficient to obtain a third acceleration, wherein the first adjustment coefficient is less than 1 and greater than 0; When the target acceleration is greater than or equal to the third acceleration, determining that the failure state of the brake-by-wire system is not failed; When the target acceleration is equal to or less than the third acceleration, it is determined that the failure state of the brake-by-wire system is a failure.

4. The method according to claim 3, characterized in that When the target acceleration is equal to or less than the third acceleration, determining that the failure state of the brake-by-wire system is failure includes: The third acceleration is adjusted by using a preset second adjustment coefficient to obtain a fourth acceleration, wherein the second adjustment coefficient is less than 1 and greater than 0; When the target acceleration is greater than or equal to the fourth acceleration, determining that the failure degree of the brake-by-wire system is a slight failure; When the target acceleration is equal to or less than the fourth acceleration, it is determined that the failure degree of the brake-by-wire system is a severe failure.

5. The method according to claim 3 or 4, characterized in that: The step of adjusting the reference acceleration by using a preset first adjustment coefficient to obtain a third acceleration includes: Determining a current load state of the autonomous mining vehicle, wherein the current load state includes an empty state or a non-empty state; Acquire a first adjustment coefficient corresponding to the current load state, wherein the first adjustment coefficient corresponding to the non-no-load state is smaller than the first adjustment coefficient corresponding to the no-load state; The reference acceleration is adjusted using a first adjustment coefficient corresponding to the current load state to obtain the third acceleration.

6. The method according to claim 4, characterized in that The method further comprises: If it is determined that the failure degree of the brake-by-wire system is a slight failure, sending a speed reduction instruction to the brake-by-wire system and displaying a warning code; If the failure degree of the brake-by-wire system is severe, the automatic driving mine car is decelerated by hydraulic retarder control and a warning code is displayed.

7. A failure judgment device for a wire control brake system of an automatic driving mine car, characterized in that: include: An emergency braking instruction issuing module is used to issue an emergency braking instruction to the wire control braking system of the autonomous driving mining vehicle when a preset emergency braking condition is met, and record the first moment of issuing the emergency braking instruction; A first parameter acquisition module is used to acquire a first chassis speed and a first positioning speed of the autonomous mining vehicle at a second moment, where the second moment is a moment after a preset delay time period starting from the first moment; A second parameter acquisition module is used to acquire a second chassis speed and a second positioning speed of the autonomous mining vehicle at a target time, wherein the target time includes a time when the vehicle speed is 0 for the first time after the emergency braking instruction is issued, or a time after the preset delay time has elapsed after a cancellation instruction is issued, and the cancellation instruction is used to cancel the emergency braking instruction; a target acceleration determination module, configured to determine a first acceleration of the autonomous mine car from the second moment to the target moment according to the second chassis speed and the first chassis speed; determine a second acceleration of the autonomous mine car from the second moment to the target moment according to the second positioning speed and the first positioning speed; and determine a target acceleration according to the first acceleration and the second acceleration; The failure judgment module is used to determine whether the brake-by-wire system fails according to the target acceleration and a preset reference acceleration.

8. An electronic device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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