Filtering processing method and apparatus for engine rotation speed signal, device, and medium

Abstract

The present application relates to the technical field of processing of engine rotation speed signals, and discloses a filtering processing method and apparatus for an engine rotation speed signal, a device, and a medium. The method comprises: acquiring a rotation speed signal, and calculating a cycle of the rotation speed signal, an average duration of a high level in one cycle, and a cycle change rate; determining whether a processing position corresponding to the rotation speed signal is a normal position of a gear or a tooth-missing position of the gear; and for different processing positions, using different filtering policies to filter out interference signals. The present application is used to solve the problem in the existing technology of a poor effect in filtering out an interference signal from an engine rotation speed signal, thereby achieving effective filtering of an interference signal out from an engine rotation speed signal.

Description

Methods, devices, equipment, and media for filtering engine speed signals Technical Field

[0001] This application relates to the field of engine speed signal processing technology, and in particular to a method, apparatus, device and medium for filtering engine speed signals. Background Technology

[0002] The engine speed signal is provided by the crankshaft position sensor. The crankshaft position sensor is a crucial component of the engine management system, specifically used to monitor engine speed and convert this information into an electrical signal. The crankshaft position sensor operates based on the principle of magneto-electric induction. When the crankshaft rotates, the magnet inside the sensor rotates as well, generating a changing magnetic field. This change is sensed by the coil inside the sensor, thus producing an electrical signal. The frequency of this electrical signal is directly proportional to the engine speed; that is, the faster the engine speed, the higher the frequency of the generated electrical signal.

[0003] Engine speed signals are generated based on the principle of magnetoelectric induction. The signal amplitude varies with the engine speed; a higher signal amplitude also results in higher interference amplitude, making the signal prone to multi-tooth or missing-tooth anomalies. Furthermore, current technologies primarily address engine speed signal interference through hardware circuits, but these hardware circuits have limited capabilities. When the interference signal strength is high, the hardware circuits cannot effectively filter out the interference signal. Technical issues

[0004] The existing technology has the problem of poor filtering effect of interference signals in engine speed signals. Technical solutions

[0005] In response to the aforementioned problems and technical requirements, the applicant has proposed a filtering method, device, equipment, and medium for engine speed signals to solve the problem of poor interference signal filtering in existing technologies and to achieve effective filtering of interference signals in engine speed signals.

[0006] This application provides a method for filtering engine speed signals, the method comprising:

[0007] Acquire the rotational speed signal and calculate the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period;

[0008] Determine whether the processing position corresponding to the speed signal is the normal position of the gear or the position where the gear has a missing tooth;

[0009] If the processing position is determined to be the normal position of the gear, the following interference signal filtering process is performed: the actual duration of each high level within the period is obtained; the actual duration and the average duration are input into a preset first determination formula to determine whether the correspondence between the actual duration and the average duration is valid, and interference signals are filtered out based on the determination result;

[0010] If the processing position is determined to be the missing tooth position of the gear, the interference signal filtering process is executed, and after the interference signal filtering process is executed, the number of square waves between the previous missing tooth position and the next missing tooth position is calculated; if the number of square waves is determined to be greater than a preset value, the interference signal is filtered out based on the periodic change rate.

[0011] The periodic change rate includes the change rate of any two adjacent square waves between the previous tooth-missing position and the next tooth-missing position.

[0012] According to an embodiment of the filtering method for engine speed signals in this application, the first determination formula includes: t_p < αt;

[0013] Where t_p represents the actual duration, α is a constant less than 1 and greater than 0, and t represents the average duration;

[0014] The filtering of interference signals based on the judgment results includes:

[0015] If it is determined that the determination result is valid in characterizing the correspondence between the actual duration and the average duration, the signal corresponding to the current high level is identified as an interference signal and deleted.

[0016] If the determination result is determined to be invalid in characterizing the correspondence between the actual duration and the average duration, interference signals are filtered out based on the periodic change rate.

[0017] According to an embodiment of the filtering method for engine speed signals, the method filters out interference signals based on the periodic change rate, including:

[0018] If the periodic change rate is determined to be greater than the preset change rate, the square wave corresponding to the current period is determined to be an interference waveform and is deleted.

[0019] According to an embodiment of the filtering method for engine speed signals, the method filters out interference signals based on the periodic change rate, including:

[0020] Input the current period, the previous period, and the period change rate into the preset second judgment formula, and if the second judgment formula is found to be true after input, determine that the square wave corresponding to the current period is an interference waveform and perform a deletion operation.

[0021] The second determination formula includes: T_1>T_2+βv;

[0022] Where T_1 represents the current period, T_2 represents the previous period, β represents a constant greater than 1, and v represents the periodic rate of change.

[0023] According to an embodiment of the filtering method for engine speed signals, when it is determined that the number of square waves is greater than a preset value, interference signals are filtered out based on the periodic change rate, including:

[0024] Calculate the target difference between the number of square waves and the preset value;

[0025] Based on a preset mapping relationship between the difference and the deletion strategy, a target deletion strategy corresponding to the target difference is obtained, and interference signals are filtered out based on the target deletion strategy, wherein the deletion strategy is obtained based on the periodic rate of change.

[0026] According to an embodiment of the filtering method for engine speed signals, the method filters out interference signals based on the target deletion strategy, including:

[0027] When the difference is equal to 1, the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate is determined from the periodic change rate, and the determined square wave is deleted.

[0028] If the difference is greater than 1, the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate is determined from the periodic change rate, and the determined square wave is deleted. The periodic change rate is recalculated until the number of deletion operations reaches the difference.

[0029] According to an embodiment of the filtering method for engine speed signals, the method acquires the speed signal and calculates the period of the speed signal, the average duration of the high level within one period, and the rate of change of the period, including:

[0030] Determine the rotational speed value corresponding to the rotational speed signal, and calculate the reciprocal of the rotational speed value to obtain the period of the rotational speed signal;

[0031] For each high level, the start state and end state of the high level are captured based on a preset timer, and the timer starts from the start state of the high level and stops from the end state of the high level to obtain the actual duration of the high level; the sum of multiple high levels is calculated, and the number of high levels is divided by the summation result to obtain the average duration;

[0032] The periodicity variation rate is obtained by calculating the rate of change between the actual duration of the high level of the square wave at the previous timestamp and the actual duration of the high level of the square wave at the next timestamp of any adjacent square waves.

[0033] This application embodiment also provides a filtering processing device for engine speed signals, including:

[0034] The calculation module is used to acquire the rotational speed signal and calculate the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period.

[0035] The determination module is used to determine whether the processing position corresponding to the speed signal is the normal position of the gear or the position where the gear has a missing tooth.

[0036] The first filtering module is used to perform the following interference signal filtering process when it is determined that the processing position is the normal position of the gear: obtain the actual duration of each high level in the period; input the actual duration and the average duration into a preset first judgment formula to determine whether the correspondence between the actual duration and the average duration is valid, and filter out the interference signal based on the judgment result;

[0037] The second filtering module is used to perform the interference signal filtering process when the processing position is determined to be the missing tooth position of the gear, and after performing the interference signal filtering process, to calculate the number of square waves between the previous missing tooth position and the next missing tooth position; and to filter the interference signal based on the periodic change rate when the number of square waves is determined to be greater than a preset value.

[0038] The periodic change rate includes the change rate of any two adjacent square waves between the previous tooth-missing position and the next tooth-missing position.

[0039] This application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the filtering processing method for engine speed signals as described in any of the preceding claims.

[0040] This application also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the filtering processing method for the engine speed signal as described in any of the preceding claims. Beneficial effects

[0041] The engine speed signal filtering method, apparatus, device, and medium provided in this application embodiment acquire the speed signal and calculate its period, the average duration of the high level within one period, and the period change rate; determine whether the processing position corresponding to the speed signal is a normal gear position or a gear tooth-missing position; if the processing position is determined to be a normal gear position, perform the following interference signal filtering process: acquire the actual duration of each high level within the period; input the actual duration and average duration into a preset first determination formula to determine whether the correspondence between the actual duration and average duration is valid, and filter the interference signal based on the determination result; if the processing position is determined to be a gear tooth-missing position, execute the interference signal filtering process. The process involves filtering out interference signals, and after performing the interference signal filtering process, calculating the number of square waves between the previous gear tooth-missing position and the next gear tooth-missing position. If the number of square waves is greater than a preset value, interference signals are filtered out based on the periodic change rate. This application filters out interference signals by calculating the characteristics of the speed signal (period, average duration, and periodic change rate), identifying the normal gear position and the gear tooth-missing position, and using the calculated characteristics of the speed signal to apply different filtering strategies. This method does not require any additional hardware circuitry and is unaffected by the engine speed, effectively filtering out interference signals in the engine speed signal and solving the problem of poor interference signal filtering in the engine speed signal in the prior art. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 is a waveform diagram of the rotation speed signal after processing without interference signals according to an embodiment of this application;

[0044] Figure 2 is a waveform diagram of the rotation speed signal after processing with interference signals according to an embodiment of this application;

[0045] Figure 3 is a flowchart illustrating the filtering method for engine speed signals provided in an embodiment of this application;

[0046] Figure 4 is a schematic diagram of the structure of the engine speed signal filtering device provided in the embodiment of this application;

[0047] Figure 5 is a schematic diagram of the structure of the electronic device provided in an embodiment of this application. Embodiments of the present invention

[0048] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0049] To further clarify the implications of this application regarding signal interference:

[0050] Specifically, the crankshaft position sensor is mounted directly opposite the flywheel teeth and fixed to the flywheel housing. When the flywheel rotates, the gap between the head of the crankshaft position sensor and the gear ring changes. As the gap changes, the magnetic flux of the coil inside the crankshaft position sensor also changes, thereby generating a sine wave-like signal. One rotation of a tooth generates one cycle of the sine wave.

[0051] The processed waveform is shown in Figure 1.

[0052] Furthermore, the crankshaft gear signal is 60-2, which has two missing teeth. Therefore, the current phase of the engine can be determined by identifying the location of the missing teeth.

[0053] Figure 2 shows the situation where the engine speed signal is interfered with.

[0054] There are two types of signal interference: one is abnormal interference signal generated at the normal position of the gear, which is mainly manifested as an increase of one or more square waves; the other is abnormal interference signal generated at the missing tooth of the gear, which is also mainly manifested as an increase of one or more square waves.

[0055] This application provides a filtering method for engine speed signals, which can generate corresponding filtering strategies for different types of interference to solve signal interference problems. This method can be applied to smart terminals and servers. Other descriptions in this application are illustrative and not intended to limit the scope of protection of this application, and will not be described in detail thereafter. The specific implementation of this method is shown in Figure 3:

[0056] Step 301: Acquire the rotational speed signal and calculate the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period.

[0057] Step 302: Determine whether the processing position corresponding to the speed signal is the normal position of the gear or the position where the gear is missing a tooth.

[0058] Step 303: If the processing position is determined to be the normal position of the gear, the following interference signal filtering process is performed: the actual duration of each high level within the cycle is obtained; the actual duration and average duration are input into the preset first judgment formula to determine whether the correspondence between the actual duration and the average duration is valid, and the interference signal is filtered out based on the judgment result.

[0059] Step 304: If the processing position is determined to be a missing tooth position of a gear, an interference signal filtering process is performed. After the interference signal filtering process is performed, the number of square waves between the previous missing tooth position and the next missing tooth position of the gear is calculated. If the number of square waves is determined to be greater than a preset value, the interference signal is filtered out based on the periodic change rate.

[0060] The periodic change rate includes the change rate between any two adjacent square waves from the previous tooth-missing position to the next tooth-missing position. Specifically, it is obtained by the change rate of the actual duration of the high level of the square wave at the previous timestamp and the actual duration of the high level of the square wave at the next timestamp of any adjacent square waves.

[0061] The processing position is the position that changes in real time as the filtering process is executed.

[0062] The engine speed signal filtering method provided in this application involves acquiring the speed signal and calculating its period, the average duration of the high level within one period, and the period change rate. It then determines whether the processing position corresponding to the speed signal is a normal gear position or a gear tooth-missing position. If the processing position is determined to be a normal gear position, the following interference signal filtering process is performed: acquiring the actual duration of each high level within the period; inputting the actual duration and average duration into a preset first determination formula to determine whether the correspondence between the actual duration and average duration is valid, and filtering interference signals based on the determination result; and performing the interference signal filtering process if the processing position is determined to be a gear tooth-missing position. After performing the interference signal filtering process, the number of square waves between the previous gear tooth-missing position and the next gear tooth-missing position is calculated. If the number of square waves is greater than a preset value, the interference signal is filtered based on the periodic change rate. This application filters the interference signal by calculating the characteristics of the speed signal (period, average duration, and periodic change rate) and by identifying the normal gear position and the gear tooth-missing position. It uses the calculated characteristics of the speed signal to apply different filtering strategies to filter the interference signal. No additional hardware circuitry is required, and it is not affected by the engine speed. It can effectively filter the interference signal in the engine speed signal, solving the problem of poor interference signal filtering effect in the engine speed signal in the prior art.

[0063] Furthermore, the filtering strategy of this application is based on the specified engine speed, which is more accurate. Since the engine speed is calculated by the crankshaft gear rotation, the crankshaft rotation rate will not jump, but will only change at a constant speed, and will not interfere with the signal.

[0064] Specifically, the acquired rotational speed signal is the processed rotational speed signal.

[0065] First, an initial rotational speed signal is obtained. This initial rotational speed signal is the raw signal input from the sensor. The rotational speed processing hardware circuit converts the analog signal into a digital signal. Then, the digital signal is sent to the microcontroller. The microcontroller receives the digital signal (the processed rotational speed signal) and calculates the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period.

[0066] In one specific embodiment, the acquisition of the rotational speed signal and the calculation of the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period include the following specific implementation:

[0067] Determine the rotational speed value corresponding to the rotational speed signal, and calculate the reciprocal of the rotational speed value to obtain the period of the rotational speed signal; for each high level, capture the high level start state and high level end state based on a preset timer, and start timing from the high level start state until the high level end state to stop timing, to obtain the actual duration of the high level; sum the multiple high levels, and use the summation result to divide the number of high levels to obtain the average duration; calculate the rate of change of the duration of the high level of any adjacent square wave between the actual duration of the high level of the square wave at the previous timestamp and the actual duration of the high level of the square wave at the next timestamp, to obtain the period change rate.

[0068] In one specific embodiment, the first determination formula is shown in formula (1):

[0069] t_p<αt……………………………………………………..(1)

[0070] Where t_p represents the actual duration, α is a constant less than 1 and greater than 0, and t represents the average duration.

[0071] If the determination result is used to characterize the correspondence between the actual duration and the average duration, the signal corresponding to the current high level is identified as an interference signal and deleted; if the determination result is used to characterize the correspondence between the actual duration and the average duration, the interference signal is filtered out based on the periodic change rate.

[0072] For example, if α equals 0.2, then the first determination formula is t_p<0.2*t.

[0073] After inputting the actual duration and average duration into the first determination formula, if the first determination formula is valid, the current square wave is determined to be an interference waveform and is deleted.

[0074] In one specific embodiment, the specific implementation of filtering interference signals based on the periodic rate of change includes:

[0075] If the periodic change rate is determined to be greater than the preset change rate, the square wave corresponding to the current period is identified as an interference waveform and deleted.

[0076] Specifically, the signal corresponding to the high level of the square wave in the current cycle is identified as an interference signal and deleted.

[0077] In one specific embodiment, the specific implementation of filtering interference signals based on the periodic rate of change includes:

[0078] Input the current period, the previous period, and the rate of change of the period into the second determination formula. If the second determination formula is valid after input, determine that the square wave corresponding to the current period is an interference waveform and perform a deletion operation.

[0079] The second determination formula is shown in formula (2):

[0080] T_1>T_2+βv………………………………………….(2)

[0081] Where T_1 represents the current period, T_2 represents the previous period, β represents a constant greater than 1, and v represents the periodic rate of change.

[0082] The specific input parameters are the actual duration of the high level of the square wave in the current cycle, the actual duration of the high level of the square wave in the previous cycle, and the calculated rate of change of the cycle.

[0083] Specifically, if the second determination formula is true, the current square wave is determined to be an interference waveform, that is, the signal corresponding to the current square wave is an interference signal, and it is deleted.

[0084] In one specific embodiment, when the number of square waves is determined to be greater than a preset value, the specific implementation of filtering interference signals based on the periodic change rate includes:

[0085] Calculate the target difference between the number of square waves and the preset value; based on the preset mapping relationship between the difference and the deletion strategy, obtain the target deletion strategy corresponding to the target difference, and filter out the interference signal based on the target deletion strategy.

[0086] The deletion strategy is derived based on the periodic rate of change.

[0087] In one specific embodiment, the specific implementation of filtering interference signals based on the target deletion strategy includes:

[0088] If the difference is equal to 1, determine the square wave with the larger timestamp from the two square waves corresponding to the maximum periodic change rate from the periodic change rate, and delete the determined square wave; if the difference is greater than 1, determine the square wave with the larger timestamp from the two square waves corresponding to the maximum periodic change rate from the periodic change rate, and delete the determined square wave, and recalculate the periodic change rate until the number of deletion operations reaches the difference.

[0089] Specifically, the difference between the number of square waves and the preset value is calculated; if the difference is equal to 1, the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate is determined from the periodic change rate, and the determined square wave is deleted; if the difference is greater than 1, the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate is determined from the periodic change rate, and the determined square wave is deleted, and the periodic change rate is recalculated until the number of deletion operations reaches the difference.

[0090] Specifically, the crankshaft gear signal is 60-2, and the actual acquired waveform is 58. The counting is performed from the previous missing tooth to the next missing tooth. If the number of square waves counted is greater than 58, it indicates the presence of interference signals, requiring interference filtering.

[0091] If the difference is greater than 1, multiple iterative calculations and deletion operations are required. Specifically, the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate is determined from the periodic change rate, and the determined square wave is deleted. Based on the remaining square waves, the periodic change rate is recalculated, and the steps of determining the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate and deleting the determined square wave are repeated until the number of deletion operations reaches the difference.

[0092] This application solves the problem of numerous and significant interference signals in engine speed signals by identifying the normal and missing tooth positions of gears and utilizing the characteristics of the calculated speed signal to apply different filtering strategies. Furthermore, it requires no additional hardware circuitry and is unaffected by engine speed, effectively filtering out interference signals from engine speed signals. This overcomes the problem of poor interference signal filtering in existing technologies, reducing costs and improving user experience.

[0093] This application embodiment also provides a filtering processing device for engine speed signals. The specific implementation of this device can be found in the description of the filtering processing method for engine speed signals; details that are repeated will not be repeated. As shown in Figure 4, the device includes:

[0094] The calculation module 401 is used to acquire the rotational speed signal and calculate the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period.

[0095] The determination module 402 is used to determine whether the processing position corresponding to the speed signal is the normal position of the gear or the position where the gear has a missing tooth.

[0096] The first filtering module 403 is used to perform the following interference signal filtering process when the processing position is determined to be the normal position of the gear: obtain the actual duration of each high level within the period; input the actual duration and average duration into a preset first judgment formula to determine whether the correspondence between the actual duration and the average duration is valid, and filter out the interference signal based on the judgment result;

[0097] The second filtering module 404 is used to perform an interference signal filtering process when the processing position is determined to be a missing tooth position of a gear, and after performing the interference signal filtering process, to calculate the number of square waves between the previous missing tooth position and the next missing tooth position of the gear; and to filter out the interference signal based on the periodic change rate when the number of square waves is determined to be greater than a preset value.

[0098] The periodic rate of change includes the rate of change of any two adjacent square waves between the previous tooth-missing position and the next tooth-missing position.

[0099] In one specific embodiment, the first determination formula includes: t_p < αt.

[0100] Where t_p represents the actual duration, α is a constant less than 1 and greater than 0, and t represents the average duration. The first filtering module 403 is used to determine the signal corresponding to the current high level as an interference signal and delete it when the determination result indicating the correspondence between the actual duration and the average duration is valid; when the determination result indicating the correspondence between the actual duration and the average duration is invalid, it filters out the interference signal based on the periodic change rate.

[0101] In one specific embodiment, the second filtering module 404 is used to determine that the square wave corresponding to the current period is an interference waveform and perform a deletion operation when the period change rate is determined to be greater than a preset change rate.

[0102] In one specific embodiment, the second filtering module 404 is used to input the current period, the previous period and the period change rate into a preset second determination formula, and if the second determination formula after input is determined to be true, determine that the square wave corresponding to the current period is an interference waveform and perform a deletion operation.

[0103] The second determination formula includes: T_1>T_2+βv.

[0104] Where T_1 represents the current period, T_2 represents the previous period, β represents a constant greater than 1, and v represents the periodic rate of change.

[0105] In one specific embodiment, the second filtering module 404 is used to calculate the target difference between the number of square waves and a preset value; based on the preset mapping relationship between the difference and the deletion strategy, obtain the target deletion strategy corresponding to the target difference, and filter out the interference signal based on the target deletion strategy.

[0106] The deletion strategy is derived based on the periodic rate of change.

[0107] In one specific embodiment, the second filtering module 404 is used to determine the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate from the periodic change rate when the difference is equal to 1, and to delete the determined square wave; when the difference is greater than 1, determine the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate from the periodic change rate, and to delete the determined square wave, and recalculate the periodic change rate until the number of deletion operations reaches the difference.

[0108] In one specific embodiment, the calculation module 401 is used to determine the rotational speed value corresponding to the rotational speed signal, calculate the reciprocal of the rotational speed value to obtain the period of the rotational speed signal; for each high level, the high level start state and high level end state are captured based on a preset timer, and the timing starts from the high level start state and stops from the high level end state to obtain the actual duration of the high level; the sum of multiple high levels is calculated, and the number of high levels is divided by the summation result to obtain the average duration; the rate of change of the duration of the high level of any adjacent square wave at the previous timestamp and the actual duration of the high level of the square wave at the next timestamp is calculated to obtain the period change rate.

[0109] Figure 5 illustrates a schematic diagram of the physical structure of an electronic device. As shown in Figure 5, the electronic device may include: a processor 501, a communication interface 502, a memory 503, and a communication bus 504. The processor 501, communication interface 502, and memory 503 communicate with each other via the communication bus 504. The processor 501 can call logical instructions in the memory 503 to execute a filtering method for the engine speed signal.

[0110] Furthermore, the logical instructions in the aforementioned memory 503 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0111] On the other hand, the present invention also provides a computer program product, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, and when the program instructions are executed by a computer, the computer is able to execute the filtering processing method for engine speed signal provided by the above methods.

[0112] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the filtering processing method for the engine speed signal provided in the above embodiments.

[0113] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0114] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0115] Finally, it should be noted that the above descriptions are merely preferred embodiments of this application, and this application is not limited to the above embodiments. It is understood that other improvements and variations directly derived or conceived by those skilled in the art without departing from the spirit and concept of this application should be considered to be included within the protection scope of this application.

Claims

1. A method of filtering an engine speed signal, characterized by, The method includes: Acquire the rotational speed signal and calculate the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period; Determine whether the processing position corresponding to the speed signal is the normal position of the gear or the position where the gear has a missing tooth; If the processing position is determined to be the normal position of the gear, the following interference signal filtering process is performed: the actual duration of each high level within the period is obtained; the actual duration and the average duration are input into a preset first determination formula to determine whether the correspondence between the actual duration and the average duration is valid, and interference signals are filtered out based on the determination result; If the processing position is determined to be the missing tooth position of the gear, the interference signal filtering process is executed, and after the interference signal filtering process is executed, the number of square waves between the previous missing tooth position and the next missing tooth position is calculated; if the number of square waves is determined to be greater than a preset value, the interference signal is filtered out based on the periodic change rate. The periodic change rate includes the change rate of any two adjacent square waves between the previous tooth-missing position and the next tooth-missing position.

2. The engine speed signal filtering method according to claim 1, characterized by, The first determination formula includes: t_p < αt; Where t_p represents the actual duration, α is a constant less than 1 and greater than 0, and t represents the average duration; The filtering of interference signals based on the judgment results includes: If it is determined that the determination result is valid in characterizing the correspondence between the actual duration and the average duration, the signal corresponding to the current high level is identified as an interference signal and deleted. If the determination result is determined to be invalid in characterizing the correspondence between the actual duration and the average duration, interference signals are filtered out based on the periodic change rate.

3. The filtering method for engine speed signals according to claim 1 or 2, characterized in that, Filtering out interference signals based on the periodic rate of change includes: If the periodic change rate is determined to be greater than the preset change rate, the square wave corresponding to the current period is determined to be an interference waveform and is deleted.

4. The filtering method for engine speed signals according to claim 1 or 2, characterized in that, Filtering out interference signals based on the periodic rate of change includes: Input the current period, the previous period, and the period change rate into the preset second judgment formula, and if the second judgment formula is found to be true after input, determine that the square wave corresponding to the current period is an interference waveform and perform a deletion operation. The second determination formula includes: T_1>T_2+βv; Where T_1 represents the current period, T_2 represents the previous period, β represents a constant greater than 1, and v represents the periodic rate of change.

5. The filtering method for engine speed signals according to claim 1 or 2, characterized in that, If the number of square waves is determined to be greater than a preset value, interference signals are filtered out based on the periodicity rate of change, including: Calculate the target difference between the number of square waves and the preset value; Based on a preset mapping relationship between the difference and the deletion strategy, a target deletion strategy corresponding to the target difference is obtained, and interference signals are filtered out based on the target deletion strategy, wherein the deletion strategy is obtained based on the periodic rate of change.

6. The filtering method for engine speed signals according to claim 5, characterized in that, Filtering out interference signals based on the target deletion strategy includes: When the difference is equal to 1, the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate is determined from the periodic change rate, and the determined square wave is deleted. If the difference is greater than 1, the square wave with the larger timestamp among the two square waves corresponding to the maximum periodic change rate is determined from the periodic change rate, and the determined square wave is deleted. The periodic change rate is recalculated until the number of deletion operations reaches the difference.

7. The filtering method for engine speed signals according to claim 1 or 2, characterized in that, Acquire the rotational speed signal and calculate the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period, including: Determine the rotational speed value corresponding to the rotational speed signal, and calculate the reciprocal of the rotational speed value to obtain the period of the rotational speed signal; For each high level, the start state and end state of the high level are captured based on a preset timer, and the timer starts from the start state of the high level and stops from the end state of the high level to obtain the actual duration of the high level; the sum of multiple high levels is calculated, and the number of high levels is divided by the summation result to obtain the average duration; The periodicity variation rate is obtained by calculating the rate of change between the actual duration of the high level of the square wave at the previous timestamp and the actual duration of the high level of the square wave at the next timestamp of any adjacent square waves.

8. A filtering and processing device for engine speed signals, characterized in that, The device includes: The calculation module is used to acquire the rotational speed signal and calculate the period of the rotational speed signal, the average duration of the high level within one period, and the rate of change of the period. The determination module is used to determine whether the processing position corresponding to the speed signal is the normal position of the gear or the position where the gear has a missing tooth. The first filtering module is used to perform the following interference signal filtering process when it is determined that the processing position is the normal position of the gear: obtain the actual duration of each high level in the period; input the actual duration and the average duration into a preset first judgment formula to determine whether the correspondence between the actual duration and the average duration is valid, and filter out the interference signal based on the judgment result; The second filtering module is used to perform the interference signal filtering process when the processing position is determined to be the missing tooth position of the gear, and after performing the interference signal filtering process, to calculate the number of square waves between the previous missing tooth position and the next missing tooth position; and to filter the interference signal based on the periodic change rate when the number of square waves is determined to be greater than a preset value. The periodic change rate includes the change rate of any two adjacent square waves between the previous tooth-missing position and the next tooth-missing position.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the filtering processing method for the engine speed signal as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the steps of the filtering processing method for the engine speed signal as described in any one of claims 1 to 7.

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