Vehicle speed detection method, electronic equipment and computer readable storage medium

Abstract

The invention discloses a vehicle speed detection method, electronic equipment and a computer readable storage medium, and the method comprises the steps: determining the wheel rotation speed of a tire through employing at least one of tooth spacing time, a tooth spacing time sampling signal, a tooth number in a time interval, and a tooth number sampling signal in the time interval, and can improve the measurement precision of the wheel rotation speed; the vehicle speed is obtained by carrying out filtering and arbitration calculation on the tire rotating speed and the tire effective rolling radius, the influence of errors and abnormal data can be eliminated, the method is suitable for complex working conditions such as roll turning, and then the calculation accuracy of the vehicle speed is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electric motorcycle control, and in particular to a vehicle speed detection method, an electronic device and a computer-readable storage medium. Background Art

[0002] Motorcycles are two-wheeled vehicles that are not statically stable. Unlike car tires, motorcycle tire crowns are designed in an arc shape, which requires the use of the area where the tire surface contacts the ground when the tire is tilted to generate a difference in the inner and outer rolling radii, thereby generating a lateral slip angle similar to a tapered roller, allowing the motorcycle to turn.

[0003] At present, electric motorcycles are equipped with front and rear wheel speed sensors and 48-hole signal gear rings for the front and rear wheels. Electric motorcycles can read the square wave signals of the front and rear wheel speed sensors through the Anti-lock Braking System (ABS) controller or the Vehicle Control Unit (VCU) to calculate the front and rear wheel speeds. Compared with gasoline motorcycles, which need to use the preset tire rolling radius fixed parameters to calculate the front and rear wheel speeds, since electric motorcycles have rear motor speeds, they can use the transmission ratio to convert to the rear wheel speed and determine the speed of the entire electric motorcycle.

[0004] However, when an electric motorcycle turns, the actual tire rolling radius becomes smaller due to the roll angle, and the wheel speed increases. However, the tire rolling radius stored in the motorcycle instrument and other controllers is a fixed value, which causes the vehicle instrument speed and the controller to calculate the speed to be distorted and appear too large. Summary of the invention

[0005] The present application provides a vehicle speed detection method, an electronic device, and a computer-readable storage medium, which can improve the detection accuracy of the vehicle speed of an electric motorcycle.

[0006] A technical solution adopted in the present application is: to provide a vehicle speed detection method, the vehicle speed detection method comprising: obtaining the effective rolling radius of the vehicle tire; reading the wheel speed square wave signal of the gear ring hardware on the vehicle tire from the wheel speed sensor; processing the wheel speed square wave signal to obtain corresponding wheel speed information; wherein the wheel speed information includes at least one of the tooth spacing time, the tooth spacing time sampling signal, the number of teeth within the time interval and the number of teeth within the time interval sampling signal; determining the tire wheel speed based on the wheel speed information; filtering and arbitrating the tire wheel speed and the tire effective rolling radius to obtain the vehicle speed.

[0007] In some embodiments, the tire wheel speed is determined based on the wheel speed information, including: calculating the wheel speed using the tooth spacing time to obtain the first wheel speed, and calculating the wheel speed using the number of teeth within the time interval to obtain the second wheel speed; performing a reliability check on the tooth spacing time sampling signal to obtain a first weight corresponding to the first wheel speed, and performing a reliability check on the number of teeth sampling signal within the time interval to obtain a second weight corresponding to the second wheel speed; based on the size of the first weight and the second weight, the first wheel speed and the second wheel speed, switching to the corresponding calculation state to determine the tire wheel speed.

[0008] In some embodiments, the calculation state includes a tooth number calculation state within a time interval and a tooth spacing time calculation state; based on the size of the first weight and the second weight, the first wheel speed and the second wheel speed, switching to the corresponding calculation state to determine the tire wheel speed, including: in response to the current state of the tooth number calculation within the time interval, the first weight is greater than the second weight, and the difference between the first wheel speed and the second wheel speed is less than a preset synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed; in response to the current state of the tooth spacing time calculation, the second weight is greater than the first weight, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state within the time interval to use the second wheel speed as the tire wheel speed.

[0009] In some embodiments, determining the tire wheel speed based on the wheel speed information further includes: in response to the current tooth spacing time calculation state, the fluctuation of the first wheel speed is within the preset first fluctuation threshold, switching to the vehicle speed keeping mode, so that the first wheel speed is used as the tire wheel speed and remains unchanged. In response to the current time interval tooth number calculation state, the fluctuation of the second wheel speed is within the preset second fluctuation threshold, switching to the vehicle speed keeping mode, so that the second wheel speed is used as the tire wheel speed and remains unchanged. In response to the current speed keeping mode, the tooth spacing time sampling signal meets the preset continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state, so that the first wheel speed is used as the tire wheel speed. In response to the current speed keeping mode, the tooth number sampling signal within the time interval meets the preset continuous existence condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state within the time interval to select the second wheel speed as the tire wheel speed.

[0010] In some embodiments, determining the tire wheel speed based on the wheel speed information further includes: in response to the current state of calculating the number of teeth within the time interval, the sampling signal of the number of teeth within the time interval does not meet the continuous existence condition, switching to a preset backup mode, so as to convert using the preset speed and reduction ratio of the drive motor to obtain the tire wheel speed. In response to the current state of calculating the tooth spacing time, the tooth spacing time sampling signal does not meet the continuous stability condition, switching to the backup mode, so as to convert using the speed and reduction ratio of the drive motor to obtain the tire wheel speed. In response to the current state of the backup mode, the tooth spacing time sampling signal meets the continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state, so as to use the first wheel speed as the tire wheel speed. In response to the current state of the backup mode, the tooth number sampling signal within the time interval meets the continuous existence condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state within the time interval, so as to use the second wheel speed as the tire wheel speed.

[0011] In some embodiments, determining the tire wheel speed based on the wheel speed information further includes: in response to the current vehicle speed holding mode, the tooth spacing time is greater than or equal to the preset third time period, or the number of teeth in the time interval remains unchanged in the preset fourth time period, switching to the preset vehicle speed zeroing mode to set the tire wheel speed to zero. In response to the current vehicle speed zeroing mode, the tooth spacing time sampling signal meets the continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

[0012] In some embodiments, the tooth spacing time sampling signal satisfies a preset continuous stability condition, including: analyzing the tooth spacing time sampling signal to obtain the tooth spacing time within a number of consecutive controller operation cycles; in response to the tooth spacing time within a number of consecutive controller operation cycles not exceeding a preset range jump, and the tooth spacing time within a preset first time period remains updated, determining that the tooth spacing time sampling signal satisfies the continuous stability condition.

[0013] In some embodiments, the tooth number sampling signal within the time interval satisfies a preset continuous existence condition, including: analyzing the tooth number sampling signal within the time interval, obtaining that the number of teeth within the time interval is not zero and continues for a preset second time period, and determining that the tooth number sampling signal within the time interval satisfies the continuous existence condition.

[0014] In some embodiments, the tooth spacing time sampling signal is reliability checked to obtain a first weight corresponding to the first wheel speed, and the tooth number sampling signal within the time interval is reliability checked to obtain a second weight corresponding to the second wheel speed, including: performing a time difference check on the tooth spacing time sampling signal to obtain a first weight; performing a number of teeth check on the tooth number sampling signal within the time interval to obtain a second weight; in response to the first weight and the second weight being equal, obtaining the current vehicle speed, and adjusting the first weight and / or the second weight according to the current vehicle speed.

[0015] In some embodiments, the wheel speed square wave signal is processed to obtain corresponding wheel speed information, including: sampling the wheel speed square wave signal respectively to obtain a tooth spacing time sampling signal and a tooth number sampling signal within a time interval; in response to a rising edge or a falling edge of the wheel speed square wave signal, performing a tooth number accumulation operation to obtain the current number of teeth; obtaining the number of teeth within the time interval based on the current number of teeth and the number of teeth in the previous time interval; and obtaining the time between the rising edge and the adjacent falling edge to obtain the tooth spacing time.

[0016] In some embodiments, obtaining the effective rolling radius of a vehicle's tire includes: obtaining the roll angle, the maximum rolling radius of the tire, the crown radius, and the tire contact width; performing geometric calculations on the roll angle, the crown radius, and the tire contact width to obtain a geometric change in the rolling radius caused by the roll angle; and calculating the maximum rolling radius of the tire and the geometric change in the rolling radius to obtain the effective rolling radius of the tire.

[0017] In some embodiments, the tire wheel speed and the tire effective rolling radius are filtered and arbitrated to obtain the vehicle speed, including: in response to the strength of the received global positioning speed signal being greater than a preset strength threshold, the global positioning speed, the tire effective rolling radius and the tire wheel speed are filtered and arbitrated to obtain the vehicle speed.

[0018] Another technical solution adopted in the present application is: to provide an electronic device, the electronic device comprising: a memory for storing executable program code; a processor for calling and running the executable program code from the memory, so that the electronic device executes any one of the above vehicle speed detection methods.

[0019] Another technical solution adopted by the present application is: providing a computer-readable storage medium, the computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, implementing any of the above vehicle speed detection methods.

[0020] An embodiment of the present application provides a method for detecting a vehicle speed, which includes: obtaining an effective rolling radius of a vehicle tire; reading a wheel speed square wave signal of a gear ring hardware on a vehicle tire from a wheel speed sensor; processing the wheel speed square wave signal to obtain corresponding wheel speed information; wherein the wheel speed information includes at least one of a tooth spacing time, a tooth spacing time sampling signal, a number of teeth within a time interval, and a number of teeth within a time interval sampling signal; determining a tire wheel speed based on the wheel speed information; filtering and arbitrating the tire wheel speed and the tire effective rolling radius to obtain the vehicle speed.

[0021] By determining the tire wheel speed by utilizing at least one of the tooth spacing time, the tooth spacing time sampling signal, the number of teeth within the time interval, and the tooth number sampling signal within the time interval, the measurement accuracy of the wheel speed can be improved; by filtering and arbitrating the tire wheel speed and the tire effective rolling radius, the vehicle speed obtained can eliminate the influence of errors and abnormal data, adapt to complex working conditions such as roll turning, and thus improve the calculation accuracy of the vehicle speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a flow chart of the first embodiment of the vehicle speed detection method of the present application; Figure 2 It is a flow chart of the second embodiment of the vehicle speed detection method of the present application; Figure 3 It is a schematic diagram of the effective rolling radius of the tire of the vehicle speed detection method of the present application; Figure 4 It is a schematic diagram of a wheel speed calculation state machine of a vehicle speed detection method of the present application; Figure 5 It is a schematic diagram of the logic of calculating the speed of a motorcycle according to the vehicle speed detection method of the present application; Figure 6 It is an exemplary structural block diagram of an electronic device of the vehicle speed detection method of the present application; Figure 7 It is an exemplary structural block diagram of a computer-readable storage medium of the vehicle speed detection method of the present application. DETAILED DESCRIPTION

[0023] The present application is described in detail below with reference to the accompanying drawings and implementation methods.

[0024] In some embodiments, see Figure 1 , Figure 1 FIG. 1 is a flow chart of the first embodiment of the vehicle speed detection method of the present application. It should be noted that if there are substantially the same results, the method of the present application is not limited to the first embodiment. Figure 1 The process sequence shown is limited. Figure 1As shown, the vehicle speed detection method includes: Step S101, obtaining the effective rolling radius of the tire of the vehicle.

[0025] The vehicle may be an electric motorcycle. The tires of the vehicle include a front wheel and a rear wheel. The effective rolling radius of the tire may be the actual rolling radius of the tire in contact with the ground during the actual driving of the electric motorcycle. This embodiment may be applied to a motorcycle Main Vehicle Control Unit (MVCU).

[0026] As an example, since a motorcycle may roll over during driving, the position of the tire contact part will change, so that the rolling radius of the tire is not a static value, but a dynamically changing value. Therefore, by obtaining the effective rolling radius of the tire, the accuracy of the vehicle speed calculation can be improved.

[0027] In this embodiment, step S102 is performed after step S101 as an exemplary example. In other embodiments, step S101 and step S102 may be performed simultaneously, or step S102 may be performed before step S101.

[0028] Step S102, reading a wheel speed square wave signal of the ring gear hardware on the tire of the vehicle from the wheel speed sensor.

[0029] Among them, the wheel speed sensor can be used to measure the rotation speed of the tire. It can be installed near the wheel hub of the tire, and use magnetic induction or Hall effect to detect the rotation of the ring gear hardware, and output the wheel speed square wave signal of the ring gear hardware. The ring gear hardware can be a 48-hole signal ring gear hardware, a metal ring installed on the tire, with evenly distributed tooth grooves. When each tooth in the ring gear hardware passes through the wheel speed sensor, a high and low changing wheel speed square wave signal is generated. The wheel speed square wave signal can represent the rotation state of the tire, so the tire speed can be calculated by analyzing the square wave signal.

[0030] Step S103, processing the wheel speed square wave signal to obtain corresponding wheel speed information; wherein the wheel speed information includes at least one of tooth spacing time, tooth spacing time sampling signal, number of teeth in a time interval, and number of teeth sampling signal in a time interval.

[0031] The tooth spacing time may be the time taken by the wheel speed sensor to pass through adjacent tooth grooves in the gear ring hardware. The number of teeth in the time interval may be the number of teeth passing through the wheel speed sensor in a fixed time window. As an example, the number of teeth in the time interval may be the number of teeth in every 100 ms. In other embodiments, it may also be other time intervals, which is not limited in this embodiment.

[0032] As an illustrative example, since the speed of a motorcycle may be low or high during driving, when the tire speed is slow, the time for a single tooth of the gear ring hardware to pass is long. Using the tooth spacing time to calculate the tire wheel speed can improve the calculation accuracy. When the tire speed is fast, the time for a single tooth to pass becomes extremely short, and the error may increase. Using the number of teeth in the time interval to calculate the tire wheel speed can improve the calculation stability. Therefore, it is possible to make a judgment based on the tooth spacing time sampling signal and the tooth number sampling signal in the time interval to select the calculation state of the tooth spacing time or the calculation state of the number of teeth in the time interval to improve the calculation accuracy and calculation stability.

[0033] Step S104, determining the tire wheel speed based on the wheel speed information.

[0034] The tire wheel speed may be the tire rotation speed per minute calculated from the above signal. The tire speed is a core parameter for calculating the vehicle speed, and the final vehicle speed can only be obtained by combining the tire radius.

[0035] Step S105, filtering and arbitrating the tire wheel speed and the tire effective rolling radius to obtain the vehicle speed.

[0036] The tire wheel speed includes the front wheel speed and the rear wheel speed, and the tire effective rolling radius includes the front wheel effective rolling radius and the rear wheel effective rolling radius.

[0037] As an illustrative example, consider that when two or one of the wheels of a motorcycle is off the ground, the vehicle speed meter and the speed calculated by the controller are distorted and appear to be too large or too small; or when the motorcycle turns, the actual tire rolling radius becomes smaller due to the roll angle (Roll), and the wheel speed increases, while the tire rolling radius stored in the motorcycle instrument and other controllers is a fixed value, causing the vehicle speed meter and the speed calculated by the controller to be distorted and appear to be too large.

[0038] Therefore, the front wheel speed, rear wheel speed, front wheel effective rolling radius and rear wheel effective rolling radius can be substituted into the wheel circumference equation to calculate the front wheel speed and rear wheel speed. Then, the front wheel speed and rear wheel speed are input into the Kalman filter, and the actual speed of the vehicle is estimated using the calculation principle of prior + conditional probability = posterior probability, which can eliminate the influence of errors and abnormal data, thereby obtaining the actual speed of the vehicle.

[0039] This embodiment determines the tire wheel speed by utilizing at least one of the tooth spacing time, the tooth spacing time sampling signal, the number of teeth within the time interval, and the tooth number sampling signal within the time interval, thereby improving the measurement accuracy of the wheel speed; the vehicle speed obtained by filtering and arbitrating the tire wheel speed and the effective rolling radius of the tire can eliminate the influence of errors and abnormal data, thereby improving the calculation accuracy of the vehicle speed; and it is adaptable to complex working conditions such as roll turning.

[0040] See also Figure 2 , Figure 2 1 is a flow chart of a second embodiment of a method for detecting vehicle speed of the present application. The method comprises the following steps: Step S201, obtaining the roll angle, the maximum rolling radius of the tire, the crown radius and the contact width of the tire.

[0041] As an illustrative example, see Figure 3 , the roll angle can be the tilt angle of the motorcycle relative to the vertical direction when turning. The maximum rolling radius of the tire can be the nominal value at the factory, that is, the rolling radius of the motorcycle tire in an upright state. The crown radius can be the tread curvature radius of the tire, that is, the radius of the arc curve from the center to the sidewall of the tire surface, which will affect the ground contact shape of the tire at different roll angles. The tire contact width can be the lateral width of the tire in contact with the ground. When the motorcycle rolls, the contact position of the tire will shift accordingly.

[0042] Step S202, geometrically calculating the roll angle, the crown radius and the tire contact width to obtain a geometric change in the rolling radius caused by the roll angle.

[0043] The geometric variation of the rolling radius may be the variation in which the effective rolling radius of the tire decreases due to the contact point of the tire shifting from the center area of ​​the tire to the sidewall when the motorcycle rolls over.

[0044] Step S203, calculating the maximum rolling radius of the tire and the geometric variation of the rolling radius to obtain the effective rolling radius of the tire.

[0045] As an example, since the shape of the motorcycle tire is an arc-shaped crown surface, the motorcycle provides a lateral steering slip angle when it rolls, so that the motorcycle can resist lateral centrifugal force while turning. As the tire body roll angle increases, the part of the tire that contacts the ground also translates from the center line to the cross section of the tire crown, the tire's rotation radius also decreases accordingly, and the wheel speed increases. That is, the effective rolling radius of the tire when rolling will be smaller than the maximum rolling radius of the tire when upright.

[0046] Therefore, this embodiment constructs a mathematical geometric model of the tire in the software through MVCU, inputs tire-related parameters, and dynamically calculates the effective rolling radius of the tire in real time and replaces the maximum rolling radius of the tire, so that the accurate wheel speed can be obtained in subsequent calculations. The effective rolling radius A of the tire can be calculated by the following formula (1).

[0047] (1); Among them, A represents the effective rolling radius of the tire; B represents the crown radius; C represents the tire contact width; D represents the roll angle; and E represents the maximum rolling radius of the tire.

[0048] Step S204, reading the wheel speed square wave signal of the ring gear hardware on the tire of the vehicle from the wheel speed sensor.

[0049] The implementation and beneficial effects of step S204 may be the same as those of step S102.

[0050] Step S205 , sampling the wheel speed square wave signal respectively to obtain a tooth spacing time sampling signal and a tooth number sampling signal within a time interval.

[0051] As an illustrative example, since the square wave signal is a discrete pulse signal, it can be sampled so as to subsequently calculate a more stable wheel speed.

[0052] Step S206, in response to the rising edge or falling edge of the wheel speed square wave signal, perform a tooth number accumulation operation to obtain the current tooth number.

[0053] As an illustrative example, since the 48-hole signal ring gear hardware has a total of 48 teeth, the wheel speed square wave signal has a total of 48 rising edges and 48 falling edges, and the high level and low level read by the 48-hole signal ring gear hardware and the wheel speed sensor signal square wave in the oscilloscope are consistent.

[0054] Therefore, each rising and falling edge of the wheel speed square wave signal can be counted as a tooth, that is, the 48-hole signal gear ring hardware can be counted as 96 holes. This allows the counting to expand the calculation accuracy when the high level switches to the low level and the low level switches to the high level.

[0055] Step S207, obtaining the number of teeth in the time interval according to the current number of teeth and the number of teeth in the previous time interval.

[0056] As an example, when a motorcycle is running at high speed, the time interval between adjacent teeth will be shorter. Therefore, a calculation method of counting multiple teeth in a time window can be used, that is, the accumulated current number of teeth minus the number of teeth in the previous time interval can be used to obtain the number of teeth in the time interval.

[0057] As an exemplary explanation, the time interval may be 100ms, and in other embodiments, it may be other time intervals. For example, the number of up and down level jumps of the wheel speed square wave signal may be counted, and each time a low-to-high or high-to-low level jump is detected, the count is +1, and the count is counted from 0 to 65535 and then returned to 0 to accumulate the count again. In this way, the count difference of every 100ms in the count can be intercepted and then converted into the corresponding wheel speed.

[0058] Step S208, acquiring the time between the rising edge and the adjacent falling edge to obtain the tooth spacing time.

[0059] As an example, when a motorcycle is running at a low speed, the time interval between teeth is long, and the wheel speed can be directly calculated by the passing time of a single tooth with a small error. Therefore, the passing time of adjacent teeth can be calculated, that is, the time distance difference between the rising edge and the falling edge.

[0060] Step S209, the tooth spacing time is used to calculate the wheel speed to obtain the first wheel speed, and the number of teeth in the time interval is used to calculate the wheel speed to obtain the second wheel speed.

[0061] Among them, the first wheel speed is the wheel speed calculated using the adjacent tooth pitch time; the second wheel speed is the wheel speed calculated using the number of teeth in the time interval. The units of the first wheel speed and the second wheel speed are rpm; the unit of the adjacent tooth pitch time is us.

[0062] As an example, the first wheel speed = 600000÷48÷adjacent tooth spacing time. The second wheel speed = (current tooth number - the number of teeth in the previous 100ms) × 600÷48.

[0063] Step S210, performing reliability check on the tooth spacing time sampling signal to obtain a first weight corresponding to the first wheel speed, and performing reliability check on the tooth number sampling signal within the time interval to obtain a second weight corresponding to the second wheel speed.

[0064] The first weight and the second weight are used by the wheel speed calculation state machine to select the optimal wheel speed. The first weight can be used to evaluate the stability of the first wheel speed calculated based on the tooth spacing time; the second weight can be used to evaluate the stability of the second wheel speed calculated based on the number of teeth within the time interval. Thus, the wheel speed calculation state machine can select the wheel speed data suitable for the current driving state as output according to the size of the two weights.

[0065] In some embodiments, the tooth spacing time sampling signal is subjected to a time difference check to obtain a first weight; the tooth number sampling signal within the time interval is subjected to a tooth number check to obtain a second weight; in response to the first weight and the second weight being equal, the current vehicle speed is obtained, and the first weight and / or the second weight is adjusted according to the current vehicle speed.

[0066] Among them, the time difference check can determine whether the data is stable by comparing the time changes of continuous tooth spacing. The number of teeth check can check whether the number of teeth in a fixed time window changes abnormally.

[0067] As an example, the first wheel speed calculated based on the tooth pitch time can reach an accuracy of 0.1km / h in the vehicle speed range of [0, 100]km / h. However, the accuracy above 100km / h will decrease with the increase of vehicle speed. When the speed is higher than 150km / h, the wheel speed accuracy will be difficult to meet 1km / h due to the small value of the adjacent tooth pitch time (unit: us) and the fluctuation of the gear ring hardware mechanics and the wheel speed square wave signal.

[0068] The second wheel speed calculated based on the number of teeth in the time interval has an accuracy of 1 km / h in the entire [0, 300] km / h speed range, and its accuracy is limited by the number of 48-hole signal gear ring hardware.

[0069] Therefore, when it is detected that the first weight and the second weight are equal, the first weight and / or the second weight can be adjusted according to the current vehicle speed, so that the corresponding calculation state can be switched to according to the first weight and the second weight. This method is conducive to improving the switching accuracy between the tooth number calculation state and the tooth spacing time calculation state within the switching time interval.

[0070] For example, when the vehicle is traveling at a low speed, the value of the first weight is increased. When the vehicle is traveling at a high speed, the value of the second weight is increased. The calculation method is dynamically adjusted according to the first weight and the second weight, so that the wheel speed can be accurately calculated within different speed ranges, thereby improving the accuracy and reliability of the vehicle speed calculation.

[0071] As an exemplary illustration, the boundary value between high speed and low speed can be set according to the configuration of the vehicle or the actual situation, for example, the boundary value range can be 100-150 km / h. In some embodiments, the boundary value can be any one of 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150 or a value between any two of them.

[0072] Step S211, based on the first weight and the second weight, the first wheel speed and the second wheel speed, switch to the corresponding calculation state to determine the tire wheel speed.

[0073] As an illustrative example, the switching between calculation states can be composed of relevant condition judgments to achieve the optimization of the vehicle speed calculation logic, and will not frequently jump at a constant speed or not return to zero when stopping, which can improve the accuracy and timeliness of wheel speed calculation.

[0074] In some embodiments, step S211 may include: switching to a corresponding calculation state to determine the tire wheel speed based on the first weight and the second weight, the first wheel speed and the second wheel speed through a preset wheel speed calculation state machine.

[0075] As an illustrative example, the wheel speed calculation state machine can be used to switch the corresponding calculation state to determine the tire wheel speed. In this way, the calculation of the tire wheel speed can be matched with the current vehicle running state, thereby improving the accuracy of the tire wheel speed calculation.

[0076] In some embodiments, see Figure 4 The calculation status includes the calculation status of the number of teeth within the time interval and the calculation status of the tooth spacing time.

[0077] As an illustrative example, the tooth spacing time calculation state can use the first wheel speed calculated based on the tooth spacing time as the tire wheel speed. The tooth number calculation state within the time interval can use the second wheel speed calculated based on the tooth number within the time interval as the tire wheel speed.

[0078] In some embodiments, step S211 may include: in response to the current state of calculating the number of teeth within a time interval, the first weight is greater than the second weight, and the difference between the first wheel speed and the second wheel speed is less than a preset synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

[0079] For illustrative examples, see Figure 4 , when the current state is the calculation state of the number of teeth within the time interval, the size of the first weight and the second weight is detected. When it is detected that the first weight is greater than the second weight, the reliability weight is selected as the tooth spacing time calculation state, indicating that the tooth spacing time calculation state is more suitable for the current driving state. The difference between the first wheel speed and the second wheel speed is detected. When the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, the inter-mode wheel speed synchronization check is 1, which can be used to improve the stability and smoothness of the wheel speed switching. When the above conditions are met, the state of calculating the number of teeth within the time interval can be switched to the state of calculating the tooth spacing time, so that the first wheel speed is used as the tire wheel speed.

[0080] In some embodiments, step S211 may include: in response to the current tooth spacing time calculation state, the second weight is greater than the first weight, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state within the time interval to use the second wheel speed as the tire wheel speed.

[0081] For illustrative examples, see Figure 4 , when the current state is the tooth spacing time calculation state, the size of the first weight and the second weight is detected. When it is detected that the second weight is greater than the first weight, the reliability weight is selected as the tooth number calculation state within the time interval, indicating that the tooth number calculation state within the time interval is more suitable for the current driving state. The difference between the first wheel speed and the second wheel speed is detected. When the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, the inter-mode wheel speed synchronization check is 1, which can be used to improve the stability and smoothness of the wheel speed switching. When the above conditions are met, the tooth spacing time calculation state can be switched to the tooth number calculation state within the time interval to use the second wheel speed as the tire wheel speed.

[0082] In some embodiments, step S211 may include: in response to the current state of calculating the number of teeth within a time interval, the first weight is greater than the second weight, the difference between the first wheel speed and the second wheel speed is less than a preset synchronization threshold, and the tooth spacing time sampling signal satisfies a preset continuous stability condition, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

[0083] For illustrative examples, see Figure 4 , when the current state is the calculation state of the number of teeth within the time interval, the size of the first weight and the second weight is detected. When it is detected that the first weight is greater than the second weight, the reliability weight is selected as the tooth spacing time calculation state, indicating that the tooth spacing time calculation state is more suitable for the current driving state. The difference between the first wheel speed and the second wheel speed is detected. When the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, that is, the inter-mode wheel speed synchronization check is 1, which can be used to improve the stability and smoothness of the wheel speed switching. The change of the tooth spacing time sampling signal is detected. When it is detected that the tooth spacing time sampling signal meets the continuous stability condition, the tooth spacing time sampling signal is 1, which can reduce the risk of misjudgment of the wheel speed of the electric motorcycle in the case of tire slippage, single wheel off the ground, etc. When the above conditions are met, it can be switched from the tooth number calculation state within the time interval to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

[0084] In some embodiments, step S211 may include: in response to the current tooth spacing time calculation state, the second weight is greater than the first weight, the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, and the tooth number sampling signal within the time interval meets the preset continuous existence condition, switching to the tooth number calculation state within the time interval to use the second wheel speed as the tire wheel speed.

[0085] For illustrative examples, see Figure 4 , when the current state is the tooth spacing time calculation state, the size of the first weight and the second weight is detected. When it is detected that the second weight is greater than the first weight, the reliability weight is selected as the tooth number calculation state within the time interval, indicating that the tooth number calculation state within the time interval is more suitable for the current driving state. The difference between the first wheel speed and the second wheel speed is detected. When the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, the inter-mode wheel speed synchronization check is 1, which can be used to improve the stability and smoothness of the wheel speed switching. The change of the tooth number sampling signal within the time interval is detected. When it is detected that the change of the tooth number sampling signal within the time interval meets the continuous existence condition, the tooth number sampling signal within the time interval is 1, which can reduce the risk of misjudgment of the wheel speed of the electric motorcycle in the case of tire slippage, single wheel off the ground, etc. When the above conditions are met, it can be switched from the tooth spacing time calculation state to the tooth number calculation state within the time interval to use the second wheel speed as the tire wheel speed.

[0086] Among them, the synchronization threshold, the first time period, and the second time period can be set according to actual conditions.

[0087] In some embodiments, step S104 may include steps S209 to S211 as described above, which are used to switch between the tooth number calculation state and the tooth spacing time calculation state within the time interval.

[0088] In some embodiments, step S104 may further include: in response to the current tooth spacing time calculation state, the fluctuation of the first wheel speed is within a preset first fluctuation threshold, switching to the vehicle speed keeping mode to use the first wheel speed as the tire wheel speed and keep it unchanged.

[0089] For illustrative examples, see Figure 4 When the wheel speed fluctuates within a very small fluctuation range, it is possible to switch from the tooth number calculation state or the tooth spacing time calculation state within the time interval to the vehicle speed holding mode and keep the wheel speed unchanged.

[0090] For example, in response to the current tooth spacing time calculation state, the fluctuation of the first wheel speed is detected and judged. When the fluctuation of the first wheel speed is within the preset first fluctuation threshold, that is, when the vehicle speed holding mode is 1, the tooth spacing time calculation state can be switched to the vehicle speed holding mode, and the first wheel speed is used as the tire wheel speed and remains unchanged. The excessive response to small fluctuations can be reduced, and the calculation burden of the wheel speed can be reduced.

[0091] In some embodiments, step S104 may further include: in response to the current state of calculating the number of teeth within the time interval, the fluctuation of the second wheel speed is within a preset second fluctuation threshold, switching to the vehicle speed keeping mode to use the second wheel speed as the tire wheel speed and keep it unchanged.

[0092] For example, see Figure 4 In response to the current state of calculating the number of teeth within the time interval, the fluctuation of the second wheel speed is detected and judged. When the fluctuation of the second wheel speed is within the preset second fluctuation threshold, that is, when the vehicle speed holding mode is 1, the state of calculating the number of teeth within the time interval can be switched to the vehicle speed holding mode, and the second wheel speed is used as the tire wheel speed and remains unchanged. The excessive response to small fluctuations can be reduced, and the calculation burden of the wheel speed can be reduced.

[0093] As an exemplary explanation, the first fluctuation threshold and the second fluctuation threshold can be set according to actual conditions, for example, within the range of -2 rpm to 2 rpm.

[0094] In some embodiments, step S104 may also include: in response to the current vehicle speed holding mode, the tooth spacing time sampling signal satisfies the preset continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

[0095] For illustrative examples, see Figure 4 When the vehicle speed is currently maintained in the vehicle speed holding mode and the wheel speed has obvious fluctuations, the vehicle speed holding mode can be switched to the tooth number calculation state or the tooth spacing time calculation state within the time interval, and the corresponding tire wheel speed can be determined.

[0096] For example, when the vehicle is in speed holding mode, the change of the tooth spacing time sampling signal is detected. When it is detected that the tooth spacing time sampling signal meets the preset continuous stability condition, the tooth spacing time sampling signal is 1, which can reduce the risk of misjudgment of the wheel speed of the electric motorcycle in the case of tire slippage, single wheel off the ground, etc. The difference between the first wheel speed and the second wheel speed is detected. When it is detected that the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, the inter-mode wheel speed synchronization check is 1, which can improve the stability and smoothness of the wheel speed switching. When the above conditions are met, the vehicle speed holding mode is switched to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

[0097] In some embodiments, the tooth spacing time sampling signal satisfies a preset continuous stability condition, including: analyzing the tooth spacing time sampling signal to obtain the tooth spacing time within a number of consecutive controller operation cycles; in response to the tooth spacing time within a number of consecutive controller operation cycles not exceeding a preset range jump, and the tooth spacing time within a preset first time period remains updated, determining that the tooth spacing time sampling signal satisfies the continuous stability condition.

[0098] As an illustrative example, if the tooth spacing time remains unchanged for a long time, it may be that the vehicle is stationary, slipping, or one wheel is off the ground. Therefore, by detecting that the tooth spacing time in a number of consecutive controller operation cycles has no physical slope jump beyond the range, the risk of drastic changes in the tooth spacing time due to abnormal signals can be reduced, and by detecting that the tooth spacing time in a number of consecutive controller operation cycles is dynamically updated within the first time period instead of being constant, the risk of long-term signal stagnation can be reduced.

[0099] As an exemplary illustration, a number of consecutive controller operation cycles and the first time period may be set according to actual conditions. For example, if the tooth spacing time within three consecutive controller operation cycles (5ms) does not jump beyond the range (physical slope), and the tooth spacing time within the first time period (380ms) is kept updated and is not a constant value, it is determined that the tooth spacing time sampling signal meets the continuous stability condition.

[0100] In some embodiments, step S104 may also include: in response to the current vehicle speed holding mode, the tooth number sampling signal within the time interval meets the preset continuous existence condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state within the time interval to select the second wheel speed as the tire wheel speed.

[0101] For example, see Figure 4, when the current vehicle speed holding mode is selected, the change of the tooth number sampling signal within the time interval is detected. When the tooth number sampling signal within the time interval is detected to meet the preset continuous existence condition, the tooth number sampling signal within the time interval is 1, which can reduce the risk of misjudgment of the wheel speed of the electric motorcycle in the case of tire slippage, single wheel off the ground, etc. The difference between the first wheel speed and the second wheel speed is detected. When it is detected that the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, the wheel speed synchronization check between modes is 1, which can improve the stability and smoothness of wheel speed switching. When the above conditions are met, the vehicle speed holding mode is switched to the tooth number calculation state within the time interval, so that the first wheel speed is used as the tire wheel speed.

[0102] In some embodiments, the tooth number sampling signal within the time interval satisfies a preset continuous existence condition, including: analyzing the tooth number sampling signal within the time interval, obtaining that the number of teeth within the time interval is not zero and continues for a preset second time period, and determining that the tooth number sampling signal within the time interval satisfies the continuous existence condition.

[0103] As an illustrative example, if the number of teeth in the time interval is not zero, it can be confirmed that there is a signal input in each time interval, and the number of teeth in the time interval is not zero for a second time period, which can improve the reliability of the signal. For example, if the number of teeth in 100ms is not 0 and lasts for a certain time of 280ms, it is determined that the tooth number sampling signal in the time interval meets the continuous existence condition, which can exclude accidental error signals or short-term interference.

[0104] In some embodiments, step S104 may further include: in response to the current tooth spacing time calculation state, the tooth spacing time sampling signal does not meet the continuous stability condition, switching to the backup mode to use the speed and reduction ratio of the drive motor for conversion to obtain the tire wheel speed.

[0105] For illustrative examples, see Figure 4 , when the current state is the tooth spacing time calculation state, the tooth spacing time sampling signal is detected, and it is detected that the tooth spacing time sampling signal does not meet the continuous stability condition, that is, the tooth spacing time sampling signal is 0, indicating that the current wheel speed sensor or signal gear ring is interfered or damaged, etc., resulting in the first wheel speed calculated based on the tooth spacing time being unreliable. Therefore, it is possible to switch from the tooth spacing time calculation state to the backup mode, and use the wheel speed converted from the drive motor speed and the reduction ratio as the tire wheel speed. This method can reduce the risk of system failure due to wheel speed sensor or signal gear ring failure and improve the fault tolerance rate.

[0106] In some embodiments, step S104 may also include: in response to the current state of calculating the number of teeth within the time interval, and the tooth number sampling signal within the time interval does not meet the continuous existence condition, switching to a preset backup mode to use the preset drive motor speed and reduction ratio for conversion to obtain the tire wheel speed.

[0107] For illustrative examples, see Figure 4 , when the current state is the calculation state of the number of teeth within the time interval, it is detected that the sampling signal of the number of teeth within the time interval does not meet the continuous existence condition, that is, the sampling signal of the number of teeth within the time interval is 0, indicating that the current wheel speed sensor or signal gear ring is interfered or damaged, etc., resulting in the second wheel speed calculated based on the number of teeth within the time interval being unreliable. Therefore, it is possible to switch from the state of calculating the number of teeth within the time interval to the backup mode, and use the wheel speed converted from the drive motor speed and the reduction ratio as the tire wheel speed. This method can reduce the risk of system failure due to failure of the wheel speed sensor or signal gear ring, and improve the fault tolerance rate.

[0108] In some embodiments, step S104 may also include: in response to the current backup mode, the tooth spacing time sampling signal meets the continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

[0109] For illustrative examples, see Figure 4 , when the current mode is backup, the tooth spacing time sampling signal, the difference between the first wheel speed and the second wheel speed are detected. When the tooth spacing time sampling signal meets the continuous stability condition and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, that is, the tooth spacing time sampling signal is 1, and the inter-mode wheel speed synchronization check is 1, indicating that the wheel speed sensor or signal gear ring has returned to normal. Therefore, the backup mode can be switched to the tooth spacing time calculation state, and the first wheel speed is used as the tire wheel speed.

[0110] In some embodiments, step S104 may further include: in response to the current backup mode, the tooth number sampling signal in the time interval meets the continuous existence condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state in the time interval to use the second wheel speed as the tire wheel speed. This method can reduce the dependence on the conversion model and improve the accuracy of the wheel speed.

[0111] For illustrative examples, see Figure 4, when the current mode is backup, the difference between the number of teeth sampling signal, the first wheel speed and the second wheel speed in the time interval is detected. If the number of teeth sampling signal meets the continuous existence condition in the time interval, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, that is, the number of teeth sampling signal in the time interval is 1, and the wheel speed synchronization check between modes is 1, it means that the wheel speed sensor or signal gear ring has returned to normal. Therefore, it is possible to switch from the backup mode to the number of teeth calculation state in the time interval, and use the first wheel speed as the tire wheel speed. This method can reduce the dependence on the conversion model and improve the accuracy of the wheel speed.

[0112] In some embodiments, step S104 may also include: in response to the current vehicle speed holding mode, the tooth spacing time is greater than or equal to the preset third time period, or the number of teeth in the time interval remains unchanged within the preset fourth time period, switching to the preset vehicle speed zeroing mode to set the tire wheel speed to zero.

[0113] For example, see Figure 4 , when the current vehicle speed holding mode is selected, the adjacent tooth pitch time can be detected. When the adjacent tooth pitch time is detected to be greater than or equal to the third time period, that is, the vehicle speed zeroing mode is 1, it means that the vehicle wheels have stopped rotating at this time, and the vehicle may have wheel slip or idling. Therefore, the vehicle speed holding mode can be switched to the vehicle speed zeroing mode to return the tire wheel speed to zero. This method can reduce the risk of misjudgment of the vehicle control system.

[0114] As an exemplary description, the third time period can be set according to actual conditions, for example, 200 ms.

[0115] For example, see Figure 4 , when the current vehicle speed holding mode is selected, the number of teeth in the time interval can be detected. When it is detected that the number of teeth in the time interval remains unchanged for the fourth time period, the vehicle speed zeroing mode is 1, indicating that the wheel has stopped rotating at this time, and the vehicle may be experiencing wheel slippage or idling. Therefore, the vehicle speed holding mode can be switched to the vehicle speed zeroing mode to return the tire wheel speed to zero. This method can reduce the risk of misjudgment of the vehicle control system.

[0116] As an exemplary description, the fourth time period can be set according to actual conditions, for example, 200 ms.

[0117] In some embodiments, step S104 may also include: in response to the current vehicle speed zeroing mode, the tooth spacing time sampling signal satisfies the continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

[0118] For illustrative examples, see Figure 4 , when the current vehicle speed is in zeroing mode, the difference between the tooth spacing time sampling signal, the first wheel speed and the second wheel speed can be detected. When it is detected that the tooth spacing time sampling signal meets the continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, that is, the tooth spacing time sampling signal is 1, and the inter-mode wheel speed synchronization check is 1, it means that the vehicle starts to start or moves slowly at this time. Therefore, it is possible to switch from the vehicle speed zeroing mode to the tooth spacing time calculation state. In this way, more accurate wheel speed data can be provided during the low-speed driving or starting stage of the vehicle, especially at low speeds, to improve the system's real-time response capability to wheel speed changes.

[0119] As an example, Figure 4 The switching between the tooth number calculation state, tooth spacing time calculation state, vehicle speed holding mode, backup mode, and vehicle speed zeroing mode within the time interval shown can be switched through the wheel speed calculation state machine. In this way, the optimal calculation method can be dynamically selected to improve the wheel speed calculation accuracy at low or high speeds; when the sensor is abnormal, the motor speed and reduction ratio are used to calculate the wheel speed to improve data availability; when the wheel slips or idles, switch to the vehicle speed zeroing mode to reduce the risk of misjudgment of the vehicle control system; when the first wheel speed or the second wheel speed fluctuates slightly, switch to the vehicle speed holding mode, which can reduce excessive response to small fluctuations and reduce the calculation burden of the wheel speed. At the same time, by using the wheel speed calculation state machine to encapsulate different calculation states and modes in independent states, the efficiency and convenience of maintenance and upgrades can be improved.

[0120] Step S212, in response to the strength of the received global positioning vehicle speed signal being greater than a preset strength threshold, the global positioning vehicle speed, the effective rolling radius of the tire and the tire wheel speed are filtered and arbitrated to obtain the vehicle speed.

[0121] The global positioning vehicle speed signal and the global positioning vehicle speed may be obtained through a vehicle-mounted intelligent terminal (T-Box), and the global positioning may be a global positioning system (GPS).

[0122] As an illustrative example, the front wheel speed, rear wheel speed, front wheel effective rolling radius and rear wheel effective rolling radius can be substituted into the wheel circumference equation to calculate the front wheel speed and rear wheel speed. Then, the front wheel speed, rear wheel speed and global positioning vehicle speed are input into the Kalman filter together, and the actual vehicle speed is estimated using the calculation principle of prior + conditional probability = posterior probability, which can eliminate the influence of errors and abnormal data, thereby obtaining the actual vehicle speed.

[0123] In an exemplary embodiment, see Figure 5. The front wheel of the motorcycle is equipped with a 48-hole signal gear ring hardware and a front wheel speed sensor. The front wheel speed square wave signal of the front wheel speed sensor is read through the MVCU, and the front wheel speed square wave signal is processed to obtain the tooth spacing time, tooth spacing time sampling signal, number of teeth in the time interval, and number of teeth sampling signal in the time interval after improving the accuracy; then, the tooth spacing time is used to calculate the wheel speed to obtain the first wheel speed of the front wheel; the number of teeth in the time interval is used to calculate the wheel speed to obtain the second wheel speed of the front wheel; the tooth spacing time sampling signal is checked for reliability to obtain the first weight corresponding to the first wheel speed of the front wheel; the number of teeth sampling signal in the time interval is checked for reliability to obtain the second weight corresponding to the second wheel speed of the front wheel; then, the first wheel speed, the first weight, the second wheel speed, and the second weight are input into the front wheel speed calculation state machine for state switching, and the front wheel speed is output; at the same time, the roll angle of the motorcycle and the front wheel tire size parameters can be calculated to obtain the effective rolling radius of the front wheel. Similarly, the rear wheel tire can also be described above to obtain the rear wheel speed and the rear wheel effective rolling radius.

[0124] At the same time, the global positioning vehicle speed signal is obtained, and whether the strength of the global positioning vehicle speed signal is sufficient is detected; if the strength is sufficient, it means that the global positioning vehicle speed is valid, and if the strength is insufficient, it means that the global positioning vehicle speed is invalid.

[0125] When the global positioning speed is valid, the front wheel speed, the front wheel effective rolling radius, the global positioning speed, the rear wheel speed and the rear wheel effective rolling radius are input into the Kalman filter for filtering and speed arbitration to obtain the real speed of the motorcycle; when the global positioning speed is invalid, the front wheel speed, the front wheel effective rolling radius, the rear wheel speed and the rear wheel effective rolling radius are input into the Kalman filter for filtering and speed arbitration to obtain the real speed of the motorcycle.

[0126] In this embodiment, the first wheel speed is obtained by calculating the tooth spacing time, the second wheel speed is obtained by calculating the number of teeth in the time interval, and the tooth spacing time sampling signal and the tooth number sampling signal in the time interval are respectively checked for reliability to obtain a first weight corresponding to the first wheel speed and a second weight corresponding to the second wheel speed, and then the first wheel speed, the second wheel speed, the first weight and the second weight are input into the wheel speed calculation state machine for calculation state switching, and the tire wheel speed is determined from the first wheel speed and the second wheel speed, which can reduce the risk of distortion of the vehicle instrument speed or the controller calculating the vehicle speed when at least one wheel of the electric motorcycle leaves the ground or slips; at the same time, the tire wheel speed and the effective rolling radius of the tire are filtered and arbitrated to reduce the risk of the actual tire rolling radius becoming smaller due to the roll angle when the vehicle turns, and improve the accuracy of vehicle speed detection, so as to adapt to complex working conditions such as tire slipping, single wheel leaving the ground, and roll turning lights, for example, it is applied to advanced chassis control, intelligent driving, safe driving, path prediction and other functions. In addition, the MVCU and T-Box GPS data can be fused to more accurately calculate the motorcycle's true speed and improve vehicle control accuracy compared to the traditional solution that simply relies on the drive wheel speed to convert the vehicle speed.

[0127] See also Figure 6 , Figure 6 FIG. 1 is an exemplary structural block diagram of an electronic device of the vehicle speed detection method of the present application. Figure 6 As shown, the electronic device 600 of the present application may include a processor 601 and a memory 602, wherein the processor 601 and the memory 602 communicate with each other via a bus. The memory 602 stores program instructions for detecting vehicle speed, and when the program instructions are executed by the processor 601, the processor executes the above-mentioned related method steps to implement a vehicle speed detection method in the above-mentioned embodiment.

[0128] See also Figure 7 , Figure 7 is an exemplary structural block diagram of a computer-readable storage medium of the vehicle speed detection method of the present application. Figure 7 As shown, the computer-readable storage medium 700 stores a computer program 701. When the computer program 701 is executed by a processor on a computer, the computer executes the above-mentioned related method steps to implement a vehicle speed detection method in the above-mentioned embodiment.

[0129] The above scheme obtains the effective rolling radius of the vehicle's tire; reads the wheel speed square wave signal of the gear ring hardware on the vehicle's tire from the wheel speed sensor; processes the wheel speed square wave signal to obtain corresponding wheel speed information; wherein the wheel speed information includes at least one of the tooth spacing time, the tooth spacing time sampling signal, the number of teeth in the time interval and the number of teeth in the time interval sampling signal; determines the tire wheel speed based on the wheel speed information; filters and arbitrates the tire wheel speed and the tire effective rolling radius to obtain the vehicle speed.

[0130] By determining the tire wheel speed by utilizing at least one of the tooth spacing time, the tooth spacing time sampling signal, the number of teeth within the time interval, and the tooth number sampling signal within the time interval, the measurement accuracy of the wheel speed can be improved; by filtering and arbitrating the tire wheel speed and the tire effective rolling radius, the vehicle speed obtained can eliminate the influence of errors and abnormal data, and adapt to complex working conditions such as roll turning, thereby improving the calculation accuracy of the vehicle speed.

[0131] In the several embodiments provided in the present application, it should be understood that the disclosed methods, electronic devices and storage media can be implemented in other ways. For example, the device implementation described above is only schematic. For example, the division of modules or units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0132] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0133] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0134] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor to execute all or part of the steps of the vehicle speed detection method in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0135] The above are only implementation methods of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for detecting vehicle speed, characterized in that: The vehicle speed detection method comprises: Get the effective rolling radius of the vehicle's tires; Reading a wheel speed square wave signal of the ring gear hardware on the tire of the vehicle from a wheel speed sensor; Processing the wheel speed square wave signal to obtain corresponding wheel speed information, wherein the wheel speed information includes at least one of tooth spacing time, tooth spacing time sampling signal, number of teeth in a time interval, and number of teeth sampling signal in a time interval; determining a tire wheel speed based on the wheel speed information; The tire wheel speed and the tire effective rolling radius are filtered and arbitrated to obtain the vehicle speed.

2. The vehicle speed detection method according to claim 1, characterized in that: The determining the tire wheel speed based on the wheel speed information includes: The tooth spacing time is used to calculate the wheel speed to obtain the first wheel speed, and the number of teeth in the time interval is used to calculate the wheel speed to obtain the second wheel speed; Performing reliability check on the tooth spacing time sampling signal to obtain a first weight corresponding to the first wheel speed, and performing reliability check on the tooth number sampling signal within the time interval to obtain a second weight corresponding to the second wheel speed; Based on the magnitude of the first weight and the second weight, the first wheel speed and the second wheel speed, the corresponding calculation state is switched to determine the tire wheel speed.

3. The vehicle speed detection method according to claim 2, characterized in that: The calculation state includes the calculation state of the number of teeth in the time interval and the calculation state of the tooth spacing time; The step of switching to a corresponding calculation state based on the first weight and the second weight, the first wheel speed and the second wheel speed to determine the tire wheel speed includes: In response to the current tooth number calculation state within the time interval, the first weight is greater than the second weight, and the difference between the first wheel speed and the second wheel speed is less than a preset synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed; In response to the current tooth spacing time calculation state, the second weight is greater than the first weight, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state within the time interval to use the second wheel speed as the tire wheel speed.

4. The method for detecting vehicle speed according to claim 3, characterized in that: The step of determining the tire wheel speed based on the wheel speed information further includes: In response to the current tooth spacing time calculation state, the fluctuation of the first wheel speed is within a preset first fluctuation threshold, switching to a preset vehicle speed keeping mode to use the first wheel speed as the tire wheel speed and keep it unchanged; In response to the current state of calculating the number of teeth within the time interval, the fluctuation of the second wheel speed is within a preset second fluctuation threshold, switching to the vehicle speed keeping mode to use the second wheel speed as the tire wheel speed and keep it unchanged; In response to the current vehicle speed holding mode, the tooth spacing time sampling signal meets the preset continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed; In response to the current vehicle speed holding mode, the tooth number sampling signal within the time interval meets the preset continuous existence condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state within the time interval to select the second wheel speed as the tire wheel speed.

5. The vehicle speed detection method according to claim 4, characterized in that: The step of determining the tire wheel speed based on the wheel speed information further includes: In response to the current state of calculating the number of teeth in the time interval, the sampling signal of the number of teeth in the time interval does not meet the continuous existence condition, switching to a preset backup mode to convert the preset speed and reduction ratio of the drive motor to obtain the tire wheel speed; In response to the tooth spacing time calculation state being currently, the tooth spacing time sampling signal does not meet the continuous stability condition, switching to the backup mode to convert the rotation speed and reduction ratio of the drive motor to obtain the tire wheel rotation speed; In response to the current backup mode, the tooth spacing time sampling signal meets the continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed; In response to the current backup mode, the tooth number sampling signal within the time interval meets the continuous existence condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth number calculation state within the time interval to use the second wheel speed as the tire wheel speed.

6. The method for detecting vehicle speed according to claim 4, characterized in that: The step of determining the tire wheel speed based on the wheel speed information further includes: In response to the current vehicle speed holding mode, the tooth spacing time is greater than or equal to a preset third time period, or the number of teeth in the time interval remains unchanged in a preset fourth time period, switching to a preset vehicle speed zeroing mode to set the tire wheel speed to zero; In response to the current vehicle speed zeroing mode, the tooth spacing time sampling signal satisfies the continuous stability condition, and the difference between the first wheel speed and the second wheel speed is less than the synchronization threshold, switching to the tooth spacing time calculation state to use the first wheel speed as the tire wheel speed.

7. The vehicle speed detection method according to claim 4, characterized in that: The tooth spacing time sampling signal meets the preset continuous stability conditions, including: Analyze the tooth spacing time sampling signal to obtain the tooth spacing time within a plurality of consecutive controller operation cycles; In response to the tooth spacing time not exceeding a preset range jump in a number of consecutive controller operation cycles and the tooth spacing time keeping updated in a preset first time period, it is determined that the tooth spacing time sampling signal satisfies the continuous stability condition.

8. The method for detecting vehicle speed according to claim 4, characterized in that: The tooth number sampling signal within the time interval meets the preset continuous existence condition, including: The tooth number sampling signal within the time interval is analyzed to obtain that the tooth number within the time interval is not zero and continues for a preset second time period, and it is determined that the tooth number sampling signal within the time interval meets the continuous existence condition.

9. The vehicle speed detection method according to claim 2, characterized in that: The step of performing reliability check on the tooth spacing time sampling signal to obtain a first weight corresponding to the first wheel speed, and performing reliability check on the tooth number sampling signal within the time interval to obtain a second weight corresponding to the second wheel speed includes: Performing a time difference check on the tooth spacing time sampling signal to obtain the first weight; Performing a tooth number check on the tooth number sampling signal within the time interval to obtain the second weight; In response to the first weight and the second weight being equal, a current vehicle speed is acquired, and the first weight and / or the second weight is adjusted according to the current vehicle speed.

10. The vehicle speed detection method according to claim 1, characterized in that: The processing of the wheel speed square wave signal to obtain corresponding wheel speed information includes: The wheel speed square wave signal is sampled respectively to obtain the tooth spacing time sampling signal and the tooth number sampling signal within the time interval; In response to the rising edge or falling edge of the wheel speed square wave signal, performing a tooth number accumulation operation to obtain a current tooth number; Obtaining the number of teeth in the time interval according to the current number of teeth and the number of teeth in the previous time interval; The time between the rising edge and the adjacent falling edge is acquired to obtain the tooth spacing time.

11. The vehicle speed detection method according to claim 1, characterized in that: The step of obtaining the effective rolling radius of the tire of the vehicle includes: Obtain the roll angle, maximum tire rolling radius, crown radius and tire contact width; Performing geometric calculation on the roll angle, the crown radius and the tire contact width to obtain a geometric change in rolling radius caused by the roll angle; The maximum rolling radius of the tire and the geometric variation of the rolling radius are calculated to obtain the effective rolling radius of the tire.

12. The vehicle speed detection method according to claim 1, characterized in that: The filtering and arbitration calculation of the tire wheel speed and the tire effective rolling radius to obtain the vehicle speed includes: In response to the strength of the received global positioning vehicle speed signal being greater than a preset strength threshold, the global positioning vehicle speed, the tire effective rolling radius and the tire wheel speed are filtered and arbitrated to obtain the vehicle speed.

13. An electronic device, characterized in that: The electronic device comprises: A memory for storing executable program codes; A processor is used to call and run the executable program code from the memory, so that the electronic device executes the vehicle speed detection method as described in any one of claims 1 to 12.

14. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the vehicle speed detection method according to any one of claims 1 to 12 is implemented.

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