Wheel slip rate determination method and system and electronic equipment

Abstract

The invention discloses a wheel slip rate determination method and system and electronic equipment, and different calculation modes are distinguished by using wheel center speeds and wheel rotation speeds in different numerical value ranges, so that the slip rate of a to-be-measured wheel is determined through the corresponding calculation modes. Therefore, the slip rate of the to-be-measured vehicle can be accurately determined regardless of the numerical values of the wheel center speed and the wheel rotation speed, and the calculation accuracy is ensured.

Description

Technical Field

[0001] The present application relates to the field of vehicle dynamics, and in particular to a method, system and electronic device for determining a wheel slip rate. Background Art

[0002] Wheel slip rate refers to the ratio of relative slip between the wheel and the ground when the vehicle is braking or driving. Accurate determination of wheel slip rate is crucial to the vehicle's driving performance, safety and handling stability.

[0003] The theoretical formula for calculating wheel slip is to divide the difference between wheel rotational speed and wheel center speed by the maximum of the two. However, when the vehicle is in low-speed motion, the denominator in the formula may be zero, making it impossible to calculate wheel slip. Summary of the Invention

[0004] In view of this, the present application provides a method, system, and electronic device for determining a wheel slip rate, the specific solutions of which are as follows:

[0005] A method for determining a wheel slip ratio, comprising:

[0006] Obtaining a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of the wheel to be tested;

[0007] determining a wheel center speed based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal, and determining a wheel rotational speed based on the wheel speed signal;

[0008] determining a calculation mode for the slip ratio of the wheel under test before low-pass filtering based on a numerical range of the wheel center speed and the wheel rotation speed, wherein different calculation modes correspond to different wheel center speeds and wheel rotation speeds;

[0009] determining a slip ratio of the wheel to be tested before low-pass filtering based at least on the calculation mode;

[0010] The slip ratio of the wheel to be tested is determined based on the slip ratio before low-pass filtering.

[0011] In a possible implementation, determining the slip ratio of the wheel to be tested before low-pass filtering based at least on the calculation mode includes:

[0012] If it is determined that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the first mode or the second mode, the second-order filter and the least squares array corresponding to the calculation mode, as well as the wheel center speed and the wheel rotation speed are calculated according to the calculation mode to determine the slip rate before low-pass filtering of the wheel to be tested;

[0013] If it is determined that the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is other than the first mode and the second mode, the slip ratio before low-pass filtering of the wheel to be tested is determined based on the calculation mode.

[0014] In one possible implementation, calculating the second-order filter and least squares array corresponding to the calculation mode, the wheel center speed, and the wheel rotation speed according to the calculation mode to determine the slip rate of the wheel under test before low-pass filtering includes:

[0015] If it is determined that the calculation mode is the first mode, selecting a larger value from the wheel center speed and the wheel rotation speed as an input of a first second-order filter, and obtaining an output of the first second-order filter based on the input of the first second-order filter;

[0016] using the difference between the wheel rotation speed and the wheel center speed as an input of a second second-order filter, and obtaining an output of the second second-order filter based on the input of the second second-order filter;

[0017] Updating a first least squares queue corresponding to the first mode based on the output of the first second-order filter, and updating a second least squares queue corresponding to the first mode based on the output of the second second-order filter;

[0018] The slip ratio of the wheel to be tested before low-pass filtering is determined based on the first least squares array and the second least squares array.

[0019] In a possible implementation, determining the slip rate of the wheel to be tested before low-pass filtering based on the first least squares array and the second least squares array includes:

[0020] determining a first least squares sum of squares based on the first least squares array;

[0021] determining a first least squares product sum based on the first least squares array and the second least squares array;

[0022] If it is determined that the first least squares sum is a non-zero value, determining the quotient of the first least squares product sum and the first least squares sum as the slip rate of the wheel to be tested before low-pass filtering;

[0023] If it is determined that the first least square sum is 0, it is determined that the slip rate of the wheel to be tested before low-pass filtering is 0.

[0024] In one possible implementation, calculating the second-order filter and least squares array corresponding to the calculation mode, the wheel center speed, and the wheel rotation speed according to the calculation mode to determine the slip rate of the wheel under test before low-pass filtering includes:

[0025] If it is determined that the calculation mode is the second mode, selecting a smaller value from the wheel center speed and the wheel rotation speed as an input of a third second-order filter, and obtaining an output of the third second-order filter based on the input of the third second-order filter;

[0026] using the difference between the wheel rotation speed and the wheel center speed as an input of a fourth second-order filter, and obtaining an output of the fourth second-order filter based on the input of the fourth second-order filter;

[0027] Updating a third least squares queue corresponding to the second mode based on the output of the third second-order filter, and updating a fourth least squares queue corresponding to the second mode based on the output of the fourth second-order filter;

[0028] The slip ratio of the wheel to be tested before low-pass filtering is determined based on the third least squares array and the fourth least squares array.

[0029] In one possible implementation, if determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is other than the first mode and the second mode, determining the slip rate before low-pass filtering of the wheel to be tested based on the calculation mode includes:

[0030] If it is determined that the calculation mode is the third mode, determining that the slip rate of the wheel to be tested before low-pass filtering is 0;

[0031] If it is determined that the calculation mode is the fourth mode or the sixth mode, determining the slip rate of the wheel to be tested before low-pass filtering to be 1;

[0032] If it is determined that the calculation mode is the fifth mode or the seventh mode, determining the slip rate of the wheel to be tested before low-pass filtering to be -1;

[0033] The third mode, the fourth mode, the fifth mode, the sixth mode and the seventh mode are other modes except the first mode and the second mode.

[0034] In one possible implementation, determining a calculation mode for the slip rate of the wheel to be tested before low-pass filtering based on the numerical range of the wheel center speed and the wheel rotation speed includes:

[0035] If it is determined that the wheel rotation speed is greater than or equal to the first threshold and the wheel center speed is greater than or equal to 0, or if it is determined that the wheel rotation speed is greater than or equal to 0 and the wheel center speed is greater than or equal to the second threshold, determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the first mode;

[0036] If it is determined that the wheel rotation speed is less than or equal to the third threshold value and the wheel center speed is less than or equal to 0, or if it is determined that the wheel rotation speed is less than or equal to 0 and the wheel center speed is less than or equal to the fourth threshold value, determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the second mode;

[0037] The third threshold is a negative number of the first threshold, and the fourth threshold is a negative number of the second threshold.

[0038] In one possible implementation, determining a calculation mode for the slip rate of the wheel to be tested before low-pass filtering based on the numerical range of the wheel center speed and the wheel rotation speed includes:

[0039] If it is determined that the absolute value of the wheel rotation speed is less than or equal to the first threshold, and the absolute value of the wheel center speed is less than or equal to the second threshold, determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the third mode;

[0040] If it is determined that the wheel rotation speed is greater than or equal to the first threshold, and the wheel center speed is less than or equal to 0, determining that the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is the fourth mode;

[0041] If it is determined that the wheel rotation speed is greater than or equal to the third threshold and less than or equal to 0, and the wheel center speed is greater than or equal to the second threshold, determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the fifth mode;

[0042] If it is determined that the wheel rotation speed is less than or equal to the third mode, and the wheel center speed is greater than or equal to 0, determining that the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is the sixth mode;

[0043] If it is determined that the wheel rotation speed is greater than or equal to 0 and less than or equal to the first threshold, and the wheel center speed is less than or equal to the fourth threshold, determining that the calculation mode of the slip rate before low-pass filtering of the tested wheel is the seventh mode;

[0044] Among them, the negative of the first threshold is taken as the third threshold, the negative of the second threshold is taken as the fourth threshold, and the third mode, fourth mode, fifth mode, sixth mode and seventh mode are other modes except the first mode and the second mode.

[0045] A wheel slip ratio determination system comprising:

[0046] an obtaining unit, for obtaining a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of a wheel to be tested;

[0047] a first determining unit, configured to determine a wheel center speed based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal, and to determine a wheel rotational speed based on the wheel speed signal;

[0048] a second determining unit, configured to determine a calculation mode for the slip ratio before low-pass filtering of the wheel to be tested based on a numerical range of the wheel center speed and the wheel rotation speed, wherein different calculation modes correspond to different wheel center speeds and wheel rotation speeds;

[0049] a third determining unit, configured to determine the slip ratio of the wheel to be tested before low-pass filtering based at least on the calculation mode;

[0050] The fourth determining unit is configured to determine the slip rate of the wheel to be tested based on the slip rate before low-pass filtering.

[0051] An electronic device, comprising:

[0052] a processor configured to obtain a wheel angle signal, a longitudinal vehicle speed signal, a yaw rate signal, and a wheel speed signal of a wheel to be tested; determine a wheel center speed based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal, and determine a wheel rotational speed based on the wheel speed signal; determine a calculation mode for a pre-low-pass filtered slip ratio of the wheel to be tested based on a numerical range of the wheel center speed and the wheel rotational speed, wherein different wheel center speeds and wheel rotational speeds correspond to different calculation modes; determine the pre-low-pass filtered slip ratio of the wheel to be tested based on at least the calculation mode; and determine the slip ratio of the wheel to be tested based on the pre-low-pass filtered slip ratio;

[0053] The memory is used to store the program required by the processor to execute the above processing flow.

[0054] As can be seen from the above technical solutions, the wheel slip ratio determination method, system, and electronic device disclosed in this application obtain a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of a wheel under test; determine the wheel center velocity based on the longitudinal vehicle speed signal, the yaw angular velocity signal, and the wheel angle signal, and determine the wheel rotational speed based on the wheel speed signal; determine a calculation mode for the pre-low-pass filter slip ratio of the wheel under test based on the numerical ranges of the wheel center velocity and the wheel rotational speed, wherein different wheel center velocity and wheel rotational speed correspond to different calculation modes; determine the pre-low-pass filter slip ratio of the wheel under test based on at least the calculation mode; and determine the slip ratio of the wheel under test based on the pre-low-pass filter slip ratio. This solution utilizes wheel center velocity and wheel rotational speed in different numerical ranges to distinguish different calculation modes, so that the slip ratio of the wheel under test can be determined using the corresponding calculation mode. This ensures that the slip ratio of the vehicle under test can be accurately determined regardless of the numerical values of the wheel center velocity and the wheel rotational speed, thereby ensuring the accuracy of the calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0056] Figure 1 This is a flow chart of a method for determining a wheel slip rate disclosed in an embodiment of the present application;

[0057] Figure 2 A schematic diagram of an obtained signal and a result obtained by a wheel slip ratio determination method disclosed in an embodiment of the present application;

[0058] Figure 3 This is a flow chart of a method for determining a wheel slip rate disclosed in an embodiment of the present application;

[0059] Figure 4 A schematic diagram of a calculation mode corresponding to a wheel center speed and a wheel rotation speed when the values are in different value ranges disclosed in an embodiment of the present application;

[0060] Figure 5 This is a structural diagram of a wheel slip ratio determination system disclosed in an embodiment of the present application;

[0061] Figure 6 This is a schematic structural diagram of an electronic device disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0062] The following describes the embodiments of the present application in conjunction with the accompanying drawings. The terms used in the implementation methods of the present application are only used to explain the specific embodiments of the present application and are not intended to limit the present application.

[0063] The embodiments of the present application are described below in conjunction with the accompanying drawings. Those skilled in the art will appreciate that, with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0064] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, and this is merely a way of distinguishing the objects of the same attributes when describing them in the embodiments of the present application. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, so that the process, method, system, product or equipment comprising a series of units need not be limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0065] This application discloses a method for determining wheel slip rate, the flow chart of which is as follows: Figure 1 As shown, including:

[0066] Step S11, obtaining a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of a wheel to be tested;

[0067] Step S12: determining the wheel center speed based on the longitudinal vehicle speed signal, the yaw angular velocity signal, and the wheel angle signal, and determining the wheel rotational speed based on the wheel speed signal;

[0068] Step S13: determining a calculation mode for the slip ratio of the wheel under test before low-pass filtering based on the numerical ranges of the wheel center speed and the wheel rotation speed, wherein different calculation modes correspond to different wheel center speeds and wheel rotation speeds;

[0069] Step S14: determining the slip ratio of the wheel to be tested before low-pass filtering based at least on the calculation mode;

[0070] Step S15: Determine the slip rate of the wheel to be tested based on the slip rate before low-pass filtering.

[0071] Wheel slip rate refers to the ratio of relative slip between the wheel and the ground when the vehicle is braking or driving. Accurate determination of wheel slip rate is crucial to the vehicle's driving performance, safety and handling stability.

[0072] The theoretical formula for calculating wheel slip is to divide the difference between wheel rotational speed and wheel center speed by the maximum of the two. However, when the vehicle is in low-speed motion, the denominator in the formula may be zero, making it impossible to calculate wheel slip.

[0073] For example: when the wheel rotation speed and the wheel center speed are both 0, when calculating the slip rate according to the theoretical calculation formula of the wheel slip rate, a 0 / 0 situation will occur, and 0 cannot be used as the denominator; or, when the wheel rotation speed and the wheel center speed are close to 0, a large jump will occur; and when the vehicle slides on a slope, the wheel rotation speed may be positive and the wheel center speed may be negative, and problems will also arise when calculating the slip rate using the above theoretical calculation formula; similarly, when the wheel center speed is positive and the wheel rotation speed is negative, problems will also arise when calculating the slip rate using the above theoretical calculation formula.

[0074] Based on this, in this solution, different calculation modes are used for wheel center speeds and wheel rotation speeds in different numerical ranges to determine the slip rate of the wheel to be tested before low-pass filtering, so that the slip rate of the wheel to be tested can be determined regardless of the values of the wheel center speed and wheel rotation speed, thereby improving the accuracy of the slip rate calculation.

[0075] The wheel angle signal, longitudinal vehicle speed signal, yaw angular velocity signal and wheel speed signal of the wheel to be tested are obtained.

[0076] The wheel angle signal is acquired by the angle sensor and is measured in degrees. In this embodiment, it must be converted to radians (rad) before calculation. If the wheel to be measured is a non-steering wheel, the wheel angle signals of both the left and right wheels are 0. The longitudinal vehicle speed signal can be obtained by the vehicle speed estimation algorithm and is measured in kilometers per hour (km / h). In this embodiment, it must be converted to meters per second (m / s) before calculation. The yaw rate is acquired by the yaw rate sensor and is measured in radians per second (rad / s). The wheel speed signal is acquired by the wheel speed sensor and is measured in rotations per minute (rpm). In this embodiment, it must be converted to rad / s before calculation.

[0077] Among them, the wheel angle signal and wheel speed signal involve the left and right wheels, that is, the actual signals obtained include: the left wheel angle signal , right wheel angle signal , longitudinal vehicle speed signal , yaw rate signal , left wheel speed signal and the right wheel speed signal .

[0078] After obtaining the signals of the wheel to be tested, the wheel center speed and the wheel rotation speed can be determined based on the obtained signals. The determined wheel center speed includes the left wheel center speed. and the right wheel center speed The determined wheel rotation speed includes the left wheel rotation speed and the right wheel rotation speed .

[0079] Specifically, it can be determined using the following formula:

[0080] (Formula 1)

[0081] (Formula 2)

[0082] (Formula 3)

[0083] (Formula 4)

[0084] Among them, B is the wheelbase, the unit is meter (m), which is a constant parameter of the vehicle; R is the wheel rolling radius, the unit is meter (m), which is a constant parameter of the vehicle.

[0085] When determining the wheel center speed and the wheel rotation speed, the numerical ranges of the wheel center speed and the wheel rotation speed can be determined. Different numerical ranges correspond to different calculation modes, so as to ensure that no matter what the values of the wheel center speed and the wheel rotation speed are, there can be a corresponding calculation mode to calculate the slip rate of the wheel to be tested, thereby avoiding the situation where the same theoretical calculation formula is used to calculate the slip rate regardless of the values of the wheel center speed and the wheel rotation speed, resulting in calculation abnormalities.

[0086] Different calculation modes correspond to different calculation methods of the slip rate before low-pass filtering of the wheel to be tested. After determining the numerical range of the wheel center speed and the wheel rotation speed, the corresponding calculation mode is determined. Then, the slip rate before low-pass filtering of the wheel to be tested is determined using the determined calculation mode. , so that the slip rate of the wheel to be tested can be determined by using the slip rate before low-pass filtering .

[0087] The slip rate before low-pass filtering of the wheel to be tested Perform first-order low-pass filtering to obtain low-pass filtered variables , the low-pass filter variable Determine the slip rate of the wheel to be tested .

[0088] Among them, based on the slip rate before low-pass filtering Get the low-pass filter variable , can be determined using the following formula:

[0089] (Formula 5)

[0090] Wherein, T is the slip ratio calculation period in the wheel slip ratio determination method disclosed in this embodiment, that is, the slip ratio is calculated once in each slip ratio calculation period; is the low-pass filter time constant in seconds (s), obtained from a calibration test. It can be 0.1s, but can also be other values.

[0091] In determining the low-pass filter variable ,make , the slip rate can be obtained. The final slip rate can be referred to as the left wheel slip rate and right wheel slip rate .

[0092] The wheel slip ratio determination method disclosed in this embodiment obtains the collected signals and can obtain the wheel slip ratio, such as the left wheel slip ratio. and right wheel slip rate ,like Figure 2 , which is a schematic diagram of the obtained signal and the result obtained after the wheel slip ratio determination method.

[0093] It should be noted that before determining the wheel center speed and the wheel rotation speed, as long as it is determined that the slip rate of the wheel to be tested needs to be determined, an initialization process needs to be executed to initialize the queue or filter or other algorithm required to determine the slip rate of the wheel to be tested to ensure the accuracy of the calculation.

[0094] The wheel slip ratio determination method disclosed in this embodiment addresses the problem of theoretical calculations failing to calculate the slip ratio at low vehicle speeds or in special operating conditions such as rolling down a slope. Once the slip ratio is determined, it can be applied to tire force estimation, anti-skid control, and anti-lock braking.

[0095] The wheel slip rate determination method disclosed in this embodiment is applicable to any wheel of a vehicle. If the obtained wheel angle signal, longitudinal vehicle speed signal, yaw angular velocity signal, and wheel speed signal are related signals of the left and right front wheels, then the final slip rate obtained is the slip rate of the left and right front wheels; if the obtained wheel angle signal, longitudinal vehicle speed signal, yaw angular velocity signal, and wheel speed signal are related signals of the left and right rear wheels, then the final slip rate obtained is the slip rate of the left and right rear wheels.

[0096] In addition, if the embodiment involves the left wheel angle signal, it usually refers to the left front wheel angle signal and the left rear wheel angle signal. Correspondingly, if the left wheel speed signal is involved, it usually refers to the left front wheel speed signal and the left rear wheel speed signal, etc.; if the left wheel slip rate is involved, it usually refers to the left front wheel slip rate and the left rear wheel slip rate; the right wheel slip rate usually refers to the right front wheel slip rate and the right rear wheel slip rate. The left and right wheel slip rates usually refer to the longitudinal slip rates of the wheels.

[0097] The wheel slip determination method disclosed in this embodiment obtains a wheel angle signal, a longitudinal vehicle speed signal, a yaw rate signal, and a wheel speed signal of a wheel under test; determines the wheel center velocity based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal, and determines the wheel rotational speed based on the wheel speed signal; determines a calculation mode for the pre-low-pass filter slip of the wheel under test based on the numerical ranges of the wheel center velocity and the wheel rotational speed, wherein different wheel center velocity and wheel rotational speed correspond to different calculation modes; determines the pre-low-pass filter slip of the wheel under test based on at least the calculation mode; and determines the slip of the wheel under test based on the pre-low-pass filter slip. This embodiment utilizes wheel center velocity and wheel rotational speed within different numerical ranges to distinguish different calculation modes, so that the slip of the wheel under test can be determined using the corresponding calculation mode. This ensures that the slip of the vehicle under test can be accurately determined regardless of the numerical values of the wheel center velocity and the wheel rotational speed, thereby ensuring calculation accuracy.

[0098] This embodiment discloses a method for determining a vehicle slip rate, and its flow chart is as follows: Figure 3 As shown, including:

[0099] Step S31, obtaining a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of a wheel to be tested;

[0100] Step S32: determining the wheel center speed based on the longitudinal vehicle speed signal, the yaw angular velocity signal, and the wheel angle signal, and determining the wheel rotational speed based on the wheel speed signal;

[0101] Step S33: determining a calculation mode for the slip ratio of the wheel under test before low-pass filtering based on the numerical ranges of the wheel center speed and the wheel rotation speed, wherein different calculation modes correspond to different wheel center speeds and wheel rotation speeds;

[0102] Step S34: If it is determined that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the first mode or the second mode, the second-order filter and least squares array corresponding to the calculation mode, as well as the wheel center speed and the wheel rotation speed, are calculated according to the calculation mode to determine the slip rate before low-pass filtering of the wheel to be tested;

[0103] Step S35: if it is determined that the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is other than the first mode and the second mode, determining the slip ratio before low-pass filtering of the wheel to be tested based on the calculation mode;

[0104] Step S36: Determine the slip rate of the wheel to be tested based on the slip rate before low-pass filtering.

[0105] After obtaining the wheel angle signal, longitudinal vehicle speed signal, yaw angular velocity signal and wheel speed signal of the wheel to be tested, the wheel center speed and wheel rotation speed can be determined based on the wheel angle signal, longitudinal vehicle speed signal, yaw angular velocity signal and wheel speed signal. Thereafter, a corresponding calculation mode is determined using the numerical range of the wheel center speed and the wheel rotation speed. Different calculation modes are used to determine the slip rate of the wheel to be tested before low-pass filtering in different ways, so that the slip rate of the wheel to be tested can be determined after the slip rate before low-pass filtering is obtained.

[0106] The computing modes may include at least a first mode, a second mode, and other modes except the first mode and the second mode. The other modes may include a third mode, a fourth mode, a fifth mode, a sixth mode, and a seventh mode.

[0107] For the first and second modes, after determining the calculation mode, the wheel center speed and wheel rotational speed are used to further determine the slip ratio of the tested wheel before low-pass filtering using the corresponding second-order filter and least squares system. The first mode has its corresponding second-order filter and least squares system, and the second mode also has its corresponding second-order filter and least squares system. The second-order filter corresponding to the first mode is different from the second-order filter corresponding to the second mode, and the least squares system corresponding to the first mode is also different from the least squares system corresponding to the second mode.

[0108] For modes other than the first and second modes, as long as the calculation mode is determined, the slip rate before low-pass filtering can be directly determined without setting corresponding second-order filters and least squares queues for different calculation modes.

[0109] If the first mode is used to calculate the slip ratio before low-pass filtering based on the numerical range of the wheel center speed and the wheel rotation speed, the calculation can be specifically as follows:

[0110] If the calculation mode is determined to be the first mode, the larger value is selected from the wheel center speed and the wheel rotation speed as the input of the first second-order filter, and the output of the first second-order filter is obtained based on the input of the first second-order filter; the difference between the wheel rotation speed and the wheel center speed is used as the input of the second second-order filter, and the output of the second second-order filter is obtained based on the input of the second second-order filter; the first least squares queue corresponding to the first mode is updated based on the output of the first second-order filter, and the second least squares queue corresponding to the first mode is updated based on the output of the second second-order filter; the slip rate of the wheel to be tested before low-pass filtering is determined based on the first least squares queue and the second least squares queue.

[0111] When determining the calculation mode as the first mode, the wheel center speed must be and wheel rotation speed Select the maximum value as the input of the first and second order filters ,Right now:

[0112] (Formula 6)

[0113] The output of the first and second order filters can be:

[0114] (Formula 7)

[0115] in, 、 、 、 、 are all filter parameters, which can be obtained according to the following formula:

[0116] (Formula 8)

[0117] (Formula 9)

[0118] (Formula 10)

[0119] (Formula 11)

[0120] (Formula 12)

[0121] in, is the cutoff frequency, , is the cutoff frequency, which is determined according to a calibration experiment and may be 20 Hz. T is the calling period of the wheel slip ratio determination method disclosed in this embodiment in the controller, that is, the calculation period of the wheel slip ratio determination method disclosed in this embodiment.

[0122] After obtaining the output of the first and second order filters, the variables of the first and second order filters can be updated in sequence. , and then ;make , and then , so far the calculation of the first and second order filters is completed.

[0123] The wheel rotation speed can be Wheel center speed The difference between the two is used as the input of the second second-order filter ,Right now:

[0124] (Formula 13)

[0125] The output of the second second-order filter can be:

[0126] (Formula 14)

[0127] in, 、 、 、 、 These are all filter parameters, which can be determined based on Formula 8 to Formula 12 and will not be described in detail here.

[0128] After obtaining the output of the second second-order filter, the variables of the second second-order filter can be updated in sequence. , and then ;make , and then , so far the calculation of the second second-order filter is completed.

[0129] After the calculation of the first second-order filter is completed, the output of the first second-order filter can be used to update the first least squares queue. After the calculation of the second second-order filter is completed, the output of the second second-order filter can be used to update the second least squares queue, that is: let 、 、…、 、 ;make 、 、…、 、 .

[0130] After the first least squares array and the second least squares array are obtained, the slip ratio before low-pass filtering of the wheel to be tested can be determined using the obtained first least squares array and the second least squares array.

[0131] Specifically, the first least squares sum of squares is determined based on the first least squares queue; the first least squares product sum is determined based on the first least squares queue and the second least squares queue; if the first least squares sum of squares is determined to be a non-zero value, the quotient of the first least squares product sum and the first least squares sum of squares is determined as the slip rate of the wheel to be tested before low-pass filtering; if the first least squares sum of squares is determined to be 0, the slip rate of the wheel to be tested before low-pass filtering is determined to be 0.

[0132] Determine the first least squares sum of squares using the first least squares queue ,for:

[0133] (Formula 15)

[0134] Determine the first least squares product sum using the first least squares array and the second least squares array ,for:

[0135] (Formula 16)

[0136] Finally, determine the slip ratio before low-pass filtering ,for:

[0137] (Formula 17)

[0138] That is, in the first least squares sum of squares When it is 0, the slip rate before low-pass filtering is 0; the first least squares sum of squares When it is not 0, the first least squares product and and the first least squares sum of squares The quotient is determined as the slip rate before low-pass filtering .

[0139] In addition, if the second mode is used to calculate the slip ratio before low-pass filtering based on the numerical range of the wheel center speed and the wheel rotation speed, it can be specifically as follows:

[0140] If the calculation mode is determined to be the second mode, the smaller value is selected from the wheel center speed and the wheel rotation speed as the input of the third second-order filter, and the output of the third second-order filter is obtained based on the input of the third second-order filter; the difference between the wheel rotation speed and the wheel center speed is used as the input of the fourth second-order filter, and the output of the fourth second-order filter is obtained based on the input of the fourth second-order filter; the third least squares queue corresponding to the second mode is updated based on the output of the third second-order filter, and the fourth least squares queue corresponding to the second mode is updated based on the output of the fourth second-order filter; the slip rate of the wheel to be tested before low-pass filtering is determined based on the third least squares queue and the fourth least squares queue.

[0141] When determining the calculation mode to be the second mode, the wheel center speed must be first and wheel rotation speed Select the minimum value as the input of the third second-order filter ,Right now:

[0142] (Formula 18)

[0143] The output of the third second-order filter can be:

[0144] (Formula 19)

[0145] in, 、 、 、 、 These are all filter parameters, which can be determined based on Formula 8 to Formula 12 and will not be described in detail here.

[0146] After obtaining the output of the third second-order filter, the variables of the third second-order filter can be updated in sequence. , and then ;make , and then , so far the calculation of the third second-order filter is completed.

[0147] The wheel rotation speed can be Wheel center speed The difference between the two is used as the input of the fourth second-order filter ,Right now:

[0148] (Formula 20)

[0149] The output of the fourth second-order filter can be:

[0150] (Formula 21)

[0151] in, 、 、 、 、 These are all filter parameters, which can be determined based on Formula 8 to Formula 12 and will not be described in detail here.

[0152] After obtaining the output of the fourth second-order filter, the variables of the fourth second-order filter can be updated in sequence, so that , and then ;make , and then , the calculation of the fourth second-order filter is completed.

[0153] After the calculation of the third second-order filter is completed, the output of the third second-order filter can be used to update the third least squares queue. After the calculation of the fourth second-order filter is completed, the output of the fourth second-order filter can be used to update the fourth least squares queue, that is: let 、 、…、 、 ;make 、 、…、 、 .

[0154] After the third least squares array and the fourth least squares array are obtained, the slip rate of the wheel to be tested before low-pass filtering can be determined using the obtained third least squares array and the fourth least squares array.

[0155] Specifically, the second least squares sum of squares is determined based on the third least squares queue; the second least squares product sum is determined based on the third least squares queue and the fourth least squares queue; if the second least squares sum of squares is determined to be a non-zero value, the quotient of the second least squares product sum and the second least squares sum of squares is determined as the slip rate of the wheel to be tested before low-pass filtering; if the second least squares sum of squares is determined to be 0, the slip rate of the wheel to be tested before low-pass filtering is determined to be 0.

[0156] Determine the second least squares sum of squares using the third least squares array ,for:

[0157] (Formula 22)

[0158] Determine the first least squares product sum using the first least squares array and the second least squares array ,for:

[0159] (Formula 23)

[0160] Finally, determine the slip ratio before low-pass filtering ,for:

[0161] (Formula 24)

[0162] That is, the second least squares sum of squares When it is 0, the slip rate before low-pass filtering is 0; the second least squares sum of squares When it is not 0, the second least squares product and and the second least squares sum of squares The quotient is determined as the slip rate before low-pass filtering .

[0163] If the calculation mode is determined to be the third mode, the slip ratio before low-pass filtering can be directly determined is 0;

[0164] If the calculation mode is determined to be the fourth mode or the sixth mode, the slip rate before low-pass filtering of the wheel to be tested can be directly determined. is 1;

[0165] If the calculation mode is determined to be the fifth mode or the seventh mode, the slip rate before low-pass filtering of the wheel to be tested can be directly determined. is -1.

[0166] It should be noted that before starting all the steps of the wheel slip ratio determination method disclosed in this embodiment, initialization must be performed first. All second-order filters, first-order low-pass filters and least squares queues required for determining the slip ratio must be initialized. That is, the least squares queue ,make ,make ,make , where N is the least squares queue length, which can be determined through calibration experiments, such as 10; let the variables of each second-order filter be 0, and let the variables of the first-order low-pass filter be 0.

[0167] After determining the vehicle slip rate, it will jump to the step of determining the wheel center speed and wheel rotation speed in the wheel slip rate determination method disclosed in this embodiment, and select the calculation mode again. If at this time, the selected calculation mode is the first mode, all the second-order filters in the second mode and the related variables in the least squares queue need to be reset to 0, that is, initialized; if the selected calculation mode is the second mode, all the second-order filters in the first mode and the related variables in the least squares queue need to be reset to 0, that is, initialized; if other modes except the first mode and the second mode are selected, all the second-order filters in the first mode and the related variables in the least squares queue need to be reset to 0, and at the same time, all the second-order filters in the second mode and the related variables in the least squares queue need to be reset to 0 to ensure that the slip rate can be determined smoothly and accurately.

[0168] The wheel slip determination method disclosed in this embodiment obtains a wheel angle signal, a longitudinal vehicle speed signal, a yaw rate signal, and a wheel speed signal of a wheel to be tested; determines a wheel center speed based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal, and determines a wheel rotational speed based on the wheel speed signal; determines a calculation mode for the pre-low-pass filtering slip of the wheel to be tested based on the numerical ranges of the wheel center speed and the wheel rotational speed, wherein different wheel center speeds and wheel rotational speeds correspond to different calculation modes; if the calculation mode for the pre-low-pass filtering slip of the wheel to be tested is determined to be a first mode or a second mode, determines the pre-low-pass filtering slip of the wheel to be tested based on the calculation mode using a second-order filter and a least squares array corresponding to the calculation mode, as well as the wheel center speed and the wheel rotational speed; if the calculation mode for the pre-low-pass filtering slip of the wheel to be tested is determined to be a mode other than the first mode or the second mode, determines the pre-low-pass filtering slip of the wheel to be tested based on the calculation mode; and determines the slip of the wheel to be tested based on the pre-low-pass filtering slip. This embodiment utilizes wheel center speeds and wheel rotational speeds in different numerical ranges to distinguish different calculation modes, so that the slip rate of the wheel to be tested can be determined through the corresponding calculation mode. This ensures that regardless of the values of the wheel center speed and wheel rotational speed, the slip rate of the vehicle to be tested can be accurately determined, thereby ensuring the accuracy of the calculation.

[0169] Furthermore, in the wheel slip ratio determination method disclosed in this embodiment, the calculation mode for determining the slip ratio of the wheel to be tested before low-pass filtering based on the numerical range of the wheel center speed and the wheel rotation speed can be:

[0170] If it is determined that the wheel rotation speed is greater than or equal to the first threshold and the wheel center speed is greater than or equal to 0, or if it is determined that the wheel rotation speed is greater than or equal to 0 and the wheel center speed is greater than or equal to the second threshold, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the first mode; if it is determined that the wheel rotation speed is less than or equal to the third threshold and the wheel center speed is less than or equal to 0, or if it is determined that the wheel rotation speed is less than or equal to 0 and the wheel center speed is less than or equal to the fourth threshold, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the second mode; wherein, the negative of the first threshold is taken as the third threshold, and the negative of the second threshold is taken as the fourth threshold.

[0171] Among them, the first threshold is the wheel rotation speed stop threshold The second threshold is the wheel center speed stop threshold , the third threshold is the negative of the first threshold, that is, , the fourth threshold is the negative of the second threshold, that is, The first threshold and the second threshold are determined through calibration experiments and can be: m / s, m / s.

[0172] like Figure 4 , which is a schematic diagram of calculation modes corresponding to the values of the wheel center speed and the wheel rotation speed being in different value ranges.

[0173] If both meet as well as , or, satisfy both as well as ,like Figure 4 In the area where mode 1 is located, mode 1 corresponds to the first mode. At this time, it can be determined that the first mode is used to calculate the slip rate before low-pass filtering;

[0174] If both meet as well as , or, satisfy both as well as ,like Figure 4 In the area where mode 2 is located, mode 2 corresponds to the second mode. At this time, it can be determined that the second mode is used to calculate the slip rate before low-pass filtering.

[0175] Furthermore, the calculation mode includes not only the first mode and the second mode, but also a third mode, a fourth mode, a fifth mode, a sixth mode and a seventh mode.

[0176] If it is determined that the absolute value of the wheel rotation speed is less than or equal to the first threshold, and the absolute value of the wheel center speed is less than or equal to the second threshold, the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is determined to be the third mode; that is: as well as ,like Figure 4 In the area where mode 3 is located, mode 3 corresponds to the third mode. At this time, it can be determined that the third mode is used to calculate the slip rate before low-pass filtering;

[0177] If it is determined that the wheel rotation speed is greater than or equal to the first threshold and the wheel center speed is less than or equal to 0, the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is determined to be the fourth mode; that is, as well as ,like Figure 4 In the area where mode 4 is located, mode 4 corresponds to the fourth mode. At this time, it can be determined that the fourth mode is used to calculate the slip rate before low-pass filtering;

[0178] If it is determined that the wheel rotation speed is greater than or equal to the third threshold and less than or equal to 0, and the wheel center speed is greater than or equal to the second threshold, the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is determined to be the fifth mode; that is, as well as ,like Figure 4In the area where mode 5 is located, mode 5 corresponds to the fifth mode. At this time, it can be determined that the fifth mode is used to calculate the slip rate before low-pass filtering;

[0179] If it is determined that the wheel rotation speed is less than or equal to the third mode, and the wheel center speed is greater than or equal to 0, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the sixth mode; that is: as well as ,like Figure 4 In the area where mode 6 is located, mode 6 corresponds to the sixth mode. At this time, the sixth mode can be determined to be adopted;

[0180] If it is determined that the wheel rotation speed is greater than or equal to 0 and less than or equal to the first threshold, and the wheel center speed is less than or equal to the fourth threshold, the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is determined to be the seventh mode; that is, as well as ,like Figure 4 In the area where mode 7 is located, mode 7 corresponds to the seventh mode. At this time, it can be determined that the seventh mode is used to calculate the slip rate before low-pass filtering.

[0181] The corresponding calculation mode is determined by the wheel center speed and wheel rotation speed in different numerical ranges, thereby determining the slip rate of the wheel to be tested. Different calculation modes are used in different situations to determine the slip rate, avoiding the situation where the slip rate cannot be calculated under certain special working conditions.

[0182] This embodiment discloses a wheel slip ratio determination system, the structural diagram of which is shown in FIG. Figure 5 As shown, including:

[0183] an obtaining unit 51 , a first determining unit 52 , a second determining unit 53 , a third determining unit 54 and a fourth determining unit 55 .

[0184] The obtaining unit 51 is used to obtain the wheel angle signal, longitudinal vehicle speed signal, yaw angular velocity signal and wheel speed signal of the wheel to be tested;

[0185] The first determining unit 52 is configured to determine the wheel center speed based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal, and to determine the wheel rotation speed based on the wheel speed signal;

[0186] The second determining unit 53 is configured to determine a calculation mode for the slip ratio before low-pass filtering of the wheel to be tested based on the numerical ranges of the wheel center speed and the wheel rotation speed, wherein different calculation modes correspond to different wheel center speeds and wheel rotation speeds;

[0187] The third determining unit 54 is configured to determine the slip ratio before low-pass filtering of the wheel to be tested based at least on the calculation mode;

[0188] The fourth determining unit 55 is configured to determine the slip ratio of the wheel to be tested based on the slip ratio before low-pass filtering.

[0189] Furthermore, the third determining unit is configured to:

[0190] If it is determined that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the first mode or the second mode, the second-order filter and least squares queue corresponding to the calculation mode, as well as the wheel center speed and the wheel rotation speed, are calculated according to the calculation mode to determine the slip rate before low-pass filtering of the wheel to be tested; if it is determined that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is other than the first mode and the second mode, the slip rate before low-pass filtering of the wheel to be tested is determined based on the calculation mode.

[0191] Furthermore, the third determining unit is configured to:

[0192] If the calculation mode is determined to be the first mode, the larger value is selected from the wheel center speed and the wheel rotation speed as the input of the first second-order filter, and the output of the first second-order filter is obtained based on the input of the first second-order filter; the difference between the wheel rotation speed and the wheel center speed is used as the input of the second second-order filter, and the output of the second second-order filter is obtained based on the input of the second second-order filter; the first least squares queue corresponding to the first mode is updated based on the output of the first second-order filter, and the second least squares queue corresponding to the first mode is updated based on the output of the second second-order filter; the slip rate of the wheel to be tested before low-pass filtering is determined based on the first least squares queue and the second least squares queue.

[0193] Furthermore, the third determining unit is configured to:

[0194] Determine the first least squares sum of squares based on the first least squares queue; determine the first least squares product sum based on the first least squares queue and the second least squares queue; if it is determined that the first least squares sum of squares is a non-zero value, determine the quotient of the first least squares product sum and the first least squares sum of squares as the slip rate of the wheel to be tested before low-pass filtering; if it is determined that the first least squares sum of squares is 0, determine the slip rate of the wheel to be tested before low-pass filtering to be 0.

[0195] Furthermore, the third determining unit is configured to:

[0196] If the calculation mode is determined to be the second mode, the smaller value is selected from the wheel center speed and the wheel rotation speed as the input of the third second-order filter, and the output of the third second-order filter is obtained based on the input of the third second-order filter; the difference between the wheel rotation speed and the wheel center speed is used as the input of the fourth second-order filter, and the output of the fourth second-order filter is obtained based on the input of the fourth second-order filter; the third least squares queue corresponding to the second mode is updated based on the output of the third second-order filter, and the fourth least squares queue corresponding to the second mode is updated based on the output of the fourth second-order filter; the slip rate of the wheel to be tested before low-pass filtering is determined based on the third least squares queue and the fourth least squares queue.

[0197] Furthermore, the third determining unit is configured to:

[0198] If the calculation mode is determined to be the third mode, the slip rate of the wheel to be tested before low-pass filtering is determined to be 0; if the calculation mode is determined to be the fourth mode or the sixth mode, the slip rate of the wheel to be tested before low-pass filtering is determined to be 1; if the calculation mode is determined to be the fifth mode or the seventh mode, the slip rate of the wheel to be tested before low-pass filtering is determined to be -1; among them, the third mode, the fourth mode, the fifth mode, the sixth mode and the seventh mode are other modes except the first mode and the second mode.

[0199] Furthermore, the second determining unit is configured to:

[0200] If it is determined that the wheel rotation speed is greater than or equal to the first threshold and the wheel center speed is greater than or equal to 0, or if it is determined that the wheel rotation speed is greater than or equal to 0 and the wheel center speed is greater than or equal to the second threshold, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the first mode; if it is determined that the wheel rotation speed is less than or equal to the third threshold and the wheel center speed is less than or equal to 0, or if it is determined that the wheel rotation speed is less than or equal to 0 and the wheel center speed is less than or equal to the fourth threshold, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the second mode; wherein the third threshold is the negative of the first threshold, and the fourth threshold is the negative of the second threshold.

[0201] Furthermore, the second determining unit is configured to:

[0202] If it is determined that the absolute value of the wheel rotation speed is less than or equal to the first threshold value, and the absolute value of the wheel center speed is less than or equal to the second threshold value, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the third mode; if it is determined that the wheel rotation speed is greater than or equal to the first threshold value, and the wheel center speed is less than or equal to 0, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the fourth mode; if it is determined that the wheel rotation speed is greater than or equal to the third threshold value and less than or equal to 0, and the wheel center speed is greater than or equal to the second threshold value, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the fifth mode; if If it is determined that the wheel rotation speed is less than or equal to the third mode and the wheel center speed is greater than or equal to 0, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the sixth mode. If it is determined that the wheel rotation speed is greater than or equal to 0 and less than or equal to the first threshold value, and the wheel center speed is less than or equal to the fourth threshold value, the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is determined to be the seventh mode. Among them, the negative of the first threshold value is taken as the third threshold value, and the negative of the second threshold value is taken as the fourth threshold value. The third mode, the fourth mode, the fifth mode, the sixth mode, and the seventh mode are modes other than the first mode and the second mode.

[0203] The wheel slip ratio determination system disclosed in this embodiment is implemented based on the wheel slip ratio determination method disclosed in the above embodiment, which will not be described in detail here.

[0204] The wheel slip ratio determination system disclosed in this embodiment obtains a wheel angle signal, a longitudinal vehicle speed signal, a yaw rate signal, and a wheel speed signal of a wheel under test; determines the wheel center velocity based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal, and determines the wheel rotational speed based on the wheel speed signal; determines a calculation mode for the pre-low-pass filter slip ratio of the wheel under test based on the numerical ranges of the wheel center velocity and the wheel rotational speed, wherein different wheel center velocity and wheel rotational speed correspond to different calculation modes; determines the pre-low-pass filter slip ratio of the wheel under test based on at least one calculation mode; and determines the slip ratio of the wheel under test based on the pre-low-pass filter slip ratio. This embodiment utilizes wheel center velocity and wheel rotational speed within different numerical ranges to distinguish different calculation modes, so that the slip ratio of the wheel under test can be determined using the corresponding calculation mode. This ensures that the slip ratio of the vehicle under test can be accurately determined regardless of the numerical values of the wheel center velocity and the wheel rotational speed, thereby ensuring calculation accuracy.

[0205] This embodiment discloses an electronic device, the structural diagram of which is shown in FIG. Figure 6 As shown, including:

[0206] Processor 61 and memory 62.

[0207] The processor 61 is configured to obtain a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of a wheel to be tested; determine a wheel center velocity based on the longitudinal vehicle speed signal, the yaw angular velocity signal, and the wheel angle signal, and determine a wheel rotational speed based on the wheel speed signal; determine a calculation mode for a pre-low-pass filter slip ratio of the wheel to be tested based on a numerical range of the wheel center velocity and the wheel rotational speed, wherein different wheel center velocity and wheel rotational speed correspond to different calculation modes; determine a pre-low-pass filter slip ratio of the wheel to be tested based on at least the calculation mode; and determine a slip ratio of the wheel to be tested based on the pre-low-pass filter slip ratio.

[0208] The memory 62 is used to store the programs required by the processor to execute the above processing flow.

[0209] The electronic device disclosed in this embodiment is implemented based on the wheel slip ratio determination method disclosed in the above embodiment, which will not be described in detail here.

[0210] The electronic device disclosed in this embodiment obtains a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of a wheel to be tested; determines the wheel center velocity based on the longitudinal vehicle speed signal, the yaw angular velocity signal, and the wheel angle signal, and determines the wheel rotational speed based on the wheel speed signal; determines a calculation mode for the pre-low-pass filtering slip ratio of the wheel to be tested based on the numerical ranges of the wheel center velocity and the wheel rotational speed, wherein different wheel center velocity and wheel rotational speed correspond to different calculation modes; determines the pre-low-pass filtering slip ratio of the wheel to be tested based on at least one calculation mode; and determines the slip ratio of the wheel to be tested based on the pre-low-pass filtering slip ratio. This solution utilizes wheel center velocity and wheel rotational speed in different numerical ranges to distinguish different calculation modes, so that the slip ratio of the wheel to be tested can be determined using the corresponding calculation mode. This ensures that the slip ratio of the vehicle to be tested can be accurately determined regardless of the numerical values of the wheel center velocity and the wheel rotational speed, thereby ensuring the accuracy of the calculation.

[0211] An embodiment of the present application also provides a readable storage medium on which a computer program is stored. The computer program is loaded and executed by a processor to implement the various steps of the above-mentioned wheel slip rate determination method. The specific implementation process can refer to the description of the corresponding part of the above-mentioned embodiment, and will not be repeated in this embodiment.

[0212] This application also provides a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of an electronic device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the electronic device to perform the methods provided in various optional implementations of the aforementioned wheel slip ratio determination method or wheel slip ratio determination system. The specific implementation process can be found in the description of the corresponding embodiments above and is not elaborated on here.

[0213] It should also be noted that the device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed across multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. In addition, in the drawings of the device embodiments provided in this application, the connection relationship between the modules indicates that there is a communication connection between them, which can be specifically implemented as one or more communication buses or signal lines.

[0214] Through the description of the above embodiments, those skilled in the art can clearly understand that the present application can be implemented by means of software plus necessary general hardware, and of course can also be implemented by special hardware including application-specific integrated circuits, special CPUs, special memories, special components, etc. In general, all functions performed by computer programs can be easily implemented with corresponding hardware, and the specific hardware structures used to implement the same function can also be diverse, such as analog circuits, digital circuits or special circuits, etc. However, for the present application, software program implementation is a better implementation method in most cases. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a readable storage medium, such as a computer's floppy disk, USB flash drive, mobile hard disk, ROM, RAM, magnetic disk or optical disk, etc., and includes a number of instructions to enable a computer device (which can be a personal computer, training equipment, or network equipment, etc.) to execute the methods described in each embodiment of the present application.

[0215] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented by software, all or part of the embodiments may be implemented in the form of a computer program product.

[0216] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website, a computer, a training device or a data center by wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) mode to another website, computer, training device or data center. The computer-readable storage medium can be any available medium that a computer can store or a data storage device such as a training device, a data center that includes one or more available media integrations. The available medium can be a magnetic medium, (for example, a floppy disk, a hard disk, a tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid-state drive (SSD)).

Claims

1. A method for determining a wheel slip ratio, characterized in that: include: Obtaining a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of the wheel to be tested; determining a wheel center speed based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal, and determining a wheel rotational speed based on the wheel speed signal; determining a calculation mode for the slip ratio of the wheel under test before low-pass filtering based on a numerical range of the wheel center speed and the wheel rotation speed, wherein different calculation modes correspond to different wheel center speeds and wheel rotation speeds; determining a slip ratio of the wheel to be tested before low-pass filtering based at least on the calculation mode; The slip ratio of the wheel to be tested is determined based on the slip ratio before low-pass filtering.

2. The method according to claim 1, characterized in that The determining the slip ratio of the wheel to be tested before low-pass filtering based at least on the calculation mode includes: If it is determined that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the first mode or the second mode, the second-order filter and the least squares array corresponding to the calculation mode, as well as the wheel center speed and the wheel rotation speed are calculated according to the calculation mode to determine the slip rate before low-pass filtering of the wheel to be tested; If it is determined that the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is other than the first mode and the second mode, the slip ratio before low-pass filtering of the wheel to be tested is determined based on the calculation mode.

3. The method according to claim 2, characterized in that The method of calculating the second-order filter and the least squares array corresponding to the calculation mode, the wheel center speed, and the wheel rotation speed according to the calculation mode to determine the slip rate of the wheel to be tested before low-pass filtering includes: If it is determined that the calculation mode is the first mode, selecting a larger value from the wheel center speed and the wheel rotation speed as an input of a first second-order filter, and obtaining an output of the first second-order filter based on the input of the first second-order filter; using the difference between the wheel rotation speed and the wheel center speed as an input of a second second-order filter, and obtaining an output of the second second-order filter based on the input of the second second-order filter; Updating a first least squares queue corresponding to the first mode based on the output of the first second-order filter, and updating a second least squares queue corresponding to the first mode based on the output of the second second-order filter; The slip ratio of the wheel to be tested before low-pass filtering is determined based on the first least squares array and the second least squares array.

4. The method according to claim 3, characterized in that The determining the slip rate of the wheel to be tested before low-pass filtering based on the first least squares array and the second least squares array includes: determining a first least squares sum of squares based on the first least squares array; determining a first least squares product sum based on the first least squares array and the second least squares array; If it is determined that the first least squares sum is a non-zero value, determining the quotient of the first least squares product sum and the first least squares sum as the slip rate of the wheel to be tested before low-pass filtering; If it is determined that the first least square sum is 0, it is determined that the slip rate of the wheel to be tested before low-pass filtering is 0.

5. The method according to claim 2, characterized in that The method of calculating the second-order filter and the least squares array corresponding to the calculation mode, the wheel center speed, and the wheel rotation speed according to the calculation mode to determine the slip rate of the wheel to be tested before low-pass filtering includes: If it is determined that the calculation mode is the second mode, selecting a smaller value from the wheel center speed and the wheel rotation speed as an input of a third second-order filter, and obtaining an output of the third second-order filter based on the input of the third second-order filter; using the difference between the wheel rotation speed and the wheel center speed as an input of a fourth second-order filter, and obtaining an output of the fourth second-order filter based on the input of the fourth second-order filter; Updating a third least squares queue corresponding to the second mode based on the output of the third second-order filter, and updating a fourth least squares queue corresponding to the second mode based on the output of the fourth second-order filter; The slip ratio of the wheel to be tested before low-pass filtering is determined based on the third least squares array and the fourth least squares array.

6. The method according to claim 2, characterized in that If it is determined that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is other than the first mode and the second mode, determining the slip rate before low-pass filtering of the wheel to be tested based on the calculation mode includes: If it is determined that the calculation mode is the third mode, determining that the slip rate of the wheel to be tested before low-pass filtering is 0; If it is determined that the calculation mode is the fourth mode or the sixth mode, determining the slip rate of the wheel to be tested before low-pass filtering to be 1; If it is determined that the calculation mode is the fifth mode or the seventh mode, determining the slip rate of the wheel to be tested before low-pass filtering to be -1; The third mode, the fourth mode, the fifth mode, the sixth mode and the seventh mode are other modes except the first mode and the second mode.

7. The method according to claim 2, characterized in that The calculation mode of determining the slip rate of the wheel to be tested before low-pass filtering based on the numerical range of the wheel center speed and the wheel rotation speed includes: If it is determined that the wheel rotation speed is greater than or equal to the first threshold and the wheel center speed is greater than or equal to 0, or if it is determined that the wheel rotation speed is greater than or equal to 0 and the wheel center speed is greater than or equal to the second threshold, determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the first mode; If it is determined that the wheel rotation speed is less than or equal to the third threshold value and the wheel center speed is less than or equal to 0, or if it is determined that the wheel rotation speed is less than or equal to 0 and the wheel center speed is less than or equal to the fourth threshold value, determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the second mode; The third threshold is a negative number of the first threshold, and the fourth threshold is a negative number of the second threshold.

8. The method according to claim 2, characterized in that The calculation mode of determining the slip rate of the wheel to be tested before low-pass filtering based on the numerical range of the wheel center speed and the wheel rotation speed includes: If it is determined that the absolute value of the wheel rotation speed is less than or equal to the first threshold, and the absolute value of the wheel center speed is less than or equal to the second threshold, determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the third mode; If it is determined that the wheel rotation speed is greater than or equal to the first threshold, and the wheel center speed is less than or equal to 0, determining that the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is the fourth mode; If it is determined that the wheel rotation speed is greater than or equal to the third threshold and less than or equal to 0, and the wheel center speed is greater than or equal to the second threshold, determining that the calculation mode of the slip rate before low-pass filtering of the wheel to be tested is the fifth mode; If it is determined that the wheel rotation speed is less than or equal to the third mode, and the wheel center speed is greater than or equal to 0, determining that the calculation mode of the slip ratio before low-pass filtering of the wheel to be tested is the sixth mode; If it is determined that the wheel rotation speed is greater than or equal to 0 and less than or equal to the first threshold, and the wheel center speed is less than or equal to the fourth threshold, determining that the calculation mode of the slip rate before low-pass filtering of the tested wheel is the seventh mode; Among them, the negative of the first threshold is taken as the third threshold, the negative of the second threshold is taken as the fourth threshold, and the third mode, fourth mode, fifth mode, sixth mode and seventh mode are other modes except the first mode and the second mode.

9. A wheel slip ratio determination system, characterized in that: include: an obtaining unit, for obtaining a wheel angle signal, a longitudinal vehicle speed signal, a yaw angular velocity signal, and a wheel speed signal of a wheel to be tested; a first determining unit, configured to determine a wheel center speed based on the longitudinal vehicle speed signal, the yaw angular velocity signal, and the wheel angle signal, and to determine a wheel rotational speed based on the wheel speed signal; a second determining unit, configured to determine a calculation mode for the slip ratio before low-pass filtering of the wheel to be tested based on a numerical range of the wheel center speed and the wheel rotation speed, wherein different calculation modes correspond to different wheel center speeds and wheel rotation speeds; a third determining unit, configured to determine a slip ratio before low-pass filtering of the wheel to be tested based at least on the calculation mode; The fourth determining unit is configured to determine the slip rate of the wheel to be tested based on the slip rate before low-pass filtering.

10. An electronic device, characterized in that: include: a processor configured to obtain a wheel angle signal, a longitudinal vehicle speed signal, a yaw rate signal, and a wheel speed signal of a wheel to be tested; determine a wheel center speed based on the longitudinal vehicle speed signal, the yaw rate signal, and the wheel angle signal; and determine a wheel rotational speed based on the wheel speed signal; determining a calculation mode for the slip ratio before low-pass filtering of the wheel to be tested based on a numerical range of the wheel center speed and the wheel rotational speed, wherein different wheel center speeds and wheel rotational speeds correspond to different calculation modes; determining the slip ratio before low-pass filtering of the wheel to be tested based on at least the calculation mode; and determining the slip ratio of the wheel to be tested based on the slip ratio before low-pass filtering; The memory is used to store the program required by the processor to execute the above processing flow.

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