An automotive control method and device applied to a curve

Abstract

The present application relates to an automobile control method and device applied to a curve. The method includes: determining a curve coefficient of a current curve; calculating an acceleration gain based on the curve coefficient; when receiving a vehicle request torque or a request torque at a shaft end, and when a current speed parameter is within a preset speed range, allocating the vehicle request torque based on the acceleration gain, or compensating the request torque at the shaft end based on the acceleration gain to obtain a final required torque at the shaft end, where the shaft end includes a front axle and a rear axle; controlling a drive motor to respond to the final required torque at the shaft end. By adopting this method, the driving efficiency of an automobile on a curve can be improved.

Description

Technical Field

[0001] This application relates to the field of automotive control technology, and particularly to an automotive control method and device applied to a curve. Background Art

[0002] When an automobile turns, it mainly drives the steering gear through the steering wheel, and then makes the rack and pinion steering gear work, causing the front tie rod to swing left and right to make the front wheels generate an angle, thus realizing the turn. When the automobile is driving on a curve, the driver not only needs to control the steering wheel but also needs to control the vehicle speed.

[0003] When the steering wheel rotates too much and the vehicle speed is relatively high, bumps will occur. If the driver makes a sharp turn due to improper operation, it may also cause a safety accident. Therefore, the control of the vehicle on a curve is closely related to the comfort and safety of the vehicle occupants.

[0004] Currently, automobiles usually use the front-wheel steering method to control the vehicle's steering. During the turning process of the automobile, the driver may have difficulty taking into account both the driving stability and power performance of the automobile at the same time, resulting in low driving efficiency of the automobile on a curve. Summary of the Invention

[0005] Based on this, an automotive control method and device applied to a curve are provided to improve the driving efficiency of an automobile on a curve in the prior art.

[0006] In a first aspect, an automotive control method applied to a curve is provided. The method includes:

[0007] Determine the curve coefficient of the current curve;

[0008] Calculate the acceleration gain based on the curve coefficient;

[0009] When receiving the vehicle request torque or the request torque at the axle end, and the current speed parameter is within a preset speed range, allocate the vehicle request torque based on the acceleration gain, or compensate the request torque at the axle end based on the acceleration gain to obtain the final required torque at the axle end, where the axle end includes the front axle and the rear axle;

[0010] Control the drive motor to respond to the final required torque at the axle end.

[0011] Combined with the first aspect, in the first possible implementation manner of the first aspect, the step of determining the curve coefficient of the current curve includes:

[0012] Collect the lateral acceleration of the current vehicle perpendicular to the driving direction;

[0013] Obtain the lateral acceleration change rate according to the lateral acceleration;

[0014] Obtain a preset curve recognition threshold, and determine whether the product of the lateral acceleration and the change rate of the lateral acceleration is greater than the curve recognition threshold;

[0015] If it is, determine that the current vehicle is in a state of entering the current curve, and the curve coefficient of the current curve is the first coefficient;

[0016] If not, determine that the current vehicle is in a state of exiting the current curve, and the curve coefficient of the current curve is the second coefficient.

[0017] Combined with the first aspect, in the second implementable manner of the first aspect, the step of determining the curve coefficient of the current curve includes:

[0018] Collect the yaw angular velocity of the current vehicle;

[0019] Obtain the change rate of the yaw angular velocity according to the yaw angular velocity;

[0020] Obtain a preset curve recognition threshold, and determine whether the product of the yaw angular velocity and the change rate of the yaw angular velocity is greater than the curve recognition threshold;

[0021] If it is, determine that the current vehicle is in a state of entering the current curve, and the curve coefficient of the current curve is the first coefficient;

[0022] If not, determine that the current vehicle is in a state of exiting the current curve, and the curve coefficient of the current curve is the second coefficient.

[0023] Combined with the first aspect, in the third implementable manner of the first aspect, the step of calculating the acceleration gain based on the curve coefficient includes:

[0024] Collect the yaw angular velocity of the current vehicle and the lateral acceleration perpendicular to the driving direction horizontally;

[0025] Obtain the change rate of the lateral acceleration according to the lateral acceleration, and obtain the change rate of the yaw angular velocity according to the yaw angular velocity;

[0026] Obtain a preset first weight;

[0027] Based on the change rate of the lateral acceleration, the curve coefficient, and the first weight, obtain a first gain;

[0028] Based on the change rate of the yaw angular velocity, the curve coefficient, and the first weight, obtain a second gain;

[0029] Calculate the sum of the first gain and the second gain to obtain the acceleration gain.

[0030] Combined with the third implementable manner of the first aspect, in the fourth implementable manner of the first aspect, the step of obtaining the first gain based on the lateral acceleration change rate, the bend coefficient, and the first weight includes:

[0031] Obtain the road allowable acceleration;

[0032] According to the lateral acceleration and the road allowable acceleration, obtain the maximum allowable longitudinal acceleration in the driving direction, where the mathematical expression for obtaining the maximum allowable longitudinal acceleration includes:

[0033]

[0034] a xmax is the maximum allowable longitudinal acceleration, a g is the road allowable acceleration, a y is the lateral acceleration;

[0035] Obtain the first gain according to the product of the lateral acceleration change rate, the bend coefficient, the maximum allowable longitudinal acceleration, and the first weight.

[0036] Combined with the fourth implementable manner of the first aspect, in the fifth implementable manner of the first aspect, the step of obtaining the second gain based on the yaw rate change rate, the bend coefficient, and the first weight includes:

[0037] Obtain the second gain according to the yaw rate change rate, the bend coefficient, the maximum allowable longitudinal acceleration, and the first weight, where the mathematical expression for obtaining the second gain includes:

[0038]

[0039] a ωgain is the second gain, is the yaw rate change rate, W is the bend coefficient, a xmax is the maximum allowable longitudinal acceleration, F1 is the first weight.

[0040] Combined with the third implementable manner of the first aspect, in the sixth implementable manner of the first aspect, the step of distributing the vehicle's requested torque based on the acceleration gain to obtain the final required torque at the axle end includes:

[0041] Obtain a preset second weight;

[0042] Based on the acceleration gain and the second weight, obtain a gain distribution ratio;

[0043] Obtain a torque change amount according to the product of the gain distribution ratio and the vehicle's requested torque;

[0044] Obtain the final required torque of the front axle according to the difference between the vehicle's requested torque and the torque change amount;

[0045] Obtain the final required torque of the rear axle according to the sum of the vehicle's requested torque and the torque change amount.

[0046] Combined with the third implementable manner of the first aspect, in the seventh implementable manner of the first aspect, the step of compensating the requested torque of the axle end based on the acceleration gain to obtain the final required torque of the axle end includes:

[0047] Obtain the vehicle mass, wheel rolling radius of the current vehicle, and a preset second weight;

[0048] Obtain a gain distribution ratio based on the acceleration gain and the second weight;

[0049] Obtain the torque gain of the axle end according to the acceleration gain, the gain distribution ratio, the vehicle mass, and the wheel rolling radius, wherein the mathematical expression for obtaining the torque gain of the axle end includes:

[0050] T Fgain = a gain * a d * m * r

[0051] T Rgain = a gain *(1 - a gain )* m * r

[0052] T Fgain is the torque gain of the front axle, a gain is the acceleration gain, a d is the gain distribution ratio, m is the vehicle mass, r is the wheel rolling radius, T Rgain is the torque gain of the rear axle;

[0053] Superimpose the torque gain of the same axle end and the requested torque to obtain the final required torque of the axle end.

[0054] Combined with the sixth or seventh implementable manner of the first aspect, in the eighth implementable manner of the first aspect, the step of obtaining a gain distribution ratio based on the acceleration gain and the second weight includes:

[0055] Obtain a gain distribution ratio according to the lateral acceleration change rate, the bend coefficient, the yaw rate change rate, the acceleration gain, and the second weight, wherein the mathematical expression for obtaining the gain distribution ratio includes:

[0056]

[0057] a d is the gain distribution ratio, is the lateral acceleration change rate, W is the bend coefficient, F2 is the second weight, a gain is the acceleration gain, is the yaw rate change rate.

[0058] Combined with the first aspect, in the ninth implementable manner of the first aspect, before the step of receiving the vehicle's requested torque, it includes:

[0059] Collect the current driving speed;

[0060] Obtain the current throttle depth, and according to the current driving speed and the current throttle depth, obtain the vehicle's original required torque;

[0061] According to the current driving speed and the vehicle's original required torque, obtain the torque gradient;

[0062] Obtain the vehicle's requested torque according to the sum of the vehicle's original required torque and the torque gradient.

[0063] Combined with the first aspect, in the tenth implementable manner of the first aspect, the current speed parameter includes at least one of the yaw rate, the yaw rate change rate, and the lateral acceleration change rate perpendicular to the driving direction horizontally; the speed interval includes at least one of the first interval, the second interval, and the third interval; the first interval corresponds to the yaw rate, the second interval corresponds to the yaw rate change rate, and the third interval corresponds to the lateral acceleration change rate.

[0064] Second aspect, provide an automotive control device applied to a bend, characterized in that the device includes a vehicle controller, wherein the vehicle controller is used for:

[0065] Determine the bend coefficient of the current bend

[0066] Calculate the acceleration gain based on the bend coefficient;

[0067] When receiving the vehicle's requested torque or the requested torque at the axle end, and the current speed parameter is within a preset speed range, allocate the vehicle's requested torque based on the acceleration gain, or compensate the requested torque at the axle end based on the acceleration gain, to obtain the final required torque at the axle end, where the axle end includes the front axle and the rear axle;

[0068] Control the drive motor to respond to the final required torque at the axle end.

[0069] The above-mentioned vehicle control method and device applied to a curve determine the curve coefficient of the current curve; calculate the acceleration gain based on the curve coefficient; when receiving the vehicle's requested torque or the requested torque at the axle end, and the current speed parameter is within a preset speed range, allocate the vehicle's requested torque based on the acceleration gain, or compensate the requested torque at the axle end based on the acceleration gain, to obtain the final required torque at the axle end, where the axle end includes the front axle and the rear axle; control the drive motor to respond to the final required torque at the axle end. It can be seen that the above method realizes the real-time allocation of the vehicle's requested torque according to the actual situation of the curve and the driver's operation intention, or performs positive compensation or negative compensation on the requested torque at the axle end without affecting the original requested torque at the axle end, so as to realize the change of the vehicle's steering characteristics, improve the vehicle's entry and exit speeds of the curve, and stabilize the lateral acceleration, reduce the fluctuation of the yaw angular velocity, and effectively improve the stability and power performance of the vehicle when turning. Therefore, compared with the prior art, the above method improves the driving efficiency of the vehicle on the curve. Description of the Drawings

[0070] Figure 1 It is a schematic flow chart of a vehicle control method applied to a curve in an embodiment;

[0071] Figure 2 It is a structural block diagram of a vehicle control device applied to a curve in an embodiment; Detailed Embodiments

[0072] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0073] It should be noted that the diagrams provided in this embodiment only illustrate the basic concept of the present application schematically. Therefore, only the components related to the present application are shown in the diagrams, rather than being drawn according to the number, shape and size of the components in actual implementation. The type, quantity and proportion of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0074] The structures, proportions, sizes, etc. shown in the drawings of this specification are only used to match the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limiting conditions that the present application can be implemented. Therefore, they do not have substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects that the present application can produce and the purposes that can be achieved, should still fall within the scope that the technical content disclosed in the present application can cover.

[0075] The orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "middle", "longitudinal", "lateral", "horizontal", "inner", "outer", "radial", "circumferential", etc. cited in this specification is based on the orientation or positional relationship shown in the drawings, and is also only for the convenience of simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0076] In one embodiment, as Figure 1 shown, a vehicle control method applied to a curved road is provided. Taking the application of this method to a vehicle controller as an example, it includes the following steps:

[0077] S101: Determine the curve coefficient of the current curve.

[0078] Among them, the curve coefficient is used to indicate the influence degree of entering or exiting the curve on the vehicle request torque or the request torque at the axle end. This embodiment provides two ways to determine the curve coefficient. The first way is to determine the curve coefficient according to the lateral acceleration of the current vehicle, and the second way is to determine the curve coefficient according to the yaw rate of the current vehicle. Specifically:

[0079] Steps for determining a curve coefficient based on the lateral acceleration of a current vehicle include: collecting the lateral acceleration of the current vehicle perpendicular to the driving direction in the horizontal plane; obtaining a lateral acceleration change rate based on the lateral acceleration; obtaining a preset curve recognition threshold, and determining whether the product of the lateral acceleration and the lateral acceleration change rate is greater than the curve recognition threshold; if so, determining that the current vehicle is in a state of entering the current curve, and the curve coefficient of the current curve is a first coefficient; if not, determining that the current vehicle is in a state of exiting the current curve, and the curve coefficient of the current curve is a second coefficient. Among them, the lateral acceleration can be collected by setting a speed sensor on the current vehicle, and the speed sensor is used for collection; after the speed sensor collects at least two lateral accelerations, the lateral accelerations are transmitted to a vehicle controller, and the vehicle controller obtains the lateral acceleration change rate according to the ratio of the change amount between the two lateral accelerations to the time taken for this change amount. To make the value of the lateral acceleration change rate more accurate, the speed sensor can collect N lateral accelerations, and the vehicle controller can calculate N - 1 lateral acceleration change rates based on these N lateral accelerations, and then obtain the final lateral acceleration change rate according to the average value of these N - 1 lateral acceleration change rates, where N is an integer greater than or equal to 3.

[0080] Steps for determining a curve coefficient based on the yaw rate of a current vehicle include: collecting the yaw rate of the current vehicle; obtaining a yaw rate change rate based on the yaw rate; obtaining a preset curve recognition threshold, and determining whether the product of the yaw rate and the yaw rate change rate is greater than the curve recognition threshold; if so, determining that the current vehicle is in a state of entering the current curve, and the curve coefficient of the current curve is a first coefficient; if not, determining that the current vehicle is in a state of exiting the current curve, and the curve coefficient of the current curve is a second coefficient. Among them, the yaw rate is used to indicate the angular velocity of the vehicle rotating around the Z-axis, and the Z-axis is used to indicate the axis perpendicular to the ground; the yaw rate can also be collected by setting a speed sensor on the current vehicle, and the speed sensor is used for collection; after the speed sensor collects at least two yaw rates, the yaw rates are transmitted to a vehicle controller, and the vehicle controller obtains the yaw rate change rate according to the ratio of the change amount between the two yaw rates to the time taken for this change amount. To make the value of the yaw rate change rate more accurate, the speed sensor can collect M yaw rates, and the vehicle controller can calculate M - 1 yaw rate change rates based on these M yaw rates, and then obtain the final yaw rate change rate according to the average value of these M - 1 yaw rate change rates, where M is an integer greater than or equal to 3.

[0081] It should be noted that in the above methods of determining the cornering coefficient based on lateral acceleration and based on yaw rate, either one can be adopted, and the first coefficient in the first method and the first coefficient in the second method are the same value, and the second coefficient in the first method and the second coefficient in the second method are the same value. The first coefficient is used to indicate that the influence of entering a curve on the requested torque of the whole vehicle or the requested torque at the axle end is relatively large, and the influence of exiting a curve on the requested torque of the whole vehicle or the requested torque at the axle end is relatively small and can be ignored; the second coefficient is used to indicate that the influence of exiting a curve on the requested torque of the whole vehicle or the requested torque at the axle end is relatively large, and the influence of entering a curve on the requested torque of the whole vehicle or the requested torque at the axle end is relatively small and can be ignored. The values of the first coefficient and the second coefficient can be obtained through on-vehicle tests on curves. By way of example, the first coefficient can be set to 1.5 and the second coefficient can be set to -0.5.

[0082] S102: Calculate the acceleration gain based on the cornering coefficient.

[0083] In an implementable manner, the acceleration gain is calculated based on lateral acceleration and yaw rate. Specifically, the step of calculating the acceleration gain based on the cornering coefficient includes: collecting the yaw rate of the current vehicle and the lateral acceleration perpendicular to the driving direction horizontally; obtaining the lateral acceleration change rate according to the lateral acceleration, and obtaining the yaw rate change rate according to the yaw rate; obtaining a preset first weight; obtaining a first gain based on the lateral acceleration change rate, the cornering coefficient, and the first weight; obtaining a second gain based on the yaw rate change rate, the cornering coefficient, and the first weight; calculating the sum of the first gain and the second gain to obtain the acceleration gain.

[0084] It should be noted that the cornering coefficient involved in the step of calculating the acceleration gain is obtained in the step of determining the cornering coefficient described above. If the cornering coefficient is determined to be the first coefficient in the step of determining the cornering coefficient described above, then the cornering coefficient involved in this step of calculating the acceleration gain is the first coefficient; if the cornering coefficient is determined to be the second coefficient in the step of determining the cornering coefficient described above, then the cornering coefficient involved in this step of calculating the acceleration gain is the second coefficient.

[0085] The methods for obtaining the lateral acceleration, lateral acceleration change rate, yaw rate, and yaw rate change rate in this embodiment are similar to the steps of collecting the lateral acceleration and yaw rate described above, obtaining the lateral acceleration change rate according to the lateral acceleration, and obtaining the yaw rate change rate according to the yaw rate. For relevant descriptions, please refer to the foregoing, and details will not be repeated here.

[0086] If the foregoing curve coefficient is determined based on the lateral acceleration, in the step of calculating the acceleration gain, it is only necessary to collect the yaw rate and obtain the yaw rate change rate based on the yaw rate, and there is no need to collect the lateral acceleration again and perform the step of obtaining the lateral acceleration change rate based on the lateral acceleration; if the foregoing curve coefficient is determined based on the yaw rate, in the step of calculating the acceleration gain, it is only necessary to collect the lateral acceleration and obtain the lateral acceleration change rate based on the lateral acceleration, and there is no need to collect the yaw rate again and perform the step of obtaining the yaw rate change rate based on the yaw rate.

[0087] More specifically, the step of obtaining the first gain based on the lateral acceleration change rate, the curve coefficient, and the first weight includes: obtaining the road allowable acceleration; obtaining the maximum allowable longitudinal acceleration in the driving direction according to the lateral acceleration and the road allowable acceleration, where the mathematical expression for obtaining the maximum allowable longitudinal acceleration includes:

[0088]

[0089] a xmax is the maximum allowable longitudinal acceleration, a g is the road allowable acceleration, a y is the lateral acceleration; obtaining the first gain according to the product of the lateral acceleration change rate, the curve coefficient, the maximum allowable longitudinal acceleration, and the first weight.

[0090] Further, the step of obtaining the second gain based on the yaw rate change rate, the curve coefficient, and the first weight includes: obtaining the second gain according to the yaw rate change rate, the curve coefficient, the maximum allowable longitudinal acceleration, and the first weight, where the mathematical expression for obtaining the second gain includes:

[0091]

[0092] a ωgain is the second gain, is the yaw rate change rate, W is the curve coefficient, a xmax is the maximum allowable longitudinal acceleration, and F1 is the first weight.

[0093] S103: When receiving the vehicle request torque or the request torque at the axle end and the current speed parameter is within the preset speed range, allocate the vehicle request torque based on the acceleration gain, or compensate the request torque at the axle end based on the acceleration gain to obtain the final required torque at the axle end, where the axle end includes the front axle and the rear axle.

[0094] Specifically, in an implementable manner, the step of distributing the vehicle's requested torque based on the acceleration gain to obtain the final required torque at the axle end includes: obtaining a preset second weight; obtaining a gain distribution ratio based on the acceleration gain and the second weight; obtaining a torque change amount according to the product of the gain distribution ratio and the vehicle's requested torque; obtaining the final required torque of the front axle according to the difference between the vehicle's requested torque and the torque change amount; and obtaining the final required torque of the rear axle according to the sum of the vehicle's requested torque and the torque change amount.

[0095] In another implementable manner, the step of compensating the requested torque at the axle end based on the acceleration gain to obtain the final required torque at the axle end includes: obtaining the vehicle mass, wheel rolling radius of the current vehicle, and a preset second weight; obtaining a gain distribution ratio based on the acceleration gain and the second weight; obtaining the torque gain at the axle end according to the acceleration gain, the gain distribution ratio, the vehicle mass, and the wheel rolling radius, where the mathematical expression for obtaining the torque gain at the axle end includes:

[0096] T Fgain =a gain *a d *m*r

[0097] T Rgain =a gain *(1 - a gain )*m*r

[0098] T Fgain is the torque gain of the front axle, a gain is the acceleration gain, a d is the gain distribution ratio, m is the vehicle mass, r is the wheel rolling radius, and T Rgain is the torque gain of the rear axle; superimposing the torque gain of the same axle end with the requested torque to obtain the final required torque at the axle end. That is, superimposing the torque gain of the front axle with the requested torque of the front axle to obtain the final required torque of the front axle, and superimposing the torque gain of the rear axle with the requested torque of the rear axle to obtain the final required torque of the rear axle.

[0099] In the above steps of distributing the vehicle's requested torque based on the acceleration gain and compensating the requested torque at the axle end based on the acceleration gain, the step of obtaining the gain distribution ratio based on the acceleration gain and the second weight includes: obtaining the gain distribution ratio according to the lateral acceleration change rate, the cornering coefficient, the yaw rate change rate, the acceleration gain, and the second weight, where the mathematical expression for obtaining the gain distribution ratio includes:

[0100]

[0101] a d is the gain allocation ratio, is the lateral acceleration change rate, W is the cornering coefficient, F2 is the second weight, a gain is the acceleration gain, is the yaw rate change rate.

[0102] In an implementable manner, the vehicle's requested torque can be obtained according to the following steps: Collect the current driving speed; Obtain the current throttle depth, and based on the current driving speed and the current throttle depth, obtain the vehicle's original required torque; Based on the current driving speed and the vehicle's original required torque, obtain the torque gradient; Based on the sum of the vehicle's original required torque and the torque gradient, obtain the vehicle's requested torque. Among them, the current driving speed can be collected by setting a speed sensor on the vehicle, and the current throttle depth is determined by the depth at which the driver depresses the accelerator pedal.

[0103] Among them, the step of obtaining the vehicle's original required torque based on the current driving speed and the current throttle depth refers to: Obtain a preset first mapping table, and perform a lookup in the first mapping table based on the current driving speed and the current throttle depth to obtain the vehicle's original required torque, where the first mapping table is used to indicate the mapping relationship between the current driving speed, the current throttle depth, and the vehicle's original required torque. The step of obtaining the torque gradient based on the current driving speed and the vehicle's original required torque refers to: Obtain a preset second mapping table, and perform a lookup in the second mapping table based on the current driving speed and the vehicle's original required torque to obtain the torque gradient, where the second mapping table is used to indicate the mapping relationship between the current driving speed, the vehicle's original required torque, and the torque gradient.

[0104] In other embodiments, the vehicle's requested torque can also be filtered. Specifically, obtain a preset filter coefficient and the filtered output value of the historical vehicle's requested torque, and according to the mathematical expression y (t) = K * T V +(1 - k) * y (t-1) , obtain the filtered output value of the vehicle's requested torque at the current moment, where y (t) is the filtered output value of the vehicle's requested torque at the current moment, K is the filter coefficient, T V is the vehicle's requested torque at the current moment, y (t-1)is the filtered output value of the historical vehicle request torque, where the historical vehicle request torque refers to the vehicle request torque received at the previous moment adjacent to the current moment. Among them, the filtering coefficient can be obtained according to the following steps: obtaining a preset third mapping table, obtaining the torque difference between the original vehicle demand torque and the vehicle request torque, and looking up in the third mapping table based on the torque difference and the current driving speed to obtain the filtering coefficient, where the third mapping table is used to indicate the mapping relationship between the torque difference, the current driving speed, and the filtering coefficient.

[0105] In an implementable manner, the current speed parameter includes at least one of a yaw rate, a yaw rate change rate, and a lateral acceleration change rate perpendicular to the driving direction horizontally; the speed interval includes at least one of a first interval, a second interval, and a third interval; the first interval corresponds to the yaw rate, the second interval corresponds to the yaw rate change rate, and the third interval corresponds to the lateral acceleration change rate.

[0106] It should be noted that the first interval, the second interval, and the third interval are speed intervals for determining whether to perform the step of allocating the vehicle request torque based on the acceleration gain or compensating the request torque at the axle end.

[0107] Specifically, the first interval is used to determine whether to activate the step of allocating the vehicle request torque or compensating the request torque at the axle end according to the yaw rate. Exemplarily, the first interval can be (0.6, 0.8]. When the yaw rate is greater than 0.6 and less than or equal to 0.8, the step of allocating the vehicle request torque or compensating the request torque at the axle end is activated; the second interval is used to determine whether to activate the step of allocating the vehicle request torque or compensating the request torque at the axle end according to the yaw rate change rate. Exemplarily, the second interval can be (0.1, 1]. When the yaw rate change rate is greater than 0.1 and less than or equal to 1, the step of allocating the vehicle request torque or compensating the request torque at the axle end is activated; the third interval is used to determine whether to activate the step of allocating the vehicle request torque or compensating the request torque at the axle end according to the lateral acceleration change rate. Exemplarily, the third interval can be (1.5, 1.7]. When the lateral acceleration change rate is greater than 1.5 and less than or equal to 1.7, the step of allocating the vehicle request torque or compensating the request torque at the axle end is activated.

[0108] When receiving the requested torque of the whole vehicle or the requested torque at the axle end, when any of the above conditions is met, the steps of allocating the requested torque of the whole vehicle or compensating the requested torque at the axle end can be activated, and it is not necessary to meet all of them. And in some preferred embodiments, it is possible to determine whether to activate the steps of allocating the requested torque of the whole vehicle or compensating the requested torque at the axle end in the order of first determining whether the yaw rate is within the first interval, then determining whether the lateral acceleration change rate is within the third interval, and finally determining whether the yaw rate change rate is within the second interval.

[0109] S104: Control the drive motor to respond to the final required torque at the axle end.

[0110] It should be noted that the drive motor can be one or two; in the case where the vehicle includes one drive motor, the drive motor simultaneously drives the operation of the front axle and the rear axle, and in the case where the vehicle includes two drive motors, the two drive motors respectively control the operation of the front axle and the rear axle.

[0111] In the above vehicle control method applied to a curve, by determining the real-time curve coefficient, then calculating the acceleration gain based on the curve coefficient, and then when receiving the requested torque of the whole vehicle or the requested torque at the axle end, allocating the requested torque of the whole vehicle or compensating the requested torque at the axle end based on the acceleration gain to obtain the final required torque at the axle end. The above method realizes the real-time allocation of the requested torque of the whole vehicle according to the actual situation of the curve and the driver's operation intention, or performs positive compensation or negative compensation on the requested torque at the axle end without affecting the original requested torque at the axle end, thereby realizing the change of the vehicle's steering characteristics, improving the vehicle's entry and exit speed of the curve, stabilizing the lateral acceleration, reducing the fluctuation of the yaw rate, and effectively improving the stability and power performance of the vehicle when turning. Therefore, compared with the prior art, the above method improves the driving efficiency of the vehicle on the curve.

[0112] It should be understood that although Figure 1 the steps in the flowchart of Figure 1 are shown in sequence according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover,

[0113] In one embodiment, a vehicle control device applied to a bend is provided. The device includes a vehicle controller. Wherein, the vehicle controller is configured to:

[0114] Determine the bend coefficient of the current bend

[0115] Calculate the acceleration gain based on the bend coefficient;

[0116] When receiving the vehicle request torque or the request torque at the axle end, and the current speed parameter is within a preset speed range, allocate the vehicle request torque based on the acceleration gain, or compensate the request torque at the axle end based on the acceleration gain to obtain the final required torque at the axle end. Wherein, the axle end includes a front axle and a rear axle;

[0117] Control the drive motor to respond to the final required torque at the axle end.

[0118] Specifically, referring to Figure 2 , the device further includes a speed sensor. Wherein, the speed sensor is electrically connected to the vehicle controller and is used to collect the lateral acceleration of the current vehicle perpendicular to the driving direction; the vehicle controller is further configured to obtain the lateral acceleration change rate according to the lateral acceleration; obtain a preset bend recognition threshold, and judge whether the product of the lateral acceleration and the lateral acceleration change rate is greater than the bend recognition threshold; if so, determine that the current vehicle is in a state of entering the current bend, and the bend coefficient of the current bend is the first coefficient; if not, determine that the current vehicle is in a state of exiting the current bend, and the bend coefficient of the current bend is the second coefficient.

[0119] Specifically, the speed sensor is further used to collect the yaw angular velocity of the current vehicle; the vehicle controller is further configured to obtain the yaw angular velocity change rate according to the yaw angular velocity; obtain a preset bend recognition threshold, and judge whether the product of the yaw angular velocity and the yaw angular velocity change rate is greater than the bend recognition threshold; if so, determine that the current vehicle is in a state of entering the current bend, and the bend coefficient of the current bend is the first coefficient; if not, determine that the current vehicle is in a state of exiting the current bend, and the bend coefficient of the current bend is the second coefficient.

[0120] Specifically, the speed sensor is further configured to collect the yaw rate of the current vehicle and the lateral acceleration perpendicular to the driving direction in the horizontal plane; the vehicle controller is further configured to obtain the lateral acceleration change rate according to the lateral acceleration, obtain the yaw rate change rate according to the yaw rate; obtain a preset first weight; based on the lateral acceleration change rate, the curve coefficient, and the first weight, obtain a first gain; based on the yaw rate change rate, the curve coefficient, and the first weight, obtain a second gain; calculate the sum of the first gain and the second gain to obtain the acceleration gain.

[0121] Specifically, the step in which the vehicle controller obtains the first gain based on the lateral acceleration change rate, the curve coefficient, and the first weight includes: obtaining the road allowable acceleration; according to the lateral acceleration and the road allowable acceleration, obtaining the maximum allowable longitudinal acceleration in the driving direction, where the mathematical expression for obtaining the maximum allowable longitudinal acceleration includes:

[0122]

[0123] a xmax is the maximum allowable longitudinal acceleration, a g is the road allowable acceleration, a y is the lateral acceleration; according to the product of the lateral acceleration change rate, the curve coefficient, the maximum allowable longitudinal acceleration, and the first weight, obtain the first gain.

[0124] Specifically, the step in which the vehicle controller obtains the second gain based on the yaw rate change rate, the curve coefficient, and the first weight includes: according to the yaw rate change rate, the curve coefficient, the maximum allowable longitudinal acceleration, and the first weight, obtain the second gain, where the mathematical expression for obtaining the second gain includes:

[0125]

[0126] a ωgain is the second gain, is the yaw rate change rate, W is the curve coefficient, a xmax is the maximum allowable longitudinal acceleration, F1 is the first weight.

[0127] Specifically, the step of the vehicle controller distributing the vehicle request torque based on the acceleration gain to obtain the final required torque at the axle end includes: obtaining a preset second weight; obtaining a gain distribution ratio based on the acceleration gain and the second weight; obtaining a torque change amount according to the product of the gain distribution ratio and the vehicle request torque; obtaining the final required torque of the front axle according to the difference between the vehicle request torque and the torque change amount; and obtaining the final required torque of the rear axle according to the sum of the vehicle request torque and the torque change amount.

[0128] Specifically, the step of the vehicle controller compensating the request torque at the axle end based on the acceleration gain to obtain the final required torque at the axle end includes: obtaining the vehicle mass, wheel rolling radius of the current vehicle, and a preset second weight; obtaining a gain distribution ratio based on the acceleration gain and the second weight; obtaining the torque gain at the axle end according to the acceleration gain, the gain distribution ratio, the vehicle mass, and the wheel rolling radius, where the mathematical expression for obtaining the torque gain at the axle end includes:

[0129] T Fgain =a gain *a d *m*r

[0130] T Rgain =a gain *(1 - a gain )*m*r

[0131] T Fgain is the torque gain of the front axle, a gain is the acceleration gain, a d is the gain distribution ratio, m is the vehicle mass, r is the wheel rolling radius, T Rgain is the torque gain of the rear axle; superimposing the torque gain and the request torque of the same axle end to obtain the final required torque at the axle end.

[0132] Specifically, the step of the vehicle controller obtaining a gain distribution ratio based on the acceleration gain and the second weight includes: obtaining a gain distribution ratio according to the lateral acceleration change rate, the cornering coefficient, the yaw rate change rate, the acceleration gain, and the second weight, where the mathematical expression for obtaining the gain distribution ratio includes:

[0133]

[0134] ad is the gain distribution ratio, is the lateral acceleration change rate, W is the cornering coefficient, F2 is the second weight, a gainwhere \(K_a\) is the acceleration gain and \(\omega\) is the yaw rate of change.

[0135] Specifically, before the step of receiving the vehicle's requested torque, the speed sensor is further configured to collect the current driving speed; the vehicle controller is further configured to obtain the current throttle depth, and based on the current driving speed and the current throttle depth, obtain the original vehicle demand torque; based on the current driving speed and the original vehicle demand torque, obtain the torque gradient; obtain the historical vehicle demand torque, and based on the original vehicle demand torque and the historical vehicle demand torque, obtain the torque gradient change factor; and based on the original vehicle demand torque, the torque gradient, and the torque gradient change factor, obtain the vehicle's requested torque.

[0136] Specifically, the current speed parameter includes at least one of the yaw rate, the yaw rate of change, and the lateral acceleration rate of change perpendicular to the driving direction in the horizontal plane; the speed interval includes at least one of the first interval, the second interval, and the third interval; the first interval corresponds to the yaw rate, the second interval corresponds to the yaw rate of change, and the third interval corresponds to the lateral acceleration rate of change.

[0137] For the specific limitations of the vehicle control device applied to a curve, reference may be made to the limitations of the vehicle control method applied to a curve in the above text, which will not be elaborated here. Each component in the above vehicle control device applied to a curve can be implemented in whole or in part by software, hardware, and their combination. The above components can be embedded in the processor of the computer device in hardware form or be independent of it, or be stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to each of the above components.

[0138] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the various embodiments provided in the present application can include non-volatile and / or volatile memories. Non-volatile memories can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memories can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0139] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0140] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A vehicle control method applied to a bend, characterized in that, The method includes: Determining the curve coefficient of the current curve; Calculating the acceleration gain based on the curve coefficient; When receiving the vehicle's requested torque or the requested torque at the axle end, and the current speed parameter is within a preset speed range, distributing the vehicle's requested torque based on the acceleration gain, or performing positive or negative compensation on the requested torque at the axle end based on the acceleration gain, to obtain the final required torque at the axle end, where the axle end includes the front axle and the rear axle; Controlling the drive motor to respond to the final required torque at the axle end.

2. The vehicle control method applied to a bend according to claim 1, wherein The step of determining the curve coefficient of the current curve includes: Collecting the lateral acceleration of the current vehicle perpendicular to the driving direction; Obtaining the lateral acceleration change rate according to the lateral acceleration; Obtaining a preset curve recognition threshold, and determining whether the product of the lateral acceleration and the lateral acceleration change rate is greater than the curve recognition threshold; If so, determining that the current vehicle is in the state of entering the current curve, and the curve coefficient of the current curve is the first coefficient; If not, determining that the current vehicle is in the state of exiting the current curve, and the curve coefficient of the current curve is the second coefficient.

3. The vehicle control method applied to a bend according to claim 1, characterized in that, The step of determining the curve coefficient of the current curve includes: Collecting the yaw angular velocity of the current vehicle; Obtaining the yaw angular velocity change rate according to the yaw angular velocity; Obtaining a preset curve recognition threshold, and determining whether the product of the yaw angular velocity and the yaw angular velocity change rate is greater than the curve recognition threshold; If so, determining that the current vehicle is in the state of entering the current curve, and the curve coefficient of the current curve is the first coefficient; If not, determining that the current vehicle is in the state of exiting the current curve, and the curve coefficient of the current curve is the second coefficient.

4. The vehicle control method applied to a curve according to claim 1, wherein, The step of calculating the acceleration gain based on the curve coefficient includes: Collecting the yaw angular velocity of the current vehicle and the lateral acceleration perpendicular to the driving direction; Obtaining the lateral acceleration change rate according to the lateral acceleration, and obtaining the yaw angular velocity change rate according to the yaw angular velocity; Obtaining a preset first weight; Obtaining a first gain based on the lateral acceleration change rate, the curve coefficient, and the first weight; Obtaining a second gain based on the yaw angular velocity change rate, the curve coefficient, and the first weight; Calculating the sum of the first gain and the second gain to obtain the acceleration gain.

5. The vehicle control method applied to a bend according to claim 4, characterized in that, The step of obtaining a first gain based on the lateral acceleration change rate, the curve coefficient, and the first weight includes: Obtaining the road allowable acceleration; Obtaining the maximum allowable longitudinal acceleration in the driving direction according to the lateral acceleration and the road allowable acceleration, where the mathematical expression for obtaining the maximum allowable longitudinal acceleration includes: a xmax is the maximum allowable longitudinal acceleration, a g is the road allowable acceleration, a y is the lateral acceleration; Obtaining the first gain according to the product of the lateral acceleration change rate, the curve coefficient, the maximum allowable longitudinal acceleration, and the first weight.

6. The vehicle control method applied to a curve according to claim 5, characterized in that The step of obtaining a second gain based on the yaw angular velocity change rate, the curve coefficient, and the first weight includes: Obtain the second gain according to the yaw rate change rate, the curve coefficient, the maximum allowable longitudinal acceleration, and the first weight, wherein the mathematical expression for obtaining the second gain includes: a ωgain is the second gain, is the yaw rate of change, W is the curve coefficient, a xmax is the maximum allowable longitudinal acceleration, and F1 is the first weight.

7. The vehicle control method applied to a curve according to claim 4, characterized in that, The step of distributing the vehicle's requested torque based on the acceleration gain to obtain the final required torque at the axle end includes: Obtain a preset second weight; Based on the acceleration gain and the second weight, obtain a gain distribution ratio; Obtain a torque change amount according to the product of the gain distribution ratio and the vehicle's requested torque; Obtain the final required torque of the front axle according to the difference between the vehicle's requested torque and the torque change amount; Obtain the final required torque of the rear axle according to the sum of the vehicle's requested torque and the torque change amount.

8. The vehicle control method applied to a curve according to claim 4, wherein The step of compensating the requested torque at the axle end based on the acceleration gain to obtain the final required torque at the axle end includes: Obtain the vehicle mass of the current vehicle, the wheel rolling radius, and a preset second weight; Based on the acceleration gain and the second weight, obtain a gain distribution ratio; Obtain the torque gain at the axle end according to the acceleration gain, the gain distribution ratio, the vehicle mass, and the wheel rolling radius, wherein the mathematical expression for obtaining the torque gain at the axle end includes: T Fgain = a gain * a d * m * r T Rgain = a gain *(1 - a gain )*m*r T Fgain is the torque gain of the front axle, a gain is the acceleration gain, a d is the gain distribution ratio, m is the vehicle mass, r is the wheel rolling radius, T Rgain is the torque gain of the rear axle; Superimpose the torque gain of the same axle end and the requested torque to obtain the final required torque at the axle end.

9. The vehicle control method applied to a curve according to claim 7 or 8, characterized in that, The step of obtaining the gain distribution ratio based on the acceleration gain and the second weight includes: Obtain the gain distribution ratio according to the lateral acceleration change rate, the curve coefficient, the yaw rate change rate, the acceleration gain, and the second weight, wherein the mathematical expression for obtaining the gain distribution ratio includes: a d is the gain allocation ratio, is the lateral acceleration change rate, W is the cornering coefficient, F2 is the second weight, a gain is the acceleration gain, is the yaw rate change rate.

10. The vehicle control method applied to a bend according to claim 1, characterized in that, Before the step of receiving the vehicle's requested torque, it includes: Collect the current driving speed; Obtain the current throttle depth, and according to the current driving speed and the current throttle depth, obtain the original required torque of the vehicle; Obtain the torque gradient according to the current driving speed and the original required torque of the vehicle; Obtain the vehicle's requested torque according to the sum of the original required torque of the vehicle and the torque gradient.

11. The vehicle control method applied to a bend according to claim 1, characterized in that, The current speed parameter includes at least one of the yaw rate, the yaw rate change rate, and the lateral acceleration change rate perpendicular to the driving direction in the horizontal plane; the speed interval includes at least one of the first interval, the second interval, and the third interval; the first interval corresponds to the yaw rate, the second interval corresponds to the yaw rate change rate, and the third interval corresponds to the lateral acceleration change rate.

12. An automobile control device applied to a curve, characterized in that, The device includes a vehicle controller, wherein the vehicle controller is used for: Determine the curve coefficient of the current curve Calculate the acceleration gain based on the curve coefficient; When receiving the vehicle's requested torque or the requested torque at the axle end, and the current speed parameter is within the preset speed interval, distribute the vehicle's requested torque based on the acceleration gain, or perform positive or negative compensation on the requested torque at the axle end based on the acceleration gain, to obtain the final required torque at the axle end, wherein the axle end includes the front axle and the rear axle; Control the drive motor in response to the final required torque at the shaft end.

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