Vehicle control method, device, storage medium and vehicle

Abstract

The present disclosure relates to a vehicle control method, device, storage medium and vehicle. The method comprises: acquiring a vehicle speed and a hand torque received by a steering wheel; acquiring a target assist characteristic curve corresponding to the vehicle speed from a plurality of assist characteristic curves calibrated in advance, a line segment corresponding to a first hand torque interval in the assist characteristic curve is a straight line segment, a line segment corresponding to a second hand torque interval in the assist characteristic curve is a curve segment with an opening upward, a maximum value of the first hand torque interval is equal to or less than a minimum value of the second hand torque interval, and the assist characteristic curve represents a mapping relationship between a hand torque and an assist torque; determining a target assist torque according to the hand torque and the target assist characteristic curve; and adjusting an assist torque of the steering wheel to the target assist torque. The present disclosure can better coordinate steering lightness at low speed and road feeling at high speed.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of vehicles, in particular to a vehicle control method and device, a storage medium and a vehicle. BACKGROUND

[0002] An electric power steering system (EPS) is a power steering system that directly relies on an electric motor to provide auxiliary torque, mainly composed of a torque sensor, a vehicle speed sensor, an electric motor, a speed reduction mechanism and an electronic control unit (ECU).

[0003] The torque sensor is connected with a steering shaft, when the steering shaft rotates, the torque sensor converts the relative rotation angle displacement generated by the input shaft and the output shaft under the action of the torsion bar into an electrical signal and transmits it to the ECU, and the ECU determines the rotation direction of the electric motor and the size of the assist current according to the signals of the vehicle speed sensor and the torque sensor, to complete real-time control of the power steering.

[0004] In the electric power steering system, the assist characteristic curve is the key to the execution of electric power assistance by the vehicle, and the current assist characteristic curve is relatively single and cannot meet the needs of users. SUMMARY

[0005] To overcome the problems in the related art, the present disclosure provides a vehicle control method and device, a storage medium and a vehicle.

[0006] According to a first aspect of an embodiment of the present disclosure, a vehicle control method is provided, comprising:

[0007] obtaining a vehicle speed of the vehicle and a hand torque received by a steering wheel;

[0008] obtaining a target assist characteristic curve corresponding to the vehicle speed from a plurality of assist characteristic curves pre-marked, a line segment corresponding to a first hand torque interval in the assist characteristic curve being a straight line segment, a line segment corresponding to a second hand torque interval in the assist characteristic curve being a curve segment with an opening upward, a maximum value of the first hand torque interval being equal to or less than a minimum value of the second hand torque interval, the assist characteristic curve representing a mapping relationship between the hand torque and the assist torque;

[0009] determining a target assist torque according to the hand torque and the target assist characteristic curve;

[0010] adjusting the assist torque of the steering wheel to the target assist torque.

[0011] Optionally, the method further comprises:

[0012] For each of a plurality of preset vehicle speeds, a plurality of hand torques measured at a plurality of steering angles of the vehicle at the vehicle speed are obtained, the plurality of hand torques corresponding to the plurality of steering angles one by one;

[0013] The first hand torque interval is determined according to hand torques corresponding to steering angles less than a specified steering angle in the plurality of hand torques;

[0014] The second hand torque interval is determined according to hand torques corresponding to steering angles greater than or equal to the specified steering angle in the plurality of hand torques.

[0015] Optionally, the method further comprises:

[0016] For each of a plurality of preset vehicle speeds, a maximum assist torque and a maximum hand torque of the vehicle at the vehicle speed are obtained;

[0017] A slope of the straight line segment is determined according to the maximum assist torque and the maximum hand torque;

[0018] An expression of the straight line segment is determined based on the slope of the straight line segment and minimum and maximum values of the first hand torque interval.

[0019] Optionally, the determining the slope of the straight line segment according to the maximum assist torque and the maximum hand torque comprises:

[0020] A reference slope is calculated by taking a quotient of the maximum assist torque and the maximum hand torque;

[0021] The reference slope is corrected by a preset correction value to obtain the slope of the straight line segment, the slope of the straight line segment being less than the reference slope.

[0022] Optionally, the correcting the reference slope by the preset correction value to obtain the slope of the straight line segment comprises:

[0023] A corrected maximum hand torque is calculated by taking a sum of the preset correction value and the maximum hand torque;

[0024] The slope of the straight line segment is calculated by taking a quotient of the maximum assist torque and the corrected maximum hand torque.

[0025] Optionally, the method further comprises:

[0026] A difference between a maximum value of the second hand torque interval and a minimum value of the first hand torque interval is calculated, and a half of the difference is determined as a target abscissa;

[0027] determine a reference longitudinal coordinate according to the target horizontal coordinate, a maximum value of the second hand torque interval, a minimum value of the first hand torque interval, and a maximum boost torque of the vehicle;

[0028] correct the reference longitudinal coordinate to obtain a target longitudinal coordinate, the target longitudinal coordinate having a value less than the reference longitudinal coordinate;

[0029] determine a target coordinate according to the target horizontal coordinate and the target longitudinal coordinate;

[0030] determine an expression of the curve segment according to the maximum boost torque, the maximum hand torque, and the target coordinate.

[0031] Optionally, the determining of the expression of the curve segment according to the maximum boost torque, the maximum hand torque, and the target coordinate comprises:

[0032] take the maximum boost torque as a first longitudinal coordinate and the maximum hand torque as a first horizontal coordinate to obtain a first coordinate;

[0033] take the minimum value of the first hand torque interval as a second horizontal coordinate and 0 as a second longitudinal coordinate to obtain a second coordinate;

[0034] input the first coordinate, the second coordinate, and the target coordinate into a preset curve formula to calculate a parameter of the curve formula;

[0035] determine the expression of the curve segment based on the parameter and the preset curve formula.

[0036] According to a second aspect of the embodiments of the present disclosure, a vehicle control device is provided, which comprises:

[0037] an information acquisition module configured to acquire a vehicle speed of the vehicle and a hand torque received by a steering wheel;

[0038] a target boost characteristic curve determination module configured to acquire a target boost characteristic curve corresponding to the vehicle speed from a plurality of boost characteristic curves pre-calibrated, a line segment corresponding to a first hand torque interval in the boost characteristic curve being a straight line segment, a line segment corresponding to a second hand torque interval in the boost characteristic curve being a curve segment with an open upward, a maximum value of the first hand torque interval being equal to or less than a minimum value of the second hand torque interval, the boost characteristic curve representing a mapping relationship between a hand torque and a boost torque;

[0039] a target boost torque determination module configured to determine a target boost torque according to the hand torque and the target boost characteristic curve;

[0040] a control module configured to adjust a boost torque of the steering wheel to the target boost torque.

[0041] According to a third aspect of the embodiments of the present disclosure, a non-transitory computer readable storage medium is provided, having stored thereon a computer program which, when executed by a processor, implements the steps of the method of the first aspect.

[0042] According to a fourth aspect of the embodiments of the present disclosure, a vehicle is provided, comprising:

[0043] a memory having stored thereon a computer program;

[0044] a processor configured to execute the computer program in the memory to implement the steps of the method of the first aspect.

[0045] The technical solutions provided by the embodiments of the present disclosure can have the following beneficial effects: by obtaining the vehicle speed and the hand torque received by the steering wheel, a target assist characteristic curve corresponding to the vehicle speed is obtained from a plurality of assist characteristic curves calibrated in advance, a line segment corresponding to a first hand torque interval in the assist characteristic curve is a straight line segment, a line segment corresponding to a second hand torque interval in the assist characteristic curve is a curve segment with an upward opening, the maximum value of the first hand torque interval is equal to or less than the minimum value of the second hand torque interval, and the assist characteristic curve represents a mapping relationship between the hand torque and the assist torque; a target assist torque is determined according to the hand torque and the target assist characteristic curve; and the assist torque of the steering wheel is adjusted to the target assist torque. That is, according to the assist characteristic curve, the vehicle can adopt a straight line type assist curve combined with a curve type assist curve for segmented control, when the vehicle detects that the current hand torque is in the first hand torque interval with a relatively small hand torque, it indicates that small angle steering is performed, at this time, the straight line type assist characteristic curve is adopted, control is simple, the data amount is small, and real-time performance and followability are good; when the vehicle detects that the current hand torque is in the second hand torque interval with a relatively large hand torque, it indicates that large angle steering is performed, at this time, the curve type assist characteristic curve with an upward opening (i.e., a curve with a larger slope) is adopted, so that the electric assist can be increased more quickly, and better road feeling can be ensured during high speed driving.

[0046] Other features and advantages of the present disclosure will be described in detail in the following detailed description section. BRIEF DESCRIPTION OF DRAWINGS

[0047] The accompanying drawings are included to provide a further understanding of the present disclosure and constitute a part of the specification, and are used to explain the present disclosure together with the following detailed description, but do not limit the present disclosure. In the drawings:

[0048] Figure 1 is a flowchart of a vehicle control method according to an exemplary embodiment.

[0049] Figure 2is according to Figure 1 A schematic diagram of a segmented control EPS assist characteristic curve is shown in accordance with an embodiment.

[0050] Figure 3 is according to Figure 1 A schematic diagram of a target assist characteristic curve at a vehicle speed of 40 Km / h is shown in accordance with an embodiment.

[0051] Figure 4 A flowchart of a vehicle control method is shown in accordance with another exemplary embodiment.

[0052] Figure 5 is according to Figure 4 A schematic diagram of a correction to a straight line slope is shown in accordance with an embodiment.

[0053] Figure 6 is according to Figure 4 A schematic diagram of a correction to a reference ordinate is shown in accordance with an embodiment.

[0054] Figure 7 is according to Figure 4 An implementation schematic diagram of a control method is shown in accordance with an embodiment.

[0055] Figure 8 A block diagram of a vehicle control apparatus is shown in accordance with an exemplary embodiment.

[0056] Figure 9 A functional block diagram schematic of a vehicle is shown in accordance with an exemplary embodiment. DETAILED DESCRIPTION

[0057] The specific embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely intended to illustrate and explain the present disclosure, and are not intended to limit the present disclosure.

[0058] It should be noted that all actions of obtaining signals, information or data in the present disclosure are carried out in compliance with the corresponding data protection regulations and policies of the country where the device is located, and with the authorization of the corresponding device owner.

[0059] In the increasingly competitive automobile market, automobile products equipped with electric power steering systems (EPS) have more market competitiveness, are the inevitable choice of automobile unmanned and intelligent, and are the inevitable trend of the development of automobile steering systems. The assist control mode is the most basic control method of EPS. The main function of this mode is to enable the driver to obtain good road feel and hand feel. A reasonable assist characteristic has an important influence on the driving convenience, road feel, safety and return characteristics of the vehicle.

[0060] In the assist control mode, the design of the assist characteristic curve is the main design goal of the control strategy. First, a specific ideal characteristic curve is obtained through theoretical analysis, and then the ECU determines the current of the assist motor according to the vehicle speed, torque and other sensor signals through a certain algorithm to obtain the appropriate assist torque, so as to track a certain ideal assist characteristic curve. Therefore, the characteristic curve of the EPS can be adjusted through software. The designed assist characteristic curve should be able to well coordinate the relationship between steering lightness and road feeling, and ensure that the steering characteristics provided to the driver are as consistent as possible as manual steering and without sudden changes. Steering lightness is a basic requirement of the steering system. After meeting this basic condition, attention must also be paid to the assist force provided, which cannot be too large, otherwise it will lead to too light steering and the driver will lose the information from the road, that is, the road feeling, which will make the driver unable to judge the change of the vehicle running state.

[0061] Therefore, in fact, the lightness and the road feeling of driving are a pair of contradictions, and both the above two needs must be considered when designing the assist characteristic curve to coordinate the relationship between the two.

[0062] However, in the related art, the design of the assist characteristic curve is relatively single, and the above two needs cannot be considered at the same time, thereby leading to poor user experience.

[0063] In view of the above problems, the embodiment provides a vehicle control method, device, storage medium and vehicle, which can better coordinate the steering lightness at low speed and the road feeling at high speed.

[0064] Figure 1 is a flowchart of a vehicle control method according to an exemplary embodiment, as shown in Figure 1 The method is used in a vehicle, specifically can be applied to the ECU in the vehicle, and the vehicle control method can include the following steps:

[0065] In step S11, the vehicle speed of the vehicle and the hand torque received by the steering wheel are obtained.

[0066] In some embodiments, the vehicle can obtain the current vehicle speed through the CAN network of the whole vehicle and obtain the current hand torque collected from the TAS sensor through the ECU.

[0067] In step S12, a target assist characteristic curve corresponding to the vehicle speed is obtained from a plurality of assist characteristic curves pre-marked, a line segment corresponding to a first hand torque interval in the assist characteristic curve is a straight line segment, a line segment corresponding to a second hand torque interval in the assist characteristic curve is a curve segment with an open upward, the maximum value of the first hand torque interval is equal to or less than the minimum value of the second hand torque interval, and the assist characteristic curve represents the mapping relationship between the hand torque and the assist torque.

[0068] In some embodiments, a plurality of pre-calibrated assist characteristics are pre-stored in the vehicle, for example, the plurality of pre-calibrated assist characteristics (i.e. the piecewise controlled EPS assist characteristics) can be as shown in Figure 2 . In which, in Figure 2 , the horizontal axis of the coordinate system in which the plurality of assist characteristics are located represents the steering torque T d , i.e. the steering torque exerted by the driver on the steering wheel; the vertical axis represents the assist torque T, i.e. the assist torque provided by the motor. Each of the plurality of assist characteristics corresponds to a vehicle speed, that is, the vehicle uses different assist characteristics at different vehicle speeds.

[0069] As an example, for example, the current vehicle speed is 40 Km / h, the assist characteristic corresponding to V = 40 Km / h can be selected from the plurality of pre-set assist characteristics as the target assist characteristic, in which the target assist characteristic can be as shown in Figure 3 . The target assist characteristic generally includes a straight line segment corresponding to the first steering torque interval (T d0 to T dk ), a curve segment corresponding to the second steering torque interval (T dk to T dmax ), etc. According to Figure 3 , it can be seen that the slope of the curve segment is larger than the slope of the straight line segment, and the slope becomes larger and larger as the steering torque gradually increases.

[0070] It can also be understood that due to the inherent damping, friction and moment of inertia of the steering system and the random disturbance information of the road surface transmitted to the steering wheel, the steering wheel will produce slight vibration, which will affect the driving comfort, therefore, the starting point of the assist characteristic is not from the origin, usually a dead zone threshold T d0 is set, so that the assist characteristic starts from the coordinate (T d0 , 0). That is, when the steering torque is between (0, 0) and (T d0 , 0), the vehicle cannot respond to the steering torque.

[0071] It can be understood that the upward-opening curve can be an upward-opening arc, and the slope on the curve gradually increases as the horizontal coordinate (steering torque) gradually increases.

[0072] It can be understood that the greater the hand torque applied by the user to the steering wheel, the greater the steering angle of the vehicle. Therefore, by using the target assist characteristic curve, the steering angle can be controlled. When small angle steering is performed, a linear assist characteristic curve is used, which is simple to control, has small data volume, and has good real-time performance and followability. When large angle steering is performed, a curve assist characteristic curve with a greater slope is used, so that the electric assist can be increased more quickly, thereby ensuring better road feel during high-speed driving.

[0073] In step S13, a target assist torque is determined according to the hand torque and the target assist characteristic curve.

[0074] In some embodiments, since the target assist characteristic curve represents the mapping relationship between the hand torque and the assist torque at the current vehicle speed, the corresponding assist torque can be determined from the target assist characteristic curve according to the hand torque as the target assist torque.

[0075] In step S14, the assist torque of the steering wheel is adjusted to the target assist torque.

[0076] In some embodiments, the ECU of the vehicle can control the vehicle to adjust the assist torque of the steering wheel to the target assist torque.

[0077] It can be seen that in the present embodiment, the vehicle speed and the hand torque received by the steering wheel are obtained, a target assist characteristic curve corresponding to the vehicle speed is obtained from the pre-calibrated plurality of assist characteristic curves, the line segment corresponding to the first hand torque interval in the assist characteristic curve is a straight line segment, the line segment corresponding to the second hand torque interval in the assist characteristic curve is a curve segment with an upward opening, the maximum value of the first hand torque interval is equal to or less than the minimum value of the second hand torque interval, and the assist characteristic curve represents the mapping relationship between the hand torque and the assist torque. A target assist torque is determined according to the hand torque and the target assist characteristic curve. The assist torque of the steering wheel is adjusted to the target assist torque. That is, according to the assist characteristic curve, the vehicle can use a linear assist curve combined with a curve assist curve for segmented control. When the vehicle detects that the current hand torque is in the first hand torque interval with a relatively small hand torque, it means that small angle steering is performed, and a linear assist characteristic curve is used at this time, which is simple to control, has small data volume, and has good real-time performance and followability. When the vehicle detects that the current hand torque is in the second hand torque interval with a relatively large hand torque, it means that large angle steering is performed, and a curve assist characteristic curve with an upward opening (i.e., a curve with a greater slope) is used at this time, so that the electric assist can be increased more quickly, thereby ensuring better road feel during high-speed driving.

[0078] Figure 4 is a flowchart of a vehicle control method according to another exemplary embodiment, as Figure 4As shown, the method is used in a vehicle, and can be applied to an ECU in the vehicle. The vehicle control method can include the following steps:

[0079] In step S21, the vehicle speed of the vehicle and the steering torque received by the steering wheel are obtained.

[0080] The specific implementation of step S21 can refer to step S11, and thus will not be described here.

[0081] In step S22, for each of a plurality of preset vehicle speeds, a plurality of steering torques measured at a plurality of steering angles at the vehicle speed are obtained, and the plurality of steering torques correspond one-to-one to the plurality of steering angles.

[0082] In some embodiments, the vehicle can be tested in advance to test the steering torque at different steering angles at different vehicle speeds. For example, the plurality of measured steering torques can be as shown in Table 1:

[0083] Table 1

[0084]

[0085] In step S23, the first steering torque interval is determined according to the steering torque corresponding to the steering angle less than the specified steering angle in the plurality of steering torques.

[0086] In some embodiments, for the same vehicle speed, the steering angles at the vehicle speed can be arranged in order from small to large. Since the steering torque is generally positively correlated with the steering angle, the ordering of the steering angles can also be used as the ordering of the steering torques at the vehicle speed from small to large. Then, the steering torque corresponding to the steering angle less than the specified steering angle can be divided into the first steering torque interval.

[0087] For example, the steering angles include steering angle a, steering angle b, steering angle c, …, arranged in order from small to large. If the specified steering angle is steering angle δ, steering angle b is less than steering angle δ, steering angle c is greater than steering angle δ, and the vehicle speed is vehicle speed 2, then the steering torque 2a corresponding to steering angle a, the steering torque 2b corresponding to steering angle b, and the steering torque arranged before steering torque 2a can be divided into the first steering torque interval.

[0088] Similarly, the first steering torque interval in the corresponding power-assisted characteristic curve can also be determined for other vehicle speeds by the above-described embodiments.

[0089] In step S24, the second steering torque interval is determined according to the steering torque corresponding to the steering angle greater than or equal to the specified steering angle in the plurality of steering torques.

[0090] With the above example, the hand torque 2c corresponding to the steering angle c and the hand torque arranged after the hand torque 2c can be divided into the second hand torque interval.

[0091] Similarly, the second hand torque interval in the corresponding assist characteristic curve can also be determined for other vehicle speeds through the above embodiment.

[0092] Alternatively, only the hand torque corresponding to the specified steering angle of the vehicle can be tested, and the hand torque is determined as the demarcation hand torque, and then the hand torque less than or equal to the demarcation hand torque and greater than the dead zone threshold is determined as the first hand torque interval, and the hand torque greater than the demarcation hand torque and less than or equal to the maximum hand torque of the vehicle is determined as the second hand torque interval.

[0093] In some embodiments, the above method further comprises a step S25 of determining a straight line segment in the assist characteristic curve corresponding to the first hand torque interval, wherein the step S25 can comprise:

[0094] In step S251, for each of a plurality of preset vehicle speeds, the maximum assist torque and the maximum hand torque of the vehicle at the vehicle speed are obtained.

[0095] As a way, the hand torque and the assist torque of the vehicle at each of a plurality of vehicle speeds can be tested in advance, for example, for a vehicle speed of 40Km / h, the user's ideal maximum hand torque and maximum assist torque can be tested.

[0096] Alternatively, the maximum hand torque can be the ideal maximum hand torque measured for a single user, or the maximum hand torque measured for a plurality of users can be analyzed by big data to obtain a maximum hand torque suitable for the general public. For example, if the user's ideal hand torque is measured to be in the range of [4, 7]Nm, the maximum hand torque is 7Nm.

[0097] Exemplarily, the maximum assist torque can be obtained in the following manner: the driver's hand torque T is calculated according to the multiplication of the vehicle steering wheel radius R and the ideal tangential force F exerted by the driver on the steering wheel h Taking into account the dead zone limit value T d0 , the actual torque value range [T d0 , T dmax ] exerted by the driver on the steering wheel can be determined. According to the empirical formula , the steering resistance torque T f is calculated, wherein f is the sliding friction coefficient between the tire and the road surface, which is generally taken as 0.7 according to the experience value; wherein G1 is the front axle load (N); P is the tire air pressure (MPa). The total torque T required to be provided on the steering wheel is calculated, wherein T zis the total torque provided on the steering wheel; L1 is the length of the steering rocker arm; L2 is the length of the steering knuckle arm; i w is the steering gear angular transmission ratio; η is the steering gear efficiency. z Subtract the maximum hand torque T from dmax The maximum assist torque T required by the motor can be obtained max Similarly, the assist torque at a certain vehicle speed is equal to the total torque minus the manual torque.

[0098] In step S252, the slope of the straight line segment is determined according to the maximum assist torque and the maximum hand torque.

[0099] For example, after obtaining the maximum assist torque T according to the above steps, max , maximum hand torque T dmax , dead zone threshold T d0 In the case of dmax and dead zone threshold T d0 The difference (T dmax -T d0 ), then calculate the maximum assist torque T max , and the maximum hand torque T dmax and dead zone threshold T d0 The difference (T dmax -T d0 ) and get T max / (T dmax -T d0 ), and the T max / (T dmax -T d0 ) is determined as the slope K of the straight line segment i .

[0100] In some embodiments, in step S252, the specific implementation of determining the slope of the straight line segment according to the maximum assist torque and the maximum hand torque may include:

[0101] In step S2521, the quotient of the maximum assist torque and the maximum hand torque is calculated to obtain a reference slope.

[0102] The specific implementation of step S2521 can refer to the specific implementation of step S242, so it will not be repeated here.

[0103] In step S2522, the reference slope is corrected by a preset correction value to obtain the straight line slope, which is smaller than the reference slope.

[0104] In some embodiments, in step S2522, the reference slope is corrected by a preset correction value to obtain the straight line slope. Specific implementations may include:

[0105] The sum of the preset correction value and the maximum hand torque is calculated to obtain the corrected maximum hand torque; the quotient of the maximum assist torque and the corrected maximum hand torque is calculated to obtain the slope of the straight line.

[0106] For example, the preset correction value is M, where M>0, and the maximum hand torque after correction can be T hmax =T dmax +M, and then the slope of the straight line segment Ki=T can be calculated based on the corrected maximum hand torque max / (T hmax -T d0 ).

[0107] For example, Figure 5 As shown, the slope of the straight line before correction is K1, and its corresponding line segment is Figure 5 The slope of the corrected line segment 1 is K2, and its corresponding line segment is Figure 5 For line segment 2, the slope K2 of the corrected straight line is smaller than the slope K1 of the straight line before correction.

[0108] In other implementations, the reference slope may be directly reduced by a preset correction value to correct the reference slope, wherein the preset correction value is greater than 0.

[0109] Considering that the curve corresponding to the second hand torque interval in the power-assistance characteristic curve requires a curve with a greater tangential slope than the linear slope, in this embodiment, a reference slope is obtained by calculating the quotient of the maximum power-assistance torque and the maximum hand torque. This reference slope is then corrected by a preset correction value to obtain the linear slope, which is smaller than the reference slope. This allows the linear slope to be appropriately reduced to ensure that it is smaller than the minimum slope of the curve corresponding to the second hand torque interval.

[0110] In step S253 , the straight line segment is determined based on the straight line slope and the minimum and maximum values ​​of the first hand torque interval.

[0111] Continuing with the above example, the minimum value of the first hand torque interval (ie, the dead zone threshold T d0 ), determine the horizontal coordinate of the starting point of the straight line segment, that is, get the starting point coordinate of the straight line segment (T d0 , 0). And according to the slope K i and the starting point coordinates (T d0 , 0), determine the expression of the straight line segment y = K i (xTd0 ). Then the abscissa of the end point of the straight line segment can be determined according to the maximum value of the first hand torque interval, i.e. the hand torque T dk corresponding to the specified steering angle, and the ordinate of the end point of the straight line segment can be determined according to the expression of the straight line segment, i.e. T dk corresponding to the specified steering angle, and the ordinate of the end point of the straight line segment can be determined according to the expression of the straight line segment, i.e. T i (x-T d0 ), T d0 ≤x≤T dk .

[0112] In some embodiments, the above method further comprises a step S26 of determining a curve segment in the boost characteristic curve corresponding to a second hand torque interval, wherein step S26 can comprise:

[0113] In step S261, the difference between the maximum value of the above-mentioned second hand torque interval and the minimum value of the above-mentioned first hand torque interval is calculated, and half of the above-mentioned difference is determined as the target abscissa.

[0114] For example, the difference (T dmax -T d0 ) between the maximum value T dmax of the above-mentioned second hand torque interval and the minimum value T d0 of the above-mentioned first hand torque interval is calculated, and (T dmax -T d0 ) / 2 is determined as the target abscissa.

[0115] In step S262, a reference ordinate is determined according to the above-mentioned target abscissa, the maximum value of the above-mentioned second hand torque interval, the minimum value of the above-mentioned first hand torque interval, and the maximum boost torque of the above-mentioned vehicle.

[0116] For example, the slope T max / (T dmax -T d0 ) of a reference straight line can be determined by the maximum boost torque T max , the maximum value T dmax of the second hand torque interval, and the minimum value T d0 of the first hand torque interval, and then the expression of the reference straight line can be determined by combining the slope of the reference straight line and the starting coordinates (T d0 , 0) of the reference straight line, and the reference ordinate corresponding to the target abscissa can be solved by substituting the target abscissa into the expression of the reference straight line.

[0117] In step S263, the above-mentioned reference ordinate is corrected to obtain a target ordinate, and the value of the above-mentioned target ordinate is smaller than the value of the above-mentioned reference ordinate.

[0118] For example, with reference to the reference ordinate Y1, the reference ordinate can be reduced by a preset value d to obtain a target ordinate Y2, where d is greater than 0, and Y2 = Y1 - d.

[0119] In step S264, a target coordinate is determined according to the target abscissa and the target ordinate.

[0120] In step S255, an expression of the curve segment is determined according to the maximum assist torque, the maximum hand torque, and the target coordinate.

[0121] In some embodiments, in step S265, the specific implementation of determining the expression of the curve segment according to the maximum assist torque, the maximum hand torque, and the target coordinate can include:

[0122] In step S2651, the maximum assist torque is taken as a first ordinate, and the maximum hand torque is taken as a first abscissa to obtain a first coordinate.

[0123] For example, according to the maximum assist torque T max and the maximum hand torque T dmax , a first coordinate (T dmax , T max ) can be obtained.

[0124] In step S2652, the minimum value of the first hand torque interval is taken as a second abscissa, and 0 is taken as a second ordinate to obtain a second coordinate.

[0125] For example, according to the minimum value T d0 of the first hand torque interval, a second coordinate (T d0 , 0) can be obtained.

[0126] In step S2653, the first coordinate, the second coordinate, and the target coordinate are brought into a preset curve formula to calculate parameters of the curve formula.

[0127] Using the above example, for example, the preset curve formula is a parabola formula, specifically y = a i *x 2 +b i *x 2 +c i , (i = 0, 1, 2, 3, …, n), where n is a positive integer, and i can be the number of the assist characteristic curve. Among them, the parameters (hereinafter referred to as coefficients) a i , b i , c iis unknown, so the coordinates on the curve need to be brought in to solve it. Therefore, the first coordinate, the second coordinate and the target coordinate can be brought into the preset curve formula, and the coefficients a i , b i , c i can be calculated.

[0128] In step S2654, based on the above parameters and the above preset curve formula, the expression of the above curve segment is determined.

[0129] Following the above example, after the coefficients a i , b i , c i are calculated, the parabola formula is replaced accordingly, and the expression of the curve segment is determined, wherein in the expression of the curve segment, T dk ≤x≤T dmax .

[0130] It can be understood that since the adjustment is made on the basis of the reference straight line, the vertical coordinate of the midpoint of the reference straight line is reduced, so that the curve opening upward can be obtained, even if the obtained curve segment has a concave feature, and the slope of the curve gradually increases with the increase of the hand torque (horizontal coordinate). As an example, as shown in Figure 6 , the reference straight line is a line segment 1, and the target coordinate obtained by reducing the vertical coordinate of the center of the reference straight line as the coordinate in the curve segment can ensure that the curve segment (line segment 2 in Figure 6 ) is upward opening.

[0131] In step S27, the target assist characteristic curve corresponding to the above vehicle speed is obtained from the plurality of assist characteristic curves pre-calibrated. Among them, the line segment corresponding to the first hand torque interval in the above assist characteristic curve is a straight line segment, the line segment corresponding to the second hand torque interval in the above assist characteristic curve is a curve segment opening upward, the maximum value of the above first hand torque interval is equal to or less than the minimum value of the above second hand torque interval, and the above assist characteristic curve represents the mapping relationship between the hand torque and the assist torque.

[0132] It can be understood that the maximum value of the above first hand torque interval is equal to or less than the minimum value of the above second hand torque interval, so the straight line segment and the curve segment can be continuous or discontinuous. For example, when the maximum value of the first hand torque interval is equal to the minimum value of the above second hand torque interval, the end of the straight line segment can be connected with the starting end of the curve segment. For example, when the maximum value of the first hand torque interval is less than the minimum value of the above second hand torque interval, the end of the straight line segment and the starting end of the curve segment can be disconnected, or can be connected through other transition curves, which are not limited here.

[0133] In step S28, the target assist torque is determined according to the hand torque and the target assist characteristic curve.

[0134] In some embodiments, the vehicle can also obtain the steering angle δ through the CAN network, and then match the obtained steering angle δ with the currently obtained hand torque, and if the matching is successful, step S27 is performed.

[0135] Optionally, a corresponding relationship between a plurality of steering angles and a plurality of hand torques can be measured in advance, and if the relationship between the currently obtained steering angle δ and the currently obtained hand torque satisfies the corresponding relationship, it is determined that the steering angle δ and the currently obtained hand torque are matched successfully.

[0136] In step S29, the assist torque of the steering wheel is adjusted to the target assist torque.

[0137] For example, in actual application, the specific implementation process of the vehicle control method can be as shown in Figure 7 As shown in Figure 7 The base assist module of the ECU can receive the hand torque Td and the steering angle δ (i.e. the steering wheel rotation angle) sent by the TAS sensor, and receive the vehicle speed V analyzed by the CAN network, and then the base assist module determines the target assist characteristic curve from the plurality of preset assist characteristic curves based on the vehicle speed V, and then determines the target assist torque (also referred to as target torque) according to the hand torque Td and the steering angle δ. Then the target torque is input to the motor control module, and the motor control module outputs the corresponding target current according to the target torque. As an example, the target torque can be T, and the motor control module can calculate the target current I of the assist motor according to the motor formula T = K * I, where K is the torque constant. Then the target current I is sent to the execution motor to control the execution motor to adjust the assist torque of the vehicle steering wheel to the target assist torque.

[0138] As shown in Figure 3 The assist characteristic curve can be divided into a no-assist zone, an assist zone, and a constant assist zone according to the hand torque. The no-assist zone is a hand torque less than a dead zone threshold, which does not provide assist. The assist zone is a dead zone threshold to a maximum hand torque, which provides a first straight line assist and a second curve assist. The constant assist zone provides constant assist between the maximum hand torque and the saturation torque, and stops assist when greater than the saturation torque, which is mainly to protect the motor and avoid damage to the related drive circuit. It can be seen that through the above-mentioned zoning, segmented control based on hand torque is realized.

[0139] It can be understood that Figure 2Only the schematic diagram of the boost characteristic curve corresponding to the positive (e.g. clockwise) hand torque applied by the user to the steering wheel is shown, and the boost characteristic curve corresponding to the negative (e.g. counterclockwise) hand torque applied by the user to the steering wheel is symmetrical about the origin (0, 0) of the coordinate center. Figure 2 The center is symmetrical about the origin (0, 0) of the coordinate.

[0140] It can be seen that the vehicle control method provided in the embodiment adopts the linear boost characteristic curve in small-angle steering, guarantees small data quantity, low requirement for the controller, good real-time performance and followability, adopts the curved boost characteristic curve in large-angle steering, and guarantees road feeling at high speed. Thus, the advantages of the linear boost characteristic curve and the curved boost characteristic curve are fully utilized, the steering convenience at low speed and the road feeling at high speed are better coordinated, and the performance of the EPS boost characteristic curve is more optimal.

[0141] More specific advantages are as follows:

[0142] (1) The linear boost curve is combined with the curved boost curve for segmented control, the transition is smooth in the control process, and the overall performance of the EPS is greatly improved. The linear boost characteristic curve is selected in the small-angle steering range, the control is simple, the data quantity is small, the real-time performance and followability are good, the curved boost characteristic curve with a larger slope is adopted in large-angle steering, and the steering convenience is considered.

[0143] (2) The linear boost characteristic curve is adopted in small-angle steering, the linear segment is longer and the proportion is larger as the vehicle speed is lower, the data quantity is small, the requirement for the controller is low, the real-time performance and followability are good, the curved boost characteristic curve is adopted in large-angle steering, the arc of the curved segment is longer and the proportion is larger as the vehicle speed is higher, and the steering road feeling is better.

[0144] (3) When the hand torque is at the dead zone boundary (i.e. the dead zone threshold), the process from no boost to boost or from boost to no boost will cause mutation and bring a certain impact to the steering wheel, resulting in poor driving comfort and smoothness. The segmented control can reduce the slope of the linear segment to a certain extent, reduce the mutation strength, alleviate the impact of the steering wheel near the dead zone boundary, and improve the steering stability, smoothness and comfort.

[0145] (4) The segmented control better coordinates the deficiencies of the curve type assist characteristic curve steering lightness, complex curve, large data storage, and inconvenient adjustment, which to some extent reduces the real-time performance of the EPS assist follow-up and the straight line type assist characteristic curve steering feeling. Compared with the segmented control strategy in the embodiment, the broken line type assist characteristic curve in the related technology is still relatively complex in algorithm, has a longer calculation time, needs more data, and has relatively poor steering lightness and feeling. Therefore, the vehicle control method provided in the embodiment is more practical, efficient, and economical.

[0146] Figure 8 is a block diagram of a vehicle control device according to an exemplary embodiment, as shown in Figure 8 The device 80 can include an information acquisition module 81, a target assist characteristic curve determination module 82, a target assist torque determination module 83, and a control module 84, wherein:

[0147] The information acquisition module 81 is configured to acquire the vehicle speed of the vehicle and the steering torque received by the steering wheel.

[0148] The target assist characteristic curve determination module 82 is configured to acquire a target assist characteristic curve corresponding to the vehicle speed from a plurality of assist characteristic curves pre-calibrated, wherein a line segment corresponding to a first steering torque interval in the assist characteristic curve is a straight line segment, a line segment corresponding to a second steering torque interval in the assist characteristic curve is a curve segment opening upward, the maximum value of the first steering torque interval is equal to or less than the minimum value of the second steering torque interval, and the assist characteristic curve represents a mapping relationship between the steering torque and the assist torque.

[0149] The target assist torque determination module 83 is configured to determine a target assist torque according to the steering torque and the target assist characteristic curve.

[0150] The control module 84 is configured to adjust the assist torque of the steering wheel to the target assist torque.

[0151] In some embodiments, the device 80 further includes:

[0152] The measurement module is configured to, for each of a plurality of preset vehicle speeds, acquire a plurality of steering torques measured at a plurality of steering angles of the vehicle at the vehicle speed, wherein the plurality of steering torques correspond one-to-one to the plurality of steering angles;

[0153] The first steering torque interval determination module is configured to determine the first steering torque interval according to the steering torque corresponding to a steering angle less than a specified steering angle in the plurality of steering torques;

[0154] The second hand torque interval module is configured to determine the second hand torque interval according to a hand torque corresponding to a steering angle greater than or equal to the specified steering angle in the plurality of hand torques.

[0155] In some embodiments, the apparatus 80 further comprises:

[0156] The torque acquisition module is configured to acquire, for each vehicle speed in a plurality of preset vehicle speeds, a maximum assist torque and a maximum hand torque of the vehicle at the vehicle speed.

[0157] The straight line slope determination module is configured to determine a straight line slope of the straight line segment according to the maximum assist torque and the maximum hand torque.

[0158] The expression of the straight line segment is determined based on the straight line slope and minimum and maximum values of the first hand torque interval.

[0159] In some embodiments, the straight line slope determination module is specifically configured to: calculate a quotient of the maximum assist torque and the maximum hand torque to obtain a reference slope; and correct the reference slope by a preset correction value to obtain the straight line slope, the straight line slope being less than the reference slope.

[0160] In some embodiments, the straight line slope determination module is specifically further configured to: calculate a sum of the preset correction value and the maximum hand torque to obtain a corrected maximum hand torque; and calculate a quotient of the maximum assist torque and the corrected maximum hand torque to obtain the straight line slope.

[0161] In some embodiments, the apparatus 80 further comprises:

[0162] The target abscissa determination module is configured to calculate a difference between a maximum value of the second hand torque interval and a minimum value of the first hand torque interval, and determine a half of the difference as a target abscissa.

[0163] The reference ordinate determination module is configured to determine a reference ordinate according to the target abscissa, the maximum value of the second hand torque interval, the minimum value of the first hand torque interval, and the maximum assist torque of the vehicle.

[0164] The correction module is configured to correct the reference ordinate to obtain a target ordinate, the target ordinate having a value less than a value of the reference ordinate.

[0165] The target coordinate determination module is configured to determine a target coordinate according to the target abscissa and the target ordinate.

[0166] The expression determination module is configured to determine the expression of the curve segment according to the maximum assist torque, the maximum hand torque and the target coordinate.

[0167] The expression determination module is specifically configured to: take the maximum assist torque as a first longitudinal coordinate and the maximum hand torque as a first transverse coordinate to obtain a first coordinate; take a minimum value of the first hand torque range as a second transverse coordinate and 0 as a second longitudinal coordinate to obtain a second coordinate; and bring the first coordinate, the second coordinate and the target coordinate into a preset curve formula to calculate a parameter of a parabola; and determine the expression of the curve segment based on the parameter and the preset curve formula.

[0168] As to the device in the above embodiments, the specific manner in which each module performs operations has been described in detail in the embodiments of the method, and will not be described in detail here.

[0169] Referring to Figure 9 , Figure 9 is a functional block diagram of a vehicle 900 according to an example embodiment. The vehicle 900 can be configured to operate in a fully or partially autonomous driving mode. For example, the vehicle 900 can obtain surrounding environment information through a perception system 920, and obtain an autonomous driving strategy based on analysis of the surrounding environment information to achieve full autonomous driving, or present the analysis result to a user to achieve partial autonomous driving.

[0170] The vehicle 900 can include various subsystems, such as an infotainment system 910, a perception system 920, a decision control system 930, a drive system 940, and a computing platform 950. Optionally, the vehicle 900 can include more or fewer subsystems, and each subsystem can include multiple components. In addition, each subsystem and component of the vehicle 900 can be interconnected by wired or wireless means.

[0171] In some embodiments, the infotainment system 910 can include a communication system 911, an entertainment system 912, and a navigation system 913.

[0172] The communication system 911 can include a wireless communication system that can communicate wirelessly with one or more devices, either directly or via a communication network. For example, the wireless communication system can use 3G cellular communication, such as CDMA, EVDO, GSM / GPRS, or 4G cellular communication, such as LTE. Or 5G cellular communication. The wireless communication system can communicate with a wireless local area network (WLAN) using WiFi. In some embodiments, the wireless communication system can communicate directly with a device using an infrared link, Bluetooth, or ZigBee. Other wireless protocols, such as various vehicle communication systems, for example, the wireless communication system can include one or more dedicated short range communications (DSRC) devices, which can include public and / or private data communication between vehicles and / or roadside stations.

[0173] The entertainment system 912 can include a display device, a microphone, and a sound system, based on which a user can listen to the radio or play music in the vehicle, or connect the phone with the vehicle and realize the phone screen projection on the display device. The display device can be touchable, and the user can operate it by touching the screen.

[0174] In some cases, the user's voice signal can be obtained through the microphone, and some control of the vehicle 900 by the user can be realized according to the analysis of the user's voice signal, such as adjusting the temperature in the vehicle, etc. In other cases, the user can be played music through the sound system.

[0175] The navigation system 913 can include a map service provided by a map provider, thereby providing the vehicle 900 with navigation of the driving route, and the navigation system 913 can be used in cooperation with the global positioning system 921 and the inertial measurement unit 922 of the vehicle. The map service provided by the map provider can be a two-dimensional map or a high-definition map.

[0176] The perception system 920 can include several types of sensors that sense information about the environment surrounding the vehicle 900. For example, the perception system 920 can include a global positioning system 921 (which can be a GPS system, a Beidou system, or other positioning system), an inertial measurement unit (IMU) 922, a lidar 923, a millimeter wave radar 924, an ultrasonic radar 925, and a camera 926. The perception system 920 can also include sensors that monitor the internal systems of the vehicle 900 (e.g., an in-vehicle air quality monitor, a fuel gauge, an oil temperature gauge, etc.). Sensor data from one or more of these sensors can be used to detect objects and their respective characteristics (location, shape, direction, velocity, etc.). Such detection and identification are key functions for the safe operation of the vehicle 900.

[0177] The global positioning system 921 is used to estimate the geographic position of the vehicle 900.

[0178] The inertial measurement unit 922 is used to sense changes in the pose of the vehicle 900 based on inertial acceleration. In some embodiments, the inertial measurement unit 922 can be a combination of an accelerometer and a gyroscope.

[0179] The lidar 923 uses laser light to sense objects in the environment in which the vehicle 900 is located. In some embodiments, the lidar 923 can include one or more laser sources, a laser scanner, and one or more detectors, as well as other system components.

[0180] The millimeter wave radar 924 uses radio signals to sense objects within the surrounding environment of the vehicle 900. In some embodiments, in addition to sensing objects, the millimeter wave radar 924 can also be used to sense the speed and / or direction of advance of the objects.

[0181] The ultrasonic radar 925 can use ultrasonic signals to sense objects around the vehicle 900.

[0182] The camera 926 is used to capture image information of the surrounding environment of the vehicle 900. The camera 926 can include a monocular camera, a binocular camera, a structured light camera, and a panoramic camera, etc., and the image information obtained by the camera 926 can include still images or video stream information.

[0183] The decision control system 930 includes a computing system 931 that makes analytical decisions based on the information obtained by the perception system 920, and also includes a vehicle controller 932 that controls the power system of the vehicle 900, as well as a steering system 933, a throttle 934, and a braking system 935 for controlling the vehicle 900.

[0184] The computing system 931 can operate to process and analyze various information acquired by the perception system 920 in order to identify targets, objects, and / or features in the environment surrounding the vehicle 900. Targets can include pedestrians or animals, and objects and / or features can include traffic signals, road boundaries, and obstacles. The computing system 931 can use object recognition algorithms, Structure from Motion (SFM) algorithms, video tracking, and / or the like. In some embodiments, the computing system 931 can be used to map the environment, track objects, estimate the velocity of objects, and / or the like. The computing system 931 can analyze the acquired information and derive a control strategy for the vehicle.

[0185] The vehicle controller 932 can be used to coordinate the control of the power battery and the engine 941 of the vehicle in order to improve the power performance of the vehicle 900.

[0186] The steering system 933 can be used to adjust the heading direction of the vehicle 900. For example, the steering system 933 can be a steering wheel system in one embodiment.

[0187] The throttle 934 can be used to control the operating speed of the engine 941 and, in turn, the speed of the vehicle 900.

[0188] The braking system 935 can be used to control the deceleration of the vehicle 900. The braking system 935 can use friction to slow the wheels 944. In some embodiments, the braking system 935 can convert the kinetic energy of the wheels 944 into electrical current. The braking system 935 can also take other forms to slow the wheels 944 and, in turn, control the speed of the vehicle 900.

[0189] The drive system 940 can include components that provide motive power for the vehicle 900. In one embodiment, the drive system 940 can include the engine 941, the energy source 942, the transmission system 943, and the wheels 944. The engine 941 can be an internal combustion engine, an electric motor, an air compression engine, or other types of engines in combination, such as a hybrid engine that includes a gasoline engine and an electric motor, a hybrid engine that includes an internal combustion engine and an air compression engine. The engine 941 converts the energy source 942 into mechanical energy.

[0190] Examples of the energy source 942 include gasoline, diesel, other petroleum-based fuels, propane, other compressed gas-based fuels, ethanol, solar panels, batteries, and other sources of electrical power. The energy source 942 can also provide energy for other systems of the vehicle 900.

[0191] The drivetrain 943 can transmit mechanical power from the engine 941 to the wheels 944. The drivetrain 943 can include a transmission, a differential, and drive shafts. In one embodiment, the drivetrain 943 can also include other devices, such as a clutch. The drive shafts can include one or more shafts that can be coupled to one or more wheels 944.

[0192] Some or all of the functionality of the vehicle 900 is controlled by a computing platform 950. The computing platform 950 can include at least one processor 951 that can execute instructions 953 stored in a non-transitory computer readable medium, such as a memory 952. In some embodiments, the computing platform 950 can also be a plurality of computing devices that control individual components or subsystems of the vehicle 900 in a distributed manner.

[0193] The processor 951 can be any conventional processor, such as a commercially available CPU. Alternatively, the processor 951 can include a Graphics Processing Unit (GPU), a Field Programmable Gate Array (FPGA), a System on Chip (SOC), an Application Specific Integrated Circuit (ASIC), or a combination thereof. Although Figure 9 Although functionally illustrated as a single processor, memory, and other elements of a computer in the same block, one of ordinary skill in the art will appreciate that the processor, computer, or memory can actually include multiple processors, computers, or memories that can or can not be stored in the same physical housing. For example, the memory can be a hard drive or other storage medium located in a different housing than the computer. Accordingly, references to a processor or computer will be understood to include references to a collection of processors or computers or memories that can or can not operate in parallel. Rather than using a single processor to perform the steps described herein, some components, such as the steering assembly and the deceleration assembly, can each have their own processor that only performs calculations related to the functionality specific to the component. The computing platform 950 can be equivalent to the on-board computer in the above-described embodiments.

[0194] In the embodiments of the present disclosure, the processor 951 can perform the vehicle control method described above.

[0195] In various aspects described herein, the processor 951 can be located remotely from the vehicle and in wireless communication with the vehicle. In other aspects, some of the processes described herein are performed on a processor disposed within the vehicle while others are performed by a remote processor, including taking the necessary steps to perform a single maneuver.

[0196] In some embodiments, the memory 952 can include instructions 953 (e.g., program logic) that can be executed by the processor 951 to perform various functions of the vehicle 900. The memory 952 can also include additional instructions, including instructions to send data to, receive data from, interact with, and / or control one or more of the infotainment system 910, the perception system 920, the decision control system 930, and the drive system 940.

[0197] In addition to the instructions 953, the memory 952 can store data, such as road maps, route information, the vehicle's position, orientation, speed, and other such vehicle data, and other information. Such information can be used by the vehicle 900 and the computing platform 950 during operation of the vehicle 900 in autonomous, semi-autonomous, and / or manual modes.

[0198] The computing platform 950 can control the functions of the vehicle 900 based on inputs received from various subsystems, such as the drive system 940, the perception system 920, and the decision control system 930. For example, the computing platform 950 can utilize inputs from the decision control system 930 in order to control the steering system 933 to avoid obstacles detected by the perception system 920. In some embodiments, the computing platform 950 can be operable to provide control over many aspects of the vehicle 900 and its subsystems.

[0199] Optionally, one or more of the components described above can be installed separately from or associated with the vehicle 900. For example, the memory 952 can exist partially or entirely separately from the vehicle 900. The components described above can be communicatively coupled together in a wired and / or wireless manner.

[0200] Optionally, the above components are just an example, in actual applications, components in each module described above can be added or deleted according to actual needs, Figure 9 It should not be understood as a limitation to the embodiments of the present disclosure.

[0201] An autonomous vehicle traveling on a roadway, such as the vehicle 900 above, can identify objects within its surroundings to determine an adjustment to a current speed. The objects can be other vehicles, traffic control devices, or other types of objects. In some examples, each identified object can be considered independently, and based on respective characteristics of the object, such as its current speed, acceleration, spacing from the vehicle, etc., can be used to determine a speed at which the autonomous vehicle is to adjust.

[0202] Optionally, the vehicle 900 or a perception and computing device (e.g., the computing system 931, the computing platform 950) associated with the vehicle 900 can predict the behavior of the identified object based on the characteristics of the identified object and the state of the surrounding environment (e.g., traffic, rain, ice on the road, etc.). Optionally, each identified object depends on the behavior of the other identified objects, so the behavior of a single identified object can also be predicted by considering all the identified objects together. The vehicle 900 can adjust its speed based on the predicted behavior of the identified object. In other words, the autonomous vehicle can determine what steady state the vehicle will need to adjust to (e.g., accelerate, decelerate, or stop) based on the predicted behavior of the object. Other factors can also be considered in determining the speed of the vehicle 900 during this process, such as the lateral position of the vehicle 900 in the road, the curvature of the road, the proximity of static and dynamic objects, etc.

[0203] In addition to providing instructions to adjust the speed of the autonomous vehicle, the computing device can also provide instructions to modify the steering angle of the vehicle 900 to cause the autonomous vehicle to follow a given trajectory and / or maintain a safe lateral and longitudinal distance from objects in the vicinity of the autonomous vehicle (e.g., vehicles in adjacent lanes on the road).

[0204] The vehicle 900 described above can be various types of travel tools, such as a car, a truck, a motorcycle, a bus, a ship, an airplane, a helicopter, an amusement vehicle, a train, etc., and the embodiments of the present disclosure are not particularly limited.

[0205] In another exemplary embodiment, a computer program product is also provided, which contains a computer program capable of being executed by a programmable device, and the computer program has code portions for executing the vehicle control method described above when executed by the programmable device.

[0206] In another exemplary embodiment, a computer readable storage medium including program instructions that, when executed by a processor, implement the steps of the vehicle control method described above is also provided. For example, the computer readable storage medium can be the memory 952 described above including program instructions that are executable by the processor 951 of the vehicle 900 to complete the vehicle control method described above.

[0207] The preferred embodiments of the present disclosure are described in detail above with reference to the accompanying drawings, but the present disclosure is not limited to the specific details in the above-described embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

[0208] It should be further noted that various specific technical features described in the above specific embodiments can be combined in any suitable manner, and the disclosure will not be repeated here for various possible combinations.

[0209] In addition, various different embodiments of the disclosure can also be combined with each other as long as they do not contradict the idea of the disclosure, and they should also be considered as disclosed by the disclosure.

Claims

1. A vehicle control method, characterized in that: include: Obtaining the vehicle speed and the hand torque applied to the steering wheel; obtaining a target power-assistance characteristic curve corresponding to the vehicle speed from a plurality of pre-calibrated power-assistance characteristic curves, wherein a line segment corresponding to a first hand torque interval in the power-assistance characteristic curve is a straight line segment, a line segment corresponding to a second hand torque interval in the power-assistance characteristic curve is a curve segment opening upward, a maximum value of the first hand torque interval is equal to or less than a minimum value of the second hand torque interval, and the power-assistance characteristic curve represents a mapping relationship between hand torque and power-assistance torque; determining a target power-assisting torque according to the hand torque and the target power-assisting characteristic curve; adjusting the steering wheel assist torque to the target assist torque; The method further comprises: For each of a plurality of preset vehicle speeds, obtaining a plurality of hand torques measured at a plurality of steering angles at the vehicle speed, wherein the plurality of hand torques correspond one-to-one to the plurality of steering angles; determining the first hand torque interval according to the hand torque corresponding to the steering angle smaller than the specified steering angle among the multiple hand torques; determining the second hand torque interval according to the hand torque corresponding to the steering angle greater than or equal to the specified steering angle among the multiple hand torques; Calculating a difference between a maximum value of the second hand torque interval and a minimum value of the first hand torque interval, and determining half of the difference as a target horizontal coordinate; determining a reference vertical coordinate according to the target horizontal coordinate, the maximum value of the second hand torque interval, the minimum value of the first hand torque interval, and the maximum power-assisting torque of the vehicle; Correcting the reference ordinate to obtain a target ordinate, wherein the value of the target ordinate is smaller than the value of the reference ordinate; Determining target coordinates according to the target horizontal coordinate and the target vertical coordinate; An expression for the curve segment is determined according to the maximum assist torque, the maximum hand torque, and the target coordinates.

2. The method according to claim 1, characterized in that The method further comprises: For each of a plurality of preset vehicle speeds, obtaining a maximum power assist torque and a maximum hand torque of the vehicle at the speed; determining a straight line slope of the straight line segment according to the maximum assist torque and the maximum hand torque; An expression for the straight line segment is determined based on the slope of the straight line and the minimum and maximum values ​​of the first hand torque interval.

3. The method according to claim 2, characterized in that Determining the slope of the straight line segment according to the maximum assist torque and the maximum hand torque includes: Calculating the quotient of the maximum assist torque and the maximum hand torque to obtain a reference slope; The reference slope is corrected by a preset correction value to obtain the straight line slope, which is smaller than the reference slope.

4. The method according to claim 3, characterized in that The step of correcting the reference slope by using a preset correction value to obtain the straight line slope includes: Calculating the sum of the preset correction value and the maximum hand torque to obtain a corrected maximum hand torque; The quotient of the maximum assist torque and the corrected maximum hand torque is calculated to obtain the slope of the straight line.

5. The method according to claim 1, characterized in that The expression for determining the curve segment according to the maximum assist torque, the maximum hand torque, and the target coordinates includes: The maximum assist torque is used as a first ordinate, and the maximum hand torque is used as a first abscissa to obtain a first coordinate; The minimum value of the first hand torque interval is used as the second abscissa and 0 is used as the second ordinate to obtain a second coordinate; Substituting the first coordinate, the second coordinate, and the target coordinate into a preset curve formula to calculate parameters of the curve formula; An expression of the curve segment is determined based on the parameters and the preset curve formula.

6. A vehicle control device, characterized in that: include: an information acquisition module configured to acquire the vehicle speed and the hand torque applied to the steering wheel; a target power-assistance characteristic curve determination module configured to obtain a target power-assistance characteristic curve corresponding to the vehicle speed from a plurality of pre-calibrated power-assistance characteristic curves, wherein a line segment corresponding to a first hand torque interval in the power-assistance characteristic curve is a straight line segment, a line segment corresponding to a second hand torque interval in the power-assistance characteristic curve is a curve segment opening upward, a maximum value of the first hand torque interval is equal to or less than a minimum value of the second hand torque interval, and the power-assistance characteristic curve represents a mapping relationship between hand torque and power-assistance torque; a target assist torque determination module, configured to determine a target assist torque according to the hand torque and the target assist characteristic curve; a control module configured to adjust the steering wheel assist torque to the target assist torque; The vehicle control device further includes: a measuring module configured to obtain, for each of a plurality of preset vehicle speeds, a plurality of hand torques measured at a plurality of steering angles at the vehicle speed, wherein the plurality of hand torques correspond one-to-one to the plurality of steering angles; a first hand torque interval determining module configured to determine the first hand torque interval according to a hand torque corresponding to a steering angle smaller than a specified steering angle among the multiple hand torques; a second hand torque interval module, configured to determine the second hand torque interval according to the hand torque corresponding to the steering angle greater than or equal to the specified steering angle among the multiple hand torques; a target horizontal coordinate determining module, configured to calculate a difference between a maximum value of the second hand torque interval and a minimum value of the first hand torque interval, and determine half of the difference as a target horizontal coordinate; a reference ordinate determination module, configured to determine a reference ordinate according to the target abscissa, a maximum value of the second hand torque interval, a minimum value of the first hand torque interval, and a maximum assist torque of the vehicle; a correction module configured to correct the reference vertical coordinate to obtain a target vertical coordinate, wherein the value of the target vertical coordinate is smaller than the value of the reference vertical coordinate; a target coordinate determination module, configured to determine the target coordinates according to the target horizontal coordinate and the target vertical coordinate; The curve segment expression determination module is configured to determine the expression of the above curve segment according to the maximum assist torque, the maximum hand torque and the target coordinates.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

8. A vehicle, characterized in that: include: a memory having a computer program stored thereon; A processor, configured to execute the computer program in the memory to implement the steps of the method according to any one of claims 1 to 5.

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