Vehicle steering performance index determination method, vehicle steering limit soft and hard judgment method, storage medium and electronic device

Abstract

The application discloses a vehicle steering performance index determination method, a vehicle steering limiting soft and hard judgment method, a storage medium and an electronic device, wherein the vehicle steering performance index determination method comprises the following steps: acquiring a steering wheel steering angle and torque curve of a vehicle in a set steering angle interval; segmenting the steering wheel steering angle and torque curve, and acquiring a curve gradient and a curve dispersion degree of each segment curve; and determining a vehicle steering performance index according to the curve gradient and the curve dispersion degree of each segment curve. The steering wheel steering angle and torque curve are acquired from test data obtained by objective testing of steering performance, and the curve gradient and the curve dispersion degree of each segment curve are analyzed, so that change data indexes of a torque with a steering wheel rotation angle in a left turning area, a right turning area and a median area during vehicle steering are obtained, thereby reflecting subjective feelings of a driver during vehicle steering.

Description

Technical Field

[0001] This invention relates to the field of vehicle steering, and in particular to a method for determining vehicle steering performance indicators, a method for judging the soft and hard limits of vehicle steering, a storage medium, and an electronic device. Background Technology

[0002] Objective testing of a vehicle's steering performance is a crucial step in ensuring vehicle safety and handling. Through a series of scientific and systematic testing methods, a vehicle's steering performance is evaluated, thereby ensuring that the vehicle possesses good handling and safety during driving.

[0003] However, there is a significant discrepancy between the objective test indicators for steering performance and the driver's subjective feelings, resulting in a low degree of correlation between the two; the objective test indicators cannot reflect the driver's subjective feelings. Summary of the Invention

[0004] The main objective of this invention is to provide a method for determining vehicle steering performance indicators. This method aims to convert test data obtained from objective steering performance tests into data indicators that reflect the driver's subjective feelings, thereby improving the consistency between objective and subjective indicators. This will help to design products with better steering performance by targeting user needs in vehicle development.

[0005] To achieve the above objectives, the present invention proposes a method for determining vehicle steering performance indicators, the method comprising:

[0006] Obtain the steering wheel angle and torque curve of the vehicle within a set steering angle range;

[0007] The steering wheel angle and torque curve are segmented, and the curve gradient and curve dispersion of each segment are obtained.

[0008] The vehicle steering performance indicators are determined based on the curve gradient and curve dispersion of each curve segment.

[0009] Optionally, segmenting the steering wheel angle versus torque curve includes:

[0010] Based on the comparison between the steering wheel angle and the first and second set angles, the steering wheel angle and torque curve is divided into a left-turn region, a right-turn region, and a center region; wherein, the first set angle is smaller than the second set angle.

[0011] Based on the positional relationship between the steering wheel angle and torque curve located in the left-turn area, right-turn area, and center area, the steering wheel angle and torque curve are divided into six segments.

[0012] Optionally, the step of dividing the steering wheel angle and torque curve into a left-turn region, a right-turn region, and a center region based on the comparison between the steering wheel angle and a first set angle and a second set angle includes:

[0013] If the steering wheel angle is less than or equal to the first set angle, then the steering wheel angle is divided into a left turn area;

[0014] If the steering wheel angle is greater than the first set angle and less than or equal to the second set angle, then the steering wheel angle is divided into the middle region.

[0015] If the steering wheel angle is greater than the second set angle, then the steering wheel angle is designated as a right turn zone.

[0016] Optionally, obtaining the curve gradient and curve dispersion of each curve segment includes:

[0017] Obtain the dispersion of each curve segment;

[0018] Each segment of the curve was fitted using a straight line;

[0019] Obtain the slope value of the straight line corresponding to each curve segment, and use it as the curve gradient of that segment.

[0020] Optionally, determining the vehicle steering performance index based on the curve gradient and curve dispersion of each curve segment includes:

[0021] Based on the curve gradients of the two curve segments in each region, determine their arithmetic mean and use it as the average gradient value of that region, thereby obtaining the gradient values ​​of the left-turn region, the right-turn region, and the median region.

[0022] Obtain the difference and sum of the curve gradients of the two curve segments within each region;

[0023] Calculate the ratio of the difference to the sum, and use the absolute value of this ratio as the gradient symmetry of the region where the corresponding curve is located, thereby obtaining the gradient symmetry of the left-turning region, the gradient symmetry of the right-turning region, and the gradient symmetry of the median region.

[0024] Optionally, determining the vehicle steering performance index based on the curve gradient and curve dispersion of each curve segment further includes:

[0025] Based on the gradient values ​​of the left-turn and right-turn regions, their arithmetic mean is determined and used as the evaluation gradient value for the change in left / right turning torque.

[0026] Obtain the difference and sum of the gradient values ​​in the left-turn region and the right-turn region;

[0027] Calculate the ratio of the difference to the sum, and use the absolute value of this ratio as the symmetry of the left / right turning torque change.

[0028] Optionally, determining the vehicle steering performance index based on the curve gradient and curve dispersion of each curve segment further includes:

[0029] The difference between the gradient value of the median region and the evaluation gradient value of the left / right turning torque change is calculated.

[0030] The ratio of the difference to the gradient value of the median region is calculated and used as the relative difference between the median and non-median moment gradients.

[0031] Calculate the arithmetic mean of the curve dispersion of each segment and use it as the torque fluctuation of the vehicle.

[0032] This invention also proposes a method for determining the softness or hardness of vehicle steering limit, the method comprising:

[0033] Obtain the vehicle's steering wheel angle and torque curve;

[0034] The steering wheel angle and torque curve within the preset limit range are fitted using a cubic polynomial.

[0035] Calculate the radius of curvature of the cubic polynomial fitted curve;

[0036] The stiffness or softness of the vehicle steering limit is determined based on the comparison between the radius of curvature value and the set value.

[0037] The present invention also proposes a storage medium storing a vehicle steering performance index determination program, wherein when the vehicle steering performance index determination program is executed by a processor, the steps of the vehicle steering performance index determination method are implemented.

[0038] Alternatively, the storage medium stores a vehicle steering limit soft / hard determination program, which, when executed by the processor, implements the steps of the vehicle steering limit soft / hard determination method.

[0039] The present invention also proposes an electronic device, the electronic device comprising a processor and the aforementioned storage medium.

[0040] This invention discloses a method for determining vehicle steering performance indicators. The method includes: acquiring the steering wheel angle and torque curves of a vehicle within a set turning angle range; segmenting the steering wheel angle and torque curves and acquiring the curve gradient and curve dispersion of each segment; and determining the vehicle steering performance indicators based on the curve gradient and curve dispersion of each segment. This invention obtains the steering wheel angle and torque curves from test data obtained from objective steering performance tests, and then analyzes the curve gradient and curve dispersion of each segment to obtain data indicators showing the change in torque with steering wheel rotation angle in the left-turn, right-turn, and center regions when the vehicle is turning. This reflects the driver's subjective feeling when steering the vehicle; it is beneficial for designing products with superior steering performance by targeting user needs in vehicle development. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0042] Figure 1 This is a flowchart illustrating an embodiment of the vehicle steering performance index determination method of the present invention;

[0043] Figure 2 This is a flowchart illustrating another embodiment of the method for determining vehicle steering performance indicators of the present invention;

[0044] Figure 3 This is a flowchart illustrating another embodiment of the method for determining vehicle steering performance indicators according to the present invention.

[0045] Figure 4 This is a flowchart illustrating another embodiment of the method for determining vehicle steering performance indicators according to the present invention.

[0046] Figure 5 This is a flowchart illustrating another embodiment of the method for determining vehicle steering performance indicators according to the present invention.

[0047] Figure 6 This is a schematic diagram of the first steering wheel angle and steering wheel torque curve in an embodiment of the vehicle steering performance index determination method of the present invention;

[0048] Figure 7 This is a schematic diagram of the second steering wheel angle and steering wheel torque curve in an embodiment of the vehicle steering performance index determination method of the present invention.

[0049] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0051] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0052] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0053] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0054] Objective testing of a vehicle's steering performance is a crucial step in ensuring vehicle safety and handling. Through a series of scientific and systematic testing methods, a vehicle's steering performance is evaluated to ensure good handling and safety during driving. However, current objective testing indicators for steering performance differ significantly from the driver's subjective experience, resulting in a low degree of correlation; objective testing indicators cannot reflect the driver's subjective feelings. For the driver, the direct experience when turning the vehicle is the force required to turn the steering wheel and the smoothness of the change in required force as the steering wheel angle changes.

[0055] This invention proposes a method for determining vehicle steering performance indicators, referring to... Figure 1 The method for determining the vehicle steering performance index includes:

[0056] Step S10: Obtain the steering wheel angle and torque curve of the vehicle within the set turning angle range.

[0057] It should be noted that the angle range of the set turning angle interval can be symmetrical about 0°. This solution integrates vehicle steering test data to obtain the vehicle's steering wheel angle and torque curve. In one example, the steering wheel angle and torque curve can be obtained during a steering wheel center area experiment. In this step, the vehicle can be rotated according to the steering wheel angle within the set turning angle interval, or the curve of the set turning angle interval can be extracted from the original steering wheel angle and torque curve. The specific set turning angle interval is determined by the R&D personnel.

[0058] It should be noted that, due to the symmetrical setting of the turning angle range, the initial steering wheel angle is 0°. When the vehicle turns, the steering wheel first needs to turn to one side, then to the other side, and finally return to the 0° angle. Because there is a lag in steering wheel rotation, the curves formed by the steering wheel rotation and the return rotation do not coincide. That is, within the set turning angle range, each steering wheel angle corresponds to two torque values.

[0059] Step S20: Divide the steering wheel angle and torque curve into segments, and obtain the curve gradient and curve dispersion of each segment.

[0060] Reference Figure 2 Specifically, in step S210, based on the comparison between the steering wheel angle and the first set angle and the second set angle, the steering wheel angle and torque curve are divided into a left-turn region, a right-turn region and a center region; wherein, the first set angle is smaller than the second set angle.

[0061] It's easy to understand that the steering wheel has three states: left turn, maintaining the center position, and right turn. The steering wheel angle and torque curves corresponding to these three states may differ. Assuming the center position region consists of a first set angle and a second set angle, the steering wheel angle can be compared with both the first and second set angles.

[0062] The method of dividing the steering wheel angle and torque curve into a left-turn region, a right-turn region, and a center region based on the comparison between the steering wheel angle and a first set angle and a second set angle includes:

[0063] Reference Figure 3 Step S2110: If the steering wheel angle is less than or equal to the first set angle, then the steering wheel angle is divided into a left turn area.

[0064] Step S2120: If the steering wheel angle is greater than the first set angle and less than or equal to the second set angle, then the steering wheel angle is divided into the middle region.

[0065] Step S2130: If the steering wheel angle is greater than the second set angle, then the steering wheel angle is divided into a right turn area.

[0066] The first set angle is less than 0° and the second set angle is less than 0°. After determining the three regions, the steering wheel angle and torque curve are divided into three parts. Furthermore, because each steering wheel angle corresponds to two torque values ​​within the set angle range of the steering wheel angle and torque curve, each region contains two curve segments.

[0067] Step S220: Based on the positional relationship between the steering wheel angle and torque curve located in the left-turn area, right-turn area, and center area, the steering wheel angle and torque curve are divided into six segments.

[0068] Referring to Figure 6, obtaining the curve gradient and curve dispersion of each curve segment includes:

[0069] Obtain the dispersion of each curve segment;

[0070] Each segment of the curve was fitted using a straight line;

[0071] Obtain the slope value of the straight line corresponding to each curve segment, and use it as the curve gradient of that segment.

[0072] It should be noted that in the steering wheel angle versus torque curve, the torque is an analog quantity. The torque fluctuates with changes in angle, and this fluctuation directly affects the driver's driving experience. The dispersion of the curve can represent the amount of torque fluctuation during steering. The curve is not a non-linear curve; however, it is used as a reference. Figure 6We can use straight lines to fit each segment of the curve separately, and then plot a line graph on the original image to clearly show the changes in the curve. Figure 6 It can be seen that the curve gradient of each segment is roughly the same. We can first obtain the slope value of the fitted line corresponding to each segment of the curve and use it as the curve gradient of that segment.

[0073] Step S30: Determine the vehicle steering performance index based on the curve gradient and curve dispersion of each curve segment.

[0074] It should be noted that the vehicle steering performance indicators can reflect the driver's subjective feelings, and reflect the magnitude of the steering torque required when the steering wheel is turned, whether the torque change gradient is consistent, whether the left and right steering torques are symmetrical, and whether the steering torque change is smooth.

[0075] Reference Figure 4 The determination of vehicle steering performance indicators based on the curve gradient and curve dispersion of each curve segment includes:

[0076] Step S310: Determine the arithmetic mean of the curve gradients of the two curve segments in each region and use it as the average gradient value of the region, thereby obtaining the gradient value of the left-turn region, the gradient value of the right-turn region, and the gradient value of the median region.

[0077] Specifically, since the steering wheel angle and torque curve have three regions, they need to be calculated separately.

[0078] The formula for calculating the gradient value of the median region is as follows:

[0079]

[0080] in, The gradient value of the median region is referred to... Figure 6 k2 is the gradient of the second curve segment, and k5 is the gradient of the fifth curve segment. k2 and k5 represent the degree of torque change in the mid-range region during forward and backward rotations, respectively. This indicates the degree of torque variation in the median region. If the value is large, the torque required to turn a certain angle is large, making people feel that the median torque is heavy and the sense of median is strong. If the value is small, people feel that the median torque is light and the sense of median is vague.

[0081] The formula for calculating the gradient value of the left-turn region is as follows:

[0082]

[0083] in, The gradient value of the left-turn area is referred to... Figure 6 k is the gradient of the first curve segment, and k4 is the gradient of the fourth curve segment. This indicates the degree of torque change in the overall left-turn area; a larger value makes the left-turn non-center steering force feel lighter, while a larger value makes the left-turn non-center steering force feel heavier.

[0084] The formula for calculating the gradient value of the right-turn region is as follows:

[0085]

[0086] in, The gradient value of the right-turn region is referred to... Figure 6 k3 is the gradient of the third curve segment, and k6 is the gradient of the sixth curve segment. This indicates the degree of torque change in the overall right-turn area; a larger value makes the steering force feel lighter when turning right out of the center position, while a larger value makes the steering force feel heavier when turning right out of the center position.

[0087] Step S320: Obtain the difference and sum of the curve gradients of the two curve segments in each region.

[0088] Step S330: Calculate the ratio of the difference to the sum, and use the absolute value of the ratio as the gradient symmetry of the region where the corresponding curve is located, thereby obtaining the gradient symmetry of the left-turning region, the gradient symmetry of the right-turning region, and the gradient symmetry of the median region.

[0089] The formula for calculating the gradient symmetry of the median region is as follows:

[0090]

[0091] in, Let k2 be the gradient symmetry of the mid-range region, k5 be the gradient of the second curve segment, and k5 be the gradient of the fifth curve segment. The gradient symmetry of the mid-range region characterizes the consistency of the gradient of the steering wheel torque change in both directions near the mid-range.

[0092] The formula for calculating the gradient symmetry of the left-turn region is as follows:

[0093]

[0094] in, Let k1 be the gradient symmetry of the left-turn area, and k4 be the gradient of the first curve segment and k4 be the gradient of the fourth curve segment. The gradient symmetry of the left-turn area characterizes the consistency of the steering wheel torque change gradient in both directions during a left turn. If the gradient symmetry of the left-turn area is large, it will make the steering wheel feel inconsistent in terms of torque change gradients when turning outwards and returning to the starting position, indicating a problem with the steering system.

[0095] The formula for calculating the gradient symmetry of the right-turn region is as follows:

[0096]

[0097] in, Let k3 be the gradient symmetry of the right-turn area, k6 be the gradient of the third curve segment, and k6 be the gradient of the sixth curve segment. The gradient symmetry of the right-turn area characterizes the consistency of the steering wheel torque change gradient in both directions when turning right. If the gradient symmetry value of the right-turn area is large, it will make the driver feel that the torque change gradient when turning the steering wheel outwards and returning it is inconsistent.

[0098] This invention discloses a method for determining vehicle steering performance indicators. The method includes: acquiring the steering wheel angle and torque curves of a vehicle within a set turning angle range; segmenting the steering wheel angle and torque curves and acquiring the curve gradient and curve dispersion of each segment; and determining the vehicle steering performance indicators based on the curve gradient and curve dispersion of each segment. This invention obtains the steering wheel angle and torque curves from test data obtained from objective steering performance tests, and then analyzes the curve gradient and curve dispersion of each segment to obtain data indicators showing the change in torque with steering wheel rotation angle in the left-turn, right-turn, and center regions when the vehicle is turning. This reflects the driver's subjective feeling when steering the vehicle; it is beneficial for designing products with superior steering performance by targeting user needs in vehicle development.

[0099] In one embodiment, determining the vehicle steering performance index based on the curve gradient and curve dispersion of each curve segment further includes:

[0100] Step S340: Determine the arithmetic mean of the gradient values ​​of the left-turn area and the right-turn area and use it as the evaluation gradient value of the change in left / right turning torque.

[0101] The calculation formula for the evaluation gradient value of the left / right turning torque change is as follows:

[0102]

[0103] in, The evaluation gradient value is the change in left / right turning torque. This represents the gradient value for the left-turn region. This represents the gradient value for the right-turn region. If... A smaller value makes the non-neutral steering force feel lighter; if A larger value makes the steering force feel heavier when the steering wheel is not in the center position.

[0104] Step S350: Obtain the difference and sum of the gradient values ​​of the left-turn region and the right-turn region.

[0105] Step S360: Calculate the ratio of the difference to the sum, and use the absolute value of the ratio as the symmetry of the left / right turning torque change.

[0106] The formula for calculating the symmetry of the left / right turning torque variation is as follows:

[0107]

[0108] in, For the symmetry of the left / right turning torque variation, This represents the gradient value for the left-turn region. This represents the gradient value for the right-turn region. If... If it is too large, it will make people feel that the left and right directions are asymmetrical.

[0109] Reference Figure 5 The method of determining vehicle steering performance indicators based on the curve gradient and curve dispersion of each curve segment further includes:

[0110] Step S370: Subtract the gradient value of the median region from the evaluation gradient value of the left / right turning torque change.

[0111] Step S380: Calculate the ratio of the difference to the gradient value of the median region, and use it as the relative difference value between the median and non-median moment gradients.

[0112] Step S390: Calculate the arithmetic mean of the curve dispersion of each curve segment and use it as the torque fluctuation of the vehicle.

[0113] The formula for calculating the relative difference between the median and non-median moment gradients is as follows:

[0114]

[0115] in, The relative difference between the median and non-median moment gradients is given. This represents the gradient value in the median region. This is the evaluation gradient value for the change in left / right turning torque. If... If the value is large, the change in torque from the midpoint to the non-midpoint will appear unnatural; if... If the value is small, the non-midpoint torque gradient is large, and the steering force is heavy.

[0116] The formula for calculating the torque fluctuation of the vehicle is as follows:

[0117]

[0118] Where Δ1 is the dispersion of the first curve segment, Δ2 is the dispersion of the second curve segment, Δ3 is the dispersion of the third curve segment, Δ4 is ​​the dispersion of the fourth curve segment, Δ5 is the dispersion of the fifth curve segment, and Δ6 is the dispersion of the sixth curve segment. This represents the torque fluctuation of the vehicle; if this value is large, it will make the steering force feel uneven and have more jerks.

[0119] This invention also proposes a method for determining the softness or hardness of vehicle steering limit, the method comprising:

[0120] Obtain the vehicle's steering wheel angle and torque curve;

[0121] The steering wheel angle and torque curve within the preset limit range are fitted using a cubic polynomial.

[0122] Calculate the radius of curvature of the cubic polynomial fitted curve;

[0123] The stiffness or softness of the vehicle steering limit is determined based on the comparison between the radius of curvature value and the set value.

[0124] It should be noted that the steering wheel has rotation angle limits, namely left and right limit angles; see reference. Figure 7 The steering wheel is limited to approximately ±500°, and the torque within this limit range increases sharply with changes in angle. The driver will feel the steering wheel is difficult to turn. If the torque increases too rapidly within the limit range, the driver will feel the steering wheel suddenly stop rotating, lacking the sensation of torque increase, making the driver feel the vehicle's steering is too stiff. The preset limit range's angle range is determined by the R&D personnel based on the specific vehicle.

[0125] After fitting the steering wheel angle and torque curve within a preset limit range using a cubic polynomial, the radius of curvature of the fitted curve can be calculated based on the cubic polynomial, thereby determining the rate of change of torque within the limit range. (Refer to...) Figure 7 c1 represents the fitted curve for clockwise steering wheel rotation, and c2 represents the fitted curve for counterclockwise steering wheel rotation. The radii of curvature ρ1 and ρ2 of c1 and c2 are calculated using the radius of curvature calculation formula, where the radius of curvature formula is:

[0126]

[0127] Among them, y 1，2 Let ρ represent the cubic polynomials of curves c1 and c2, respectively. 1，2 Let represent the radii of curvature of curves c1 and c2, respectively.

[0128] Furthermore, the minimum radii of curvature for curves c1 and c2 are obtained:

[0129] ρ1，min =min(ρ1)

[0130] ρ 2，min =min(ρ2)

[0131] Where, ρ 1，min Let ρ be the minimum radius of curvature of curve c1. 2，min Let be the minimum radius of curvature of curve c2.

[0132] If ρ 1，min If the value is too small, it indicates that the limiting force changes significantly when turning clockwise, resulting in a stiffer steering limit.

[0133] If ρ 2，min If the value is too small, it indicates that the limiting force changes significantly when turning counterclockwise, resulting in a stiffer steering limit.

[0134] The minimum radius of curvature of c1 and c2 can be compared with a set value. If the minimum radius of curvature is greater than the set value, it means that the steering limit corresponding to the minimum radius of curvature is relatively stiff. The set value is determined by the R&D personnel.

[0135] The present invention also proposes a storage medium storing a vehicle steering performance index determination program, wherein when the vehicle steering performance index determination program is executed by a processor, the steps of the vehicle steering performance index determination method are implemented.

[0136] Alternatively, the storage medium stores a vehicle steering limit soft / hard judgment program, which, when executed by a processor, implements the steps of the vehicle steering limit soft / hard judgment method. The storage medium may include ROM, RAM, FLASH, floppy disk, CD, or DVD, etc.

[0137] The present invention also proposes an electronic device, which includes a processor and the aforementioned storage medium. The specific steps of the vehicle steering performance index determination program or the vehicle steering limit soft / hard judgment program stored in the storage medium are as described in the above embodiments. Since this electronic device adopts all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, and will not be elaborated further here.

[0138] The electronic device may be a vehicle controller, a vehicle steering detector, or a computer, etc.

[0139] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for determining vehicle steering performance indicators, characterized in that, The method for determining the vehicle steering performance index includes: Obtain the steering wheel angle and torque curve of the vehicle within a set steering angle range; The steering wheel angle and torque curve are segmented, and the curve gradient and curve dispersion of each segment are obtained. The vehicle steering performance indicators are determined based on the curve gradient and curve dispersion of each curve segment. The step of segmenting the steering wheel angle and torque curve includes: Based on the comparison between the steering wheel angle and the first and second set angles, the steering wheel angle and torque curve is divided into a left-turn region, a right-turn region, and a center region; wherein, the first set angle is smaller than the second set angle. Based on the positional relationship between the steering wheel angle and torque curve located in the left-turn area, right-turn area, and center area, the steering wheel angle and torque curve are divided into six segments. The determination of vehicle steering performance indicators based on the curve gradient and curve dispersion of each curve segment includes: Based on the curve gradients of the two curve segments in each region, determine their arithmetic mean and use it as the average gradient value of that region, thereby obtaining the gradient values ​​of the left-turn region, the right-turn region, and the median region. Obtain the difference and sum of the curve gradients of the two curve segments within each region; Calculate the ratio of the difference to the sum, and use the absolute value of this ratio as the gradient symmetry of the region where the corresponding curve is located, thereby obtaining the gradient symmetry of the left-turning region, the gradient symmetry of the right-turning region, and the gradient symmetry of the median region. The method of determining vehicle steering performance indicators based on the curve gradient and curve dispersion of each curve segment also includes: Based on the gradient values ​​of the left-turn and right-turn regions, their arithmetic mean is determined and used as the evaluation gradient value for the change in left / right turning torque. Obtain the difference and sum of the gradient values ​​in the left-turn region and the right-turn region; Calculate the ratio of the difference to the sum, and use the absolute value of this ratio as the symmetry of the left / right turning torque variation; The method of determining vehicle steering performance indicators based on the curve gradient and curve dispersion of each curve segment also includes: The difference between the gradient value of the median region and the evaluation gradient value of the left / right turning torque change is calculated. The ratio of the difference to the gradient value of the median region is calculated and used as the relative difference between the median and non-median moment gradients. Calculate the arithmetic mean of the curve dispersion of each segment and use it as the torque fluctuation of the vehicle.

2. The method for determining vehicle steering performance indicators as described in claim 1, characterized in that, The method of dividing the steering wheel angle and torque curve into a left-turn region, a right-turn region, and a center region based on the comparison between the steering wheel angle and a first set angle and a second set angle includes: If the steering wheel angle is less than or equal to the first set angle, then the steering wheel angle is divided into a left turn area; If the steering wheel angle is greater than the first set angle and less than or equal to the second set angle, then the steering wheel angle is divided into the middle region. If the steering wheel angle is greater than the second set angle, then the steering wheel angle is designated as a right turn zone.

3. The method for determining vehicle steering performance indicators as described in claim 1, characterized in that, The process of obtaining the curve gradient and curve dispersion of each curve segment includes: Obtain the dispersion of each curve segment; Each segment of the curve was fitted using a straight line; Obtain the slope value of the straight line corresponding to each curve segment, and use it as the curve gradient of that segment.

4. A method for determining the softness or hardness of vehicle steering limit, characterized in that, The method for determining the soft or hard nature of vehicle steering limit includes: Obtain the vehicle's steering wheel angle and torque curve; The steering wheel angle and torque curve within the preset limit range are fitted using a cubic polynomial. The radius of curvature of the cubic polynomial fitted curve is calculated using the formula for calculating the radius of curvature. The formula is as follows: ,in, Representing curves respectively and curve A cubic polynomial, Representing curves respectively and curve radius of curvature, curve The curve is the fitted curve for clockwise rotation of the steering wheel. The fitted curve for counter-clockwise rotation of the steering wheel; The stiffness or softness of the vehicle steering limit is determined based on the comparison between the radius of curvature value and the set value.

5. A storage medium, characterized in that, The storage medium stores a vehicle steering performance index determination program, which, when executed by a processor, implements the steps of the vehicle steering performance index determination method as described in any one of claims 1 to 3. Alternatively, the storage medium stores a vehicle steering limit soft / hard determination program, which, when executed by the processor, implements the steps of the vehicle steering limit soft / hard determination method as described in claim 4.

6. An electronic device, characterized in that, The electronic device includes a processor and a storage medium as described in claim 5.

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