A left-right assistance correction method based on a steering assistance system

Abstract

This invention discloses a method for correcting left and right power steering assist based on a power steering assist system, comprising: S1, providing left and right working conditions and a basic power steering assist table; S2, rapidly and alternately turning the steering wheel to the left and right, recording the assist torque in the left working condition and the assist torque in the right working condition respectively, obtaining the initial average value of left-side assist and the initial average value of right-side assist; S3, setting enabling conditions; S4, determining whether the vehicle meets the enabling conditions set in S3; S1 to S5 can monitor and calculate the average value of left and right assist in real time on the actual vehicle, improving the problem of poor real-time performance of traditional discrimination methods. If the left and right assist requirements are inconsistent during actual driving, the power steering assist torque in the basic power steering assist table is multiplied by an assist correction coefficient to automatically correct the assist value, improving the driver's driving experience and vehicle driving safety, and solving the technical problem of low calibration efficiency caused by the inability of traditional power steering assist correction methods to monitor and correct in real time.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology and relates to a method for correcting left and right steering assist based on a steering assist system. Background Technology

[0002] The steering system controls the lateral movement of a vehicle, affecting its handling stability, active safety, and driver comfort. Since commercial vehicle drivers are typically professional drivers who spend long hours driving, easy and comfortable vehicle control is crucial. With the gradual development of automotive technology, the energy required for the steering system has gradually shifted from being provided by the driver to being largely supplied by the engine or electric motor. The steering system has also evolved from traditional mechanical steering systems to power steering systems with assistance. Electric power steering (EPS) adds electronic control and actuators to the traditional mechanical steering system. By recognizing the torque and angle applied to the steering wheel by the driver, as well as inputs from other vehicle systems, it commands the steering motor to adjust the direction of the wheels to achieve steering control.

[0003] Traditional methods for determining whether the power assist required for left and right turns is consistent include: 1) On a test bench, directly inputting data such as steering wheel angle and hand torque to record curves showing the power assist demand on both sides when turning left and right; 2) On a real vehicle, maintaining the same test conditions to collect curves showing the power assist demand on both sides when turning left and right. However, both of these testing methods involve collecting the power assist demand curves for left and right turns separately under the same conditions and then comparing the consistency of the power assist on both sides. This approach has certain limitations. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a left and right power assist correction method based on a power steering system, thereby solving the technical problem of low calibration efficiency caused by the inability of traditional power assist correction methods to monitor and correct in real time.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A method for correcting left and right steering assist based on a power steering system includes the following steps:

[0007] S1, given the left working condition, right working condition, and steering base assist table;

[0008] The rotational speed in the left operating condition is positive; the rotational speed in the right operating condition is negative.

[0009] The steering basic assist table includes a steering basic assist table for the left working condition and a steering basic assist table for the right working condition.

[0010] S2, quickly turn the steering wheel alternately to the left and right, and record the assist torque in the left and right working conditions respectively to obtain the initial average value of the left assist. and the initial mean of the right-side assist

[0011] S3, set the enable conditions;

[0012] Enabling condition 1: Vehicle speed is within the first preset range;

[0013] Enabling condition two: The steering wheel angle is within the second preset range;

[0014] Enabling condition three: The hand torque is within the third preset range;

[0015] Enabling condition four: Steering wheel speed is within the fourth preset range;

[0016] Enabling condition five: Steering wheel speed, hand torque, and the direction of power assist demand are the same;

[0017] S4 determines whether the car meets the enabling conditions set in S3. If so, the maximum value and type of the required assistance within the corresponding time interval are obtained; otherwise, monitoring continues.

[0018] S5, determine the type of the maximum value of the demand assistance obtained from S4, and calculate the average value of the assistance on the left side respectively. and the right-side assist mean i∈[1,n] represents the number of times that condition S3 is satisfied;

[0019] S6, based on the left-side assist mean obtained from S5 and the right-side assist mean Calculate the sum M of the two, look up the sum threshold-assistance correction coefficient table based on the sum M to obtain the assist correction coefficient, and multiply the steering base assist torque in the left steering base assist table or the right steering base assist table given by S1 by the assist correction coefficient.

[0020] The threshold-assistance correction coefficient table represents the left-side assist mean. and the right-side assist mean The correspondence between the sum of and the assist correction coefficient, wherein the assist correction coefficient is a positive number.

[0021] This invention also includes the following technical features:

[0022] In S5, the average value of the left-side assist is calculated separately. and the right-side assist mean Specifically:

[0023] If the type of the maximum demand assistance obtained from S4 is determined to be the maximum assistance value on the left side... The mean value of the left-side assist is then calculated using the following formula. and the right-side assist mean

[0024]

[0025] If the type of the maximum demand assistance obtained from S4 is determined to be the maximum assistance value on the right side... The mean value of the left-side assist is then calculated using the following formula. and the right-side assist mean

[0026]

[0027] in:

[0028] Cof∈[0,1] is the weight coefficient.

[0029] In the S3, the steering wheel angle and hand torque are obtained through the angle torque sensor of the steering assist system, and the vehicle speed is obtained through the vehicle speed sensor of the steering assist system.

[0030] Compared with the prior art, the beneficial technical effects of this invention are:

[0031] In this invention, S1 to S5 enable real-time monitoring and calculation of the average value of left and right steering assist in actual vehicle operation, improving the problem of weak real-time performance of traditional discrimination methods. If the steering assist demand of the left and right sides is inconsistent during actual vehicle driving, S6 automatically corrects the steering assist value by multiplying the steering assist torque in the steering assist table by the assist correction coefficient, thereby improving the efficiency of calibration by technicians, the driving experience of drivers, and the safety of vehicle operation. This solves the technical problem of low calibration efficiency caused by the inability of traditional assist correction methods to monitor and correct in real time. Attached Figure Description

[0032] Figure 1 This is a flowchart of the present invention;

[0033] Figure 2 The value is the assist torque under normal operating conditions;

[0034] Figure 3 For steering wheel left turn working conditions;

[0035] Figure 4 For right steering wheel operation;

[0036] Figure 5 To select the time intervals for the steering wheel left-hand operation condition that meets the S3 enabling condition;

[0037] Figure 6 To select the time intervals for the steering wheel right turn operation that meet the S3 enabling condition;

[0038] Figure 7 To obtain the maximum assist value in each time interval under the left-hand working condition;

[0039] Figure 8 To obtain the maximum assist value in each time interval under the right-hand working condition;

[0040] Figure 9 To obtain the average value of the assistance from both the left and right sides and the sum of the assistance from both sides;

[0041] Figure 10 This refers to the operating condition where the assistance from both sides is inconsistent.

[0042] Figure 11 To assist in the revised operating conditions.

[0043] The specific content of the present invention will be further explained in detail below with reference to the embodiments. Detailed Implementation

[0044] It should be noted that, unless otherwise specified, all components in this invention are those known in the art.

[0045] The following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments. All equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0046] This invention provides a method for left and right assist correction based on a power steering system, comprising the following steps:

[0047] S1, given the left working condition, right working condition, and steering base assist table;

[0048] The speed is positive in the left operating condition; the speed is negative in the right operating condition.

[0049] The steering basic assist table includes a steering basic assist table for left-hand driving and a steering basic assist table for right-hand driving.

[0050] S2, quickly turn the steering wheel alternately to the left and right, and record the assist torque in the left and right working conditions respectively to obtain the initial average value of the left assist. and the initial mean of the right-side assist

[0051] S3, set the enable conditions;

[0052] Enabling condition 1: Vehicle speed is within the first preset range;

[0053] Enabling condition two: The steering wheel angle is within the second preset range;

[0054] Enabling condition three: The hand torque is within the third preset range;

[0055] Enabling condition four: Steering wheel speed is within the fourth preset range;

[0056] Enabling condition five: Steering wheel speed, hand torque, and the direction of power assist demand are the same;

[0057] S4 determines whether the car meets the enabling conditions set in S3. If so, the maximum value and type of the required assistance within the corresponding time interval are obtained; otherwise, monitoring continues.

[0058] S5, determine the type of the maximum value of the demand assistance obtained from S4, and calculate the average value of the assistance on the left side respectively. and the right-side assist mean i∈[1,n] represents the number of times that condition S3 is satisfied;

[0059] S6, based on the left-side assist mean obtained from S5 and the right-side assist mean Calculate the sum M of the two, look up the sum threshold-assistance correction coefficient table based on the sum M to obtain the assist correction coefficient, and multiply the steering base assist torque in the left steering base assist table or the right steering base assist table given by S1 by the assist correction coefficient.

[0060] The threshold-assistance correction coefficient table represents the mean assist value on the left. and the right-side assist mean The relationship between the sum and the assist correction factor, where the assist correction factor is a positive number.

[0061] In the above technical solution, S1 to S5 can monitor and calculate the average value of left and right assist in real time on the actual vehicle, which improves the problem of poor real-time performance of traditional discrimination methods. If the left and right assist needs are inconsistent during actual vehicle driving, S6 can automatically correct the assist value by multiplying the steering base assist torque in the steering base assist table by the assist correction coefficient, thereby improving the efficiency of calibration by technicians, as well as the driving experience of drivers and the safety of vehicle driving. This solves the technical problem of low calibration efficiency caused by the inability of traditional assist correction methods to monitor and correct in real time in the existing technology.

[0062] In S2, the initial average value of the left and right assist can be determined as follows: At a low vehicle speed, quickly and alternately turn the steering wheel to the left and right, obtaining the assist curves for both sides. Within the range where the assist value appears most frequently, select a value as the initial average assist value. For example... Figure 2 As shown. Figure 2The orange line represents the assist torque curve, the blue and yellow lines represent the average assist torque on the left and right sides respectively, the purple line represents the difference between the average assist torque on both sides, and the green line indicates the point where the assist torque on the left and right sides is inconsistent. Under normal operating conditions, the assist torque on both sides is basically symmetrical, and the difference is small. If... Figure 2 For example, the initial average value of the assist can be taken as ±3Nm.

[0063] In S1, when the steering wheel is turned left or right, the power assist torque is distinguished according to the different directions of left and right steering, which is used in subsequent steps to calculate the average power assist value in the left and right directions respectively. For example... Figures 3 to 4 As shown, the green line represents the steering wheel angle signal, the blue line indicates left steering, and the orange line indicates right steering.

[0064] like Figures 5 to 6 As shown, the green line represents the steering wheel angle signal, the blue line represents the time interval selected under the condition of steering wheel left turn in S2 that meets the enabling conditions, and the orange line represents the time interval selected under the condition of steering wheel right turn in S2 that meets the enabling conditions. The maximum assist value of each interval is extracted in preparation.

[0065] like Figures 7 to 8 The figure shows the maximum assist value for each time interval under the left and right working conditions;

[0066] like Figure 9 In the graph, the red line represents the required torque, the blue line represents the average assist value on the left side, the yellow line represents the average assist value on the right side, and the purple line represents the difference in assist values ​​between the two sides.

[0067] like Figure 10 The orange line represents the assist torque curve. At the beginning, there is a significant inconsistency between the left and right assist torques. The difference between the average assist torque values ​​of the two sides (purple line) calculated by the method in this paper is relatively large, and the marker position (green line) indicating the inconsistency between the left and right assist torques is set.

[0068] In S6, such as Figure 11 The orange line shows the assist torque curve. Initially, there is a significant inconsistency between the left and right assist torques. The difference in the average assist torque between the two sides (purple line) calculated using the method presented in this paper is relatively large, and the indicator (green line) for the inconsistency between the left and right assist torques is set. At this point, the basic steering assist torque in the basic steering assist table is multiplied by an assist correction coefficient to correct the assist value. When turning the steering wheel to the right, the basic assist table is multiplied by the coefficient to appropriately amplify the motor assist. It can be seen that the assist on the right side increases, the difference between it and the assist on the left side decreases, and the difference in assist torque between the two sides also decreases. This achieves the function of detecting and correcting torque when the assist torques on the left and right sides are inconsistent, based on actual vehicle testing.

[0069] In S6, the threshold-assistance correction coefficient table is shown in Table 1;

[0070] Table 1

[0071] Assist correction coefficient 0.25 0.5 0.8 1 1.2 1.5 4

[0072] In S5, the average value of the left-side assist is calculated separately. and the right-side assist mean Specifically:

[0073] If the type of the maximum demand assistance obtained from S4 is determined to be the maximum assistance value on the left side... The mean value of the left-side assist is then calculated using the following formula. and the right-side assist mean

[0074]

[0075] If the type of the maximum demand assistance obtained from S4 is determined to be the maximum assistance value on the right side... The mean value of the left-side assist is then calculated using the following formula. and the right-side assist mean

[0076]

[0077] in:

[0078] Cof∈[0,1] is the weight coefficient.

[0079] In the S3, the steering wheel angle and hand torque are obtained through the angle torque sensor of the steering assist system, and the vehicle speed is obtained through the vehicle speed sensor of the steering assist system.

Claims

1. A method for correcting left and right steering assist based on a power steering system, characterized in that, Includes the following steps: S1, given the left working condition, right working condition, and steering base assist table; The rotational speed in the left operating condition is positive; the rotational speed in the right operating condition is negative. The steering basic assist table includes a steering basic assist table for the left working condition and a steering basic assist table for the right working condition. S2, quickly turn the steering wheel alternately to the left and right, and record the assist torque in the left and right working conditions respectively to obtain the initial average value of the left assist. and the initial mean of the right-side assist S3, set the enable conditions; Enabling condition 1: Vehicle speed is within the first preset range; Enabling condition two: The steering wheel angle is within the second preset range; Enabling condition three: The hand torque is within the third preset range; Enabling condition four: Steering wheel speed is within the fourth preset range; Enabling condition five: Steering wheel speed, hand torque, and the direction of power assist demand are the same; S4 determines whether the car meets the enabling conditions set in S3. If so, the maximum value and type of the required assistance within the corresponding time interval are obtained; otherwise, monitoring continues. S5, determine the type of the maximum value of the demand assistance obtained from S4, and calculate the average value of the assistance on the left side respectively. and the right-side assist mean i∈[1,n] represents the number of times that condition S3 is satisfied; S6, based on the left-side assist mean obtained from S5 and the right-side assist mean Calculate the sum M of the two, look up the sum threshold-assistance correction coefficient table based on the sum M to obtain the assist correction coefficient, and multiply the steering base assist torque in the left steering base assist table or the right steering base assist table given by S1 by the assist correction coefficient. The threshold-assistance correction coefficient table represents the left-side assist mean. and the right-side assist mean The correspondence between the sum of and the assist correction coefficient, wherein the assist correction coefficient is a positive number.

2. The left and right assist correction method based on a steering assist system as described in claim 1, characterized in that, In S5, the average value of the left-side assist is calculated separately. and the right-side assist mean Specifically: If the type of the maximum demand assistance obtained from S4 is determined to be the maximum assistance value on the left side... The mean value of the left-side assist is then calculated using the following formula. and the right-side assist mean If the type of the maximum demand assistance obtained from S4 is determined to be the maximum assistance value on the right side... The mean value of the left-side assist is then calculated using the following formula. and the right-side assist mean in: Cof∈[0,1] is the weight coefficient.

3. The left and right assist correction method based on a steering assist system as described in claim 1, characterized in that, In the S3, the steering wheel angle and hand torque are obtained through the angle torque sensor of the steering assist system, and the vehicle speed is obtained through the vehicle speed sensor of the steering assist system.

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