Accelerator pedal calibration method

Abstract

A throttle pedal calibration method is used to calibrate the corresponding relationship between the throttle pedal and the acceleration driving force and the deceleration braking force in a single-pedal mode. On the basis of linear calibration of the throttle pedal opening, the acceleration driving force and the deceleration braking force, a correction parameter related to the throttle pedal opening change rate is introduced. When the throttle pedal opening change rate is fast, a stronger acceleration driving force or deceleration braking force is provided. The present invention enables the vehicle's dynamic response to better meet the driver's expectations, improves the driving experience, and improves driving safety.

Description

Technical Field

[0001] The invention belongs to a vehicle control method, and in particular relates to an accelerator pedal calibration method. Background Art

[0002] With the rapid development of electrification in the automotive industry, various types of electric vehicles are increasingly being used in production and life. The working mode of the drive and braking system of electric vehicles is quite different from that of traditional vehicles, which makes their control methods also different. For example, electric logistics vehicles and electric forklifts have already applied the single-pedal control method, and the driver controls the acceleration and deceleration of the vehicle by stepping on the accelerator pedal. As the market size of household electric vehicles continues to expand, more and more manufacturers have begun to apply the single-pedal mode to household electric vehicles equipped with kinetic energy recovery functions. However, the existing technology often uses a single parameter, the accelerator pedal opening, to control acceleration and deceleration. When the user intends to accelerate or decelerate urgently, it cannot accurately judge the user's expectations, which affects the driving experience and its safety needs to be improved. Summary of the invention

[0003] The inventors have realized that, compared with the travel opening of the accelerator pedal, the rate of change of the accelerator pedal can better reflect the driver's true intention: the faster the accelerator pedal is pressed down, the more urgent the acceleration demand is; the faster the accelerator pedal is lifted up, the more urgent the deceleration demand is.

[0004] The purpose of the present invention is to provide an accelerator pedal calibration method, which can correct the acceleration driving force and deceleration braking force of a vehicle according to the change rate of the accelerator pedal opening, so that it can better meet the driver's expectations, improve the driving experience, and enhance driving safety.

[0005] According to one aspect of an embodiment of the present invention, a method for calibrating an accelerator pedal is provided, which establishes a corresponding relationship between an accelerator pedal motion parameter and a vehicle driving force and a braking force, comprising the following steps:

[0006] a) Taking the accelerator pedal opening when the vehicle is stationary or traveling at a constant speed as zero, calibrate the corresponding relationship between the opening change caused by pressing / lifting the accelerator pedal and the acceleration driving force F1 / deceleration braking force F2 according to the linear relationship, and use this as the basic corresponding relationship;

[0007] b) setting a correction parameter a, wherein the correction parameter a is positively correlated with the rate of change of the throttle pedal opening within at least one numerical interval;

[0008] c) using the correction parameter a to correct the basic corresponding relationship, and to perform correction calculation on the actual acceleration driving force f1 and the actual deceleration braking force f2, wherein f1 = aF1, f2 = aF2.

[0009] The calibration method allows the vehicle to correct the braking and acceleration effects according to the speed at which the driver presses or releases the pedal during braking and acceleration, so that they meet the driver's expectations.

[0010] Furthermore, the step b) also includes determining a correction parameter table, wherein the correction parameter table includes values ​​of the correction parameter a corresponding to different accelerator pedal opening change rates, and the correction parameter table is determined by actual vehicle acceleration and braking tests under predetermined load weight and test conditions.

[0011] Furthermore, the correction parameter a has a value range of 1≤a≤2, and when the accelerator pedal opening rate of change is less than a set value, a=1

[0012] Furthermore, for a vehicle traveling at a constant speed, the accelerator pedal opening is provided with a constant speed opening interval (-i, i), and when the accelerator pedal opening variation range is within the constant speed opening interval, no acceleration driving force and deceleration braking force are generated.

[0013] Furthermore, the rate of change of the accelerator pedal opening in step b) is determined by measuring the time Δt taken for the accelerator pedal to leave the constant speed opening interval from the zero position opening.

[0014] Furthermore, when the accelerator pedal opening stays at any non-zero position in the constant speed opening range for more than a critical time, the current opening is reset to a new zero position. Automatically resetting the zero position can prevent risks caused by bumps or misoperation.

[0015] Furthermore, the setting value of the accelerator pedal opening change rate is the accelerator pedal opening change rate when Δt=critical time.

[0016] Furthermore, the critical time has a value range of 0.1s≤critical time≤5s.

[0017] Preferably, different correction parameter tables are measured for different load conditions of the same vehicle model, so as to allow the driver to select automatically or manually. The driver sets the correction parameters according to his driving habits and riding experience to further improve the driving experience.

[0018] Preferably, the driver is allowed to select and set the value of the critical time or the constant speed opening range. The driver can set the sensitivity of the accelerator pedal according to actual needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flowchart diagram of an embodiment of a throttle calibration method.

[0020] The purpose of the above drawings is to explain the technical concept of the present invention in detail so as to facilitate understanding by those skilled in the art, and is not intended to limit the implementation of the present invention. DETAILED DESCRIPTION

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0022] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0023] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the techniques, methods and equipment should be considered as part of the specification.

[0024] Although the terms used in this application are selected from well-known and commonly used terms, some of the terms mentioned in this application specification may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.

[0025] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0026] According to an embodiment of the present invention, a method for calibrating an accelerator pedal is provided, and the process is as follows:

[0027] a) Calibrate the basic relationship between the accelerator pedal opening and vehicle power. When the vehicle is stationary, the accelerator pedal is at the minimum depression stroke; when the vehicle is traveling at a constant speed at different speeds, the accelerator pedal is at different depression stroke openings. The accelerator pedal opening at this stationary or constant speed is used as the zero position of the accelerator pedal opening at the corresponding driving speed, and the accelerator pedal constant speed opening interval (-i, i) is set. The constant speed opening interval is a range that allows the accelerator pedal to move slightly without changing the vehicle's power state. When the accelerator pedal moves out of this range, the vehicle's power system begins to intervene. Positive numbers in the interval (-i, i) indicate an increase in the accelerator pedal opening, and negative numbers indicate a decrease in the accelerator pedal opening. When the accelerator pedal opening exceeds i, the power system provides additional driving force for the vehicle; when the accelerator pedal opening is less than i, the power system provides braking force for the vehicle. The acceleration driving force F1 and the deceleration braking force F2 are linearly corresponding to the accelerator pedal opening x, respectively. This calibrated linear correspondence is the basic correspondence. As Figure 1 As shown in step 1, F1=K1x, F2=K2x, where K1 and K2 are calibrated proportional coefficients.

[0028] b) Set the correction parameter a, the value range of a is 1-2. Set the time taken for the accelerator pedal to move from zero position to leave the constant speed opening range as △t. When △t is less than a specific value t, y is negatively correlated with △t. Two examples of specific corresponding relationships are shown in Table 1 and Table 2. Table 1 and Table 2 are determined through acceleration and braking tests of real vehicles combined with the riding experience of different test occupants. The optional range of t is 0.1s-5s. Figure 1 As shown in step 2.

[0029] △t / s 0.01 0.02 0.04 0.06 0.1 0.2 0.4 … 5 a 1.1 1.09 1.085 1.08 1.078 1.075 1.073 … 1

[0030] Table 1 Acceleration driving force correction parameter table (t = 5s)

[0031] △t / s 0.01 0.02 0.04 0.06 0.1 0.2 0.4 … 5 a 2 1.5 1.1 1.09 1.08 1.075 1.073 … 1

[0032] Table 2 Acceleration driving force correction parameter table (t = 5s)

[0033] c) Correct the actual output based on △t. Establish the correction relationship between the additional driving force f1 and braking force f2 of the actual output of the power system: f1 = yF1, f2 = yF2. Figure 1 As shown in step 3.

[0034] d) Set the critical time to 5s. When the accelerator pedal stays at a certain position within the constant speed opening range for more than 5s, the position is reset to zero. Figure 1 As shown in step 4.

[0035] The accelerator pedal calibration method provided by the present invention can correct the acceleration driving force and deceleration braking force of the vehicle according to the change rate of the accelerator pedal opening, so that it better meets the driver's expectations, improves the driving experience, and enhances driving safety.

[0036] In other embodiments, the value of a in the correction parameter table can also be obtained through simulation calculation. The selection of the correction parameter a has a certain relationship with the vehicle weight, passenger load, chassis hardness, center height and tire condition. The basic principle of its selection is to quickly respond to the driver's intention while maintaining a good riding experience.

[0037] 1≤a≤2 is a preferred value range for theoretically maintaining a good riding experience, and the values ​​of the correction parameters in other embodiments are not limited thereto.

[0038] The purpose of setting the constant speed opening interval is to avoid sudden acceleration or deceleration of the vehicle due to rapid and small changes in the accelerator pedal opening caused by bumps or misoperation. This setting is not necessary in embodiments where the value of a is small.

[0039] In other embodiments, the linear velocity or angular velocity of the instantaneous movement of the accelerator pedal may be measured, and correction parameters may be introduced to correct the acceleration driving force and the braking deceleration force during the entire process of the accelerator pedal movement.

[0040] The purpose of setting the critical time for resetting the zero position opening is to maintain the consistency of the acceleration and braking operation feeling during driving, and to avoid that a small change in the accelerator pedal during driving affects the response process of the acceleration and braking correction. The value of the critical time affects the sensitivity of the correction response during driving. In some embodiments, the setting of the critical time is not necessary.

[0041] In some embodiments, different correction parameter tables can be measured according to different vehicle load conditions, such as one passenger and five passengers. During driving, different correction parameters can be selected and set by detecting the vehicle load or by manual selection by the driver to obtain a better driving experience. It should be understood that in some embodiments, the main technical purpose of the present invention can also be achieved without measuring multiple sets of correction parameter tables.

[0042] Similarly, in some embodiments, the range of the critical time or the constant speed opening interval can be set, and then the sensitivity of the accelerator pedal correction response can be set to meet the needs of different drivers. Similarly, setting the range of the critical time or the constant speed opening interval is a preferred but not necessary step of the embodiment of the present invention.

[0043] It should be understood that the purpose of the above embodiments is to describe the present invention in detail so that those skilled in the art can understand the technical concept of the present invention, rather than to limit the implementation of the present invention. Within the scope of protection of the claims of the present invention, any improvement or equivalent replacement of the parts, devices or method steps involved, as well as the combination of different embodiments without conflict, fall within the scope of protection of the present invention.

Claims

1. A method for calibrating an accelerator pedal, establishing a corresponding relationship between accelerator pedal motion parameters and vehicle driving force and braking force, characterized in that: The following steps are involved: a) The accelerator pedal opening when the vehicle is stationary or traveling at a constant speed at different speeds is taken as zero position, and the corresponding relationship between the opening change caused by pressing / lifting the accelerator pedal and the acceleration driving force F1 / deceleration braking force F2 is calibrated according to the linear relationship, and this is used as the basic corresponding relationship; for a vehicle traveling at a constant speed, the accelerator pedal opening is provided with a constant speed opening interval (-i, i), when the accelerator pedal opening variation range is within the constant speed opening interval, no acceleration driving force and deceleration braking force are generated, when the accelerator pedal opening stays at any non-zero position opening position within the constant speed opening interval for more than a critical time, the current opening is reset to a new zero position opening; b) setting a correction parameter a, wherein the correction parameter a is positively correlated with the rate of change of the accelerator pedal opening within at least one numerical interval; c) using the correction parameter a to correct the basic corresponding relationship, and to perform correction calculation on the actual acceleration driving force f1 and the actual deceleration braking force f2, wherein f1 = aF1, f2 = aF2.

2. The calibration method according to claim 1, characterized in that: The step b) also includes determining a correction parameter table, which includes values ​​of the correction parameter a corresponding to different accelerator pedal opening change rates, and the correction parameter table is determined by actual vehicle acceleration and braking tests under predetermined load weight and test conditions.

3. The calibration method according to claim 2, characterized in that: The correction parameter a has a value range of 1≤a≤2, and when the accelerator pedal opening change rate is less than a set value, a=1.

4. The calibration method according to claim 1, characterized in that: The rate of change of the accelerator pedal opening in step b) is determined by measuring the time Δt taken for the accelerator pedal to leave the constant speed opening interval from the zero position opening.

5. The calibration method according to claim 1, characterized in that: The setting value of the accelerator pedal opening change rate is the accelerator pedal opening change rate when Δt=critical time.

6. The calibration method according to claim 1, characterized in that: The critical time has a value range of 0.1s≤critical time≤5s.

7. The calibration method according to claim 2, characterized in that: For different load conditions of the same vehicle model, different correction parameter tables are measured respectively to allow the driver to select automatically or manually.

8. The calibration method according to claim 6, characterized in that: Allow the driver to select and set the value of the critical time or constant speed opening range.

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