Self-adaptive braking method and system with adjustable deceleration

Abstract

The invention discloses a deceleration-adjustable self-adaptive braking method and system, and belongs to the field of vehicle braking. The method includes: establishing driving conditions according to driving habits of a driver; for each driving working condition, judging whether the driver has the intention of adjusting the braking deceleration or not under the corresponding working condition; when the driver has the intention of adjusting the braking deceleration, the actual deceleration of different pedal strokes under the corresponding working conditions is obtained, and the expected deceleration of the corresponding pedal stroke is calculated; according to the expected deceleration, the motor driving torque of the expected deceleration is reversely deduced by combining the whole vehicle parameters, and a relation curve of the pedal travel and the motor driving torque under the corresponding working condition is fitted; and when the driver implements the pedal travel under the corresponding working condition, the whole vehicle braking system outputs the corresponding motor driving torque to control the output of the actual deceleration according to the relation curve of the pedal travel under the corresponding working condition and the motor driving torque. The braking deceleration output can be adaptively adjusted according to the driving habit of a driver.

Description

Technical Field

[0001] The invention belongs to the field of vehicle braking, and in particular relates to an adaptive braking method and system with adjustable deceleration. Background Art

[0002] With the rapid development of intelligent driving technology, adaptive braking systems can use sensors (such as radars, cameras, etc.) to monitor driving information and surrounding environment in real time, and combine key information such as the driver's deceleration requirements, the following distance to the vehicle in front, and the driving route to predict potential collision risks. They can also increase braking force input through hydraulic brake units or wire-controlled brake units to ensure that the vehicle can brake quickly and accurately in emergency braking situations, thereby avoiding collisions or reducing the severity of collisions.

[0003] The comparative document (CN114919548A) discloses an adaptive braking control method based on millimeter wave radar, which belongs to the field of vehicle intelligent technology, including the first step: judging whether the reverse lateral braking function is activated; the second step: detecting the moving target in the RCTB action area of ​​the driving vehicle through the millimeter wave radar. If the moving target meets the collision conditions with the driving vehicle, the RCTB system issues an emergency braking and alarm command, and adopts a corresponding adaptive deceleration strategy. Through the detection and tracking of objects behind the vehicle by millimeter waves, referring to the daily use scenarios of the vehicle and combining with the ENCAP standard, a high-risk obstacle recognition and judgment algorithm and strategy are designed, which can effectively judge high-risk collision targets from the rear; and according to the motion state of the vehicle and the target, the vehicle is controlled to perform adaptive braking, which effectively avoids collisions while improving the comfort of the driver, greatly improving the driving safety and driving experience of the vehicle.

[0004] However, like most existing technologies, the adaptive braking system of the above-mentioned reference document is currently mainly used in working conditions where there is a risk of collision, and has no application in conventional braking of the driver. Summary of the invention

[0005] The present invention aims to overcome the shortcomings of the prior art and proposes an adaptive braking method and system with adjustable deceleration, so as to achieve the purpose of adaptively adjusting the braking deceleration output according to the driver's driving habits, so as to meet the comfortable braking needs of different drivers, and the user's commonly used braking driving data information can be migrated to the new car, shortening the user's adaptation time to the vehicle.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] An adaptive braking method with adjustable deceleration, the method comprising the following steps:

[0008] Step S1, establishing multiple driving conditions according to the driver's driving habits;

[0009] Step S2: for each driving condition, determining whether the driver intends to adjust the braking deceleration under the corresponding condition;

[0010] Step S3: when the driver intends to adjust the braking deceleration, the actual deceleration of different pedal strokes under the corresponding working conditions is obtained, and the expected deceleration of the corresponding pedal stroke is calculated;

[0011] Step S4, according to the expected deceleration, in combination with the vehicle parameters, the motor driving torque corresponding to the expected deceleration is inferred, and finally a relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition is fitted;

[0012] Step S5: When the driver implements the pedal stroke under the corresponding working condition, according to the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition, the vehicle braking system outputs the corresponding motor driving torque to control the output of the actual deceleration.

[0013] Preferably, the step S1 comprises:

[0014] Step S11, when it is detected that the driver has applied braking, corresponding vehicle status data is recorded, including the vehicle speed at the start of braking, the distance to other vehicles following the vehicle or obstacles, the steering wheel angle, and the gradient of the change in the brake pedal travel; multiple vehicle status data constitute a vehicle status data set;

[0015] Step S12: Divide the vehicle state data set according to a preset range to obtain segmented vehicle state data sets in different data ranges, each segmented vehicle state data set corresponding to a driving condition label.

[0016] Preferably, before step S2, the method further includes: when it is detected that the driver brakes, determining whether the current driving condition exists; when the current driving condition exists, continuing to execute step S2; when the current driving condition does not exist, establishing a driving condition label separately for the vehicle status data under the current driving condition, and continuing to execute step S2.

[0017] Preferably, in step S2, whether the driver intends to adjust the braking deceleration is determined by the pedal stroke change amount and the pedal stroke change gradient between the current sampling point and the previous sampling point; the determination conditions for whether the driver intends to adjust the braking deceleration are as follows:

[0018] (1) The pedal stroke change is greater than a set first change threshold and the pedal stroke change is less than a set second change threshold, wherein the first change threshold is less than the second change threshold;

[0019] (2) the pedal stroke change gradient is greater than a set first change gradient threshold and the pedal stroke change gradient is less than a set second change gradient threshold, wherein the first change gradient threshold is less than the second change gradient threshold;

[0020] When (1) and (2) are satisfied at the same time, it means that the driver intends to adjust the braking deceleration; otherwise, it means that the driver has no intention to adjust the braking deceleration or has an intention to perform emergency braking; when the pedal stroke becomes smaller and the pedal stroke change gradient is negative, the driver expects to reduce the braking deceleration; when the pedal stroke becomes larger and the pedal stroke change gradient is positive, the driver expects to increase the braking deceleration.

[0021] Preferably, in step 2, the driving conditions of emergency braking and auxiliary braking are also filtered, that is, when any of the following driving conditions occurs, the corresponding driving condition is excluded: the pedal stroke is greater than the set stroke threshold; the pedal stroke change gradient is greater than the set second change gradient threshold; the vehicle deceleration is greater than the set deceleration threshold; the anti-lock braking system is activated; the brake assist system is activated.

[0022] Preferably, in step S3, when the driver intends to adjust the braking deceleration, the deceleration and pedal travel at the current time t and the previous time t-1 are obtained, a t and a t-1 They correspond to the deceleration at the current time t and the previous time t-1 respectively; s t and t-1 They correspond to the pedal travel at the current time t and the previous time t-1 respectively; where a t-1 That is, the pedal travel s under the current driving condition t-1 The actual deceleration; then the pedal travel s under the current driving condition t-1 The expected deceleration is Min(a t-1 ±0.1m / s 2 , (a t +a t-1 ) / 2), where Min(a t-1 -0.1m / s 2 , (a t +a t-1 ) / 2) indicates that the driver expects to reduce deceleration, Min(a t-1 +0.1m / s 2 , (a t +a t-1 ) / 2) indicates that the driver expects to increase the deceleration.

[0023] Preferably, before step S5, the method further comprises repeatedly executing steps S2 to S4, and continuously iteratively updating the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition.

[0024] Preferably, in step S4, the method further includes storing a relationship curve between the pedal stroke and the motor driving torque under corresponding working conditions in a cloud server for data migration when the vehicle is replaced.

[0025] Preferably, when performing data migration, the cloud server stores the relationship curve between the pedal stroke and the motor driving torque under the corresponding working conditions. Therefore, the motor driving torque is first converted into the expected deceleration according to the whole vehicle parameters of the original vehicle, and the relationship curve between the pedal stroke and the expected deceleration under different driving conditions is obtained. Then, the relationship curve between the pedal stroke and the motor driving torque of the new car is obtained by reverse deduction according to the whole vehicle parameters of the new car.

[0026] At the same time, the present application also proposes an adaptive braking system with adjustable deceleration, which is configured according to the above-mentioned adaptive braking method with adjustable deceleration, and includes a sensor unit, a controller, and a braking unit, wherein the controller is connected to the sensor unit and the braking unit, respectively; the sensor unit is used to collect vehicle status data and send it to the controller; the controller is used to process the vehicle status data according to the above-mentioned adaptive braking method with adjustable deceleration so as to adjust the motor driving torque output by the braking unit to control the output of the actual deceleration.

[0027] The technical effect of the present invention is as follows: the present application identifies the driver's intention to adjust the braking deceleration, combines the actual output deceleration corresponding to the pedal stroke, adjusts the motor driving torque output by the vehicle's braking system, and makes the actual output deceleration continuously approach the expected deceleration, thereby achieving the purpose of adaptively adjusting the braking deceleration output according to the driver's driving habits, so as to meet the comfortable braking needs of different drivers, and the user's commonly used braking driving data information can be migrated to the new car, shortening the user's adaptation time to the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The present invention is a flowchart of an adaptive braking method with adjustable deceleration according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The following is a further detailed description of the specific implementation of the present invention through the description of the embodiments with reference to the accompanying drawings, the purpose of which is to help those skilled in the art have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention, and to facilitate its implementation. It should be noted that the words "first", "second" and the like described in this application are only for the convenience of describing the technical solution to distinguish different components, and are not used to limit this application. In order to make the technical solution of the present invention clearer, the present invention is explained through the following embodiments.

[0030] The present application proposes an adaptive braking method with adjustable deceleration, the method comprising the following steps:

[0031] Step S1, establishing multiple driving conditions according to the driver's driving habits;

[0032] Step S2: for each driving condition, determining whether the driver intends to adjust the braking deceleration under the corresponding condition;

[0033] Step S3: when the driver intends to adjust the braking deceleration, the actual deceleration of different pedal strokes under the corresponding working conditions is obtained, and the expected deceleration of the corresponding pedal stroke is calculated;

[0034] Step S4, according to the expected deceleration, in combination with the vehicle parameters, the motor driving torque corresponding to the expected deceleration is inferred, and finally a relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition is fitted;

[0035] Step S5: When the driver implements the pedal stroke under the corresponding working condition, according to the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition, the vehicle braking system outputs the corresponding motor driving torque to control the output of the actual deceleration.

[0036] Below, this embodiment combines Figure 1 The flowchart shown is described in detail.

[0037] Step S1: Establish multiple driving conditions according to the driver's driving habits. Specifically, step S1 includes:

[0038] Step S11: When it is detected that the driver has applied the brakes, the corresponding vehicle status data is recorded, including the vehicle speed at the start of braking, the distance of other vehicles following the vehicle or obstacles, the steering wheel angle, and the gradient of the brake pedal stroke change. In this embodiment, the wheel speed sensor collects the vehicle speed; the radar and camera collect the distance of other vehicles following the vehicle or obstacles; the pedal stroke displacement sensor collects the brake pedal stroke change and gradient; the steering wheel angle sensor collects the steering wheel angle and other information to record the vehicle status data, which often corresponds to the driver's driving habits. Multiple vehicle status data constitute the vehicle status data set.

[0039] Step S12: Divide the vehicle state data set according to a preset range to obtain segmented vehicle state data sets in different data ranges, each segmented vehicle state data set corresponds to a driving condition label, and each driving condition label can represent a driving habit of a driver.

[0040] Since the driver's driving habits may change, the Sog driving condition established in step S1 may not cover all situations. Therefore, before step S2, the adaptive braking method of this embodiment further includes: when the driver's braking is detected, determining whether the current driving condition exists; when the current driving condition exists, continuing to execute step S2; when the current driving condition does not exist, establishing a driving condition label for the vehicle state data under the current driving condition, and continuing to execute step S2. In this way, the driving conditions are continuously expanded to cover more driving habits.

[0041] Step S2: for each driving condition, determine whether the driver intends to adjust the braking deceleration under the corresponding condition.

[0042] Specifically, step S2 of this embodiment includes: judging whether the driver intends to adjust the braking deceleration by the pedal stroke change amount and the pedal stroke change gradient between the current sampling point and the previous sampling point; the judging condition of whether the driver intends to adjust the braking deceleration is as follows:

[0043] (1) The pedal stroke change is greater than a set first change threshold and is less than a set second change threshold, wherein the first change threshold is less than the second change threshold; in this embodiment, the total pedal stroke is 100 mm, the first change threshold can be set to ±2 mm, and the second change threshold can be set to ±15 mm.

[0044] (2) The pedal stroke change gradient is greater than a set first change gradient threshold and the pedal stroke change gradient is less than a set second change gradient threshold, wherein the first change gradient threshold is less than the second change gradient threshold; in this embodiment, the total pedal stroke is 100 mm, the first change gradient threshold can be set to 1 mm / s, and the second change gradient threshold can be set to 250 mm / s.

[0045] When (1) and (2) are satisfied at the same time, it means that the driver intends to adjust the braking deceleration; otherwise, it means that the driver has no intention to adjust the braking deceleration or has an intention to perform emergency braking; when the pedal stroke becomes smaller and the pedal stroke change gradient is negative, the driver expects to reduce the braking deceleration; when the pedal stroke becomes larger and the pedal stroke change gradient is positive, the driver expects to increase the braking deceleration.

[0046] In actual driving, the driver may cause emergency braking and auxiliary braking due to reasons such as obstacle avoidance, but this situation is sporadic and has a very low probability of occurring under normal braking conditions. Therefore, before step 2, this embodiment also filters the driving conditions of emergency braking and auxiliary braking, that is, when any of the following driving conditions occurs, the corresponding driving condition is excluded: the pedal stroke is greater than the set stroke threshold (in this embodiment, the total pedal stroke is 100mm, and the corresponding stroke threshold can be set to 80mm); the pedal stroke change gradient is greater than the set second change gradient threshold (250mm / s in this embodiment); the vehicle deceleration is greater than the set deceleration threshold; the anti-lock braking system is activated; the brake assist system is activated.

[0047] Step S3: When the driver intends to adjust the braking deceleration, the actual deceleration of different pedal strokes under the corresponding working conditions is obtained, and the expected deceleration of the corresponding pedal stroke is calculated.

[0048] Specifically, in step S3, when the driver intends to adjust the braking deceleration, the deceleration and pedal travel at the current time t and the previous time t-1 are obtained. The deceleration can be acquired by the IMU (inertial measurement unit) combined sensor. t and a t-1 They correspond to the deceleration at the current time t and the previous time t-1 respectively; s t and t-1 They correspond to the pedal travel at the current time t and the previous time t-1 respectively; where a t-1 That is, the pedal travel s under the current driving condition t-1 The actual deceleration; then the pedal travel s under the current driving condition t-1 The expected deceleration is Min(a t-1 ±0.1m / s 2 , (a t +a t-1 ) / 2), where Min(a t-1 -0.1m / s 2 , (a t +a t-1 ) / 2) indicates that the driver expects to reduce deceleration, Min(a t-1 +0.1m / s 2 , (a t +a t-1 ) / 2) indicates that the driver expects to increase the deceleration.

[0049] Step S4, according to the expected deceleration, combined with the vehicle parameters (such as pedal characteristic parameters, etc.), the motor drive torque corresponding to the expected deceleration is inferred, and finally the relationship curve between the pedal stroke and the motor drive torque under the corresponding working condition is fitted. The conversion between deceleration and motor drive torque is the conventional technical means of those skilled in the art, and this application will not go into details here. It is worth mentioning that due to the different parameters of different vehicles, the relationship between the pedal stroke and the motor drive torque of different vehicles will also change.

[0050] In step S4 of this embodiment, the method further includes storing the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition in the cloud server for data migration when the vehicle is replaced. When performing data migration, the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition is stored in the cloud server, so the motor driving torque is first converted into the expected deceleration according to the vehicle parameters of the original vehicle, and the relationship curve between the pedal stroke and the expected deceleration under different driving conditions is obtained, and then the relationship curve between the pedal stroke and the motor driving torque is obtained by reverse deduction according to the vehicle parameters of the new vehicle.

[0051] In order to make the actual deceleration output gradually approach the driver's expected deceleration, before step S5, the method of this embodiment also includes repeatedly executing steps S2 to S4, and continuously iteratively updating the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition.

[0052] Step S5: When the driver implements the pedal stroke under the corresponding working condition, according to the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition, the vehicle braking system outputs the corresponding motor driving torque to control the output of the actual deceleration.

[0053] In summary, this embodiment can adaptively adjust the braking deceleration according to the driver's driving habits to meet the comfortable braking needs of different drivers; at the same time, the user's commonly used braking driving data information can be transferred to the new car, shortening the user's adaptation time to the vehicle.

[0054] At the same time, this embodiment also proposes an adaptive braking system with adjustable deceleration, which is configured according to the above-mentioned adaptive braking method with adjustable deceleration, and includes a sensor unit, a controller, and a braking unit, wherein the controller is connected to the sensor unit and the braking unit, respectively; the sensor unit is used to collect vehicle status data and send it to the controller; the controller is used to process the vehicle status data according to the above-mentioned adaptive braking method with adjustable deceleration so as to adjust the motor driving torque output by the braking unit to control the output of the actual deceleration.

[0055] Preferably, the brake unit includes a decoupled hydraulic brake unit or a wire-controlled brake unit, etc., which can be flexibly selected according to actual conditions.

[0056] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. An adaptive braking method with adjustable deceleration, characterized in that: The method comprises the following steps: Step S1, establishing multiple driving conditions according to the driver's driving habits; Step S2: for each driving condition, determining whether the driver intends to adjust the braking deceleration under the corresponding condition; Step S3: when the driver intends to adjust the braking deceleration, the actual deceleration of different pedal strokes under the corresponding working conditions is obtained, and the expected deceleration of the corresponding pedal stroke is calculated; Step S4, according to the expected deceleration, in combination with the vehicle parameters, the motor driving torque corresponding to the expected deceleration is inferred, and finally a relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition is fitted; Step S5: When the driver implements the pedal stroke under the corresponding working condition, according to the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition, the vehicle braking system outputs the corresponding motor driving torque to control the output of the actual deceleration.

2. The adaptive braking method with adjustable deceleration according to claim 1, characterized in that: The step S1 comprises: Step S11, when it is detected that the driver has applied braking, corresponding vehicle status data is recorded, including the vehicle speed at the start of braking, the distance to other vehicles following the vehicle or obstacles, the steering wheel angle, and the gradient of the change in the brake pedal travel; multiple vehicle status data constitute a vehicle status data set; Step S12: Divide the vehicle state data set according to a preset range to obtain segmented vehicle state data sets in different data ranges, each segmented vehicle state data set corresponding to a driving condition label.

3. The adaptive braking method with adjustable deceleration according to claim 1 or 2, characterized in that: Before step S2, the method also includes: when it is detected that the driver brakes, determining whether the current driving condition exists; when the current driving condition exists, continuing to execute step S2; when the current driving condition does not exist, establishing a driving condition label separately for the vehicle status data under the current driving condition, and continuing to execute step S2.

4. The adaptive braking method with adjustable deceleration according to claim 1, characterized in that: In step S2, the pedal stroke change amount and the pedal stroke change gradient between the current sampling point and the previous sampling point are used to determine whether the driver intends to adjust the braking deceleration. The determination conditions for whether the driver intends to adjust the braking deceleration are as follows: (1) The pedal stroke change is greater than a set first change threshold and the pedal stroke change is less than a set second change threshold, wherein the first change threshold is less than the second change threshold; (2) the pedal stroke change gradient is greater than a set first change gradient threshold and the pedal stroke change gradient is less than a set second change gradient threshold, wherein the first change gradient threshold is less than the second change gradient threshold; When (1) and (2) are satisfied at the same time, it means that the driver intends to adjust the braking deceleration; otherwise, it means that the driver has no intention to adjust the braking deceleration or has an intention to perform emergency braking; when the pedal stroke becomes smaller and the pedal stroke change gradient is negative, the driver expects to reduce the braking deceleration; when the pedal stroke becomes larger and the pedal stroke change gradient is positive, the driver expects to increase the braking deceleration.

5. The adaptive braking method with adjustable deceleration according to claim 4, characterized in that: In step 2, the driving conditions of emergency braking and auxiliary braking are also filtered, that is, when any of the following conditions occurs in the driving condition, the corresponding driving condition is excluded: the pedal stroke is greater than the set stroke threshold; The pedal travel change gradient is greater than the set second change gradient threshold; the vehicle deceleration is greater than the set deceleration threshold; the anti-lock braking system is activated; the brake assist system is activated.

6. The adaptive braking method with adjustable deceleration according to claim 1, characterized in that: In step S3, when the driver intends to adjust the braking deceleration, Get the deceleration and pedal travel at the current time t and the previous time t-1, a t and a t-1 They correspond to the deceleration at the current time t and the previous time t-1 respectively; s t and t-1 They correspond to the pedal travel at the current time t and the previous time t-1 respectively; where a t-1 That is, the pedal travel s under the current driving condition t-1 The actual deceleration; then the pedal travel s under the current driving condition t-1 The expected deceleration is Min(a t-1 ±0.1m / s 2 , (a t +a t-1 ) / 2), where Min(a t-1 -0.1m / s 2 , (a t +a t-1 ) / 2) indicates that the driver expects to reduce deceleration, Min(a t-1 +0.1m / s 2 , (a t +a t-1 ) / 2) indicates that the driver expects to increase the deceleration.

7. The adaptive braking method with adjustable deceleration according to claim 1, characterized in that: Before step S5, the method further includes repeatedly executing steps S2 to S4, and continuously iteratively updating the relationship curve between the pedal stroke and the motor driving torque under the corresponding working condition.

8. The adaptive braking method with adjustable deceleration according to claim 1, characterized in that: In step S4, the method further includes storing a relationship curve between the pedal stroke and the motor driving torque under corresponding working conditions in a cloud server for data migration when the vehicle is replaced.

9. The adaptive braking method with adjustable deceleration according to claim 8, characterized in that: During data migration, the cloud server stores the relationship curve between the pedal stroke and the motor driving torque under the corresponding working conditions. Therefore, the motor driving torque is first converted into the expected deceleration based on the vehicle parameters of the original vehicle, and the relationship curve between the pedal stroke and the expected deceleration under different driving conditions is obtained. Then, the relationship curve between the pedal stroke and the motor driving torque of the new vehicle is obtained by reverse deduction based on the vehicle parameters of the new vehicle.

10. An adaptive braking system with adjustable deceleration, characterized in that: The system is configured according to the adaptive braking method with adjustable deceleration according to any one of claims 1 to 9, and includes a sensor unit, a controller, and a braking unit, wherein the controller is connected to the sensor unit and the braking unit, respectively; the sensor unit is used to collect vehicle status data and send it to the controller; the controller is used to process the vehicle status data according to the adaptive braking method with adjustable deceleration according to any one of claims 1 to 8, so as to adjust the motor driving torque output by the braking unit to control the output of the actual deceleration.

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