Control method and device for brake protection of automobile tail door

Abstract

The invention discloses a control method and device for brake protection of an automobile tail door, and relates to the field of automobile safety control. When the current falling speed exceeds a first speed threshold value, a motor of the automobile tail door is controlled to be braked; if the current falling speed after braking is smaller than the second speed threshold and larger than a third speed threshold, the motor is controlled to increase the braking degree and then quit braking, and if the current falling speed is not larger than the third speed threshold, the motor is controlled to quit braking. And when the falling speed is high, the motor is controlled to brake, so that the falling speed of the automobile tail door is controlled. The falling speed is continuously reduced, when the falling speed is smaller than the second speed threshold value, it can be affirmed that the tail door does not need to be controlled, the motor is controlled to quit the brake, judgment of the third speed threshold value is added in the quit process, and shaking of the vehicle door is avoided. The falling speed is controlled in the falling process of the automobile tail door so as to prevent a user from being clamped, brake control is quitted after the falling speed is properly controlled, and energy loss is reduced.

Description

Technical Field

[0001] The invention relates to the field of automobile safety control, and in particular to a control method and device for automobile tailgate brake protection. Background Art

[0002] The rear tailgate systems of vehicles currently on the market generally include double-strut electric systems, single-strut electric systems, and double mechanical strut systems. In order to control costs, the life and quality of some strut systems may not be that good. If the tailgate is not able to support the vehicle due to mechanical failure, it will cause the tailgate to fall freely after opening, which may cause damage to the user. In related technologies, the tailgate brakes will be controlled, but the brakes will cause the tailgate to shake, which can also easily cause damage to the user. Summary of the invention

[0003] The purpose of the present invention is to provide a control method and device for automobile tailgate brake protection, which not only controls the falling speed of the automobile tailgate during its falling process to prevent the user from being pinched, but also exits the brake control after the falling speed is properly controlled to reduce energy loss. At the same time, the shaking of the door is avoided by judging the third speed threshold.

[0004] In order to solve the above technical problems, the present invention provides a control method for automobile tailgate brake protection, comprising:

[0005] Determining the current falling speed of the tailgate of the vehicle;

[0006] When the current falling speed exceeds a first speed threshold, controlling the motor brake of the automobile tailgate;

[0007] When the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, controlling the motor to increase the braking degree and then exit the braking, the second speed threshold is less than the first speed threshold, and the third speed threshold is less than the second speed threshold;

[0008] When the current falling speed after braking is not greater than the third speed threshold, the motor is controlled to exit braking.

[0009] On the other hand, determining the current falling speed of the tailgate of the vehicle includes:

[0010] Determine the extension and retraction degree of the support rod according to the Hall count collected by the Hall sensor integrated in the support rod, the Hall count increases when the tailgate of the automobile is opened, and decreases when the tailgate is closed;

[0011] Determine a change value of the Hall counter within a preset time, wherein the change value is positively correlated with a change speed of the tailgate of the vehicle;

[0012] When it is determined that the tailgate of the vehicle corresponding to the extension and retraction degree of the support rod is closed, the change value of the Hall counter within the preset time is characterized as the current falling speed of the tailgate of the vehicle.

[0013] On the other hand, when the current falling speed exceeds a first speed threshold, controlling the motor brake of the automobile tailgate includes:

[0014] Presetting a first brake duty ratio of a motor for a tailgate of a vehicle;

[0015] When the current falling speed exceeds a first speed threshold, the motor of the automobile tailgate is controlled to rotate in the reverse direction at the first brake duty cycle to generate a braking torque opposite to the original rotation direction.

[0016] On the other hand, when the current falling speed exceeds the first speed threshold, after controlling the motor brake of the automobile tailgate, the method further includes:

[0017] The buzzer in the car is controlled to work to prompt the door to fall.

[0018] On the other hand, after determining the current falling speed of the tailgate according to the extension and retraction degree of the support rod of the tailgate, the method further includes:

[0019] When the current falling speed does not exceed the first speed threshold, the action of the automobile tailgate is not controlled.

[0020] On the other hand, when the current falling speed exceeds the first speed threshold, after the motor brake of the tailgate of the vehicle is controlled, the method includes:

[0021] If the current falling speed is greater than the second speed threshold, the process returns to the step of controlling the motor brake of the tailgate of the automobile.

[0022] On the other hand, when the current falling speed exceeds the first speed threshold, after controlling the motor brake of the automobile tailgate, the method further includes:

[0023] Determining whether the tailgate of the vehicle is lowered into place and locked;

[0024] If the tailgate of the automobile is lowered into place and locked, the step of controlling the motor to exit the brake is entered.

[0025] On the other hand, when the current falling speed after braking is not greater than the third speed threshold, controlling the motor to exit braking includes:

[0026] Determine whether the current falling speed after braking is greater than a third speed threshold, and the third speed threshold is less than the second speed threshold;

[0027] If the current falling speed after braking is not greater than the third speed threshold, the control duty cycle of the motor is controlled to decrease from the first braking duty cycle to 0 according to a preset decreasing algorithm.

[0028] On the other hand, when the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, controlling the motor to increase the braking degree and then exit the braking comprises:

[0029] If the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, the control duty cycle of the motor is increased from the first braking duty cycle to the second braking duty cycle, and the process returns to the step of determining whether the current falling speed after braking is greater than the third speed threshold, and the second braking duty cycle is greater than the first braking duty cycle.

[0030] In order to solve the above technical problems, the present invention also provides a control device for automobile tailgate brake protection, comprising:

[0031] Memory for storing computer programs;

[0032] The processor is used to implement the steps of the above-mentioned control method for automobile tailgate brake protection when executing the computer program.

[0033] The present application provides a control method and device for automobile tailgate brake protection, which relates to the field of automobile safety control, including determining the current falling speed of the automobile tailgate; when the current falling speed exceeds the first speed threshold, controlling the motor brake of the automobile tailgate; when the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, controlling the motor to increase the braking degree and then exit the brake, and when it is not greater than the third speed threshold, controlling the motor to exit the brake. When the falling speed is fast, the motor brake is controlled to achieve the control of the falling speed of the automobile tailgate. The falling speed is continuously reduced, and when it is less than the second speed threshold, it can be determined that there is no need to control the tailgate anymore, and the motor can be controlled to exit the brake. In the process of exiting, the judgment of the third speed threshold is added to avoid the shaking of the car door. Not only the falling speed is controlled during the falling process of the automobile tailgate to prevent the user from being pinched, but also the brake control is exited after the falling speed is properly controlled to reduce energy loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A flow chart of a control method for automobile tailgate brake protection provided by the present invention;

[0036] Figure 2 A schematic structural diagram of a control device for automobile tailgate brake protection provided by the present invention. DETAILED DESCRIPTION

[0037] The core of the present invention is to provide a control method and device for automobile tailgate brake protection, which not only controls the falling speed of the automobile tailgate during its falling process to prevent the user from being pinched, but also exits the brake control after the falling speed is properly controlled to reduce energy loss. At the same time, the shaking of the door is avoided by judging the third speed threshold.

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Figure 1 The present invention provides a flow chart of a control method for a car tailgate brake protection, the control method for a car tailgate brake protection comprising:

[0040] S11: determining the current falling speed of the tailgate of the vehicle;

[0041] S12: When the current falling speed exceeds the first speed threshold, controlling the motor brake of the tailgate of the vehicle;

[0042] S13: When the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, the motor is controlled to increase the braking degree and then exit the braking, the second speed threshold is less than the first speed threshold, and the third speed threshold is less than the second speed threshold;

[0043] S14: When the current falling speed after braking is not greater than the third speed threshold, the motor is controlled to exit braking.

[0044] The rear tailgate systems of vehicles currently on the market generally include double-strut electric systems, single-strut electric systems, and double mechanical strut systems. In order to control costs, the life and quality of some strut systems may not be that good. If the tailgate support force is insufficient due to mechanical failure, it will cause the tailgate to fall freely after opening, which may cause injuries to the user.

[0045] Therefore, the state of the tailgate is determined first. If the speed of the tailgate is low during its descent, it can be considered as a state that will not affect the safety of the user. Before controlling the brake of the tailgate, it is only necessary to consider whether the descent speed of the tailgate is too fast, which may cause damage to the user. Therefore, the current descent speed of the tailgate is obtained first, and the first speed threshold is pre-set. When the current descent speed exceeds the first speed threshold, it is determined that the tailgate is likely to cause damage to the user. At this time, the motor brake of the tailgate is controlled, that is, the speed of the tailgate is controlled to decrease.

[0046] In the process of controlling the brake of the car tailgate, the current falling speed of the car tailgate will continue to decrease. When the speed drops to the second speed threshold, it is determined that the current speed of the car tailgate will not cause damage to the user, so the motor can be controlled to exit the brake at this time to reduce the resource waste caused by the brake and let the car tailgate fall naturally. That is, it not only realizes the anti-pinch of the car tailgate, but also avoids energy waste.

[0047] In actual use, the first falling speed can be set to 30 mm / s, and the second falling speed can be set to 10 mm / s.

[0048] Furthermore, if the tailgate is braked during its descent, it will cause the tailgate to shake. Therefore, the shaking of the tailgate needs to be judged by the third speed threshold. If the third speed threshold is exceeded, it is determined that there is shaking, and the shaking needs to be avoided before the brake is released. If the third speed threshold is not exceeded, it is determined that there is no shaking, and the brake can be directly released.

[0049] The present application provides a control method for the brake protection of a car tailgate, which relates to the field of automobile safety control, including determining the current falling speed of the car tailgate; when the current falling speed exceeds the first speed threshold, controlling the motor brake of the car tailgate; when the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, controlling the motor to increase the braking degree and then exit the brake, and when it is not greater than the third speed threshold, controlling the motor to exit the brake. When the falling speed is fast, the motor brake is controlled to achieve the control of the falling speed of the car tailgate. The falling speed is continuously reduced, and when it is less than the second speed threshold, it can be determined that there is no need to control the tailgate anymore, and the motor can be controlled to exit the brake. In the process of exiting, the judgment of the third speed threshold is added to avoid the shaking of the car door. Not only the falling speed is controlled during the falling process of the car tailgate to prevent the user from being pinched, but also the brake control is exited after the falling speed is properly controlled to reduce energy loss.

[0050] Based on the above embodiments:

[0051] In some embodiments, determining the current falling speed of the tailgate of the vehicle includes:

[0052] The extension and retraction degree of the strut is determined based on the Hall count collected by the Hall sensor integrated in the strut. The Hall count increases when the tailgate of the car is opened and decreases when the tailgate is closed.

[0053] Determine the change value of the Hall count within a preset time, and the change value is positively correlated with the change speed of the car tailgate;

[0054] When it is determined that the tailgate of the vehicle is closed according to the extension and retraction degree of the support rod, the change value of the Hall counter within the preset time is represented as the current falling speed of the tailgate of the vehicle.

[0055] The electric strut is integrated with a Hall sensor, which can accurately detect the position of the piston or slider inside the electric strut. When a magnetic component passes through the sensor, the sensor will generate a corresponding electrical signal change, thereby informing the control system of the extension and retraction degree of the strut. The electrical signal change is reflected in the Hall count. The Hall count gradually increases when the door is opened and gradually decreases when the door is closed. Whether it is opened electrically or manually, the Hall count will increase. Get the current movement direction of the tailgate and identify the scene after the tailgate is opened electrically or manually. By detecting the Hall count change default_Hall (calibrable) within the preset time default_time (calibrable), it is identified that the tailgate has a tendency to fall freely. For example, after the tailgate stops, the Hall count is detected to drop by 200Hall within 500ms, which means that there is a risk of falling.

[0056] In some embodiments, when the current falling speed exceeds a first speed threshold, controlling the motor brake of the tailgate of the vehicle includes:

[0057] Presetting a first brake duty ratio of a motor for a tailgate of a vehicle;

[0058] When the current falling speed exceeds the first speed threshold, the motor of the tailgate of the automobile is controlled to be reversed at a first braking duty cycle to generate a braking torque opposite to the original rotation direction.

[0059] When the tailgate falling speed is greater than a certain threshold, the brake protection logic is activated to provide the first brake duty ratio for the prop motor to brake quickly. Specifically, the forward and reverse rotation of the motor can be controlled by a number of transistors. When the brake protection logic is detected, the power polarity of the motor is instantly reversed, so that the motor generates a braking torque opposite to the original rotation direction. The braking force is adjusted by PWM.

[0060] Generally speaking, the first brake duty cycle can be 90%.

[0061] In some embodiments, when the current falling speed exceeds the first speed threshold, after controlling the motor brake of the tailgate of the vehicle, the method further includes:

[0062] Control the buzzer in the car to prompt the door to fall.

[0063] In order to enhance the warning effect, after controlling the motor brake, a buzzer can be used to output a prompt sound to remind the user to pay attention to safety. The buzzer prompt method can be to pre-set the alarm time, and directly trigger the buzzer to output a prompt sound within the alarm time during the control work. The specific alarm method is not limited in this application.

[0064] In some embodiments, after determining the current falling speed of the tailgate according to the extension and retraction degree of the support rod of the tailgate, the method further includes:

[0065] When the current falling speed does not exceed the first speed threshold, the action of the tailgate of the vehicle is not controlled.

[0066] When the current falling speed of the tailgate does not exceed the first speed threshold, it is determined that the falling speed of the tailgate is low, and there is no need to brake to control the current tailgate speed to further decrease, which causes energy waste. The tailgate can fall naturally.

[0067] In some embodiments, when the current falling speed exceeds the first speed threshold, after controlling the motor brake of the tailgate of the vehicle, the following steps are performed:

[0068] If the current falling speed is greater than the second speed threshold, the process returns to the step of controlling the motor brake of the tailgate of the automobile.

[0069] After controlling the motor brake of the car tailgate, it is necessary to continuously obtain the current falling speed of the car tailgate. In the process of dropping from the first speed threshold to the second speed threshold, the motor needs to continue braking until the speed of the car tailgate drops to the second speed threshold, and then the braking control can be exited.

[0070] In some embodiments, when the current falling speed exceeds the first speed threshold, after controlling the motor brake of the tailgate of the vehicle, the method further includes:

[0071] Determine whether the tailgate of the car is lowered into place and locked;

[0072] If the tailgate of the vehicle is lowered into place and locked, the step of controlling the motor to exit the brake is entered.

[0073] If the tailgate is closed and locked directly during the falling process, it means that the speed of the tailgate has dropped to zero, and there is no need to brake anymore. The motor can be directly controlled to exit the brake. The above detection strategy is repeated the next time the electric tailgate opening command is triggered or it is opened manually again.

[0074] In some embodiments, when the current falling speed after braking is not greater than the third speed threshold, controlling the motor to exit braking includes:

[0075] Determine whether the current falling speed after braking is greater than a third speed threshold, and the third speed threshold is less than the second speed threshold;

[0076] If the current falling speed after braking is not greater than the third speed threshold, the control duty cycle of the motor is controlled to decrease from the first braking duty cycle to 0 according to a preset decreasing algorithm.

[0077] The third speed threshold is used as the speed threshold for determining vibration. If the speed is less than the third speed threshold, it can be determined that the current vehicle tailgate vibration is small. When the brake takes effect, the tailgate can be effectively suppressed from falling. When the tailgate is about to stop, that is, when the tailgate falls at a relatively low speed, the brake protection is exited, and the braking force of 90% PWM during the previous braking is gradually restored, and 90% gradually changes to 0%. When the braking force PWM=0, there is no braking force, which also means that the abnormal falling of the tailgate has been successfully prevented.

[0078] In some embodiments, when the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, controlling the motor to increase the braking degree and then exit the braking includes:

[0079] If the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, the control duty cycle of the control motor is increased from the first braking duty cycle to the second braking duty cycle, and returns to the step of determining whether the current falling speed after braking is greater than the third speed threshold, and the second braking duty cycle is greater than the first braking duty cycle.

[0080] If the speed of the tailgate is greater than the third speed threshold, it means that the current speed of the tailgate is still relatively high and there may be shaking, so directly increasing the brake duty cycle will stop the tailgate more quickly, thus preventing the tailgate from shaking further. After preventing the tailgate from shaking, the current falling speed is not greater than the third speed threshold, and then the step of controlling the motor's control duty cycle from the first brake duty cycle to 0 will be entered according to the preset decreasing algorithm.

[0081] In summary, the solution of the present application first determines whether it is necessary to start the motor brake through the first speed threshold, and then determines whether it is necessary to exit the motor brake through the second speed threshold. In the process of exiting the motor brake, a third speed threshold is provided to determine whether to gradually reduce the brake duty cycle to 0 or to first increase the brake duty cycle to achieve anti-shake and then gradually reduce the brake duty cycle to 0.

[0082] Figure 2 The present invention provides a structural schematic diagram of a control device for automobile tailgate brake protection, wherein the control device for automobile tailgate brake protection comprises:

[0083] A memory 21, used for storing computer programs;

[0084] The processor 22 is used to implement the steps of the above-mentioned control method for automobile tailgate brake protection when executing the computer program.

[0085] For an introduction to the control device for automobile tailgate brake protection provided in the present application, please refer to the above-mentioned embodiments, which will not be described in detail here.

[0086] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0087] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0088] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for automobile tailgate brake protection, characterized in that: include: Determining the current falling speed of the tailgate of the vehicle; When the current falling speed exceeds a first speed threshold, controlling the motor brake of the automobile tailgate; When the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, controlling the motor to increase the braking degree and then exit the braking, the second speed threshold is less than the first speed threshold, and the third speed threshold is less than the second speed threshold; When the current falling speed after braking is not greater than the third speed threshold, the motor is controlled to exit braking.

2. The control method for automobile tailgate brake protection as claimed in claim 1, characterized in that: Determining the current falling speed of the tailgate of the vehicle includes: Determine the extension and retraction degree of the support rod according to the Hall count collected by the Hall sensor integrated in the support rod, the Hall count increases when the tailgate of the automobile is opened, and decreases when the tailgate is closed; Determine a change value of the Hall counter within a preset time, wherein the change value is positively correlated with a change speed of the tailgate of the vehicle; When it is determined that the tailgate of the vehicle corresponding to the extension and retraction degree of the support rod is closed, the change value of the Hall counter within the preset time is characterized as the current falling speed of the tailgate of the vehicle.

3. The control method for automobile tailgate brake protection as claimed in claim 1, characterized in that: When the current falling speed exceeds a first speed threshold, controlling the motor brake of the tailgate of the vehicle includes: Presetting a first brake duty ratio of a motor for a tailgate of a vehicle; When the current falling speed exceeds a first speed threshold, the motor of the automobile tailgate is controlled to rotate in the reverse direction at the first brake duty cycle to generate a braking torque opposite to the original rotation direction.

4. The control method for automobile tailgate brake protection as claimed in claim 1, characterized in that: When the current falling speed exceeds the first speed threshold, after controlling the motor brake of the tailgate of the automobile, the method further includes: The buzzer in the car is controlled to work to prompt the door to fall.

5. The control method for automobile tailgate brake protection as claimed in claim 1, characterized in that: After determining the current falling speed of the tailgate according to the extension and retraction degree of the support rod of the tailgate, the method further includes: When the current falling speed does not exceed the first speed threshold, the action of the automobile tailgate is not controlled.

6. The control method for automobile tailgate brake protection as claimed in claim 1, characterized in that: When the current falling speed exceeds the first speed threshold, after the motor brake of the tailgate of the vehicle is controlled, the method includes: If the current falling speed is greater than the second speed threshold, the process returns to the step of controlling the motor brake of the tailgate of the automobile.

7. The control method for automobile tailgate brake protection as claimed in claim 1, characterized in that: When the current falling speed exceeds the first speed threshold, after controlling the motor brake of the tailgate of the automobile, the method further includes: Determining whether the tailgate of the vehicle is lowered into place and locked; If the tailgate of the automobile is lowered into place and locked, the step of controlling the motor to exit the brake is entered.

8. The control method for automobile tailgate brake protection according to any one of claims 1 to 7, characterized in that: When the current falling speed after braking is not greater than the third speed threshold, controlling the motor to exit braking comprises: Determine whether the current falling speed after braking is greater than a third speed threshold, and the third speed threshold is less than the second speed threshold; If the current falling speed after braking is not greater than the third speed threshold, the control duty cycle of the motor is controlled to decrease from the first braking duty cycle to 0 according to a preset decreasing algorithm.

9. The control method for automobile tailgate brake protection as claimed in claim 8, characterized in that: When the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, controlling the motor to increase the braking degree and then exit the braking, comprises: If the current falling speed after braking is less than the second speed threshold and greater than the third speed threshold, the control duty cycle of the motor is increased from the first braking duty cycle to the second braking duty cycle, and the process returns to the step of determining whether the current falling speed after braking is greater than the third speed threshold, and the second braking duty cycle is greater than the first braking duty cycle.

10. A control device for automobile tailgate brake protection, characterized in that: include: Memory for storing computer programs; A processor is used to implement the steps of the control method for automobile tailgate brake protection as described in any one of claims 1 to 9 when executing the computer program.

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