Rack end protection method and apparatus, and electronic device

Abstract

This application provides a rack end protection method, device, and electronic device. The method includes: when the current rack end protection function of the vehicle is determined to be active, performing torque analysis processing based on the relative angle between the current angle and the steering wheel activation angle to determine a first protection torque; performing torque analysis processing based on the current rotation speed of the vehicle's steering wheel to obtain a second protection torque; and performing torque analysis processing on the first and second protection torques after determining the direction to obtain an assist torque for protecting the rack end. This application obtains the first and second protection torques based on the vehicle's current speed, steering wheel angle, and steering wheel rotation speed, thereby determining the assist torque requested from the motor, improving the flexibility and timeliness of rack end protection based on the current state of the vehicle's steering wheel, and improving the accuracy of rack end protection control.

Description

Technical Field

[0001] This application belongs to the field of power steering systems for vehicles, and specifically relates to a method, device and electronic device for protecting the end of a rack. Background Technology

[0002] In a mechanical steering system, the driver applies steering torque to the steering wheel. This torque is transmitted to the intermediate shaft via the steering column. The intermediate shaft then connects to a rack and pinion steering gear, which converts the torque into linear thrust or pull, thereby driving the wheels to steer.

[0003] When the steering wheel is turned to near its limit on one side, the steering rack will also approach the end of its travel on that side. If the driver continues to turn the steering wheel to that side, the inner ball joint at the end of the lateral tie rod connected to the rack on the other side will experience mechanical wear or impact with the steering gear housing. This can easily lead to damage to mechanical parts and also cause a bad driving experience due to the noise and abrupt feel. Therefore, it is necessary to protect the end of the rack.

[0004] Currently, methods for rack end protection often involve directly reducing the target assist current. However, this approach suffers from several drawbacks, including difficulty in parameter calibration, low accuracy in controlling the rack end protection function, and poor flexibility and timeliness in protecting the rack end based on the current state of the vehicle's steering wheel. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a method, apparatus, and electronic device for protecting the end of a rack.

[0006] On one hand, this application proposes a rack end protection method, the method comprising: acquiring the current angle of the vehicle's steering wheel, the current driving speed of the vehicle, and the current rotational speed of the vehicle's steering wheel; when it is determined that the current rack end protection function of the vehicle is in an active state, performing torque analysis processing based on the relative angle between the current angle and the steering wheel activation angle of the activated rack end protection function to determine a first protection torque that varies quadratically with the relative angle; the steering wheel activation angle is obtained by performing angle analysis processing on the current driving speed; performing torque analysis processing based on the current rotational speed of the vehicle's steering wheel to obtain a second protection torque that is linearly related to the current rotational speed; performing torque analysis processing on the first and second protection torques after determining the direction to obtain a power assist torque, wherein the power assist torque is the torque requested by the motor to output to the power steering system when the end protection function is in an active state, and the power assist torque is used to protect the rack end.

[0007] In one embodiment of the present invention, before performing torque analysis processing on the relative angle between the current angle and the steering wheel activation angle activated by the rack end protection function, the method further includes: obtaining a soft stop angle, a first angle threshold, and a second angle threshold; the soft stop angle is the angle of the steering wheel corresponding to the soft stop, the soft stop is a point where there is a preset distance between the mechanical ends of the vehicle's rack, the first angle threshold is obtained by angle calibration processing based on the vehicle's structural information, and the second angle threshold is obtained by angle calibration processing based on the vehicle's historical driving speed; performing activation angle analysis processing on the first angle threshold, the second angle threshold, and the soft stop angle to determine the activation angle of the steering wheel; and performing rack end protection function status analysis based on the current angle and the activation angle to determine the current rack end protection function status.

[0008] In one embodiment of the present invention, the step of analyzing the rack end protection function status based on the current angle and the activation angle to determine the current rack end protection function status includes: comparing the size of the current angle and the activation angle to obtain an angle comparison result; if the angle comparison result indicates that the current angle is less than or equal to the activation angle, determining that the current rack end protection function status is inactive; if the angle comparison result indicates that the current angle is greater than the activation angle, determining that the current rack end protection function status is active.

[0009] In one embodiment of the present invention, before performing torque analysis processing based on the relative angle between the current angle and the steering wheel activation angle activated by the rack end protection function to determine a first protective torque that varies quadratically with the relative angle, the method further includes: obtaining a power assist torque limit value of the vehicle's motor; correspondingly, the step of performing torque analysis processing based on the relative angle between the current angle and the steering wheel activation angle activated by the rack end protection function to determine a first protective torque that varies quadratically with the relative angle includes: summing the result of the square of the relative angle with the relative angle to obtain a first value; summing the result of the square of the second angle threshold with the second angle threshold to obtain a second value; and multiplying the ratio of the first value to the second value with the power assist torque limit value to determine a first protective torque that varies quadratically with the relative angle.

[0010] In one embodiment of the present invention, before performing torque analysis based on the current rotational speed of the vehicle's steering wheel to obtain a second protective torque linearly related to the current rotational speed, the method further includes: obtaining a rotational speed limit value of the steering wheel; determining a damping coefficient corresponding to the relative angle based on the relative angle; correspondingly, performing torque analysis based on the current rotational speed of the vehicle's steering wheel to obtain a second protective torque linearly related to the current rotational speed includes: using the ratio of the current rotational speed of the vehicle's steering wheel to the rotational speed limit value as a first multiplier; multiplying the first multiplier by the damping coefficient and the assist torque limit value to obtain a second multiplier; and generating a second protective torque linearly related to the current rotational speed based on the second multiplier.

[0011] In one embodiment of the present invention, the step of performing activation angle analysis processing on the first angle threshold, the second angle threshold, and the soft stop angle to determine the activation angle of the steering wheel includes: taking the difference between the soft stop angle and the first angle threshold as a first difference; and determining the activation angle of the steering wheel based on the difference between the first difference and the second angle threshold.

[0012] In one embodiment of the present invention, before performing torque analysis processing on the first and second protective torques after determining their directions to obtain the assist torque, the method further includes: performing direction analysis processing based on the direction of the vehicle's current angle to determine the direction of the first protective torque; and performing direction analysis processing based on the direction of the vehicle's current rotational speed to determine the direction of the second protective torque.

[0013] In one embodiment of the present invention, the step of performing torque analysis processing on the first and second protective torques after determining the direction to obtain the assisting torque includes: superimposing the first and second protective torques after determining the direction to obtain the end protection torque of the rack output by the end protection function module; the rack is the output end of the end protection function module; obtaining the torque output by other function modules; the other function modules are modules other than the end protection function module; superimposing the end protection torque of the rack output by the end protection function module and the torque output by other function modules to obtain the assisting torque; wherein, the end protection torque refers to the torque reduced by the motor to protect the end of the rack.

[0014] On the other hand, this application provides a rack end protection device, the device comprising: a parameter acquisition module for acquiring the current angle of the vehicle's steering wheel, the current driving speed of the vehicle, and the current rotational speed of the vehicle's steering wheel; a first protection torque analysis module for determining a first protection torque that varies quadratically with the relative angle between the current angle and the steering wheel activation angle when the current rack end protection function is determined to be active; the steering wheel activation angle is obtained by angle analysis of the current driving speed; a second protection torque analysis module for obtaining a second protection torque that is linearly related to the current rotational speed of the vehicle's steering wheel by performing torque analysis; and a power assist torque analysis module for obtaining a power assist torque by performing torque analysis on the first and second protection torques after the direction is determined, wherein the power assist torque is the torque requested from the motor to the power steering system when the end protection function is active, and the power assist torque is used to protect the rack end.

[0015] On the other hand, the present invention proposes an electronic device comprising a processor and a memory, wherein the memory stores at least one instruction or at least one program, the at least one instruction or the at least one program being loaded by the processor and executed as described in any of the preceding methods.

[0016] The rack end protection method and device proposed in this invention, when the rack end protection function is activated, analyzes the current driving speed of the vehicle and the current rotation speed and angle of the vehicle's steering wheel to obtain a first protection torque and a second protection torque. Further analysis and processing are then performed to obtain an assist torque for protecting the rack end, thereby improving the flexibility and timeliness of protecting the rack end based on the current state of the vehicle's steering wheel and enhancing the accuracy of applying rack end protection. Attached Figure Description

[0017] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 1 .

[0019] Figure 2This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 2 .

[0020] Figure 3 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 3 .

[0021] Figure 4 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 4 .

[0022] Figure 5 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 5 .

[0023] Figure 6 This is a block diagram of a rack end protection device according to an exemplary embodiment.

[0024] Figure 7 This is a schematic diagram illustrating the principle of a rack and pinion steering system according to an exemplary embodiment.

[0025] Figure 8 This is a schematic diagram illustrating the activation position of an end protection function according to an exemplary embodiment.

[0026] Figure 9 This is a graph illustrating the relationship between a first protective torque and a relative angle, according to an exemplary embodiment.

[0027] Figure 10 This is a graph illustrating the relationship between the second protective torque and the relative angle at different steering wheel speeds, according to an exemplary embodiment.

[0028] The following is supplementary explanation of the attached figures: 1-Steering wheel, 2-Steering column, 3-Intermediate shaft, 4-Steering gear housing, 5-Pin gear, 6-Steering rack, 7-Inner ball joint, 8-Tie rod, 9-Outer ball joint, 10-Steering knuckle arm, 11-Steering wheel Detailed Implementation The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of the embodiments of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the present application described herein can be implemented in orders other than those illustrated or described herein. Thus, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments, unless otherwise stated, "a plurality of" means two or more. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or server that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices.

[0030] To make the objectives, technical solutions, and advantages disclosed in the embodiments of this application clearer, the embodiments of this application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of this application and are not intended to limit the embodiments of this application.

[0031] It should be noted that the "rack" and "steering rack" referred to in this technical solution are the same component, and "both ends of the rack," "two ends of the rack," and "two ends of the rack" all have the same meaning. Below, to facilitate understanding of the above-mentioned technical solutions and their resulting technical effects in the embodiments of this application, the relevant technical terms are first explained:

[0032] This application does not impose specific limitations on the positive or negative values ​​of the steering wheel angle or the rotation direction. For ease of understanding of the technical solution of this invention, one example is used for illustration. Those skilled in the art will understand that the steering wheel direction and rotation direction in the technical solution of this invention can be set in other ways, such as clockwise being negative and counterclockwise being positive. The following description does not constitute a limitation on the scope of the technical solution of this invention. It should be noted that the following directions are all based on the driver's position directly facing the steering wheel when seated in the driver's seat. The first and second protective torques are both positive when the rack's zero position points to the rack's last position. Regarding the steering wheel angle, with the steering wheel at zero position as a reference, turning it clockwise results in a positive sign for the steering wheel angle, while turning it counterclockwise results in a negative sign for the steering wheel angle.

[0033] Regarding the first protective torque, the sign of the first protective torque is opposite to the sign of the steering wheel angle. When the steering wheel angle sign is positive, the sign of the first protective torque is negative; when the steering wheel angle is negative, the direction of the first protective torque is positive.

[0034] Regarding the direction of steering wheel rotation speed, it is stipulated that when the steering wheel is turned clockwise, the rotation speed direction is positive, and when it is turned counterclockwise, the rotation speed direction is negative.

[0035] Regarding the second protective torque, the sign of the direction of the second protective torque is opposite to the sign of the steering wheel rotation direction. When the steering wheel rotation is clockwise, the sign of the second protective torque is negative; when the steering wheel rotation is counterclockwise, the sign of the second protective torque is positive.

[0036] Figure 7 This is a schematic diagram illustrating the principle of a rack and pinion steering system according to an exemplary embodiment, such as... Figure 7 As shown, the basic structure of a rack and pinion steering gear consists of a pair of meshing pinions 5, a steering rack 6, and an external steering housing 4. The two ends of the steering rack 6 are connected to lateral tie rods 8, which are the rack ends. Ball joints are connected to the ends of the lateral tie rods 8; the ball joint closer to the rack is the inner ball joint 7, and the ball joint further away is the outer ball joint 9. The steering wheel 1 is connected to the steering column 2, and the steering column 2 is connected to the intermediate shaft 3. The torque applied to the steering wheel is transmitted sequentially to the intermediate shaft 3 through the above structure. On the pinion 5 connected to the shaft 3, the pinion 5 meshes with the steering rack 6, driving the steering rack 6 to move linearly left or right within the steering housing 4. The steering housing 4 remains stationary. Since the steering knuckle arm 10 moves synchronously with the steering rack 6, the steering knuckle arm 10 drives the steering wheel 11 to change direction. The two ends of the two racks of the steering rack 6 are respectively provided with inner ball joints 7. The steering rack is installed within the steering housing 4. It should be noted that this application does not restrict the rotation direction of the pinion 5. Figure 7 The pinion 5 shown is a right-handed gear. Exemplarily, in other possible embodiments, the pinion 5 may also be a left-handed gear.

[0037] As mentioned earlier, taking the driver's position facing the steering wheel when seated in the driver's seat as a reference, turning the steering wheel clockwise causes the pinion 5 to rotate clockwise, thus engaging with the steering rack 6. The steering rack 6 moves in a straight line to the right. When the steering wheel rotates to near its end position, one end of the steering rack 6 also approaches its end position, and the inner ball joint 7 at the end of the steering rack 6 approaches the edge of the steering gear housing 4. If no rack end protection function is provided, when the steering wheel reaches its end position, the other end of the steering rack 6 will collide with the steering gear housing 4. Therefore, to prevent the steering rack 6 from moving to its end position when the steering wheel moves to its end position, a soft stop and a protective torque are set in the electric power steering system to achieve rack end protection.

[0038] Figure 1 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 1 , Figure 2 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 2 , Figure 3 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 3 , Figure 4 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 4 , Figure 5 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 5 , Figure 6 This is a block diagram of a rack end protection device according to an exemplary embodiment. Figure 7 This is a schematic diagram illustrating the principle of a rack and pinion steering system according to an exemplary embodiment. Figure 8 This is a schematic diagram illustrating the activation position of an end protection function according to an exemplary embodiment. Figure 9 This is a graph illustrating the relationship between a first protective torque and a relative angle, according to an exemplary embodiment. Figure 10 This is a graph illustrating the relationship between the second protective torque and the relative angle at different steering wheel speeds, according to an exemplary embodiment.

[0039] This specification provides the operational steps of the methods described in the embodiments or flowcharts, but based on conventional or non-inventive labor, more or fewer operational steps may be included. The order of steps listed in the embodiments is merely one possible execution order among many and does not represent the only execution order. In actual system or server products, the methods shown in the embodiments or drawings can be executed sequentially or in parallel (e.g., in a parallel processor or multi-threaded processing environment). Specifically, as shown in the embodiments or drawings... Figure 1 As shown, the method may include: S102: Obtain the current steering wheel angle, the current vehicle speed, and the current steering wheel rotation speed; S104: When it is determined that the current rack end protection function of the vehicle is activated, torque analysis is performed based on the relative angle between the current angle and the steering wheel activation angle of the rack end protection function to determine a first protection torque that varies with the relative angle in a quadratic curve; the steering wheel activation angle is obtained by angle analysis of the current driving speed. S106: Perform torque analysis based on the current rotation speed of the vehicle's steering wheel to obtain a second protective torque that is linearly related to the current rotation speed; Torque analysis processing of the current speed of the steering wheel refers to analyzing and processing the obtained current speed through methods such as linear fitting to obtain a second protective torque that is linearly related to the current speed.

[0040] S108: Perform torque analysis on the first and second protection torques after determining the direction to obtain the assist torque. The assist torque is the torque requested by the motor to output to the power steering system when the end protection function is activated. The assist torque is used to protect the end of the rack.

[0041] like Figure 7 As shown, for a rack and pinion steering gear, since the rotation of the steering wheel and the linear motion of the rack are synchronous, the steering wheel angle and the rack position correspond one-to-one. The two can be converted according to the transmission ratio. For ease of calculation and testing, the steering wheel angle is used to represent the rack position. Therefore, the current angle of the steering wheel can represent the current rack position.

[0042] The current angle of the vehicle's steering wheel represents the angle of the steering wheel relative to the zero position, which can indirectly indicate the position of the rack. The current angle is used to determine whether the rack end protection function of the vehicle's steering wheel is activated. The relative angle is the difference between the current angle and the activated angle, representing the angle of the steering wheel relative to the activated angle. The vehicle's current speed can be used to determine the activated angle and the first protection torque. The current rotational speed of the vehicle's steering wheel is related to the determination of the second protection torque. Therefore, it is necessary to obtain and analyze the above parameters.

[0043] When the rack end protection function is confirmed to be active, the rack end protection function enters the running state. By analyzing the parameters such as the current driving speed, current rotation speed, relative angle, and current angle obtained above, the first protection torque and the second protection torque can be determined, thereby determining the motor's assist torque. The direction of the first protection torque is from the rack end position to the rack zero position.

[0044] Furthermore, within the steering wheel angle range where the rack end protection function is activated, the first protective torque is effective regardless of whether the driver turns towards the rack end position or towards the rack zero position. If the driver turns towards the rack end position, such as... Figure 9 As shown, the first protective torque changes with the relative angle in a quadratic curve, effectively reducing the motor assist and preventing mechanical impact at the end. If the driver switches from the rack end position to the rack zero position, since the rack end position is in the rack end protection function activation zone, the basic motor assist has been reduced to a low level, and the driver needs to exert more force to achieve steering. At this time, the first protective torque from the rack end position to the rack zero position can provide assistance, making it easier for the driver to turn from the rack end position to the rack zero position.

[0045] Furthermore, regarding the second protective torque, such as Figure 10 As shown, when the rotational speed is constant, the second protective torque increases linearly with the relative angle. When the relative angle is constant, the second protective torque increases with the increase of rotational speed.

[0046] Furthermore, based on the signs of the current steering wheel angle and steering wheel speed, it can be determined whether the current position is the last position or the zero position of the steering rack, as follows: if the signs of the current steering wheel angle and steering wheel speed are the same, then the steering wheel is turning from the zero position to the last position of the rack; conversely, if the signs of the current steering wheel angle and steering wheel speed are different, then the steering wheel is turning from the last position to the zero position of the rack.

[0047] For example, when the steering wheel angle is positive, rotating the steering wheel clockwise will result in a positive steering wheel speed sign, consistent with the steering wheel angle direction, indicating that the steering wheel is currently turning from the zero position of the rack to the last position. When the steering wheel angle is positive, rotating the steering wheel counterclockwise will result in a negative steering wheel speed sign, opposite to the steering wheel angle direction, indicating that the steering wheel is currently turning from the last position of the rack to the zero position. When the steering wheel angle is negative, based on a similar principle, it is possible to determine whether the steering wheel is turning to the last position or the zero position of the rack, which will not be elaborated here.

[0048] The rack end protection method and device proposed in this invention, when the rack end protection function is activated, analyzes the current driving speed of the vehicle and the current rotation speed and angle of the vehicle's steering wheel to obtain a first protection torque and a second protection torque. Further analysis and processing are then performed to obtain an assist torque for protecting the rack end, thereby improving the flexibility and timeliness of protecting the rack end based on the current state of the vehicle's steering wheel and enhancing the accuracy of applying rack end protection.

[0049] Figure 2 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 2 ,like Figure 2 As shown, in one embodiment of the present invention, before performing torque analysis processing based on the relative angle between the current angle and the steering wheel activation angle activated by the rack end protection function, the method further includes: S002: Obtain the soft stop angle, the first angle threshold, and the second angle threshold; The soft stop angle is the steering wheel angle corresponding to the soft stop, and the soft stop is a point where there is a preset distance between the mechanical ends of the vehicle's rack.

[0050] The first angle threshold and the second angle threshold are both obtained by calibration during the vehicle testing phase. The vehicle's structural information refers to different models and different steering assemblies. The first angle threshold is an angle calibrated taking into account factors such as the vehicle structure, which can make the mechanical impact at the end of the rack gentler. Optionally, the range of the first angle threshold can be 0~15°. Different vehicles may have different first angle thresholds, but for the same vehicle, after calibration, the first angle threshold and the second angle threshold are both fixed values.

[0051] Furthermore, the second angle threshold is calibrated based on historical vehicle speeds. The second angle threshold decreases as the vehicle speed increases, indicating that the faster the vehicle speed, the later the rack end protection function is activated. Optionally, the range of the second angle threshold can be 0~50°. For example, at two vehicle speeds A and B (A<B), the second angle threshold is different, the activation angle is different, and the time to enter the rack end protection function activation state is different. When the vehicle speed is A, the calibrated second angle threshold is 30°, and when the vehicle speed is B, the calibrated second angle threshold is 20°. Since the activation angle is obtained by subtracting the second angle threshold and the first angle threshold from the soft stop angle, the smaller the second angle threshold, the larger the activation angle, and the later the rack end protection function is activated.

[0052] S004: Perform activation angle analysis processing on the first angle threshold, the second angle threshold, and the soft stop angle to determine the activation angle of the steering wheel; Further, the activation angle is determined based on the first angle threshold, the second angle threshold, and the soft stop angle. The activation angle analysis process refers to the analysis process of calculating the difference between the first angle threshold, the second angle threshold, and the soft stop angle. For example, ; This indicates the soft stop angle for rack end protection. Optionally, the soft stop angle is obtained through calibration or rack end position self-learning. Indicates the first angle threshold. Represents the second angle threshold, where The activation angle indicates the angle of the steering wheel relative to the zero position when the rack end protection function is activated. This is to ensure that the feel changes on both sides of the rack zero position are consistent. All values ​​are positive. Using the activation angle as a reference, the current angle is judged to determine whether the current steering wheel angle activates the rack end protection function.

[0053] S006: Analyze the rack end protection function status based on the current angle and the activation angle to determine the current rack end protection function status.

[0054] The rack end protection method proposed in this invention introduces a first angle threshold and a second angle threshold, which increases the consideration of the influence of vehicle structure factors and current vehicle speed on the rack end protection function. The activation angle is obtained by analyzing the soft stop angle of the vehicle's steering wheel and the first and second angle thresholds. Using the activation angle as a reference, the current angle of the vehicle's steering wheel is analyzed to determine whether the current steering wheel is in an activated state for the rack end protection function. This changes the angle at which the rack end protection function is activated from the soft stop angle to a smaller activation angle, thereby increasing the activation range of the end protection function, enhancing the protection strength of the rack end protection function, further reducing the possibility of collision between the rack end and the steering gear housing, improving the driver's steering feel, and improving the accuracy and timeliness of determining the activation state of the rack end protection function.

[0055] In one embodiment of the present invention, step S008, analyzing the rack end protection function status based on the current angle and the activation angle to determine the current rack end protection function status, includes: The current angle and the activated angle are compared to obtain an angle comparison result; if the angle comparison result indicates that the current angle is less than or equal to the activated angle, the current rack end protection function is determined to be inactive; if the angle comparison result indicates that the current angle is greater than the activated angle, the current rack end protection function is determined to be active.

[0056] like Figure 8 As shown, with the activation angle Using this as a dividing point, the angle range is divided into the active and inactive ranges for rack end protection. This is achieved by comparing the current angle... and activation angle The magnitude of the value determines the range of the current angle. At the current angle... Less than or equal to the activation angle At present, angle It is not within the activation range, therefore it can be determined that the current rack end protection function is inactive at the current angle. Greater than the activation angle When the rack enters the activation range, the rack end protection function is currently in the activated state.

[0057] The rack end protection method proposed in this invention compares the current angle and the activation angle, and determines whether the current position of the rack is in a position that activates the rack end protection function based on the angle relationship of the steering wheel. This improves the simplicity and efficiency of the rack state judgment method, thereby enabling an immediate response when the rack position approaches the rack end, and enhancing the ability to react to potential collisions with the rack.

[0058] Figure 3 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 3 ,like Figure 3 As shown, in one embodiment of the present invention, before performing torque analysis processing based on the relative angle between the current angle and the steering wheel activation angle activated by the rack end protection function in step S104 to determine the first protection torque that varies with the relative angle in a quadratic curve, the method further includes: S1002: Obtain the limit value of the assist torque of the motor of the vehicle; Accordingly, the torque analysis process described in S104, based on the relative angle between the current angle and the steering wheel activation angle activated by the rack end protection function, to determine the first protection torque that varies with the relative angle in a quadratic curve includes: S1042: Summing the result of the square of the relative angle with the relative angle to obtain a first value, summing the result of the square of the second angle threshold with the second angle threshold to obtain a second value, multiplying the ratio of the first value to the second value with the assist torque limit value to determine a first protective torque that varies with the relative angle in a quadratic curve.

[0059] The torque analysis here involves squaring, summing, ratioing, and multiplying the relative angle, the first angle threshold, and the second angle threshold to determine the motor's assist torque limit value. It is the maximum assist torque that the motor can output, which depends on the motor's performance. in, This is a relative angle, which is the difference between the current steering wheel angle and the activated angle. The second angle threshold for rack end protection. This represents the limit value of the motor's assist torque. This indicates the first protective torque.

[0060] The rack end protection method proposed in this invention improves the controllability of rack end protection and the accuracy of determining the torque to be applied to protect the rack end by determining a first protection torque that varies quadratically with respect to the relative angle between the current angle and the activation angle of the steering wheel when the rack end protection function is activated.

[0061] Figure 4 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 4 ,like Figure 4 As shown, in one embodiment of the present invention, before S106 performs torque analysis based on the current rotational speed of the vehicle's steering wheel to obtain a second protective torque that is linearly related to the current rotational speed, the method further includes: S1004: Obtain the steering wheel speed limit value; The speed limit value refers to the maximum speed that the vehicle's steering wheel can reach. This application does not specifically limit the speed limit value. The speed limit value depends on the vehicle's structure and performance. The speed limit value is used to calculate the second protection torque.

[0062] S1006: Determine the damping coefficient corresponding to the relative angle based on the relative angle; This application does not limit the method for determining the damping coefficient. For example, the damping coefficient can be obtained by looking up a one-dimensional linear interpolation table based on the relative angle between the current absolute value of the steering wheel angle and the steering wheel angle when the rack end protection function is activated. Alternatively, the damping coefficient can be obtained by combining the steering wheel rotation speed with the current vehicle speed. Furthermore, in order to set different damping feel when turning towards the rack end and when turning towards the rack zero position, different damping coefficient interpolation tables can be used respectively. Preferably, the damping coefficient is set to 0 when turning from the rack end position to the rack zero position to reduce the damping feel when returning to the zero position.

[0063] Accordingly, the torque analysis processing described in S106, which performs torque analysis based on the current rotational speed of the vehicle's steering wheel to obtain a second protective torque that is linearly related to the current rotational speed, includes: S1062: The ratio of the current speed of the vehicle's steering wheel to the speed limit value is used as the first multiplier, and the first multiplier is multiplied by the damping coefficient and the power assist torque limit value to obtain the second multiplier; S1064: Generate a second protective torque that is linearly related to the current rotational speed according to the second multiplier.

[0064] Optionally, the second protective torque Where V represents the current speed of the steering wheel. This indicates the maximum possible steering wheel rotation speed. This represents the damping coefficient, which ranges from 0 to 1. This indicates the maximum assist torque of the motor. This indicates the second protective torque.

[0065] This application does not limit the way the second protection torque is generated based on the second multiplier. For example, in one embodiment, the second multiplier is directly used as the second protection torque. Further, in another embodiment, the current rotational speed can be weighted and analyzed to obtain a weighting factor, and the second multiplier can be multiplied by the weighting factor to obtain the second protection torque.

[0066] The rack end protection method proposed in this invention analyzes the current rotation speed of the steering wheel to determine the magnitude of the second protection torque adapted to the current steering wheel state, thereby determining the assist torque output by the motor. This improves the immediacy and flexibility of rack end protection, making the rack end protection scheme more closely related to the current steering wheel state, thus enhancing the adaptability of the rack end protection function in multiple states and optimizing the driver's feel for steering wheel operation.

[0067] In one embodiment of the present invention, step S006, which involves performing activation angle analysis on the first angle threshold, the second angle threshold, and the soft stop angle to determine the activation angle of the steering wheel, includes: The difference between the soft stop angle and the first angle threshold is taken as the first difference. Based on the difference between the first difference and the second angle threshold, the activation angle of the steering wheel is determined.

[0068] The activation angle analysis process involves calculating the difference between the first angle threshold and the soft stop angle to obtain the first difference, and then analyzing the difference between the first difference and the second angle threshold. The soft stop angle is the steering wheel angle corresponding to the soft stop. The soft stop is a point where there is a preset distance between the mechanical ends of the vehicle's rack. By setting the soft stop, the inner ball joint at the end of the rack can be prevented from colliding with the steering gear housing when the steering wheel is turned close to its end position. This is a way to protect the rack end. Considering the influence of factors such as vehicle structure and vehicle speed, the torque output of the motor is adjusted. The first and second angle thresholds are determined through simulation. As mentioned earlier, the first angle threshold is related to the vehicle model and steering assembly. For the same vehicle, the first angle threshold remains unchanged, while the second angle threshold is related to the vehicle speed and decreases as the vehicle speed increases. Introducing the first and second angle thresholds can reduce the activation angle, allowing the steering wheel angle to enter the rack end protection function activation range more quickly, thereby shortening the time to enter the rack end protection function activation state.

[0069] The rack end protection method proposed in this invention adjusts the torque output of the motor and determines a first angle threshold and a second angle threshold through simulation. This determines the activation angle representing the active state of the rack end protection function, shortens the time to enter the active state of the rack end protection function, and enhances the protection strength of the rack end protection. Furthermore, by determining different second angle thresholds based on the current vehicle speed, different activation angles can be determined, which can improve the accuracy and flexibility of rack end protection.

[0070] In one embodiment of the present invention, before performing torque analysis processing on the first and second protective torques after determining the direction in step S108 to obtain the assisting torque, the method further includes: The direction of the first protective torque is determined by performing directional analysis based on the direction of the vehicle's current angle. The direction of the second protective torque is determined by performing directional analysis based on the direction of the vehicle's current rotational speed.

[0071] Torque is a physical concept that reflects magnitude and direction. Since the activation status of the rack end protection function is determined based on the steering wheel angle, only the magnitude of the current steering wheel angle is taken and the actual angle sign is not considered, the direction of steering wheel rotation is not considered during the torque analysis stage.

[0072] For example, when the steering wheel is turned 50 degrees clockwise, it has rotated 50 degrees relative to the zero position of the steering wheel. The current angle of the steering wheel is 50 degrees. When the first protection torque and the second protection torque are finally output, the direction of the first protection torque and the second protection torque must be judged respectively, and their positive and negative signs are determined by the steering wheel angle and the direction of the steering wheel speed.

[0073] The direction analysis processing refers to the analysis and processing operation that determines the direction according to the set direction rules. This application does not limit the specific method of direction analysis processing. For example, the technical solution of this invention is described with the direction set in the beginning of the specification. Taking the zero position of the steering wheel as a reference, the sign of the current angle of the steering wheel is determined. For example, rotating the steering wheel clockwise results in a positive sign for the steering wheel angle, and rotating it counterclockwise results in a negative sign for the steering wheel angle. Regarding the direction of the current rotation speed of the steering wheel, it can be set that when the steering wheel rotates clockwise, the current rotation speed direction is positive, and when the steering wheel rotates counterclockwise, the current rotation speed direction is negative. If the current rotation speed direction is positive, the direction of the second protective torque is negative; if the current rotation speed direction is negative, the direction of the second protective torque is positive. The direction of the second protective torque is determined based on this. In other embodiments, it can also be set that when rotating counterclockwise, the sign of the steering wheel angle is positive, and when rotating clockwise, the sign of the steering wheel angle is negative. The current rotation speed direction can also be set in the opposite way, which will not be elaborated here.

[0074] Furthermore, since the current steering wheel angle is within the rack end protection activation range, that is, the steering wheel position is close to the end of the steering wheel, in order to avoid collision between the steering gear housing and the end of the rack, the steering wheel needs to be rotated from the end of the steering wheel to the zero position. At this time, the direction of the first protective torque is from the end of the rack to the zero position of the rack, and the first protective torque plays the role of increasing power assistance; conversely, when the steering wheel is rotated from the zero position to the end position, the first protective torque plays the role of reducing power assistance.

[0075] Furthermore, the second protective torque is linearly related to the current speed, so the direction of the second protective torque is related to the current speed. The function of the second protective torque is to hinder the rotation of the steering wheel, which is a damping torque and is opposite to the current speed of the steering wheel.

[0076] The rack end protection method proposed in this invention improves the consistency of the feel change pattern on both sides of the rack zero position by taking positive values ​​for the soft stop angle, the first angle threshold, and the second angle threshold during calculation, and then determining the sign after calculating the first protection torque and the second protection torque. This reduces the complexity of the calculation process, optimizes the direction judgment method, and improves the driving feel.

[0077] Figure 5 This is a flowchart illustrating a rack end protection method according to one embodiment. Figure 5 ,like Figure 5 As shown, in one embodiment of the present invention, the torque analysis processing of the first and second protective torques after determining the direction in step S108 to obtain the assisting torque includes: S1082: The first and second protective torques after the direction is determined are superimposed to obtain the end protection torque of the rack output by the end protection function module; the rack is the output end of the end protection function module; The end protection torque consists of two parts: a first protection torque and a second damping torque. Optionally, the first protection torque varies with the relative angle between the current steering wheel angle and the end protection function activation angle in a quadratic curve, which can simulate the variation law of spring torque with displacement; the second protection torque varies linearly with the steering wheel speed, which can simulate the variation law of torque with speed, thereby effectively improving the driving feel near the end position of the rack. The analysis and processing of the first protection torque and the second protection torque can specifically include the analysis and processing of summing the first protection torque and the second protection torque.

[0078] S1084: Obtain the torque output from other functional modules; The other functional modules are modules other than the end protection functional module; the other functional modules include at least the active return function, the basic assist function, and the damping function module. Correspondingly, the torque output by the other functional modules is the torque output by the active return function module, the basic assist module, the damping module, and other other functional modules.

[0079] S1086: The end protection torque of the rack output by the end protection function module is superimposed with the torque output by other function modules to obtain the assist torque; The end protection torque refers to the reduced output torque of the motor to protect the end of the rack.

[0080] When the rack position is close to the end of the rack, correspondingly, when the steering wheel angle enters the activation range of the rack end protection function, the torque to be requested from the motor is determined by superimposing the end protection torque with the torque output by other functional modules.

[0081] The rack end protection method proposed in this invention calculates the change in motor assist torque by superimposing the first and second protection torques with the torques of other functional modules. This improves the accuracy of controlling the amount of motor assist when approaching the rack end, thereby preventing mechanical wear and impact between the rack end and the steering gear housing, reducing the difficulty of controlling the output assist torque of the motor, and improving the driving feel near the rack end.

[0082] Figure 6 This is a block diagram illustrating a rack end protection device according to an exemplary embodiment. It should be noted that the device embodiments provided in this application are based on the same inventive concept as the method embodiments described above. Figure 6 As shown, the rack end protection device 600 may include at least: The parameter acquisition module 602 is used to acquire the current angle of the vehicle's steering wheel, the current driving speed of the vehicle, and the current rotation speed of the vehicle's steering wheel; The first protective torque analysis module 604 is used to determine a first protective torque that varies with a quadratic curve based on the relative angle between the current angle and the steering wheel activation angle when the current rack end protection function of the vehicle is determined to be active. The steering wheel activation angle is obtained by performing angle analysis on the current driving speed. The second protective torque analysis module 606 is used to perform torque analysis processing based on the current rotation speed of the vehicle's steering wheel to obtain a second protective torque that is linearly related to the current rotation speed. The assist torque analysis module 608 is used to perform torque analysis processing on the first protection torque and the second protection torque after the direction is determined, so as to obtain the assist torque. The assist torque is the torque requested by the motor to output to the power steering system when the end protection function is activated. The assist torque is used to protect the end of the rack.

[0083] In an optional embodiment, the device further includes an activation angle determination module, the activation angle determination module comprising: An angle acquisition module is used to acquire the soft stop angle, a first angle threshold, and a second angle threshold; the soft stop angle is the angle of the steering wheel corresponding to the soft stop, the soft stop is a point where there is a preset distance between the mechanical ends of the vehicle's rack, the first angle threshold is obtained by angle calibration processing based on the vehicle's structural information, and the second angle threshold is obtained by angle calibration processing based on the vehicle's historical driving speed. The activation angle determination module is used to perform activation angle analysis processing on the first angle threshold, the second angle threshold and the soft stop angle to determine the activation angle of the steering wheel. The rack end protection function status determination module is used to analyze the rack end protection function status based on the current angle and the activation angle, and determine the current rack end protection function status.

[0084] In one optional embodiment, the rack end protection function status determination module includes: An angle size comparison module is used to compare the current angle and the activated angle to obtain an angle comparison result; The angle comparison result analysis module is used to determine that the current rack end protection function is inactive when the angle comparison result indicates that the current angle is less than or equal to the activation angle; and to determine that the current rack end protection function is active when the angle comparison result indicates that the current angle is greater than the activation angle.

[0085] In an optional embodiment, the device further includes: A torque limit value acquisition module is used to acquire the assist torque limit value of the vehicle's motor. Accordingly, the first protective torque analysis module includes: The first protective torque determination module is used to sum the result of the square of the relative angle with the relative angle to obtain a first value, sum the result of the square of the second angle threshold with the second angle threshold to obtain a second value, and multiply the ratio of the first value to the second value with the assist torque limit value to determine the first protective torque that changes in a quadratic curve with the relative angle.

[0086] In an optional embodiment, the device further includes: The speed limit value acquisition module is used to acquire the speed limit value of the steering wheel. The damping coefficient determination module is used to determine the damping coefficient corresponding to the relative angle based on the relative angle.

[0087] Accordingly, the second protective torque analysis module includes: The multiplier determination module is used to take the ratio of the current speed of the vehicle's steering wheel to the speed limit value as the first multiplier, and multiply the first multiplier by the damping coefficient and the assist torque limit value to obtain the second multiplier; The second protective torque generation module is used to generate a second protective torque that is linearly related to the current rotational speed based on the second multiplier.

[0088] In one optional embodiment, the activation angle determination module includes: The difference determination activation angle module is used to take the difference between the soft stop angle and the first angle threshold as the first difference, and determine the activation angle of the steering wheel based on the difference between the first difference and the second angle threshold.

[0089] In an optional embodiment, the device further includes: The first protective torque direction determination module is used to determine the direction of the first protective torque based on the direction of the vehicle's current angle through direction analysis processing. The second protective torque direction determination module is used to perform directional analysis processing based on the direction of the vehicle's current rotational speed to determine the direction of the second protective torque.

[0090] In one optional embodiment, the assist torque analysis module includes: The end protection torque determination module is used to superimpose the first protection torque and the second protection torque after the direction is determined to obtain the end protection torque of the rack output by the end protection function module; The torque acquisition module for other functional modules is used to acquire the torque output by other functional modules; the other functional modules are modules other than the end protection functional module. The assist torque determination module is used to superimpose the end protection torque of the rack output by the end protection function module and the torque output by other function modules to obtain the assist torque; The end protection torque refers to the reduced output torque of the motor to protect the end of the rack.

[0091] Figure 8 This is a schematic diagram illustrating the activation position of an end protection function according to an exemplary embodiment, such as... Figure 8 As shown, between the rack zero position and the rack mechanical end, with The steering wheel angle can be divided into two regions based on the activation angle: the inactive range D of the rack end protection function and the active range R of the end protection function. At the current angle... Achieve activation angle In this case, it enters the end-function protection activation range R.

[0092] Figure 9 This is a first protective torque illustrated according to an exemplary embodiment. and relative angle Relationship curves, such as Figure 9 As shown, the steering wheel angle range activated by the rack end protection function is the activation angle. Angle to soft stop The first segment represents the second angle threshold. Segment II represents the first angle threshold. In relative angle Less than the second angle threshold Within the range, the first protective torque With relative angle The increase of follows a quadratic curve relationship, when the relative angle Reaching the second angle threshold First protective torque Reaching the motor's assist torque limit value When the relative angle is greater than the second angle threshold Within the range, the first protective torque The size no longer changes with the relative angle It increases as it grows.

[0093] Figure 10 This is an exemplary embodiment illustrating a second protective torque at different steering wheel speeds. Relative angle Relationship curves, such as Figure 10 As shown, at relative angles Under the same conditions, for different steering wheel speeds Corresponding to different second protective torques ; at a relative angle Under the same conditions, the higher the steering wheel speed, the greater the second protective torque. The larger the value, the greater the second protective torque when the steering wheel rotation speed is the same. The magnitude of the angle increases linearly with the relative angle. Equal to the second angle threshold In this case, the second protective torque The size reaches its maximum value; at a relative angle Greater than the second angle threshold Within the range, the second protective torque No longer with relative angle Increases as it increases.

[0094] This application also provides an electronic device, which includes a processor and a memory. The memory stores at least one instruction or at least one program, which is loaded and executed by the processor to implement the method provided in any of the above embodiments.

[0095] Implementing the technical solution of the present invention can produce at least the following beneficial effects: 1. The rack end protection method and device proposed in this embodiment of the invention, when the rack end protection function is activated, analyzes the current driving speed of the vehicle and the current rotation speed and current angle of the vehicle's steering wheel to obtain a first protection torque and a second protection torque, and further analyzes and processes them to obtain an assist torque for protecting the rack end, thereby improving the flexibility and timeliness of protecting the rack end according to the current state of the vehicle's steering wheel, and improving the accuracy of applying rack end protection.

[0096] 2. The rack end protection method proposed in this embodiment of the invention, by introducing a first angle threshold and a second angle threshold, increases the consideration of the influence of vehicle structural factors and current vehicle speed on the rack end protection function. It obtains the activation angle by analyzing the soft stop angle of the vehicle's steering wheel and the first and second angle thresholds. Using the activation angle as a reference, it analyzes the current angle of the vehicle's steering wheel to determine whether the current steering wheel is in the rack end protection function activated state. This changes the angle at which the rack end protection function is activated from the soft stop angle to a smaller activation angle, thereby increasing the activation range of the end function protection, enhancing the protection strength of the rack end protection function, further reducing the possibility of collision between the rack end and the steering gear housing, improving the driver's steering feel, and improving the accuracy and timeliness of determining the rack end protection function activation state.

[0097] 3. The rack end protection method proposed in this embodiment of the invention compares the current angle and the activation angle, and determines whether the current position of the rack is in a position that activates the rack end protection function based on the angle relationship of the steering wheel. This improves the simplicity and efficiency of the rack state judgment method, thereby enabling an immediate response when the rack position approaches the rack end, and enhancing the ability to react to possible collisions with the rack.

[0098] 4. The rack end protection method proposed in this embodiment of the invention determines a first protection torque that varies quadratically with respect to the relative angle between the current angle and the activation angle of the steering wheel when the rack end protection function is activated, thereby improving the controllability of rack end protection and the accuracy of determining the torque to be applied to protect the rack end.

[0099] 5. The rack end protection method proposed in this embodiment of the invention analyzes the current rotation speed of the steering wheel to determine the magnitude of the second protection torque adapted to the current steering wheel state, thereby determining the assist torque output by the motor. This improves the immediacy and flexibility of rack end protection, making the rack end protection scheme more closely related to the current steering wheel state, thereby improving the adaptability of the rack end protection function in multiple states and optimizing the driver's feel for steering wheel operation.

[0100] 6. The rack end protection method proposed in this embodiment of the invention adjusts the torque output by the motor and determines the first angle threshold and the second angle threshold through simulation, thereby determining the activation angle representing the activation state of the rack end protection function. This shortens the time to enter the activation state of the rack end protection function and enhances the protection strength of the rack end. Furthermore, by determining different second angle thresholds based on the current vehicle speed, different activation angles can be determined, which can improve the accuracy and flexibility of rack end protection.

[0101] 7. The rack end protection method proposed in this embodiment of the invention improves the consistency of the feel change pattern on the left and right sides of the rack zero position by taking positive values ​​for the soft stop angle, the first angle threshold, and the second angle threshold during calculation, and then judging the sign after calculating the first protection torque and the second protection torque. This reduces the complexity of the calculation process, optimizes the direction judgment method, and improves the driving feel.

[0102] 8. The rack end protection method proposed in this embodiment of the invention calculates the change in motor assist torque by superimposing the first protection torque and the second protection torque with the torques of other functional modules. This improves the accuracy of controlling the amount of motor assist when approaching the rack end, thereby preventing mechanical wear and impact between the rack end and the steering gear housing, reducing the difficulty of controlling the output assist torque of the motor, and improving the driving feel near the rack end.

[0103] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, specific embodiments have been described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in a different order than that shown in the embodiments and still achieve the desired result. Additionally, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0104] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the device and server embodiments are basically similar to the method embodiments, so the descriptions are relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0105] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware, or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0106] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for protecting the end of a rack, characterized in that, The method includes: Get the current steering wheel angle, the current vehicle speed, and the current steering wheel rotation speed; The soft stop angle, a first angle threshold, and a second angle threshold are obtained. The soft stop angle is the angle of the steering wheel corresponding to the soft stop. The soft stop is a point that has a preset distance between itself and the mechanical end of the vehicle's rack. The first angle threshold is obtained by angle calibration processing based on the vehicle's structural information, and the second angle threshold is obtained by angle calibration processing based on the vehicle's historical driving speed. The first angle threshold, the second angle threshold, and the soft stop angle are subjected to activation angle analysis to determine the steering wheel activation angle. Based on the current angle and the steering wheel activation angle, analyze the rack end protection function status to determine the current rack end protection function status. If the current rack end protection function of the vehicle is determined to be active, the assist torque limit value of the vehicle's motor is obtained; torque analysis is performed based on the relative angle between the current angle and the steering wheel activation angle where the rack end protection function is active, to determine a first protection torque that varies with a quadratic curve relative to the relative angle; the steering wheel activation angle is obtained by angle analysis of the current driving speed; the process of determining the first protection torque that varies with a quadratic curve relative to the relative angle based on the relative angle includes: summing the result of the square of the relative angle with the relative angle to obtain a first value; summing the result of the square of the second angle threshold with the second angle threshold to obtain a second value; and multiplying the ratio of the first value to the second value with the assist torque limit value to determine the first protection torque that varies with a quadratic curve relative to the relative angle. Obtain the steering wheel speed limit value; The damping coefficient corresponding to the relative angle is determined based on the relative angle. The torque analysis is performed based on the current steering wheel speed of the vehicle to obtain a second protective torque that is linearly related to the current steering wheel speed. This process includes: using the ratio of the current steering wheel speed to the speed limit value as a first multiplier; multiplying the first multiplier, the damping coefficient, and the assist torque limit value to obtain a second multiplier; and generating a second protective torque that is linearly related to the current steering wheel speed based on the second multiplier. After determining the direction, the first and second protection torques are subjected to torque analysis to obtain the assist torque. The assist torque is the torque requested by the motor to output to the power steering system when the end protection function is activated. The assist torque is used to protect the end of the rack.

2. The method according to claim 1, characterized in that, The step of analyzing the rack end protection function status based on the current angle and the steering wheel activation angle to determine the current rack end protection function status includes: Compare the current angle with the steering wheel activation angle to obtain the angle comparison result; If the angle comparison result indicates that the current angle is less than or equal to the steering wheel activation angle, the current rack end protection function is determined to be inactive. If the angle comparison result indicates that the current angle is greater than the steering wheel activation angle, the current rack end protection function is determined to be activated.

3. The method according to claim 1, characterized in that, The step of performing activation angle analysis on the first angle threshold, the second angle threshold, and the soft stop angle to determine the steering wheel activation angle includes: The difference between the soft stop angle and the first angle threshold is taken as the first difference; The difference between the first difference and the second angle threshold is determined as the steering wheel activation angle.

4. The method according to claim 1, characterized in that, Before performing torque analysis on the first and second protective torques after determining their directions to obtain the assist torque, the method further includes: The direction of the first protective torque is determined by performing directional analysis based on the direction of the vehicle's current angle. The direction of the second protective torque is determined by performing directional analysis based on the direction of the vehicle's current rotational speed.

5. The method according to claim 1, characterized in that, The torque analysis processing performed on the first and second protective torques after determining the direction yields the assist torque, including: The first and second protective torques, after the direction is determined, are superimposed to obtain the end-protection torque of the rack output by the end-protection function module; the rack is the output end of the end-protection function module. Obtain the torque output from other functional modules; the other functional modules are modules other than the end protection functional module; The end protection torque of the rack output by the end protection function module is superimposed with the torque output by other function modules to obtain the assist torque; The end protection torque refers to the reduced output torque of the motor to protect the end of the rack.

6. A rack end protection device, characterized in that, The device includes: The parameter acquisition module is used to acquire the current angle of the vehicle's steering wheel, the current speed of the vehicle, and the current rotation speed of the vehicle's steering wheel. An angle acquisition module is used to acquire the soft stop angle, a first angle threshold, and a second angle threshold; the soft stop angle is the angle of the steering wheel corresponding to the soft stop, the soft stop is a point that has a preset distance between itself and the mechanical end of the vehicle's rack, the first angle threshold is obtained by angle calibration processing based on the vehicle's structural information, and the second angle threshold is obtained by angle calibration processing based on the vehicle's historical driving speed. The activation angle determination module is used to perform activation angle analysis processing on the first angle threshold, the second angle threshold and the soft stop angle to determine the steering wheel activation angle. The rack end protection function status determination module is used to analyze the rack end protection function status based on the current angle and the steering wheel activation angle, and determine the current rack end protection function status. A torque limit value acquisition module is used to acquire the assist torque limit value of the vehicle's motor. The first protective torque analysis module is used to determine a first protective torque that varies quadratically with the relative angle between the current angle and the steering wheel activation angle when the rack end protection function of the vehicle is determined to be active. The steering wheel activation angle is obtained by performing angle analysis on the current driving speed. The process of determining the first protective torque that varies quadratically with the relative angle includes: summing the result of the square of the relative angle with the relative angle to obtain a first value; summing the result of the square of the second angle threshold with the second angle threshold to obtain a second value; and multiplying the ratio of the first value to the second value by the power assist torque limit value to determine the first protective torque that varies quadratically with the relative angle. The speed limit value acquisition module is used to acquire the speed limit value of the steering wheel; A damping coefficient determination module is used to determine the damping coefficient corresponding to the relative angle based on the relative angle. The second protective torque analysis module is used to perform torque analysis processing based on the current rotational speed of the vehicle's steering wheel to obtain a second protective torque that is linearly related to the current rotational speed. The process of performing torque analysis processing based on the current rotational speed of the vehicle's steering wheel to obtain the second protective torque that is linearly related to the current rotational speed includes: using the ratio of the current rotational speed of the vehicle's steering wheel to the rotational speed limit value as a first multiplier; multiplying the first multiplier, the damping coefficient, and the assist torque limit value to obtain a second multiplier; and generating a second protective torque that is linearly related to the current rotational speed based on the second multiplier. The assist torque analysis module is used to perform torque analysis on the first and second protection torques after the direction is determined, and obtain the assist torque. The assist torque refers to the torque requested by the motor to output to the power steering system when the rack end protection function is activated, which is used to protect the rack end.

7. An electronic device, characterized in that, The device includes a processor and a memory, the memory storing at least one instruction or at least one program, the at least one instruction or the at least one program being loaded by the processor and executed as described in any one of claims 1-5.

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