WEAR DETERMINATION SYSTEM, WEAR DETERMINATION DEVICE AND INFORMATION TRANSMISSION DEVICE

Abstract

A wear determination system determines the wear of a target wheel, which is a steered wheel on a vehicle. The wear determination system calculates the ground speed of the target wheel and the rotational speed of the target wheel in the same section during a right or left turn of the vehicle and calculates a turning wheel radius based on the ground speed and rotational speed. The turning wheel radius is a dynamic load radius of the target wheel during a right or left turn of the vehicle. The wear determination system determines the wear of a shoulder area of ​​the target wheel based on the turning wheel radius.

Description

REFERENCE TO RELATED REGISTRATIONS

[0001] This application is based on Japanese patent application No. 2024-069109, filed on April 22, 2024, the entire contents of which are hereby incorporated by reference, and claims priority therefrom. BACKGROUND 1. Area

[0002] The present disclosure relates to a wear determination system, a wear determination device and an information transmission device. 2. Description of the state of the art

[0003] Japanese patent publication No. 2021-172280 describes a wear determination system. This wear determination system determines the wear of a wheel based on the distance the wheel has traveled while a vehicle is in motion and the number of revolutions the wheel has made during that distance.

[0004] The wheel has a tread area that contacts the ground when the vehicle travels straight ahead and shoulder areas that contact the ground when the vehicle turns right or left. The wear determination system described in the aforementioned publication does not differentiate between the tread area and the shoulder areas when determining the degree of wear. Therefore, the wear determination system described in the aforementioned publication cannot rely on the wheel's shoulder areas to determine wear. SUMMARY

[0005] This summary serves to present a selection of concepts in simplified form, which are explained in more detail below. This summary is neither intended to identify essential features or characteristics of the claimed subject matter, nor is it intended to serve as an aid in determining the scope of the claimed subject matter.

[0006] In its first general aspect, a wear determination system determines the wear of a target wheel, which is a steered wheel on a vehicle. The wear determination system is designed to calculate the ground speed and rotational speed of the target wheel. These speeds are obtained in the same section during a right or left turn of the vehicle. The wear determination system is also designed to calculate a turning radius based on the ground speed and rotational speed, which represents the dynamic load radius of the target wheel during the right or left turn. Furthermore, the wear determination system is designed to determine the wear of a shoulder area of ​​the target wheel based on this turning radius.

[0007] In a second general aspect, a wear determination device determines the wear of a target wheel, which is a steered wheel on a vehicle. The wear determination device is configured to determine the wear of a shoulder area of ​​the target wheel based on a turning wheel radius, which is a dynamic load radius of the target wheel corresponding to the vehicle turning right or left. The turning wheel radius is calculated based on a ground speed and a rotational speed of the target wheel, which are obtained in the same section during the right or left turn of the vehicle (10).

[0008] In a third general aspect, an information transmission device is configured to communicate with the wear determination device according to the second general aspect. The information transmission device is configured to calculate the ground speed and rotational speed of the target wheel, which are present in the same section during the vehicle's right or left turn, and to calculate the turning wheel radius based on the ground speed and rotational speed, and to transmit this turning wheel radius to the wear determination device.

[0009] Further features and aspects will become apparent from the following detailed description, the drawings, and the claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a schematic representation showing a configuration of a wear determination system according to one embodiment. Fig. Figure 2 is a representation showing a wheel attached to a vehicle. Fig. Figure 3 is a representation showing the state of a steered wheel of the vehicle when the vehicle is traveling straight ahead. Fig. Figure 4 is a representation showing the state of the steered wheel of the vehicle when the vehicle turns right. Fig. 5 is a flowchart that describes a communication mode for determining the steering angle of a steering wheel installed in the vehicle within the wear determination system. Fig. 1 illustrates. Fig. Figure 6 is a diagram illustrating an example of a change in the steering angle of the steering wheel according to an action by the driver of the vehicle. Fig. 7 is a flowchart showing the processes for the wear determination system. Fig. 1 represents the calculation of a straight-running wheel radius of a target wheel. Fig. 8 is a flowchart showing the processes for the wear determination system. Fig. 1 represents the calculation of a wheel radius of the target wheel when running along a curve. Fig. Figure 9 is a representation that shows a relationship between a steering center and a steering angle of the vehicle's steered wheels when the vehicle turns right. Fig. Figure 10 is a flowchart that describes a communication mode for a wear determination device for determining the wear of a shoulder area of ​​the target wheel in the wear determination system. Fig. 1 illustrates. Fig. Table 11 illustrates an example of information transmitted from an information transfer device to the wear determination device in the wear determination system of Fig. 1 will be transferred. Fig. Figure 12 is a flowchart that represents a communication mode for the wear determination device for determining the wear of the shoulder area of ​​the target wheel in the wear determination system of a first modification.

[0010] In the drawings and detailed descriptions, identical reference symbols refer to identical elements. The drawings may not be to scale, and the relative size, proportions, and representation of elements in the drawings may be exaggerated for clarity, illustration, and simplification. DETAILED DESCRIPTION

[0011] This description provides a comprehensive understanding of the described procedures, devices, and / or systems. Modifications and equivalents of the described procedures, devices, and / or systems are obvious to a person of average competence. The sequence of operations is exemplary and may be modified by a person of average competence, except for operations that must necessarily be performed in a specific order. Descriptions of functions and designs that are known to a person of average competence may be omitted.

[0012] Exemplary embodiments can take various forms and are not limited to the examples described. However, the examples described are thorough and complete and convey the full scope of the disclosure to an average person with expertise in the field.

[0013] In this description, “at least one of A and B” should be understood to mean “only A, only B or both A and B”.

[0014] The following describes a wear determination system according to one embodiment with reference to the Fig. 1 to 11 described. Configuration of the wear detection system 100

[0015] As in Fig. Figure 1 shows a wear determination system 100 comprising a vehicle 10 and a wear determination device 25.

[0016] As in Fig. As shown in Figure 1, the vehicle 10 has an information transmission device 11. The information transmission device 11 has an electronic brake control unit 12 (brake ECU) and a communication device 13.

[0017] The electronic brake control unit 12 is an electronic control device that controls the brakes contained in the vehicle 10. The electronic brake control unit 12 generates information about the vehicle 10 based on information from several sensors contained in the vehicle 10.

[0018] The electronic brake control unit 12 has a storage device 33 in which programs are stored, and a processing circuit 32 which executes the programs stored in the storage device 33 and performs various operations. The processing circuit 32 has a processor.

[0019] The information transmission device 11 can be connected to the wear detection device 25 either wired or wirelessly. The communication device 13 transmits information about the vehicle 10, generated by the electronic brake control unit 12, to the wear detection device 25. In this way, the information transmission device 11 transmits the information about the vehicle 10 to the wear detection device 25. The information transmitted by the information transmission device 11 will be described later.

[0020] The electronic brake control unit 12 obtains information from a steering angle sensor 14, a yaw rate sensor 15, a speed sensor 16 and wheel speed sensors to generate the information about the vehicle 10.

[0021] The steering angle sensor 14 measures the steering angle of the vehicle's steering wheel 10. The steering angle sensor 14 transmits the measured steering angle to the electronic brake control unit 12.

[0022] The yaw rate sensor 15 measures the yaw rate of the vehicle 10. The yaw rate sensor 15 transmits the measured yaw rate to the electronic brake control unit 12.

[0023] The speed sensor 16 measures the vehicle's speed 10. Specifically, the speed sensor 16 measures the vehicle's speed 10 based on the rotational speed of a crankshaft, transmission, engine, or similar drive mechanism. The speed sensor 16 transmits the measured vehicle speed 10 to the electronic brake control unit 12.

[0024] As in Fig. As shown in Figure 1, the vehicle 10 has four wheel speed sensors, namely a left front wheel speed sensor 17, a right front wheel speed sensor 18, a left rear wheel speed sensor 19 and a right rear wheel speed sensor 20.

[0025] The left front wheel speed sensor 17 measures the rotational speed of a left front wheel 21. The left front wheel 21 is located on the front left side of the vehicle 10. The left front wheel speed sensor 17 transmits the measured rotational speed of the left front wheel 21 to the electronic brake control unit 12.

[0026] The right front wheel speed sensor 18 measures the rotational speed of a right front wheel 22. The right front wheel 22 is located on the front right side of the vehicle 10. The right front wheel speed sensor 18 transmits the measured rotational speed of the right front wheel 22 to the electronic brake control unit 12.

[0027] The left rear wheel speed sensor 19 measures the rotational speed of a left rear wheel 23. The left rear wheel 23 is located on the rear left side of the vehicle 10. The left rear wheel speed sensor 19 transmits the measured rotational speed of the left rear wheel 23 to the electronic brake control unit 12.

[0028] The right rear wheel speed sensor 20 measures the rotational speed of a right rear wheel 24. The right rear wheel 24 is located on the rear right side of the vehicle 10. The right rear wheel speed sensor 20 transmits the measured rotational speed of the right rear wheel 24 to the electronic brake control unit 12.

[0029] As in Fig. As shown in Figure 1, the wear detection device 25 has a storage device 27 in which programs are stored, and a processing circuit 26 which executes the programs stored in the storage device 27 and performs various operations. The processing circuit 26 has a processor. The wear detection device 25 is, for example, a server installed outside the vehicle 10.

[0030] Both the processing circuit 26 and the processing circuit 32 can each include one or more dedicated hardware circuits, such as an application-specific integrated circuit (ASIC), which executes at least some of the steps of different processes. Alternatively, both the processing circuit 26 and the processing circuit 32 can include a combination of one or more processors and one or more dedicated hardware circuits. Each processor can include a main processor (CPU) and memory modules such as random-access memory (RAM) and read-only memory (ROM). The memory modules can store program code or instructions designed to cause the main processor to execute processes. The memory modules, i.e., computer-readable media, include all available media that a general-purpose or specialized computer can access. Overview of the shoulder areas 29 of the target wheel

[0031] The wear determination device 25 determines the wear of the shoulder areas 29 of the target wheel based on the information about the vehicle 10 received by the information transmission device 11.

[0032] The target wheel is a wheel that the wear detection device 25 and the wear detection system 100 are directed toward determining. The wear detection device 25 and the wear detection system 100 are directed toward determining a steered wheel attached to the vehicle 10. The steered wheels of the vehicle 10 are the left front wheel 21 and the right front wheel 22. The target wheels of the wear detection device 25 and the wear detection system 100 are the left front wheel 21 and the right front wheel 22.

[0033] Fig. Figure 2 shows a target wheel attached to vehicle 10. The one in Fig. The wheel shown in Figure 2 is, for example, the left front wheel 21. As in Fig. As shown in Figure 2, the target wheel has a tread area 28 and shoulder areas 29. The shoulder areas 29 include one shoulder area 29 on the right side (in the direction of travel) and one shoulder area 29 on the left side (in the direction of travel). In the following description, the shoulder area 29 on the right side (in the direction of travel) is simply referred to as the right shoulder area 29, and the shoulder area 29 on the left side (in the direction of travel) is simply referred to as the left shoulder area 29.

[0034] When the vehicle travels straight ahead 10, the tread area 28 touches the ground under the target wheel. Fig. Figure 3 shows the state of the target wheel when the vehicle is traveling straight ahead. This is shown in Fig. The wheel shown in point 3 is, for example, the left front wheel 21.

[0035] When the vehicle steers 10 to the right, the target wheel tilts towards the ground according to the target wheel's steering angle, thus changing the area where the target wheel contacts the ground. As long as the target wheel's steering angle is less than a specific angle, part of the target wheel between the tread area 28 and the right shoulder area 29 contacts the ground. If the target wheel's steering angle is greater than the specific angle, the right shoulder area 29 contacts the ground.

[0036] Fig. Figure 4 shows a state of the target wheel when the vehicle turns right (10), where the steering angle of the target wheel is greater than the specific angle. The in Fig. The wheel shown in Figure 4 is, for example, the left front wheel 21. When the vehicle turns right at 10, the target wheel is tilted to the right relative to the ground, as shown in Figure 4. Fig. Figure 4 shows that if the steering angle of the target wheel is greater than the specific angle, the right shoulder area 29 touches the ground.

[0037] When the vehicle 10 steers to the left, the area where the target wheel contacts the ground changes according to the steering angle of the target wheel, similar to when the vehicle 10 steers to the right. As long as the steering angle of the target wheel is smaller than the specific angle, part of the target wheel between the tread area 28 and the left shoulder area 29 contacts the ground. If the steering angle of the target wheel is larger than the specific angle, the left shoulder area 29 contacts the ground.

[0038] The designation “a1” in Fig. Figure 3 indicates a straight-running wheel radius of the target wheel. The straight-running wheel radius is a dynamic load radius of the target wheel when the vehicle is traveling straight ahead.

[0039] The designation “a2” in Fig. Figure 4 indicates the turning radius of the target wheel. The turning radius is a dynamic load radius of the target wheel when the vehicle turns right or left (10).

[0040] The more the shoulder areas 29 of the target wheel wear, the smaller the turning radius of the wheel becomes. The wear detection device 25 determines the wear of the shoulder areas 29 of the target wheel based on the turning radius of the wheel. Communication mode for calculating the straight-line wheel radius and the curve-bound wheel radius

[0041] The information transmission device 11 transmits information specifying the straight-line wheel radius and the cornering wheel radius to the vehicle 10. As described above, the electronic brake control unit 12 generates the information about the vehicle 10. The electronic brake control unit 12 calculates the straight-line wheel radius and the cornering wheel radius based on information from several sensors contained in the vehicle 10, thereby generating the information about the vehicle 10.

[0042] Fig. Figure 5 illustrates a communication mode executed by the electronic brake control unit 12 to calculate the straight-line wheel radius and the cornering wheel radius. Fig. 5. The processes executed by the electronic brake control unit 12 are carried out by the processing circuit 32.

[0043] The electronic brake control unit 12 calculates the straight-line wheel radius and the cornering wheel radius based on values ​​measured by several sensors contained in the vehicle 10 within a calculation period. The calculation period is a specific time interval within the time during which the vehicle 10 is in motion.

[0044] As in Fig. As shown in Figure 5, the steering angle sensor 14 transmits information indicating the steering angle of the steering wheel as determined by the driver of the vehicle 10 to the electronic brake control unit 12. The steering angle sensor 14 transmits information indicating the change in the steering angle of the steering wheel during the calculation period to the electronic brake control unit 12. In the following drawings, the value of the steering angle specified by the information transmitted by the steering angle sensor 14 is expressed as δ.

[0045] As in Fig. As shown in Figure 5, the electronic brake control unit 12, which has received the steering angle information from the steering angle sensor 14, performs a steering angle determination procedure. This procedure divides the computation time based on the steering angle specified by the information received from the steering angle sensor 14.

[0046] Fig. Figure 6 shows the change in the steering angle of the steering wheel within the calculation period, as indicated by the information received from the steering angle sensor 14 by the electronic brake control unit 12.

[0047] In the diagram of Fig. Figure 6 represents the vertical axis of the steering wheel, measured by the steering angle sensor 14. In the diagram of Fig. In figure 6, the horizontal axis represents time.

[0048] In the diagram of Fig. 6. During a period of time in which the steering angle is zero, the steering wheel is neither turned left nor right. In the diagram of Fig. 6. The steering wheel is turned to the right during a time period in which the steering angle is above the horizontal axis. In the diagram in Fig. 6. The steering wheel is turned to the left during a period of time in which the steering angle is below the horizontal axis.

[0049] In the steering angle determination procedure, the electronic brake control unit 12 divides the calculation time period into an X-time period and a Y-time period, which are in Fig. 6 are marked.

[0050] The in Fig. The X-time interval shown in Figure 6 is a time interval in which the steering angle of the steering wheel is greater than or equal to 0 degrees and less than 90 degrees. The [information about the X-time interval shown in Figure 6 is missing from the original text.] Fig. The Y-time span shown in Figure 6 is a time span in which the steering angle of the steering wheel is greater than or equal to 90 degrees.

[0051] As in Fig. As shown in Figure 5, after the steering angle determination procedure has been carried out, the electronic brake control unit 12 performs various procedures according to the type of time period.

[0052] As in Fig. As shown in Figure 5, the electronic brake control unit 12 calculates the straight-ahead wheel radius based on information measured by several sensors in the vehicle 10 during a time interval in which the steering angle of the steering wheel is greater than or equal to 0 degrees and less than 90 degrees. That is, the electronic brake control unit 12 calculates the straight-ahead wheel radius based on information measured by the sensors in the vehicle 10 during the X-time interval. In the present embodiment, the wear detection system 100 determines that the vehicle 10 is traveling straight ahead when the steering angle of the steering wheel is greater than or equal to 0 degrees and less than 90 degrees.

[0053] As in Fig. As shown in Figure 5, the electronic brake control unit 12 calculates the turning wheel radius based on information measured by several sensors in the vehicle 10 during a time interval in which the steering wheel angle is greater than or equal to 90 degrees. That is, the electronic brake control unit 12 calculates the turning wheel radius based on information measured by the sensors in the vehicle 10 during the Y-time interval. In the present embodiment, the wear detection system 100 determines that the vehicle 10 turns right or left when the steering wheel angle is greater than or equal to 90 degrees. Mode of the executed procedure for calculating the straight-running wheel radius

[0054] Fig. Figure 7 shows a series of procedures executed by the electronic brake control unit 12 to calculate the straight-line wheel radius. After executing the procedure in Fig. In the steering angle determination procedure shown in section 5, the electronic brake control unit 12 performs a series of actions based on information measured by several sensors in the vehicle 10 during the X-time span. Fig. The processes shown in the 7 diagrams are based on this. Fig. The sequence of processes shown in Figure 7 is executed by the processing circuit 32.

[0055] As described above, the target wheels are the left front wheel 21 and the right front wheel 22. The electronic brake control unit 12 executes a series of commands for both the left front wheel 21 and the right front wheel 22. Fig. The processes shown in section 7 are described below. A first case is described below in which the electronic brake control unit 12 calculates the straight-line wheel radius of the left front wheel 21, whereby... Fig. Reference is made to this.

[0056] During step S10, the electronic brake control unit 12 calculates a ground speed of the target wheel, which occurs while the vehicle 10 is traveling straight ahead. In the first case, the electronic brake control unit 12 calculates the ground speed of the left front wheel 21 while the vehicle 10 is traveling straight ahead.

[0057] To calculate the ground speed of the left front wheel 21 while the vehicle 10 is traveling straight ahead, the electronic brake control unit 12 stores the radius of a non-target wheel, i.e., a non-target wheel belonging to the wheels of the vehicle 10. The electronic brake control unit 12 stores an average of the radii of the left rear wheel 23 and the right rear wheel 24 as the radius of the non-target wheel.

[0058] To calculate the ground speed of the left front wheel 21, which is present while the vehicle 10 is traveling straight ahead, the electronic brake control unit 12 obtains the rotational speed during the X-time interval for one of the wheels belonging to the vehicle 10 that is not a target wheel. The electronic brake control unit 12 obtains an average of the rotational speeds of the left rear wheel 23 and the right rear wheel 24 during the X-time interval as the rotational speed of the non-target wheel. The electronic brake control unit 12 obtains the rotational speed of the left rear wheel 23 during the X-time interval from the left rear wheel speed sensor 19. The electronic brake control unit 12 obtains the rotational speed of the right rear wheel 24 during the X-time interval from the right rear wheel speed sensor 20.

[0059] The ground speed of the target wheel during the straight-ahead movement of vehicle 10 is equal to the ground speed of the non-target wheel. Assume that, during straight-ahead movement of vehicle 10, the ground speed of the left front wheel 21 V1, the mean of the radii of the left rear wheel 23 and the right rear wheel 24 is r, and the mean of the rotational speeds of the left rear wheel 23 and the right rear wheel 24 during the time interval of Fig. If 6 N is the case, the following relationship applies. V1=2πr×N

[0060] In this way, the electronic brake control unit 12 calculates the ground speed of the left front wheel 21, which is present during the straight-ahead driving of the vehicle 10.

[0061] During step S11, the electronic brake control unit 12 calculates an angular velocity of the target wheel 21, which is present while the vehicle 10 is traveling straight ahead. In the first case, the electronic brake control unit 12 calculates the angular velocity of the left front wheel 21, which is present while the vehicle 10 is traveling straight ahead.

[0062] The electronic brake control unit 12 obtains the rotational speed of the left front wheel 21 in the X-time interval from the left front wheel speed sensor 17 in order to calculate the angular velocity of the left front wheel 21, which is present during the straight-ahead driving of the vehicle 10.

[0063] Assuming that when the vehicle 10 travels straight ahead, the angular velocity of the left front wheel 21 is ω1 and the rotational speed of the left front wheel 21 in the X-time interval N1 is, the following relationship applies. ω1=2π×N1

[0064] In this way, the electronic brake control unit 12 calculates the angular velocity of the left front wheel 21, which is present during the straight-ahead driving of the vehicle 10.

[0065] During step S12, the electronic brake control unit 12 calculates the straight-line wheel radius of the target wheel. In the first case, the electronic brake control unit 12 calculates the straight-line wheel radius of the left front wheel 21.

[0066] Assuming that the straight-running wheel radius of the left front wheel 21 is b1, the following relationship applies. b1=V1ω1

[0067] In this way, the electronic brake control unit 12 calculates the straight-running wheel radius of the left front wheel 21.

[0068] The wear determination system 100 calculates the straight-running wheel radius based on the ground speed of the target wheel and the rotational speed of the target wheel, which are obtained in the same section in which the vehicle 10 travels straight ahead. Overview of the determination time interval extraction method

[0069] Fig. Figure 8 shows a series of procedures executed by the electronic brake control unit 12 to calculate the wheel radius when cornering. After executing the procedure in Fig. In the steering angle determination procedure shown in section 5, the electronic brake control unit 12 performs a series of actions based on information measured by several sensors contained in the vehicle 10 during the “Y” time interval. Fig. The processes shown in the 8 are described below. Fig. The series of processes shown in Figure 8 is executed by the processing circuit 32.

[0070] The electronic brake control unit 12 calculates the cornering wheel radius for both the right shoulder area 29 and the left shoulder area 29 of the left front wheel 21. The electronic brake control unit 12 calculates the cornering wheel radius for both the right shoulder area 29 and the left shoulder area 29 of the right front wheel 22. The electronic brake control unit 12 executes the in Fig. 8 shown series of processes for each shoulder area 29 of the target wheel.

[0071] During step S20, the electronic brake control unit 12 performs a time-span extraction procedure. This time-span extraction procedure is a method for extracting a time span from the Y-time span to calculate the wheel radius as it travels in a curve.

[0072] The electronic brake control unit 12 extracts a time period in which the following three conditions are met as a time period for calculating the wheel radius when cornering.

[0073] The first condition is that the steering angle of the target wheel is relatively large. As described later, the electronic brake control unit 12 uses the ground speed of the target wheel, which is present during the right or left turn of the vehicle 10, to calculate the turning wheel radius. As can be seen from the Fig. As described in sections 2 to 4, the shoulder areas 29 of the target wheel touch the ground when the target wheel's steering angle is greater than the specific angle. The turning wheel radius, calculated based on the target wheel's ground velocity at a steering angle smaller than the specific angle, may not accurately reflect the degree of wear on the target wheel's shoulder areas 29.

[0074] The electronic brake control unit 12 extracts a time interval during which the steering angle of the left front wheel 21 is greater than a predetermined angular reference value, as the time interval for calculating the turning wheel radius. In the present embodiment, but not limited thereto, the angular reference value is the steering angle of the target wheel that occurs when the steering angle of the vehicle's steering wheel 10 is 180 degrees.

[0075] The steering angle of the target wheel relative to the steering angle of the steering wheel differs between the left front wheel 21 and the right front wheel 22. The steering angle of the target wheel relative to the steering angle of the steering wheel also differs depending on whether the steering wheel is turned to the left or to the right. Therefore, the angle reference value differs depending on the direction of rotation of the steering wheel and the position of the target wheel.

[0076] The steering angle of the target wheel increases in accordance with the steering angle of the vehicle's steering wheel 10. The electronic brake control unit 12 extracts a time interval in which the steering wheel angle is greater than 180 degrees from the Y-time interval in order to extract a time interval in which the steering angle of the target wheel is greater than the angle reference value. The wear determination system 100 does not calculate the turning wheel radius if the steering angle of the target wheel, which is present during the right or left turn of the vehicle 10, is less than or equal to the angle reference value.

[0077] The second condition is that the steering angle of the target wheel is constant. As described later, the electronic brake control unit 12 calculates the turning radius of the wheel using the steering angle of the target wheel. During a period of time in which the steering angle of the target wheel changes, the electronic brake control unit 12 cannot accurately calculate the turning radius of the wheel.

[0078] The third condition is that the vehicle 10's speed is relatively slow. If the vehicle 10 turns right or left while its speed is high, it will skid. If the vehicle 10 skids, the electronic brake control unit 12 cannot accurately calculate the ground speed of the target wheel.

[0079] The electronic brake control unit 12 extracts a time period in which the movement speed of the vehicle 10, which is present during the right or left turn of the vehicle 10, is less than a predetermined speed reference value, as a time period for calculating the turning wheel radius.

[0080] In the present embodiment, the speed reference value is 15 km / h. The electronic brake control unit 12 extracts a time interval during which the movement speed is lower than the speed reference value from the Y-time interval based on the movement speed of the vehicle 10 received by the speed sensor 16. The wear determination system 100 does not calculate the turning wheel radius if the movement speed of the vehicle 10 during right or left turns is greater than or equal to the speed reference value. The speed reference value is not limited to 15 km / h.

[0081] Two in Fig. 6 Sections enclosed by the dashed lines with long and short dashes correspond to time intervals extracted by the electronic brake control 12 as time intervals for calculating the curve wheel radius.

[0082] As shown by the Fig. As described in Figures 2 to 4, the right shoulder area 29 touches the ground when the vehicle 10 turns right and the steering angle of the target wheel is greater than the specific angle. The wear determination system 100 can determine the wear of the right shoulder area 29 by calculating the turning wheel radius present during the right turn of the vehicle 10. One of the two sections enclosed by the dashed lines with long and short dashes in Fig. 6 corresponds to a right turn determination time span of 30 for calculating the curve radius that is present during the right turn of vehicle 10.

[0083] As shown by the Fig. As described in Figures 2 to 4, the left shoulder area 29 touches the ground when the vehicle 10 turns left and the steering angle of the target wheel is greater than the specific angle. The wear determination system 100 can determine the wear of the left shoulder area 29 by calculating the turning wheel radius present during the left turn of the vehicle 10. The other of the two sections enclosed by the dashed lines with long and short dashes in Fig. 6 corresponds to a left-turn determination time span 31 for calculating the curve radius that is present during the left turn of vehicle 10.

[0084] In step S21, the electronic brake control unit 12 determines whether the extraction of a time span for calculating the curve-running wheel radius in the determination time span extraction procedure of step S20 was successful.

[0085] If there is no time interval within the calculation period that fulfills the three conditions mentioned above, the electronic brake control unit 12 cannot extract a time interval for calculating the cornering wheel radius. The electronic brake control unit 12 determines that the time interval extraction is unsuccessful if the time interval for calculating the cornering wheel radius is not extracted in the time interval extraction procedure.

[0086] If the procedure of Fig. 8 is executed to determine whether the right shoulder area 29 is worn, the electronic brake control unit 12 determines that the extraction of the time span is unsuccessful if the right turn determination time span 30 is not extracted. If the procedure of Fig. 8 is executed to determine the wear of the left shoulder area 29, the electronic brake control unit 12 determines that the extraction of the time span is not successful if the left turn determination time span 31 is not extracted.

[0087] If the electronic brake control unit 12 determines that the extraction of the time period is unsuccessful (step S21: NO), the electronic brake control unit 12 terminates the process in Fig. 8 depicted sequence of processes.

[0088] On the other hand, the electronic brake control unit 12 determines that the time interval extraction is successful if the time interval for calculating the curve radius in the time interval extraction procedure has been extracted. If the electronic brake control unit 12 determines that the time interval extraction is successful (step S21: YES), the electronic brake control unit 12 proceeds to the next step, step S22.

[0089] In the sequences from step S22 onwards, the electronic brake control unit 12 calculates the turning radii of the left front wheel 21 and the right front wheel 22 that are present during the right turn of the vehicle 10, based on the information from the sensors in the right turn determination time span 30. In the sequences from step S22 onwards, the electronic brake control unit 12 calculates the turning radii of the left front wheel 21 and the right front wheel 22 that are present during the left turn of the vehicle 10, based on the information from the sensors in the left turn determination time span 31. Mode of the executed procedure for calculating the wheel radius while cornering

[0090] The following refers to the Fig. 8 and Fig. 9 a second case of calculating the curve radius for the left front wheel 21 belonging to the target wheels of the vehicle 10 is described, which is a case during the right turn of the vehicle 10.

[0091] During step S22, the electronic brake control unit 12 performs a steering angle conversion procedure. The steering angle of the target wheel, which corresponds to the steering angle of the steering wheel in the vehicle 10, is determined in advance. The electronic brake control unit 12 stores a steering angle of a steered wheel that corresponds to the steering angle of the steering wheel in the vehicle 10. In the steering angle conversion procedure, the electronic brake control unit 12 calculates the steering angle of the target wheel in the time period for calculating the turning radius based on the steering angle of the steering wheel in the time period for calculating the turning radius. In the second case, the electronic brake control unit 12 calculates the steering angle of the left front wheel 21 in the right turn determination time period 30 based on the steering angle of the steering wheel in the right turn determination time period 30.

[0092] During step S23, the electronic brake control unit 12 calculates a turning radius of the target wheel, which is present during the right or left turn of the vehicle 10. In the second case, the electronic brake control unit 12 calculates the turning radius of the left front wheel 21, which is present during the right turn of the vehicle 10.

[0093] Fig. Figure 9 illustrates a relationship between a steering center point and the steering angle of the steered wheels at the time the vehicle 10 turns right. Fig. Point O, designated as the steering center, is shown in section 9. Fig. 9 denotes L as a wheelbase length of the vehicle 10.

[0094] In Fig. 9 denotes Ro as the turning radius of the left front wheel 21, which exists during the right turn of the vehicle 10. In Fig. 9 denotes Ri the turning radius of the right front wheel 22, which is present during the right turn of the vehicle 10.

[0095] In Fig. 9 denotes δo the steering angle of the left front wheel 21, which is present during the right turn of the vehicle 10. In Fig. 9 denotes δi the steering angle of the right front wheel 22, which is present during the right turn of the vehicle 10.

[0096] As in Fig. As shown in Figure 9, the angle formed by the straight line connecting the left rear wheel 23 and the right rear wheel 24, and the straight line indicating the turning radius of the left front wheel 21, is equal to the steering angle of the left front wheel 21. As shown in Fig. As shown in Figure 9, the angle formed by the straight line connecting the left rear wheel 23 and the right rear wheel 24, and the straight line indicating the turning radius of the right front wheel 22, is equal to the steering angle of the left front wheel 21.

[0097] Due to the in Fig. The following relationship applies to the relationship shown in 9. Ro=Lsinδo

[0098] In this way, the electronic brake control unit 12 calculates the turning radius of the left front wheel 21, which is present during the right turn of the vehicle 10.

[0099] During step S24, the electronic brake control unit 12 calculates the ground speed of the target wheel during the right or left turn of the vehicle 10. In the second case, the electronic brake control unit 12 calculates the ground speed of the left front wheel 21 during the right turn of the vehicle 10.

[0100] The electronic brake control unit 12 determines the yaw rate of the vehicle 10 in the right turn determination time span 30 from the yaw rate sensor 15 in order to calculate the ground speed of the left front wheel 21, which is present during the right turn of the vehicle 10.

[0101] Assuming that when vehicle 10 turns right, the ground speed of the left front wheel is 21 V2 and the yaw rate of vehicle 10 during the right turn determination time span is 30 Y, the following relationship applies. V2=Ro×Y

[0102] In this way, the electronic brake control unit 12 calculates the ground speed of the left front wheel 21 during the right turn of the vehicle 10. The wear determination system 100 calculates the ground speed of the target wheel during the right or left turn of the vehicle 10, based on the yaw rate of the vehicle 10 and the steering angle of the target wheel, which is achieved in the same section in which the vehicle 10 turns right or left, and the wheelbase length of the vehicle 10.

[0103] During step S25, the electronic brake control unit 12 calculates the angular velocity of the target wheel during the right or left turn of the vehicle 10. In the second case, the electronic brake control unit 12 calculates the angular velocity of the left front wheel 21 during the right turn of the vehicle 10.

[0104] The electronic brake control unit 12 determines the rotational speed of the left front wheel 21 during the right turn determination time interval 30 from the left front wheel speed sensor 17 in order to calculate the angular velocity of the left front wheel 21 that is present during the right turn of the vehicle 10.

[0105] Assuming that when vehicle 10 turns right, the angular velocity of the left front wheel 21 ω2 and the rotational speed of the left front wheel 21 during the right-turn determination time span 30 N2, then the following relationship applies. ω2=2π×N2

[0106] In this way, the electronic brake control unit 12 calculates the angular velocity of the left front wheel 21, which is present during the right turn of the vehicle 10.

[0107] During step S26, the electronic brake control unit 12 calculates the turning radius of the target wheel. In the second case, the electronic brake control unit 12 calculates the turning radius of the left front wheel 21, which is present during the right turn of the vehicle 10.

[0108] Assuming that when vehicle 10 turns right, the turning radius of the left front wheel is 21 b2, the following relationship applies. b2=V2ω2

[0109] In this way, the electronic brake control unit 12 calculates the turning radius of the left front wheel 21 during the right turn of the vehicle 10. The wear determination system 100 and the information transmission device 11 calculate the turning radius based on the ground speed and rotational speed of the target wheel, which are obtained in the same section in which the vehicle 10 turns right or left. Communication mode for determination by the wear determination device 25

[0110] Fig. Figure 10 illustrates a communication mode used by the wear detection device 25 to determine wear of the shoulder areas 29 of the target wheel. The communication of the in Fig. The mode shown in 10 is activated after executing the communication of the in Fig. The mode shown in section 5 is executed. The communication of the in Fig. The mode shown in section 10 is executed after the processes for calculating the straight-line wheel radius and the curve-running wheel radius have been carried out.

[0111] In Fig. The processes executed by the electronic brake control unit 12 are carried out by the processing circuit 32. Fig. 10. The processes carried out by the wear determination device 25 are carried out by the processing circuit 26.

[0112] As in the upper part of Fig. As shown in Figure 10, the electronic brake control unit 12 transmits information specifying the straight-line wheel radius and the cornering wheel radius to the communication device 13. The communication device 13 transmits the information specifying the straight-line wheel radius and the cornering wheel radius from the electronic brake control unit 12 to the wear detection device 25. The information transmission device 11 transmits the information specifying the straight-line wheel radius and the cornering wheel radius to the wear detection device 25.

[0113] Fig. Figure 11 shows an example of the straight-running wheel radius and the curved-running wheel radius, which are specified by the information transmitted from the information transmission device 11 to the wear determination device 25.

[0114] As with reference to Fig. As described in section 7, the electronic brake control unit 12 transmits information specifying the straight-line wheel radius for both the left front wheel 21 and the right front wheel 22. Fig. 11 is the straight-line wheel radius of the left front wheel 21 b1, calculated by the electronic brake control unit 12. In Fig. 11 is the straight-running wheel radius of the right front wheel 22 c1 calculated by the electronic brake control unit 12.

[0115] As demonstrated by Fig. As described in section 8, the electronic brake control unit 12 calculates the turning wheel radius based on the sensor values ​​during the right turn determination time interval 30 in order to determine the wear of the right shoulder area 29 of the left front wheel 21 and the right front wheel 22. Fig. 11 is the turning radius of the left front wheel 21, which was calculated in the right-turn determination time span 30, b2. In Fig. 11 is the turning wheel radius of the right front wheel 22, which was calculated in the right turn determination time span 30, c2.

[0116] As demonstrated by Fig. As described in section 8, the electronic brake control unit 12 calculates the turning wheel radius based on the sensor values ​​during the left turn determination time interval 31 in order to determine the wear of the left shoulder area 29 of the left front wheel 21 and the right front wheel 22. Fig. 11 is the turning radius of the left front wheel 21, which was calculated in the left-turn determination time span 31, b3. In Fig. 11 is the curve radius of the right front wheel 22, which was calculated in the left turn determination time span 31, c3.

[0117] As in the upper part of Fig. As shown in Figure 10, the electronic brake control unit 12 transmits the information specifying the straight-line wheel radius and the cornering wheel radius to the communication device 13 if both the straight-line wheel radius and the cornering wheel radius have been calculated. If the straight-line wheel radius or the cornering wheel radius has not been calculated, the electronic brake control unit 12 transmits neither the information specifying the straight-line wheel radius nor the information specifying the cornering wheel radius.

[0118] In the Fig. In the steering angle determination method shown in section 5, the electronic brake control unit 12 can, if the steering angle of the steering wheel is greater than or equal to 0 degrees and does not fall below 90 degrees during the calculation period, select b1 and c1 from Fig. Calculate 11. In the Fig. In the determination time span extraction method 8 shown, the electronic brake control unit 12 can extract b2 and c2 from the right turn determination time span 30 if the right turn determination time span 30 is not extracted. Fig. Do not calculate 11. In the Fig. In the determination time span extraction method shown in section 8, the electronic brake control unit 12 can extract b3 and c3 from the left turn determination time span 31 if the left turn determination time span 31 is not extracted. Fig. Do not calculate 11.

[0119] When all values ​​b1, b2, b3, c1, c2 and c3 have been calculated, the electronic brake control unit 12 transmits information specifying all calculated values ​​to the wear determination device 25. A configuration can be applied in which, even if the electronic brake control unit 12 cannot calculate the cornering wheel radius present during the right turn of the vehicle 10, the electronic brake control unit 12 transmits information specifying the calculated values ​​to the wear determination device 25, provided that the electronic brake control unit 12 has calculated the cornering wheel radius and the straight-line wheel radius present during the left turn of the vehicle 10.A configuration can be applied in which, even if the electronic brake control unit 12 cannot calculate the cornering wheel radius present during the left turn of the vehicle 10, the electronic brake control unit 12 transmits information indicating the calculated values ​​to the wear determination device 25, provided that the electronic brake control unit 12 has calculated the cornering wheel radius and the straight-line wheel radius present during the right turn of the vehicle 10.

[0120] As in the upper part of Fig. As shown in Figure 10, the wear determination device 25, which has received information specifying the straight-line wheel radius and the curved wheel radius, performs a wear determination procedure. The wear determination procedure is a method for determining the wear of the shoulder areas 29 of the target wheel based on the straight-line wheel radius and the curved wheel radius calculated by the information transmission device 11.

[0121] In the wear determination procedure, the wear determination device 25 monitors a difference between the straight-line wheel radius and the curved wheel radius. The wear determination device 25 monitors a difference between b1 and b2 when determining the wear of the right shoulder area 29 of the left front wheel 21. The wear determination device 25 monitors a difference between b1 and b3 when determining the wear of the left shoulder area 29 of the left front wheel 21. The wear determination device 25 monitors a difference between c1 and c2 when determining the wear of the right shoulder area 29 of the right front wheel 22. The wear determination device 25 monitors a difference between c1 and c3 when determining the wear of the left shoulder area 29 of the right front wheel 22.

[0122] When the shoulder areas 29 are worn, the turning wheel radius decreases to such an extent that the difference between the straight-line wheel radius and the turning wheel radius increases. As in the lower part of Fig. As shown in Figure 10, the wear determination device 25 determines that the shoulder areas 29 of the target wheel are worn when the difference between the straight-running wheel radius and the curved-running wheel radius is greater than or equal to a threshold value.

[0123] The wear detection device 25 determines that the right shoulder area 29 of the left front wheel 21 is worn if the difference between b1 and b2 is greater than or equal to a threshold value. For example, if the difference between b1 and b2 is greater than 2% of b1, the wear detection device 25 determines that the right shoulder area 29 of the left front wheel 21 is worn.

[0124] As described above, the wear determination system 100 calculates the straight-line wheel radius, which is the dynamic load radius of the target wheel during straight-line travel of the vehicle 10. The wear determination system 100 then determines that the shoulder areas 29 of the target wheel are worn if the difference between the cornering wheel radius and the straight-line wheel radius is greater than or equal to the threshold value.

[0125] If the turning wheel radius is significantly smaller than the straight-line wheel radius, the shoulder areas 29 of the target wheel are worn compared to the tread area 28 of the target wheel. This means that if the turning wheel radius is significantly smaller than the straight-line wheel radius, uneven wear occurs in the shoulder areas 29 of the target wheel. The wear detection system 100 can determine particularly effectively that uneven wear has occurred in the shoulder areas 29 of the target wheel.

[0126] The wear determination device 25 similarly determines the wear of the other shoulder area 29 based on the difference between the straight-line wheel radius and the turning wheel radius. The wear determination system 100 determines the wear of the right shoulder area 29 of the target wheel using the turning wheel radius, which is calculated based on the ground speed and rotational speed present during the right turn of the vehicle 10. The wear determination system 100 determines the wear of the left shoulder area 29 of the target wheel using the turning wheel radius, which is calculated based on the ground speed and rotational speed present during the left turn of the vehicle 10.

[0127] As in the lower part of Fig. As shown in Figure 10, after determining the wear of the shoulder areas 29, the wear detection device 25 stores the camber wheel radius received from the information transmission device 11 in the storage device 27. Since the shoulder areas 29 of the target wheel are worn, the camber wheel radius gradually decreases. The change in the camber wheel radius of the target wheel is useful information for confirming the change in the wear progression of the shoulder areas 29 of the target wheel. Since the wear detection device 25 stores the camber wheel radius, it is possible to confirm the change in the camber wheel radius for the target wheel. Operation of the present embodiment

[0128] When the shoulder areas 29 of the target wheel are worn, the turning radius of the target wheel decreases. The wear determination system 100 calculates the turning radius based on the ground speed and the rotational speed of the target wheel during the vehicle 10 turning right or left. The wear determination system 100 determines the wear of the target wheel based on the turning radius. Advantages of the present embodiment (1) The wear determination system 100 can determine the wear of the shoulder areas 29 of the target wheel based on the wheel radius when cornering, which corresponds to the dynamic load radius of the shoulder areas 29 of the target wheel. (2) The wear determination system 100 calculates the ground speed of the target wheel during the right or left turn of the vehicle 10, based on the yaw rate of the vehicle 10 and the steering angle of the target wheel, which is determined in the same section in which the vehicle 10 turns right or left, as well as the wheelbase length of the vehicle 10. This allows the wear determination system 100 to determine the ground speed of the target wheel during the right or left turn of the vehicle 10. (3) The wear determination system 100 calculates the straight-line wheel radius, which is a dynamic load radius of the target wheel while the vehicle 10 is traveling straight ahead. The wear determination system 100 determines that the shoulder areas 29 of the target wheel are worn when the difference between the cornering wheel radius and the straight-line wheel radius is greater than or equal to the threshold value.

[0129] Since the shoulder areas 29 of the target wheel are worn, the dynamic load radius present during right or left turns of the vehicle 10 is smaller than the dynamic load radius present during straight-ahead driving of the vehicle 10. The wear detection system 100 can determine the wear of the shoulder areas 29 of the target wheel by observing the difference between the straight-ahead wheel radius and the turning wheel radius.

[0130] (4) The wear determination system 100 calculates the straight-line wheel radius based on the ground speed and rotational speed of the target wheel achieved in the same section where the vehicle 10 is traveling straight ahead. This allows the wear determination system 100 to calculate the dynamic load radius of the target wheel corresponding to the straight-line vehicle 10.

[0131] (5) The wear determination system 100 does not calculate the wheel radius when cornering if the steering angle of the target wheel is less than or equal to the predetermined angle reference value.

[0132] The shoulder areas 29 of the target wheel contact the ground when the target wheel's steering angle is greater than the specific angle. Therefore, the calculated turning wheel radius, which is based on the target wheel's ground speed at a steering angle smaller than the specific angle, may not accurately reflect the degree of wear on the target wheel's shoulder areas 29.

[0133] The wear determination system 100 calculates the turning wheel radius based on the ground velocity at the steering angle of the target wheel that is greater than the angle reference value. This allows the wear determination system 100 to more accurately determine the wear of the shoulder areas 29 of the target wheel.

[0134] (6) The wear determination system 100 does not calculate the wheel radius when cornering if the speed of the vehicle 10 during the right or left turn of the vehicle 10 is greater than or equal to the predetermined speed reference value.

[0135] If the vehicle 10 turns right or left while traveling at a high speed, it will skid. When the vehicle 10 skids, the wear detection system 100 cannot accurately calculate the wheel's ground speed. The wear detection system 100 calculates the turning wheel radius based on the target wheel's ground speed during the right or left turn, assuming the vehicle 10's speed is low. This allows the wear detection system 100 to more accurately determine the wear on the target wheel's shoulder areas 29.

[0136] (7) The wear determination system 100 determines the wear of the right shoulder area 29 of the target wheel based on the turning wheel radius, which is calculated based on the ground speed and rotational speed present during the right turn of the vehicle 10. The wear determination system 100 determines the wear of the left shoulder area 29 of the target wheel based on the turning wheel radius, which is calculated based on the ground speed and rotational speed present during the left turn of the vehicle 10.

[0137] When the vehicle 10 turns right, the right shoulder area 29 of the target wheel touches the ground. When the vehicle 10 turns left, the left shoulder area 29 of the target wheel touches the ground. The wear detection system 100 modifies the shoulder areas 29, which determine the wear according to the direction of travel of the vehicle 10. This allows the wear detection system 100 to determine the wear of the left and right shoulder areas 29 of the target wheel more accurately.

[0138] (8) The wear determination system 100 comprises the wear determination device 25 and the information transmission device 11. The information transmission device 11 calculates the turning wheel radius based on the ground speed of the target wheel and the rotational speed of the target wheel, which is achieved in the same section during the right or left turn of the vehicle 10. The information transmission device 11 transmits the turning wheel radius to the wear determination device 25. The wear determination device 25 determines the wear of the shoulder areas 29 of the target wheel based on the turning wheel radius.

[0139] In the wear determination system 100, the information transmission device 11 calculates the wheel radius as it travels in curves. In the wear determination system 100, the wear determination device 25 monitors the wheel radius as calculated by the information transmission device 11. This allows the wear determination system 100 to determine the wear of the shoulder areas 29 of the target wheel.

[0140] (9) In the wear determination system 100, the wear determination device 25 includes the storage device 27. The wear determination device 25 stores the wheel radius as it travels along the curve, received from the information transmission device 11, in the storage device 27.

[0141] When the shoulder areas 29 of the target wheel are worn, the turning radius of the wheel gradually decreases. The change in the turning radius of the target wheel is useful information for confirming the change in the wear progression of the shoulder areas 29 of the target wheel.

[0142] In the wear determination system 100, the wear determination device 25 stores the calculated wheel radius for the target wheel. According to the wear determination system 100, it is possible to confirm the change in the wheel radius for the target wheel.

[0143] (10) The wear determination device 25 is directed towards a steered wheel attached to the vehicle 10 as the target wheel for determination purposes. The wear determination device 25 determines the wear of the shoulder areas 29 of the target wheel based on the turning radius of the wheel, which is the dynamic load radius of the target wheel during right or left turns of the vehicle 10. The turning radius of the wheel is calculated based on the ground speed and rotational speed of the target wheel, which are achieved in the same section during the right or left turn of the vehicle 10.

[0144] When the shoulder areas 29 of the target wheel are worn, the dynamic load radius of the target wheel decreases during right or left turns of the vehicle 10. The wear detection device 25 monitors the dynamic load radius of the target wheel during right or left turns of the vehicle 10. This allows the wear detection device 25 to determine the wear of the shoulder areas 29 of the target wheel.

[0145] (11) The information transmission device 11 can communicate with the wear determination device 25. The information transmission device 11 calculates the turning wheel radius, which is the dynamic load radius of the target wheel during right or left turns of the vehicle 10, based on the ground speed and rotational speed of the target wheel attained in the same section during the right or left turn of the vehicle 10. The information transmission device 11 transmits the turning wheel radius to the wear determination device 25.

[0146] The information transmission device 11 calculates the dynamic load radius of the target wheel during right or left turns of the vehicle 10. This allows the information transmission device 11 to instruct the wear determination device 25 to determine the wear of the shoulder areas 29 of the target wheel. Modifications

[0147] The present embodiment can be implemented with the modifications described below. The present embodiment and the following modifications can be implemented in combination to a technically consistent extent.

[0148] In the embodiment above, the wear detection system 100 targets both the left front wheel 21 and the right front wheel 22, which are the steered wheels of the vehicle 10. The wear detection system 100 can target either of the steered wheels of the vehicle 10.

[0149] In the embodiment described above, the vehicle 10 has a yaw rate sensor 15. The electronic brake control unit 12 obtains a yaw rate, which is present during the right or left turn of the vehicle 10, from the yaw rate sensor 15. In the wear detection system 100, the vehicle 10 does not necessarily need to have a yaw rate sensor 15. For example, the electronic brake control unit 12 can obtain the yaw angle by dividing the difference between the ground speed of the left rear wheel 23 and the ground speed of the right rear wheel 24, which is present during the right or left turn of the vehicle 10, by the distance between the left rear wheel 23 and the right rear wheel 24.

[0150] In the embodiment described above, the vehicle 10 has a speed sensor 16. The electronic brake control unit 12 obtains the vehicle 10's speed from the speed sensor 16. In the wear detection system 100, the vehicle 10 does not necessarily need to have a speed sensor 16. The electronic brake control unit 12 can determine the vehicle 10's speed by measuring the ground speed of its wheel. Alternatively, the electronic brake control unit 12 can determine the vehicle 10's speed from its position information.

[0151] The electronic brake control unit 12 according to the above embodiment extracts a time interval in which the steering angle of the target wheel is greater than the angle reference value, as a time interval for calculating the curve-running wheel radius in the determination time interval extraction method of Fig. 8. The electronic brake control unit 12 can extract as a time interval for calculating the turning wheel radius any time interval in which it is determined that the vehicle 10 is turning right or left, regardless of the size of the steering angle of the target wheel.

[0152] The wear determination system 100 according to the above embodiment determines that the vehicle 10 travels straight ahead when the steering angle of the steering wheel is greater than or equal to 0 degrees and less than 90 degrees in the steering angle determination method of Fig. 5. The wear detection system 100 determines that the vehicle 10 turns right or left when the steering angle of the steering wheel is greater than or equal to 90 degrees. The size of the steering angle used as a reference for the determination by the wear detection system 100 is not limited to the embodiment described above.

[0153] As in Fig. As shown in Figure 10, the information transmission device 11, according to the embodiment described above, transmits the information indicating the straight-line wheel radius and the curved wheel radius when both the straight-line wheel radius and the curved wheel radius have been calculated. If only the straight-line wheel radius or only the curved wheel radius has been calculated, the information transmission device 11 can transmit information indicating the calculated value. A configuration can be used in which the wear determination device 25 determines the wear of the shoulder areas 29 when both the straight-line wheel radius and the curved wheel radius are available, even if the information indicating the straight-line wheel radius and the information indicating the curved wheel radius are received by the information transmission device 11 at different times.

[0154] The wear detection device 25 according to the above embodiment determines the wear of both the left and right shoulder areas 29 of the target wheel. The wear detection device 25 can determine the wear of the shoulder areas 29 of the target wheel without distinguishing between the right and left sides.

[0155] The information transmission device 11 according to the above embodiment transmits to the wear determination device 25 the information specifying the straight-line wheel radius and the turning wheel radius as information about the vehicle 10. The information about the vehicle 10 transmitted by the information transmission device 11 is not limited to the above embodiment. For example, the information transmission device 11 can transmit to the wear determination device 25 the information specifying the difference between the straight-line wheel radius and the turning wheel radius.

[0156] In the embodiment described above, the wear detection device 25 determines the wear of the shoulder areas 29 after the information transmission device 11 has calculated the straight-line wheel radius and the curved wheel radius. In the wear detection system 100, the wear detection device 25 can calculate the straight-line wheel radius and the curved wheel radius.

[0157] In this case, the wear determination device 25 obtains values ​​measured by several sensors of the vehicle 10 during the calculation period. The wear determination device 25 executes the procedures initiated by the electronic brake control unit 12, instead of the electronic brake control unit 12. Fig. 5, Fig. 7 and Fig. 8 will be executed.

[0158] It is also conceivable that, when the wear determination device 25 calculates the straight-line wheel radius and the curve-bound wheel radius, the electronic brake control unit 12 uses some of the methods from the Fig. 5, Fig. 7 and Fig. 8 executes and the wear determination device 25 the remaining methods from the Fig. 5, Fig. 7 and Fig. 8 executes.

[0159] For example, the electronic brake control unit 12 can, after the steering angle determination procedure has been carried out, Fig. 5. Information specifying the sensor readings for each subdivided time interval is transmitted to the wear determination device 25. For example, the electronic brake control unit 12 can, after performing the steering angle determination procedure, Fig. 5 and the determination time interval extraction method from Fig. 8. Transfer information specifying values ​​required to calculate the straight-running wheel radius and the curved wheel radius to the wear determination device 25.

[0160] In the aforementioned wear determination system 100, the wear determination device 25 is a server installed outside the vehicle 10. The wear determination device 25 can also be an internal vehicle device. In this case, the information transmission device 11 need not include the communication device 13.

[0161] In the above embodiment, the wear determination system 100 comprises the information transmission device 11, which calculates the straight-line wheel radius and the curved wheel radius, and the wear determination device 25, which determines the wear of the shoulder areas 29. In the wear determination system 100, a device comprising a processing circuit can perform the calculation of the straight-line wheel radius and the curved wheel radius and the determination of the wear of the shoulder areas 29.

[0162] In the embodiment described above, the wear detection system 100 determines the wear of the shoulder areas 29 by comparing the straight-line wheel radius and the curved wheel radius. The wear detection system 100 does not necessarily have to use the straight-line wheel radius to determine the wear of the shoulder areas 29. The wear detection system 100 can determine that the shoulder areas 29 are worn when the curved wheel radius is less than a threshold value. The wear detection system 100 can determine that the shoulder areas 29 are worn when the difference between the curved wheel radius and a predetermined value is greater than or equal to a threshold value. The wear detection system 100 can store the calculated curved wheel radius and determine the wear of the shoulder areas 29 based on a change in the curved wheel radius.

[0163] In the above embodiment, the wear determination device 25 determines the wear of the shoulder areas 29 based on the difference between the straight-line wheel radius and the wheel radius when turning. The wear determination device 25 can determine the wear of the shoulder areas 29 based on the ratio of the wheel radius when turning to the wheel radius when straight.

[0164] Fig. Figure 12 illustrates a communication mode executed by the wear determination device 25 to determine the wear of the shoulder areas 29 of the target wheel in the wear determination system 100 of the first modification. In the first modification, the Fig. 12 communication modes shown instead of the one in Fig. The communication mode shown in section 10 was executed.

[0165] Similar to the mode of Fig. 10 is in Fig. Figure 12 shows a mode in which the electronic brake control unit 12 transmits the information specifying the straight-running wheel radius and the curve-running wheel radius to the communication device 13 and the communication device 13 transmits the information to the wear determination device 25.

[0166] As in the upper part of Fig. As shown in Figure 12, the wear determination device 25 performs the wear determination procedure in the same way as in the upper part of Fig. 10 out.

[0167] In the wear determination procedure, the wear determination device 25 monitors the ratio of the wheel radius when cornering to the wheel radius when traveling straight. The wear determination device 25 monitors a ratio of b2 to b1 when determining the wear of the right shoulder area 29 of the left front wheel 21. The wear determination device 25 monitors a ratio of b3 to b1 when determining the wear of the left shoulder area 29 of the left front wheel 21. The wear determination device 25 monitors a ratio of c2 to c1 when determining the wear of the right shoulder area 29 of the right front wheel 22. The wear determination device 25 monitors a ratio of c3 to c1 when determining the wear of the left shoulder area 29 of the right front wheel 22.

[0168] Since the shoulder areas 29 are worn, the turning wheel radius decreases to such an extent that the ratio of the turning wheel radius to the straight-line wheel radius decreases. As in the lower part of Fig. As shown in Figure 12, the wear determination device 25 determines that the shoulder areas 29 of the target wheel are worn when the ratio of the curve-running wheel radius to the straight-running wheel radius is less than or equal to a threshold value.

[0169] The wear detection device 25 determines that the right shoulder area 29 of the left front wheel 21 is worn when the ratio of b2 to b1 is less than or equal to a threshold value. The wear detection system 100 calculates the straight-line wheel radius, which is the dynamic load radius of the target wheel while the vehicle 10 is traveling straight ahead. The wear detection system 100 determines that the shoulder areas 29 of the target wheel are worn when the ratio of the cornering wheel radius to the straight-line wheel radius is less than or equal to the threshold value.

[0170] As in the lower part of Fig. As shown in Figure 12, after determining the wear of the shoulder areas 29, the wear determination device 25 stores the wheel radius received from the information transmission device 11 in the storage device 27. This method is similar to the method carried out by the wear determination device 25, which is shown in the lower part of Fig. 10 is shown.

[0171] In this case, the wear determination system 100 calculates the straight-line wheel radius, which is the dynamic load radius of the target wheel while the vehicle 10 is traveling straight ahead. The wear determination system 100 determines that the shoulder areas 29 of the target wheel are worn if the ratio of the cornering wheel radius to the straight-line wheel radius is less than or equal to the threshold value.

[0172] Since the shoulder areas 29 of the target wheel are worn, the dynamic load radius present during right or left turns of the vehicle 10 is smaller than the dynamic load radius present during straight-ahead driving of the vehicle 10. The wear detection system 100 monitors the ratio of the turning wheel radius to the straight-ahead wheel radius. This allows the wear detection system 100 to determine the wear of the shoulder areas 29 of the target wheel.

[0173] The examples above can be modified in form and detail without altering the spirit and scope of the claims and their equivalents. The examples serve only for description and not for limitation. Descriptions of features in each example are to be considered applicable to similar features or aspects in other examples. Suitable results can be obtained by performing sequences in a different order and / or by combining components differently in a described system, architecture, device, or circuit and / or by replacing or supplementing them with other components or their equivalents. The scope of disclosure is not defined by the detailed description but by the claims and their equivalents. All variations within the scope of the claims and their equivalents are contained in the disclosure. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2024-069109

[0001] JP 2021-172280

[0003]

Claims

[1] Wear determination system (100) which determines the wear of a target wheel which is a steered wheel on a vehicle (10), wherein the wear determination system (100) is designed, to calculate a ground speed of the target wheel and a rotational speed of the target wheel, wherein the ground speed and the rotational speed are obtained in the same section during a right or left turn of the vehicle (10), to calculate a cornering wheel radius, which is a dynamic load radius of the target wheel during right or left turns of the vehicle (10), based on the ground speed and the rotational speed, and to determine the wear of a shoulder area (29) of the target wheel based on the wheel radius during cornering. [2] Wear determination system (100) according to claim 1, wherein the wear determination system (100) is configured to calculate the ground speed of the target wheel, which is present during the right or left turn of the vehicle (10), based on a yaw rate of the vehicle (10) and a steering angle of the target wheel, which are obtained in the same section during the right or left turn of the vehicle (10), and a wheelbase length of the vehicle (10). [3] Wear determination system (100) according to claim 1 or 2, wherein the wear determination system (100) is configured, to calculate a straight-running wheel radius which is a dynamic load radius of the target wheel during straight-running of the vehicle (10), and to determine the shoulder area (29) of the target wheel as worn if a difference between the turning wheel radius and the straight-line wheel radius is greater than or equal to a threshold value. [4] Wear determination system (100) according to claim 1 or 2, wherein the wear determination system (100) to calculate a straight-running wheel radius which is a dynamic load radius of the target wheel during straight-running of the vehicle (10), and to determine the shoulder area (29) of the target wheel as worn if a ratio of the curve-running wheel radius to the straight-running wheel radius is less than or equal to a threshold value. [5] Wear determination system (100) according to any one of claims 1 to 4, wherein the wear determination system (100) is configured not to calculate the wheel radius when cornering if the steering angle of the target wheel is less than or equal to a predetermined angular reference value. [6] Wear determination system (100) according to any one of claims 1 to 5, wherein the wear determination system (100) is configured not to calculate the wheel radius when cornering if the speed of movement of the vehicle (10) during the right or left turn of the vehicle (10) is greater than or equal to a predetermined speed reference value. [7] Wear determination system (100) according to any one of claims 1 to 6, comprising: a wear determination device (25); and an information transmission device (11), wherein the information transmission device (11) is designed, to calculate the ground speed of the target wheel and the rotational speed of the target wheel in the same section during the right or left turn of the vehicle (10), to calculate the turning wheel radius based on the ground speed and the rotational speed and to transmit the wheel radius running in curves to the wear determination device (25), and the wear determination device (25) is designed to determine the wear of the shoulder area (29) of the target wheel based on the wheel radius when cornering. [8] Wear determination system (100) according to claim 7, wherein the wear determination device (25) has a storage device (27) and is configured to store the wheel radius received from the information transmission device (11) in the storage device (27). [9] Wear determination device (25) which determines the wear of a target wheel which is a steered wheel on a vehicle (10), wherein the wear determination device (25) is designed to determine the wear of a shoulder area (29) of the target wheel based on a turning wheel radius, which is a dynamic load radius of the target wheel during a right or left turn of the vehicle (10), and the turning wheel radius is calculated based on a ground speed of the target wheel and a rotational speed of the target wheel, which are obtained in the same section during the right or left turn of the vehicle (10). [10] Information transmission device (11) configured to communicate with the wear determination device (25) according to claim 9, wherein the information transmission device (11) is designed, to calculate the ground speed of the target wheel and the rotational speed of the target wheel in the same section during the right or left turn of the vehicle (10), and to calculate the turning wheel radius based on the ground speed and the rotational speed, and to transfer the wheel radius as it curves to the wear determination device (25).

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