Wheel arrangement for a vehicle, vehicle with a wheel arrangement and method for controlling a vehicle based on wheel-related data

Abstract

Wheel arrangement (1) for a vehicle (10), wherein the wheel arrangement (1) comprises at least one wheel (2) with a wheel bearing device (4) and with a tire (5), wherein the tire (5) is arranged on the wheel bearing device (4), wherein the at least one wheel (2) comprises several sensor devices (7a, 7b) for recording wheel-related data (D1, D2), wherein at least one of the sensor devices (7a) for recording first wheel-related data (D1) is integrated in the wheel bearing device (1) and that at least one further of the sensor devices (7b) for recording second wheel-related data (D2) is integrated in the tire (5), characterized in that the wheel arrangement (1) comprises a control and evaluation device (3) for evaluating the first wheel-related data (D1) and the second wheel-related data (D2) and for controlling the vehicle (10) on the basis of the evaluated wheel-related data (D3), wherein the first wheel-related data (D1) are dynamic measurement data and the second wheel-related data (D2) are absolute measurement data.

Description

[0001] The invention relates to a wheel assembly for a vehicle, wherein the wheel assembly comprises a wheel with a wheel bearing assembly and a tire. The tire is arranged on the wheel bearing assembly. The wheel includes several sensor devices for acquiring wheel-related data. The invention further relates to a vehicle with a wheel assembly and a method for controlling a vehicle based on wheel-related data.

[0002] For the guidance of vehicles, especially automated vehicles, the forces acting on the tires are determined, e.g., to ascertain the current vehicle position and to control the vehicle's safety systems. It is already known from the prior art to integrate sensors into a wheel bearing of a vehicle's wheel.

[0003] For example, German patent application DE 101 64 929 B4 describes a method for determining reaction forces in a wheel bearing. This method determines the reaction forces that result in the wheel bearing from forces acting on the tire during driving. Sensors are integrated into the wheel bearing for this purpose.

[0004] Furthermore, it is known from the prior art to integrate sensors into a tire of a vehicle wheel. For example, EP 1 691 993 B1 describes a sensor transponder and a method for measuring tire contact patch and wheel load. To calculate the tire contact patch, a sensor transponder with at least one accelerometer is arranged on the inside of a tire tread. Signals from the accelerometer are compared with threshold values ​​and integrated. By calculating a ratio, the tire contact patch is determined independently of speed. The wheel load is calculated from the tire contact patch and the tire pressure.

[0005] The object of the invention is to propose an improved solution for a wheel of a wheel assembly for a vehicle, with which forces and / or moments acting on the wheel can be detected in order to control the vehicle safely and as required.

[0006] This problem is solved by a wheel arrangement for a vehicle with the features of claim 1, by a vehicle with a wheel arrangement with the features of claim 8, and by a method for controlling a vehicle with the features of claim 9. Preferred or advantageous embodiments of the invention will become apparent from the dependent claims, the following description, and the accompanying figures.

[0007] The invention relates to a wheel assembly for a vehicle. The vehicle may be, for example, an automated and / or self-driving vehicle. The vehicle may be a passenger car or a transport and / or heavy-duty vehicle. Preferably, the wheel assembly can be integrated into the vehicle.

[0008] The wheel assembly comprises at least one wheel. Preferably, the at least one wheel is capable of being driven to rotate on a surface, allowing it to roll on the surface. Preferably, several wheels can be integrated into the vehicle to enable the vehicle to be moved along the surface using the wheels.

[0009] The at least one wheel comprises a wheel bearing assembly and a tire. Preferably, the wheel bearing assembly comprises a rotatably driven inner ring and a stationary outer ring. The tire is fixedly arranged on the wheel bearing assembly, particularly on the outer ring, to prevent rotation.

[0010] Optionally, the wheel bearing assembly includes a brake caliper bracket. Optionally, a brake caliper is mounted on the brake caliper bracket to interact with a brake disc or brake pad of the wheel, enabling the rotating wheel to be braked. Preferably, the brake caliper bracket is connected to the outer ring. In particular, the brake caliper bracket projects radially from the outer ring.

[0011] The at least one wheel has several sensor devices designed to acquire wheel-related data. Preferably, the wheel-related data consists of first-order wheel-related data and second-order wheel-related data.

[0012] According to the invention, at least one of the sensor devices is integrated into the wheel bearing assembly so that the first wheel-related data can be acquired. For example, one, two, three or more sensor devices for acquiring the first wheel-related data are integrated into the wheel bearing assembly.

[0013] In addition, the invention provides that at least one further sensor device is integrated into the tire so that the second wheel-related data can be acquired. For example, two, three or more further sensor devices for acquiring the second wheel-related data are integrated into the tire.

[0014] One aspect of the invention is to acquire parameters from the vehicle that allow the vehicle's state and / or position to be determined in real time. Such parameters include, for example, forces acting on the wheel, particularly on the tire and / or the wheel bearing assembly, the tire's coefficient of friction, lateral grip potential, an estimated vehicle load, the vehicle's sideslip angle, etc. Another parameter to be acquired is, for example, odometry, which includes, in particular, vehicle movement and / or vehicle localization. Specifically, the invention aims to improve the determination of odometry by knowing the tire forces and by more accurately estimating slip angles.

[0015] Based on general experience and / or the state of the art, it is known that the sensor devices integrated into the wheel bearing assembly can provide accurate measurement data in dynamic measurement scenarios, i.e., while the vehicle is in motion or during braking. However, it is not possible to determine precise absolute values ​​of the forces and / or moments acting on the tire using the sensor devices integrated into the wheel bearing assembly.

[0016] In contrast, the sensor devices integrated into the tire can accurately determine absolute forces and / or moments acting on the tire, especially when the vehicle is stationary or traveling at low speeds. However, these sensors are less accurate in dynamic measurement scenarios. Therefore, on their own, the sensors integrated into the tire can only provide limited results for determining the vehicle's condition and / or position.

[0017] Within the scope of the invention, it is preferably provided that the absolute forces acting on the tire of the wheel of the wheel arrangement according to the invention can be precisely detected by the at least one further sensor device integrated in the tire. In contrast, the at least one sensor device integrated in the wheel bearing detects, in particular, the forces and / or moments acting on the tire very accurately in dynamic measurement cases. By combining the arrangement of the at least one further sensor device integrated in the tire and the at least one sensor device integrated in the wheel bearing, a highly dynamic and at the same time precise detection of the forces acting on the tire can thus be advantageously carried out. In particular, the absolute forces detected by the at least one further sensor device can form a basis for the calibration of the at least one sensor device integrated in the wheel bearing.

[0018] In a particularly preferred embodiment of the invention, the wheel arrangement comprises a control and evaluation unit. The control and evaluation unit is preferably configured to evaluate the first and second wheel-related data.

[0019] Preferably, the at least one sensor device integrated into the wheel bearing assembly transmits the first recorded wheel-related data to the control and evaluation unit for analysis. In particular, the at least one further sensor device integrated into the tire transmits the second recorded wheel-related data to the control and evaluation unit for analysis. For this purpose, the sensor devices are connected to the control and evaluation unit via signal transmission, e.g., via at least one radio link.

[0020] Within the scope of the invention, it is also possible that the at least one sensor device integrated in the wheel bearing assembly is connected to the at least one sensor device integrated in the tire via a signal connection. For example, the sensor devices in the wheel bearing assembly and the sensor devices in the tire are connected to each other via the at least one radio link. In particular, the acquired first wheel-related data and the acquired second wheel-related data can be fused together and transmitted as fused data to the control and evaluation unit for evaluation.

[0021] In a further preferred embodiment of the invention, the control and evaluation unit is configured to control the vehicle based on the evaluated wheel-related data. For example, the control and evaluation unit can control vehicle assistance systems, such as ABS or ESP, depending on the vehicle's condition and / or position, wherein the vehicle's condition and / or position was determined based on the evaluated first and second wheel-related data.

[0022] In a preferred embodiment of the invention, the control and evaluation unit evaluates the first wheel-related data and the second wheel-related data. Preferably, the control and evaluation unit calibrates the first evaluated wheel-related data based on the second evaluated wheel-related data. In particular, the control and evaluation unit uses the acquired absolute second wheel-related data as the basis for calibrating the first wheel-related data acquired in the dynamic measurement cases. This ensures that the forces and / or moments acting on the wheel can be determined precisely and with high dynamics. This allows for more precise and safer vehicle control.

[0023] Within the scope of the invention, it is provided, for example, that the at least one sensor device integrated into the wheel bearing assembly is arranged on the outer ring of the wheel bearing assembly. Preferably, one, several, or all sensor devices are arranged at regular intervals on the outer circumference of the outer ring. It is also possible within the scope of the invention that one or more sensor devices are arranged on the brake caliper carrier.

[0024] In a preferred embodiment of the invention, the at least one sensor device integrated into the wheel bearing assembly is designed as a strain gauge or a thin-film strain gauge for detecting a change in stress within the wheel bearing assembly. This change in stress is, in particular, a reaction force generated during vehicle operation and / or acting on the wheel bearing assembly. Preferably, the sensor devices arranged on the outer ring are designed to detect the change in stress within the outer ring. Optionally, the sensor devices arranged in the brake caliper carrier detect forces and / or stresses acting in the brake pad carrier when the wheel is braked.

[0025] Preferably, the first wheel-related data are dynamic measurement data. Preferably, the dynamic measurement data can be acquired while the vehicle is driving and / or braking. In particular, the dynamic measurement data are acquired by the at least one sensor device while the vehicle is driving and / or braking.

[0026] For example, the first wheel-related data includes the stress changes in the wheel bearing assembly, particularly in the outer ring and / or the brake pad carrier. Optionally, longitudinal, lateral, and vertical forces and moments acting on the wheel, especially during vehicle travel and / or braking, can be calculated from these stress changes.

[0027] In a preferred embodiment of the invention, two, three, or more additional sensor devices are integrated into the tire. Preferably, the additional sensor devices, in particular some or all of them, are integrated into the tire at regular intervals. Preferably, the additional sensor devices are arranged around the circumference of the tire. It is possible that the additional sensor devices are arranged on the inner surface of a tread of the tire. For example, the additional sensor devices are vulcanized into the tire.

[0028] In a preferred embodiment of the invention, the at least one further sensor device for acquiring the second wheel-related data comprises at least one acceleration sensor. In particular, the at least one acceleration sensor is configured to detect centrifugal acceleration. Specifically, the at least one acceleration sensor detects a time- and angle-dependent centrifugal acceleration to which the at least one acceleration sensor is exposed on the rotating tire. For example, the at least one acceleration sensor is a capacitive, piezoelectric, electrodynamic, ferroelectric, and / or piezoresistive acceleration sensor.

[0029] The at least one additional sensor device can optionally include at least one pressure sensor for acquiring the second wheel-related data. Preferably, the at least one pressure sensor is designed to detect the tire's internal pressure.

[0030] Preferably, the second wheel-related data are absolute measurement data. Preferably, the second wheel-related data are discontinuous, non-dynamic, and can be acquired during stationary maneuvers and / or at low vehicle speeds. In particular, the second wheel-related data can be acquired as the absolute measurement data discontinuously, non-dynamically, during stationary maneuvers and / or at low vehicle speeds by the additional sensor device.

[0031] The second set of wheel-related data includes, in particular, centrifugal acceleration and / or tire inflation pressure. Preferably, a tire contact patch length can be determined from the centrifugal acceleration, relative to and independent of speed. Specifically, a tire contact area can be calculated from the tire contact patch length, the tire inflation pressure, and tire-specific characteristics such as dimensions, construction, and material. The tire contact patch, also called the contact area, forms, in particular, the effective contact area between the tire and the surface on which the vehicle travels. Preferably, the tire contact patch influences the traction behavior, especially the power transmission behavior and the braking behavior of the wheel. The tire contact patch also affects friction losses generated by the rolling process and the associated flexing of the tire.From the tire contact patch and the tire pressure, the tire force and lateral and longitudinal forces of the tire can be determined.

[0032] In one possible embodiment of the invention, the control and evaluation unit determines the wheel contact forces on the ground based on the stress changes detected in the outer ring. Wheel contact forces are, in particular, forces acting between the tire and the ground. These forces include, in particular, longitudinal, lateral, and vertical forces and moments acting on the wheel.

[0033] The wheel contact forces can be altered, and in particular reduced, by the applied braking forces when the wheel decelerates. Preferably, the control and evaluation unit is designed to determine a center of gravity and / or point of application and a magnitude of the braking force. Specifically, the control and evaluation unit calculates the influence of the braking force on the wheel contact forces. In particular, the control and evaluation unit subtracts the braking force from the wheel contact forces. This allows for better and safer control of the vehicle, especially during braking.

[0034] In a preferred embodiment of the invention, the control and evaluation unit is configured to determine the tire contact patch length and / or the tire contact area based on the detected centrifugal acceleration of the tire. In particular, the control and evaluation unit is configured to determine the tire contact area based on the tire contact patch length, the tire inflation pressure, and the tire-specific characteristics.

[0035] In a particularly preferred implementation of the invention, the control and evaluation device calculates the tire force and the lateral and longitudinal forces of the tire based on the tire contact area and the tire internal pressure.

[0036] A further aspect of the invention is a vehicle with a wheel arrangement, in particular with the wheel arrangement according to the foregoing description and / or according to any one of claims 1 to 7. Preferably, the vehicle comprises several wheels of the wheel arrangement. It is preferred that the wheel comprises only one control and evaluation unit of the wheel arrangement for evaluating all wheel-related data acquired in the wheels. Alternatively, the vehicle can also comprise several control and evaluation units for this purpose.

[0037] A method for controlling a vehicle according to the foregoing description and / or according to claim 9 constitutes a further subject matter of the invention. Within the framework of the method, the first wheel-related data and the second wheel-related data are acquired and evaluated. The vehicle is controlled based on the evaluated first and second wheel-related data.

[0038] Further features, advantages, and effects of the invention will become apparent from the following description of preferred embodiments of the invention. These include: Fig. 1 an abstractly represented vehicle with a schematic wheel arrangement, wherein the wheel arrangement comprises a wheel and a control and evaluation device; Fig. 2 the wheel of the wheel assembly in a top view from the side and from above, wherein sensor devices for recording wheel-related data are integrated into the wheel.

[0039] Corresponding or identical parts are each provided with the same reference symbols in the figures.

[0040] In the Fig. Figure 1 shows a highly abstract representation of vehicle 10. Vehicle 10 is designed as an automatically controlled and / or self-driving car or heavy goods vehicle.

[0041] The vehicle 10 comprises a wheel arrangement 1. The wheel arrangement 1 has at least one wheel 2 and a control and evaluation device 3.

[0042] Wheel 2 is in the Fig. Figure 2 shows a plan view from the side and from above. The wheel 2 comprises a wheel bearing assembly 4 and a tire 5, the tire 5 being arranged on the wheel bearing assembly 4. The wheel bearing assembly 4 has an inner ring that can be driven to rotate and a stationary outer ring. The tire 5 is fixedly mounted on the outer ring. The rotating inner ring transmits the rotation to the outer ring and from there to the tire 5, so that the wheel 2 can roll on the surface 6 and the vehicle 10 can be moved.

[0043] Wheel 2 comprises several sensor devices 7a, 7b. Several sensor devices 7a are integrated into the wheel bearing assembly 4, and further sensor devices 7b are integrated into the tire 5. The sensor devices 7a integrated into the wheel bearing assembly 4 acquire first wheel-related data D1, and the sensor devices 7b integrated into the tire 5 acquire second wheel-related data D2. The first and second wheel-related data D1, D2 are transmitted by the sensor devices 7a, 7b to the control and evaluation unit 3 for evaluation. For this purpose, the sensor devices 7a, 7b are connected to the control and evaluation unit 3 via signal transmission, for example, via at least one radio link.

[0044] Alternatively, the sensor devices 7b can be connected to the sensor devices 7a via a signal connection, in particular via a suitable radio link. This allows the first wheel-related data D1 to be fused with the second wheel-related data D2. The fused data can then be transmitted to the control and evaluation unit 3 for evaluation.

[0045] The control and evaluation unit 3 evaluates the first wheel-related data D1 and the second wheel-related data D2, or alternatively the fused data, and controls the vehicle 10, for example assistance systems of the vehicle, such as an automatic braking system (ABS) or an electric stability action program (ESP) of the vehicle 10, on the basis of the evaluated data D3.

[0046] The sensor devices 7a are designed as strain gauges or thin-film strain gauges. They detect changes in stress and / or forces acting on the wheel bearing assembly 4 during the vehicle 10's operation. Some of the sensor devices 7a, for example, three sensor devices 7a, are arranged at regular intervals from one another on the circumference of the outer ring of the wheel bearing assembly 4. There, they detect changes in stress that occur in the outer ring during the vehicle 10's operation. At least one other sensor device 7a can be arranged on a brake pad carrier (not shown) of the wheel bearing assembly 4 to detect braking forces.

[0047] Thus, the first wheel-related data D1 include the stress changes occurring during the journey of the vehicle 10 and / or during braking of the vehicle 10 as reaction forces in the wheel bearing assembly 4.

[0048] The control and evaluation unit 3 determines from the voltage changes, in particular from the reaction forces, which in the Fig. 2 longitudinal forces Fx, lateral forces Fy, vertical forces Fz and / or moments acting on wheel 2 shown.

[0049] The sensor devices 7a, which are integrated into the wheel bearing assembly 4, very accurately record the first wheel-related data D1 in dynamic measurement cases, i.e., during driving or when the moving vehicle 10 is braking. However, they cannot record exact absolute values ​​of forces and / or moments acting on the tire 5.

[0050] The additional sensor devices 7b are integrated into the tire 5. They comprise at least one pressure sensor 8a for detecting the internal tire pressure of the tire 5. The at least one pressure sensor 8a is integrated inside the tire 5. Furthermore, the additional sensor devices 7b comprise at least one capacitive, piezoelectric, electrodynamic, ferroelectric, and / or piezoresitive accelerometer. For example, the additional sensor devices 7b comprise three accelerometers 8b for detecting a time- and angle-dependent centrifugal acceleration acting on the accelerometers when the vehicle 10 travels on the surface 6. The accelerometers 8b are arranged at regular intervals on a tread of the tire 5.Due to the spaced arrangement of the acceleration sensors 8b, the detection of centrifugal acceleration cannot take place continuously and is relatively undynamic, especially at low driving speeds of the vehicle 10.

[0051] Thus, the second wheel-related data D2 includes the centrifugal acceleration and the tire pressure.

[0052] The control and evaluation unit 3 calculates a tire contact patch length of the tire 5 from the centrifugal acceleration, relative to and independent of speed. Taking into account the measured tire pressure and tire-specific characteristics, such as dimensions, construction, and material of the tire 5, the control and evaluation unit calculates a tire contact patch, the so-called contact patch L, based on the tire contact patch length, which is then used in the Fig. Figure 2 shows the contact patch L, an effective contact area of ​​the tire 5 with the surface 6. It influences the traction behavior of the wheel 2 and affects friction losses caused by rolling processes and the associated flexing of the tire 5.

[0053] The control and evaluation unit 3 determines absolute forces from the contact patch L and the tire internal pressure, which are a tire force P and / or longitudinal and lateral forces Δy of the tire 5, which are derived from the Fig. 2 can be found below.

[0054] The sensor devices 7b integrated into the tire 5 can accurately measure the absolute forces acting on the tire 5 in non-dynamic measurement cases, particularly when the vehicle 10 is stationary, during steady-state maneuvers, and / or at low speeds. However, they can only determine forces imprecisely in dynamic measurement cases.

[0055] In summary, the forces and / or moments acting on the tire 5 in dynamic measurement scenarios are precisely recorded as the first wheel-related data D1 by the sensor devices 7a integrated into the wheel bearing assembly 4. The absolute forces acting on the tire 5 in non-dynamic measurement scenarios are precisely recorded as the second wheel-related data D2 by the additional sensor devices 7b integrated into the tire 5. In particular, the combination of sensor devices 7a and 7b allows the absolute forces and the dynamic tire forces to be recorded in real time. Thus, the combination of sensor devices 7a and 7b provides a highly dynamic and precise recording of all forces and / or moments acting on the tire 5, especially in both dynamic and non-dynamic measurement scenarios.

[0056] The control and evaluation unit 3 uses the second wheel-related data D2, in particular the absolute forces in the tire 5, as a basis for the first wheel-related data D1, in particular for the stress changes and / or reaction forces in the wheel bearing assembly 4 recorded in the dynamic measurement cases. The control and evaluation unit 3 thus calibrates the first wheel-related data D1 based on the second wheel-related data D2. This calibration has the advantage that the exact tire forces and the current vehicle position are determined as accurately as possible, and the vehicle 10 can be controlled safely based on the calibrated values. Reference symbol list 1 Wheel arrangement 2 wheel 3 Control and evaluation unit 4 Wheel bearing assembly 5 tires 6 Subsurface 7a Sensor devices 7b further sensor devices 8a Pressure sensor 8b Accelerometers 10 vehicles D1 first cycling-related data D2 second wheel-related data D3 evaluated data Fx longitudinal forces Fy lateral forces Fz Vertical forces L Latsch P Tire force

Claims

[1] Wheel arrangement (1) for a vehicle (10), wherein the wheel arrangement (1) comprises at least one wheel (2) with a wheel bearing device (4) and with a tire (5), wherein the tire (5) is arranged on the wheel bearing device (4), wherein the at least one wheel (2) comprises several sensor devices (7a, 7b) for recording wheel-related data (D1, D2), wherein at least one of the sensor devices (7a) for recording first wheel-related data (D1) is integrated in the wheel bearing device (1) and that at least one further of the sensor devices (7b) for recording second wheel-related data (D2) is integrated in the tire (5), characterized by, that the wheel arrangement (1) comprises a control and evaluation device (3) for evaluating the first wheel-related data (D1) and the second wheel-related data (D2) and for controlling the vehicle (10) on the basis of the evaluated wheel-related data (D3), wherein the first wheel-related data (D1) are dynamic measurement data and the second wheel-related data (D2) are absolute measurement data. [2] Wheel arrangement (1) according to claim 2, characterized by , that the control and evaluation unit (3) calibrates the first wheel-related data (D1) using the second wheel-related data (D2). [3] Wheel arrangement (1) according to one of the preceding claims, characterized by , that the at least one sensor device (7a) for recording the first wheel-related data (D1) comprises at least one strain gauge and / or at least one thin-film strain gauge. [4] Wheel arrangement (1) according to one of the preceding claims, characterized by, that the first wheel-related data (D1) are stress changes in the wheel bearing assembly (4) formed as reaction forces. [5] Wheel arrangement (1) according to one of the preceding claims, characterized by , that at least one further sensor device (7b) for recording the second wheel-related data (D2) includes at least one acceleration sensor (8b) and / or at least one pressure sensor (8a). [6] Wheel arrangement (1) according to one of the preceding claims, characterized by , that the second wheel-related data (D2) include a centrifugal acceleration of the at least one further sensor device (7b) and / or a tire pressure of the tire (5). [7] Wheel arrangement (1) according to any one of claims 5 to 7, characterized byThe control and evaluation unit (3) determines longitudinal, lateral, vertical forces (Fx, Fy, Fz) and / or moments acting on the wheel (2) based on the recorded reaction forces and / or the control and evaluation unit (3) calculates a tire force (P) as well as longitudinal and lateral forces (Fx, Fy) of the tire (5) based on the recorded centrifugal acceleration and the tire internal pressure. [8] Vehicle (10) with the wheel arrangement (1) according to one of the preceding claims. [9] Method for controlling a vehicle (10), wherein at least one wheel (2) of the vehicle (10) comprises several sensor devices (7a, 7b) that acquire wheel-related data (D1, D2), wherein a control and evaluation device (3) acquires and evaluates the first wheel-related data (D1) in the wheel bearing device (4) and the second wheel-related data (D2) in the tire (5), and wherein the vehicle (10) is controlled on the basis of the evaluated wheel-related first and second data (D3), wherein the first wheel-related data (D1) are acquired as dynamic measurement data and the second wheel-related data (D2) are acquired as absolute measurement data.

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