Method of damping a vehicle

Abstract

A computer-implemented method for damping a vehicle, comprising: receiving external load data of the vehicle (S10); receiving at least one damper speed of a damper of the vehicle (S20); providing an optimization model configured to describe a relationship between the external load data of the vehicle, the at least one damper speed of the damper of the vehicle, and at least one damper force of the at least one damper (S30); determining the at least one damper force of the damper of the vehicle by inputting the external load data and the at least one damper speed into the optimization model (S40); providing the at least one damper force of the at least one damper of the vehicle (S50).

Description

Technical Field

[0001] This disclosure relates to a method for damping a vehicle, an apparatus, system, and computer program elements for damping a vehicle. Background Technology

[0002] Damping systems for vehicles are known in the prior art. A damping system may include one or more of the following: passive dampers, active dampers, or semi-active dampers. Semi-active dampers use a semi-active suspension to separately adjust the damping behavior and the damper force of the damper. This type of damping system aims to improve the vehicle's ride and handling.

[0003] Therefore, it is found that there is a further need to provide an improved method for damped vehicles. Summary of the Invention

[0004] The problem is at least partially resolved or mitigated by the subject matter of the independent claims of this disclosure, wherein further examples are incorporated in the dependent claims.

[0005] According to a first aspect of the invention, a computer-implemented method for a damped vehicle is provided, comprising: receiving external load data of the vehicle; receiving at least one damper speed of a damper of the vehicle; providing an optimization model configured to describe / represent the relationship between the external load data of the vehicle, the at least one damper speed of the vehicle's damper, and at least one damper force of the at least one damper; determining at least one damper force of the vehicle's damper by inputting the external load data and the at least one damper speed into the optimization model; and providing at least one damper force of the at least one damper of the vehicle. The term "damping" as used herein should be understood broadly and particularly refers to the resistance to motion, e.g., the reduction of instability (oscillations, vibrations, etc.) in a device. The term "vehicle" as used herein should be understood broadly and refers to any vehicle. A vehicle can be an automobile, a commercial vehicle. A vehicle can have an electric motor, an internal combustion engine, or a hybrid motor. The term "external load data" as used herein should be understood broadly and particularly refers to the load acting on the vehicle. External load data may include one or more torques and one or more forces. External load data may be caused by road unevenness, road incline, or vehicle acceleration. External load data may relate to the vehicle's load request (e.g., a top-hook load request from a controller performing feedback control for a damped vehicle). The vehicle's load request may be designed to balance one or more torques and one or more forces acting on the vehicle. External load equals external load data. The term "damper speed" as used herein should be understood broadly and refers to the speed of a damper or at least a portion of a damper. Damper speed can be used in conjunction with a damper parameter set to determine, respectively, the calculated damper force and / or the calculated damper torque. The damper parameter set may include one or more damper constants and / or one or more damper curves and / or equations. The damper parameter set may describe the damper behavior of the damper and / or the damping level of the damper. Damper speed can be measured at at least one damper. The term "damper force" as used herein should be understood broadly and refers particularly to the damper force of a damper. The damper force can be further described by the product of the damper parameter set of the damper and the damper velocity of the damper. The determined damper force for at least one damper can be used to adjust at least one damper and at least one damper parameter set, respectively. As used herein, the term "optimization model" should be understood broadly and refers to a model configured to describe / represent the relationship between at least one damper force, at least one damper velocity, and external load data of a damper. The optimization model may include a damper model comprising one or more dampers (e.g., four dampers, one at each wheel of a vehicle).The optimization model can calculate the arbitration and distribution of one or more damper forces (e.g., four damper forces for four dampers, one damper force for each wheel of a car) to balance external load data. Therefore, the optimization model can be configured to obtain geometric data (e.g., the location of at least one damper, the location of the theoretical load application point, etc.). The optimization model may include one or more equations describing the behavior of at least one damper (e.g., linear behavior, nonlinear behavior, linearized behavior). The optimization model includes a nonlinear solver for solving one or more equations. The determined damper force can be provided to a controller configured to adjust the damper parameter sets of at least one damper and at least one damper separately to generate at least one damper force in combination with the velocity of at least one damper. The damper force thus generated can then balance the applied external load corresponding to the load request.

[0006] In other words, this disclosure is based on the finding that by controlling each vertical force (i.e., damper force) at each corner of the vehicle, it is possible to separately control the vehicle and the vehicle body to improve ride comfort or handling. The most important control variables are the modal out-of-plane forces and moments, namely heave force, roll torque, and pitch torque (i.e., external load data). Current semi-active suspension systems typically determine reference values ​​for these modal forces and torques based on the current body motion of the vehicle. The body modal force and moment requests are then distributed to the corners of the vehicle through some simple geometric relationships, generally assuming that the vertical force actuators can transmit forces in any direction, i.e., assuming that the requested forces can be achieved. Furthermore, all methods involve some trade-offs in which body modal force or torque requests are prioritized. This disclosure provides a method for distributing and arbitrating body modal force and torque requests (i.e., external load data) to different corner actuators (i.e., one or more dampers) while taking into account actuator limitations (i.e., force ratio and maximum damper force, respectively). It can also address how to adjust the weighting factors (i.e., parts of the optimization model and cost function, respectively) in an optimization problem using simulation and different road types. This can lead to more precise vehicle damping. This method can be part of feedback control for damping vehicles (e.g., over-the-horse feedback control). The method can focus on distributing one or more damper forces (e.g., four damper forces) to the four corners of the vehicle. This method can obtain these external load data from any controller (e.g., an over-the-horse controller) requesting heave, pitch torque, and / or roll torque (i.e., external load data) and can distribute them to each damper. This can be achieved by adjusting the damper forces. The method can include a cost function that minimizes the error between the requested main control / torque (i.e., external load data) and the actual main control force / torque (i.e., internal counter load data and at least one damper force, e.g., four damper forces, respectively).

[0007] In one implementation, external load data may include the vehicle's heave force, pitch torque, and / or roll torque.

[0008] In one implementation, the damper velocity can be derived from measurements taken by a horizontal sensor located at at least one damper in the vehicle. The damper velocity can be determined and derived separately by forming the horizontal derivative of the damper with respect to time. This can be a precise and efficient method for determining the damper velocity.

[0009] In one implementation, determining at least one damper force may include calculating the vehicle's internal counterload, derived from at least one damper force and / or geometric data of the vehicle, and external load data of the vehicle. The term "internal counterload" should be understood broadly, and particularly refers to a load configured to balance the external load data. The internal counterload includes at least one damper force (e.g., four damper forces, one at each damper of the vehicle) and the corresponding geometric data of the vehicle. The term "geometric data" should be understood broadly, and refers to the spatial location of one or more dampers and one or more points of application of the external load data. In the present context, the internal counterload means the current load provided by at least one damper, taking the geometric data into account. The internal counterload may include one or more forces and one or more torques. The internal counterload may include heave force, roll torque, and / or pitch torque. The internal counterload is equal to the internal counterload data.

[0010] In one implementation, determining at least one damper force of at least one damper of a vehicle may include calculating the minimum and maximum available damper forces of at least one damper. This can lead to a more accurate way of damping the vehicle.

[0011] In one implementation, determining at least one damper force of at least one damper of a vehicle may include calculating at least one force ratio of at least one damper force to at least one maximum available damper force of at least one damper.

[0012] In one implementation, determining at least one damper force of at least one damper of the vehicle may include minimizing a cost function that includes external load, internal load, and / or force ratio. This can improve the efficiency of the damped vehicle because the error between external load data (i.e., load request) and internal counter-load data (i.e., current load) is eliminated or mitigated. Errors may arise because the damper's limitations (e.g., the maximum available damper force is lower than the requested damper force) prevent the provision of an accurate damping force. Errors may also occur because sometimes there is no ideal solution for the internal counter-load to balance the external load (e.g., due to conflicting objectives between heave, pitch torque, roll torque, and force ratio).

[0013] In one implementation, the cost function may include at least one weighting factor, which may be determined by optimization simulation. By considering heave force, roll torque, pitch torque, and force ratio, the weighting factor can help prioritize the determination of the four damper forces. This can increase the accuracy of the method used for damping a vehicle. The weighting factor can be determined continuously via optimization simulation during vehicle operation or offline before vehicle operation. The optimization simulation may include a weighting factor for each term of the cost function. Term in the cost function may include error terms, such as the difference between external load data and internal data (e.g., error terms for heave force, roll torque, and pitch torque). The cost function may also include a force ratio term. Each term can be weighted using a weighting factor. For each single external load data point, multiple possible combinations of weighting factors are possible. To obtain the optimal combination of weighting factors, the optimization simulation may, for example, calculate the minimum value (e.g., the optimal result) of the cost function for each possible combination of weighting factors and select the optimal combination of weighting factors that yields the best result. This can lead to more accurate damping of the vehicle.

[0014] The optimized simulation might look like this: for example, four terms and weighting factors might be penalized, one for heave force, one for pitch torque, one for roll torque, and one each for high-damping current and damper force (Freq / Fmax; i.e., force ratio). The penalty for high current might bias the solution towards lower current values, potentially improving secondary driving but slightly hindering primary driving control. Therefore, the force ratio term can be used to balance primary and secondary driving on different road types.

[0015] The optimization simulation can be performed as follows: Initially, a range of weighting factors can be provided, which determines the total number of different combinations. Simulations can be performed for each weighting factor combination, and the difference (error) between the controller request based on the subject's motion (i.e., external load data) and the damper force at each corner determined using the optimization model (i.e., internal anti-load data) can be stored. For discrete road disturbances (representing only low-frequency primary driving), the error amplitude (from the time-pair error data) can be considered within a precise discrete time window for each individual disturbance. For roads that may contain both high-frequency and low-frequency disturbances (e.g., recorded real roads and rural roads), the average frequency-amplitude spectrum of the error can be calculated over the entire time period (via FFT), with some overlap. For discrete road disturbances, the RMS of the error amplitude can be calculated from the data stored in the previous step for each combination. For roads containing both high-frequency and low-frequency disturbances, the average frequency-amplitude spectrum can be divided into four regions. The RMS amplitude for each region can then be calculated for each error and stored in a multidimensional array. Based on the initial baseline simulation / measurement, the corresponding RMS value for each region in each error can be used to normalize the corresponding RMS amplitude calculated in the previous step. The normalized RMS error value can be scaled around 1. Values ​​below 1 indicate that these results (for certain weight combinations) may be below the benchmark. If the value may be greater than 1, it indicates that the response of the corresponding weighted factor combination may be above the benchmark. The RMS error of all simulated weighted factor combinations can be normalized using the corresponding benchmark RMS error value. Adjustment limits can be factors that are set and used to control the level of improvement in the (filtered) response. It can simply represent the minimum normalized RMS value allowed in each error. For example, a value of 1.02 represents 102% of the response (i.e., the response may exceed the benchmark by 2%, and weighted factor combinations with responses greater than 2% (relative to the benchmark) are ignored). Adjustment limit values ​​may help define conditions that allow options to focus globally on all errors across all regions, or on certain errors in certain regions. Each normalized error can be compared to its corresponding adjustment limit. In the next step, the unique weighted factor combination that satisfies the above conditions across all regions of the spectrum (0 to 50 Hz) and all forms of error can finally be obtained. In discrete road interference scenarios, a unique combination of weighting factors can eventually be obtained that satisfies the conditions for all individual interference locations and all forms of error. Once some combination of weighting factors satisfying all conditions is available, the next step may be to calculate the cumulative normalized RMS error value. Heave, pitch, and roll RMS error values ​​can be summed individually in each frequency region (primary, intermittent, jitter, and harsh). However, in discrete road interference scenarios, the heave, pitch, and roll RMS error values ​​can be summed within each discrete interference time window.The total error can then be calculated by summing the errors of all regions or all individual discrete disturbance time windows. The total error allows for a global consideration of all errors across all regions. Conversely, individual region errors can be considered in a further process, which can help focus only on the region of interest. The total errors can then be compared with each other and also with a baseline error (which is always one for a given error, since three different errors in four regions can be considered, resulting in a total baseline error of 12). The minimum total error and the corresponding weighting factor value represent the optimal solution. The optimal weighting factor can provide the best solution based on the defined conditions.

[0016] In one implementation, determining at least one damper force of at least one damper of a vehicle may include calculating the minimum and maximum current of at least one damper. For example, for each of the four dampers of the vehicle, the minimum and maximum currents can be determined separately. This can improve the accuracy of the method used for damping the vehicle. Given the current constraints of the preview time and the current damper speed, the maximum and minimum damper forces can be calculated and used as inputs to the method. Furthermore, the current damper speed can be measured and used as input for calculating the maximum and minimum damper forces. Future predicted damper speeds can also be included in the optimization model.

[0017] In one implementation, the external load can be derived from at least one acceleration sensor located in the vehicle. The acceleration sensor can allow the position data of the acceleration sensor to be combined to calculate heave, roll torque, and / or pitch torque.

[0018] In one implementation, at least one damper is a semi-active damper. The semi-active damper may include a semi-active suspension for separately controlling and adjusting the damper parameter set of the damper. The damper parameter set can be adjusted by separately applying voltage and current to the semi-active suspension. This could be useful for actively controlling damping systems in vehicles.

[0019] In one implementation, the vehicle may have four dampers arranged at the respective four wheels of the vehicle.

[0020] On the other hand, an apparatus for a damped vehicle is disclosed, comprising: a first receiving unit configured to receive external load data of the vehicle; a second receiving unit configured to receive at least one damper speed of a damper of the vehicle; a first providing unit configured to provide an optimization model, the optimization model being configured to describe the relationship between a target load of the vehicle, at least one damper speed of the vehicle's damper, and at least one damper force of the at least one damper; a determining unit configured to determine at least one damper force of the vehicle's damper by inputting the external load data and the at least one damper speed into the optimization model; and a second providing unit configured to provide at least one damper force of the at least one damper of the vehicle.

[0021] On the other hand, it relates to a system comprising: a device for damping a vehicle as described above; and a vehicle.

[0022] The final aspect relates to a computer program element configured, when executed by a processor, to perform the methods described above, and / or control the devices described above, and / or control the systems described above. Attached Figure Description

[0023] The present disclosure will be described exemplarily below with reference to the accompanying drawings, wherein:

[0024] Figure 1 This is a schematic diagram of a method for damping a vehicle according to an example of the present invention; and

[0025] Figure 2 This is a schematic diagram of a device for a damped vehicle according to an example of the present invention.

[0026] It should be noted that the accompanying drawings are merely schematic diagrams and are intended to illustrate examples of this disclosure only. In principle, identical or equivalent elements have the same reference numerals. Detailed Implementation

[0027] Figure 1 A schematic diagram of a method for damping a vehicle according to an example of the present invention is shown.

[0028] In the first step S10, external load data of the vehicle is received. This external load data can be transmitted from a controller (e.g., a feedback controller for hook feedback control). The external load data may include heave force, pitch torque, and roll torque. Optionally or additionally, the external load data can be derived from measurements taken by acceleration sensors located in the vehicle.

[0029] Step S20 includes receiving at least one damper velocity of at least one damper of the vehicle. The damper velocity can be derived from measurements by a horizontal sensor disposed at at least one damper of the vehicle. The damper may be a semi-active damper. In this example, four dampers in the vehicle are considered. In this example, the dampers are disposed at the wheels of the vehicle and at the corners of the vehicle.

[0030] Step S30 provides an optimization model configured to describe the relationship between the vehicle's external load data, the speed of at least one damper of the vehicle's dampers, and the damper force of at least one damper of at least one damper.

[0031] Step S40 includes determining at least one damper force of the vehicle's dampers by inputting external load data and at least one damper speed into an optimization model. Determining at least one damper force may include calculating the vehicle's internal counterload. The internal counterload may be derived from the vehicle's at least one damper force and / or geometric data, as well as the vehicle's external load data. Determining at least one damper force of the vehicle's at least one damper may include calculating the minimum and maximum available damper forces of the at least one damper. Determining at least one damper force of the vehicle's at least one damper may include calculating at least one force ratio of the at least one damper force to the maximum available damper force of the at least one damper. Determining at least one damper force of the vehicle's at least one damper may include minimizing a cost function that includes external load, internal load, and / or force ratio. The cost function may include at least one weighting factor, and the at least one weighting factor may be determined through optimization simulation. Determining at least one damper force of the vehicle's at least one damper may include calculating the minimum and maximum currents of the at least one damper.

[0032] Step S50 includes providing at least one damper force to at least one damper of the vehicle. The determined at least one damper force can be provided to a controller configured to adjust the current of the at least one damper based on the information of the damper force.

[0033] Figure 2A schematic diagram of a device 100 for a damped vehicle (not shown) is shown. The device 100 includes: a first receiving unit 110 configured to receive external load data of the vehicle; a second receiving unit 120 configured to receive at least one damper speed of a damper (not shown) of the vehicle; a first providing unit 130 configured to provide an optimization model described as relating a target load of the vehicle, at least one damper speed of the vehicle's dampers, and at least one damper force of the at least one damper; a determining unit 140 configured to determine at least one damper force of the vehicle's dampers by inputting the external load data and the at least one damper speed into the optimization model; and a second providing unit 150 configured to provide at least one damper force of the at least one damper of the vehicle. The first receiving unit 110, the second receiving unit 120, the first providing unit 130, the determining unit 140, and the second providing unit 150 may also be implemented in a single hardware unit and / or software unit (e.g., in some aspects of this disclosure, a single unit or control circuit may perform the corresponding steps). The units and / or devices according to one or more examples can be implemented using hardware, software, and / or a combination thereof. For example, the hardware device can be implemented using processing circuitry such as (but not limited to): a processor, central processing unit (CPU), controller, arithmetic logic unit (ALU), digital signal processor, microcomputer, field-programmable gate array (FPGA), system-on-a-chip (SoC), programmable logic unit, microprocessor, or any other device capable of responding to and executing instructions in a defined manner. The unit or device may include one or more interface circuits. The functionality of any given unit of this disclosure can be distributed across multiple units connected via interface circuitry. For example, multiple units can allow for load balancing.

[0034] Those skilled in the art, when practicing the claimed subject matter, can understand and implement other variations of the disclosed examples through study of the drawings, disclosure, and appended claims. Specifically, the various parts / functions of the aforementioned examples can also be combined with each other. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude multiple. The fact that certain measures are enumerated in mutually different dependent claims does not indicate that combinations of these measures cannot be used advantageously. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0035] List of reference numerals

[0036] S10 receives external load data

[0037] S20 Receiver Damper Speed

[0038] S30 provides an optimized model

[0039] S40 determines the damper force.

[0040] S50 provides damping force

[0041] 100 devices

[0042] 110 First Receiving Unit

[0043] 120 Second Receiving Unit

[0044] 130 First Supply Unit

[0045] 140 measurement units

[0046] 150 Second Supply Unit

Claims

1. A computer-implemented method for a damped vehicle, comprising: Receive external load data of the vehicle (S10), wherein the external load data relates to the vehicle's load request; Receive at least one damper speed of the vehicle's damper (S20). An optimization model is provided, which is configured to describe the relationship between external load data relating to a load request of a vehicle, at least one damper speed of the vehicle's damper, and at least one damper force of the at least one damper (S30). Determining at least one damper force of the vehicle's dampers by inputting the external load data and the speed of the at least one damper into the optimization model (S40) includes: calculating at least one force ratio of the at least one damper force to the maximum available damper force of the at least one damper, wherein the optimization model calculates the distribution of one or more damper forces in consideration of the maximum available damper force in order to balance the external load data; Provide at least one damper force (S50) to at least one damper of the vehicle.

2. The method according to claim 1, wherein the external load data includes the vehicle's heave force, the vehicle's pitch torque, and / or the vehicle's roll torque.

3. The method according to claim 1 or 2, wherein the damper speed is derived from measurements taken by a horizontal sensor disposed at at least one damper of the vehicle.

4. The method according to claim 1 or 2, wherein determining the at least one damper force comprises calculating the internal counterload of the vehicle, the counterload being derived from at least one damper force and / or geometric data of the vehicle and external load data of the vehicle.

5. The method according to claim 1 or 2, determining at least one damper force of at least one damper of the vehicle includes calculating the minimum and maximum available damper forces of the at least one damper.

6. The method of claim 1, wherein determining at least one damper force of at least one damper of the vehicle comprises minimizing a cost function, said cost function comprising the external load, internal load and / or the force ratio.

7. The method of claim 6, wherein the cost function includes at least one weighting factor, and the at least one weighting factor is determined by optimization simulation.

8. The method according to claim 1 or 2, determining at least one damper force of at least one damper of the vehicle includes calculating the minimum current and maximum current of the at least one damper.

9. The method according to claim 1 or 2, wherein the external load is derived from at least one acceleration sensor arranged in the vehicle.

10. The method according to claim 1 or 2, wherein the at least one damper is a semi-active damper.

11. The method according to claim 1 or 2, wherein the vehicle has four dampers arranged at each of the four respective wheels of the vehicle.

12. A device (100) for damping a vehicle, comprising: The first receiving unit (110) is configured to receive external load data of the vehicle, wherein the external load data relates to a load request of the vehicle; The second receiving unit (120) is configured to receive at least one damper speed of the vehicle's damper; The first providing unit (130) is configured to provide an optimization model, which is configured to describe the relationship between the target load of the vehicle, the speed of at least one damper of the vehicle's damper, and the damper force of at least one damper of the at least one damper. The determining unit (140) is configured to determine at least one damper force of the vehicle's dampers by inputting the external load data and the at least one damper speed into the optimization model, including: calculating at least one force ratio of the at least one damper force to the maximum available damper force of the at least one damper, wherein the optimization model calculates the distribution of one or more damper forces in consideration of the maximum available damper force in order to balance the external load data; The second supply unit (150) is configured to provide at least one damping force to at least one damper of at least one damper of the vehicle.

13. A system comprising: The device for damping vehicles according to claim 12; as well as vehicle.

14. A computer program element, which, when executed by a processor, is configured to perform the method according to any one of claims 1 to 11, and / or control the device according to claim 12, and / or control the system according to claim 13.

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