A road road spectrum in-loop test method, device, electronic equipment and storage medium

Abstract

The application provides a road profile in-loop test method, device, electronic equipment and storage medium, and relates to the technical field of vehicles.The road profile in-loop test method comprises the following steps: determining a road excitation compensation amount according to a vehicle operating state, wherein the vehicle operating state comprises a tire force state and a tire slip state, and the road excitation compensation amount comprises a first compensation amount generated by tire vertical deformation and a second compensation amount generated by tire slip; determining a total compensation amount according to the first compensation amount, the second compensation amount and a road surface adhesion coefficient; determining an additional correction term through feedback control between an actual vertical force and an estimated vertical force, and generating an excitation displacement instruction according to an original road surface vertical displacement, the total compensation amount and the additional correction term.The application can improve road reproduction accuracy, reduce the deviation between vehicle suspension motion response and real road working conditions, and reduce the risk of passing the bench verification but failing the real vehicle verification.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, and more specifically, to a road spectrum loop test method, apparatus, electronic device, and storage medium. Background Technology

[0002] With the development of vehicle chassis electronic control technology and intelligent driving technology, road reproduction testing based on test benches has become an important means of developing and verifying vehicle chassis dynamics control systems. Among them, Road-in-the-Loop (RiL) testing technology collects road surface roughness information from actual roads in advance, and uses the corresponding road spectrum signal as an excitation input to a hydraulic vibrator, a six-degree-of-freedom road simulation bench, or a rotating hub system. This allows the vehicle or suspension system under test to reproduce real road conditions in a laboratory environment, thereby enabling performance testing of the suspension system, shock absorbers, tires, and related chassis control systems.

[0003] However, current RiL testing systems typically employ an open-loop road spectrum driving approach, directly using the acquired vertical displacement signal of the road as the target displacement input of the exciter. The actuator then reproduces the road surface undulations. This approach assumes a unidirectional transmission relationship between the road input and the vehicle response, meaning that the displacement output by the exciter is equivalent to the actual road excitation experienced by the vehicle. It fails to consider the actual tire contact coupling between the vehicle and the road surface. Consequently, amplitude errors, phase lags, and frequency response distortions inevitably arise between the actual road displacement output by the test bench and the effective road input experienced by the tire contact point during actual vehicle operation. These errors are particularly pronounced under conditions of large load changes, braking, driving, steering, and complex combinations, directly impacting the accuracy of road reproduction. Summary of the Invention

[0004] The problem addressed by this invention is how to improve the accuracy of road reconstruction.

[0005] To address the aforementioned problems, this invention provides a method, apparatus, electronic device, and storage medium for road spectrum loop testing.

[0006] In a first aspect, the present invention provides a method for road spectrum loop-in-the-loop testing, comprising: The road excitation compensation amount is determined based on the vehicle's operating state, which includes the tire's force state and tire slippage state. The road excitation compensation amount includes a first compensation amount generated by the tire's vertical deformation and a second compensation amount generated by the tire slippage. The total compensation amount is determined based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient; Feedback control is used to determine additional correction terms based on the error between the actual vertical force and the estimated vertical force. Excitation displacement commands are generated based on the original road surface vertical displacement, the total compensation amount, and the additional correction terms.

[0007] Optionally, the tire force state includes the wheel vertical force, the tire slip state includes the longitudinal slip ratio and the lateral slip angle, and the determination of the road excitation compensation amount based on the vehicle operating state includes: The first compensation amount is determined based on the wheel vertical force and the tire vertical stiffness; The second compensation amount is determined based on the longitudinal slip ratio, the lateral slip angle, and the slip coupling coefficient.

[0008] Optionally, determining the total compensation amount based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient includes: Determine a first adjustment factor corresponding to the first compensation amount and a second adjustment factor corresponding to the second compensation amount based on the road surface adhesion coefficient; The vertical force compensation amount is determined based on the first compensation amount and the first adjustment factor, the slip compensation amount is determined based on the second compensation amount and the second adjustment factor, and the total compensation amount is determined based on the vertical force compensation amount and the slip compensation amount.

[0009] Optionally, the first adjustment factor is positively correlated with the road surface adhesion coefficient, and the second adjustment factor is negatively correlated with the road surface adhesion coefficient.

[0010] Optionally, the step of determining the additional correction term based on the feedback control of the error between the actual vertical force and the estimated vertical force includes: The vertical force error is determined based on the actual vertical force and the estimated vertical force. The vertical force error is input into the proportional-integral controller to determine the additional correction term.

[0011] Optionally, generating the excitation displacement command based on the original road surface vertical displacement, the total compensation amount, and the additional correction term includes: The original vertical displacement of the road surface is compensated based on the total compensation amount to obtain the compensated road surface displacement; The excitation displacement command is generated based on the compensated road surface displacement and the additional correction term.

[0012] Optionally, the road spectrum in-loop testing method further includes: inputting the excitation displacement command into a road simulation controller to drive the vehicle to reproduce the road spectrum.

[0013] Secondly, the present invention provides a road spectrum in-loop testing device, comprising: The first module is used to determine the road excitation compensation amount based on the vehicle operating state, which includes the tire force state and the tire slip state. The road excitation compensation amount includes a first compensation amount generated by the vertical deformation of the tire and a second compensation amount generated by the tire slip. The second module is used to determine the total compensation amount based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient. The third module is used to determine additional correction terms based on feedback control according to the error between the actual vertical force and the estimated vertical force, and to generate excitation displacement commands based on the original road surface vertical displacement, the total compensation amount and the additional correction terms.

[0014] Thirdly, the present invention provides an electronic device, including a memory and a processor; The memory is used to store computer programs; The processor is configured to implement the road spectrum loop-in-the-loop testing method as described in the first aspect when executing the computer program.

[0015] Fourthly, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the road spectrum loop-in-the-loop testing method as described in the first aspect.

[0016] The beneficial effects of the road spectrum-in-the-loop testing method of the present invention are as follows: the road excitation compensation amount is determined according to the vehicle operating state, and different compensation amounts are adaptively fused in combination with the road surface adhesion coefficient. At the same time, the error between the actual vertical force and the estimated vertical force is used for feedback control to generate additional correction terms, and finally, the excitation displacement command is generated. This establishes a two-way closed-loop coupling relationship between road excitation and vehicle dynamic response, enabling road excitation to adapt to the contact characteristics between the tire and the road surface under different adhesion conditions. This not only improves the accuracy of road reproduction and reduces the deviation between the vehicle suspension motion response and the actual road conditions, but also improves the reliability of bench verification of different chassis control algorithms and reduces the risk of bench verification passing but real vehicle verification failing. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of the road spectrum loop-in-the-loop testing method according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the process for determining the road incentive compensation amount according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the process for determining the total compensation amount according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the process for determining additional correction items according to an embodiment of the present invention; Figure 5This is a schematic diagram of the process for generating excitation displacement commands according to an embodiment of the present invention; Figure 6 This is a schematic diagram illustrating the principle of the road spectrum loop-in-the-loop testing method according to an embodiment of the present invention; Figure 7 This is a system architecture diagram of the road spectrum in-loop testing device according to an embodiment of the present invention; Figure 8 This is a system architecture diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0018] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Although some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the accompanying drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0019] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0020] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to"; the term "based on" means "at least partially based on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; and the term "optionally" means "optional embodiments". Definitions of other terms will be given in the following description. It should be noted that the concepts of "first," "second," etc., mentioned in this invention are used only to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies.

[0021] It should be noted that the terms "a" and "a plurality of" used in this invention are illustrative rather than restrictive. Those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0022] The names of the messages or information exchanged between the multiple devices in the embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of these messages or information.

[0023] like Figure 1As shown, an embodiment of the present invention provides a road spectrum loop-in-the-loop testing method, comprising: S100: Determine the road excitation compensation amount based on the vehicle operating state, which includes the tire force state and the tire slip state, and the road excitation compensation amount includes a first compensation amount generated by the vertical deformation of the tire and a second compensation amount generated by the tire slip.

[0024] Specifically, the vehicle's operating status is collected in real time, including tire force and tire slip states. Tire force primarily reflects changes in the vertical contact load between the wheel and the road surface, and can be obtained from wheel hub force sensors, suspension force sensors, or estimated based on a vehicle dynamics model. Tire slip reflects the relative motion between the tire and the road surface, and can be obtained through a combination of wheel speed sensors, vehicle speed sensors, steering wheel angle sensors, inertial navigation units, and a vehicle state estimator. Because tires do not rigidly contact the road surface during actual vehicle operation but possess a certain degree of elastic deformation capability, the actual contact point of the tire relative to the original road surface geometry changes when the vehicle is subjected to different vertical loads. Furthermore, during braking, driving, or steering, the tire also experiences longitudinal and lateral slippage, causing shear deformation in the tire contact area, further altering the actual road excitation received by the vehicle. Therefore, this… The embodiment no longer directly uses the original road spectrum as the excitation input. Instead, it calculates the road excitation compensation amount based on the current operating state of the vehicle. For example, it calculates the first compensation amount caused by the vertical deformation of the tire based on the tire stress state. The first compensation amount is used to reflect the change in road input caused by the elastic compression of the tire under vertical load. When the vertical load of the wheel increases, the tire compression increases, and the equivalent road height actually contacted by the vehicle decreases. Therefore, it is necessary to compensate for the original road excitation. For example, it calculates the second compensation amount caused by tire slip based on the tire slip state. The second compensation amount is used to reflect the change in equivalent road input caused by factors such as tire contact area deformation, rubber shear effect, and snow-pushing effect caused by longitudinal and lateral slip of the tire. When the vehicle is in driving, braking, or steering conditions, the second compensation amount can reflect the degree of influence of tire slip on road excitation, thereby improving the consistency between the road simulation results and the actual road driving state.

[0025] S200: Determine the total compensation amount based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient.

[0026] Specifically, since different types of road surfaces have different effects on tire contact characteristics, the same tire stress and slippage state will have different degrees of impact on road excitation under different adhesion conditions. For example, on dry asphalt pavement, the tire-road adhesion is high, tire slippage is small, and the vertical deformation of the tire has a more significant impact on road input. On icy or wet pavement, the tire is more prone to slippage, and the impact of tire slippage on road input is more prominent. Therefore, this embodiment further introduces the road adhesion coefficient as an adjustment parameter to adaptively adjust the first compensation amount and the second compensation amount. The first adjustment factor and the second adjustment factor are determined according to the real-time acquired or estimated road adhesion coefficient. The first adjustment factor is used to adjust the contribution ratio of the first compensation amount in the total compensation amount, and the second adjustment factor is used to adjust the contribution ratio of the second compensation amount in the total compensation amount. As the road adhesion coefficient changes, the two adjustment factors change dynamically, thereby realizing the adaptive adjustment of the road excitation compensation strategy under different road conditions. Then, the first compensation amount is weighted using the first adjustment factor to obtain the vertical force compensation amount, and the second compensation amount is weighted using the second adjustment factor to obtain the slip compensation amount. Subsequently, the vertical force compensation amount and the slip compensation amount are fused and calculated to obtain the total compensation amount. In this way, the road excitation compensation amount can automatically adjust the weight of each compensation item according to different road attachment conditions, improve the road reproduction accuracy, and enhance the adaptability of the method to different road environments.

[0027] S300: Based on the error between the actual vertical force and the estimated vertical force, feedback control is used to determine the additional correction term, and an excitation displacement command is generated based on the original road surface vertical displacement, the total compensation amount, and the additional correction term.

[0028] Specifically, after calculating the total compensation, a force feedback closed-loop control is further established. For example, the theoretical vertical force of the wheel can be estimated based on the current excitation displacement and the tire model, and compared with the actual vertical force collected in real time by the vehicle state acquisition module to obtain the vertical force error between the two. Since the tire model is usually established using a simplified model, while the actual vehicle is affected by factors such as tire material nonlinearity, suspension friction, hydraulic actuator hysteresis, and ambient temperature, there will inevitably be a certain deviation between the theoretical calculation results and the actual measurement results. Therefore, this embodiment introduces force feedback closed-loop control to continuously reduce the vertical force error, making the road simulation device... The output road excitation is closer to the actual road conditions. It can perform feedback control based on the vertical force error and output an additional correction term. The additional correction term is used to further correct the road excitation compensation amount to eliminate the effects of model error, actuator error and parameter changes, so that the system has higher steady-state accuracy and dynamic response capability. Subsequently, the final excitation displacement command is generated based on the original road vertical displacement, total compensation amount and additional correction term, and output to the road simulation device. The road simulation device drives the wheels to produce corresponding vertical motion according to the excitation displacement command, so that the vehicle suspension, tires and body response are closer to the actual road driving state.

[0029] Combination Figure 6 The following provides a specific example of this embodiment: The architecture mainly includes a raw road spectrum database, a road surface adhesion coefficient estimator, a two-way decoupled calculation unit, an online tire model, a chassis system under test on a real vehicle or bench, measured chassis / wheel conditions, and a vibration table / drum actuator. The two-way decoupled calculation unit includes a vertical static indentation calculation module, a slip additional displacement calculation module, a weighted fusion and PI correction module, and a vibration table / drum actuator module. The specific principles are as follows: (1) Signal acquisition and initialization.

[0030] Load the original road surface vertical displacement signal from the original road spectrum database. The sampling time step is Δt = 1ms. The following signals are acquired in real-time from the actual vehicle or test bench: ① Vertical force of wheel (Obtained via wheel hub force sensor or suspension force sensor, unit: N); ②Longitudinal slip ratio κ (dimensionless, calculated from wheel speed and vehicle speed); ③ Lateral slip angle (Unit: rad) ④ Road surface adhesion coefficient (This can be output in real time via a road surface adhesion coefficient estimator based on a vehicle dynamics model).

[0031] (2) Calculation of static tire pressure.

[0032] The vertical static indentation calculation module is based on the tire's vertical stiffness. (Unit: N / m, can be looked up in a table by tire model or calibrated offline), calculate the static compressive displacement caused by vertical force. : ; Physical meaning: When F z When the height is increased, the tire is pressed more into the road surface, and the equivalent road surface bump height that the vibrator should output is reduced accordingly.

[0033] (3) Calculation of additional displacement caused by slippage.

[0034] Define the slip coupling coefficient (Dimensionless, value range 0.03~0.15, calibrated according to tire tread pattern and road surface type), the slip-induced additional displacement calculation module calculates the equivalent displacement correction caused by slip as follows: ; in This is the effective value (root mean square) of the current road spectrum segment, used to normalize the slip correction magnitude.

[0035] (4) Introduce adjustment factors λ1 and λ2 (adaptive weighting based on road surface adhesion coefficient μ).

[0036] Definition of regulation factor: (Vertical force compensation weight); (Slip compensation weight); Where k1 and k2 are calibrable constants (typical values) =2.0, =0.8); High-adhesion pavement (μ≈1.0): ≈1, ≈0, mainly compensating for indentation caused by vertical force; slippage effect is negligible; low-adhesion pavement (μ=0.2): ≈0.20, The weight of slip compensation is approximately 0.64, which is consistent with the physical characteristics of low-adhesion pavements that are prone to slippage.

[0037] (5) Total compensation amount calculate.

[0038] The total compensation amount of weighted fusion and PI correction module Represented as: ; (6) Force closed-loop PI correction based on tire model.

[0039] The weighted fusion and PI correction module adjusts the displacement command z output by the current exciter. cmd (t) (at the previous moment), call the built-in online tire model (a simplified spring-damped model can be used) to estimate the vertical force at this displacement. .

[0040] Based on the actual vertical force And estimated vertical force Calculate the vertical force error: ; Additional correction term for PI controller output : ; in , Adjusted according to parameter calibration, where typical values ​​are... =0.05, =0.01.

[0041] (7) Final excitation displacement command synthesis.

[0042] ; The command is output to the hub controller at a 1ms cycle.

[0043] The vibration table / rotating hub actuator is subjected to physical and mechanical excitation, which causes the chassis system under test on the actual vehicle or bench to generate corresponding suspension movement, wheel movement and vehicle dynamics response, and provides real-time feedback through the measured chassis / wheel status, including measured slip state and measured response feedback.

[0044] Finally, the process is iterated, and steps (1) to (7) are repeated in each control cycle to form a real-time closed loop.

[0045] In this embodiment, the road excitation compensation amount is determined based on the vehicle's operating state, and different compensation amounts are adaptively fused in combination with the road surface adhesion coefficient. At the same time, the error between the actual vertical force and the estimated vertical force is used for feedback control to generate additional correction terms, and finally, the excitation displacement command is generated. This establishes a two-way closed-loop coupling relationship between road excitation and vehicle dynamic response, enabling road excitation to adapt to the contact characteristics between the tire and the road surface under different adhesion conditions. This not only improves the accuracy of road reproduction and reduces the deviation between the vehicle suspension motion response and the actual road conditions, but also improves the reliability of bench verification of different chassis control algorithms and reduces the risk of bench verification passing but real vehicle verification failing.

[0046] Optionally, the tire force state includes the wheel vertical force, the tire slip state includes the longitudinal slip ratio and the lateral slip angle, and the determination of the road excitation compensation amount based on the vehicle operating state includes: S110: Determine the first compensation amount based on the wheel vertical force and tire vertical stiffness.

[0047] Specifically, in combination Figure 2 As shown, the tire stress state during vehicle operation is characterized by wheel vertical force. Wheel vertical force can be directly measured by a wheel hub six-component force sensor, suspension load sensor, and axle force sensor, or estimated by combining suspension displacement, spring stiffness, and vehicle dynamics model. Since tires have a certain radial stiffness, when the vehicle is subjected to a vertical load, the tire undergoes elastic compression, causing the actual tire contact point to change position relative to the original road surface. Therefore, the actual road excitation is not equal to the collected original road spectrum, but should be corrected based on tire deformation. After obtaining the wheel vertical force at the current moment, the tire vertical deformation is calculated based on the corresponding vertical stiffness, and the tire vertical deformation is used as the first compensation amount. The static compression displacement caused by the vertical force (i.e., the first compensation amount) can be expressed as: ; Among them, tire vertical stiffness Offline calibration can be performed based on tire model, or a tire parameter database can be established, with the road simulation controller automatically calling the corresponding parameters before the vehicle enters the test. Tire vertical stiffness can also be set as a dynamic parameter related to tire inflation pressure, ambient temperature, or vehicle load. When the vehicle state changes, the tire vertical stiffness is updated in real time, thereby further improving the accuracy of the first compensation calculation. For example, when the vehicle static load increases, the tire compression increases, and the first compensation increases accordingly; when the tire pressure increases, the tire stiffness increases, and the first compensation corresponding to the same wheel vertical force decreases. By introducing tire vertical stiffness, the actual tire compression under different vehicle operating conditions can be reflected more accurately.

[0048] S120: Determine the second compensation amount based on the longitudinal slip ratio, the lateral slip angle, and the slip coupling coefficient.

[0049] Specifically, in addition to vertical tire compression, slippage occurs between the tire and the road surface during braking, driving, or steering. Tire slippage includes longitudinal slip ratio and lateral slip angle. The longitudinal slip ratio reflects the deviation between the wheel's rolling speed and the vehicle's actual speed; it gradually increases during braking and also causes slippage in the drive wheels during driving. The lateral slip angle represents the angle between the tire's rolling direction and the vehicle's actual direction of motion; it changes continuously during steering due to tire lateral deformation. By acquiring the longitudinal slip ratio and lateral slip angle in real time and combining them with the slip coupling coefficient, a second compensation amount is calculated. The equivalent displacement correction amount caused by slippage (i.e., the second compensation amount) is: ; Slip coupling coefficient Used to describe the impact of different tires and road surfaces on slip compensation, it can be calibrated based on tire tread pattern, tire material, and road type; root mean square value of the current road spectrum segment. This is used to reflect the current degree of road undulation, so that the slip compensation amount can be automatically adjusted as the road grade changes. When the vehicle is traveling on a flat road, even if the slip ratio is large, the second compensation amount remains small. However, when the vehicle is traveling on a road with large undulations, the same slip state will produce a larger compensation amount, making the compensation more in line with the actual situation. In other embodiments, road spectrum energy, road spectrum standard deviation, peak height, or road grade parameters can be used instead of the root mean square value as road characteristic parameters. This invention does not limit this.

[0050] Ultimately, the road simulation controller uses the first compensation amount and the second compensation amount together as the road excitation compensation amount, providing input for the subsequent calculation of the total compensation amount.

[0051] In this optional embodiment, the first compensation amount is determined based on the wheel vertical force and the tire vertical stiffness, and the second compensation amount is determined based on the longitudinal slip ratio, the lateral slip angle, and the slip coupling coefficient. The tire vertical deformation and tire slip are modeled and calculated separately, realizing the decoupling of different influencing factors. This can reflect the different effects of tire force changes and tire slip changes on road input, improve the calculation accuracy of road excitation compensation amount, and provide a more accurate data basis for subsequent total compensation amount calculation.

[0052] Optionally, determining the total compensation amount based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient includes: S210: Determine the first adjustment factor corresponding to the first compensation amount and the second adjustment factor corresponding to the second compensation amount based on the road surface adhesion coefficient.

[0053] Specifically, in combination Figure 3As shown, the influence of tire force and tire slippage on road excitation varies significantly under different road surface adhesion conditions. For example, on dry asphalt roads, the adhesion between the tire and the road surface is strong, and tire slippage is usually small. In this case, the road input is mainly affected by the vertical compression of the tire. However, on snow-covered, wet, or icy roads, tire slippage is more likely to occur, and the impact of tire slippage on road excitation is more significant. Therefore, this embodiment introduces the road surface adhesion coefficient as a basis for compensation adjustment. Based on the road surface adhesion coefficient output by the vehicle dynamics estimator, a first adjustment factor and a second adjustment factor are calculated respectively. Determine as follows: (Vertical force compensation weight); Second regulatory factor Determine as follows: (Slip compensation weight); As can be seen from the above relationship, when the road surface adhesion coefficient gradually increases, the first adjustment factor gradually increases while the second adjustment factor gradually decreases. For example, under high adhesion road surface conditions, the first adjustment factor is close to 1 and the second adjustment factor is close to 0, indicating that road compensation is mainly determined by tire vertical compression. Under low adhesion road surface conditions, the first adjustment factor decreases and the second adjustment factor increases, indicating that the system pays more attention to the impact of tire slippage on road excitation. Therefore, the compensation strategy can automatically switch with the road environment, improving the accuracy of road simulation.

[0054] S220: Determine the vertical force compensation amount based on the first compensation amount and the first adjustment factor, determine the slip compensation amount based on the second compensation amount and the second adjustment factor, and determine the total compensation amount based on the vertical force compensation amount and the slip compensation amount.

[0055] Specifically, the two compensation amounts are weighted using the first and second adjustment factors respectively, and the total compensation amount can be expressed as: ; The first term on the right is based on the first compensation amount. and the first regulatory factor The determined vertical force compensation amount, the second item is based on the second compensation amount. Second regulatory factor Given a determined slip compensation amount, the total compensation amount is obtained by adding the vertical force compensation amount and the slip compensation amount. .

[0056] By employing the aforementioned weighted fusion method, tire vertical deformation compensation and tire slip compensation can be dynamically allocated based on real-time road surface adhesion conditions, eliminating the need for separate control strategies for different roads. For instance, when a vehicle transitions from a dry asphalt road to a wet, slippery road, the road simulation controller automatically reduces the vertical force compensation ratio and increases the slip compensation ratio based on changes in the adhesion coefficient, ensuring that the generated total compensation accurately reflects the vehicle's current tire-road contact state. Compared to traditional RiL testing methods that only correct road input based on a fixed ratio, this embodiment can adjust the compensation strategy in real time based on tire force state, tire slip state, and road surface adhesion state. This makes the road excitation closer to the equivalent road input experienced by the tire contact point under real road conditions, improving road simulation accuracy and providing a more accurate compensation basis for subsequent force feedback closed-loop control and excitation displacement command generation.

[0057] In this optional embodiment, the first adjustment factor and the second adjustment factor are determined according to the road surface adhesion coefficient, and the total compensation amount is obtained by calculating the vertical force compensation amount and the slip compensation amount respectively. This allows the compensation amount from different sources to be adaptively allocated according to the real-time road surface condition. It can automatically adjust the contribution ratio between tire vertical deformation compensation and tire slip compensation according to the road surface adhesion conditions, improve the adaptability of the road excitation compensation strategy to different road environments, and further improve the road reproduction accuracy.

[0058] Optionally, the first adjustment factor is positively correlated with the road surface adhesion coefficient, and the second adjustment factor is negatively correlated with the road surface adhesion coefficient.

[0059] Specifically, the contact state between the tire and the road surface varies significantly when a vehicle travels under different road conditions. Therefore, the contribution ratio of the first compensation amount to the total compensation amount should be dynamically adjusted according to the change in road adhesion capability. The first adjustment factor can be calculated in real time based on the road adhesion coefficient output by the vehicle dynamics estimator. The road adhesion coefficient can be obtained through tire force estimation algorithms, longitudinal dynamic models, lateral dynamic models, or fusion estimation algorithms, or it can be preset according to the test conditions. When the road adhesion coefficient is high, such as when the vehicle is traveling on dry asphalt roads or cement roads, the adhesion capability between the tire and the road surface is strong, and tire slippage is more likely. Since such phenomena are relatively rare, the actual road input of the vehicle is mainly determined by the vertical compression of the tires. Therefore, the road simulation controller increases the first adjustment factor to increase the proportion of the first compensation amount in the total compensation amount. As the road surface adhesion coefficient decreases, for example, when the vehicle enters a wet, slippery, snowy, or icy road surface, the tires are more likely to slip, and the impact of the vertical compression of the tires on the road input is relatively weakened. Therefore, the road simulation controller gradually decreases the first adjustment factor to reduce the contribution ratio of the first compensation amount in the total compensation amount. Preferably, the first adjustment factor can be obtained by using an exponential function, a linear function, a piecewise function, or a lookup table method, and this invention does not limit this.

[0060] Unlike the first adjustment factor, the second adjustment factor is mainly used to adjust the slip compensation amount. It can be calculated based on the real-time road surface adhesion coefficient and gradually increases as the road surface adhesion coefficient decreases. For example, when a vehicle enters a low-adhesion road surface, the tires are more prone to longitudinal and lateral slippage. Therefore, the road simulation controller automatically increases the second adjustment factor, making the slip compensation amount account for a higher proportion of the total compensation, thus more accurately reflecting the equivalent road input changes caused by tire slippage. Conversely, when the vehicle returns to a high-adhesion road surface, tire slippage decreases significantly, and the road simulation controller automatically decreases the second adjustment factor to avoid excessive slip compensation affecting the road reproduction accuracy. Therefore, through the inverse relationship between the first and second adjustment factors, the automatic switching of road excitation compensation strategies under different road adhesion conditions is achieved, improving the system's adaptability to complex road environments.

[0061] In this optional embodiment, by setting a first adjustment factor that is positively correlated with the road surface adhesion coefficient and a second adjustment factor that is negatively correlated with the road surface adhesion coefficient, the system can automatically adjust the weight of different compensation amounts as the road surface adhesion conditions change. When the vehicle is traveling on a high-adhesion road surface, the influence of tire vertical deformation compensation is increased; when the vehicle is traveling on a low-adhesion road surface, the influence of tire slippage compensation is increased. This makes the compensation strategy more consistent with the actual contact law between the tire and the road surface, and improves the realism and stability of the road simulation results.

[0062] Optionally, the step of determining the additional correction term based on the feedback control of the error between the actual vertical force and the estimated vertical force includes: S310: Determine the vertical force error based on the actual vertical force and the estimated vertical force.

[0063] Specifically, in combination Figure 4 As shown, after calculating the total compensation, a force feedback closed loop is further established. Based on the excitation displacement command at the current moment, the corresponding estimated vertical force is calculated using the tire model. The tire model can be a linear spring model, a spring-damped model, a Magic Formula tire model, an FTire tire model, or other models that can describe the vertical force characteristics of the tire. In this embodiment, a spring-damped model is preferred to balance computational efficiency and control real-time performance. At the same time, the actual vertical force of the vehicle is collected in real time, and the actual vertical force is compared with the estimated vertical force to obtain the vertical force error corresponding to the current control cycle. If the vertical force error is large, it indicates that the road excitation output by the current road simulation device cannot accurately reproduce the real road input, and the excitation displacement needs to be further corrected. If the vertical force error approaches zero, it indicates that the tire model prediction result is basically consistent with the actual measurement result, and the road excitation reproduction accuracy is high.

[0064] S320: Input the vertical force error into the proportional-integral controller to determine the additional correction term.

[0065] Specifically, after obtaining the vertical force error, the road simulation controller inputs the vertical force error into the proportional-integral (PI) controller. The PI controller outputs an additional correction term based on the current error and the cumulative value of historical errors. The proportional component responds quickly to the current error, enabling the system to correct the road excitation in a timely manner; the integral component continuously corrects the steady-state deviation based on historical errors, ultimately achieving zero steady-state error control. Preferably, the output of the PI controller can be expressed as: ; The proportional and integral coefficients can be calibrated according to different vehicle models, tire models, and road simulation devices, or they can be adjusted online according to the system's operating status. By introducing force feedback closed-loop control, this embodiment can further eliminate tire model errors, parameter drift, and road simulation device execution errors, thereby improving the long-term operational stability of the road simulation system.

[0066] In this optional embodiment, the vertical force error is determined based on the actual vertical force and the estimated vertical force, and the vertical force error is input into the proportional-integral controller to determine the additional correction term, so that the road simulation system is transformed from traditional open-loop control to force feedback closed-loop control. Since the proportional-integral controller can simultaneously take into account the dynamic response speed and steady-state control accuracy of the system, it can continuously reduce the impact of tire model error, road simulation device execution error and parameter drift, improve the excitation displacement control accuracy, and make the simulated tire vertical load closer to the real vehicle operating state.

[0067] Optionally, generating the excitation displacement command based on the original road surface vertical displacement, the total compensation amount, and the additional correction term includes: S330: The original vertical displacement of the road surface is compensated according to the total compensation amount to obtain the compensated road surface displacement.

[0068] Specifically, in combination Figure 5 As shown, the original vertical displacement of the road surface at the current moment is read, and then the original vertical displacement of the road surface is corrected according to the total compensation amount. Since the total compensation amount takes into account the vertical deformation of the tire, tire slippage and road surface adhesion conditions, the compensated road surface displacement can more accurately reflect the equivalent road input experienced by the actual contact point of the vehicle. For example, during the braking process of the vehicle, due to the compression of the tire and the accompanying slippage, the compensated road surface displacement is adjusted accordingly compared with the original road surface displacement, so as to output a more realistic road excitation.

[0069] S340: Generate the excitation displacement command based on the compensated road surface displacement and the additional correction term.

[0070] Specifically, after road surface displacement compensation is completed, the final excitation displacement command is generated by combining additional correction terms. The compensated road surface displacement is mainly used to compensate for road input errors caused by changes in tire contact state, while the additional correction terms are mainly used to compensate for model errors and control errors. Therefore, the two parts of compensation work together on the original road excitation, so that the final generated excitation displacement command can reflect the real road geometry and ensure that the actual tire force is consistent with the theoretical force. The generated excitation displacement command is sent to the road simulation controller according to the preset control cycle to realize real-time control of the road simulation device.

[0071] In this optional embodiment, the original road surface vertical displacement is first corrected using the total compensation amount, and then an excitation displacement command is generated by combining the additional correction term. This allows road geometric compensation and force feedback compensation to work together in the road excitation generation process, which can simultaneously correct road input errors and control errors, improve the accuracy of the excitation displacement command, and thus improve the realism of the road excitation output by the road simulation device.

[0072] Optionally, the road spectrum in-loop testing method further includes: inputting the excitation displacement command into a road simulation controller to drive the vehicle to reproduce the road spectrum.

[0073] Specifically, the road simulation controller receives the excitation displacement command output by the road excitation calculation module and converts the control quantity according to the control mode of the road simulation device. For example, when the road simulation device is a hydraulic vibrator, the road simulation controller converts the excitation displacement command into a hydraulic servo valve control signal to drive the hydraulic cylinder to output the corresponding displacement. When the road simulation device is an electric actuator, it is converted into a motor control command to achieve the corresponding displacement control. When the road simulation device is a rotating hub test bench, it is converted into a rotating hub lifting control command to enable the wheel to obtain the corresponding road excitation.

[0074] In this optional embodiment, by inputting the excitation displacement command into the road simulation controller, the road simulation device can reproduce the road spectrum of the vehicle, enabling the vehicle's operating status to be continuously fed back to the road simulation controller to form real-time closed-loop control. This is applicable not only to different types of road simulation devices such as hydraulic exciters, four-column road simulation benches, six-degree-of-freedom road simulation platforms, and rotating hub test benches, but also to continuously updating the road excitation throughout the entire road simulation process, improving the system's real-time performance and road reproduction stability, thereby meeting the high-precision road simulation requirements for the development and verification of vehicle chassis dynamics control systems.

[0075] like Figure 7 As shown, an embodiment of the present invention provides a road spectrum loop-in-the-loop testing device 700, comprising: The first module 710 is used to determine the road excitation compensation amount based on the vehicle operating state, the vehicle operating state including the tire force state and the tire slip state, and the road excitation compensation amount including a first compensation amount generated by the vertical deformation of the tire and a second compensation amount generated by the tire slip. The second module 720 is used to determine the total compensation amount based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient. The third module 730 is used to determine additional correction terms based on feedback control according to the error between the actual vertical force and the estimated vertical force, and to generate excitation displacement commands based on the original road surface vertical displacement, the total compensation amount and the additional correction terms.

[0076] like Figure 8 As shown, an electronic device 800 provided in this embodiment of the invention includes a memory 820 and a processor 810; the memory 820 is used to store a computer program; the processor 810 is used to implement the road spectrum loop-in-the-loop testing method as described above when the computer program is executed.

[0077] Alternatively, an electronic device 800 includes a memory 820 and a processor 810 coupled to the memory 820; the memory 820 is configured to store a computer program; and the processor 810 is configured to perform the following operations when the computer program is executed: The road excitation compensation amount is determined based on the vehicle's operating state, which includes the tire's force state and tire slippage state. The road excitation compensation amount includes a first compensation amount generated by the tire's vertical deformation and a second compensation amount generated by the tire slippage. The total compensation amount is determined based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient; Feedback control is used to determine additional correction terms based on the error between the actual vertical force and the estimated vertical force. Excitation displacement commands are generated based on the original road surface vertical displacement, the total compensation amount, and the additional correction terms.

[0078] This invention provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the road spectrum loop-in-the-loop testing method described above.

[0079] Alternatively, a non-volatile computer-readable storage medium storing a computer program that, when executed by a processor, causes the processor to perform the following operations: The road excitation compensation amount is determined based on the vehicle's operating state, which includes the tire's force state and tire slippage state. The road excitation compensation amount includes a first compensation amount generated by the tire's vertical deformation and a second compensation amount generated by the tire slippage. The total compensation amount is determined based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient; Feedback control is used to determine additional correction terms based on the error between the actual vertical force and the estimated vertical force. Excitation displacement commands are generated based on the original road surface vertical displacement, the total compensation amount, and the additional correction terms.

[0080] The present invention will now be described an electronic device 800 that can serve as a server or client of the present invention, which is an example of a hardware device that can be applied to various aspects of the present invention. Electronic device 800 is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic device 800 can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0081] Electronic device 800 includes a computing unit that can perform various appropriate actions and processes based on a computer program stored in read-only memory (ROM) or a computer program loaded from a storage unit into random access memory (RAM). The RAM may also store various programs and data required for device operation. The computing unit, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0082] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc. In this application, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the embodiments of the present invention according to actual needs. Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated units can be implemented in hardware or as software functional units.

[0083] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A method for loop-in-the-loop testing of road spectrum, characterized in that, include: The road excitation compensation amount is determined based on the vehicle's operating state, which includes the tire's force state and tire slippage state. The road excitation compensation amount includes a first compensation amount generated by the tire's vertical deformation and a second compensation amount generated by the tire slippage. The total compensation amount is determined based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient; Feedback control is used to determine additional correction terms based on the error between the actual vertical force and the estimated vertical force. Excitation displacement commands are generated based on the original road surface vertical displacement, the total compensation amount, and the additional correction terms.

2. The road spectrum loop-in-the-loop testing method according to claim 1, characterized in that, The tire force state includes the wheel vertical force, the tire slip state includes the longitudinal slip ratio and the lateral slip angle, and the determination of the road excitation compensation amount based on the vehicle operating state includes: The first compensation amount is determined based on the wheel vertical force and the tire vertical stiffness; The second compensation amount is determined based on the longitudinal slip ratio, the lateral slip angle, and the slip coupling coefficient.

3. The road spectrum loop-in-the-loop testing method according to claim 1, characterized in that, The determination of the total compensation amount based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient includes: Determine a first adjustment factor corresponding to the first compensation amount and a second adjustment factor corresponding to the second compensation amount based on the road surface adhesion coefficient; The vertical force compensation amount is determined based on the first compensation amount and the first adjustment factor, the slip compensation amount is determined based on the second compensation amount and the second adjustment factor, and the total compensation amount is determined based on the vertical force compensation amount and the slip compensation amount.

4. The road spectrum loop-in-the-loop testing method according to claim 3, characterized in that, The first adjustment factor is positively correlated with the road surface adhesion coefficient, and the second adjustment factor is negatively correlated with the road surface adhesion coefficient.

5. The road spectrum loop-in-the-loop testing method according to claim 1, characterized in that, The method of determining additional correction terms based on feedback control according to the error between the actual vertical force and the estimated vertical force includes: The vertical force error is determined based on the actual vertical force and the estimated vertical force. The vertical force error is input into the proportional-integral controller to determine the additional correction term.

6. The road spectrum loop-in-the-loop testing method according to claim 1, characterized in that, The process of generating the excitation displacement command based on the original road surface vertical displacement, the total compensation amount, and the additional correction term includes: The original vertical displacement of the road surface is compensated based on the total compensation amount to obtain the compensated road surface displacement; The excitation displacement command is generated based on the compensated road surface displacement and the additional correction term.

7. The road spectrum loop-in-the-loop testing method according to any one of claims 1 to 6, characterized in that, Also includes: The excitation displacement command is input into the road simulation controller to drive the vehicle to reproduce the road spectrum.

8. A road spectrum loop-in-the-loop testing device, characterized in that, include: The first module is used to determine the road excitation compensation amount based on the vehicle operating state, which includes the tire force state and the tire slip state. The road excitation compensation amount includes a first compensation amount generated by the vertical deformation of the tire and a second compensation amount generated by the tire slip. The second module is used to determine the total compensation amount based on the first compensation amount, the second compensation amount, and the road surface adhesion coefficient. The third module is used to determine additional correction terms based on feedback control according to the error between the actual vertical force and the estimated vertical force, and to generate excitation displacement commands based on the original road surface vertical displacement, the total compensation amount and the additional correction terms.

9. An electronic device, characterized in that, Including memory and processor; The memory is used to store computer programs; The processor is configured to implement the road spectrum loop-in-the-loop testing method as described in any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program that, when executed by a processor, implements the road spectrum loop-in-the-loop testing method as described in any one of claims 1 to 7.

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