Vehicle roll angle estimation method, system, electronic device and vehicle

Abstract

The present invention discloses a vehicle roll angle estimation method, system, electronic device and vehicle, including a signal processing module, a suspension parameter calculation module, a wheel center roll angle estimation module, a stabilizer bar real-time contribution roll moment back calculation module, and a vehicle relative to the ground steady-state body roll angle estimation module. The above modules are used to calculate the vehicle relative to the ground steady-state body roll angle in real time, which is used to implement the steady-state body roll angle control strategy. The present invention can improve the accuracy of estimation and reduce the cost of use, and provide for subsequent steady-state body roll control, so that the vehicle has better body anti-roll performance in steady-state driving conditions.

Description

Technical Field

[0001] The present invention relates to the field of automobile body related control, and in particular to vehicle roll control technology. Background Art

[0002] With the popularization of the new four trends of automobiles (electrification, intelligence, networking, and sharing), users' requirements for vehicle performance have been greatly improved. At present, the higher the requirements for vehicle performance, the richer the scenarios that the control algorithms related to vehicle performance must rely on, and the closer they are to the actual scenarios. Controlling the steady-state body roll of a vehicle usually includes two aspects: steady-state body roll angle estimation and steady-state body roll angle control. Steady-state body roll angle estimation is the input condition for steady-state body roll angle control. The more accurate and closer to reality the steady-state body roll angle estimation is, the more conducive it is to subsequent control parameter setting and ensuring the effectiveness of the algorithm. In steady-state body roll angle control, it is necessary to estimate the steady-state body roll angle of the vehicle in real time, and use the estimated result as the input of steady-state body roll angle control. Therefore, the accuracy of the roll angle estimation, the complexity of the process, etc., will directly affect the accuracy of the body roll angle control and the difficulty of implementation.

[0003] In the prior art, the vehicle body roll angle estimation is mostly directly tested by gyroscopes and roll angle sensors. For example, patent document 201810128235.7 discloses an active lateral stabilizer bar and its control method. This direct testing method has a high demand for the vehicle body roll angle sensor, and the gyroscope is currently commonly used in the market. The higher the accuracy, the higher the cost, which is not conducive to mass production of products. For example, patent document 201410281621.1 discloses a vehicle roll angle and pitch angle estimation method based on Kalman filtering, which measures the lateral acceleration, vehicle speed, etc., and then uses Kalman filtering to estimate the unknown parameter roll angle. However, in complex road environments, some external non-random interferences such as sensor failures, collisions and other extreme situations often affect the estimation effect of the Kalman filter algorithm. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a vehicle roll angle estimation method, system, electronic equipment and vehicle, aiming to improve the estimation accuracy and reduce the cost of use, and provide for subsequent vehicle body steady-state roll control, so that the vehicle body has better anti-roll performance under steady-state driving conditions.

[0005] The technical solution of the present invention is as follows:

[0006] The present invention provides a vehicle roll angle estimation method, comprising the following steps:

[0007] Step 1: Signal processing: Collect the vehicle height signal and the torque signal returned by the active stabilizer bar, and perform filtering.

[0008] Step 2: Estimation of the roll angle at the wheel center: Calculate the roll angle generated by the suspension using the vehicle height signal.

[0009] Step 3, suspension parameter calculation: Calculate suspension component parameters to system-level parameters based on vehicle mass parameters, vehicle size parameters, elastic component parameters, and hard point related parameters (such as stabilizer bar leverage ratio, etc.), including suspension stiffness, suspension roll stiffness, tire contribution roll stiffness, and vehicle roll arm.

[0010] Step 4: Back-calculate the anti-roll moment contributed by the stabilizer bar in real time: Back-calculate the anti-roll moment contributed by the stabilizer bar to the front and rear axles based on the torque provided by the active stabilizer bar in real time.

[0011] Step 5, estimation of the steady-state body roll angle of the vehicle relative to the ground: mainly used to estimate the total body roll angle relative to the ground. The total body roll angle relative to the ground is obtained by the sum of the roll angle at the wheel center and the tire contribution roll angle. The steady-state body roll angle estimation module of the vehicle relative to the ground includes calculating the front and rear axle anti-roll moment through the output parameters of the suspension parameter calculation module, the stabilizer bar contribution anti-roll moment module, and the wheel center roll angle estimation module; wherein the front and rear axle anti-roll moment is the sum of the front and rear axle anti-roll moment contributed by the stabilizer bar and the suspension contribution anti-roll moment. The suspension contribution anti-roll moment is the product of the suspension roll stiffness and the wheel center roll angle. The tire contribution roll angle is the front and rear axle anti-roll moment divided by the tire roll stiffness.

[0012] The above method steps are used to calculate the steady-state body roll angle of the vehicle relative to the ground in real time, which is used to implement the steady-state body roll angle control strategy.

[0013] On the other hand, the present application also provides a vehicle roll angle estimation system, including a signal processing module, a suspension parameter calculation module, a wheel center roll angle estimation module, a stabilizer bar real-time contribution roll moment back calculation module, and a vehicle relative to the ground steady-state body roll angle estimation module. The above modules are used to calculate the vehicle relative to the ground steady-state body roll angle in real time for the implementation of a steady-state body roll angle control strategy.

[0014] The signal processing module is used to collect the vehicle height signal and the torque signal returned by the active stabilizer bar, and perform filtering processing.

[0015] The wheel center roll angle estimation module is used to calculate the roll angle generated by the suspension using the vehicle height signal.

[0016] The suspension parameter calculation module is used to calculate suspension component parameters to system-level parameters according to vehicle mass parameters, vehicle size parameters, elastic element parameters, and hard point related parameters, including suspension stiffness, suspension roll stiffness, tire contribution roll stiffness, and vehicle roll arm.

[0017] The stabilizer bar real-time contribution roll moment back-calculation module is used to back-calculate the front and rear axle anti-roll moment contributed by the stabilizer bar based on the torque provided by the active stabilizer bar in real time.

[0018] The vehicle steady-state body roll angle estimation module relative to the ground is used to estimate the total vehicle steady-state body roll angle relative to the ground, and the total body roll angle relative to the ground is obtained by the sum of the roll angle at the wheel center and the tire contribution roll angle; the tire contribution roll angle is the front and rear axle anti-roll moment divided by the tire roll stiffness, the front and rear axle anti-roll moment is the sum of the front and rear axle anti-roll moment contributed by the stabilizer bar and the suspension contribution anti-roll moment, and the suspension contribution anti-roll moment is the product of the suspension roll stiffness and the roll angle at the wheel center.

[0019] In a third aspect of the present application, an electronic device is provided, comprising:

[0020] One or more processors; a storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, the electronic device implements the vehicle roll angle estimation method described above.

[0021] In a fourth aspect, the present application further provides a vehicle, wherein the vehicle is equipped with the above-mentioned electronic device.

[0022] The beneficial effects of the present invention are as follows:

[0023] 1. The present invention proposes a vehicle roll angle estimation method, which does not use roll angle related sensors such as gyroscopes, nor does it use complex filtering algorithms for estimation. Under the premise of guaranteed accuracy, the cost is more favorable, which provides better guarantee for subsequent mass production. At the same time, a height sensor is used to estimate the roll angle at the wheel center, and the roll angle is divided into two parts, the wheel center (suspension) and the tire for calculation. The closed loop uses the stabilizer bar torque to calculate the roll angle, which is highly robust and accurate.

[0024] 2. The vehicle roll angle estimation of the present invention, when estimating the steady-state body roll angle of the vehicle relative to the ground, is performed from the component level to the system level to the vehicle level, such as Figure 5 The flow chart shows that the steady-state body roll angle of the vehicle relative to the ground is decomposed into two parts, one part is the suspension contribution roll angle (roll angle at the wheel center), and the other part is the tire contribution roll angle. This is a more accurate method. At the same time, the suspension contribution roll angle is calculated through the height sensor test data, and the tire contribution roll angle is calculated by the active stabilizer bar return torque. The test data is combined with the estimated data to further enhance the accuracy of the steady-state body roll angle estimation of the vehicle relative to the ground. It is used as the input of the subsequent roll control, and the anti-roll torque of the whole vehicle is output through the subsequent control algorithm. The steady-state body roll control technology under the vehicle performance calibration can ensure that the other vehicle performance is better while controlling the roll angle.

[0025] 3. The vehicle roll angle estimation method of the present invention has a fast algorithm response, is easy to implement, and has high robustness for mass-produced models. It is convenient for subsequent controller hardware design and is more easily adopted by OEMs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a vehicle demonstration functional block diagram for steady-state body roll control;

[0027] Figure 2 It is a principle block diagram of the vehicle roll angle estimation proposed by the present invention;

[0028] Figure 3 It is a principle block diagram of combining the vehicle roll angle estimation system proposed by the present invention with the subsequent steady-state vehicle body roll control;

[0029] Figure 4 yes Figure 3 Signal flow diagram of the entire steady-state body roll control;

[0030] Figure 5 It is the forward decomposition flow chart of vehicle roll control;

[0031] Figure 6 yes Figure 2 The principle block diagram of the wheel center roll angle estimation module;

[0032] Figure 7 yes Figure 2 The principle block diagram of the vehicle relative to the ground steady-state body roll angle estimation module in FIG.

[0033] Figure 8 yes Figure 3 Principle block diagram of the total anti-roll moment calculation module of the vehicle;

[0034] Fig. 9 yes Figure 3 Principle block diagram of the vehicle total anti-roll moment calculation module and the sub-module of the real vehicle anti-roll moment control module;

[0035] Fig.10 yes Figure 3 Principle block diagram of the front and rear anti-roll moment distribution coefficient calculation module. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. It should be understood that the present application can also be implemented or applied through other different specific implementation methods, and the various forms of processes shown below can be used to reorder, add or delete steps. For example, the steps recorded in this application can be executed in parallel, can be executed sequentially, or can be executed in different orders, as long as the desired results of the technical solutions disclosed in this application can be achieved, and this document is not limited here.

[0037] The following embodiment applies the vehicle roll angle estimation method and system protected by the present invention to the steady-state roll control of the entire vehicle body. It shows in detail the two parts of the steady-state roll control of the vehicle body, including vehicle roll angle estimation and steady-state roll control of the vehicle body. The overall control includes: the vehicle estimates the roll angle of the vehicle body in real time based on the height sensor signal, steering wheel angle signal, vehicle speed signal, steering wheel angular velocity signal, lateral acceleration signal and yaw angular velocity signal, combined with vehicle mass parameters and system component parameters, and compares it with the ideal roll angle, and outputs the anti-roll torque of the whole vehicle through the PD control algorithm with variable control parameters; based on the difference between the ideal yaw angular velocity and the actual yaw angular velocity, it controls the output of the front and rear anti-roll torque distribution coefficients, and uses the forward decomposition technology of the whole vehicle to decompose from top to bottom to generate the front and rear stabilizer bar torques.

[0038] The following is a complete vehicle body steady-state roll control system to explain in detail the implementation of the vehicle body steady-state roll control method:

[0039] like Figure 1 Shown is an illustrative example of a vehicle 10 including a steady-state body roll control module 60 .

[0040] In this embodiment, the signal acquisition module includes four height sensors 11, 21, 31, and 41 installed on the wheels, and the steering wheel angle signal, steering wheel speed signal, vehicle speed signal, and lateral acceleration signal and yaw rate signal tested in IMU (not shown) in the vehicle CAN signal (not shown) transmitted by the OBD interface. Among them, the height sensor 11 is used to measure the relative height signal of the front left suspension to the vehicle body at each moment and transmit it to the control module 60. The height sensor 21 is used to measure the relative height signal of the front right suspension to the vehicle body at each moment and transmit it to the control module 60. The height sensor 31 is used to measure the relative height signal of the rear left suspension to the vehicle body at each moment and transmit it to the control module 60. The height sensor 41 is used to measure the relative height signal of the rear right suspension to the vehicle body at each moment and transmit it to the control module 60. The OBD interface directly obtains the steering wheel angle signal, steering wheel speed signal, vehicle speed signal, and lateral acceleration signal and yaw rate signal tested in IMU in the vehicle CAN signal.

[0041] The control module 60 includes two aspects: one is the estimation of the roll angle of the vehicle body relative to the ground; the second is the implementation method of the steady-state body roll control strategy. The steady-state body roll of the vehicle is controlled to output the anti-roll torque of the whole vehicle. By using the forward decomposition technology of the whole vehicle, the front and rear stabilizer bar torque signals are decomposed from top to bottom and transmitted to the front and rear stabilizer bar motors 12 and 22. The motors 12 and 22 respectively operate the front and rear active stabilizer bars 15 and 25 to adjust the performance of the vehicle. Among them, the motor 12 is the actuator to realize the required front stabilizer bar torque; the motor 22 is the actuator to realize the required rear stabilizer bar torque.

[0042] like Figure 3 As shown, the block diagram shows Figure 1 In various embodiments, the control module 60 may include one or more submodules and a data storage device. It is understood that Figure 2 The submodules shown can be combined and / or further divided to generate stabilizer bar torque signals for steady-state body roll control in a similar manner. The signals input to the control module 60 can be provided by the left front height sensor 11, the right front height sensor 21, the left rear height sensor 31, the right rear height sensor 41, the steering wheel angle signal, the steering wheel speed signal, the vehicle speed signal, the lateral acceleration signal, the yaw rate signal, etc. output by the OBD interface signal of the vehicle 10, and can also be provided by other control modules (not shown) of the vehicle 10, can be modeled, and, or pre-defined.

[0043] In one example, the control module 60 includes two modules: a vehicle roll angle estimation module M60 - 1 and a steady-state vehicle body roll angle control module M60 - 2 .

[0044] The vehicle roll angle estimation module M60-1 is the focus of the present invention. Figure 2 It includes a signal processing module M609-1, a roll angle estimation module M601 at the wheel center, a suspension parameter calculation module M602, a stabilizer bar real-time contribution roll moment back calculation module M603, and a vehicle relative to the ground steady-state body roll angle estimation module M604.

[0045] The steady-state vehicle roll angle control module M60-2 includes a signal processing module M609-2, an ideal roll angle calculation module M605, a vehicle anti-roll moment calculation module M606, a front and rear anti-roll moment distribution coefficient calculation module M607, and a front and rear stabilizer bar required torque calculation module M608.

[0046] In the vehicle roll angle estimation module M60-1, the first signal processing module M609-1 uses low-pass filtering to process the signals S35, S45, S55, and S65 from the four height sensors and transmits them to the wheel center roll angle estimation module M601. Figure 4 shown.

[0047] In the estimation of steady-state body roll angle, various parameters are needed to calculate the suspension parameters, including vehicle mass parameter C63, vehicle size parameter C53, elastic element parameter C43, hard point related parameter C33, etc.

[0048] In this embodiment, the vehicle mass parameter C63 includes parameters such as vehicle mass, front and rear axle loads, and vehicle center of mass height. The vehicle size parameter C53 includes parameters such as front and rear track and wheelbase; the elastic element parameter C43 includes parameters such as spring stiffness, bushing parasitic stiffness, buffer block stiffness, tire radial stiffness, stabilizer bushing stiffness, etc. The hard point related parameters C33 include parameters such as spring lever ratio, stabilizer bar lever ratio, stabilizer bar knuckle arm length, front axle roll center height, etc. They are all used by the suspension parameter calculation module M602 to calculate system-level parameters such as suspension stiffness, suspension contribution roll stiffness, tire contribution roll stiffness, and vehicle roll lever arm.

[0049] In this embodiment, the stabilizer bar real-time contribution roll moment back calculation module M603 calculates the stabilizer bar contribution anti-roll moment at each moment using the torque signals returned from the front and rear stabilizer bar motors.

[0050] Finally, the calculation results of the above modules M601, M602, and M603 are sent to the vehicle's steady-state body roll angle relative to the ground estimation module M604 to calculate the vehicle's anti-roll moment at each moment, the tire contribution roll angle, and the body's roll angle relative to the ground.

[0051] like Figure 2 and Figure 3As shown, the calculation result of each moment in the vehicle roll angle estimation module M60-1 is sent to the steady-state vehicle roll angle control module M60-2. In the steady-state vehicle roll angle control module M60-2, the first signal processing module M609-2 performs low-pass filtering on the steering wheel angle signal S21, the vehicle speed signal S31, the lateral acceleration signal S41, the steering wheel speed signal S51, and the yaw rate signal S61. The first signal processing module M609-2 sends the direction angle signal S21 and the vehicle speed signal S31 to the ideal roll angle calculation module M605. The ideal roll angle calculation module M605 transmits the calibrated ideal roll angle related to the steering wheel angle and vehicle speed to the vehicle total anti-roll moment calculation module M606, and controls the difference between the actual vehicle steady-state roll angle and the ideal roll angle within 0.05° (variable) through the PD control of the adjustable control parameter, and inputs the vehicle total anti-roll moment to the front and rear stabilizer bar required torque calculation module M608. In addition, the first signal processing module M609-2 transmits the processed yaw angle signal S61, the vehicle speed signal S31, and the steering wheel angle signal S21 to the front and rear anti-roll moment distribution coefficient calculation module M607, and controls the theoretical yaw rate and the actual vehicle yaw rate interpolation within 1° / s (variable) through D control, and transmits the front and rear anti-roll moment distribution coefficient to the front and rear stabilizer bar required torque calculation module M608. The front and rear stabilizer bar required torque calculation module M608 calculates the front and rear axle anti-roll moment through the anti-roll moment from the vehicle total anti-roll moment calculation module M606 and the anti-roll moment distribution coefficient from the front and rear anti-roll moment distribution coefficient calculation module M607, and decomposes the suspension parameters calculated by the suspension parameter calculation module M602 from the top to the bottom of the vehicle to obtain the front and rear stabilizer bar motor torque S18, S28, and returns to Figure 1 The front and rear motors in vehicle example 10 trigger the movement of the front and rear stabilizer bars to achieve steady-state anti-roll control of the vehicle. Figure 4 As shown in the signal flow diagram, Figure 3 An illustrative example of the control module 60 is shown in FIG.

[0052] like Figure 6 As shown in the control block diagram, the embodiment of the wheel center roll angle estimation module M601 is given. The four height sensor signals S35, S45, S55, and S65 after low-pass filtering by the signal processing module M609-1 are input into the wheel center roll angle estimation module M601. It can be calculated by the following formula:

[0053]

[0054] in, is the roll angle at the front axle wheel center, H LfwcThe front left wheel center compression is the measurement data of the height sensor S35, H Rfwc is the front right wheel center compression, i.e. the measurement data of the height sensor S55, T fw The front track is set externally by the vehicle dimension parameter C53. Similarly, the roll angle at the rear wheel center The same principle is used to calculate the roll angle of the vehicle body at the wheel center. The average value of the roll angle at the front and rear wheel centers is obtained from formula (2).

[0055]

[0056] In the steady-state vehicle body roll angle estimation module M60-1, the suspension parameter calculation module M602 provides calculations of the front and rear suspension stiffness, the suspension contribution roll stiffness, the front and rear tire contribution roll stiffness, and the roll lever arm.

[0057] The anti-roll moment contribution of the stabilizer bar in real time is calculated by the module M603, in which the anti-roll moment of the front and rear axles contributed by the stabilizer bar is calculated by the following formula:

[0058]

[0059] Among them, M ARB The anti-roll moment of the front and rear axles contributed by the stabilizer bar; T ARB Feedback torque signals S27 and S17 for the front and rear stabilizer bar motors; T w is the vehicle wheelbase; l ARB_arm is the stabilizer lever arm; i ARB is the stabilizer bar wheel center leverage ratio.

[0060] like Figure 7As shown, the control block diagram gives an embodiment of the vehicle relative to the ground steady-state body roll angle estimation module M604. The stabilizer bar real-time contribution roll moment back calculation module M603 calculates the front and rear axle anti-roll moments S603-1 and S603-2 contributed by the stabilizer bar; the wheel center roll angle estimation module M601 calculates the front and rear wheel center roll angles S601-1 and S601-2; the suspension parameter calculation module M602 calculates the front and rear suspension stiffness S602-1 and S602-2 and the front and rear tire roll stiffness S602-3 and S602-4 (considering the system performance change after tire replacement, the front and rear tire equivalent coefficients are added for estimation); the above signals are all input into the vehicle relative to the ground steady-state body roll angle estimation module M604 for calculation. Under steady-state conditions, the steady-state body roll angle S604-1 of the vehicle relative to the ground is composed of the sum of the roll angle at the wheel center and the tire contribution roll angle. In order to avoid the influence of subsequent tire replacement on the estimation, the algorithm adds a tire equivalent coefficient for calibration, and considers the front and rear separately, that is, the front tire equivalent coefficient and the rear tire equivalent coefficient in the figure, and takes the average of the front and rear roll angles. This makes the estimation model more accurate. The difference between the measured and estimated values ​​is verified to be within 0.02° (variable).

[0061] return Figure 4 In the steady-state vehicle body roll angle control module M60-2, the ideal roll angle calculation module M605 establishes a three-dimensional relationship with the ideal roll angle perceptible to the user based on the steering wheel angle signal S21-1 and the vehicle speed signal S31-1 after low-pass filtering by the first signal processing module M609-2, and searches to obtain the ideal roll angle signal S605-1.

[0062] like Figure 8 As shown in FIG. 1 , the control block diagram shows an embodiment of the vehicle total anti-roll moment calculation module M606. The module mainly includes three submodules: a steady-state ideal total anti-roll moment calculation module M6063, an adjustable control parameter selection module M6061, and a real vehicle anti-roll moment control output module M6062. Figure 6 The connection relationship shown in is used for signal transmission, which is used for the calculation of the total anti-roll moment required for the final actual vehicle.

[0063] The submodule steady-state ideal total anti-roll moment calculation module M6063 mainly calculates the ideal total anti-roll moment based on the ideal roll angle signal S605-1, the vehicle roll arm signal S604-3 (suspension parameters calculated by module M602 and transmitted to module M604 for output), and the filtered vehicle lateral acceleration signal S41-1 using the following formula:

[0064]

[0065] Among them, M opencalis the ideal total anti-rolling moment, m is the vehicle mass, a y is the vehicle lateral acceleration signal S41-1, h is the vehicle roll arm, g is the gravity acceleration, is the ideal roll angle signal S605-1.

[0066] The submodule adjustable control parameter selection module M6061 is mainly used to consider that when the steering wheel speed and vehicle speed are different, the vehicle can select the proportional adjustment coefficient through this module, so that the vehicle has a good control effect in different steady-state scenarios. This module establishes a three-dimensional relationship between the steering wheel speed S51-1, the vehicle speed S31-1 and the proportional control parameter S6061, and can subsequently be matched and calibrated according to the open type. In this way, the proportional adjustment coefficient can be obtained through a three-dimensional table lookup.

[0067] like Fig. 9 As shown, the control block diagram shows an embodiment of the real vehicle anti-roll moment control output module M6062. This submodule performs closed-loop control based on the difference between the ideal roll angle S605-1 and the estimated vehicle steady-state body roll angle S604-1 relative to the ground, and outputs the required anti-roll moment through the following formula:

[0068]

[0069]

[0070] Among them, M need is the signal S606-1 output by closed-loop control, M last is the total anti-roll moment S604-2 acting on the vehicle at the last moment, K d is the D gain value obtained by looking up the table according to the difference between the ideal roll angle S605-1 and the estimated steady-state body roll angle S604-1 of the vehicle relative to the ground, step length is the sampling step length, Kp is the adjustable proportional coefficient S6061, To estimate the vehicle body roll angle relative to the ground in real time, err up is the upper limit of the anti-roll moment tolerance, err lower is the lower limit of the anti-roll moment tolerance (consider this factor to be different), and M is the total vehicle anti-roll moment S606 that is finally output after passing through the ideal anti-roll moment tolerance limit.

[0071] like Fig.10As shown, the control block diagram shows an embodiment of the front and rear anti-roll moment distribution coefficient calculation module M607. The module first establishes a three-dimensional relationship between the steering wheel angle signal S21-1 and the vehicle speed signal S31-1 and the ideal yaw rate signal S607-1. The actual yaw rate S61-1 of the vehicle after filtering is calculated to be different from the ideal yaw rate S607-1, and the gain value S607-2 is obtained by looking up the table, and the gain value S607-2 is added to the front and rear anti-roll moment distribution coefficient of the previous moment to obtain the front and rear anti-roll moment distribution coefficient S607-3 of the current moment, and the dynamic limit processing is performed to obtain the final front and rear anti-roll moment distribution coefficient S607.

[0072] Finally, the front and rear stabilizer bar required torque calculation module M608 obtains the vehicle total anti-roll moment S606 output by the vehicle total anti-roll moment calculation module M606 and the front and rear anti-roll moment distribution coefficient S607 output by the front and rear anti-roll moment distribution coefficient calculation module M607, such as Figure 5 As shown, the front and rear axle anti-roll moments are calculated by top-down decomposition, and the front and rear axle anti-roll moments are decomposed into the anti-roll moments contributed by the suspension and the anti-roll moments contributed by the stabilizer bar. Then, by the previous formula (3), the stabilizer bar required torque signals S18 and S28 are calculated from the front and rear anti-roll moments contributed by the stabilizer bar and sent to the front and rear stabilizer bar motors respectively.

[0073] The above examples comprehensively demonstrate the vehicle body steady-state control technology based on vehicle performance calibration. The vehicle performance requirements of different scenarios in steady state are realized through the active stabilizer bar application layer algorithm, the vehicle anti-roll moment is controlled, and the anti-roll moment distribution of the front and rear axles is completed, and finally the stabilizer bar torque signal requirements are calculated. The vehicle steady-state body roll is controlled by the active stabilizer bar to improve the vehicle's cornering performance. The active stabilizer bar allows the driver to select driving modes in different driving scenarios. After entering different modes, the active stabilizer bar adjusts the stabilizer bar torque through the control method to control the vehicle performance. When cornering in steady state, ensure that the vehicle drives according to the roll angle required by the user, so as to provide the best user experience; when changing lines transiently, ensure that the vehicle drives according to the yaw rate and roll rate required by the user; when on a damaged road, comprehensively evaluate the driving conditions to ensure that the handling stability and comfort performance meet the user's needs.

[0074] Although the present invention is described in detail in conjunction with a limited number of examples, it should be readily understood that the present invention is not limited to these disclosed embodiments. On the contrary, the present invention can be modified to combine any number of variations, changes, substitutions or equivalent methods not described before, but it is suitable with the spirit and scope of the present invention. In addition, although multiple embodiments of the present invention are described, it should be understood that many aspects of the present invention can only include some of the described embodiments. In addition, the present invention should not be considered as being subject to the limitation described above.

Claims

1. A vehicle roll angle estimation method, characterized in that: include: Step 1, signal processing: collecting the vehicle height signal and the torque signal returned by the active stabilizer bar, and filtering them; Step 2, estimating the roll angle at the wheel center: using the vehicle height signal and the vehicle size parameter wheelbase to calculate the roll angle generated by the suspension, that is, the roll angle at the wheel center; Step 3, suspension parameter calculation: Calculate suspension component parameters to system-level parameters based on vehicle mass parameters, vehicle size parameters, elastic component parameters, and hard point related parameters, including suspension stiffness, suspension roll stiffness, tire contribution roll stiffness, and vehicle roll arm; Step 4, back calculation of the roll moment contributed by the stabilizer bar in real time: the anti-roll moment of the front and rear axles contributed by the stabilizer bar is back calculated based on the torque provided by the active stabilizer bar in real time; Step 5, estimating the steady-state body roll angle of the vehicle relative to the ground: the total body roll angle relative to the ground is obtained by the sum of the roll angle at the wheel center and the tire contribution roll angle; the tire contribution roll angle is the front and rear axle anti-roll moment divided by the tire roll stiffness; the front and rear axle anti-roll moment is the sum of the front and rear axle anti-roll moment contributed by the stabilizer bar and the suspension contribution anti-roll moment; the suspension contribution anti-roll moment is the product of the suspension roll stiffness and the roll angle at the wheel center.

2. The vehicle roll angle estimation method according to claim 1, characterized in that: The estimation of the roll angle at the wheel center includes: The roll angle at the front wheel center is calculated by the following formula: in, is the roll angle at the front axle wheel center, H Lfwc is the front left wheel center compression, H Rfwc is the front right wheel center compression, T fw Front track width set externally by vehicle dimensions; Rear wheel center tilt angle The same principle as the front wheel center roll angle is used to calculate the roll angle. Finally, the average of the front and rear wheel center roll angles is taken to get the body wheel center roll angle.

3. The vehicle roll angle estimation method according to claim 1, characterized in that: The anti-roll moment of the front and rear axles contributed by the stabilizer bar is calculated by the following formula: Among them, M ARB The anti-roll moment of the front and rear axles contributed by the stabilizer bar; T ARB The feedback torque of the front and rear stabilizer bar motors; T w is the vehicle wheelbase; l ARB_arm is the stabilizer lever arm; i ARB is the stabilizer bar wheel center leverage ratio.

4. The vehicle roll angle estimation method according to claim 1, characterized in that: The vehicle mass parameters include vehicle mass, front and rear axle loads, and vehicle center of mass height parameters; vehicle size parameters include front and rear track and wheelbase parameters; elastic component parameters include spring stiffness, bushing parasitic stiffness, buffer block stiffness, tire radial stiffness, and stabilizer bar bushing stiffness parameters; hard point related parameters include spring lever ratio, stabilizer bar lever ratio, stabilizer bar knuckle arm length, and front axle roll center height parameters.

5. The vehicle roll angle estimation method according to claim 1, characterized in that: In estimating the steady-state body roll angle of the vehicle relative to the ground, the tire equivalent coefficient is added for calibration, and the front and rear are considered separately, taking the average of the front and rear roll angles.

6. A vehicle roll angle estimation system, implementing the vehicle roll angle estimation method according to any one of claims 1 to 5, characterized in that: It includes a signal processing module, a suspension parameter calculation module, a wheel center roll angle estimation module, a stabilizer bar real-time contribution roll moment back calculation module, and a vehicle relative to the ground steady-state body roll angle estimation module. The above modules are used to calculate the vehicle relative to the ground steady-state body roll angle in real time for the steady-state body roll angle control strategy implementation; The signal processing module is used to collect the vehicle height signal and the torque signal returned by the active stabilizer bar, and perform filtering processing; The wheel center roll angle estimation module calculates the roll angle generated by the suspension, i.e., the wheel center roll angle, by using the vehicle height signal and the vehicle size parameter wheelbase; The suspension parameter calculation module is used to calculate the suspension component parameters to system-level parameters according to the vehicle mass parameters, vehicle size parameters, elastic element parameters, and hard point related parameters, including suspension stiffness, suspension roll stiffness, tire contribution roll stiffness, and vehicle roll arm; The stabilizer bar real-time contribution roll moment back-calculation module is used to back-calculate the front and rear axle anti-roll moment contributed by the stabilizer bar based on the torque provided by the active stabilizer bar in real time; The vehicle-to-ground steady-state body roll angle estimation module is used to estimate the total vehicle-to-ground steady-state body roll angle, that is, to obtain the vehicle roll angle; the total body roll angle relative to the ground is obtained by the sum of the wheel center roll angle and the tire contribution roll angle; The tire-contributed roll angle is the front and rear axle anti-roll moment divided by the tire roll stiffness. The front and rear axle anti-roll moment is the sum of the front and rear axle anti-roll moment contributed by the stabilizer bar and the suspension-contributed anti-roll moment. The suspension-contributed anti-roll moment is the product of the suspension roll stiffness and the roll angle at the wheel center.

7. An electronic device, characterized in that: include: one or more processors; A storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, enables the electronic device to implement the vehicle roll angle estimation method according to any one of claims 1 to 5.

8. A vehicle, characterized in that: The vehicle is equipped with the electronic device according to claim 7.

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