A horizontal wheel stiffness control method, device, equipment and storage medium

Abstract

The application discloses a horizontal wheel stiffness control method, device, equipment and storage medium, and is applied to the field of train control, and the method comprises the steps of establishing a force analysis model of a straddle-type monorail vehicle, determining a target guiding torque, inputting the target guiding torque into the force analysis model to obtain a tire radial force, obtaining a tire radial compression amount under the target guiding torque, determining a horizontal wheel target stiffness based on horizontal wheel radial force in the tire radial force and horizontal wheel radial compression amount in the tire radial compression amount, determining a stiffness-tire pressure correlation model, inputting the horizontal wheel target stiffness into the stiffness-tire pressure correlation model to obtain a horizontal wheel target tire pressure, and adjusting the tire pressure of the horizontal wheel to the horizontal wheel target tire pressure, so that the stiffness of the horizontal wheel reaches the horizontal wheel target stiffness. According to the method, the stiffness control of the horizontal wheel is realized through the tire pressure adjustment of the horizontal wheel, so that the straddle-type monorail vehicle has better anti-overturning capability when passing through a curve.

Description

Technical Field

[0001] This invention relates to the field of train control, and in particular to a method, apparatus, device, and computer-readable storage medium for controlling the stiffness of horizontal wheels. Background Technology

[0002] Straddle-type monorail vehicles have a very small lateral wheel spacing, relying on the contact between the horizontal wheels and the track side to ensure the vehicle's anti-tipping ability. If the radial force of the horizontal wheels is zero, the vehicle's anti-tipping ability is insufficient when traversing curved tracks, potentially leading to the vehicle derailing and causing a major safety accident. Increasing the preload of the horizontal wheels enhances the vehicle's anti-roll capability and improves its curve-traversing performance, but it also directly increases the wear on the running wheels and horizontal tire surfaces, affecting the service life of the rubber tires. Furthermore, excessive vehicle speed results in excessive centrifugal force and a larger tilt angle, causing the lateral displacement of the horizontal wheels to exceed their preload, at which point the horizontal wheels may derail. Therefore, it is necessary to actively adjust the stiffness of the horizontal wheels to achieve better overturning stability. Summary of the Invention

[0003] The purpose of this invention is to provide a method, device, equipment, and computer-readable storage medium for controlling the stiffness of horizontal wheels, which can be applied to the field of train control. This method achieves stiffness control of horizontal wheels by adjusting the tire pressure of the horizontal wheels, so that straddle-type monorail vehicles have better anti-overturning ability when passing through curves.

[0004] To solve the above-mentioned technical problems, the present invention provides a method for controlling the stiffness of a horizontal wheel, comprising:

[0005] A force analysis model for a straddle-type monorail vehicle is established, the target guiding torque is determined, and the target guiding torque is input into the force analysis model to obtain the tire radial force.

[0006] Obtain the tire radial compression under the target guiding torque, and determine the target stiffness of the horizontal wheel based on the horizontal wheel radial force in the tire radial force and the horizontal wheel radial compression in the tire radial compression.

[0007] Determine the stiffness-tire pressure correlation model, and input the target stiffness of the horizontal wheel into the stiffness-tire pressure correlation model to obtain the target tire pressure of the horizontal wheel;

[0008] Adjust the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel so that the stiffness of the horizontal wheel reaches the target stiffness of the horizontal wheel.

[0009] Optionally, the method further includes:

[0010] Obtain the running wheel speed and determine the vehicle slip ratio based on the running wheel speed;

[0011] If the slip ratio is greater than the slip ratio threshold, then a target tire pressure for the running wheel that is lower than the current tire pressure of the running wheel is determined.

[0012] The target tire pressure of the running wheels is sent to the tire pressure regulation system so that the tire pressure regulation system adjusts the tire pressure of the running wheels to the target tire pressure of the running wheels;

[0013] The friction coefficient of the running wheel is determined based on the target tire pressure of the running wheel, and the adhesive torque of the running wheel is determined based on the friction coefficient of the running wheel, the radial force of the running wheel in the radial force of the tire, and the tire radius of the running wheel.

[0014] A torque command is sent to the motor controller of the running wheel to control the driving torque of the running wheel to be less than the adhesive torque of the running wheel.

[0015] Optionally, the method further includes:

[0016] The tire measured radial force is determined based on the tire compression, and the equivalent radial force is determined based on the tire measured radial force.

[0017] The radial force threshold is determined based on the maximum radial force of the guide wheel, the maximum radial force of the stabilizing wheel, and the maximum radial force of the running wheel.

[0018] If the equivalent radial force is greater than the radial force threshold, the target guiding torque is redefined.

[0019] Optionally, the method further includes:

[0020] A correlation model of horizontal wheel radial force, vehicle speed, and curve radius is established. The vehicle speed and curve radius are input into the correlation model to obtain the reference horizontal wheel radial force output by the model.

[0021] If the radial force of the horizontal wheel is not equal to the radial force of the reference horizontal wheel, the target guiding torque is re-determined;

[0022] The expression for the correlation model of horizontal wheel radial force, vehicle speed, and curve radius is as follows:

[0023] F jz-i =μ i1 +μ i2 *v 2 +μ i3 *R;

[0024] In the formula, F jz-i Let μ be the radial force of the reference horizontal wheel for the i-th horizontal wheel. i1 μ i2 and μ i3 Let v be the constant coefficient of the i-th horizontal wheel, v be the vehicle speed, and R be the curve radius.

[0025] Optionally, the method further includes:

[0026] Establish a bogie offset angle constraint model. If the bogie offset angle does not meet the bogie offset angle constraint model, then redetermine the target guiding moment.

[0027] The expression for the bogie offset angle constraint model is:

[0028]

[0029] In the formula, θ is the bogie offset angle. Let t be the vehicle's angular acceleration, and t be the vehicle's travel time when passing through the curve.

[0030] Optionally, the method further includes:

[0031] Establish a guiding moment constraint model and determine the root mean square of the guiding moment when the curve passes through. If the root mean square of the guiding moment does not satisfy the guiding moment constraint model, then redetermine the target guiding moment.

[0032] The expression for the guiding moment constraint model is:

[0033]

[0034] In the formula, M rms M is the root mean square of the guiding torque. max For the maximum guiding torque, I z Let A be the moment of inertia, R be the longitudinal distance between the guide wheels, R be the curve radius, and v be the vehicle speed.

[0035] Optionally, adjusting the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel includes:

[0036] The target tire pressure of the horizontal wheel is sent to the tire pressure regulation system so that the tire pressure regulation system adjusts the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel.

[0037] To solve the above-mentioned technical problems, the present invention provides a horizontal wheel stiffness control device, comprising:

[0038] The first module is used to establish a force analysis model for straddle-type monorail vehicles, determine the target guiding torque, input the target guiding torque into the force analysis model, and obtain the tire radial force.

[0039] The second module is used to obtain the tire radial compression under the target guiding torque, and to determine the target stiffness of the horizontal wheel based on the horizontal wheel radial force in the tire radial force and the horizontal wheel radial compression in the tire radial compression.

[0040] The third module is used to determine the stiffness-tire pressure correlation model, and inputs the target stiffness of the horizontal wheel into the stiffness-tire pressure correlation model to obtain the target tire pressure of the horizontal wheel;

[0041] The fourth module is used to adjust the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel so that the stiffness of the running wheel reaches the target stiffness of the horizontal wheel.

[0042] To solve the above-mentioned technical problems, the present invention provides a horizontal wheel stiffness control device, comprising:

[0043] Memory, used to store computer programs;

[0044] A processor is used to implement the horizontal wheel stiffness control method described above when executing the computer program.

[0045] To address the aforementioned technical problems, the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the aforementioned horizontal wheel stiffness control method.

[0046] As can be seen, the method of this invention establishes a force analysis model of the straddle-type monorail vehicle, determines the target guiding torque, inputs the target guiding torque into the force analysis model to obtain the tire radial force, obtains the tire radial compression under the target guiding torque, determines the target stiffness of the horizontal wheel based on the horizontal wheel radial force in the tire radial force and the horizontal wheel radial compression in the tire radial compression, determines the stiffness-tire pressure correlation model, inputs the target stiffness of the horizontal wheel into the stiffness-tire pressure correlation model to obtain the target tire pressure of the horizontal wheel, and adjusts the tire pressure of the horizontal wheel to the target tire pressure so that the stiffness of the running wheel reaches the target stiffness of the horizontal wheel. This method of the present invention achieves stiffness control of the horizontal wheel through tire pressure adjustment, thereby enabling the straddle-type monorail vehicle to have better anti-overturning ability when passing through curves. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0048] Figure 1 A flowchart of a horizontal wheel stiffness control method provided in an embodiment of the present invention;

[0049] Figure 2 An example diagram of a bogie provided in an embodiment of the present invention;

[0050] Figure 3 This is a schematic cross-sectional view of a horizontal wheel provided in an embodiment of the present invention;

[0051] Figure 4 This is a structural block diagram of a horizontal wheel stiffness control device provided in an embodiment of the present invention.

[0052] The annotations in the attached figures are explained as follows:

[0053] 1-Front bogie; 2-Rear bogie; 3-Intake valve; 4-Ventilation hole; 5-Exhaust valve; 6-Air reservoir; 7-Sealing ring; 8-Horizontal wheel tire; 9-Main shaft; 10-Wheel rim; 11-Tire inner cavity; 12-Explosion-proof support body; 13-Explosion-proof valve. Detailed Implementation

[0054] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] Straddle-type monorail vehicles have a very small lateral wheel spacing, relying on the contact between guide wheels and stabilizing wheels and the track side to ensure the vehicle's anti-overturning capability. If the radial force on the horizontal wheels is zero, the vehicle's anti-overturning capability is insufficient when traversing curves, potentially leading to the vehicle derailing from the track beam and causing a major safety accident. Increasing the preload on the horizontal wheels enhances the vehicle's anti-roll capability and improves its curve-passing performance. However, this directly increases the wear on the running wheels and the horizontal tire surface, affecting the service life of the rubber tires.

[0056] Secondly, if the vehicle's speed is too high, it will experience excessive centrifugal force, resulting in a larger tilt angle. The lateral displacement of the horizontal wheels will exceed their pre-compression, causing them to detach from the rail surface. Therefore, it is necessary to actively adjust the stiffness of the horizontal wheels to achieve better overturning stability.

[0057] Straddle-type monorail lines have a small bending radius, and the excitation spectrum of the track beam is larger than that of the railway. Therefore, they are prone to impact excitation, which can lead to excessive yielding of the bogie structural components, causing damage or even failure. Simultaneously, the wheels exert a strong impact force on the beam surface, resulting in damage. Furthermore, monorail vehicles frequently slip in icy or snowy weather. Adjusting the tire pressure of the running wheels to increase the contact area and improve traction can effectively prevent slippage. Other anti-skid measures, such as tire chains, can easily damage the beam surface or finger plates.

[0058] The following combination Figure 1 , Figure 1A flowchart of a horizontal wheel stiffness control method provided in an embodiment of the present invention is shown. The method may include:

[0059] S101: Establish a force analysis model for straddle-type monorail vehicles, determine the target guiding torque, input the target guiding torque into the force analysis model, and obtain the tire radial force.

[0060] According to existing research, the evaluation indicators for vehicle curve passability mainly include horizontal wheel radial force, overturning coefficient, tire force scalar and guiding torque. Taking guiding torque as an example, when a vehicle is subjected to a large unbalanced centrifugal acceleration, a force analysis model can be established for straddle-type monorail vehicles.

[0061] The expression of the force analysis model in this embodiment is related to the number of horizontal wheels (guide wheels and stabilizing wheels) and running wheels of the straddle-type monorail vehicle. In practical applications, the force analysis model can be determined based on the number of various types of tires of the straddle-type monorail vehicle. In the example, each straddle-type monorail vehicle can have four guide wheels, two stabilizing wheels, and four running wheels. Therefore, the force analysis model of the straddle-type monorail vehicle in this embodiment can be:

[0062]

[0063] In the formula, F i For the horizontal wheel radial force, i is taken as 1-6. F1, F2, F3, and F4 are the radial forces of the front left, front right, rear right, and rear left guide wheels, respectively. F5 and F6 are the radial forces of the left and right stabilizing wheels, respectively. m is the vehicle mass, g is the acceleration due to gravity, α is the superelevation angle of the track beam, β is the roll angle of the car body, v is the vehicle speed, R is the curve radius, and g c For centrifugal acceleration, F7 and F8 are the longitudinal forces of the second suspension springs, A is the longitudinal spacing of the guide wheels, B is the lateral spacing of the second suspension springs, C is the wheelbase, N is the distance from the tire contact centerline to the center of the track beam, M is the guiding torque on the bogie, and F9 and F... 9c F is the lateral force on the two coaxial traveling wheels on the first axle. 10 and F 10c F is the lateral force on the coaxial running wheel on the second axle. 11 and F 11c F is the lateral force on the two running wheels on the same side of the bogie. 12 and F 12c This refers to the lateral force on the two running wheels on the other side of the bogie.

[0064] Since the lateral force of the running wheel is positively correlated with the radial force of the running wheel, this embodiment can determine the positive correlation coefficient of the lateral force of each running wheel. The lateral force of the running wheel obtained by the force analysis model is multiplied with the corresponding positive correlation coefficient to obtain the corresponding radial force of the running wheel.

[0065] This embodiment can determine the target guiding torque, input the target guiding torque into the force analysis model, and obtain the tire radial force.

[0066] S102: Obtain the tire radial compression under the target guiding torque, and determine the target stiffness of the horizontal wheel based on the horizontal wheel radial force in the tire radial force and the horizontal wheel radial compression in the tire radial compression.

[0067] S103: Determine the stiffness-tire pressure correlation model, input the target stiffness of the horizontal wheel into the stiffness-tire pressure correlation model to obtain the target tire pressure of the horizontal wheel.

[0068] Since the magnitude of the radial force (load force) of a tire is determined by the tire pressure, this embodiment can establish the relationship between tire pressure, tire radial force, tire compression, and tire stiffness, as shown below:

[0069] (PP a )v λ =cons;

[0070] F = (PP) a S = Kx;

[0071] Furthermore, by differentiating the tire compression, we can obtain the expression for the stiffness-tire pressure correlation model:

[0072]

[0073] In the formula, P is the tire pressure, P a Where is atmospheric pressure, v is vehicle speed, λ is polytropic index, F is tire radial force, K is tire stiffness, x is tire radial compression, S is tire internal volume, cons is a constant, and Z is effective load area.

[0074] In the rate of change of effective load area, the effective load area has a linear relationship with the tire compression:

[0075]

[0076] In the formula, Z is the effective load area, Z0 is the initial effective load area, Q is the linear coefficient, and x is the tire radial compression.

[0077] Furthermore, the expression for the stiffness-tire pressure correlation model can be rewritten as:

[0078]

[0079] The expression for the radial force of a tire can be:

[0080]

[0081] In this embodiment, the radial compression of the tire under the target guiding torque can be obtained. The target stiffness of the horizontal wheel is determined based on the radial force of the horizontal wheel in the radial force of the tire and the radial compression of the horizontal wheel in the radial compression of the tire. This embodiment does not limit the method of obtaining the radial compression of the tire. It can generally be obtained by sensor collection and conversion.

[0082] In this embodiment, the horizontal wheel radial force in the tire radial force and the horizontal wheel radial compression in the tire radial compression can be substituted into the above formula to obtain the target stiffness of the horizontal wheel that needs to be adjusted under the target guiding torque. The target tire pressure of the horizontal wheel can be obtained by inputting the target stiffness of the horizontal wheel into the stiffness-tire pressure correlation model after it is determined.

[0083] S104: Adjust the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel so that the stiffness of the running wheel reaches the target stiffness of the horizontal wheel.

[0084] This embodiment can adjust the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel so that the stiffness of the running wheel reaches the target stiffness of the horizontal wheel. This embodiment does not limit the specific method of tire pressure adjustment. Generally, the target tire pressure of the horizontal wheel can be sent to the tire pressure adjustment system so that the tire pressure adjustment system can adjust the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel. In this embodiment, the tire pressure adjustment system can be connected to each tire of the straddle-type monorail vehicle to control tire inflation and deflation.

[0085] In this embodiment, in order to ensure the anti-overturning capability of the straddle-type monorail vehicle, multiple constraints can be set during the horizontal force stiffness control process. Each constraint can be set individually or in combination.

[0086] First, this embodiment can set constraints to constrain the radial force of each tire, so as to avoid the radial force of the tire exceeding the bearing range under the target guiding torque. This embodiment does not limit the specific method of constraining the radial force of the tire. Generally, the tire measured radial force can be determined based on the tire compression, and the equivalent radial force can be determined based on the tire theoretical radial force. The radial force threshold can be determined based on the maximum radial force of the guide wheel, the maximum radial force of the stabilizing wheel, and the maximum radial force of the running wheel. If the equivalent radial force is greater than the radial force threshold, the target guiding torque is re-determined.

[0087] This embodiment can determine the tire radial force based on the tire compression. The tire radial force mentioned in this embodiment is the theoretical force determined by the force analysis model. The tire radial force is the tire radial force calculated by converting the collected tire compression. The specific conversion process can be performed by substituting the relationship between tire pressure, tire radial force, tire compression and tire stiffness.

[0088] This embodiment can determine the equivalent radial force based on the theoretical radial force of the tire. In this embodiment, the equivalent radial force is the combined equivalent radial force after measuring the radial forces of each tire. Generally, the expression for the equivalent radial force can be:

[0089] F all =F w +F d +2F z ;

[0090] In the formula, F all For the equivalent radial force, i.e. the equivalent wear force, F w To measure the total radial force of the stabilizing wheel, F d The guide wheel measures the total radial force, F z The total radial force is measured on the running wheels.

[0091] This embodiment can limit the equivalent radial force to be less than or equal to the radial force threshold, as shown in the following formula:

[0092] F all ≤F wmax +F dmax +2F zmax ;

[0093] In the formula, F wmax To stabilize the maximum radial force of the wheel, F dmax F is the maximum radial force of the guide wheel. zmax This represents the maximum radial force on the running wheel.

[0094] Furthermore, this embodiment can also establish a correlation model between horizontal wheel radial force, vehicle speed, and curve radius to constrain the horizontal wheel radial force. By inputting the vehicle speed and curve radius into the correlation model, the reference horizontal wheel radial force output by the model can be obtained. If the horizontal wheel radial force is not equal to the corresponding reference horizontal wheel radial force, the target guiding torque can be re-determined.

[0095] The expression for the correlation model of horizontal wheel radial force, vehicle speed, and curve radius is as follows:

[0096] F jz-i =μ i1 +μ i2 *v 2 +μi3 *R;

[0097] In the formula, F jz-i Let μ be the radial force of the reference horizontal wheel for the i-th horizontal wheel. i1 μ i2 and μ i3 Let be the constant coefficient of the i-th horizontal wheel, v be the vehicle speed, and R be the curve radius when the vehicle passes through the curve. In the example, i takes values ​​from 1 to 6.

[0098] Furthermore, this embodiment can constrain the bogie offset angle. Specifically, this embodiment can establish a bogie offset angle constraint model. If the bogie offset angle does not meet the bogie offset angle constraint model, the target guiding moment is re-determined.

[0099] The expression for the bogie offset angle constraint model is:

[0100]

[0101] In the formula, θ is the bogie offset angle. Let t be the vehicle's angular acceleration, and t be the vehicle's travel time when passing through the curve.

[0102] Finally, this embodiment can constrain the set target guiding torque. Specifically, this embodiment can establish a guiding torque constraint model to determine the root mean square of the guiding torque when the curve passes through. If the root mean square of the guiding torque does not satisfy the guiding torque constraint model, the target guiding torque is re-determined.

[0103] The expression for the guiding moment constraint model is:

[0104]

[0105] In the formula, M rms M is the root mean square of the guiding torque. max For the maximum guiding torque, I z Let A be the moment of inertia, R be the longitudinal distance between the guide wheels, R be the curve radius, and v be the vehicle speed.

[0106] according to Figure 2 As shown, in the actual application of the method of the present invention, the front bogie (1) and the rear bogie (2) are located on a curve section. In order for the vehicle to have good curve passing performance, the tire pressure of the front left and rear right guide wheels of the front bogie must be increased to increase the radial force. Meanwhile, the tire pressure of the front right and rear left guide wheels is reduced to reduce the radial force. In this way, when the vehicle turns left, the radial force on the four guide wheels of the front bogie will form a guiding torque that makes the vehicle rotate in the direction of track travel. The rear bogie turns right relative to the front bogie, so the radial force of the four guide wheels should form a guiding torque in the opposite direction to that of the front bogie.

[0107] To accommodate the tire pressure regulation system, the cross-sectional view of the horizontal wheel in this embodiment can be shown as follows: Figure 3 As shown, the intake valve 3 and exhaust valve 5 are mounted on the main shaft 9. The main shaft has an internal vent 4 leading to the air reservoir 6. The air reservoir has sealing rings 7 at the top and bottom to prevent gas leakage. The air reservoir has a through-hole that passes through the rim 10 to the inner cavity 11 of the horizontal wheel tire 8. In the event of a tire blowout, inflation to the explosion-proof support 12 enables emergency driving. Simultaneously, the explosion-proof valve 13 automatically blocks the air passage to the tire.

[0108] Furthermore, since lowering tire pressure can improve tire traction when the vehicle is traveling on ice, and considering that under the same load, lower tire pressure can increase the contact area between the tire and the ice surface, thereby increasing the coefficient of friction of the contact surface, this embodiment can improve the ice passability and anti-skid performance of the straddle-type monorail vehicle by adjusting the tire pressure of the running wheels.

[0109] Specifically, this embodiment can obtain the running wheel speed and determine the vehicle slip ratio based on the running wheel speed; if the slip ratio is greater than the slip ratio threshold, a target running wheel tire pressure lower than the current running wheel tire pressure is determined; the target running wheel tire pressure is sent to the tire pressure regulation system so that the tire pressure regulation system adjusts the running wheel tire pressure to the target running wheel tire pressure; the running wheel friction coefficient is determined based on the target running wheel tire pressure, and the running wheel adhesive torque is determined based on the running wheel friction coefficient, the running wheel radial force in the tire radial force, and the running wheel tire radius; a torque command is sent to the running wheel motor controller to control the running wheel drive torque to be less than the running wheel adhesive torque.

[0110] In this embodiment, the vehicle slip ratio can be determined by the rotational speed of the running wheels. If the vehicle slip ratio is greater than the slip ratio threshold, the tire pressure of the running wheels can be reduced to increase the coefficient of friction between the tire and the contact surface.

[0111] Factors such as tire pressure, load, and speed all affect the tire's coefficient of friction. Increased relative sliding speed between the tire and the ice surface reduces the coefficient of friction, decreasing tire-ice adhesion and limiting traction. Under heavier loads, the contact area between the tire and ice increases, resulting in a larger dry friction zone. This leads to higher traction and torque at low speeds with higher loads. Reducing tire pressure improves traction; under the same load, lower tire pressure increases the tire-ice contact area, thus increasing the coefficient of friction.

[0112] The correlation model between the running tire pressure and the friction coefficient of the running wheel can be shown in the following formula:

[0113] μ m =f(P z ,v,E);

[0114] In the formula, μ m P is the coefficient of friction of the running wheel. z Let v be the tire pressure, v be the vehicle speed, E be a factor combining the tire rubber material, aspect ratio, and tire width, and f be a correlation function.

[0115] In this embodiment, the target tire pressure of the running wheel can be substituted into the above formula to obtain the coefficient of friction of the running wheel under the target tire pressure. Furthermore, the adhesive torque of the running wheel can be determined based on the coefficient of friction of the running wheel, the radial force of the running wheel in the tire radial force, and the tire radius of the running wheel. Specifically, it can be calculated using the following formula:

[0116] N j =μ m-j F j r;

[0117] In the formula, N j Let μ be the adhesive torque of the j-th traveling wheel. m-j Let F be the coefficient of friction of the j-th traveling wheel. j The radial force of the j-th traveling wheel.

[0118] This embodiment can send torque commands to the motor controllers of the running wheels to control the driving torque of the running wheels to be less than the adhesive torque of the running wheels. Specifically, torque commands can be sent directly to the motor controllers of each running wheel via the CAN (Controller Area Network) bus, so that the motor reduces the driving torque output and the driving torque is less than the adhesive torque of each running wheel, thereby achieving the purpose of traction torque control.

[0119] Based on the above embodiments, the present invention achieves horizontal wheel stiffness control by adjusting the tire pressure of the horizontal wheels, so that the straddle-type monorail vehicle has better anti-overturning ability when passing through curves.

[0120] The following combination Figure 4 The figure shows a structural block diagram of a horizontal wheel stiffness control device provided in an embodiment of the present invention. The device may include:

[0121] The first module 100 is used to establish a force analysis model of a straddle-type monorail vehicle, determine the target guiding torque, input the target guiding torque into the force analysis model, and obtain the tire radial force.

[0122] The second module 200 is used to obtain the tire radial compression under the target guiding torque, and to determine the target stiffness of the horizontal wheel based on the horizontal wheel radial force in the tire radial force and the horizontal wheel radial compression in the tire radial compression.

[0123] The third module 300 is used to determine the stiffness-tire pressure correlation model, and inputs the target stiffness of the horizontal wheel into the stiffness-tire pressure correlation model to obtain the target tire pressure of the horizontal wheel;

[0124] The fourth module 400 is used to adjust the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel so that the stiffness of the running wheel reaches the target stiffness of the horizontal wheel.

[0125] Based on the above embodiments, the method of the present invention achieves stiffness control of the horizontal wheels by adjusting the tire pressure of the horizontal wheels, so that the straddle-type monorail vehicle has better anti-overturning ability when passing through curves.

[0126] Based on the above embodiments, the device may further include:

[0127] The fifth module is used to obtain the running wheel speed and determine the vehicle slip ratio based on the running wheel speed;

[0128] The sixth module is used to determine a target tire pressure for the running wheels that is lower than the current tire pressure of the running wheels if the slip ratio is greater than the slip ratio threshold.

[0129] The seventh module is used to send the target tire pressure of the running wheels to the tire pressure regulation system, so that the tire pressure regulation system adjusts the tire pressure of the running wheels to the target tire pressure of the running wheels;

[0130] The eighth module is used to determine the friction coefficient of the running wheel based on the target tire pressure of the running wheel, and to determine the adhesive torque of the running wheel based on the friction coefficient of the running wheel, the radial force of the running wheel in the radial force of the tire, and the tire radius of the running wheel;

[0131] The ninth module is used to send torque commands to the motor controller of the running wheel to control the driving torque of the running wheel to be less than the adhesive torque of the running wheel.

[0132] Based on the above embodiments, the device may further include:

[0133] The tenth module is used to determine the tire's measured radial force based on the tire compression, and to determine the equivalent radial force based on the tire's measured radial force.

[0134] Module 11 is used to determine the radial force threshold based on the maximum radial force of the guide wheel, the maximum radial force of the stabilizing wheel, and the maximum radial force of the running wheel;

[0135] The twelfth module is used to redetermine the target guiding torque if the equivalent radial force is greater than the radial force threshold.

[0136] Based on the above embodiments, the device may further include:

[0137] The thirteenth module is used to establish a correlation model of horizontal wheel radial force, vehicle speed, and curve radius. The vehicle speed and curve radius are input into the correlation model of horizontal wheel radial force, vehicle speed, and curve radius to obtain the reference horizontal wheel radial force output by the model.

[0138] The fourteenth module is used to redetermine the target guiding torque if the radial force of the horizontal wheel is not equal to the radial force of the reference horizontal wheel.

[0139] The expression for the correlation model of horizontal wheel radial force, vehicle speed, and curve radius is as follows:

[0140] F jz-i =μ i1 +μ i2 *v 2 +μ i3 *R;

[0141] In the formula, F jz-i Let μ be the radial force of the reference horizontal wheel for the i-th horizontal wheel. i1 μ i2 and μ i3 Let v be the constant coefficient of the i-th horizontal wheel, v be the vehicle speed, and R be the curve radius.

[0142] Based on the above embodiments, the device may further include:

[0143] The fifteenth module is used to establish a bogie offset angle constraint model. If the bogie offset angle does not meet the bogie offset angle constraint model, the target guiding moment is re-determined.

[0144] The expression for the bogie offset angle constraint model is:

[0145]

[0146] In the formula, θ is the bogie offset angle. Let t be the vehicle's angular acceleration, and t be the vehicle's travel time when passing through the curve.

[0147] Based on the above embodiments, the device may further include:

[0148] The sixteenth module is used to establish a guiding moment constraint model and determine the root mean square of the guiding moment when passing through the curve. If the root mean square of the guiding moment does not satisfy the guiding moment constraint model, the target guiding moment is re-determined.

[0149] The expression for the guiding moment constraint model is:

[0150]

[0151] In the formula, Mrms M is the root mean square of the guiding torque. max For the maximum guiding torque, I z Let A be the moment of inertia, R be the longitudinal distance between the guide wheels, R be the curve radius, and v be the vehicle speed.

[0152] Based on the above embodiments, the fourth module 400 may include:

[0153] The first unit is used to send the target tire pressure of the horizontal wheel to the tire pressure regulation system so that the tire pressure regulation system adjusts the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel.

[0154] Based on the above embodiments, the present invention also provides a horizontal wheel stiffness control device. This device may include a memory and a processor. The memory stores a computer program, and when the processor calls the computer program in the memory, it can implement the steps provided in the above embodiments. Of course, the device may also include various necessary network interfaces, power supplies, and other components.

[0155] The present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by an execution terminal or processor, can implement the method provided in the embodiments of the present invention; the storage medium may include various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0156] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A method for controlling the stiffness of a horizontal wheel, characterized in that, include: A force analysis model for a straddle-type monorail vehicle is established, the target guiding torque is determined, and the target guiding torque is input into the force analysis model to obtain the tire radial force. Obtain the tire radial compression under the target guiding torque, and determine the target stiffness of the horizontal wheel based on the horizontal wheel radial force in the tire radial force and the horizontal wheel radial compression in the tire radial compression. Determine the stiffness-tire pressure correlation model, and input the target stiffness of the horizontal wheel into the stiffness-tire pressure correlation model to obtain the target tire pressure of the horizontal wheel; Adjust the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel so that the stiffness of the horizontal wheel reaches the target stiffness of the horizontal wheel.

2. The horizontal wheel stiffness control method according to claim 1, characterized in that, Also includes: Obtain the running wheel speed and determine the vehicle slip ratio based on the running wheel speed; If the slip ratio is greater than the slip ratio threshold, then a target tire pressure for the running wheel that is lower than the current tire pressure of the running wheel is determined. The target tire pressure of the running wheels is sent to the tire pressure regulation system so that the tire pressure regulation system adjusts the tire pressure of the running wheels to the target tire pressure of the running wheels; The friction coefficient of the running wheel is determined based on the target tire pressure of the running wheel, and the adhesive torque of the running wheel is determined based on the friction coefficient of the running wheel, the radial force of the running wheel in the radial force of the tire, and the tire radius of the running wheel. A torque command is sent to the motor controller of the running wheel to control the driving torque of the running wheel to be less than the adhesive torque of the running wheel.

3. The horizontal wheel stiffness control method according to claim 1, characterized in that, Also includes: The tire radial force is determined based on the tire radial compression, and the equivalent radial force is determined based on the tire radial force. The radial force threshold is determined based on the maximum radial force of the guide wheel, the maximum radial force of the stabilizing wheel, and the maximum radial force of the running wheel. If the equivalent radial force is greater than the radial force threshold, the target guiding torque is redefined.

4. The horizontal wheel stiffness control method according to claim 1, characterized in that, Also includes: A correlation model of horizontal wheel radial force, vehicle speed, and curve radius is established. The vehicle speed and curve radius are input into the correlation model to obtain the reference horizontal wheel radial force output by the model. If the radial force of the horizontal wheel is not equal to the radial force of the reference horizontal wheel, the target guiding torque is re-determined; The expression for the correlation model of horizontal wheel radial force, vehicle speed, and curve radius is as follows: F jz-i =μ i1 +m i2 *v 2 +m i3 *R; In the formula, F jz-i Let μ be the radial force of the reference horizontal wheel for the i-th horizontal wheel. i1 μ i2 and μ i3 Let v be the constant coefficient of the i-th horizontal wheel, v be the vehicle speed, and R be the curve radius.

5. The horizontal wheel stiffness control method according to claim 1, characterized in that, Also includes: Establish a bogie offset angle constraint model. If the bogie offset angle does not meet the bogie offset angle constraint model, then redetermine the target guiding moment. The expression for the bogie offset angle constraint model is: In the formula, θ is the bogie offset angle. Let t be the vehicle's angular acceleration, and t be the vehicle's travel time when passing through the curve.

6. The horizontal wheel stiffness control method according to claim 1, characterized in that, Also includes: Establish a guiding moment constraint model and determine the root mean square of the guiding moment when the curve passes through. If the root mean square of the guiding moment does not satisfy the guiding moment constraint model, then redetermine the target guiding moment. The expression for the guiding moment constraint model is: In the formula, M rms M is the root mean square of the guiding torque. max For the maximum guiding torque, I z Let A be the moment of inertia, R be the longitudinal distance between the guide wheels, R be the curve radius, and v be the vehicle speed.

7. The horizontal wheel stiffness control method according to claim 1, characterized in that, Adjusting the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel includes: The target tire pressure of the horizontal wheel is sent to the tire pressure regulation system so that the tire pressure regulation system adjusts the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel.

8. A horizontal wheel stiffness control device, characterized in that, include: The first module is used to establish a force analysis model for straddle-type monorail vehicles, determine the target guiding torque, input the target guiding torque into the force analysis model, and obtain the tire radial force. The second module is used to obtain the tire radial compression under the target guiding torque, and to determine the target stiffness of the horizontal wheel based on the horizontal wheel radial force in the tire radial force and the horizontal wheel radial compression in the tire radial compression. The third module is used to determine the stiffness-tire pressure correlation model, and inputs the target stiffness of the horizontal wheel into the stiffness-tire pressure correlation model to obtain the target tire pressure of the horizontal wheel; The fourth module is used to adjust the tire pressure of the horizontal wheel to the target tire pressure of the horizontal wheel so that the stiffness of the horizontal wheel reaches the target stiffness of the horizontal wheel.

9. A horizontal wheel stiffness control device, characterized in that, include: Memory, used to store computer programs; A processor for executing the computer program to implement the horizontal wheel stiffness control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, implement the horizontal wheel stiffness control method as described in any one of claims 1 to 7.

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