A control method of a transmission countershaft brake, a vehicle, and a storage medium

Abstract

The application discloses a control method of a transmission intermediate shaft brake, a vehicle and a storage medium. The method comprises the following steps: starting the intermediate shaft brake; acquiring a target rotating speed difference estimation value at a brake starting moment, and a first brake basic characteristic parameter array; acquiring a stable brake demand rotating speed difference array, a theoretical stable brake demand time array and a theoretical total demand brake time; determining a total demand brake target time under different upshift types; acquiring a difference value between the total demand brake target time and the theoretical total demand brake time, selecting a theoretical total demand brake time corresponding to a minimum difference value, and determining an actual opening valve time of an intake valve of the intermediate shaft brake according to the theoretical total demand brake time. The actual opening valve time of the intake valve of the intermediate shaft brake is confirmed, so that accurate control of the intermediate shaft brake is ensured, and the smoothness and speed of a gear shifting process are improved.

Description

A control method for a transmission intermediate shaft brake, a vehicle, and a storage medium. Technical Field

[0001] This invention relates to the field of automatic transmission control technology, and in particular to a control method for a transmission intermediate shaft brake, a vehicle, and a storage medium. Background Technology

[0002] The existing AMT automatic transmission is developed from the MT manual transmission by adding various sensors, transmission control unit, electronically controlled shift actuator, and clutch actuator. Compared with other automatic transmission solutions, it has the advantages of low cost and high transmission efficiency. During the upshifting process of the automatic transmission, the brake is used to brake the intermediate shaft, so that the speed of the target gear gear is quickly synchronized with the main shaft, shortening the shift waiting time.

[0003] With the increasing popularity of AMT transmissions, drivers' demands for vehicle comfort are also gradually increasing. This leads to increasingly higher requirements for the control of the intermediate shaft brake during gear shifting. The control of the intermediate shaft brake is mainly achieved by obtaining the difference between the speed of the current target gear and the speed of the transmission main shaft, and combining this with the current driving conditions to determine the valve opening time and the timing for starting the exhaust. If the valve opening time and the timing for starting the exhaust are not accurately controlled, it may result in insufficient braking capacity, a slow decrease in the target gear speed leading to a long shift time, or it may lead to over-braking, where the target gear speed decreases too quickly, resulting in shift shock and shift noise, seriously affecting driving comfort. Summary of the Invention

[0004] This invention provides a control method, vehicle, and storage medium for a transmission intermediate shaft brake, improving the precise control of the intermediate shaft brake and ensuring smoothness and speed during gear shifting.

[0005] According to one aspect of the present invention, a control method for a transmission intermediate shaft brake is provided, characterized in that it includes:

[0006] Engage the intermediate shaft brake;

[0007] Obtain the estimated value of the target speed difference at the moment braking begins;

[0008] Obtain the array of basic characteristic parameters of the first brake;

[0009] The stable braking demand speed difference array is obtained based on the target speed difference estimate at the braking start time and the first brake basic characteristic parameter array.

[0010] The theoretical stable braking time array is obtained based on the stable braking demand speed difference array and the first brake basic characteristic parameter array.

[0011] The theoretical total braking time is obtained based on the first brake basic characteristic parameter array and the theoretical stable braking demand time array.

[0012] Determine the total required braking target time under different upshift types;

[0013] Obtain the difference between the total required braking target time and the theoretical total required braking time, select the theoretical total required braking time corresponding to the smallest difference, and determine the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total required braking time.

[0014] Optionally, obtaining the target speed difference estimate at the moment of braking initiation includes:

[0015] Obtain the target intermediate shaft speed at the target gear;

[0016] Get the intermediate shaft speed at the moment braking begins in the current gear;

[0017] The estimated value of the difference between the target intermediate shaft speed at the start of braking is determined based on the target intermediate shaft speed in the target gear and the intermediate shaft speed at the start of braking in the current gear.

[0018] Optionally, obtaining the array of basic characteristic parameters of the first brake includes:

[0019] Get the current main air chamber pressure of the transmission valve block and the current transmission oil temperature;

[0020] Get the array of set intake valve opening times;

[0021] The main air chamber pressure of the current transmission valve block and the first brake basic characteristic parameter array at the current transmission oil temperature are determined based on the set intake valve opening time array.

[0022] Optionally, the stable braking demand speed difference array is obtained based on the estimated target speed difference at the braking start time and the first brake's basic characteristic parameter array, including:

[0023] Based on the first brake's basic characteristic parameter array, obtain the air pressure value array, torque build-up time array, and torque release time array corresponding to the valve opening time;

[0024] The maximum deceleration slope array of the intermediate shaft is obtained based on the air pressure data;

[0025] The intermediate deceleration array during torque building is obtained based on the array of maximum deceleration slope of the intermediate shaft and the array of torque building time.

[0026] The intermediate speed reduction array during torque unloading is determined based on the array of maximum speed reduction slope of the intermediate shaft and the array of torque unloading time.

[0027] Obtain the intermediate shaft speed difference, the free descent speed difference in the torque build-up response range, and the free descent speed difference in the torque unload response range;

[0028] The stable braking demand speed difference array is obtained based on the target speed difference estimate at the braking start time, the intermediate shaft speed difference, the intermediate speed reduction array during torque building, the intermediate speed reduction array during torque unloading, the free descent speed difference during the torque building response interval, and the free descent speed difference during the torque unloading response interval.

[0029] Optionally, obtaining the theoretical total braking time array based on the stable braking demand speed difference array and the first brake basic characteristic parameter array includes:

[0030] The theoretical total braking time array is obtained based on the array of maximum deceleration slope of the intermediate shaft and the array of stable braking demand speed difference.

[0031] Optionally, obtaining the theoretical total braking time based on the first brake basic characteristic parameter array and the theoretical stable braking demand time array includes:

[0032] The torque build-up time, torque release time, and torque release response time are obtained from the first brake's basic characteristic parameter array.

[0033] The theoretical total braking time is obtained based on the torque build-up time, torque release time, torque release response time, and theoretical stable braking time array.

[0034] Optionally, after obtaining the difference between the total demand braking target time and the theoretical total demand braking time, selecting the theoretical total demand braking time corresponding to the smallest difference, and determining the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total demand braking time, the method further includes:

[0035] The torque build-up response time is obtained based on the actual opening time of the intake valve.

[0036] Obtain the initial intermediate shaft speed difference and initial intermediate shaft speed at the moment the intake valve opening command is given;

[0037] The timing of the intake valve opening command is obtained, and the timing of the stable braking timer is set.

[0038] The required detangle time is obtained based on the timing time and the actual opening time of the intake valve.

[0039] Get the current deceleration slope of the intermediate shaft;

[0040] The change in intermediate shaft deceleration during the torque unloading process is determined based on the required torque unloading time and the current intermediate shaft deceleration slope.

[0041] Obtain the target feed speed difference of the main gearbox and the current intermediate shaft speed;

[0042] The torque-building and stable braking required speed difference is determined based on the initial intermediate shaft speed difference, the main gearbox target feed speed difference, and the intermediate shaft speed reduction change value during the torque unloading process.

[0043] The remaining braking speed difference is determined based on the speed difference between torque build-up and stable braking requirements, the starting intermediate shaft speed, and the current intermediate shaft speed.

[0044] Obtain the torque unloading response time;

[0045] The required stable braking time is determined based on the timing time, the remaining braking demand speed difference, the current intermediate shaft deceleration slope, and the torque unloading response time.

[0046] Determine whether the value obtained by dividing the remaining braking demand speed difference by the current intermediate shaft deceleration slope and then subtracting the torque unloading response time is zero or whether the timing time is equal to the demand stable braking time.

[0047] If so, the exhaust valve of the intermediate shaft brake will exhaust air;

[0048] If not, the exhaust valve of the intermediate shaft brake continues to maintain pressure.

[0049] Optionally, obtaining the torque build-up response time based on the actual opening time of the intake valve includes:

[0050] Based on the actual opening time of the intake valve, the main air chamber pressure and the current transmission oil temperature of the current transmission valve block are obtained again.

[0051] Get the second set intake valve opening time array;

[0052] The main air chamber pressure of the current transmission valve block and the second brake basic characteristic parameter array at the current transmission oil temperature are determined according to the second set intake valve opening time array.

[0053] The torque build-up response time is obtained based on the second brake's basic characteristic parameter array;

[0054] The acquisition of the initial intermediate shaft speed difference and the initial intermediate shaft speed at the moment the intake valve opening command is given includes:

[0055] Obtain the current intermediate shaft speed, the target gear auxiliary gearbox ratio, and the target gear main gearbox ratio;

[0056] The target intermediate shaft speed in the target gear is obtained based on the current intermediate shaft speed, the target gear auxiliary gearbox speed ratio, and the target gear main gearbox speed ratio.

[0057] Get the intermediate shaft speed at the moment braking begins and the initial intermediate shaft speed in the current gear;

[0058] The difference between the initial intermediate shaft speed at the time the intake valve opening command is given is determined based on the target intermediate shaft speed in the target gear and the intermediate shaft speed at the time the braking begins in the current gear.

[0059] According to another aspect of the present invention, a vehicle is provided, comprising:

[0060] At least one processor; and

[0061] A memory communicatively connected to the at least one processor; wherein,

[0062] The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the control method for the transmission intermediate shaft brake as described in any of the preceding aspects.

[0063] According to another aspect of the present invention, a computer-readable storage medium is provided, characterized in that the computer-readable storage medium stores computer instructions for causing a processor to execute and implement the control method for the intermediate shaft brake of the transmission as described in any of the above aspects.

[0064] The technical solution of this invention involves: activating the intermediate shaft brake; obtaining an estimated target speed difference at the start of braking; obtaining an array of basic characteristic parameters of the first brake; obtaining an array of stable braking demand speed differences based on the estimated target speed difference at the start of braking and the array of basic characteristic parameters of the first brake; obtaining an array of theoretical stable braking demand time based on the array of stable braking demand speed differences and the array of basic characteristic parameters of the first brake; obtaining the theoretical total braking demand time based on the array of basic characteristic parameters of the first brake and the array of theoretical stable braking demand time; determining the total braking target time under different upshift types; obtaining the difference between the total braking target time and the theoretical total braking time; selecting the theoretical total braking time corresponding to the smallest difference; and determining the actual opening time of the intake valve of the intermediate shaft brake based on the theoretical total braking time. Confirming the actual opening time of the intake valve of the intermediate shaft brake ensures precise control of the intermediate shaft brake, improving the smoothness and speed of the shifting process.

[0065] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0066] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0067] Figure 1 is a schematic flowchart of a control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0068] Figure 2 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0069] Figure 3 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0070] Figure 4 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0071] Figure 5 is a schematic diagram of the intermediate shaft slope model structure during the braking torque building process provided in an embodiment of the present invention;

[0072] Figure 6 is a schematic diagram of the intermediate shaft slope model structure during braking torque unloading provided in an embodiment of the present invention;

[0073] Figure 7 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0074] Figure 8 is a schematic diagram of the intermediate shaft slope model structure during the braking torque building, stable braking and torque unloading process provided in an embodiment of the present invention;

[0075] Figure 9 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0076] Figure 10 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0077] Figure 11 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0078] Figure 12 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention;

[0079] Figure 13 is a schematic flowchart of a control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. Detailed Implementation

[0080] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0081] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0082] Figure 1 is a schematic flowchart of a control method for a transmission intermediate shaft brake according to an embodiment of the present invention. This embodiment is applicable to the control of a transmission intermediate shaft brake. The method can be executed by a control device for the transmission intermediate shaft brake, which can be implemented in hardware and / or software. The method includes:

[0083] S101, activate the intermediate shaft brake.

[0084] The intermediate brake will only operate if the intermediate brake meets the opening conditions; otherwise, it will not operate. After the intermediate axle brake meets the opening conditions, the intermediate axle speed sensor calculates the natural deceleration slope of the intermediate axle and records the free deceleration slope of the intermediate axle at the moment the brake intake command is issued. This value should be negative and should not be less than the free deceleration slope measured at the same temperature when static shifting is performed while the vehicle is stationary.

[0085] S102, obtain the estimated value of the target speed difference at the moment of braking start.

[0086] Specifically, the target intermediate shaft speed in the target gear and the intermediate shaft speed at the moment braking begins in the current gear are obtained, and then the estimated value of the target speed difference at the moment braking begins is obtained based on the target intermediate shaft speed in the target gear and the intermediate shaft speed at the moment braking begins in the current gear.

[0087] S103, obtain the array of basic characteristic parameters of the first brake.

[0088] Among them, the basic characteristic parameter array of the first braking system can be obtained by software adaptively summarizing and recording during vehicle gear shifting or by bench testing.

[0089] S104. Obtain the stable braking demand speed difference array based on the target speed difference estimate at the braking start time and the basic characteristic parameter array of the first brake.

[0090] Specifically, based on the basic characteristic parameter array of the first brake, the intermediate shaft speed reduction array during torque building, the intermediate shaft speed reduction array during torque unloading, the target gear speed difference equivalent to the intermediate shaft speed difference, the speed difference that freely decreases during torque building response, and the speed difference that decreases during torque unloading response are obtained. Combined with the estimated value of the target speed difference at the start of braking, the stable braking demand speed difference array is obtained.

[0091] S105, obtain the theoretical stable braking demand time array based on the stable braking demand speed difference array and the first brake basic characteristic parameter array.

[0092] S106, obtain the theoretical total braking time based on the array of basic characteristic parameters of the first brake and the array of theoretical stable braking time.

[0093] Specifically, the torque build-up time, torque release time, and torque unloading response time are obtained from the basic characteristic parameter array of the first brake, and the theoretical stable braking demand time array is obtained by combining the stable braking demand speed difference array.

[0094] S107, determine the total required braking target time under different upshift types.

[0095] The total braking target time for different upshift types can be obtained by summarizing multiple vehicle driving and shifting operations. For example, the total braking time target for continuous upshifting on flat roads is 200ms, the total braking time target for skipping one gear is 310ms, the total braking time target for continuous upshifting on a 10% slope is 300ms, and the total braking time target for skipping one gear is 410ms, etc. The specific time can be set according to actual conditions.

[0096] S108, obtain the difference between the total demand braking target time and the theoretical total demand braking time, select the theoretical total demand braking time corresponding to the smallest difference, and determine the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total demand braking time.

[0097] Specifically, it is necessary to ensure that all values ​​in the theoretical stable braking demand time array are greater than or equal to zero. The difference between the total braking target time and the theoretical total braking demand time is compared, and the theoretical total braking demand time corresponding to the smallest difference is selected. Then, the corresponding intake valve opening time is obtained based on the theoretical total braking time, which is used as the actual intake valve opening time for this intermediate shaft braking operation. If the theoretical stable braking demand time array Δt... wz Under the premise that it is greater than or equal to zero, if the theoretical stable braking demand time array Δt wz Greater than or equal to the maximum estimated allowable stable braking time Δt set And Δt satisfies the condition wz If the element in the corresponding array is not the first element, then the next longer valve opening time corresponding to the theoretical total braking time with the smallest difference is selected. If the condition is not met, the valve opening time corresponding to the theoretical total braking time with the smallest difference is selected. The valve opening time in the basic characteristic parameter array of the first brake system is continuously updated during the timing of the stable braking time timer. When the stable braking time timer is reset to 0, it remains at the value of the previous moment. After the intermediate shaft brake opening condition is met, the brake intake command is issued, and the stable braking time timer starts to accumulate. In this embodiment of the invention, the control duty cycle output when the intake valve is open is 100%, and the control duty cycle is 0 when the intake valve is not open.

[0098] This invention, through obtaining the target speed difference estimate at the braking start moment, the basic characteristic parameter array of the first brake, and determining the total required braking target time under different upshift types, confirms the actual valve opening time of the intake valve of the intermediate shaft brake, thereby ensuring precise control of the intermediate shaft brake and improving the smoothness and speed of the shifting process.

[0099] Optionally, Figure 2 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. As shown in Figure 2, the method includes:

[0100] S201, activate the intermediate shaft brake.

[0101] S202, obtain the target intermediate shaft speed in the target gear.

[0102] The rotational speed n is obtained through the output shaft speed sensor. out And obtain the target gear ratio of the auxiliary gearbox i rc The gear ratio i of the target gearbox mb Then, the target intermediate shaft speed n at the target gear is calculated according to the formula. lbtgact =n out *i rc *i mb .

[0103] S203, obtain the intermediate shaft speed at the moment braking begins in the current gear.

[0104] S204, determine the estimated value of the difference between the target intermediate shaft speed at the start of braking based on the target intermediate shaft speed in the target gear and the intermediate shaft speed at the start of braking in the current gear.

[0105] Among them, the target intermediate shaft speed n at the moment of braking start is obtained. lbtgini The speed reduction slope dn of the gearbox main shaft at the moment of braking initiation. MB Based on the road slope calculated by slope sensors or slope estimation methods, the rotational speed of the main shaft going uphill is reduced by the slope dn. MB dn MB The value is limited to no greater than 0, and the speed reduction slope dn of the main shaft on the downhill slope is reduced. MB Given a value greater than 0, the total braking time dt is obtained, and the intermediate shaft speed in the target gear is n. lbtg =n lbtgini +dn MB *i mb *(dt+Δt zs In the formula, Δt zs To establish the torsional response time, dt and Δt zs An initial setting is used before the process is finalized. This initial setting is related to continuous upshifting and skip-gear modes. For example, for continuous upshifting, the initial setting is 200ms, and for skip-gear upshifting, it is 310ms. The intermediate shaft speed n is measured by the intermediate shaft speed sensor at the moment braking begins in the current gear. lbcu Calculate the estimated value Δn of the target speed difference at the start of braking. 开始估 =n lbcu -n lbtg The estimated value of the target speed difference at the moment of braking initiation Δn 开始估 It is continuously updated during the intermediate shaft braking process.

[0106] S205, obtain the array of basic characteristic parameters of the first brake.

[0107] S206, obtain the stable braking demand speed difference array based on the target speed difference estimate at the braking start time and the basic characteristic parameter array of the first brake.

[0108] S207, obtain the theoretical stable braking demand time array based on the stable braking demand speed difference array and the basic characteristic parameter array of the first brake.

[0109] S208, obtain the theoretical total braking time based on the array of basic characteristic parameters of the first brake and the array of theoretical stable braking time.

[0110] S209, determine the total required braking target time under different upshift types.

[0111] S210, obtain the difference between the total demand braking target time and the theoretical total demand braking time, select the theoretical total demand braking time corresponding to the smallest difference, and determine the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total demand braking time.

[0112] This invention determines the estimated difference between the target speed at the start of braking and the target intermediate shaft speed in the target gear and the intermediate shaft speed at the start of braking in the current gear, obtains the basic characteristic parameter array of the first brake, and determines the total required braking target time under different upshift types. It also confirms the actual opening time of the intake valve of the intermediate shaft brake, which can ensure precise control of the intermediate shaft brake and improve the smoothness and speed of the shifting process.

[0113] Optionally, Figure 3 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. As shown in Figure 3, the method includes:

[0114] S301, engage the intermediate shaft brake.

[0115] S302, obtain the estimated value of the target speed difference at the moment of braking start.

[0116] S303, obtain the current main air chamber pressure of the transmission valve block and the current transmission oil temperature.

[0117] Specifically, the air pressure sensor inside the valve block in the transmission obtains the current air pressure in the main air chamber of the transmission valve block, and the temperature sensor obtains the current transmission oil temperature.

[0118] S304, Get the array of set intake valve opening times.

[0119] For example, the intake valve opening time array can be set as [0,5,10,15,20,25,30,35,40,50], where each number corresponds to an intake valve opening time setting.

[0120] S305, determine the main air chamber pressure of the current transmission valve block and the basic characteristic parameter array of the first brake at the current transmission oil temperature based on the set intake valve opening time array.

[0121] Specifically, the first brake basic characteristic parameter array corresponding to the intake valve opening time array is set based on the current main air chamber pressure of the transmission valve block and the current transmission oil temperature.

[0122] S306, obtain the stable braking demand speed difference array based on the target speed difference estimate at the braking start time and the basic characteristic parameter array of the first brake.

[0123] S307, obtain the theoretical stable braking demand time array based on the stable braking demand speed difference array and the basic characteristic parameter array of the first brake.

[0124] S308, obtain the theoretical total braking time based on the array of basic characteristic parameters of the first brake and the array of theoretical stable braking time.

[0125] S309, determine the total required braking target time under different upshift types.

[0126] S310, obtain the difference between the total demand braking target time and the theoretical total demand braking time, select the theoretical total demand braking time corresponding to the smallest difference, and determine the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total demand braking time.

[0127] This invention obtains the basic characteristic parameter array of the first brake by using the main air chamber pressure of the current transmission valve block, the current transmission oil temperature, and the intake valve opening time array. Then, in conjunction with the estimated target speed difference at the start of braking and the determination of the total required braking target time under different upshift types, the actual opening time of the intake valve of the intermediate shaft brake is confirmed, which can ensure precise control of the intermediate shaft brake and improve the smoothness and speed of the shifting process.

[0128] Optionally, Figure 4 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. As shown in Figure 4, the method includes:

[0129] S401, engage the intermediate shaft brake.

[0130] S402, obtain the estimated value of the target speed difference at the moment of braking start.

[0131] S403, obtain the array of basic characteristic parameters of the first brake.

[0132] S404: Obtain the air pressure value array, torque build-up time array, and torque release time array corresponding to the valve opening time based on the basic characteristic parameter array of the first brake.

[0133] S405, obtain the maximum deceleration slope array of the intermediate shaft based on the air pressure data.

[0134] Specifically, the air pressure value array corresponding to the valve opening time is obtained based on the basic characteristic parameter array of the first brake, and the theoretical maximum pressure drop slope of the intermediate shaft under each air pressure value is calculated, forming an array of the maximum speed drop slope of the intermediate shaft corresponding one-to-one with the air pressure value.

[0135] S406, obtain the intermediate deceleration array during torque build-up based on the maximum deceleration slope array of the intermediate shaft and the torque build-up time array.

[0136] Figure 5 is a schematic diagram of the intermediate shaft slope model structure during the braking torque build-up process provided by an embodiment of the present invention, showing the speed slope of the intermediate shaft during the process of the brake torque being built up to the maximum braking capacity. It can be approximated as an upward-opening parabolic function, with the braking command given at time t. zs Add the torsional response time Δt zs The time after that point is taken as the starting time 0, which can be represented as (0, 0). The slope of the parabola, with the rotational speed of the intermediate shaft at the moment the brake reaches its maximum braking capacity, can then be represented as... As shown in Figure 5, the expression for the slope of the intermediate shaft during the torsion modeling process can be derived from the above parameters: This leads to the derivation of the torque time t. z Changes in rotational speed difference over time: The maximum braking slope Add the free deceleration slope at the moment the braking command is issued to the theoretically calculated maximum deceleration slope of the intermediate shaft. The sum; for each element in the torque build-up time array and the intermediate shaft maximum speed reduction slope array in the basic characteristic parameter array of the first brake, the intermediate shaft speed reduction speed is calculated, and the intermediate speed reduction array Δn is formed during the torque build-up process. ZJ .

[0137] S407, determine the intermediate speed reduction array during torque unloading based on the array of maximum speed reduction slope of the intermediate shaft and the array of torque unloading time.

[0138] Figure 6 is a schematic diagram of the intermediate shaft slope model structure during the braking torque release process provided by an embodiment of the present invention, showing the rotational speed slope of the intermediate shaft during the braking torque release process. It can be approximated as a downward-opening parabolic function, given by the moment of the brake torque release command plus the torque release response time (t). ze +Δt rel The time after (0, 0) is taken as the starting time 0, which can be represented as (0, 0). The slope of the intermediate shaft's rotational speed at this time is the coordinate value of the y-axis corresponding to the 0 point of the x-axis of the coordinate system, which can be represented as (0, 0). The time to complete the brake torque release is minus the time when the brake torque release command is given, and then the torque release response time is subtracted (t). rel -t ze -Δt rel The time t is the time when the brake is released. s The slope of the intermediate shaft's rotational speed at the moment the brake is released is the coordinate value of the intersection of the x-axis corresponding to the 0 point of the y-axis in the coordinate system, which can be expressed as (t s , 0), this value is the vertex of the parabola, as shown in Figure 6. From the above parameters, the expression for the slope of the intermediate axis during the torque unloading process of this model can be derived: This leads to the deduction of t. s Changes in rotational speed difference over time: The maximum braking slope in the above formula Add the free deceleration slope at the moment the braking command is issued to the theoretically calculated maximum deceleration slope of the intermediate shaft. The sum; for each element in the torque unloading time array and the maximum speed reduction slope array in the basic characteristic parameter array of the first brake, the intermediate shaft speed reduction speed is calculated, and the intermediate speed reduction array Δn is formed during the torque unloading process. JZ .

[0139] S408, obtain the intermediate shaft speed difference, the free descent speed difference in the torque build-up response range, and the free descent speed difference in the torque unload response range.

[0140] Wherein, the time t when the brake is completely released rel The speed difference between the target gear and the sliding sleeve should be exactly the optimal feed speed difference, and at this point, the sliding sleeve and the target gear should just be in contact. At this point, the speed difference is taken as the average of the upper and lower limits, and needs to be converted to the equivalent speed difference Δn of the intermediate shaft. 进齿 .

[0141] S409, obtain the stable braking demand speed difference array based on the target speed difference estimate at the braking start time, the intermediate shaft speed difference, the intermediate speed reduction array during torque build-up, the intermediate speed reduction array during torque unloading, the free descent speed difference in the torque build-up response interval, and the free descent speed difference in the torque unloading response interval.

[0142] The formula for obtaining the stable braking demand speed difference array is as follows: Where, Δn 开始估 The estimated value of the target speed difference at the moment of braking start, Δn 进齿 The intermediate shaft speed difference, Δn ZJ To construct the intermediate deceleration array and Δn during the torsion process JZ This is an array for intermediate speed reduction during torque unloading. To establish the free descent speed difference within the torque response range, The free descent speed difference within the torque response range.

[0143] S410: Obtain the theoretical stable braking demand time array based on the stable braking demand speed difference array and the first brake basic characteristic parameter array.

[0144] S411, obtain the theoretical total braking time based on the array of basic characteristic parameters of the first brake and the array of theoretical stable braking time.

[0145] S412, determine the total required braking target time under different upshift types.

[0146] S413, obtain the difference between the total demand braking target time and the theoretical total demand braking time, select the theoretical total demand braking time corresponding to the smallest difference, and determine the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total demand braking time.

[0147] This invention obtains the maximum speed reduction slope array, torque build-up time array, and torque unloading time array of the intermediate shaft through the basic characteristic parameter array of the first brake. Then, it obtains the intermediate speed reduction array during torque build-up, the intermediate speed reduction array during torque unloading, the free fall speed difference in the torque build-up response interval, and the free fall speed difference in the torque unloading response interval. Combined with the estimated target speed difference at the start of braking and the determination of the total required braking target time under different upshift types, the actual valve opening time of the intake valve of the intermediate shaft brake is confirmed. This ensures precise control of the intermediate shaft brake and improves the smoothness and speed of the shifting process.

[0148] Optionally, Figure 7 is a flowchart illustrating another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. As shown in Figure 7, the method includes:

[0149] S501, activate the intermediate shaft brake.

[0150] S502, obtain the estimated value of the target speed difference at the moment of braking start.

[0151] S503, obtain the array of basic characteristic parameters of the first brake.

[0152] S504, obtain the air pressure value array, torque build-up time array, and torque unloading time array corresponding to the valve opening time based on the basic characteristic parameter array of the first brake.

[0153] S505, obtains the maximum deceleration slope array of the intermediate shaft based on air pressure data.

[0154] S506, obtain the intermediate deceleration array during torque build-up based on the maximum deceleration slope array of the intermediate shaft and the torque build-up time array.

[0155] S507, determine the intermediate speed reduction array during torque unloading based on the maximum speed reduction slope array of the intermediate shaft and the torque unloading time array.

[0156] S508, obtain the intermediate shaft speed difference, the free descent speed difference in the torque build-up response range, and the free descent speed difference in the torque unload response range.

[0157] S509, obtain the stable braking demand speed difference array based on the target speed difference estimate at the braking start time, the intermediate shaft speed difference, the intermediate speed reduction array during torque building, the intermediate speed reduction array during torque unloading, the free descent speed difference in the torque building response interval, and the free descent speed difference in the torque unloading response interval.

[0158] S510 obtains the theoretical total braking time array based on the array of maximum speed reduction slope of the intermediate shaft and the array of stable braking demand speed difference.

[0159] Figure 8 is a schematic diagram of the intermediate shaft slope model structure during braking torque build-up, stable braking, and torque release processes according to an embodiment of the present invention, showing the stable braking required speed difference array Δn. wz array of maximum deceleration slopes of intermediate shaft Dividing by the other yields the exhaust valve holding time, which is the theoretical total braking time, as shown in Figure 8. The area enclosed by the same curve and the X and y axes represents the change in the speed difference of the intermediate shaft throughout the entire process, excluding the torque build-up response phase. According to the formula... The theoretical total demand braking time array Δt can be calculated. wz .

[0160] S511, obtain the theoretical total braking time based on the array of basic characteristic parameters of the first brake and the array of theoretical stable braking time.

[0161] S512 determines the total required braking target time under different upshift types.

[0162] S513, obtain the difference between the total demand braking target time and the theoretical total demand braking time, select the theoretical total demand braking time corresponding to the smallest difference, and determine the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total demand braking time.

[0163] This invention utilizes the maximum deceleration slope array of the intermediate shaft and the stable braking demand speed difference array to obtain the theoretical total braking time array. Then, in conjunction with the total braking target time under different upshift types, the actual valve opening time of the intake valve for intermediate shaft braking is confirmed, which can ensure precise control of the intermediate shaft brake and improve the smoothness and speed of the shifting process.

[0164] Optionally, Figure 9 is a flowchart illustrating another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. As shown in Figure 9, the method includes:

[0165] S601, engage the intermediate shaft brake.

[0166] S602, obtain the estimated value of the target speed difference at the moment of braking start.

[0167] S603, obtain the array of basic characteristic parameters of the first brake.

[0168] S604: Obtain the stable braking demand speed difference array based on the target speed difference estimate at the braking start time and the basic characteristic parameter array of the first brake.

[0169] S605, obtain the theoretical stable braking demand time array based on the stable braking demand speed difference array and the first brake basic characteristic parameter array.

[0170] S606, obtain the torque build-up time, torque release time, and torque release response time based on the basic characteristic parameter array of the first brake.

[0171] S607, obtain the theoretical total braking time based on the torque build-up time, torque release time, torque release response time and theoretical stable braking demand time array.

[0172] The torque build-up time t is obtained from the basic characteristic parameter array of the first brake. z Unloading time t s and torque unloading response time Δt rel And in conjunction with the theoretically stable braking demand time array Δt wz Calculate the theoretical total demand braking time t zz Satisfying formula t zz =Δt wz +t z +t s +Δt rel .

[0173] S608 determines the total required braking target time under different upshift types.

[0174] S609, obtain the difference between the total demand braking target time and the theoretical total demand braking time, select the theoretical total demand braking time corresponding to the smallest difference, and determine the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total demand braking time.

[0175] This invention obtains the theoretical total braking time by acquiring the torque build-up time, torque release time, torque release response time, and theoretical stable braking demand time array. Combined with the total braking target time under different upshift types, the actual valve opening time of the intake valve of the intermediate shaft brake is confirmed, which can ensure precise control of the intermediate shaft brake and improve the smoothness and speed of the shifting process.

[0176] Optionally, Figure 10 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. As shown in Figure 10, the method includes:

[0177] S701, obtains the torque build-up response time based on the actual opening time of the intake valve.

[0178] Specifically, the torque build-up response time at the actual opening time of the intake valve is determined.

[0179] S702, obtain the starting intermediate shaft speed difference and the starting intermediate shaft speed at the moment the intake valve opening command is given.

[0180] Among them, the rotational speed n is measured by the output shaft speed sensor. out Calculate the target intermediate shaft speed in the target gear, and the target gearbox gear ratio i. rc The gear ratio i of the target gearbox mb Then the target gear intermediate shaft speed n lbtg =n out *i rc *i mb The intermediate shaft speed n is measured by the intermediate shaft speed sensor at the moment when braking begins in the current gear. lbcu Calculate the initial intermediate shaft speed difference Δn at the moment the intake valve opening command is given. 开始 =n lbcu -n lbtg The initial intermediate shaft speed difference given by this intake valve opening command varies with the intermediate shaft speed n during the braking process. out It is continuously updated. The initial intermediate shaft speed is the intermediate shaft speed at the moment the intake valve opening command is given.

[0181] S703, obtains the time given by the intake valve opening command, and stabilizes the timing of the braking timer.

[0182] When the brake intake command is issued, that is, when the intake valve opening command is received, the stable braking time timer starts to accumulate the time, and the timing time can be obtained.

[0183] S704 obtains the required de-torsion time based on the timing time and the actual opening time of the intake valve.

[0184] Specifically, the timing time and the actual opening time of the intake valve are compared, and the minimum value of the two is used to obtain the required braking torque. The required de-torque time is then obtained based on the required braking torque.

[0185] S705, obtain the current intermediate shaft deceleration slope.

[0186] S706 determines the change in intermediate shaft speed reduction during torque unloading based on the required torque release time and the current intermediate shaft speed reduction slope.

[0187] During braking, the deceleration slope of the intermediate shaft is updated in real time. The current deceleration slope of the intermediate shaft is obtained, and the change in deceleration of the intermediate shaft during torque release, Δn, is determined based on the required torque release time and the current deceleration slope. JZ1 .

[0188] S707, obtain the target feed speed difference of the main gearbox and the current intermediate shaft speed.

[0189] S708 determines the torque-building and stable braking speed difference based on the initial intermediate shaft speed difference, the main gearbox target feed speed difference, and the intermediate shaft speed reduction change during torque unloading.

[0190] Specifically, the change in intermediate shaft speed reduction during torque unloading is determined based on the required torque release time and the current intermediate shaft speed reduction slope, satisfying the formula Δn. z =Δn 开始 -|Δn JZ1 |-Δn 进齿1 , where Δn 开始 The initial intermediate shaft speed difference, Δn z To meet the speed difference required for torque generation and stable braking, Δn JZ1 Δn represents the change in the intermediate shaft speed during torque unloading. 进齿1 The difference in feed speed between the main gearbox and the target gear speed, Δn z Updated as the output shaft speed changes, for example, at speed n on an uphill section. out Or decelerate under the action of resistance, Δn 开始 The speed difference Δn required for torque build-up and stable braking will gradually increase. z It will also gradually increase.

[0191] S709 determines the remaining braking speed difference based on the speed difference between torque building and stable braking requirements, the initial intermediate shaft speed, and the current intermediate shaft speed.

[0192] Among them, the speed difference Δn is based on the torque build-up and stable braking requirements. z Initial intermediate shaft speed n z and the current intermediate shaft speed n current According to the formula Δn zleft =Δn z -(n z -n current ), calculate the remaining braking demand speed difference Δn zlef .

[0193] S710, obtain torque unloading response time.

[0194] S711 determines the required stable braking time based on the timing time, the remaining braking demand speed difference, the current intermediate shaft deceleration slope, and the torque unloading response time.

[0195] The stabilization braking time timer starts accumulating, and the timing time t is obtained. timer The remaining braking demand speed difference Δn zlef The deceleration slope of the intermediate shaft during the stable braking phase Torque unloading response time Δt rel Satisfying the formula The pressure holding time of the brake exhaust solenoid valve is obtained, which is the required stable braking time t. z The slope of the intermediate shaft speed during the stable braking phase. It is obtained by real-time differentiation of the intermediate shaft rotation speed acquired by the sensor and then filtered by a first-order filter with a window length of 5ms; on the uphill section, Δn 开始 It will gradually increase, then Δn z It will also gradually increase, Δn zleft It will also gradually increase, thus requiring a stable braking time t z It also gradually increased.

[0196] S712 determines whether the value obtained by dividing the remaining braking demand speed difference by the current intermediate shaft deceleration slope and then subtracting the torque unloading response time is zero or whether the timing time is equal to the required stable braking time.

[0197] Specifically, the value obtained by dividing the remaining braking demand speed difference by the current intermediate shaft deceleration slope and then subtracting the torque unloading response time is zero. Whether it equals zero, or whether the timing time equals the demand stabilization braking time, i.e., t timer Is it equal to t? z .

[0198] S713, if so, the exhaust valve of the intermediate shaft brake will exhaust air.

[0199] If the following conditions are met Equal to zero or t timer equal to t z Then the exhaust valve of the intermediate shaft brake ends the pressure holding and starts to exhaust. At this time, the stable braking timer stops and is reset to 0, which is used to start the operation for the next braking.

[0200] S714, if not, the exhaust valve of the intermediate shaft brake continues to maintain pressure.

[0201] The pressure holding of the exhaust valve depends on the control method of the exhaust solenoid valve. The exhaust solenoid valve can achieve pressure holding when energized and remain open when de-energized, or it can achieve pressure holding when de-energized and remain open when energized. Therefore, pressure holding refers to controlling the exhaust solenoid valve to achieve the pressure holding function. When holding pressure, the output control duty cycle is 100% and 0 when not holding pressure. The controller's underlying software processes the control signal into the actual control signal loaded onto the exhaust solenoid valve according to the control method of the exhaust solenoid valve.

[0202] If a set time Δt elapses after the exhaust valve is de-energized and exhaust is released, i.e., the torque relief response time Δt rel Adding torque release time t s intermediate shaft speed n out Still higher than the fine-tuning set speed n wtIf the torque transmitted by the main clutch connected to the input shaft is not higher than 0 Nm, then the secondary braking of the intermediate brake is initiated, and the actual opening time of the intake valve, the required stable braking time, and the timing of the exhaust valve de-energization are calculated again; if the intermediate shaft speed is n out Not higher than the fine-tuning set speed n wt If the intermediate brake is not applied, the secondary braking of the intermediate brake will not be performed, and the operation will continue.

[0203] After determining the required stable braking time for the intermediate shaft brake and the exhaust valve's exhaust time, the process also includes calculating the timing of the main gearbox shift command issued for shift timing overlap control. Specific steps include: obtaining the main gearbox's shift action response time as Δt. MB This value refers to the time from when the main gearbox shift command is issued to when the sliding sleeve and the target gear contact. This value can be the maximum value from theoretical calculations, bench tests, or online self-learning results of the control system. In other words, it is stored based on data obtained from multiple shift operations in the system and is continuously updated, then selected from the database. Based on the control method determined by the actual opening time of the intake valve, the torque release time ts and the torque unloading response time Δtrel are obtained. When Δt... MB ≤t s +Δt rel After the torque is released, i.e., after the brake is released, the timer starts counting and accumulating timer1. Then, when t s +Δt rel -timer1≤Δt MB At that time, the main gearbox solenoid valve issues a shift command; when t s +Δt rel <Δt MB ≤t s +Δt rel +t z Obtain the time t required for stable braking. z When t z +t s +Δt rel -timer1≤Δt MB When the above-mentioned main gearbox shifting time condition is met, the main gearbox shifting is executed, that is, the main gearbox shifting solenoid valve command is issued.

[0204] By confirming the required stable braking time of the intermediate shaft brake and the exhaust time of the exhaust valve, the embodiments of the present invention can ensure precise control of the intermediate shaft brake and improve the smoothness and speed of the shifting process.

[0205] Optionally, Figure 11 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. As shown in Figure 11, step S701 specifically includes:

[0206] S7011, based on the actual opening time of the intake valve, obtain the main air chamber pressure and the current transmission oil temperature of the current transmission valve block.

[0207] S7012, obtain the second set intake valve opening time array.

[0208] S7013, determine the main air chamber pressure of the current transmission valve block and the second brake basic characteristic parameter array under the current transmission oil temperature based on the second set intake valve opening time array.

[0209] S7014, obtain the torque build-up response time based on the array of basic characteristic parameters of the second brake.

[0210] Specifically, based on the actual opening time of the intake valve, the air pressure sensor in the valve block of the transmission obtains the main air chamber pressure of the current transmission valve block again, and at the same time obtains the current transmission oil temperature and the second set intake valve opening time array. Based on the current main air chamber pressure of the transmission valve block and the current transmission oil temperature, the second brake basic characteristic parameter array corresponding to the second set intake valve opening time array is obtained.

[0211] Figure 12 is a schematic flowchart of another control method for a transmission intermediate shaft brake provided in an embodiment of the present invention. As shown in Figure 12, step S702 specifically includes:

[0212] S7021, obtain the current intermediate shaft speed, the target gear auxiliary gearbox speed ratio, and the target gear main gearbox speed ratio.

[0213] S7022: Obtain the target intermediate shaft speed in the target gear based on the current intermediate shaft speed, the gear ratio of the auxiliary gearbox in the target gear, and the gear ratio of the main gearbox in the target gear.

[0214] S7023, obtain the intermediate shaft speed at the moment braking begins and the initial intermediate shaft speed in the current gear.

[0215] S7024 determines the difference in starting intermediate shaft speed at the time the intake valve opening command is given, based on the target intermediate shaft speed in the target gear and the intermediate shaft speed at the start of braking in the current gear.

[0216] Among them, after determining the actual opening time of the intake valve, the rotational speed n measured by the output shaft speed sensor is used. out And obtain the target gear ratio of the auxiliary gearbox i rc The gear ratio i of the target gearbox mb Calculate the target intermediate shaft speed in the target gear, then the intermediate shaft speed in the target gear is n. lbtg =n out *i rc *i mb The intermediate shaft speed n is measured by the intermediate shaft speed sensor at the moment the braking begins in the current gear. lbcuCalculate the initial intermediate shaft speed difference Δn at the moment the intake valve opening command is given. 开始 =n lbcu -n lbtg ,Δn 开始 During the braking process of the intermediate shaft, n out It keeps updating.

[0217] Figure 13 is a schematic flowchart of a control method for a transmission intermediate shaft brake according to an embodiment of the present invention. As shown in Figure 13, Figure 13 also shows a schematic diagram of a vehicle 10 that can be used to implement an embodiment of the present invention. The vehicle is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The vehicle can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (such as helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the invention described and / or claimed herein.

[0218] As shown in Figure 13, the vehicle 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer programs stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 can also store various programs and data required for the operation of the vehicle 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0219] Multiple components in vehicle 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows vehicle 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0220] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as the control method for a transmission intermediate shaft brake.

[0221] In some embodiments, the control method for the transmission intermediate shaft brake may be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on vehicle 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the control method for the transmission intermediate shaft brake described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to perform the control method for the transmission intermediate shaft brake by any other suitable means (e.g., by means of firmware).

[0222] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0223] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0224] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0225] To provide interaction with the user, the systems and technologies described herein can be implemented in a vehicle having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the vehicle. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0226] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0227] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0228] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0229] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A control method for a transmission intermediate shaft brake, characterized in that, include: Engage the intermediate shaft brake; Obtain the estimated value of the target speed difference at the moment braking begins; Obtain the first brake basic characteristic parameter array; obtain the stable braking demand speed difference array based on the target speed difference estimate at the braking start time and the first brake basic characteristic parameter array; obtain the theoretical stable braking demand time array based on the stable braking demand speed difference array and the first brake basic characteristic parameter array; obtain the theoretical total braking demand time based on the first brake basic characteristic parameter array and the theoretical stable braking demand time array; determine the total braking target time under different upshift types; Obtain the difference between the total required braking target time and the theoretical total required braking time, select the theoretical total required braking time corresponding to the smallest difference, and determine the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total required braking time.

2. The control method for the intermediate shaft brake of the transmission according to claim 1, characterized in that, Obtaining the target speed difference estimate at the start of braking includes: obtaining the target intermediate shaft speed in the target gear; obtaining the intermediate shaft speed at the start of braking in the current gear; and determining the target speed difference estimate at the start of braking based on the target intermediate shaft speed in the target gear and the intermediate shaft speed at the start of braking in the current gear.

3. The control method for the intermediate shaft brake of the transmission according to claim 1, characterized in that, Obtaining the array of basic characteristic parameters of the first brake includes: obtaining the main air chamber pressure and the current transmission oil temperature of the current transmission valve block; obtaining the set intake valve opening time array; and determining the array of basic characteristic parameters of the first brake under the current transmission valve block pressure and the current transmission oil temperature based on the set intake valve opening time array.

4. The control method for the intermediate shaft brake of the transmission according to claim 1, characterized in that, Obtaining the stable braking demand speed difference array based on the estimated target speed difference at the braking start time and the first brake's basic characteristic parameter array includes: obtaining the air pressure value array, torque build-up time array, and torque unloading time array corresponding to the valve opening time based on the first brake's basic characteristic parameter array; obtaining the intermediate shaft maximum speed reduction slope array based on the air pressure value data; obtaining the intermediate speed reduction array during torque build-up based on the intermediate shaft maximum speed reduction slope array and the torque build-up time array; determining the intermediate speed reduction array during torque unloading based on the intermediate shaft maximum speed reduction slope array and the torque unloading time array; obtaining the intermediate shaft speed difference, the free descent speed difference during the torque build-up response interval, and the free descent speed difference during the torque unloading response interval; and obtaining the stable braking demand speed difference array based on the estimated target speed difference at the braking start time, the intermediate shaft speed difference, the intermediate speed reduction array during torque build-up, the intermediate speed reduction array during torque unloading, the free descent speed difference during the torque build-up response interval, and the free descent speed difference during the torque unloading response interval.

5. The control method for the intermediate shaft brake of the transmission according to claim 4, characterized in that, The theoretical stable braking demand time array is obtained based on the stable braking demand speed difference array and the first brake basic characteristic parameter array, including: obtaining the theoretical total braking demand time array based on the intermediate shaft maximum speed reduction slope array and the stable braking demand speed difference array.

6. The control method for the intermediate shaft brake of the transmission according to claim 1, characterized in that, Obtaining the theoretical total braking time based on the first brake basic characteristic parameter array and the theoretical stable braking demand time array includes: obtaining the torque build-up time, torque release time, and torque release response time based on the first brake basic characteristic parameter array; and obtaining the theoretical total braking time based on the torque build-up time, the torque release time, the torque release response time, and the theoretical stable braking demand time array.

7. The control method for the intermediate shaft brake of the transmission according to claim 1, characterized in that, After obtaining the difference between the total required braking target time and the theoretical total required braking time, selecting the theoretical total required braking time corresponding to the smallest difference, and determining the actual valve opening time of the intake valve of the intermediate shaft brake based on the theoretical total required braking time, the method further includes: obtaining the torque build-up response time based on the actual valve opening time of the intake valve; obtaining the initial intermediate shaft speed difference and the initial intermediate shaft speed at the moment the intake valve opening command is given; obtaining the timing time of the stable braking timer at the moment the intake valve opening command is given; obtaining the required torque release time based on the timing time and the actual valve opening time of the intake valve; obtaining the current intermediate shaft deceleration slope; determining the intermediate shaft deceleration change value during torque release based on the required torque release time and the current intermediate shaft deceleration slope; obtaining the target feed gear speed difference of the main gearbox and the current intermediate shaft speed; and obtaining the torque build-up response time based on the theoretical total required braking time. The starting intermediate shaft speed difference, the target feed gear speed difference of the main gearbox, and the intermediate shaft deceleration change value during the torque unloading process are used to determine the torque build-up and stable braking demand speed difference; the remaining braking demand speed difference is determined based on the torque build-up and stable braking demand speed difference, the starting intermediate shaft speed, and the current intermediate shaft speed; the torque unloading response time is obtained; the required stable braking time is determined based on the timing time, the remaining braking demand speed difference, the current intermediate shaft deceleration slope, and the torque unloading response time; it is determined whether the value obtained by dividing the remaining braking demand speed difference by the current intermediate shaft deceleration slope and then subtracting the torque unloading response time is zero or whether the timing time is equal to the required stable braking time; if yes, the exhaust valve of the intermediate shaft brake vents; if no, the exhaust valve of the intermediate shaft brake continues to maintain pressure.

8. The control method for the intermediate shaft brake of the transmission according to claim 7, characterized in that, The step of obtaining the torque build-up response time based on the actual opening time of the intake valve includes: obtaining the main chamber air pressure and current transmission oil temperature of the current transmission valve block again based on the actual opening time of the intake valve; obtaining a second set intake valve opening time array; determining a second brake basic characteristic parameter array under the current transmission valve block main chamber air pressure and current transmission oil temperature based on the second set intake valve opening time array; obtaining the torque build-up response time based on the second brake basic characteristic parameter array; the step of obtaining the initial intermediate shaft speed difference and initial intermediate shaft speed at the moment the intake valve opening command is given includes: obtaining the current intermediate shaft speed, the target gearbox ratio, and the target gearbox ratio; obtaining the target intermediate shaft speed in the target gear based on the current intermediate shaft speed, the target gearbox ratio, and the target gearbox ratio; obtaining the intermediate shaft speed at the moment braking begins in the current gear and the initial intermediate shaft speed; determining the initial intermediate shaft speed difference at the moment the intake valve opening command is given based on the target intermediate shaft speed in the target gear and the intermediate shaft speed at the moment braking begins in the current gear.

9. A vehicle, characterized in that, The method includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the control method for the intermediate shaft brake of the transmission according to any one of claims 1-8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the control method for the intermediate shaft brake of the transmission as described in any one of claims 1-8.

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