Methods for generating duty cycle of vehicle hydraulic valves, on-board equipment and vehicles

Abstract

This application discloses a method for generating the duty cycle of a vehicle hydraulic valve, an on-board device, and a vehicle. The method involves constraining the maximum increase and decrease of the duty cycle for multiple wheel brake hydraulic valves, respectively, to determine the duty cycle increase ratio and decrease ratio, thus defining the limits on duty cycle variation. Next, based on the duty cycle increase ratio, decrease ratio, and duty cycle increase / decrease control coefficients, a percentage adjustment optimization coefficient for adjusting each wheel brake hydraulic valve is determined. Finally, based on the percentage adjustment optimization coefficient and the dynamic difference percentage, the execution dynamic percentage is determined, thereby enabling real-time determination of the dynamic duty cycle of multiple wheel brake hydraulic valves. This achieves high-precision control of the smooth change of the vehicle hydraulic valve's duty cycle to the desired duty cycle, effectively ensuring vehicle stability.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to a method for generating the duty cycle of a vehicle hydraulic valve, an on-board device, and a vehicle. Background Technology

[0002] The hydraulic braking system controls the increase and decrease of oil pressure in each hydraulic cylinder by controlling the duty cycle of each hydraulic valve, thereby controlling the braking torque of each brake cylinder. The magnitude of the braking torque corresponds one-to-one with the duty cycle of the brake hydraulic valve. This is especially important when the braking torque needs to be dynamically adjusted according to the vehicle's condition during driving, which involves controlling the duty cycle of each brake hydraulic valve.

[0003] Currently, there is no specific method for controlling the duty cycle of vehicle hydraulic valves. However, if the duty cycles of each brake hydraulic valve cannot be coordinated and cannot simultaneously reach their set target duty cycles, it will lead to large dynamic differences in the braking torque of each brake hydraulic valve, which may induce vehicle instability and safety issues.

[0004] Therefore, existing technologies for controlling the duty cycle of vehicle hydraulic valves have the problem of being unable to control the duty cycle of vehicle hydraulic valves in real time, which makes it difficult to ensure vehicle braking stability. Summary of the Invention

[0005] In view of this, it is necessary to provide a method for generating the duty cycle of a vehicle hydraulic valve, an on-board device, and a vehicle, in order to solve the problem in the prior art that the inability to control the duty cycle of the vehicle hydraulic valve in real time makes it difficult to ensure the vehicle's braking stability.

[0006] To address the aforementioned problems, this invention provides a method for generating the duty cycle of a vehicle hydraulic valve, applicable to multi-wheeled vehicles, comprising:

[0007] Obtain the desired duty cycle and the previous cycle duty cycle of multiple wheel brake hydraulic valves respectively;

[0008] Based on the desired duty cycle and the duty cycle of the previous cycle, determine the dynamic percentage, dynamic difference percentage, duty cycle increase speed control coefficient, and duty cycle decrease speed control coefficient for multiple wheel brake hydraulic valves respectively.

[0009] Obtain the maximum increase and maximum decrease in duty cycle for multiple wheel brake hydraulic valves respectively;

[0010] Based on the maximum increase in duty cycle, the maximum decrease in duty cycle, and the desired duty cycle, determine the limit values ​​for the duty cycle increase ratio and the limit values ​​for the duty cycle decrease ratio.

[0011] The duty cycle increase ratio limit, the duty cycle decrease ratio limit, and the dynamic difference percentage are used to determine the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple.

[0012] Based on the duty cycle increase ratio multiple, duty cycle decrease ratio multiple, duty cycle increase speed control coefficient, and duty cycle decrease speed control coefficient, determine the duty cycle increase dynamic percentage control coefficient and duty cycle decrease dynamic percentage control coefficient for multiple wheel brake hydraulic valves respectively, and determine the smaller value among the duty cycle increase dynamic percentage control coefficient and duty cycle decrease dynamic percentage control coefficient as the percentage adjustment optimization coefficient.

[0013] The dynamic percentage to be executed is determined based on the percentage adjustment of the optimization coefficient and the dynamic difference percentage.

[0014] Based on the execution dynamic percentage, dynamic percentage, expected duty cycle, and previous cycle duty cycle, the dynamic duty cycle of multiple wheel brake hydraulic valves in the current cycle is generated.

[0015] Furthermore, based on the desired duty cycle and the duty cycle of the previous cycle, the dynamic percentage, dynamic difference percentage, duty cycle increase rate control coefficient, and duty cycle decrease rate control coefficient of multiple wheel brake hydraulic valves are determined, including:

[0016] Based on the desired duty cycle and the previous cycle duty cycle, the dynamic percentage of multiple wheel brake hydraulic valves is determined using the dynamic percentage calculation formula.

[0017] Based on the dynamic percentage and the dynamic difference percentage calculation formula, the dynamic difference percentage of multiple wheel brake hydraulic valves is determined.

[0018] Based on the expected duty cycle and the duty cycle of the previous cycle, and using the calculation formulas for the duty cycle increase speed control coefficient and the duty cycle decrease speed control coefficient, the duty cycle increase speed control coefficient and the duty cycle decrease speed control coefficient of multiple wheel brake hydraulic valves are determined respectively.

[0019] The formula for calculating the dynamic percentage is as follows:

[0020] The formula for calculating the percentage of dynamic difference is:

[0021] The formulas for calculating the duty cycle increase / decrease rate control coefficient and the duty cycle decrease / decrease rate control coefficient are as follows:

[0022] Where i represents the number of the multiple wheel brake hydraulic valves, rp(i) represents the dynamic percentage, and r(k-1) represents the value of the valve. i r represents the duty cycle of the previous cycle. i Let b2(i) be the expected duty cycle, Δrp(i) be the dynamic difference percentage, and b2(i) be the value of b2(i). up To add a speed control coefficient to the duty cycle, b2(i)down The speed control coefficient is used to reduce the duty cycle.

[0023] Furthermore, the maximum increase and maximum decrease in duty cycle of multiple wheel brake hydraulic valves are obtained, including:

[0024] The maximum duty cycle increment and maximum duty cycle decrement of multiple wheel brake hydraulic valves, as well as the vehicle task execution cycle, are obtained respectively.

[0025] Based on the maximum duty cycle increment, the maximum duty cycle decrement, and the vehicle task execution cycle, and using the calculation formulas for the maximum duty cycle increase and the maximum duty cycle decrease, the maximum duty cycle increase and the maximum duty cycle decrease are determined respectively.

[0026] The formulas for calculating the maximum increase and decrease of the duty cycle are as follows:

[0027] Where, Δr(i) upmax To increase the duty cycle to its maximum value, Δr(i) downmax To minimize the duty cycle, Δr(i) upmaxone Δr(i) represents the maximum increment of the duty cycle. downmaxone The duty cycle is the maximum reduction, and Δt is the vehicle task execution cycle.

[0028] Furthermore, based on the maximum increase in duty cycle, the maximum decrease in duty cycle, and the desired duty cycle, determine the duty cycle increase ratio limit and the duty cycle decrease ratio limit, including:

[0029] Based on the maximum duty cycle increase, the maximum duty cycle decrease, and the expected duty cycle, and using the calculation formulas for the duty cycle increase ratio limit and the duty cycle decrease ratio limit, the duty cycle increase ratio limit and the duty cycle decrease ratio limit are determined respectively.

[0030] The formulas for calculating the duty cycle increase ratio limit and the duty cycle decrease ratio limit are as follows:

[0031] Where, Δrp(i) upmax To add a ratio limit value to the duty cycle, Δrp(i) downmax Reduce the duty cycle ratio limit value.

[0032] Furthermore, based on the duty cycle increase ratio limit, the duty cycle decrease ratio limit, and the dynamic difference percentage, the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple are determined, including:

[0033] Based on the duty cycle increase ratio limit, the duty cycle decrease ratio limit, and the dynamic percentage, and using the calculation formulas for the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple, determine the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple respectively;

[0034] The formulas for calculating the duty cycle increase ratio and the duty cycle decrease ratio are as follows:

[0035] Where, b1(i) upmax To increase the duty cycle by a factor of b1(i) downmax The duty cycle is reduced by a factor of 1.

[0036] Furthermore, based on the duty cycle increase ratio, duty cycle decrease ratio, duty cycle increase rate control coefficient, and duty cycle decrease rate control coefficient, dynamic percentage control coefficients for duty cycle increase and decrease are determined for multiple wheel brake hydraulic valves. The smaller of these two dynamic percentage control coefficients is then determined as the percentage adjustment optimization coefficient, including:

[0037] Based on the duty cycle increase ratio multiple, duty cycle decrease ratio multiple, duty cycle increase rate control coefficient and duty cycle decrease rate control coefficient, and based on the calculation formula of the duty cycle increase dynamic percentage control coefficient and duty cycle decrease dynamic percentage control coefficient, determine the duty cycle decrease dynamic percentage control coefficient;

[0038] The formulas for calculating the dynamic percentage control coefficient for increasing and decreasing duty cycle are as follows:

[0039] The percentage adjustment optimization coefficient is:

[0040] Where, b(i) up Add a dynamic percentage control factor, b(i), to the duty cycle. down To reduce the duty cycle, the dynamic percentage control coefficient, b2(i) up To add a speed control coefficient to the duty cycle, b2(i) down To reduce the duty cycle, the speed control coefficient, b min Adjust the optimization coefficients as a percentage.

[0041] Furthermore, based on the percentage adjustment of the optimization coefficient and the dynamic difference percentage, the execution dynamic percentage is determined, including:

[0042] The dynamic percentage of execution is determined based on the percentage adjustment optimization coefficient and dynamic difference percentage, and the dynamic percentage of execution is calculated using the dynamic percentage of execution formula.

[0043] The formula for calculating the dynamic percentage is as follows:

[0044] Where Δrp1(i) represents the percentage of dynamic execution.

[0045] Furthermore, based on the execution dynamic percentage, dynamic percentage, desired duty cycle, and previous cycle duty cycle, the dynamic duty cycle of multiple wheel brake hydraulic valves in the current cycle is generated, including:

[0046] Based on the execution dynamic percentage, dynamic percentage, expected duty cycle, and previous cycle duty cycle, the dynamic duty cycle of multiple wheel brake hydraulic valves in the current cycle is generated according to the dynamic duty cycle calculation formula.

[0047] The formula for calculating the dynamic duty cycle is as follows:

[0048] Where, r(k) i This refers to the dynamic duty cycle.

[0049] To address the aforementioned problems, the present invention also provides an in-vehicle device, comprising: a processor and a memory; the memory storing a computer-readable program executable by the processor;

[0050] When the processor executes a computer-readable program, it implements the steps in the vehicle hydraulic valve duty cycle generation method described above.

[0051] To address the aforementioned problems, the present invention also provides a vehicle including the vehicle-mounted equipment as described above.

[0052] The beneficial effects of adopting the above technical solution are as follows: This invention provides a method for generating the duty cycle of a vehicle hydraulic valve, an on-board device, and a vehicle. The method involves constraining the maximum increase and decrease of the duty cycle for multiple wheel brake hydraulic valves, respectively, to determine the duty cycle increase ratio and decrease ratio, thereby defining the limits on duty cycle changes. Next, based on the duty cycle increase ratio, decrease ratio, duty cycle increase rate control coefficient, and decrease rate control coefficient, a percentage adjustment optimization coefficient for adjusting each wheel brake hydraulic valve is determined. Finally, based on the percentage adjustment optimization coefficient and the dynamic difference percentage, the execution dynamic percentage is determined, thereby enabling real-time determination of the dynamic duty cycle of multiple wheel brake hydraulic valves. This achieves high-precision control of the vehicle hydraulic valves' duty cycle, allowing for a smooth and simultaneous change to the desired duty cycle, effectively ensuring vehicle stability. Attached Figure Description

[0053] Figure 1 A flowchart illustrating an embodiment of the vehicle hydraulic valve duty cycle generation method provided by the present invention;

[0054] Figure 2 A flowchart illustrating an embodiment of the present invention for determining dynamic percentage, dynamic difference percentage, duty cycle increase rate control coefficient, and duty cycle decrease rate control coefficient;

[0055] Figure 3This is a schematic flowchart illustrating an embodiment of the present invention for obtaining the maximum value of duty cycle increase and the maximum value of duty cycle decrease. Detailed Implementation

[0056] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0057] Before describing the embodiments, the duty cycle of the vehicle hydraulic valve will be explained:

[0058] The duty cycle of a vehicle's hydraulic valve refers to the proportion of working time relative to the total time within a single task execution cycle.

[0059] The hydraulic braking system controls the increase and decrease of oil pressure in each hydraulic cylinder by controlling the duty cycle of each hydraulic valve, thereby controlling the braking torque of each brake cylinder. The magnitude of the braking torque corresponds one-to-one with the duty cycle of the brake hydraulic valve. This is especially important when the braking torque needs to be dynamically adjusted according to the vehicle's condition during driving, which involves controlling the duty cycle of each brake hydraulic valve.

[0060] Currently, there is no specific method for controlling the duty cycle of vehicle hydraulic valves. However, if the duty cycles of each brake hydraulic valve cannot be coordinated and cannot simultaneously reach their set target duty cycles, it will lead to large dynamic differences in the braking torque of each brake hydraulic valve, which may induce vehicle instability and safety issues.

[0061] Therefore, existing technologies for controlling the duty cycle of vehicle hydraulic valves have the problem of being unable to control the duty cycle of vehicle hydraulic valves in real time, which makes it difficult to ensure vehicle braking stability.

[0062] To address the aforementioned problems, this invention provides a method for generating the duty cycle of a vehicle hydraulic valve, an on-board device, and a vehicle, which will be described in detail below.

[0063] like Figure 1 As shown, Figure 1 A flowchart illustrating an embodiment of the vehicle hydraulic valve duty cycle generation method provided by the present invention includes:

[0064] Step S101: Obtain the desired duty cycle and the previous cycle duty cycle of multiple wheel brake hydraulic valves respectively;

[0065] Step S102: Based on the desired duty cycle and the duty cycle of the previous cycle, determine the dynamic percentage, dynamic difference percentage, duty cycle increase speed control coefficient, and duty cycle decrease speed control coefficient for multiple wheel brake hydraulic valves respectively.

[0066] Step S103: Obtain the maximum increase and maximum decrease of the duty cycle for multiple wheel brake hydraulic valves respectively;

[0067] Step S104: Based on the maximum increase in duty cycle, the maximum decrease in duty cycle, and the desired duty cycle, determine the duty cycle increase limit and the duty cycle decrease limit.

[0068] Step S105: Determine the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple based on the duty cycle increase ratio limit, the duty cycle decrease ratio limit, and the dynamic difference percentage;

[0069] Step S106: Based on the duty cycle increase ratio multiple, duty cycle decrease ratio multiple, duty cycle increase speed control coefficient and duty cycle decrease speed control coefficient, determine the duty cycle increase dynamic percentage control coefficient and duty cycle decrease dynamic percentage control coefficient for multiple wheel brake hydraulic valves respectively, and determine the smaller value among the duty cycle increase dynamic percentage control coefficient and duty cycle decrease dynamic percentage control coefficient as the percentage adjustment optimization coefficient;

[0070] Step S107: Adjust the optimization coefficient and dynamic difference percentage according to the percentage, and determine the dynamic percentage to be executed;

[0071] Step S108: Generate the dynamic duty cycle of multiple wheel brake hydraulic valves in the current cycle based on the execution dynamic percentage, dynamic percentage, expected duty cycle and the previous cycle duty cycle.

[0072] In this embodiment, firstly, the desired duty cycle and the previous cycle duty cycle of multiple wheel brake hydraulic valves are obtained respectively. Based on the desired duty cycle and the previous cycle duty cycle, the dynamic percentage, dynamic difference percentage, duty cycle increase rate control coefficient, and duty cycle decrease rate control coefficient of multiple wheel brake hydraulic valves are determined respectively. Then, the maximum duty cycle increase value and the maximum duty cycle decrease value of multiple wheel brake hydraulic valves are obtained respectively. Then, based on the maximum duty cycle increase value, the maximum duty cycle decrease value, and the desired duty cycle, the duty cycle increase ratio limit value and the duty cycle decrease ratio limit value are determined. Finally, based on the duty cycle increase ratio limit value, the duty cycle decrease ratio limit value, and the dynamic difference percentage, the duty cycle increase ratio multiple and the duty cycle... The duty cycle is decreased by a multiple; next, based on the duty cycle increase multiple, duty cycle decrease multiple, duty cycle increase speed control coefficient, and duty cycle decrease speed control coefficient, the duty cycle increase dynamic percentage control coefficient and duty cycle decrease dynamic percentage control coefficient for multiple wheel brake hydraulic valves are determined respectively, and the smaller of the duty cycle increase dynamic percentage control coefficient and duty cycle decrease dynamic percentage control coefficient is determined as the percentage adjustment optimization coefficient; further, based on the percentage adjustment optimization coefficient and the dynamic difference percentage, the execution dynamic percentage is determined; finally, based on the execution dynamic percentage, dynamic percentage, desired duty cycle, and the duty cycle of the previous cycle, the dynamic duty cycle of multiple wheel brake hydraulic valves in the current cycle is generated.

[0073] In this embodiment, by performing restrictive calculations on the maximum increase and decrease of the duty cycle of multiple wheel brake hydraulic valves, the duty cycle increase ratio and duty cycle decrease ratio are determined to define the limits on duty cycle changes. Next, based on the duty cycle increase ratio, duty cycle decrease ratio, duty cycle increase rate control coefficient, and duty cycle decrease rate control coefficient, the percentage adjustment optimization coefficient for adjusting each wheel brake hydraulic valve is determined. Finally, based on the percentage adjustment optimization coefficient and the dynamic difference percentage, the execution dynamic percentage is determined, thereby enabling real-time determination of the dynamic duty cycle of multiple wheel brake hydraulic valves. This achieves high-precision control of the smooth change of the vehicle hydraulic valve duty cycle to the desired duty cycle, effectively ensuring vehicle stability.

[0074] As a preferred embodiment, in step S101, since the operating state of each wheel cannot be guaranteed to be completely consistent during the operation of the vehicle, the expected duty cycle and the duty cycle of the previous cycle corresponding to different wheels may not be the same. Therefore, for each wheel, it is necessary to obtain the expected duty cycle and the duty cycle of the previous cycle in groups to avoid data disorder.

[0075] In a preferred embodiment, in step S102, to determine the dynamic percentage, dynamic difference percentage, duty cycle increase / decrease speed control coefficient, and duty cycle decrease / decrease speed control coefficient of multiple wheel brake hydraulic valves based on the desired duty cycle and the duty cycle of the previous cycle, as follows: Figure 2 As shown, Figure 2 A flowchart illustrating an embodiment of the present invention for determining dynamic percentage, dynamic difference percentage, duty cycle increase rate control coefficient, and duty cycle decrease rate control coefficient includes:

[0076] Step S121: Based on the desired duty cycle and the duty cycle of the previous cycle, determine the dynamic percentage of multiple wheel brake hydraulic valves according to the dynamic percentage calculation formula.

[0077] Step S122: Determine the dynamic difference percentage of multiple wheel brake hydraulic valves based on the dynamic percentage and the dynamic difference percentage calculation formula;

[0078] Step S123: Based on the desired duty cycle and the duty cycle of the previous cycle, and using the calculation formulas for the duty cycle increase speed control coefficient and the duty cycle decrease speed control coefficient, determine the duty cycle increase speed control coefficient and the duty cycle decrease speed control coefficient for multiple wheel brake hydraulic valves respectively.

[0079] The formula for calculating the dynamic percentage is as follows:

[0080]

[0081] The formula for calculating the percentage of dynamic difference is:

[0082] Δrp(i) = |100% - rp(i)|

[0083] The formulas for calculating the duty cycle increase / decrease rate control coefficient and the duty cycle decrease / decrease rate control coefficient are as follows:

[0084]

[0085] Where i represents the number of the multiple wheel brake hydraulic valves, rp(i) represents the dynamic percentage, and r(k-1) represents the value of the valve. i r represents the duty cycle of the previous cycle. i Let b2(i) be the expected duty cycle, Δrp(i) be the dynamic difference percentage, and b2(i) be the value of b2(i). up To add a speed control coefficient to the duty cycle, b2(i) down The speed control coefficient is used to reduce the duty cycle.

[0086] In this embodiment, by analyzing and transforming the expected duty cycle and the previous cycle duty cycle, the state of multiple wheel brake hydraulic valves in the previous cycle and their corresponding data information are effectively analyzed.

[0087] In one specific embodiment, r(k-1) i The initial value is 0, i.e., r(0). i =0.

[0088] In one specific embodiment, when the vehicle has 4 wheels and all r i ≥r(k-1) i hour, It refers to the r of 4 wheels i -r(k-1) i The sum of the differences is not elaborated here; just follow the formula to calculate.

[0089] In a preferred embodiment, in step S103, in order to obtain the maximum value of the duty cycle increase and the maximum value of the duty cycle decrease for multiple wheel brake hydraulic valves respectively, such as Figure 3 As shown, Figure 3 A flowchart illustrating an embodiment of obtaining the maximum increase and maximum decrease of the duty cycle provided by the present invention includes:

[0090] Step S131: Obtain the maximum duty cycle increment and maximum duty cycle decrement of multiple wheel brake hydraulic valves, as well as the vehicle task execution cycle;

[0091] Step S132: Based on the maximum duty cycle increment, the maximum duty cycle decrement, and the vehicle task execution cycle, determine the maximum duty cycle increment and the maximum duty cycle decrement respectively using the calculation formulas for the maximum duty cycle increment and the maximum duty cycle decrement.

[0092] The formulas for calculating the maximum increase and decrease of the duty cycle are as follows:

[0093]

[0094] Where, Δr(i) upmax To increase the duty cycle to its maximum value, Δr(i) downmax To minimize the duty cycle, Δr(i) upmaxone Δr(i) represents the maximum increment of the duty cycle. downmaxone The duty cycle is the maximum reduction, and Δt is the vehicle task execution cycle.

[0095] It should be noted that Δr(i) upmaxone Δr(i) downmaxone These represent the maximum allowable increase or decrease in the duty cycle of the hydraulic line containing the i-th brake hydraulic valve per unit time. If the allowable duty cycle change of the i-th brake hydraulic valve and its hydraulic line exceeds this value, the drastic change in the amount of oil may lead to damage to the brake hydraulic valve and its hydraulic line, and a reduction in their service life.

[0096] The vehicle task execution cycle can be set according to actual needs, and it can be adaptively adjusted for different vehicle systems. For a specific vehicle, when the vehicle task execution cycle is determined, the maximum increment and maximum decrement of the duty cycle of each wheel brake hydraulic valve are uniquely determined.

[0097] In this embodiment, the maximum increase and maximum decrease of the duty cycle are determined by the calculation formulas for the maximum increase and maximum decrease of the duty cycle, respectively, which provides the basis for subsequent duty cycle adjustments and effectively ensures the stability of the adjusted duty cycle.

[0098] In a preferred embodiment, in step S104, to determine the duty cycle increase ratio limit and the duty cycle decrease ratio limit based on the maximum duty cycle increase, the maximum duty cycle decrease, and the desired duty cycle, specific calculation formulas for the duty cycle increase ratio limit and the duty cycle decrease ratio limit are proposed. These formulas are as follows:

[0099]

[0100] Where, Δrp(i) upmax To add a ratio limit value to the duty cycle, Δrp(i) downmax Reduce the duty cycle ratio limit value.

[0101] In a preferred embodiment, in step S105, to determine the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple based on the duty cycle increase ratio limit value, the duty cycle decrease ratio limit value, and the dynamic difference percentage, a specific calculation formula for the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple is proposed. The calculation formulas for the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple are as follows:

[0102]

[0103] Where, b1(i) upmax To increase the duty cycle by a factor of b1(i) downmax The duty cycle is reduced by a factor of 1.

[0104] In a preferred embodiment, in step S106, based on obtaining the duty cycle increase rate control coefficient, the duty cycle decrease rate control coefficient, the duty cycle increase ratio multiple, and the duty cycle decrease ratio multiple, in order to determine the duty cycle decrease dynamic percentage control coefficient, a specific calculation formula for the duty cycle increase dynamic percentage control coefficient and the duty cycle decrease dynamic percentage control coefficient is proposed. The calculation formulas for the duty cycle increase dynamic percentage control coefficient and the duty cycle decrease dynamic percentage control coefficient are as follows:

[0105]

[0106] The percentage adjustment optimization coefficient is:

[0107]

[0108] Where, b(i) up Add a dynamic percentage control factor, b(i), to the duty cycle. down To reduce the duty cycle, the dynamic percentage control coefficient, b2(i) up To add a speed control coefficient to the duty cycle, b2(i) down To reduce the duty cycle, the speed control coefficient, b min Adjust the optimization coefficients as a percentage.

[0109] In a preferred embodiment, in step S107, in order to determine the execution dynamic percentage by adjusting the optimization coefficient and the dynamic difference percentage according to the percentage, an execution dynamic percentage calculation formula is proposed, wherein the execution dynamic percentage calculation formula is:

[0110] Δrp1(i)=Δrp(i)*b min

[0111] Where Δrp1(i) represents the percentage of dynamic execution.

[0112] In a preferred embodiment, in step S108, after obtaining the dynamic percentage, a dynamic duty cycle calculation formula is proposed to obtain the accurate dynamic duty cycle of the multiple wheel brake hydraulic valves. The dynamic duty cycle calculation formula is as follows:

[0113]

[0114] Where, r(k) i This refers to the dynamic duty cycle.

[0115] By employing the above method, the maximum increase and decrease values ​​of the duty cycle for multiple wheel brake hydraulic valves are calculated with constraints to determine the duty cycle increase and decrease ratios, thus defining the limits on duty cycle variation. Next, based on these ratios, along with the duty cycle increase / decrease control coefficients and the duty cycle decrease / increase control coefficients, a percentage adjustment optimization coefficient for each wheel brake hydraulic valve is determined. Finally, based on the percentage adjustment optimization coefficient and the dynamic difference percentage, the execution dynamic percentage is determined, thereby enabling real-time determination of the dynamic duty cycle of multiple wheel brake hydraulic valves. This allows for high-precision control of the vehicle's hydraulic valves, ensuring a smooth change in duty cycle to the desired level and effectively guaranteeing vehicle stability.

[0116] Furthermore, to verify the feasibility of the above method, this embodiment performs a reverse inference. First, the change in the dynamic duty cycle of the brake hydraulic valve in adjacent cycles is:

[0117] Δr(k) i =r(k) i -r(k-1) i

[0118] Where, Δr(k) i This represents the change in dynamic duty cycle between adjacent periods.

[0119] Based on the relationship between the above formulas, we can conclude that:

[0120]

[0121] Furthermore,

[0122]

[0123] By simplification, we can obtain:

[0124]

[0125] Therefore, we obtain: |Δr(k) i |=r i *Δrp1(i)

[0126] Through the above methods, we can conclude that:

[0127] |Δr(k) i |=r i *Δrp(i)*b min

[0128]

[0129] Combination We can obtain:

[0130]

[0131] By simplification, we can obtain:

[0132]

[0133] And because:

[0134] The result shows that the change in the dynamic duty cycle of the brake hydraulic valve in adjacent time periods is less than or equal to the maximum increase in the duty cycle of the brake hydraulic valve during its task execution time period, and also less than or equal to the maximum decrease in the duty cycle of the brake hydraulic valve during its task execution time period. This avoids the risk of damage to the brake hydraulic valve and brake lines caused by drastic changes in the duty cycle of the brake hydraulic valve, thereby improving the durability and reliability of the vehicle.

[0135] Furthermore, the dynamic duty cycle of each brake hydraulic valve in the previous cycle is updated to its current dynamic duty cycle, i.e., r(k-1). i =r(k) i .

[0136] The time required for each brake hydraulic valve to change from the dynamic duty cycle of the previous cycle to the current dynamic duty cycle is:

[0137]

[0138] Among them, time i The time required for the duty cycle of the i-th brake hydraulic valve to change to the current dynamic duty cycle.

[0139] By substituting the formula, we can see that:

[0140]

[0141]

[0142]

[0143] Finally, through simplification, we can obtain:

[0144]

[0145] The conclusion is that the time required for all brake hydraulic valves to change from the dynamic duty cycle of the previous cycle to the desired duty cycle is equal. In other words, all brake hydraulic valves of the vehicle reach their desired duty cycles simultaneously, thereby ensuring that the braking torque of each wheel reaches the set value at the same time. This avoids inconsistent dynamic changes in the duty cycle of the brake hydraulic valves, which could lead to significant differences in the braking torque of each wheel and thus induce instability in the vehicle's braking process.

[0146] The present invention also provides an in-vehicle device, comprising: a processor and a memory; the memory storing a computer-readable program executable by the processor;

[0147] When the processor executes a computer-readable program, it implements the steps in the vehicle hydraulic valve duty cycle generation method described above.

[0148] The present invention also provides a vehicle including the vehicle-mounted equipment as described above.

[0149] In summary, the above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for generating the duty cycle of a vehicle hydraulic valve, applied to multi-wheeled vehicles, characterized in that, include: Obtain the desired duty cycle and the previous cycle duty cycle of multiple wheel brake hydraulic valves respectively; Based on the desired duty cycle and the previous cycle duty cycle, determine the dynamic percentage, dynamic difference percentage, duty cycle increase speed control coefficient, and duty cycle decrease speed control coefficient of the multiple wheel brake hydraulic valves respectively. The maximum increase and the maximum decrease in duty cycle of the plurality of wheel brake hydraulic valves are obtained respectively; Based on the maximum increase in duty cycle, the maximum decrease in duty cycle, and the desired duty cycle, determine the duty cycle increase ratio limit and the duty cycle decrease ratio limit. The duty cycle increase ratio limit, the duty cycle decrease ratio limit, and the dynamic difference percentage are used to determine the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple. Based on the duty cycle increase ratio, the duty cycle decrease ratio, the duty cycle increase speed control coefficient, and the duty cycle decrease speed control coefficient, the duty cycle increase dynamic percentage control coefficient and the duty cycle decrease dynamic percentage control coefficient of the plurality of wheel brake hydraulic valves are determined respectively, and the smaller value of the duty cycle increase dynamic percentage control coefficient and the duty cycle decrease dynamic percentage control coefficient is determined as the percentage adjustment optimization coefficient; The dynamic percentage to be executed is determined based on the adjusted optimization coefficient and the dynamic difference percentage. The dynamic duty cycle of the plurality of wheel brake hydraulic valves in the current cycle is generated based on the execution dynamic percentage, the dynamic percentage, the desired duty cycle, and the duty cycle of the previous cycle.

2. The method for generating the duty cycle of a vehicle hydraulic valve according to claim 1, characterized in that, The step of determining the dynamic percentage, dynamic difference percentage, duty cycle increase rate control coefficient, and duty cycle decrease rate control coefficient of the plurality of wheel brake hydraulic valves based on the desired duty cycle and the duty cycle of the previous cycle includes: Based on the desired duty cycle and the previous cycle duty cycle, the dynamic percentage of the plurality of wheel brake hydraulic valves is determined using the dynamic percentage calculation formula. Based on the dynamic percentage, and using the dynamic difference percentage calculation formula, the dynamic difference percentage of the plurality of wheel brake hydraulic valves is determined; Based on the desired duty cycle and the previous cycle duty cycle, and using the calculation formulas for the duty cycle increase speed control coefficient and the duty cycle decrease speed control coefficient, the duty cycle increase speed control coefficient and the duty cycle decrease speed control coefficient of the multiple wheel brake hydraulic valves are determined respectively. The formula for calculating the dynamic percentage is as follows: The formula for calculating the dynamic difference percentage is: Δrp(i) = |100% - rp(i)| The formulas for calculating the duty cycle increase / decrease rate control coefficient and the duty cycle decrease / decrease rate control coefficient are as follows: Where i is the number of the plurality of wheel brake hydraulic valves, rp(i) is the dynamic percentage, and r(k-1) is the number of the plurality of wheel brake hydraulic valves. i r is the duty cycle of the previous cycle. i Let b2(i) be the expected duty cycle, Δrp(i) be the dynamic difference percentage, and b2(i) be the dynamic difference percentage. up Add a speed control coefficient, b2(i), to the duty cycle. down The duty cycle reduction speed control coefficient is used.

3. The method for generating the duty cycle of a vehicle hydraulic valve according to claim 2, characterized in that, The step of obtaining the maximum increase and maximum decrease of the duty cycle of the plurality of wheel brake hydraulic valves includes: The maximum duty cycle increment and maximum duty cycle decrement of the plurality of wheel brake hydraulic valves, as well as the vehicle task execution cycle, are obtained respectively. Based on the maximum duty cycle increment, the maximum duty cycle decrement, and the vehicle task execution cycle, the maximum duty cycle increment and the maximum duty cycle decrement are determined using the calculation formulas for the maximum duty cycle increment and the maximum duty cycle decrement. The formulas for calculating the maximum increase and maximum decrease of the duty cycle are as follows: Where, Δr(i) upmax Increase the duty cycle by a maximum value, Δr(i). downmax The maximum decrease in the duty cycle is Δr(i). upmaxone Let Δr(i) be the maximum increment of the duty cycle. downmaxone The duty cycle is the maximum reduction, and Δt is the vehicle task execution cycle.

4. The method for generating the duty cycle of a vehicle hydraulic valve according to claim 3, characterized in that, The step of determining the duty cycle increase limit and the duty cycle decrease limit based on the maximum duty cycle increase, the maximum duty cycle decrease, and the desired duty cycle includes: Based on the maximum duty cycle increase, the maximum duty cycle decrease, and the desired duty cycle, and using the calculation formulas for the duty cycle increase ratio limit and the duty cycle decrease ratio limit, the duty cycle increase ratio limit and the duty cycle decrease ratio limit are determined respectively. The formulas for calculating the duty cycle increase ratio limit and the duty cycle decrease ratio limit are as follows: Where, Δrp(i) upmax Add a ratio limit value, Δrp(i), to the duty cycle. downmax The duty cycle is reduced by a ratio limit value.

5. The method for generating the duty cycle of a vehicle hydraulic valve according to claim 4, characterized in that, The step of determining the duty cycle increase ratio multiple and the duty cycle decrease ratio multiple based on the duty cycle increase ratio limit value, the duty cycle decrease ratio limit value, and the dynamic difference percentage includes: Based on the duty cycle increase ratio limit, the duty cycle decrease ratio limit, and the dynamic difference percentage, the duty cycle increase ratio and duty cycle decrease ratio are determined according to the calculation formulas for the duty cycle increase ratio and duty cycle decrease ratio. The formulas for calculating the duty cycle increase ratio and the duty cycle decrease ratio are as follows: Where, b1(i) upmax Increase the duty cycle by a ratio factor, b1(i) downmax The duty cycle is reduced by a factor of 1.

6. The method for generating the duty cycle of a vehicle hydraulic valve according to claim 5, characterized in that, The process involves determining, based on the duty cycle increase ratio, the duty cycle decrease ratio, the duty cycle increase rate control coefficient, and the duty cycle decrease rate control coefficient, the dynamic percentage control coefficient for duty cycle increase and decrease of the plurality of wheel brake hydraulic valves, respectively, and determining the smaller of the dynamic percentage control coefficient for duty cycle increase and decrease as the percentage adjustment optimization coefficient, including: Based on the duty cycle increase ratio multiple, the duty cycle decrease ratio multiple, the duty cycle increase rate control coefficient, and the duty cycle decrease rate control coefficient, and based on the calculation formulas for the duty cycle increase dynamic percentage control coefficient and the duty cycle decrease dynamic percentage control coefficient, the duty cycle decrease dynamic percentage control coefficient is determined. The calculation formulas for the duty cycle increase dynamic percentage control coefficient and the duty cycle decrease dynamic percentage control coefficient are as follows: The percentage adjustment optimization coefficient is: Where, b(i) up Add a dynamic percentage control coefficient, b(i), to the duty cycle. down The dynamic percentage control coefficient for reducing the duty cycle is b2(i). up Add a speed control coefficient, b2(i), to the duty cycle. down b is the control coefficient for the rate of decrease of the duty cycle. min Adjust the optimization coefficient for the percentage.

7. The method for generating the duty cycle of a vehicle hydraulic valve according to claim 6, characterized in that, The step of adjusting the optimization coefficient and the dynamic difference percentage based on the percentage to determine the execution dynamic percentage includes: Based on the percentage adjustment optimization coefficient and the dynamic difference percentage, the execution dynamic percentage is determined according to the execution dynamic percentage calculation formula; The formula for calculating the dynamic percentage is as follows: Δrp1(i)=Δrp(i)*b min Wherein, Δrp1(i) is the execution dynamic percentage.

8. The method for generating the duty cycle of a vehicle hydraulic valve according to claim 7, characterized in that, The step of generating the dynamic duty cycle of the plurality of wheel brake hydraulic valves in the current cycle based on the execution dynamic percentage, the dynamic percentage, the desired duty cycle, and the previous cycle duty cycle includes: Based on the execution dynamic percentage, the dynamic percentage, the expected duty cycle, and the previous cycle duty cycle, the dynamic duty cycle of the multiple wheel brake hydraulic valves in the current cycle is generated according to the dynamic duty cycle calculation formula. The formula for calculating the dynamic duty cycle is as follows: Where, r(k) i The dynamic duty cycle is mentioned above.

9. A vehicle-mounted device, characterized in that, include: Processor and memory; The memory stores a computer-readable program that can be executed by the processor; When the processor executes the computer-readable program, it implements the steps in the vehicle hydraulic valve duty cycle generation method as described in any one of claims 1-8.

10. A vehicle, characterized in that, Including the vehicle-mounted equipment as described in claim 9.

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