Vehicle dynamics vector unification control method and system

Abstract

The application discloses a vehicle dynamics vector unified control method, in a vehicle with a driving system with high-precision fast torque response capability, vehicle longitudinal motion control, yaw attitude control and side wind field disturbance compensation are multi-dimensional distribution problems of a same vector force source in a same constraint space, total output torque T and differential torque ΔT (including a side wind compensation component ΔT_wind) should be taken as joint decision variables of a same optimization problem, and are synchronously solved under a same target function and a same tire adhesion limit constraint condition, and are determined at one time, and are unified output from a same power path by the driving system, and the braking system is only used as an auxiliary means to intervene when the output capability of the driving system is insufficient to realize the control target.

Description

Technical Field

[0001] This invention relates to the field of vehicle dynamics control technology, and more particularly to a unified vector control method and system for vehicle dynamics with the drive system as the unified vector actuator. This invention is applicable to pure electric vehicles, hybrid vehicles, range-extended vehicles, drive-by-wire chassis vehicles, and autonomous vehicles (Levels L2-L4). Background Technology

[0002] The existing vehicle chassis control system is based on the following implicit assumption: longitudinal motion control and yaw attitude control are independent sub-problems that should be solved separately by independent execution systems, and then arbitrated through a coordination layer, such as... Figure 8 As shown. The hydraulic braking system is responsible for deceleration, ESP (Electronic Stability Program) intervenes in yaw through unilateral braking force differential, and the drive system is dedicated to power output. The three systems are coordinated and arbitrated by a controller.

[0003] While existing torque vectoring techniques introduce yaw intervention capabilities into the drive system, their total output torque T and differential torque ΔT originate from two independent decision-making processes: driver demand determines T, and the stability controller independently determines ΔT, with the two being superimposed as the output. T and ΔT are not joint decision variables in the same optimization problem and are not solved simultaneously under the same objective function and constraints. Furthermore, the yaw disturbance torque generated by lateral wind speed has not been incorporated into any existing scheme for a unified closed-loop solution involving T and ΔT.

[0004] The root cause of the aforementioned limitations lies in the flawed problem definition itself: the longitudinal and lateral forces borne by the tire always share the same adhesion boundary constraint, placing T and ΔT in two independent decision-making processes. Mathematically, it is impossible to obtain a coordinated optimization solution under a unified adhesion constraint. Specific defects are manifested in the following ways: First, the superimposed structure of independent decisions for T and ΔT leads to control command competition under high-dynamic conditions, preventing the utilization of adhesion resources from achieving a coordinated optimization result under unified constraints. Second, the braking system, as the main actuator for yaw control, achieves attitude intervention by consuming kinetic energy, which is inherently inefficient. Third, the yaw disturbance torque caused by lateral wind speed has never been included in any existing system for joint solution with T and ΔT in a unified closed-loop process, and remains in a state of passive correction.

[0005] To address one of the aforementioned problems, this application provides a unified vector control method and system for vehicle dynamics. Summary of the Invention

[0006] The purpose of this invention is to provide a unified vector control method and system for vehicle dynamics. In the field of vehicle dynamics, it fully defines and engineered a control architecture that "uses T and ΔT as joint decision variables for the same optimization problem, solves synchronously and determines them at once in a unified constraint space, and outputs them uniformly from the same power path by the drive system". It incorporates longitudinal motion control, yaw attitude control and lateral wind disturbance compensation into the same joint decision framework. It solves the fundamental defects of existing technologies, such as the superposition of independent decisions of T and ΔT, passive correction of lateral wind disturbance, and independent competition of constraint resources among multiple actuators.

[0007] To achieve the above objectives, this invention establishes the following control theory framework: In vehicles with drive systems possessing high-precision and rapid torque response capabilities, longitudinal motion control, yaw attitude control, and lateral wind disturbance compensation are multidimensional allocation problems involving the same vector force source within the same constraint space. The total output torque T and differential torque ΔT (including the lateral wind compensation component ΔT_wind) should be used as joint decision variables for the same optimization problem, solved synchronously and determined at once under the same objective function and the same tire adhesion limit constraints, and uniformly output by the drive system from the same power path; the braking system only intervenes as an auxiliary means when the output capability of the drive system is insufficient to achieve the aforementioned control objectives.

[0008] The framework has a mathematical isomorphic correspondence with rocket thrust vector control: total thrust vector ←→ total output torque T of the drive system; thrust vector directional component ←→ differential torque ΔT of the left and right drive wheels; atmospheric friction coefficient constraint ←→ tire adhesion coefficient constraint; wind field yaw disturbance ←→ lateral wind field yaw disturbance torque; unified solution of the joint decision variables of the two ←→ unified solution of the joint decision variables of T and ΔT (including the crosswind compensation component ΔT_wind).

[0009] Compared with the prior art, the beneficial effects of the present invention are: 1. Joint Decision Variable Framework – Correct Definition of Control Problem: This invention upgrades T and ΔT from an independent decision superposition structure to joint decision variables of the same optimization problem. They are solved simultaneously and determined at once under the same objective function and the same constraints. This is a fundamental redefinition of the vehicle dynamics control problem at the mathematical structure level, and it is the core technical feature that distinguishes this invention from all existing torque vector distribution schemes.

[0010] 2. Crosswind active compensation is incorporated into three-dimensional joint solution: This invention incorporates the crosswind compensation differential torque ΔT_wind into the three-dimensional joint decision variable (T, ΔT_yaw, ΔT_wind) framework, and solves it simultaneously under the same constraints to determine it at once. This is a control dimension that is not covered by existing ESP, torque vector distribution, integrated chassis control and domain controller solutions.

[0011] 3. Eliminate multi-loop constraint competition: T and ΔT (including ΔT_wind) are solved at once as joint decision variables under unified constraints, which completely eliminates the fundamental defect in the existing two-step decision superposition structure where constraint resources are repeatedly competed for by independent decision processes, and the attached utilization efficiency reaches the coordinated optimization result under unified constraints.

[0012] 4. Full configuration coverage: The joint decision variable framework of the present invention is applicable to all mainstream drive configurations such as single motor + electronic differential lock (hereinafter referred to as eLSD), front and rear axle dual motors, and four-wheel independent motors, and extends to cover L2-L4 level autonomous driving scenarios through the predictive control of claim 8. Attached Figure Description

[0013] Figure 1 This invention provides a unified solution control structure diagram for joint decision variables. Figure 2 This is the control flowchart of the present invention; Figure 3 This is a diagram of the active compensation control link for lateral wind field disturbances according to the present invention. Figure 4 The following are schematic diagrams of the three driving configurations of the present invention. Figure 1 (Single motor + eLSD configuration); Figure 5 The following are schematic diagrams of the three driving configurations of the present invention. Figure 2 (Dual electric mechanism type on front and rear axles); Figure 6 The following are schematic diagrams of the three driving configurations of the present invention. Figure 3 (Four-wheel independent electric mechanism configuration); Figure 7 This is a logic diagram for determining the braking assistance intervention of the present invention; Figure 8 This is a diagram of the existing two-step independent decision control structure. Detailed Implementation

[0014] In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0015] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "fixed," "installed," "connected," "set," etc., should be interpreted broadly. For example, when an element is said to be "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is said to be "installed" on another element, it can be directly installed on the other element or there may be an intervening element. When an element is said to be "connected" to another element, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within the two elements.

[0016] Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] The fundamental premise of this invention is that the correct problem form for vehicle dynamics control is a multi-dimensional real-time allocation problem of a single vector force source within a unified constraint space, rather than a discrete coordination problem involving multiple actuators. This invention uses the drive system as a unified vector actuator, treating the total output torque T (longitudinal control), yaw control differential torque ΔT_yaw (yaw control), and crosswind compensation differential torque ΔT_wind (crosswind compensation) as joint decision variables for the same optimization problem. These variables are solved simultaneously and determined in one step under unified tire adhesion limit constraints, and output uniformly from the same power path by the drive system. The braking system intervenes only as needed when the drive system's output capability is insufficient. This invention does not limit specific optimization algorithms, sensor configurations, or drive configurations.

[0019] The essential difference between "joint solution" and "independent solution"—an explanation of forced coupling To avoid ambiguity in distinguishing between "joint solution" and "independent solution," this invention clarifies their essential difference: In the joint decision variables, the coupling relationship between T and ΔT (including ΔT_wind) is manifested in the fact that a change in the value of any variable will simultaneously affect the feasible region boundary of the other variable under the unified tire adhesion limit constraint. In other words, in the joint solution structure of this invention, the feasible region of T and the feasible region of ΔT are always interdependent and inseparably determined together during the solution process, constituting coupled variables on the same constrained manifold.

[0020] In contrast, in the existing independent solution structures (including a two-step decision structure that superimposes driver demand determination T and stability controller independent determination ΔT, and an iterative structure that first sets initial values ​​for T or ΔT and then fine-tunes the initial values ​​through an optimizer), the feasible regions of T and ΔT are set independently at the initial stage of the solution. There is no forced coupling relationship where the feasible regions of the two variables shrink or expand in real time as the other takes a value. Even if an iterative correction step is introduced later, as long as there is a step of setting an initial value for either variable, the initial value constitutes an asymmetric constraint on the feasible region of the other variable, which does not satisfy the technical feature described in step S3 of this invention that "the feasible regions of T and ΔT are mutually coupled under the same tire adhesion limit constraint condition".

[0021] Therefore, any existing technical solution that adopts the "preset initial value + optimizer fine-tuning" structure does not fall into the equivalent alternative solution that does not go through the "two-step decision-making process of solving independently first and then superimposing" because it is essentially still using the preset value of one variable as the boundary condition for solving another variable, rather than the forced coupling of the feasible regions of the two.

[0022] Symbol definition To avoid ambiguity, the meanings of each symbol in this invention are as follows: T: Total output torque of the vehicle (scalar), which is provided by a single motor in a single-motor configuration (can be positive or negative, with positive values ​​corresponding to driving and negative values ​​corresponding to regenerative braking), and is the sum of the torques of each axle / wheel in a multi-motor configuration; ΔT: Differential torque (scalar), representing the difference in torque between the left and right drive wheels, which is decomposed into yaw control component ΔT_yaw and crosswind compensation component ΔT_wind in claim 2 and subsequent claims; ΔT_yaw: Yaw control differential torque, which is the yaw attitude control direction component after decomposition of the differential torque ΔT; ΔT_wind: Crosswind compensation differential torque, which is the compensation component of the differential torque ΔT used to counteract the yaw disturbance torque of the lateral wind field after decomposition; T_f: The total output torque at the wheel end of the front axle drive motor in the dual-motor mechanism of the front and rear axles, which satisfies T=T_f+T_r; T_r: The total output torque at the wheel end of the rear axle drive motor in the dual-motor mechanism of the front and rear axles, which satisfies T=T_f+T_r; T_L, T_R: Output torque of the left and right drive wheels, satisfying T_L=T / 2+ΔT_yaw+ΔT_wind, T_R=T / 2-ΔT_yaw-ΔT_wind; T_brake: The longitudinal braking torque provided by the hydraulic braking system (when the regenerative braking capacity of the drive system is insufficient to achieve the target deceleration, it is supplemented by the hydraulic braking system). F_zi: Vertical load of the i-th drive wheel, where i is the drive wheel number; F_zf, F_zr: Vertical loads on the front and rear axles, corresponding to i = front axle / rear axle in F_zi; F_zi_max: The maximum available resultant force boundary of the i-th driving wheel, F_zi_max=μ•F_zi; F_xi, F_yi: longitudinal force and lateral force of the i-th drive wheel; μ: Road surface adhesion coefficient; M_wind: The equivalent yaw disturbance moment generated by the lateral wind field; m: Vehicle mass; I_z: Vehicle yaw inertia; v: vehicle speed; B: drive wheel track width; r: tire rolling radius; ω_r: yaw rate; a_x: longitudinal acceleration.

[0023] Example 1 (Three-dimensional joint decision-making solution under high-speed lateral wind field disturbance, corresponding to claims 2 and 3) Operating parameters Vehicle speed v = 120 km / h; crosswind speed v_wind = 18 m / s (wind coming from the right); road surface adhesion coefficient μ = 0.85; vehicle mass m = 1800 kg; drive wheel track B = 1.6 m; tire rolling radius r = 0.33 m; wind-induced equivalent yaw disturbance moment M_wind = +800 N•m (right yaw tendency); current yaw rate ω_r = +0.03 rad / s (wind-induced initial yaw).

[0024] Joint solution process t=0ms: The sensing module collects v_wind=18m / s and ω_r=+0.03rad / s.

[0025] t=5ms: Unified constraint conditions are established - the vertical load on the front axle corresponds to F_zf_max=0.85×9800=8330N, and the load on the rear axle corresponds to F_zr_max=0.85×7800=6630N.

[0026] t=10ms: Three-dimensional joint decision objective—T=0 (maintain vehicle speed); ΔT_yaw=80N•m (correct ω_r deviation); differential torque compensation component ΔT_wind corresponds to approximately 165N•m (determined by the joint solution process and not used as a fixed formula constraint).

[0027] t=15ms: The three-dimensional joint decision variables (T, ΔT_yaw, ΔT_wind) are solved simultaneously under the same objective function and unified constraints. The total differential torque ΔT_yaw+ΔT_wind is about 245N•m. The constraint verification √(F_x²+F_y²)≤F_zr_max passes, and the drive output capability is sufficient to achieve the control objective. Braking does not intervene.

[0028] t=20ms: Uniform output for the same power path — T_L=T / 2+245≈+245N•m, T_R=T / 2-245≈-245N•m (T=0, total driving torque is zero, differential torque is equal to the target value of 245N•m).

[0029] Results: The three-dimensional target was completed synchronously in one go; the braking system operated at 0 bar throughout the entire process.

[0030] Note: In this embodiment, ΔT_wind = 165 N•m is greater than ΔT_yaw = 80 N•m, which reflects that the two have the same priority weight in resource competition and are coordinated and allocated according to their respective demand ratios (see claim 7), rather than being equal in value.

[0031] Example 2 (Single motor + eLSD emergency avoidance + crosswind combined condition, corresponding to claims 11 and 6) This embodiment distinguishes between operating conditions where regenerative braking can be covered and operating conditions requiring hydraulic braking intervention, eliminating the physical paradox of a single motor generating negative torque braking.

[0032] Vehicle parameters Front-wheel drive pure electric SUV; m=1800kg; B=1600mm; peak drive torque of single motor is 320N•m, peak regenerative braking torque is 140N•m (wheel end), response delay <8ms; maximum transferable torque of eLSD is 180N•m, delay <15ms; control cycle is 5ms.

[0033] Scenario A: Moderate deceleration avoidance condition (regenerative braking can cover this) Operating conditions: v=80km / h, obstacle 60m ahead, target deceleration -3m / s², and wind speed on the left 8m / s. The target braking torque corresponds to a regenerative braking requirement of approximately 480N•m (wheel end, equivalent to four wheels), with a single-wheel regenerative braking requirement of approximately 120N•m, which does not exceed the peak regenerative braking capacity of 140N•m for a single motor.

[0034] Joint solution: T is a negative value (regenerative braking), corresponding to the target deceleration; ΔT_yaw is the differential component required for right yaw avoidance; ΔT_wind is the compensation component required to counteract the yaw caused by left yaw; the three are jointly solved under unified constraints, and the eLSD transferable torque margin meets the requirements of ΔT_yaw + ΔT_wind.

[0035] Results: The drive system (motor regenerative braking + eLSD differential) independently completes the three-dimensional objectives of deceleration, obstacle avoidance, and crosswind compensation. The hydraulic braking system does not intervene throughout the process, the braking is 0 bar, and the energy recovery efficiency is about 85%.

[0036] Scenario B: Emergency avoidance situation (hydraulic braking intervention required) Operating conditions: v=100km / h, an obstacle suddenly appears 50m ahead, the target deceleration is -6m / s², and the wind speed on the left is 12m / s.

[0037] t=10ms: Joint decision target - the total braking torque requirement corresponding to the target deceleration of -6m / s² exceeds the peak regenerative braking torque of a single motor by 140N•m (exceeding the total available regenerative braking after wheel-end equivalent); ΔT_yaw: the differential torque corresponding to the yaw moment of 1200N•m when deflecting to the right to avoid the target; ΔT_wind: the compensation component corresponding to the wind-induced yaw moment of 600N•m when deflecting to the left.

[0038] t=15ms: Joint solution determination - According to claim 6 case (a), the upper limit of the regenerative braking power of the drive motor is insufficient to meet the T requirement corresponding to the target deceleration, and the output capacity of the drive system is insufficient to achieve the control target, triggering the hydraulic braking system to intervene as needed; the intervention amount is the difference between the target braking torque and the available regenerative braking torque of the motor, and the drive system simultaneously provides the differential torque components corresponding to ΔT_yaw and ΔT_wind with its remaining capacity.

[0039] t=20ms: Execution—The hydraulic braking system provides differential braking torque T_brake_assist (the intervention amount is determined by the control target achievement requirements according to claim 6); the drive system motor provides peak regenerative braking of 140 N•m and differential torque (ΔT_yaw+ΔT_wind) through eLSD, and the two together achieve the total deceleration target and yaw target.

[0040] Results: The longitudinal deceleration target was achieved by hydraulic braking (main) and motor regenerative braking (auxiliary), and the yaw attitude control (avoidance + crosswind compensation) was achieved independently by the drive system eLSD differential. No negative torque exceeding the regenerative braking capacity was generated by the motor throughout the process, which meets the judgment logic of step S6 of claim 1 and claim 6. There is no physically infeasible negative torque output.

[0041] Example 3 (Low adhesion road surface μ=0.25, insufficient drive output capability triggers braking assist, corresponding to claim 6) v=120km / h, emergency braking + yaw stabilization, μ=0.25. Joint solution results: T demand (the braking torque demand corresponding to the target deceleration) exceeds the upper limit of the regenerative braking capacity of the drive system and the adhesion boundary limit, causing the longitudinal force of each wheel to reach the F_zi_max boundary. The available margin ΔT_yaw is insufficient to generate the target synthetic yaw moment under unified constraints—the drive output capacity is insufficient to achieve the control target, triggering judgment conditions (a) and (b). The hydraulic braking system intervenes as needed to provide differential longitudinal braking force and yaw moment supplementation. The drive system continues to perform differential torque-dominated control within the remaining adhesion margin, with an energy recovery efficiency of approximately 82%.

[0042] Example 4 (Low-speed limit maneuvering and stationary turning, corresponding to claim 1) For speeds less than 5 km / h, a minimum turning radius is required. Joint decision variables: total driving torque T is zero or close to zero; ΔT_yaw is maximized; ΔT_wind = 0 (no crosswind). The joint solution maximizes ΔT_yaw under unified constraints. T_L and T_R are in opposite directions and have similar amplitudes, resulting in a net torque of zero or close to zero, achieving in-situ turning. The driving output capability is sufficient to achieve the control objective, and braking does not intervene.

[0043] Example 5 (Joint solution of a four-motor distributed architecture, corresponding to claim 13) Four independent motors for each wheel. The adhesion boundary of each wheel is established independently using a friction circle model or an equivalent approximation model, and the unified constraint conditions are jointly constituted by the constraints of the four wheels. The joint decision variable solution module uses the torque of each wheel (T_FL, T_FR, T_RL, T_RR) as the joint decision variable, and solves it simultaneously and determines it at once under the same objective function and unified constraints of the four wheels, without the need for arbitration at the coordination layer.

[0044] The essential difference from the existing four-motor scheme is that the existing scheme adopts a two-step decision-making structure of independent calculation and coordination arbitration for each wheel controller. The feasible domain of each wheel torque is set independently in the early stage of the solution, which does not meet the forced coupling requirement of "mutual coupling of feasible domains" mentioned in step S3.

[0045] Example 6 (Joint decision-making control of dual electric mechanism on front and rear axles, corresponding to claim 13) Configuration Description The dual-motor architecture (front and rear axles) is currently the most widely installed drive architecture in the new energy passenger vehicle market. This embodiment clarifies the technical meaning of "same power transmission path": the front and rear motors are uniformly scheduled by the domain controller; the front axle torque T_f and rear axle torque T_r are both determined and issued in one go by the same joint decision variable solution process; they share the same set of tire adhesion limit constraints, and there is no two-step decision-making process where the front and rear axle controllers make independent decisions and then superimpose them. T_f + T_r = T (total vehicle output torque); the difference between T_f and T_r generates yaw moment through wheelbase modulation, both of which are uniformly output from the drive system.

[0046] Vehicle parameters and uniform constraints A pure electric mid-size SUV with four-wheel drive and dual motors; m=1950kg; wheelbase L=2900mm; distance from center of gravity to front axle l_f=1250mm; distance from center of gravity to rear axle l_r=1650mm; peak wheel-end torque of the front motor 2200N•m; peak wheel-end torque of the rear motor 3200N•m; response delay of both front and rear motors <5ms; each axle is equipped with an open differential; domain controller operation cycle 5ms.

[0047] Front axle vertical load F_zf = 1950 × 9.8 × 1.65 / 2.9 ≈ 10886 N; rear axle vertical load F_zr = 1950 × 9.8 × 1.25 / 2.9 ≈ 8244 N; when μ = 0.85: F_zf_max ≈ 9253 N, F_zr_max ≈ 7007 N; unified constraint conditions: F_xf ≤ F_zf_max, F_xr ≤ F_zr_max.

[0048] Operating Condition 1: High-speed crosswind disturbance compensation (verification of claims 2 and 3) v = 120 km / h, right-side wind speed 16 m / s, M_wind = +720 N•m, ω_r = +0.02 rad / s. Joint decision objective: T_f + T_r = 800 N•m (maintain vehicle speed); total target yaw moment M_total (yaw correction + crosswind compensation) = -780 N•m. Joint solution result: T_f = 120 N•m, T_r = 680 N•m (total T = 800 N•m maintained, the difference between T_r and T_f generates a yaw moment of -780 N•m through wheelbase modulation). Constraint verification passed, braking not engaged, braking bar 0.

[0049] Operating Condition 2: Emergency Braking + Yaw Stabilization (Verification of Step S6 in Claim 1) v=100km / h, μ=0.75, longitudinal deceleration a_x=-7.5m / s², yaw correction torque M_yaw=-400N•m. Target total braking torque T_brake=m×|a_x|×r=1950×7.5×0.34≈4973N•m (at wheel end). Constraint verification: the front axle bears 40%, which is about 1989N•m, and the longitudinal force of a single wheel is about 2925N<F_zf_max=8165N; the rear axle bears 60%, which is about 2984N•m, and the longitudinal force of a single wheel is about 4388N<F_zr_max=6183N. The peak regenerative braking capacity of front and rear dual motors (2200N•m+3200N•m=5400N•m) is greater than the target total braking torque of 4973N•m, the constraint is satisfied. The drive system executes alone (dual-motor regenerative braking + front and rear axle torque difference), and the energy recovery efficiency is about 88%. If μ drops to 0.25: the adhesion boundary narrows, and the drive output capacity is insufficient to achieve the control target, the braking system intervenes as needed, which satisfies step S6 of claim 1.

[0050] Example 7 (autonomous driving predictive control composite working condition, corresponding to claim 8) Working condition parameters Level L3 autonomous driving; v=110km / h; lateral wind speed 14m / s (intermittent gust); road adhesion coefficient μ=0.35 (slippery road surface); the target trajectory is a high-speed ramp curve.

[0051] Joint solution process of predictive control Prediction domain N=20 time steps (5ms per step, prediction domain 100ms). Joint decision variable sequence: (T(k), ΔT_yaw(k), ΔT_wind(k)), k=0,1,...,19, which is solved by rolling optimization under unified constraint conditions.

[0052] t=0ms: current state acquisition, the wind field prediction module outputs the M_wind prediction sequence for the next 100ms; t=5ms: establishment of unified constraint conditions (based on the estimated minimum value of μ in the prediction domain, conservative constraint); t=10ms: the joint decision variable sequence of the prediction domain is solved by rolling optimization under unified constraint conditions, and the (T, ΔT_yaw, ΔT_wind) sequence from k=0 to k=19 is determined at one time; t=15ms: execute the control amount of the k=0 time step, and the drive system outputs uniformly from the same power path; t=20ms: the rolling window moves forward, the state is re-acquired, and the next solution cycle is entered.

[0053] Result Crosswind disturbances are pre-incorporated into the joint solution of the prediction domain before the arrival of gusts, resulting in a smooth vehicle yaw response; under low-adhesion road surfaces, the joint decision variables are coordinated and optimized within the constraints, and the output capability of the drive system is sufficient to achieve the control objective, without the intervention of the braking system; this embodiment demonstrates that the present invention, through the predictive control extension of claim 8, is applicable to L2-L4 autonomous driving scenarios and is the basic architecture for the next generation of autonomous driving chassis control.

[0054] The sensors, actuators, domain controllers and their supporting software involved in this invention are existing technologies or materials, and the relevant technical personnel can directly purchase or order them from the market according to the required product models and specifications.

[0055] The above description is merely a preferred embodiment of the present invention, and common knowledge regarding specific structures and characteristics in the solutions is not described in detail here. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above embodiments, and that the present invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this invention, based on the technical solutions and inventive concepts of the present invention, should be covered within the protection scope of this invention.

Claims

1. A unified vector control method for vehicle dynamics, characterized in that, Includes the following steps: Step S1: The drive system is used as a unified actuator for longitudinal motion control and yaw attitude control of the vehicle. The drive system physically has the ability to modulate the total output torque T of the vehicle and the differential torque ΔT between the left and right drive wheels. Step S2: Obtain vehicle dynamic state parameters and generate the target total output torque T required for longitudinal motion control and the target differential torque ΔT required for yaw attitude control; Step S3: The target total output torque T and the target differential torque ΔT are used as joint decision variables for the same optimization problem. They are solved simultaneously under the same objective function and the same tire adhesion limit constraint. The final values ​​of T and ΔT are determined at once by the joint solution process. The feasible regions of T and ΔT are coupled to each other under the same tire adhesion limit constraint, without going through a two-step decision process of solving independently and then superimposing. Step S4: Output the total output torque T and differential torque ΔT, which have been determined by joint solution, to the left and right drive wheels via the same power transmission path; Step S5: Based on real-time vehicle dynamic state feedback, the vehicle state parameters in the joint solution process are updated in real time, and T and ΔT are dynamically corrected to form closed-loop control. Step S6: The hydraulic braking system intervenes as an auxiliary means only when the output capacity of the drive system is insufficient to achieve the control objective.

2. The vehicle dynamics vector unified control method according to claim 1, characterized in that, Also includes: The differential torque ΔT described in step S3 is decomposed into a yaw control differential torque component ΔT_yaw and a crosswind compensation differential torque component ΔT_wind. This expands the joint solution in step S3 to a three-dimensional joint decision variable with (T, ΔT_yaw, ΔT_wind) as the same optimization problem. The solution is performed simultaneously under the same objective function and the same tire adhesion limit constraint. The final values ​​of T, ΔT_yaw, and ΔT_wind are determined once by the three-dimensional joint solution process. Real-time acquisition of lateral wind speed or equivalent lateral disturbance moment, and inclusion of lateral wind field disturbance compensation target as an independent control dimension at the same level as longitudinal motion target and yaw attitude target into the three-dimensional joint decision-making framework; ΔT_wind and ΔT_yaw have the same priority weight, both higher than T, but lower than the uniform tire adhesion limit constraint boundary; The resultant vector of the three-dimensional joint decision variables is constrained by the unified adhesion limit boundary, and the resultant vector of the longitudinal force and lateral force of each driving wheel does not exceed the adhesion boundary of that wheel; The hydraulic braking system intervenes as an auxiliary means only when the output capacity of the drive system is insufficient to achieve the three-dimensional joint control objective.

3. A unified vehicle dynamics vector control method according to claim 1 or 2, characterized in that, It also includes active compensation steps for lateral wind field disturbances: Obtain or estimate the lateral wind speed and the resulting equivalent yaw disturbance moment; Based on the equivalent yaw disturbance torque, a corresponding differential torque compensation component is generated; The differential torque compensation component, the active yaw control differential component, and the total output torque modulation are solved simultaneously as joint decision variables within the same unified tire adhesion limit constraint space. Based on the joint solution results, the differential torque compensation component is applied to the differential output of the left and right drive wheels in the direction of counteracting the yaw disturbance torque; The active compensation for lateral wind field disturbance forms a real-time closed loop, updates the estimated value of the equivalent yaw disturbance moment in real time, and dynamically corrects the joint solution input of the differential torque compensation component until the wind-induced yaw disturbance converges to the target range.

4. The vehicle dynamics vector unified control method according to claim 3, characterized in that, The lateral wind speed and equivalent yaw disturbance moment can be obtained or estimated through one of the following methods or their weighted fusion: (a) Direct measurement by vehicle-mounted wind speed sensor; (b) State observer estimation based on yaw rate, lateral acceleration, wheel speed and vehicle dynamics model; (c) Inverse calculation of equivalent disturbance torque based on the deviation between steering wheel input and actual yaw response.

5. The vehicle dynamics vector unified control method according to claim 1, characterized in that, The unified tire adhesion limit constraint condition is established by the following method: Real-time estimation of vertical load F_zi on each drive wheel and road adhesion coefficient μ; The maximum available resultant force boundary F_zi_max=μ•F_zi for each drive wheel is determined by using the friction circle model, the tire force ellipse model, or their equivalent approximation models. The solution of the joint decision variable (T, ΔT) is based on the unified constraint that the resultant vector of the longitudinal force F_xi and the lateral force F_yi of each driving wheel does not exceed F_zi_max, where i is the number of each driving wheel. The constraint is expressed as √(F_xi²+F_yi²)≤F_zi_max.

6. The vehicle dynamics vector unified control method according to claim 1, characterized in that, The determination that the output capability of the drive system is insufficient to achieve the control objective includes at least one of the following calculable scenarios: (a) The drive motor reaches the thermal power limit or the regenerative braking power limit, and the available torque limit is lower than the T requirement of the joint solution result; (b) Under the unified constraint conditions, the attachment boundary has been exhausted by the T demand, and the available margin of ΔT is insufficient to generate the target composite yaw moment; (c) The vehicle's dynamic response speed requirement exceeds the maximum torque change rate of the drive system; When any of the above conditions are met, the hydraulic braking system intervenes as an auxiliary means, and the amount of intervention is determined by the control objective requirements at that time.

7. The vehicle dynamics vector unified control method according to claim 2, characterized in that, When resource competition exists among the three-dimensional joint decision variables (T, ΔT_yaw, ΔT_wind) under unified constraints, they are coordinated according to the following priority: Unified attachment limit constraint boundary (highest, cannot be violated) > vehicle stability target > {ΔT_wind target and ΔT_yaw target have the same priority weight, and are coordinated and allocated according to their respective demand ratio} > trajectory tracking accuracy target > T target (lowest).

8. The vehicle dynamics vector unified control method according to claim 2, characterized in that, It also includes predictive control steps: The vehicle state (including the lateral wind field change prediction channel) is predicted for multiple future time steps based on the vehicle dynamics model. Based on the prediction results, (T, ΔT_yaw, ΔT_wind) is used as a sequence of joint decision variables in the prediction domain. Under unified constraints, rolling optimization is performed to achieve proactive prevention of crosswind disturbances. The predictive control steps are applicable to chassis dynamics control in L2-L4 level autonomous driving scenarios.

9. The vehicle dynamics vector unified control method according to claim 1, characterized in that, It also includes real-time estimation of road surface adhesion coefficient μ, tire vertical load F_zi, vehicle mass m, and yaw inertia I_z, which are used to dynamically update the unified constraints and correct the solution results of the joint decision variables.

10. The vehicle dynamics vector unified control method according to claim 1, characterized in that, Vehicle dynamic state parameters can be obtained through direct measurement, dynamic estimation, equivalent state quantity calculation, or indirect dynamic state characterization. Equivalent state quantities include yaw rate, lateral acceleration, wheel speed difference, vehicle body slip angle, estimated adhesion utilization rate, estimated lateral wind torque, or other parameter combinations that can characterize the multidimensional dynamic state of the vehicle. The acquisition method does not affect the protection scope of the joint solution process described in step S3 of claim 1.

11. A unified vector control method for vehicle dynamics according to claim 1 or 2, characterized in that, The drive system includes a single drive motor and an electronic differential lock. The electronic differential lock transfers torque between the left and right drive wheels by adjusting the clutch clamping force to achieve the differential torque component determined by the joint solution. The output torque of the left and right drive wheels is determined by a joint solution. The difference between the two is determined by the joint solution of ΔT_yaw and ΔT_wind. The achievable range of the difference is limited by the maximum transferable torque of the electronic differential lock and the current total output torque T. T, ΔT_yaw and ΔT_wind are all determined by a joint solution under unified constraints.

12. A unified vector control system for vehicle dynamics, characterized in that, include: The multi-dimensional state perception module collects vehicle dynamic state parameters and lateral wind speed or equivalent lateral disturbance torque in real time. The unified constraint condition establishment module establishes unified constraint conditions for the adhesion force boundaries of each drive wheel in real time based on the friction circle model, the tire force ellipse model, or their equivalent approximation models. The joint decision variable solving module uses the total output torque T, the yaw control differential torque ΔT_yaw, and the crosswind compensation differential torque ΔT_wind as joint decision variables for the same optimization problem. It solves the problem simultaneously under the same objective function and the unified constraints, and determines the final values ​​of T, ΔT_yaw, and ΔT_wind in one go. The vector unified execution module controls the drive system to output T and differential torque uniformly from the same power path; The real-time closed-loop correction module dynamically updates the solution input of the joint decision variables based on real-time feedback; The brake assist determination module determines whether the output capability of the drive system is sufficient to achieve the control target. If it is insufficient, it intervenes in the hydraulic braking system as an auxiliary means. All the modules mentioned above together constitute a vector unified control system, which uses the driving system as a unified vector execution entity and solves synchronously under unified constraints using a joint decision variable framework.

13. A unified vehicle dynamics vector control system according to claim 12, characterized in that, The drive system includes multiple independent drive motors. The output torque of each motor is uniformly incorporated into the joint decision variable solution module. Under the same unified constraint condition, the torque of each wheel or each axle is used as the joint decision variable for collaborative solution. The unified constraint condition is jointly formed by the adhesion boundary constraints of all drive wheels. The adhesion boundary of each wheel is established through the friction circle model, the tire force ellipse model or their equivalent approximate model. The multi-electric mechanism configuration includes, but is not limited to, a dual-motor four-wheel drive configuration with one drive motor on each of the front and rear axles and a configuration with an independent drive motor on each of the four wheels.

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