A new energy vehicle steering stability control system and method of a battery integrated roof

Abstract

This invention discloses a control architecture, control flow, and method for determining control parameters for a vehicle handling stability control system based on active pre-control of the chassis. The cornering prediction, electric power steering, and body control modules are connected to the body CAN bus, while the controllers for the active stabilizer bar, active suspension, electronic stability program, and active rear-wheel steering are connected to the chassis CAN bus. The central control unit acts as a gateway for the two CAN buses. By analyzing the steering wheel angle and steering signal, and referring to the steering duration, the system determines that the vehicle is about to enter a curve. Based on the vehicle speed and turning radius, it determines that the vehicle is in a high-speed sharp curve state. Upon confirmation, the control system is enabled, locking the vehicle speed and average curve radius at that moment. Based on the vehicle speed vector, curve radius vector, and numerical command matrix, the values ​​of each output variable are interpolated and determined, and then transmitted to each controller. This invention utilizes the control of various active chassis components to achieve handling stability during high-speed sharp turns, and is easy to implement.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle technology, and in particular to a new energy vehicle handling stability control system and method integrating a battery with the roof. Background Technology

[0002] Compared to the battery-to-chassis (CTC) structure, the battery-to-roof (CTR) structure in new energy vehicles can prevent toxic gases and fires from seeping into the cabin and protect passenger safety in the event of thermal runaway. The CTR structure is also beneficial for fire emergency response and timely fire suppression. Structurally, the CTR structure can simplify the battery waterproofing and dustproofing process and reduce costs.

[0003] Despite the many advantages of the CTR, placing the battery on the roof raises the vehicle's center of gravity, reducing overall handling stability. This could potentially cause the vehicle to roll over, especially during high-speed sharp turns, posing a risk of overturning.

[0004] Adding a counterweight box to the chassis can lower the center of gravity and improve the vehicle's handling stability, but it will reduce the vehicle's overall power and fuel economy.

[0005] With the increasing maturity of active chassis control technology, active stabilizer bars, active suspension, and active rear-wheel steering have all been mass-produced and installed in vehicles. How to use active chassis control technology to pre-control the vehicle before it turns, especially at high speeds, and improve the vehicle's handling stability is a technical problem that urgently needs to be solved. Summary of the Invention

[0006] To improve the handling stability of CTR new energy vehicles, this invention proposes a control architecture, control process, and method for determining various control parameters of a vehicle handling stability control system based on active pre-control of the chassis. The control system includes a cornering prediction controller (CPC), an electric power steering controller (EPSC), a body control module (BCM), a central control unit (CCU), an active roll control controller (ARCC), an active suspension control controller (ASCC), an electronic stability program controller (ESPC), and an active rear steering controller (ARSC).

[0007] CPC, EPSC, and BCM are connected to the body CAN (Controller Area Network), while ARCC, ASCC, ESPC, and ARSC are connected to the chassis CAN. The CCU connects the body CAN and chassis CAN, acting as a gateway between the two CAN buses.

[0008] The curve radius prediction system employs a fusion scheme of cameras, LiDAR, high-precision maps, inertial measurement units, and global navigation satellite systems. It can directly obtain three-dimensional geometric information and output the curve radius directly. It is unaffected by lighting conditions and works both day and night. It does not rely on lane lines and can identify any form of road boundary. Before a vehicle is about to enter a curve, the prediction system can provide the maximum, minimum, and average radius of the curve.

[0009] CPC transmits the average radius of the upcoming curve to CCU, EPSC transmits the steering wheel angle to CCU, and BCM transmits the driver's turn signal to CCU. After real-time calculation, CCU transmits torque commands to ARCC, force and height commands to ASCC, pressure commands to ESPC, and angle commands to ARSC via chassis CAN.

[0010] To achieve precise control of CTR new energy vehicles during high-speed sharp turns, this invention provides a control process based on active pre-control of the chassis. By analyzing the steering wheel angle and steering signal, and referencing the steering duration, the system determines that the vehicle is about to enter a curve. Based on the vehicle speed and turning radius, it determines that the vehicle is in a high-speed sharp turn state. Upon confirmation, the control system is enabled, locking the vehicle speed and average curve radius at that moment. Based on the vehicle speed vector, curve radius vector, and numerical command matrix, the values ​​of each output variable are interpolated and transmitted to each controller until the vehicle exits the curve. During the turn, the vehicle speed and turning radius change frequently. If the input values ​​at each sampling moment are used, the output commands will change frequently as one command is completed and the next command is issued consecutively, affecting the system's stability. Using the vehicle speed and average curve radius at the start of the turn represents the basic state of the curve and avoids frequent changes in output commands. The control process provided by this invention is as follows:

[0011] 1) System startup, a = 0;

[0012] 2) Status parameter input, including vehicle speed, steering signal, cornering radius and steering wheel angle, updated every 10ms;

[0013] 3) If a turning signal appears, proceed to step 4); otherwise, proceed to step 5.

[0014] 4) Determine if Ang_sw > Ang_s. If yes, proceed to 6); otherwise, a = 0, return to 2). Ang_s represents the steering angle corresponding to the maximum free travel of the steering wheel. When the steering wheel is greater than this value, the wheels start to turn. Ang_sw represents the real-time steering angle value of the steering wheel. If the driver turns the steering wheel and the real-time steering angle is greater than the steering angle corresponding to the maximum travel, it indicates that the driver is about to enter a curve.

[0015] 5) Determine if Ang_sw > Ang_s and the duration is greater than t_s. If yes, proceed to 6); otherwise, a = 0, return to 2); t_s represents the critical value of time; if some drivers forget to use their turn signals, and the real-time turning angle during the duration is found to be greater than the turning angle corresponding to the maximum travel, it indicates that they are about to enter a curve.

[0016] 6) Determine if v > v_s and r_a ≤ r_s. If yes, proceed to 7); otherwise, a = 0 and return to 2). v_s represents the critical value of vehicle speed. If it is greater than this value, it indicates that the vehicle is in a high-speed turning state. r_a represents the average radius of the curve, and r_s represents the critical value of the turning radius. If it is less than this value, it indicates that the vehicle is in a sharp turning state.

[0017] 7) Check if a = 0. If yes, proceed to 8); otherwise, return to 2).

[0018] 8) a = 1, enable the stability control system, and collect v and r_a at this time; after the control system is enabled, the values ​​of v and r_a are latched and maintained until the system is enabled.

[0019] 9) Determine if it is a right turn. If yes, proceed to 10); otherwise, proceed to 14).

[0020] 10) T_fl = interp2(Ria, Veo, Tor_f, r_a, v); T_fr = -interp2(Ria, Veo, Tor_f, r_a, v); T_rl = interp2(Ria, Veo, Tor_r, r_a, v); T_rr = -interp2(Ria, Veo, Tor_r, r_a, v); T_fl, T_fr, T_rl, and T_rr represent the torque control commands for the left, right, left, and right sides of the front axle, respectively, in ARCC; Ria and Veo represent the cornering radius and speed vector, Tor_f and Tor_r represent the torque matrices of the front and rear axles, respectively. Inputting r_a and v, the corresponding torque commands can be interpolated using interp2; when turning right, the left and right sides of the front and rear axles are positive, and the right and right sides of the front and rear axles are negative;

[0021] 11) F_l = interp2(Ria, Veo, For_o, r_a, v); F_r = -interp2(Ria, Veo, For_i, r_a, v); H_l = interp2(Ria, Veo, Hei, r_a, v); H_r = -interp2(Ria, Veo, Hei, r_a, v); F_l represents the control command for the front and rear left wheels in ASCC, F_r represents the control command for the front and rear right wheels, For_i and For_o represent the numerical matrices of the inner and outer forces, H_l represents the control command for the height of the front and rear left wheels in ASCC, H_r represents the control command for the height of the front and rear right wheels, Hei represents the numerical matrix of the height, with force and height being positive upwards and negative downwards;

[0022] 12) P_rr = interp2(Ria, Veo, Pre, r_a, v), where P_rr represents the control command for the right rear wheel pressure in ESPC, and Pre represents the pressure value matrix;

[0023] 13) A_r = -interp2(Ria, Veo, Ang, r_a, v), where A_r represents the control command for the rear wheel angle in ARSC, negative for right turn and positive for left turn, and Ang represents the numerical matrix of the angle;

[0024] 14) T_fl = -interp2(Ria, Veo, Tor_f, r_a, v); T_fr = interp2(Ria, Veo, Tor_f, r_a, v); T_rl = -interp2(Ria, Veo, Tor_r, r_a, v); T_rr = interp2(Ria, Veo, Tor_r, r_a, v); When turning left, the left side of the front axle and the left side of the rear axle are negative, and the right side of the front axle and the right side of the rear axle are positive;

[0025] 15) F_l=-interp2(Ria, Veo, For_i, r_a, v); F_r=interp2 (Ria, Veo, For_o, r_a, v); H_l=-interp2 (Ria, Veo, Hei, r_a, v); H_r=interp2 (Ria, Veo, Hei, r_a, v);

[0026] 16) P_lr = interp2(Ria, Veo, Pre, r_a, v), where P_lr represents the control command for the left rear wheel pressure in ESPC;

[0027] 17)A_r=interp2(Ria, Veo, Ang, r_a, v);

[0028] 18) T_fl, T_fr, T_rl and T_rr are sent to ARCC, F_l, F_r, H_l and H_r are sent to ARCC, P_lr and P_rr are sent to ESPC, and A_r is sent to ARSC;

[0029] 19) Jump to 2).

[0030] In practical application testing, it is necessary to comprehensively evaluate the impact of each control command on the vehicle's handling and stability performance, ensure that the actions of each actuator are coordinated, and avoid conflicts.

[0031] To ensure the accuracy and ease of implementation of parameters in the control flow, this invention provides a method for determining Tor_f, Tor_r, For_i, For_o, Hei, and Ang in the control flow:

[0032] 1) Calculate the lateral acceleration

[0033] Ria represents the turning radius vector, which consists of m different r values; Veo represents the vehicle speed vector, which consists of n different v values; the data in Ria and Veo are combined pairwise to form an n×m combination of r and v values ​​in n rows and m columns.

[0034] For a specific r and v, the corresponding lateral acceleration Ay is calculated as shown in formula (1);

[0035] Ay = v 2 / r (1)

[0036] 2) Calculate the roll torque and total lateral force

[0037] For a specific r and v, the corresponding total lateral force Fy and roll torque Tr are calculated as shown in formulas (2) and (3), where Mc represents the vehicle curb weight and h is the center of gravity height;

[0038] Fy=Mc×Ay (2)

[0039] Tr=Mc×Ay×h (3)

[0040] 3) Determine Tor_f and Tor_v

[0041] The formula for calculating the torque Tr_r provided by the stabilizer bar system is shown in formula (4), where Rr represents the torque ratio coefficient provided by the stabilizer bar.

[0042] Tr_r=Rr×Tr (4)

[0043] The formula for calculating the torque Tr_rf provided by the front axle stabilizer bar system is shown in formula (5), where Rr_f represents the torque ratio coefficient provided by the front stabilizer bar.

[0044] Tr_rf=Rr_f×Rr×Tr (5)

[0045] The formula for calculating the torque Tr_rr provided by the rear axle stabilizer bar system is shown in formula (6), where Rr_r represents the torque ratio coefficient provided by the rear stabilizer bar.

[0046] Tr_rr=Rr_r×Rr×Tr (6)

[0047] Considering the lever ratio, the formula for calculating the torque on one side of the front axle is shown in formula (7), where L_a represents the effective lever arm length;

[0048] Tr_rf_o=Tr_rf×0.5×L_a (7)

[0049] The formula for calculating the torque on one side of the rear axle is shown in formula (8);

[0050] Tr_rr_o=Tr_rr×0.5×L_a (8)

[0051] Tr_rf_o and Tr_rr_o are the torque commands corresponding to the stabilizer bars on the front and rear axle sides when r and v are respectively.

[0052] Similarly, calculate the specific values ​​corresponding to different r and v; n×m r and v can be used to calculate n×m Tr_rf_o and Tr_rr_o, forming an n-row m-column matrix Tor_f and Tor_r. The values ​​in the table are theoretical calculation values. In actual applications, the values ​​can be used as a reference point and fluctuated up and down to examine the changes in vehicle performance. The optimal value can be determined through calibration.

[0053] 4) Determine For_o and For_i

[0054] The torque Tr_s provided by the active suspension is calculated as shown in formula (9), where Rs represents the torque ratio coefficient provided by the active suspension.

[0055] Tr_s=Rs×Tr (9)

[0056] The minimum value r_min in Ria and the maximum value v_max in Veo correspond to the maximum force For_o_max of the outer suspension and the maximum force For_i_max of the inner suspension. For_i_max is set to be half of For_o_max.

[0057] Based on the characteristics of the active suspension, the maximum force Foro_max on the outside is determined according to Tr_s: Foro_rv and Fori_rv corresponding to any combination of r and v are calculated according to formulas (10) and (11);

[0058] For_o_rv=(v / v_max) 2 ×(r_min / r)×For_o_max (10)

[0059] For_i_rv=(v / v_max) 2 ×(r_min / r)×For_i_max (11)

[0060] n×m r and v can be used to calculate n×m For_o_rv and For_i_rv, forming an n-row m-column matrix For_o and For_i. The values ​​in the table are theoretical calculation values. In actual applications, these values ​​can be used as a reference point and fluctuated up and down to examine changes in vehicle performance. The optimal value can be determined through calibration.

[0061] 5) Determine Hei

[0062] Adjusting the posture in advance reduces dynamic response delay. The outer wheels can be raised 10-30mm in advance to compensate for compression caused by roll; the inner wheels can be lowered 10-30mm in advance to compensate for stretch.

[0063] The minimum value r_min in Ria and the maximum value v_max in Veo correspond to the maximum adjustable height Hei_max;

[0064] Based on the characteristics of the active suspension, Hei_max is determined; Hei_rv corresponding to any combination of r and v is calculated according to formula (12);

[0065] Hei_rv=(v / v_max) 2 ×(r_min / r)×Hei_max (12)

[0066] With n×m r and v values, the corresponding Hei_rv can be calculated, forming an n-row m-column matrix Hei. The values ​​in the table are theoretical calculation values. In actual applications, these values ​​can be used as a reference point and fluctuated up and down to examine changes in vehicle performance. The optimal value can be determined through calibration.

[0067] 6) Determine Ang

[0068] For a specific r and v, the rear wheel steering angle δ_rv is calculated according to formula (13), where L_b represents the wheelbase, K is the understeer coefficient of the vehicle, and f represents the proportional coefficient of the rear wheel steering angle;

[0069] δ_rv=(L_b / r+K×ay)×f (13)

[0070] For a specific r and v, the corresponding rear wheel steering angle δ_rv is calculated; n×m r and v can be used to calculate n×m δ_rv, forming an n-row m-column matrix Ang; during actual debugging, the values ​​in the table are used as the reference point, and the values ​​are fluctuated up and down to observe the changes in vehicle performance, and the optimal value is determined through calibration.

[0071] 7) Determine Pre

[0072] High-speed sharp turns are prone to understeer. ESC usually applies the brakes to the inside rear wheel to generate a yaw moment that makes the front of the car more lateral to the corner in order to correct the possible understeer.

[0073] The minimum value r_min in Ria and the maximum value v_max in Veo correspond to the maximum pressure command Pre_max. The Pre_rv corresponding to other combinations of r and v is calculated according to formula (14).

[0074] Pre_rv = (v / v_max) 2 ×(r_min / r)×Pre_max (14)

[0075] n×m r and v values ​​can be used to calculate n×m Pre_rv values, forming an n-row m-column matrix Pre. Using the values ​​in the table as a reference point, the values ​​are adjusted up and down to examine the changes in vehicle performance, and the optimal value is determined through calibration.

[0076] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0077] This invention improves the handling and stability performance of CTR vehicles through active pre-control of the chassis system. Before the vehicle enters a curve, the average curve radius and vehicle speed provided by the curve prediction system are used to determine the values ​​of the active stabilizer bar, active suspension, active rear-wheel steering, and ESP control parameters in real time. Through real-time control of each active component, potential vehicle rollover is prevented, improving the vehicle's handling and stability performance and ensuring passenger safety and comfort. Compared with improving vehicle handling and stability performance by adding weight, this method does not increase the vehicle's weight or cost, and improves the vehicle's power and economy. Attached Figure Description

[0078] The advantages of the present invention described above will become apparent and readily understood in conjunction with the description of the embodiments in conjunction with the accompanying drawings, wherein:

[0079] Figure 1 A control architecture for proactive pre-control of the chassis;

[0080] Figure 2 The control flowchart for proactive pre-control of the chassis. Detailed Implementation

[0081] The technical solution of the present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

[0082] like Figure 1 As shown, CPC, EPSC, and BCM are connected to the body CAN bus, while ARCC, ASCC, ESPC, and ARSC are connected to the chassis CAN bus; CCU connects the body CAN bus and the chassis CAN bus, serving as a gateway for the two CAN buses.

[0083] CPC transmits the average radius of the upcoming curve to CCU, EPSC transmits the steering wheel angle to CCU, and BCM transmits the driver's turn signal to CCU. After real-time calculation, CCU transmits torque commands to ARCC, force and height commands to ASCC, pressure commands to ESPC, and angle commands to ARSC via chassis CAN.

[0084] Figure 2The control process is as follows:

[0085] 1) System startup, a = 0;

[0086] 2) Input status parameters, including vehicle speed, steering signal, cornering radius, and steering wheel angle, updated every 10ms;

[0087] 3) If a turning signal appears, proceed to step 4); otherwise, proceed to step 5.

[0088] 4) Determine if Ang_sw > Ang_s. If yes, proceed to 6); otherwise, set a = 0 and return to 2).

[0089] 5) Determine if Ang_sw > Ang_s and the duration is greater than t_s. If yes, proceed to 6); otherwise, set a = 0 and return to 2).

[0090] 6) Determine if v > v_s and r_a ≤ r_s. If yes, proceed to 7); otherwise, a = 0 and return to 2).

[0091] 7) Check if a = 0. If yes, proceed to 8); otherwise, return to 2).

[0092] 8) a = 1, enable the stability control system, and collect v and r_a at this time; after the control system is enabled, the values ​​of v and r_a are latched and maintained until the system is enabled.

[0093] 9) Determine if it is a right turn; if yes, proceed to 10); if no, proceed to 14).

[0094] 10) T_fl=interp2(Ria, Veo, Tor_f, r_a, V); T_fr=-interp2(Ria, Veo, Tor_f, r_a, v); T_rl=interp2(Ria, Veo, Tor_r, ra, v); T_rr=-interp2(Ria, Veo, Tor_r, r_a, v);

[0095] 11) F_l=interp2(Ria, Veo, For_o, r_a, v); F_r=-interp2 (Ria, Veo, For_i, r_a, v); H_l=interp2 (Ria, Veo, Hei, r_a, v); H_r=-interp2 (Ria, Veo, Hei, r_a, v);

[0096] 12)P_rr=interp2(Ria, Veo, Pre, r_a, v);

[0097] 13)A_r=-interp2(Ria, Veo, Ang, r_a, v):,

[0098] 14) T_fl=-interp2(Ria, Veo, Tor_f, r_a, V); T_fr=interp2(Ria, Veo, Tor_f, r_a, v); T_rl=-interp2(Ria, Veo, Tor_r, r_a, v); T_rr=interp2(Ria, Veo, Tor_r, r_a, v);

[0099] 15) F_l=-interp2(Ria, Veo, For_i, r_a, v); F_r=interp2 (Ria, Veo, For_o, r_a, v); H_l=-interp2 (Ria, Veo, Hei, r_a, v); H_r=interp2 (Ria, Veo, Hei, r_a, v);

[0100] 16)P_lr=interp2(Ria,Veo,Pre,r_a,v);

[0101] 17)A_r=interp2(Ria, Veo, Ang, r_a, v);

[0102] 18) T_fl, T_fr, T_rl and T_rr are sent to ARCC, F_l, F_r, H_l and H_r are sent to ARCC, P_lr and P_rr are sent to ESPC, and A_r is sent to ARSC;

[0103] 19) Jump to 2).

[0104] In practical application testing, it is necessary to comprehensively evaluate the impact of each control command on the vehicle's handling and stability performance, ensure that the actions of each actuator are coordinated, and avoid conflicts.

[0105] Based on the parameters of a specific vehicle model, this invention provides a method for determining Tor_f, Tor_r, For_i, For_o, Hei, and Ang in the control flow; Table 1 shows the parameters of an example vehicle model and a curve.

[0106] Table 1 Vehicle and Curve Parameters

[0107] Serial Number Parameter name Parameter value unit 1 Maximum speed when turning 80 km / h 2 Minimum turning radius 50 m 3 curb weight 2300 kg 4 Center of mass height 0.75 m 5 wheelbase 2.9 m

[0108] The calculation steps are as follows:

[0109] 1) Calculate the lateral acceleration

[0110] Ria = [50, 60, 70, 80, 90], m = 5; Veo = [50, 60, 70, 80], n = 4; Ria and Veo will combine into 20 combinations of r and v; for a specific r and v, the corresponding lateral acceleration Ay is calculated as shown in formula (1);

[0111] Ay = v 2 / r (1)

[0112] When v is 80 km / h (approximately 22.22 m / s) and r is 50 m, Ay≈1.01g, where g represents the acceleration due to gravity.

[0113] 2) Calculate the roll torque and total lateral force:

[0114] For a specific r and v, the corresponding total lateral force Fy and roll torque Tr are calculated as shown in formulas (2) and (3), where Mc represents the vehicle curb weight.

[0115] Fy=Mc×Ay (2)

[0116] Tr=Mc×Ay×h (3)

[0117] When v is 80 km / h and r is 50 m, Fy = 2300 × 9.88 ≈ 22720 N, Tr = 2300 × 9.88 × 0.75 ≈ 17040 Nm.

[0118] 3) Determine Tor_f and Tor_v

[0119] The formula for calculating the torque Tr_r provided by the stabilizer bar system is shown in formula (4). The front and rear stabilizer bars are distributed in a 60:40 ratio, and Rr is equal to 0.4.

[0120] Tr_r=Rr×Tr (4)

[0121] When v is 80km / h and r is 50m, Tr_r is approximately 6816Nm.

[0122] The formula for calculating the torque Tr_rf provided by the front axle stabilizer bar system is shown in formula (5), where Rr_f equals 0.6;

[0123] Tr_rf=Rr_f×Rr×Mr (5)

[0124] When v is 80km / h and r is 50m, rr_rf is approximately 4090Nm.

[0125] The formula for calculating the torque Tr_rr provided by the rear axle stabilizer bar system is shown in formula (6), where Rr_r equals 0.4;

[0126] Tr_rr=Rr_r×Rr×Tr (6)

[0127] When v is 80km / h and r is 50m, Tr_rr is approximately 2726Nm.

[0128] The formula for calculating the torque on the front axle side is shown in formula (7), where La equals 0.735m;

[0129] Tr_rf_o=Tr_rf×0.5×L_a (7)

[0130] When v is 80km / h and r is 50m, Tr_rf_o is approximately equal to 1500Nm;

[0131] The formula for calculating the torque on the rear axle side is shown in formula (8);

[0132] Tr_rr_o=Tr_rr×0.5×L_a (8)

[0133] When v is 80 km / h and r is 50 m, Tr_rr_o is approximately equal to 1000 Nm;

[0134] 1500Nm is the torque command corresponding to the front axle when v is 80km / h and r is 50m, and 1000Nm is the torque command corresponding to the rear axle.

[0135] Based on the calculation method when v is 80km / h and r is 50m, calculate the specific values ​​corresponding to different v and r.

[0136] 4×5 r and v can be used to calculate 4×5 Tr_rf_o and Tr_rr_o, forming a 4x5 matrix Tor_f and Tor_r, as shown in Tables 1 and 2. The units of the values ​​in the tables are Nm. The values ​​in the tables are theoretical calculation values. In actual applications, the values ​​can be used as a reference point and fluctuated up and down to examine the changes in vehicle performance. The optimal value can be determined through calibration.

[0137] Table 1 Matrix Tor_f

[0138]

[0139] Table 2 Matrix Tor_r

[0140]

[0141] 4) Determine For_o and For_i

[0142] The torque Tr_s provided by the active suspension is calculated as shown in formula (9), and Rs equals 0.6;

[0143] Tr_s=Rs×Tr (9)

[0144] When v is 80km / h and r is 50m, Tr_s is approximately 11200Nm.

[0145] Referring to the characteristics of the example vehicle's suspension, the maximum force For_o_max on the outer side is 6000N, and the maximum force For_i_max on the inner side is 3000N;

[0146] For_o_rv and For_i_rv corresponding to any combination of r and v are calculated according to formulas (10) and (11);

[0147] For_o_rv=(v / 80) 2 ×(50 / r)×For_o_max (10)

[0148] For_i_rv=(v / 80) 2 ×(50 / r)×For_i_max (11)

[0149] 4×5 r and v are used to calculate 4×5 For_o_rv and For_i_rv, forming 4x5 matrices Tor_f and Tor_r, as shown in Tables 3 and 4. The units of the values ​​in the tables are N. The values ​​in the tables are theoretical calculation values. In actual applications, the values ​​can be used as a reference point and fluctuated up and down to examine the changes in vehicle performance. The optimal value can be determined through calibration.

[0150] Table 3 Matrix For_o

[0151]

[0152] Table 4 Matrix For_i

[0153]

[0154] 5) Determine Hei

[0155] The minimum speed in Ria is 50m, and the maximum speed in Veo is 80km / h, corresponding to a maximum adjustment height of Hei_max of 30mm.

[0156] Hei_rv corresponding to any combination of r and v is calculated according to formula (12);

[0157] Hei_rv=(v / 80) 2 ×(50 / r)×Hei_max (12)

[0158] With 4×5 r and v values, the corresponding Hei_rv can be calculated, forming a 4x5 matrix Hei, as shown in Table 5. The values ​​in the table are in mm. The values ​​in the table are theoretical calculation values. In actual applications, the values ​​can be used as a reference point and fluctuated up and down to examine the changes in vehicle performance. The optimal value can be determined through calibration.

[0159] Table 5 Matrix Hei

[0160]

[0161] 6) Determine Ang

[0162] For a specific r and v, the corresponding rear wheel steering angle δ_rv is calculated according to formula (13), where L_b equals 2.9m, K equals 0.005, and f equals 0.165;

[0163] δ_rv=(L_b / r+K×ay)×f (13)

[0164] For v = 80km / h and r = 50m, the corresponding δ_rv = 0.6°. Calculate the corresponding δ_rv using 4×5 r and v, forming a 4x5 matrix Ang, as shown in Table 6. The values ​​in the table are in degrees. During actual debugging, use the values ​​in the table as the reference point, and adjust them up and down to observe the changes in vehicle performance. Determine the optimal value through calibration.

[0165] Table 6 Matrix Ang

[0166]

[0167] 7) Determine Pre

[0168] The minimum value of 50m in Ria and the maximum value of 80km / h in Veo correspond to the maximum pressure command Pre_max of 12Mp. The Pre_rv corresponding to other r and v combinations is calculated according to formula (14).

[0169] Pre_rv = (v / 80) 2 ×(50 / r)×Pre_max (14)

[0170] Calculate the corresponding Pre_rv using 4×5 r and v values, forming a 4x5 matrix Pre, as shown in Table 7. The values ​​in the table are in MPa. During actual debugging, use the values ​​in the table as the reference point and adjust them up and down to observe the changes in vehicle performance. Determine the optimal value through calibration.

[0171] Table 7 Matrix Pre

[0172]

Claims

1. A vehicle handling stability control system based on chassis active pre-control, characterized in that: The control system includes a Curve Predictive Controller (CPC), an Electric Power Steering Controller (EPSC), a Body Control Module (BCM), a Central Control Unit (CCU), an Active Anti-roll Bar Controller (ARCC), an Active Suspension Controller (ASCC), an Electronic Stability Program Controller (ESPC), and an Active Rear Steering Controller (ARSC). CPC, EPSC, and BCM are connected to the body CAN (Controller Area Network), while ARCC, ASCC, ESPC, and ARSC are connected to the chassis CAN. The CCU connects the body CAN and chassis CAN, acting as a gateway between the two CAN buses. CPC transmits the radius of the upcoming curve to the CCU, EPSC transmits the steering wheel angle to the CCU, and BCM transmits the driver's steering signal to the CCU. After real-time calculation, the CCU transmits torque commands to the ARCC, force and height commands to the ASCC, pressure commands to the ESPC, and angle commands to the ARSC via the chassis CAN.

2. The control system according to claim 1, wherein the controller executes the following process: 1) System startup, a = 0; 2) Status parameter input, including vehicle speed, steering signal, cornering radius and steering wheel angle, updated every 10ms; 3) If a turning signal appears, proceed to step 4); otherwise, proceed to step 5. 4) Determine if Ang_sw > Ang_s. If yes, proceed to 6); otherwise, a = 0, return to 2). Ang_s represents the steering angle corresponding to the maximum free travel of the steering wheel. When the steering wheel is greater than this value, the wheels start to turn. Ang_sw represents the real-time steering angle value of the steering wheel. If the driver turns the steering wheel and the real-time steering angle is greater than the steering angle corresponding to the maximum travel, it indicates that the driver is about to enter a curve. 5) Determine if Ang_sw > Ang_s and the duration is greater than t_s. If yes, proceed to 6); otherwise, a = 0 and return to 2); t_s represents the critical value of time; if some drivers forget to use the turn signal when turning, and if the real-time turning angle during the duration is found to be greater than the turning angle corresponding to the maximum travel, it indicates that they are about to enter a curve; 6) Determine if v > v_s and r_a ≤ r_s. If yes, proceed to 7); otherwise, a = 0 and return to 2). v_s represents the critical value of vehicle speed. If it is greater than this value, it indicates that the vehicle is in a high-speed turning state. r_a represents the average radius of the curve, and r_s represents the critical value of the turning radius. If it is less than this value, it indicates that the vehicle is in a sharp turning state. 7) Check if a = 0. If yes, proceed to 8); otherwise, return to 2). 8) a = 1, enable the stability control system, and collect v and r_a at this time; after the control system is enabled, the values ​​of v and r_a are latched and maintained until the system is enabled. 9) Determine if it is a right turn. If yes, proceed to 10); otherwise, proceed to 14). 10) T_fl = interp2(Ria, Veo, Tor_f, r_a, v); T_fr = -interp2(Ria, Veo, Tor_f, r_a, v); T_rl = interp2(Ria, Veo, Tor_r, r_a, v); T_rr = -interp2(Ria, Veo, Tor_r, r_a, v); T_fl, T_fr, T_rl, and T_rr represent the torque control commands for the left, right, left, and right sides of the front axle, respectively, in ARCC; Ria and Veo represent the cornering radius and vehicle speed vector, Tor_f and Tor_r represent the torque matrices of the front and rear axles, respectively. Inputting r_a and v, the corresponding torque commands can be interpolated using interp2; when turning right, the left and right sides of the front and rear axles are positive, and the right and right sides of the front and rear axles are negative; 11) F_l = interp2(Ria, Veo, For_o, r_a, v); F_r = -interp2(Ria, Veo, For_i, r_a, v); H_l = interp2(Ria, Veo, Hei, r_a, v); H_r = -interp2(Ria, Veo, Hei, r_a, v): F_l represents the control command for the front and rear left wheels in ASCC, F_r represents the control command for the front and rear right wheels, For_i and For_o represent the numerical matrices of the inner and outer forces, H_l represents the control command for the height of the front and rear left wheels in ASCC, H_r represents the control command for the height of the front and rear right wheels, Hei represents the numerical matrix of the height, with force and height being positive upwards and negative downwards; 12) P_rr = interp2(Ria, Veo.Pre, r_a, v), where P_rr represents the control command for the right rear wheel pressure in ESPC, and Pre represents the pressure value matrix; 13) A_r = -interp2(Ria, Veo, Ang, r_a, v), where A_r represents the control command for the rear wheel angle in ARSC, negative for right turn and positive for left turn, and Ang represents the numerical matrix of the angle; 14) T_fl = -interp2(Ria, Veo, Tor_f, r_a, v); T_fr = interp2(Ria, Veo, Tor_f, r_a, v); T_rl′ = -interp2(Ria, Veo, Tor_r, r_a, v); T_rr = interp2(Ria, Veo, Tor_r, r_a, v); When turning left, the left side of the front axle and the left side of the rear axle are negative, and the right side of the front axle and the right side of the rear axle are positive; 15) F_l=-interp2(Ria, Veo, For_i, r_a, v); F_r=interp2 (Ria, Veo, For_o, r_a, v); H_l=-interp2 (Ria, Veo, Hei, r_a, v); H_r=interp2 (Ria, Veo, Hei, r_a, v); 16) P_lr = interp2(Ria, Veo, Pre, r_a, v), where P_lr represents the control command for the left rear wheel pressure in ESPC; 17)A_r=interp2(Ria, Veo, Ang, r_a, v); 18) T_fl, T_fr, T_rl and T_rr are sent to ARCC, F_l, Fr, H_l and H_r are sent to ARCC, P_lr and P_rr are sent to ESPC, and A_r is sent to ARSC; 19) Jump to 2).

3. The control system according to claim 1, wherein the control parameters Tor_f, Tor_r, For_i, For_o, Hei, and Ang are determined as follows: 1) Calculate the lateral acceleration Ria represents the turning radius vector, which consists of m different r values; Veo represents the vehicle speed vector, which consists of n different v values; the data in Ria and Veo are combined pairwise to form an n×m combination of r and v values ​​in n rows and m columns. For a specific r and v, the corresponding lateral acceleration Ay is calculated as shown in formula (1); Is = v 2 / r (1) 2) Calculate the roll torque and total lateral force For a specific r and v, the corresponding total lateral force Fy and roll torque Tr are calculated as shown in formulas (2) and (3), where Mc represents the vehicle curb weight and h is the vehicle center of gravity height. Fy=Mc×Ay (2) Tr=Mc×Ay×h (3) 3) Determine Tor_f and Tor_v The formula for calculating the torque Tr_r provided by the stabilizer bar system is shown in formula (4), where Rr represents the torque ratio coefficient provided by the stabilizer bar. Tr_r=Rr×Tr (4) The formula for calculating the torque Tr_rf provided by the front axle stabilizer bar system is shown in formula (5), where Rr_f represents the torque ratio coefficient provided by the front stabilizer bar. Tr_rf=Rr_f×Rr×Tr (5) The formula for calculating the torque Tr_rr provided by the rear axle stabilizer bar system is shown in formula (6), where Rr_r represents the torque ratio coefficient provided by the rear stabilizer bar. Tr_rr=Rr_r×Rr×Tr (6) Considering the lever ratio, the formula for calculating the torque on one side of the front axle is shown in formula (7), where L_a represents the effective lever arm length; Tr_rf_o=Tr_rf×0.5×L_a (7) The formula for calculating the torque on one side of the rear axle is shown in formula (8); Tr_rr_o=Tr_rr×0.5×L_a (8) Tr_rf_o and Tr_rr_o are the torque commands for the stabilizer bars on the front and rear axle sides when r and v are respectively: Similarly, calculate the specific values ​​corresponding to different r and v; n×m r and v can be used to calculate n×m Tr_rf_o and Tr_rr_o, forming an n-row m-column matrix Tor_f and Tor_r. The values ​​in the table are theoretical calculation values. In actual applications, the values ​​can be used as a reference point and fluctuated up and down to examine the changes in vehicle performance. The optimal value can be determined through calibration. 4) Determine For_o and For_i The torque Tr_s provided by the active suspension is calculated as shown in formula (9), where Rs represents the torque ratio coefficient provided by the active suspension. Tr_s=Rs×Tr (9) The minimum value r_min in Ria and the maximum value v_max in Veo correspond to the maximum force For_o_max of the outer suspension and the maximum force For_i_max of the inner suspension. For_i_max is set to be half of For_o_max. Based on the characteristics of the active suspension, the maximum force For_o_max on the outer side is determined according to Tr_s; For_o_rv and For_i_rv corresponding to any combination of r and v are calculated according to formulas (10) and (11); For_o_rv=(v / v_max) 2 ×(r_min / r)×For_o_max (10) For_i_rv=(v / v_max) 2 ×(r_min / r)×For_i_max (11) n×m r and v can be used to calculate n×m For_o_rv and For_i_rv, forming an n-row m-column matrix For_o and For_i; the values ​​in the table are theoretical calculation values. In actual applications, the values ​​can be used as a reference point and fluctuated up and down to examine the changes in vehicle performance. The optimal value can be determined through calibration. 5) Determine Hei Adjusting the posture in advance reduces dynamic response delay. The outer wheels can be raised 10-30mm in advance to compensate for compression caused by roll; the inner wheels can be lowered 10-30mm in advance to compensate for stretch. The minimum value r_min in Ria and the maximum value v_max in Veo correspond to the maximum adjustable height Hei_max; Based on the characteristics of the active suspension, Hei_max is determined; Hei_rv corresponding to any combination of r and v is calculated according to formula (12); Hei_rv=(v / v_max) 2 ×(r_min / r)×Hei_max (12) n×m r and v can be used to calculate the corresponding Hei_rv, forming an n-row m-column matrix Hei; the values ​​in the table are theoretical calculation values. In actual applications, the values ​​can be used as a reference point and fluctuated up and down to examine the changes in vehicle performance. The optimal value can be determined through calibration. 6) Determine Ang For a specific r and v, the rear wheel steering angle δ_rv is calculated according to formula (13), where L_b represents the wheelbase, K is the understeer coefficient of the vehicle, and f represents the proportional coefficient of the rear wheel steering angle; δ_rv=(L_b / r+K×ay)×f (13) For a specific r and v, the corresponding rear wheel steering angle δ_rv is calculated; n×m r and v can be used to calculate n×m δ_rv, forming an n-row m-column matrix Ang; during actual debugging, the values ​​in the table are used as the reference point, and the values ​​are fluctuated up and down to observe the changes in vehicle performance, and the optimal value is determined through calibration. 7) Determine Pre High-speed sharp turns are prone to understeer. ESC usually applies braking to the inside rear wheel to generate a yaw moment that makes the front of the car more lateral to the corner in order to correct the possible understeer. The minimum value r_min in Ria and the maximum value v_max in Veo correspond to the maximum pressure command Pre_max. The Pre_rv corresponding to other combinations of r and v is calculated according to formula (14). Pre_rv=(v / v_max) 2 ×(r_min / r)×Pre_max (14) n×m r and v values ​​can be used to calculate n×m Pre_rv values, forming an n-row m-column matrix Pre. Using the values ​​in the table as a reference point, the values ​​are adjusted up and down to examine the changes in vehicle performance, and the optimal value is determined through calibration.

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