Complete vehicle comfort control method under impact degree ideal ellipse and acceleration test working condition

Abstract

The invention relates to a whole vehicle comfort level control method based on an impact degree ideal ellipse and an acceleration test condition. The method comprises the impact degree ideal ellipse (1), the acceleration-based test condition (2), a whole vehicle comfort level model (3), a whole vehicle comfort level control algorithm (4), a motor controller (5), a whole vehicle system (6) and the like. According to the whole vehicle comfort level control method, on the basis of a test working condition (2) based on acceleration, a working condition acceleration ae (203) curve serves as a control target of a vehicle comfort level test working condition; an ideal impact degree ellipse (1) is constructed, the acceleration and the impact degree serve as measurement standards of the comfort degree, and the comfort degree of the human body is improved from different dimensions; and (3) establishing a whole vehicle comfort level model, designing a whole vehicle comfort level control algorithm on this basis, and calculating the optimal output torque Tm (301) based on the impact degree ideal ellipse (1), thereby improving the comfort level in the whole driving process on the basis of satisfying the dynamic performance.

Description

Technical Field

[0001] The present invention relates to a control method for improving the comfort of a whole vehicle, and in particular to a whole vehicle comfort control method under an ideal ellipse impact and acceleration test condition. Background Art

[0002] With the rapid development of new energy technologies, pure electric vehicles are gaining a growing market share. Powered by electric motors, pure electric vehicles offer greater torque and a faster response than traditional fuel-powered vehicles, resulting in superior dynamic performance. However, these high torque and rapid response can lead to greater acceleration and impact.

[0003] The vestibular organs in the human ear sense the acceleration of the body's motion and head movement, adjusting relevant bodily functions to maintain balance. When a car is in high-speed motion and undergoes sudden acceleration, braking, or sharp turns, its acceleration can exceed the body's physiological threshold. However, the human body has a certain limit to the acceleration it can withstand. Beyond this threshold, discomfort begins to form, and this discomfort accumulates over time, potentially causing motion sickness symptoms such as dizziness and vomiting, which in turn reduces passenger comfort. Therefore, controlling acceleration plays a crucial role in overall driving comfort.

[0004] According to Newton's equation F = ma, when an object is subjected to a steady force, it will experience a constant acceleration. However, if this force suddenly changes, people will experience discomfort or even pain. This sudden change in force is called shock, which represents the rate of change of acceleration and reflects the trend of force changes. Shock is also an indicator of driving comfort.

[0005] Prior art 1, application number 202311083740.1, titled "Anti-motion sickness control method and system," obtains motion information including acceleration and angular velocity by acquiring initial and real-time imu numerical parameters to determine whether to activate the anti-motion sickness function. This invention only activates the anti-motion sickness function after the acquired imu numerical parameters reach a certain threshold, which cannot guarantee the comfort of the entire vehicle during the entire driving process and achieve the purpose of preventing motion sickness.

[0006] Prior art 2, application number 202310205402.4, entitled "A Method for Longitudinal and Lateral Control of an Anti-Motion Sickness Autonomous Vehicle," utilizes a nonlinear model predictive control algorithm to establish a driver model that integrates longitudinal and lateral control. After acquiring vehicle driving status and road surface information, the driver model outputs the desired speed, acceleration, and wheel angle to control the vehicle longitudinally and laterally, while ensuring safety and efficiency while minimizing motion sickness for passengers. This invention improves vehicle comfort throughout the driving process but fails to consider the impact of impact on vehicle comfort. Summary of the Invention

[0007] In order to address the shortcomings of the above-mentioned prior art, a vehicle comfort control method based on the ideal impact ellipse and acceleration test conditions is proposed. By combining the two important factors of acceleration and impact, the vehicle comfort during the entire driving process is improved while meeting the dynamic performance. The present invention includes the following steps:

[0008] Step 1: Construct the ideal impact ellipse (1)

[0009] A coordinate system is constructed with acceleration as the horizontal coordinate and impact degree as the vertical coordinate. An ideal impact degree ellipse (1) is constructed in the coordinate plane. The interior of the ideal impact degree ellipse (1) is defined as the comfort zone, and the exterior of the ideal impact degree ellipse (1) is defined as the non-comfort zone. Acceleration and impact degree are confined within the ideal impact degree ellipse (1).

[0010] Step 1.1: Digitalization of working condition standards

[0011] The working speed v e (202) and the data of the time t(201) coordinate axis are tabulated, and the working speed v is calculated with a step size of 1s. e (202) to arrange;

[0012] Step 1.2, draw a e -t coordinate map (205)

[0013] Process the tabulated data and calculate the working speed v e (202) is derived to obtain the working acceleration a e (203) and time t(201), plotted with the working acceleration a e (203) is the vertical axis, and time t(201) is the horizontal axis. e -t coordinate map (205);

[0014] Step 1.3, draw J e -t coordinate graph (206)

[0015] will a e-t coordinate diagram (205) data processing, the working condition acceleration a e (203) is derived to obtain the working condition impact degree J e (204) and time t(201), and the impact degree J of the working condition is plotted. e (204) is the vertical axis, and time t (201) is the horizontal axis. e -t coordinate map (206);

[0016] Step 1.4, draw J e -a e Coordinate chart (207)

[0017] will a e -t coordinate diagram (205) and J e -t coordinate diagram (206) is combined to obtain the working condition impact degree J e (204) and the working acceleration a e (203), and the impact degree J of the working condition is plotted. e (204) is the vertical coordinate, the working acceleration a e (203) is the J of the horizontal axis e -a e coordinate graph (207);

[0018] Step 1.5: Fitting the ideal impact ellipse (1)

[0019] J e -a e The points in the coordinate diagram (207) that are far from the center of the circle and have a low frequency of occurrence are removed, and an ellipse is fitted along the peripheral points to obtain the ideal ellipse (1) of the ideal impact degree;

[0020] The standardized equation of the ellipse is as shown in formula (3);

[0021]

[0022] In formula (3), x p Represents the translation distance of the standard ellipse along the x-axis (101), y p represents the translation distance of the standard ellipse along the y-axis (102), a represents the length of the major axis of the ellipse (103), b represents the length of the minor axis of the ellipse (104), θ r represents the angle (105) of the standard ellipse inversely rotated along the center point. Each parameter is related to the maximum acceleration and impact degree under the rule of the ideal ellipse (1) of the impact degree;

[0023] Step 1.6: Determine the working condition acceleration a e (203) and working condition impact strength J e Positional relationship between (204) and the ideal impact ellipse (1)

[0024] J e 、a e The numerical values ​​correspond to x and y, and are substituted into formula (5):

[0025]

[0026] If S>1, the working acceleration a e (203) and working condition impact strength J e (204) outside the ellipse;

[0027] When S≤1, the working acceleration a e (203) and working condition impact strength J e (204) On or inside the ellipse;

[0028] Step 1.7. Calculate the reference acceleration a r (402) and reference impact strength J r (403)

[0029] The ideal ellipse (1) of the impact degree is the working acceleration a e (203) and working condition impact degree J e (204) is limited to an elliptical range after translation and rotation, and the limited value is the reference acceleration a r (402) and reference impact strength J r (403).

[0030] Step 2: Establish acceleration-based test conditions (2)

[0031] The acceleration is used as the vertical coordinate and the time is used as the horizontal coordinate to form a coordinate system, and the acceleration-based test condition (2) is established. The acceleration a in the acceleration-based test condition (2) is converted to e (203) curve is used as the control target of the vehicle comfort test condition.

[0032] Step 3: Establish vehicle comfort model (3)

[0033] According to the longitudinal driving dynamics equation of the vehicle, the relationship equations between acceleration and impact degree and the parameters of the vehicle system (6) are solved respectively;

[0034] Step 3.1: Establish the vehicle motion equation

[0035]

[0036] In formula (6), T m The required vehicle power system torque T m (301), i0 is the transmission ratio (302), η Tis the transmission efficiency (303), r is the wheel radius (304), m is the vehicle mass (305), g is the acceleration due to gravity (306), f is the rolling resistance coefficient (307), C D is the air resistance coefficient (308), A is the frontal area (309), ρ is the air density (310), v is the vehicle speed (311), and δ is the vehicle rotation mass conversion factor (312);

[0037] Step 3.2: Establish vehicle speed dynamics model (315)

[0038] From formula (6), we can get:

[0039]

[0040] In formula (7), the speed at the current moment can be approximated by the speed v0 (401) at the previous moment;

[0041]

[0042] Step 3.3: Establish the vehicle acceleration dynamics model (316)

[0043]

[0044] In formula (9), T a (314) is the torque T m the first derivative of (301);

[0045]

[0046] Step 3.4: Establish the vehicle impact dynamics model (317)

[0047]

[0048] In formula (11), T J (315) is the torque T m The second derivative of (301);

[0049] Step 3.5: Obtain the vehicle comfort model (3)

[0050] The vehicle comfort model of the present invention is as follows:

[0051]

[0052] In formula (12), the state variables are x1=v, x2=a, x3=J, and the control input variable of the system is u=T m , the state space equation of the vehicle comfort control system is,

[0053]

[0054] In formula (13),

[0055]

[0056] Step 4: Design vehicle comfort control algorithm (4)

[0057] According to the vehicle comfort model (3), the state variables are x1 = v, x2 = a, x3 = J, and the control input variable of the system is u = T m The state space equation is used to establish a model prediction controller (408). According to the model prediction controller (408), the optimal motor drive torque T at the current moment is directly calculated. m (301);

[0058] Step 4.1: Establishing the Model Predictive Controller (408) Cost Function (404)

[0059]

[0060] In formula (14), e2 is the error of acceleration (405), e3 is the error of impact degree (406), where e2 = aa r 、e3=JJ r , Tr is the prediction cycle time (407), τ is the introduced time variable;

[0061] Taylor expansion of e2(t+τ) and e3(t+τ) to the first-order term yields equation (15):

[0062]

[0063] By combining equation (14), we can obtain:

[0064]

[0065] Step 4.2: Calculate the partial derivative of the cost function (404)

[0066]

[0067] Step 4.3: Set the partial derivative of the cost function (404) to zero

[0068]

[0069] From e2=aa r 、e3=JJ r We can get:

[0070]

[0071] Can be obtained:

[0072]

[0073] Substituting equations (19) and (20) into equation (18), we can obtain:

[0074]

[0075] Step 4.4, solve T m

[0076]

[0077] Furthermore, through the above steps, the model predictive controller (408) calculates the ideal torque T m (301), the motor controller (5) is based on the torque T m The (301) signal chops the three-phase full-bridge circuit and outputs the corresponding three-phase currents U, V, and W (501) to drive the entire vehicle system (6) in the longitudinal direction.

[0078] In summary, the present invention has the following advantages:

[0079] 1. Based on the acceleration-based test condition (2), the acceleration of the condition a e The (203) curve is used as the control target of the vehicle comfort test condition, which speeds up the response speed.

[0080] 2. Construct an ideal impact ellipse (1), using both acceleration and impact as comfort measurement standards to improve human comfort from different dimensions.

[0081] 3. Establish a vehicle comfort model (3), design a vehicle comfort control algorithm (4) based on this, and calculate the optimal output torque T based on the ideal impact ellipse (1) m (301), on the basis of satisfying the dynamic performance, improve the comfort level during the entire driving process. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] Figure 1 It is the construction of the ideal ellipse of the impact degree of the present invention;

[0083] Figure 2 The test conditions of CLTC-P, NEDC, UDDS and Japanese10-15 of the present invention are based on acceleration;

[0084] Figure 3 is the impact strength J of the working condition of the present invention eand working acceleration a e Process for determining the positional relationship with the ideal impact ellipse;

[0085] Figure 4 It is the vehicle comfort model of the present invention;

[0086] Figure 5 This is a block diagram of the vehicle comfort control algorithm of the present invention;

[0087] Table 1 Comparison table of serial number meanings.

[0088]

[0089] DETAILED DESCRIPTION

[0090] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the following further describes the vehicle comfort control method for the impact ideal ellipse and acceleration test conditions of the present invention in conjunction with the accompanying drawings and specific embodiments. The method comprises the following steps:

[0091] Step 1: Construct the ideal impact ellipse (1)

[0092] According to different working condition test standards such as China CLTC-P working condition test, Europe NEDC working condition test, United States UDDS working condition test, Japan Japanese10-15 working condition test, etc., a coordinate diagram with impact degree as the vertical coordinate and acceleration as the horizontal coordinate is obtained, which is fitted into an ellipse and the curve with the best comfort is selected as the ideal impact degree ellipse (1);

[0093] Furthermore, the construction of the ideal impact ellipse (1) described in step 1 includes the following steps:

[0094] Step 1.1: Digitalization of working condition standards

[0095] The working speed v e (202) and the data of the time t(201) coordinate axis are tabulated, and the working speed v is calculated with a step size of 1s. e (202) to arrange;

[0096] Step 1.2, draw a e -t coordinate map (205)

[0097] Process the tabulated data and calculate the working speed v e (202) is derived to obtain the working acceleration a e (203) and time t(201), plotted with the working acceleration a e (203) is the vertical axis, and time t(201) is the horizontal axis.e -t coordinate map (205);

[0098] Step 1.3, draw J e -t coordinate graph (206)

[0099] will a e -t coordinate diagram (205) data processing, the working condition acceleration a e (203) is derived to obtain the working condition impact degree J e (204) and time t(201), and the impact degree J of the working condition is plotted. e (204) is the vertical axis, and time t (201) is the horizontal axis. e -t coordinate map (206);

[0100] Step 1.4, draw J e -a e Coordinate chart (207)

[0101] will a e -t coordinate diagram (205) and J e -t coordinate diagram (206) is combined to obtain the working condition impact degree J e (204) and the working acceleration a e (203), and the impact degree J of the working condition is plotted. e (204) is the vertical coordinate, the working acceleration a e (203) is the J of the horizontal axis e -a e coordinate graph (207);

[0102] Step 1.5: Fitting the ideal impact ellipse (1)

[0103] J e -a e The points in the coordinate diagram (207) that are far from the center of the circle and have a low frequency of occurrence are removed, and an ellipse is fitted along the peripheral points to obtain the ideal ellipse (1) of the impact degree;

[0104] Furthermore, the fitting of the ideal shock ellipse (1) described in step 1.5 includes the following steps:

[0105] Step 1.5.1: Establish the general equation of the ellipse

[0106] x 2 +Axy+By 2 +Cx+Dy+E=0 (1)

[0107] In formula (1): A, B, C, D, E are coefficient terms;

[0108] Step 1.5.2: Fitting the ellipse equation using Matlab

[0109] The ideal ellipse of shock degree (1) was fitted by the least square method, and J e -a e Substitute the points outside the coordinate graph (207) into formula (2) and use matlab to perform fitting;

[0110]

[0111] Minimize the result of formula (2) and solve A, B, C, D, and E;

[0112] Among them Figure 1 As shown, it is the construction of the ideal impact ellipse (1) of the present invention, wherein the fitting ellipses under CLTC-P, NEDC, UDDS, and Japanese10-15 working conditions are respectively,

[0113] x 2 -2.2284xy+2.9844y 2 +0.1712x-0.2481y-1.6624=0

[0114] x 2 -0.9599xy+2.4752y 2 +0.0354x-0.2220y-0.9703=0

[0115] x 2 -1.7683xy+3.2577y 2 +0.1241x-0.3424y-1.9932=0

[0116] x 2 -1.5493xy+2.4117y 2 +0.0199x+0.0013y-0.6060=0

[0117] The innermost fitted ellipse under the Japanese10-15 working condition is taken as the ideal comfort ellipse (1);

[0118] Step 1.5.3: Standardization of the general ellipse equation

[0119] The standardized equation of the ellipse is as shown in formula (3);

[0120]

[0121] In formula (3), x p Represents the translation distance of the standard ellipse along the x-axis (101), y prepresents the translation distance of the standard ellipse along the y-axis (102), a represents the length of the major axis of the ellipse (103), b represents the length of the minor axis of the ellipse (104), θ r Represents the angle of the standard ellipse rotated inversely along the center point (105). The relationship between the parameters of the normalized equation and the coefficients A, B, C, D, and E in the general equation is as shown in formula (4);

[0122]

[0123] Step 1.6: Determine the working condition acceleration a e (203) and working condition impact J e Positional relationship between (204) and the ideal impact ellipse (1)

[0124] Among them Figure 3 As shown, the impact strength J of the working condition of the present invention is e (204) and the working acceleration a e (203) Method for determining the positional relationship with the ideal shock ellipse (1);

[0125] J e 、a e The numerical values ​​correspond to x and y, and are substituted into formula (5):

[0126]

[0127] If S>1, the working acceleration a e (203) and working condition impact J e (204) outside the ellipse;

[0128] When S≤1, the working acceleration a e (203) and working condition impact J e (204) On or inside the ellipse;

[0129] Step 1.7, calculation period reference acceleration a r (402) and reference impact strength J r (403)

[0130] The ideal ellipse (1) of the impact degree is the working acceleration a e (203) and working condition impact degree J e (204) is limited to an elliptical range after translation and rotation, and the limited value is the reference acceleration a r (402) and reference impact strength J r (403);

[0131] The horizontal coordinate value x of the leftmost point can be calculated from the equation of the ellipse L (106) and the rightmost point's horizontal coordinate value x R(107);

[0132] Substitute the working acceleration a e (203) to the x-coordinate in equation (1), and solve for the corresponding y-coordinate, i.e., the horizontal coordinate is the working acceleration a e (203) The vertical coordinate value y of the top point corresponding to the value T (108) and the ordinate value y of the lowest point B (109);

[0133] When S≤1, the reference acceleration a r (402) and reference impact strength J r The value of (403) is (a r , J r );

[0134] When S>1, the reference acceleration a needs to be limited r (402) and reference impact strength J r The value of (403);

[0135] Among them, when x L ≤a r ≤x R , and J r >y T , then the reference acceleration a r (402) and reference impact strength J r The value of (403) is (a r ,y T ); when x L ≤a r ≤x R , and J r <y B , then the reference acceleration a r (402) and reference impact strength J r The value of (403) is (a r ,y B );

[0136] when a r <x L , and J r >y T When the reference acceleration a r (402) and reference impact strength J r The value of (403) is (x L ,y T ); when a r <x L , and J r <y B When the reference acceleration a r (402) and reference impact strength Jr The value of (403) is (x L ,y B );

[0137] When x R r , and J r >y T When the reference acceleration a r (402) and reference impact strength J r The value of (403) is (x R ,y T ); when a r <x L , and J r <y B When the reference acceleration a r (402) and reference impact strength J r The value of (403) is (x R ,y B ).

[0138] Step 2: Establish acceleration-based test conditions (2)

[0139] The working speed v in the working condition test e (202) and the relationship between time t(201), converted to the working acceleration a e (203) and time t(201), constituted by the working condition acceleration a e (203) is the vertical axis, and time t(201) is the horizontal axis. e -t coordinate diagram (205), the working condition acceleration a e (203) curve as the control target of the vehicle comfort test condition;

[0140] Among them Figure 2 As shown, the test conditions of CLTC-P, NEDC, UDDS, and Japanese10-15 based on acceleration are shown in the figure. e -t coordinate map (205).

[0141] Step 3: Establish vehicle comfort model (3)

[0142] According to the longitudinal driving dynamics equation of the vehicle, the relationship equations between acceleration, impact degree and various parameters of the vehicle system (6) are solved respectively;

[0143] Furthermore, the establishment of the vehicle comfort model (3) described in step 3 includes the following steps:

[0144] Step 3.1: Establish the vehicle motion equation

[0145] ​

[0146] In formula (6), T m The required vehicle power system torque T m (301), i0 is the transmission ratio (302), η T is the transmission efficiency (303), r is the wheel radius (304), m is the vehicle mass (305), g is the acceleration due to gravity (306), f is the rolling resistance coefficient (307), C D is the air resistance coefficient (308), A is the frontal area (309), ρ is the air density (310), v is the vehicle speed (311), and δ is the vehicle rotation mass conversion factor (312);

[0147] Step 3.2: Establish vehicle speed dynamics model (315)

[0148] From formula (6), we can get:

[0149]

[0150] In formula (7), the speed at the current moment can be approximated by the speed v0 (401) at the previous moment;

[0151]

[0152] Step 3.3: Establish the vehicle acceleration dynamics model (316)

[0153]

[0154] In formula (9), T a (313) is the torque T m the first derivative of (301);

[0155]

[0156] Step 3.4: Establish the vehicle impact dynamics model (317)

[0157]

[0158] In formula (11), T J (314) is the torque T m The second derivative of (301);

[0159] Step 3.5: Obtain the vehicle comfort model (3)

[0160] Among them Figure 4 As shown, the vehicle comfort model of the present invention is as follows:

[0161]

[0162] In formula (12), the state variables are x1=v, x2=a, x3=J, and the control input variable of the system is u=T m , the state space equation of the vehicle comfort control system is,

[0163]

[0164] In formula (13),

[0165] Step 4: Design vehicle comfort control algorithm (4)

[0166] According to the vehicle comfort model (3), the state variables are x1 = v, x2 = a, x3 = J, and the control input variable of the system is u = T m A state-space equation is used to establish a model predictive controller (408);

[0167] Among them Figure 5 As shown in the block diagram of the vehicle comfort control algorithm based on the model predictive controller (408) in the present invention, the ideal ellipse (1) of the impact degree converts the working condition acceleration a e (203) and working condition impact degree J e (204) is limited to an elliptical range after translation and rotation, and the limited value is the reference acceleration a r (402) and reference impact strength J r (403), through the model prediction controller (408), the optimal motor drive torque T at the current moment is directly calculated. m (301) and input into the motor controller (5). The differential link (601) is used to differentiate the vehicle acceleration a (602) to obtain the vehicle impact degree J (603);

[0168] Furthermore, the design of the vehicle comfort control algorithm (4) described in step 4 includes the following steps:

[0169] Step 4.1: Establishing the Model Predictive Controller (408) Cost Function (404)

[0170]

[0171] In formula (14), e2 is the error of acceleration (405), e3 is the error of impact degree (406), where e2 = aa r 、e3=JJ r , Tr is the prediction cycle time (407), τ is the introduced time variable;

[0172] Taylor expansion of e2(t+τ) and e3(t+τ) to the first-order term yields equation (15):

[0173]

[0174] By combining equation (14), we can obtain:

[0175]

[0176] Step 4.2: Calculate the partial derivative of the cost function (404)

[0177]

[0178] Step 4.3: Set the partial derivative of the cost function (404) to zero

[0179]

[0180] From e2=aa r 、e3=JJ r We can get:

[0181]

[0182] Can be obtained:

[0183]

[0184] Substituting equations (19) and (20) into equation (18), we can obtain:

[0185]

[0186] Step 4.4, solve T m

[0187]

[0188] Furthermore, through the above steps, the model predictive controller (408) calculates the ideal torque T m (301), the motor controller (5) is based on the torque T m The (301) signal chops the three-phase full-bridge circuit and outputs the corresponding three-phase currents U, V, and W (501) to drive the vehicle in the longitudinal direction.

[0189] In summary, the present invention has the following advantages:

[0190] 1. Based on the acceleration-based test condition (2), the acceleration of the condition a e The (203) curve is used as the control target of the vehicle comfort test condition, which speeds up the response speed.

[0191] 2. Construct an ideal impact ellipse (1), using both acceleration and impact as comfort measurement standards to improve human comfort from different dimensions.

[0192] 3. Establish a vehicle comfort model (3), design a vehicle comfort control algorithm (4) based on this, and calculate the optimal output torque T based on the ideal impact ellipse (1) m (301), on the basis of satisfying the dynamic performance, improve the comfort level during the entire driving process.

Claims

1. A vehicle comfort control method for an ideal impact ellipse and acceleration test condition, characterized by: The method includes an ideal impact ellipse (1), an acceleration-based test condition (2), a vehicle comfort model (3), a vehicle comfort control algorithm (4), a motor controller (5), and a vehicle system (6). The method includes the following four steps: Step 1: Construct an ideal ellipse of impact strength (1); Step 2: Establishing acceleration-based test conditions (2); Step 3: Establish the vehicle comfort model (3); Step 4: Design the vehicle comfort control algorithm (4); According to the above four steps, the target torque T can be obtained m (301), input to the motor controller (5) to drive the entire vehicle system (6).

2. The ideal impact ellipse (1) according to claim 1, characterized in that: The coordinate system is constructed with acceleration as the horizontal coordinate and impact degree as the vertical coordinate. The ideal impact degree ellipse (1) is constructed in the coordinate plane. The inside of the ideal impact degree ellipse (1) is defined as the comfort zone, and the outside of the ideal impact degree ellipse (1) is defined as the non-comfort zone. The acceleration and impact degree are confined within the ideal impact degree ellipse (1). The equation of the constructed ideal impact degree ellipse (1) is as follows: In formula (3), x p Represents the standard ellipse translation distance along the x-axis (101), y p represents the translation distance of the standard ellipse along the y-axis (102), a represents the length of the major axis of the ellipse (103), b represents the length of the minor axis of the ellipse (104), θ r Represents the reverse rotation angle (105) of the standard ellipse around the center point.

3. The acceleration-based test condition (2) according to claim 1, characterized in that: The acceleration is used as the vertical coordinate and the time is used as the horizontal coordinate to form a coordinate system, and the acceleration-based test condition (2) is established. The acceleration a in the acceleration-based test condition (2) is converted to e (203) curve is used as the control target of the vehicle comfort test condition.

4. The vehicle comfort model (3) according to claim 1, characterized in that: Establishing vehicle speed dynamics model (315), In formula (8), T m The required vehicle power system torque T m (301), i0 is the transmission ratio (302), η T is the transmission efficiency (303), r is the wheel radius (304), m is the vehicle mass (305), g is the acceleration due to gravity (306), f is the rolling resistance coefficient (307), C D is the air resistance coefficient (308), A is the frontal area (309), ρ is the air density (310), v is the vehicle speed (311), and δ is the vehicle rotation mass conversion factor (312); Establishing the vehicle acceleration dynamics model (316), In formula (10), T a (313) is the torque T m the first derivative of (301); Establishing the impact dynamics model of the whole vehicle (317), In formula (11), T J (314) is the torque T m The second derivative of (301).

5. The vehicle comfort control algorithm (4) according to claim 1, characterized in that: According to the vehicle comfort model (3), the state variables are established as follows: x1=v,x2=a,x3=J The control input variables of the system are, u=T m The state space equation of the vehicle comfort control system is: In formula (13), Establishing the cost function (404) in the model predictive controller (408), In formula (14), e2 is the error of acceleration (405), e3 is the error of shock degree (406), Tr is the prediction cycle time (407), and τ is the introduced time variable; Taking the partial derivative of the cost function (404), Let the partial derivative of the cost function (404) be equal to zero, Calculate the output torque T m (301) for,

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