Cabin parameter optimization method and system for improving sitting posture comfort of driver

Abstract

The invention relates to a cabin parameter optimization method and system for improving the sitting posture comfort of a driver, and relates to the technical field of automobile cabin comfort optimization. The minimum sum of distances between all driving sitting posture joint angles in a selected current group of comfortable joint angles and corresponding comfortable interval boundary values is used as an objective function; a set cabin parameter range is used as a constraint condition, a cabin parameter optimization model is constructed and solved, a cabin parameter optimal value is obtained, whether the corresponding driving sitting posture joint angle meets the comfort expectation or not is verified by using the cabin parameter optimal value in turn, cabin parameter adjustment amount optimization is performed, and while the cabin parameter adjustment amount is ensured to be as small as possible, the driving sitting posture joint angle can be accurately adjusted. According to the scheme, the number of the sitting posture joint angles of the driver in the comfort interval is as large as possible, a brand-new guidance optimization mode is provided for improving the sitting posture comfort of the driver, and compared with the current research on the driving sitting posture comfort only stays at the sitting posture comfort evaluation stage, the scheme more flexibly meets the actual requirements of automobile cabin development engineering.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile cockpit comfort optimization, and more specifically, to a cockpit parameter optimization method and system for improving driver's sitting comfort. Background Art

[0002] At present, the popularity of cars is increasing. As the driving time increases, on the one hand, drivers are prone to fatigue, which reduces driving safety; on the other hand, drivers are prone to low back pain and other phenomena, which reduces the subjective feeling of comfort.

[0003] In the driving posture, the load of the human head and torso is transferred to the pelvis through the sacroiliac joint, and the seat cushion bears about 75% of the body's weight. Under the action of local loads, muscle soft tissues are deformed. If they are in this working condition for a long time, blood circulation will be obstructed, the blood oxygen saturation of tissues will be reduced, leading to local ischemia, pain or numbness in the human body, and even chronic diseases such as low back pain. Therefore, how to reduce the physiological fatigue caused by cockpit elements (seats, steering wheels, pedals, etc.) to the body of drivers and passengers during road driving through reasonable ergonomic design and improve the comfort of driving posture as much as possible has become a technical problem that needs to be solved urgently.

[0004] The essence of driving posture is the specific joint angle formed by the joints of human limbs under the clear cockpit environment constraints (pedal layout, steering wheel layout and seat layout). At present, in the research on improving the comfort of driver's sitting posture, the main methods used are subjective evaluation based on experimental data, objective evaluation, combination of subjective and objective evaluation, and numerical simulation of skeletal muscle modeling. Among them, subjective evaluation is the most direct evaluation method for evaluating driving posture comfort. The driver's evaluation of comfort is obtained by scoring. For example, a quantitative evaluation method for driver's riding comfort is proposed in the prior art. The angles of multiple joints of the driver in a fixed state are collected and input into the driver's riding comfort evaluation model, and the driver's riding comfort evaluation model outputs the comfort score. However, on the one hand, this subjective evaluation method of outputting the comfort score by the driver's riding comfort evaluation model lacks reliability. On the other hand, the comfort evaluation is only a superficial feeling of the driver when driving. How to combine the comfort evaluation to optimize the cockpit parameter layout in depth to better improve the driver's sitting posture comfort? This scheme fails to combine the comfort score to give guidance and suggestions for the optimization of the sitting posture in a specific cockpit. In the objective evaluation method, the objective data is true and reliable, but the comfort level cannot be quantitatively evaluated. In the numerical simulation method, real-life motion simulation can be performed based on the human body's joint model, but the simulation often only focuses on a specific aspect of the driver's sitting comfort, ignoring the synergistic effect of multiple factors such as cockpit parameters. The accuracy of sitting comfort assessment is low, and it cannot provide guidance for improving the driver's sitting comfort, nor can it further flexibly adapt to the actual needs of the automotive cockpit development project. Summary of the invention

[0005] One of the purposes of the present invention is to provide a cockpit parameter optimization method for improving the driver's sitting comfort, so as to solve the problem that the current research on the driver's sitting comfort only stays at the sitting comfort evaluation stage and lacks a guiding optimization method for improving the driver's sitting comfort. A cockpit parameter optimization system for improving the driver's sitting comfort is also proposed.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A cockpit parameter optimization method for improving driver's sitting comfort comprises the following steps:

[0008] S1. Constructing a comfortable joint angle combination library; the comfortable joint angle combination library is provided with several groups of comfortable joint angles, each group of comfortable joint angles includes several driving sitting posture joint angles, and each driving sitting posture joint angle has a corresponding comfort interval;

[0009] S2. Taking the minimum sum of distances between all driving posture joint angles in the current group of comfortable joint angles and their corresponding comfort interval boundary values ​​as the objective function, and taking the set cockpit parameter range as the constraint condition, a cockpit parameter optimization model is constructed and solved to obtain the optimal value of the cockpit parameters;

[0010] S3. Determine whether all the driving posture joint angles in the current group of comfortable joint angles under the optimal value of the cockpit parameters are in the comfortable range. If so, output the optimal value of the cockpit parameters and execute step S4; otherwise, select the next group of comfortable joint angles and return to step S2;

[0011] S4. Taking the minimum Euclidean distance between the optimal value of the cockpit parameters and the initial value of the cockpit parameters as the objective function, and taking the unchanged comfort joint angle of the current group under the optimal value of the cockpit parameters as the constraint condition, the cockpit parameter adjustment optimization model is constructed and solved to obtain the optimal value of the adjusted cockpit parameters.

[0012] According to the above technical means, the objective function is to minimize the sum of the distances between all the driving posture joint angles in the selected current group of comfort joint angles and their corresponding comfort zone boundary values, and the set cockpit parameter range is used as a constraint condition to construct and solve the cockpit parameter optimization model. After the first step of optimization, the optimal values ​​of the cockpit parameters are obtained, and the optimal values ​​of the cockpit parameters are used to verify whether the corresponding driving posture joint angles meet the comfort expectations. Then, based on the first step of optimization, the cockpit parameter adjustment amount is optimized to ensure that the cockpit parameter adjustment amount is as small as possible and the number of driver's sitting posture joint angles in the comfort zone is as large as possible. This provides a new guiding optimization method for improving driver's sitting posture comfort. Compared with the current research on driving posture comfort that only stays in the sitting comfort evaluation stage, this solution is more flexibly adapted to the actual needs of automobile cockpit development projects.

[0013] Furthermore, the plurality of driving sitting posture joint angles include: elbow angle, shoulder angle, neck angle, back angle, hip angle, thigh angle and calf angle.

[0014] Furthermore, the process of obtaining the comfort zone is as follows:

[0015] Select a number of test drivers and different car models for testing;

[0016] Based on the limb size of the test driver, the analytical calculation model of the sitting posture joint angle is used to obtain the value of the test driver's driving sitting posture joint angle, and the comfortable range and uncomfortable range corresponding to different driving sitting posture joint angles are screened out;

[0017] Based on the comfortable range and uncomfortable range corresponding to the driving sitting posture joint angle, several groups of driving sitting posture joint angle grading evaluation data made by the test drivers facing different car models are obtained;

[0018] The driving sitting posture joint angle grading evaluation data is processed to obtain the comfort ranges of various driving sitting posture joint angles of test drivers of different genders and heights under tests of different vehicle models.

[0019] Furthermore, the process of screening out the comfortable range and uncomfortable range corresponding to the driving sitting posture joint angle is as follows:

[0020] Ask test drivers of different genders and heights to rate the comfort of the sitting joint angle when facing different models. The interval of the joint angle where the comfort score exceeds the set comfort score threshold is determined as the comfortable interval corresponding to the driving sitting joint angle, and the interval of the joint angle where the comfort score is less than the set comfort score threshold is determined as the uncomfortable interval corresponding to the driving sitting joint angle.

[0021] According to the combinations of different genders, different heights and different car models, several groups of driving posture joint angle grading evaluation data are obtained.

[0022] According to the above-mentioned technical means, based on the driving sitting posture joint angle data of the test drivers and the subjective comfort perception evaluation of the test drivers, the comfort ranges of various driving sitting posture joint angles of the test drivers of different genders and heights under different vehicle model tests are obtained, which provides a guiding standard for the subsequent verification of whether the driving sitting posture joint angle under the optimized value of the cockpit parameters meets the comfort expectations.

[0023] Furthermore, when processing the driving sitting posture joint angle grading evaluation data, the data in the first 15% to 35% and the last 15% to 35% of the driving sitting posture joint angle grading evaluation data are eliminated; the value of each driving sitting posture joint angle corresponding to the optimal evaluation data in the first 15% to 35% interval is used as the lower boundary value of the comfort range corresponding to each driving sitting posture joint angle, and the value of each driving sitting posture joint angle corresponding to the optimal evaluation data in the last 15% to 35% interval is used as the upper boundary value of the comfort range corresponding to each driving sitting posture joint angle.

[0024] According to the above technical means, the upper and lower boundary values ​​of the comfort zone are obtained while reducing the interference of abnormal values.

[0025] The test drivers were asked to rate the importance of different driving posture joint angles based on their subjective feelings of comfort;

[0026] Based on the test drivers' scores on the importance of different driving sitting posture joint angles, the average importance of different driving sitting posture joint angles was calculated, and the average importance was used as the scale of the hierarchical analysis method. The weights of each driving sitting posture joint angle of the test drivers were obtained by using the hierarchical analysis method.

[0027] For any driving posture joint angle A i, i = 1, ..., n, n represents the total number of driving posture joint angles. If the driving posture joint angle A i If the value of is within the comfort range, the comfort score of the driving sitting joint angle is recorded as 1; otherwise, the comfort score of the driving sitting joint angle is recorded as 0; add up all the comfort scores, and finally get the independent comfort score x of each driving sitting joint angle i ;

[0028] According to the weight of each driving posture joint angle and the independent comfort score x of each driving posture joint angle i , calculate the overall comfort score C of the driving sitting joint angle, the expression is:

[0029]

[0030] Among them, w i Represents the weight of each driving sitting posture joint angle of the test driver;

[0031] The independent comfort scores of various driving sitting posture joint angles are arranged and combined to obtain the overall comfort score after different driving sitting posture joint angle combinations, and at the same time, several groups of comfortable joint angles are formed, and the several groups of comfortable joint angles together constitute the comfortable joint angle combination library Deg.

[0032] According to the above technical means, the qualitative scoring evaluation of different driving sitting posture joint angles was carried out in combination with the subjective feeling of comfort of the test drivers. The average importance value of different driving sitting posture joint angles was used as the scale of the hierarchical analysis method. The thinking process was mathematized by combining qualitative and quantitative methods, and the hierarchical analysis method was used to obtain the weights of each driving sitting posture joint angle of the test drivers.

[0033] Further, in step S2, the selection process of the current group of comfortable joint angles is:

[0034] Calculate the overall comfort score of each group of comfortable joint angles in the comfortable joint angle combination library Deg;

[0035] The overall comfort score of each group of comfortable joint angles is sorted from high to low, and a group of comfortable joint angles is selected from the comfortable joint angle combination library Deg in the sorted order. As the current group of comfortable joint angles, j represents the group number of the selected comfortable joint angles.

[0036] According to the above technical means, after the overall comfort scores of all groups of comfortable joint angles are sorted from high to low, the comfortable joint angles are selected in sequence from the comfortable joint angle combination library Deg according to the sorting order. Among the group of comfort joint angles with the highest overall comfort score, the number of driving posture joint angles in the comfort zone is large. When optimizing the cockpit parameters, the order of the overall comfort score is used to preliminarily ensure that the number of driver's sitting posture joint angles in the comfort zone is as large as possible.

[0037] Further, in step S2, the cockpit parameters include: the horizontal distance L1 from the heel point to the R point, the horizontal distance L2 from the steering wheel center point to the R point, the vertical height H1 from the vehicle body floor to the R point, the vertical height H2 from the vehicle body floor to the steering wheel center point, the back angle A40, the pedal inclination angle A47, the initial value of the cockpit parameter is recorded as params0, and the cockpit parameter optimization model is:

[0038] Objective function:

[0039]

[0040] Among them, A i represents the i-th driving posture joint angle of the test driver, angel_bound i represents the boundary value of the comfort interval corresponding to the i-th driving sitting posture joint angle of the test driver, and the boundary value of the comfort interval is the upper boundary value or the lower boundary value of the comfort interval;

[0041] The cockpit parameter ranges include:

[0042] The horizontal distance L1 from the heel point to the R point satisfies: L1min≤L1≤L1max, where L1max represents the maximum value of the horizontal distance L1 from the heel point to the R point, and L1min represents the minimum value of the horizontal distance L1 from the heel point to the R point;

[0043] The horizontal distance L2 from the center point of the steering wheel to the point R satisfies: L2min≤L2≤L2max, where L2max represents the maximum value of the horizontal distance L2 from the center point of the steering wheel to the point R, and L2min represents the minimum value of the horizontal distance L2 from the center point of the steering wheel to the point R;

[0044] The vertical height H1 from the vehicle body floor to the point R satisfies: H1min≤H1≤H1max, where H1max represents the maximum value of the vertical height H1 from the vehicle body floor to the point R, and H1min represents the minimum value of the vertical height H1 from the vehicle body floor to the point R;

[0045] The vertical height H2 from the vehicle body floor to the center point of the steering wheel satisfies: H2min≤H2≤H2max, where H2max represents the maximum value of the vertical height H2 from the vehicle body floor to the center point of the steering wheel, and H2min represents the minimum value of the vertical height H2 from the vehicle body floor to the center point of the steering wheel;

[0046] The back angle A40 satisfies: αmin≤A40≤αmax, where αmin represents the minimum value of the back angle A40 and αmax represents the maximum value of the back angle A40;

[0047] The pedal inclination angle A47 satisfies: βmin≤A47≤βmax, where βmin represents the minimum value of the pedal inclination angle A47, and βmax represents the maximum value of the pedal inclination angle A47;

[0048] Among them, the heel point refers to the heel point of the driver's right foot when the driver's right foot is placed on the floor and the accelerator pedal; the R point refers to the seat reference point; the back angle A40 refers to the angle between the back line and the vertical direction, and the pedal inclination angle A47 refers to the angle between the pedal plane and the horizontal direction;

[0049] Therefore, the constraints are:

[0050] L1min≤L1≤L1max;

[0051] L2min≤L2≤L2max;

[0052] H1min≤H1≤H1max;

[0053] H2min≤H2≤H2max;

[0054] αmin≤A40≤αmax;

[0055] βmin≤A47≤βmax.

[0056] According to the above technical means, the cockpit parameters including the horizontal distance L1 from the heel point to the R point, the horizontal distance L2 from the steering wheel center point to the R point, the vertical height H1 from the body floor to the R point, the vertical height H2 from the body floor to the steering wheel center point, the back angle A40, and the pedal inclination angle A47 are taken as optimization variables to construct a cockpit parameter optimization model to fit the absolute distance between the cockpit parameters and the boundary values ​​of the comfort interval. The objective function is to minimize the sum of the distances between all driving sitting posture joint angles in the selected current group of comfort joint angles and their corresponding comfort interval boundary values, so that each driving sitting posture joint angle under the current group of comfort joint angles is within the comfort interval.

[0057] Furthermore, the method for solving the cockpit parameter optimization model is the trust region algorithm to obtain the optimal value of the cockpit parameters. The optimal value of the cockpit parameters currently solved by optimization is recorded as params j , params j It means to find a set of comfortable joint angle combinations with the highest overall comfort score. The corresponding cockpit parameter optimization model is the cockpit parameter optimization model obtained, params j Including the solved: the horizontal distance L1 from the heel point to point Rj , horizontal distance from the center of the steering wheel to point R L2 j , the vertical height from the vehicle body floor to point R H1 j , the vertical height from the vehicle body floor to the center point of the steering wheel H2 j 、Back angle A40 j 、Pedal inclination A47 j .

[0058] Further, in step S3, the process of judging whether each driving posture joint angle in the current group of comfortable joint angles under the optimal value of the cockpit parameter is in the comfortable range is as follows:

[0059] S31. Determine the optimal value of the cockpit parameters params obtained by the current optimization j Corresponding set of comfortable joint angles Whether all the values ​​of the driving posture joint angles in are within the comfort range, if so, executing step S4; otherwise, executing step S32;

[0060] S32. From the comfortable joint angle combination library Deg, select the next group of comfortable joint angles according to the overall comfort scores of all groups of comfortable joint angles from high to low Return to step S2; the comfortable joint angle The overall comfort score is less than the comfort joint angle Overall comfort score,

[0061] S33. Repeat steps S31 to S32 until a set of comfortable joint angles corresponding to the optimal values ​​of the cockpit parameters are optimized and solved. If all the driving posture joint angles are within the comfortable range, step S4 is executed.

[0062] According to the above technical means, based on the global convergence of the trust region algorithm, an optimal value of the cockpit parameters params must be obtained during the solution process j , check the optimal value of cockpit parameters params j Are the corresponding driving posture joint angles all in the comfortable range? If all the driving posture joint angles in the cockpit cannot be within the comfort range, the next set of comfortable joint angles will be reselected for cockpit parameter optimization to ensure that as many driving posture joint angles as possible are within the comfort range under cockpit parameter optimization.

[0063] Furthermore, the cockpit parameter adjustment optimization model constructed in step S4 includes:

[0064] Objective function:

[0065] min(params j -params0) 2

[0066] Constraints: The optimal values ​​of the cabin parameters params obtained in step S3 j The corresponding current group of comfortable joint angles constant.

[0067] Furthermore, the solution method of the cockpit parameter adjustment optimization model is the simplex method.

[0068] According to the above technical means, the optimal value of cockpit parameters params j Minimize the Euclidean distance from the initial value of the cockpit parameters and take the optimal value of the cockpit parameters params j The corresponding comfortable joint angle of the current group The constancy is used as a constraint condition to ensure that after the cockpit parameters are adjusted, the number of driving posture joint angles in the comfortable range does not change, so that the number of driving posture joint angles in the comfortable range after the cockpit parameters are optimized is as large as possible while the cockpit parameter adjustment amount is minimal.

[0069] A cockpit parameter optimization system for improving the sitting comfort of a driver, the system is used to implement the cockpit parameter optimization method for improving the sitting comfort of a driver, the system comprising:

[0070] A comfortable joint angle combination library construction unit is used to construct a comfortable joint angle combination library; the comfortable joint angle combination library is provided with a plurality of groups of comfortable joint angles, each group of comfortable joint angles includes a plurality of driving sitting posture joint angles, and each driving sitting posture joint angle has a corresponding comfort interval;

[0071] The cockpit parameter optimization unit takes the minimum sum of distances between all driving posture joint angles in the current group of comfortable joint angles and their corresponding comfort interval boundary values ​​as the objective function, takes the set cockpit parameter range as the constraint condition, builds and solves the cockpit parameter optimization model, and obtains the optimal value of the cockpit parameters;

[0072] The comfort interval verification unit is used to determine whether each driving posture joint angle in the current group of comfortable joint angles under the optimal value of the cockpit parameters is in the comfort interval. If so, the optimal value of the cockpit parameters is output; otherwise, the next group of comfortable joint angles is selected and input into the cockpit parameter optimization unit for cockpit parameter optimization;

[0073] The cockpit parameter adjustment optimization unit takes the minimum Euclidean distance between the optimal value of the cockpit parameter and the initial value of the cockpit parameter as the objective function, and takes the unchanged comfort joint angle of the current group under the optimal value of the cockpit parameter as the constraint condition. The cockpit parameter adjustment optimization model is constructed and solved to obtain the optimal value of the adjusted cockpit parameters.

[0074] An electronic device comprises a memory, a processor and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the steps of the cockpit parameter optimization method for improving the sitting comfort of the driver are implemented.

[0075] A computer storage medium stores a computer program, which is executed by a processor to implement the steps of the cockpit parameter optimization method for improving the sitting comfort of the driver.

[0076] Beneficial effects of the present invention:

[0077] The present invention proposes a cockpit parameter optimization method and system for improving the driver's sitting comfort, taking into account the influence of cockpit parameters on the driver's sitting comfort during the driver's driving process, taking the minimum sum of distances between all driving sitting joint angles in the selected current group of comfort joint angle combinations and their corresponding comfort interval boundary values ​​as the objective function, taking the set cockpit parameter range as the constraint condition, constructing and solving the cockpit parameter optimization model, after the first step of optimization, obtaining the optimal values ​​of the cockpit parameters, using the optimal values ​​of the cockpit parameters to in turn verify whether the corresponding driving sitting joint angles meet the comfort expectations, and then based on the first step of optimization, optimizing the cockpit parameter adjustment amount, while ensuring that the cockpit parameter adjustment amount is as small as possible, the number of the driver's sitting joint angles in the comfort interval is as large as possible, providing a new guiding optimization method for improving the driver's sitting comfort, compared with the current research on driving sitting comfort that only stays in the sitting comfort evaluation stage, this scheme is more flexibly adapted to the actual needs of automobile cockpit development projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] Figure 1 A schematic diagram showing a flow chart of a cockpit parameter optimization method for improving the driver's sitting comfort proposed in an embodiment of the present invention;

[0079] Figure 2 An overall schematic diagram of a dummy sitting joint angle model proposed in an embodiment of the present invention is shown;

[0080] Figure 3 A schematic diagram of a sitting joint angle model of a dummy's lower body proposed in an embodiment of the present invention is shown;

[0081] Figure 4 A schematic diagram of a sitting joint angle model of a dummy upper body proposed in an embodiment of the present invention is shown;

[0082] Figure 5 A schematic diagram showing the classification and evaluation of the driving posture joint angles proposed in an embodiment of the present invention;

[0083] Figure 6A schematic diagram showing a flow chart of obtaining the weights of each driving sitting posture joint angle of the test driver by using the hierarchical analysis method proposed in an embodiment of the present invention;

[0084] Figure 7 A schematic diagram showing a process of optimizing cockpit parameters using a trust region algorithm proposed in an embodiment of the present invention;

[0085] Figure 8 A schematic diagram showing a flow chart of optimizing cockpit parameter adjustment amount by using simplex generation proposed in an embodiment of the present invention;

[0086] Fig. 9 A detailed flow chart of the cockpit parameter optimization method for improving the driver's sitting comfort proposed in an embodiment of the present invention;

[0087] Fig.10 A schematic diagram showing the structure of a cockpit parameter optimization system for improving the driver's sitting comfort proposed in an embodiment of the present invention;

[0088] Fig.11 A schematic diagram showing an electronic device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0089] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0090] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0091] First, the English words and terms mentioned in the embodiments of the present invention are explained.

[0092] The 5th, 50th and 95th percentiles of height size: Since people's height size varies greatly, it is not a definite value, but is distributed within a certain range. The test drivers are divided into 100 parts and arranged in order from smallest to largest according to some specified human body size items (such as height). The end point of each section is a percentile. The percentile indicates the percentage of people with a certain human body height size and less than this height size in the total number of test drivers. The 5th percentile means that 5% of the people are equal to or less than this size in height, the 50th percentile means that 50% of the people are equal to or less than this size in height, and the 95th percentile means that 95% of the people are equal to or less than this size in height.

[0093] SUV, Sport Utility Vehicle, sports utility vehicle.

[0094] MPV, Multi-Purpose Vehicles, multi-purpose vehicles.

[0095] SAE, Society of Automotive Engineers, American Society of Automotive Engineers.

[0096] Heel point, R point, A40 and A47 are all codes specified in "SAE J1100 Motor Vehicle Dimensions".

[0097] This embodiment proposes a cockpit parameter optimization method for improving the driver's sitting comfort. Figure 1 , specifically including the following steps:

[0098] S1. Constructing a comfortable joint angle combination library; the comfortable joint angle combination library is provided with several groups of comfortable joint angles, each group of comfortable joint angles includes several driving sitting posture joint angles, and each driving sitting posture joint angle has a corresponding comfort interval;

[0099] S2. Taking the minimum sum of distances between all driving posture joint angles in the current group of comfortable joint angles and their corresponding comfort interval boundary values ​​as the objective function, and taking the set cockpit parameter range as the constraint condition, a cockpit parameter optimization model is constructed and solved to obtain the optimal value of the cockpit parameters;

[0100] S3. Determine whether all the driving posture joint angles in the current group of comfortable joint angles under the optimal value of the cockpit parameters are in the comfortable range. If so, output the optimal value of the cockpit parameters and execute step S4; otherwise, select the next group of comfortable joint angles and return to step S2;

[0101] S4. Taking the minimum Euclidean distance between the optimal value of the cockpit parameters and the initial value of the cockpit parameters as the objective function, and taking the unchanged comfort joint angle of the current group under the optimal value of the cockpit parameters as the constraint condition, the cockpit parameter adjustment optimization model is constructed and solved to obtain the optimal value of the adjusted cockpit parameters.

[0102] In the specific process of building the comfortable joint angle combination library described in step S1, the comfortable range is first obtained, which specifically includes:

[0103] S11. Select a number of test drivers and different vehicle models for testing; in this embodiment, 90 test drivers are selected, and the test drivers include male and female, including 60 male drivers and 30 female drivers. The height size of the test drivers includes the 5th percentile, the 50th percentile and the 95th percentile. The different vehicle models used for testing include sedans, SUVs and MPVs.

[0104] S12. Based on the limb size of the test driver, the value of the test driver's driving sitting joint angle is obtained by using the sitting joint angle analytical calculation model, and the comfortable range and uncomfortable range corresponding to different driving sitting joint angles are screened out;

[0105] In this embodiment, see Figure 2 , the driving posture joint angles include: elbow angle, shoulder angle, neck angle, back angle, hip angle, thigh angle and calf angle. The corresponding codes in "SAE J1100 Motor Vehicle Dimensions" are elbow angle A1, shoulder angle A2, neck angle A3, trunk angle A4, hip angle A5, thigh angle A6, calf angle A7, corresponding to Figure 2 The angle markings shown in .

[0106] From the perspective of the sitting posture formation principle, when the limb dimensions of the test driver and the cockpit layout parameters are known, any joint angle of the human body can be solved by analytical calculation. The process of solving the sitting posture joint angle analytical calculation model in step S22 is:

[0107] First, the joint angle model of the dummy sitting posture is assumed, see Figure 2 , including three assumptions:

[0108] Assumption 1: The dummy's foot sole plane is completely parallel to the pedal plane, and the intersection of the pedal plane and the cockpit floor is the dummy's heel point;

[0109] Assumption 2: The dummy's back fits perfectly against the seat back, with the buttocks at the deepest part of the seat cushion;

[0110] Assumption 3: The dummy's shoulder joint is fixed, there is no forward or backward shoulder movement, and the upper arm only rotates relative to the shoulder joint (greater trochanter point of the upper arm).

[0111] The body dimensions of the dummy (see Figure 2 The distances BC from shoulder to elbow, CD from elbow to wrist, BH from shoulder to hip, HE from hip to knee, EF from knee to ankle, and FG from ankle to heel are all known. Related parameters include the horizontal distance L1 from heel to point R, the horizontal distance L2 from the center of the steering wheel to point R, the vertical height H1 from the vehicle body floor to point R, the vertical height H2 from the vehicle body floor to point A of the steering wheel, the trunk angle A4, and the pedal inclination A47. The analytical calculation model of the sitting posture joint angle is used to solve all unknown joint angles. The calculation of the driving sitting posture joint angle can be split into the solution of two major parts of the dummy body, namely the upper body and the lower body. First, the relevant joint angles of the dummy's lower body are solved, and then the calculation of the driving posture joint angle is combined with the calculation of the driving posture joint angle. Figure 3 Use the marked points and lines shown to make auxiliary lines. The relevant auxiliary line details are described as follows:

[0112] (1) Connect the IF and regard the test driver's foot as a ΔIGF;

[0113] (2) Draw FJ⊥IG through point F, with J as the perpendicular point;

[0114] (3) Extend EF to intersect IG at point K;

[0115] (4) Draw FM through point F ⊥ floor GM, with M as the vertical point;

[0116] (5) Draw a line FL parallel to the floor through point F;

[0117] Since the body size of the test driver is known, the lengths of FJ and FG are known. Since FJ⊥IG, the solution expression for ∠FGJ satisfies:

[0118]

[0119]

[0120] ∠KGN is the known setting angle (known), according to:

[0121] ∠KNG+∠FGJ+∠FGM=180° (3)

[0122] So: ∠FGM=180°-∠KGN-∠FGJ, ∠GFM=90°-∠FGM, according to:

[0123] GM=GF×cos∠FGM (4)

[0124] FM=GF×sin∠FGM (5)

[0125] Therefore, we can get FL = L1-GM, HL = H1-FM, according to:

[0126]

[0127]

[0128] That is, the length of FH is obtained. Since EF and EH are known, ∠A6 is obtained as:

[0129]

[0130] Similarly, ∠EFH and ∠EHF can be obtained according to the cosine formula;

[0131] Because: ∠EFH+∠HFL+∠GFM+∠KFG=90°, we can get: ∠KFG

[0132] And because: ∠JKF=∠KFG+∠FGJ, we can get: ∠A7=∠JKF

[0133] In ΔHFL, FL, HL and FH are all known, and FL⊥HL, ∠HFL is known, and ∠FHL=90°-∠HFL. Since ∠EHO=180°-∠EHF-∠FHL, ∠A5=∠EHO+∠A4 can be obtained.

[0134] At this point, the lower body angles ∠A7, ∠A6, and ∠A5 have all been calculated.

[0135] Solve the joint angle of the lower body driving posture, and draw auxiliary lines for the joint angle of the upper body driving posture as follows:

[0136] (1) See Figure 4 , taking point P as the corner point of the two reference lines;

[0137] (2) Draw a perpendicular line BQ through point B, perpendicular to the reference line at the center of the steering wheel, and intersect the perpendicular reference line at point Q;

[0138] Given the heights H2 and H1, and the lengths DC, BC, and BH, we can calculate HP and BP based on the law of cosines:

[0139] HP=BH×sin∠A4 (9)

[0140] BP=BH×cos∠A4 (10)

[0141] Since the height of point B HB=BP+H1, and QD+H2=HB, so: DQ=HB-H2;

[0142] Because: QB=L2+HP, according to the Pythagorean theorem, the length of QB is:

[0143]

[0144] Since the lengths of the three sides of ΔBCD are known, ∠A1 can be obtained according to the cosine theorem.

[0145]

[0146] Similarly, ∠DBC can be obtained;

[0147] In RtΔBDQ, according to the sine theorem, ∠QBD can be obtained

[0148]

[0149] Because ∠QBD+∠DBC+∠A2+∠A4=90°, we can get ∠A2=90°-∠A4-∠DBC-∠QBD;

[0150] At this point, all the relevant joint angles ∠A1 and ∠A2 of the upper body have been calculated. ∠A3 lacks constraints and is set as the default design value by the engineer.

[0151] After obtaining the value of the driving sitting joint angle of the test driver, based on the selected test drivers and different models used for testing (60 male drivers and 30 female drivers, the height size of the test drivers includes the 5th percentile, 50th percentile and 95th percentile, and the different models used for testing include sedans, SUVs and MPVs), the process of screening out the comfortable range and uncomfortable range corresponding to the driving sitting joint angle is as follows:

[0152] The test drivers of different genders and heights are asked to score the comfort of the sitting joint angle when facing different types of vehicles. The interval of the joint angle where the comfort score exceeds the set comfort score threshold is determined as the comfort interval corresponding to the driving sitting joint angle, and the interval of the joint angle where the comfort score is less than the set comfort score threshold is determined as the discomfort interval corresponding to the driving sitting joint angle.

[0153] In this embodiment, when facing different models, the test driver scores the comfort of the sitting joint angle in combination with the SAE ten-level comfort evaluation scale. The SAE ten-level comfort evaluation scale is divided into 1 to 10 levels. A driving sitting joint angle of each test driver corresponds to a comfort score. In summary, the driving sitting joint angle comfort scores of the test driver under different comfort evaluations can be obtained. The comfort score threshold is set to 6 points, and the angle value interval corresponding to the driving sitting joint angle with a score exceeding 6 points is determined as the comfort interval, and the angle value interval outside the comfort interval is the discomfort interval, and then step S13 is executed:

[0154] S13. Based on the comfortable range and uncomfortable range corresponding to the driving sitting posture joint angle, obtain several groups of driving sitting posture joint angle grading evaluation data made by the test drivers facing different vehicle models;

[0155] In this step, the differences in driving posture joint angles caused by different genders, different height sizes, and different models are further considered. According to the arrangement and combination of different genders, different height sizes, and different models, the driving posture joint angle classification evaluation diagram is shown in the figure below: Figure 5 As shown, there are 2*3*3=18 groups of joint angle classification evaluation data, among which there are two groups for gender, three groups for height size, namely the 5th percentile, 50th percentile and 95th percentile, and three groups for vehicle types, namely sedan, SUV and MPV. Figure 5 The comfort zone and discomfort zone screening for each specific group are briefly illustrated in Figure 5 In the lower part, for males and the 5th percentile, facing sedan models, the comfortable intervals and unacceptable intervals (uncomfortable intervals) corresponding to the elbow angle, shoulder angle, neck angle, back angle, hip angle, thigh angle and calf angle are obtained in turn. For females and the 95th percentile, facing MPV models, the comfortable intervals and unacceptable intervals (uncomfortable intervals) corresponding to the elbow angle, shoulder angle, neck angle, back angle, hip angle, thigh angle and calf angle are obtained in turn. To reduce the interference of abnormal values, step S14 is performed:

[0156] S14. Processing the driving posture joint angle grading evaluation data, to obtain the comfort ranges of various driving posture joint angles of test drivers of different genders and heights under tests of different vehicle models.

[0157] When processing the driving posture joint angle grading evaluation data, the data in the first 15% to 35% and the last 15% to 35% of the driving posture joint angle grading evaluation data are eliminated; the value of each driving posture joint angle corresponding to the optimal evaluation data in the first 15% to 35% interval is used as the lower boundary value of the comfort range corresponding to each driving posture joint angle, and the value of each driving posture joint angle corresponding to the optimal evaluation data in the last 15% to 35% interval is used as the upper boundary value of the comfort range corresponding to each driving posture joint angle. In this embodiment, the box plot-quartile division method is used to eliminate the data in the top 25% and bottom 25% of the driving posture joint angle grading evaluation data; the values ​​of each driving posture joint angle corresponding to the 25th percentile are used as the optimal evaluation data in the top 15% to 35% interval, and the corresponding values ​​of each driving posture joint angle are used as the lower boundary value of the comfort interval; the values ​​of each driving posture joint angle corresponding to the 75th percentile are used as the optimal evaluation data in the bottom 15% to 35% interval, and the corresponding values ​​of each driving posture joint angle are used as the upper boundary value of the comfort interval, so as to reduce the interference of abnormal values ​​while obtaining the upper and lower boundary values ​​of the comfort interval. This embodiment uses the 5th percentile, 50th percentile and 95th percentile shown in Table 1 to provide a statistical illustration of the driving posture joint angle comfort intervals.

[0158] Table 1

[0159]

[0160] The mean values ​​shown in Table 1 have certain statistical significance, but in this embodiment, the upper boundary value and the lower boundary value of the obtained comfort interval are used as the boundary values ​​of the obtained comfort interval, and the mean value is not used as a reference.

[0161] On the premise of obtaining the comfort interval, the process of constructing a comfortable joint angle combination library is as follows:

[0162] S101. Ask the test drivers to score the importance of different driving sitting posture joint angles according to their subjective feelings of comfort; in this embodiment, several test drivers are selected to rank and score the importance of each driving sitting posture joint angle. An example diagram of the test drivers scoring the importance of different driving sitting posture joint angles according to their subjective feelings of comfort is shown in Table 2. In Table 2, each test driver is numbered. Table 2 shows the numbers of 13 test drivers, and then each test driver scores the importance of different driving sitting posture joint angles based on his or her personal subjective feelings. The specific values ​​of the importance scores are shown in Table 2.

[0163] Table 2

[0164] Test No. Elbow Angle Shoulder angle Neck angle Back angle Hip angle Thigh angle Calf angle 1 4 6 7 3 5 2 1 2 3 7 6 5 4 2 1 3 2 1 7 3 4 6 5 4 1 5 6 2 3 7 4 5 6 1 2 3 4 7 5 6 1 2 4 3 7 6 5 7 2 6 1 7 5 4 3 8 2 1 5 3 4 7 6 9 7 2 5 6 4 1 1 10 5 2 6 7 4 3 1 11 2 3 7 5 6 4 1 12 1 7 2 3 5 6 4 13 5 4 6 3 7 2 1

[0165] S102. Based on the test driver's scores on the importance of different driving sitting posture joint angles, the importance averages of different driving sitting posture joint angles are calculated, the importance averages are used as the scale of the hierarchical analysis method, and the weights of each driving sitting posture joint angle of the test driver are obtained by using the hierarchical analysis method;

[0166] In this embodiment, the importance average is calculated by taking the sum of the scores of all the test drivers on a certain driving joint angle, and then taking the average value, and the importance average of the joint angles of different driving sitting postures is obtained as follows:

[0167] Shoulder angle: 3.833; Neck angle: 4.344; Back angle: 4.622; Hip angle: 4.622; Thigh angle: 3.711; Calf angle: 3.000; Elbow angle: 3.867.

[0168] However, simple importance average calculation is not enough to clearly express the weights of different driving posture joint angles. Therefore, the importance average is used as the scale of the hierarchical analysis method, and the hierarchical analysis method is used to obtain the weights of each driving posture joint angle of the test driver. The hierarchical analysis method organizes and hierarchizes the problem by analyzing the factors and correlations contained in the complex system, compares the elements of each level two by two, and obtains the relative importance comparison scale and establishes a judgment matrix according to a certain scaling theory. In this embodiment, when there are multiple subjects, the calculated importance average is used as the comparison scale of the hierarchical analysis method, and the judgment matrix is ​​obtained by dividing the average value. The larger the average value means the higher the importance, and the higher the weight obtained in the subsequent analysis. The process of obtaining the weights of each driving posture joint angle of the test driver using the hierarchical analysis method can be found in Figure 6 , specifically:

[0169] (1) Using the calculated importance average as the comparison scale, a pairwise comparison judgment matrix X is constructed. In this embodiment, the constructed comparison judgment matrix X is shown in Table 3.

[0170] Table 3

[0171] Matrix element term Shoulder angle Neck angle Back angle Hip angle Thigh angle Calf angle Elbow Angle Shoulder angle 1 0.882 0.829 0.829 1.033 1.278 0.991 Neck angle 1.133 1 0.940 0.940 1.171 1.448 1.124 Back angle 1.206 1.064 1 1 1.246 1.541 1.195 Hip angle 1.206 1.064 1 1 1.246 1.541 1.195 Thigh angle 0.968 0.854 0.803 0.803 1 1.237 0.960 Calf angle 0.783 0.691 0.649 0.649 0.808 1 0.776 Elbow Angle 1.009 0.890 0.837 0.837 1.042 1.289 1

[0172] Elements satisfy:

[0173] X=(a ij ) n×n (i, j = 1, 2, ..., n), n represents the number of driving posture joint angles,

[0174] (2) Normalize the elements of each row of the judgment matrix X: First, calculate the sum of the elements of each row of the judgment matrix X: k represents the row number, and then the sum of the elements of each row of the judgment matrix X is normalized:

[0175]

[0176] (3) Based on the result after normalization, the sum of the elements in each row of the judgment matrix X is calculated, and the sum of the elements in each row is normalized, and the maximum eigenvalue and eigenvector are calculated.

[0177] Determine the sum of the elements in each row of the matrix X:

[0178] Normalized processing to get w i :

[0179] The process of finding the maximum eigenvalue and eigenvector satisfies: Aω=λ max ω, where ω represents the eigenvector, λ max represents the maximum characteristic root;

[0180] (4) Perform consistency check, the process includes:

[0181] Calculate the consistency index:

[0182] Find the corresponding average random consistency index RI, and calculate the consistency ratio based on the consistency index RI: CR = CI / RI.

[0183] (5) Determine whether the consistency ratio is less than 0.1. If so, receive the consistency test result and output the weights of each driving posture joint angle of the test driver. Otherwise, modify the judgment matrix X.

[0184] In this embodiment, through the above calculation process, the weights of the driving sitting joint angles of the test driver are output as shown in Table 4.

[0185] Table 4

[0186]

[0187] S103. For any driving posture joint angle A i , i = 1, ..., n, n represents the total number of driving posture joint angles. If the driving posture joint angle A i If the value of is within the comfort range obtained in Table 1, the comfort score of the driving sitting joint angle is recorded as 1; otherwise, the comfort score of the driving sitting joint angle is recorded as 0; add up all the comfort scores, and finally get the independent comfort score x of each driving sitting joint angle i ;

[0188] S104. Based on the weight of each driving posture joint angle and the independent comfort score x of each driving posture joint angle i , calculate the overall comfort score C of the driving sitting joint angle, the expression is:

[0189]

[0190] Among them, w i Represents the weight of each driving sitting posture joint angle of the test driver;

[0191] In addition, for any driving posture joint angle A i , the comfort score of each driving sitting posture joint angle is different (because of different weights), and some driving sitting posture joint angles must be in a comfortable state, then the possibility of the overall comfort score of the driving sitting posture is the permutation and combination of the independent comfort scores of each driving sitting posture joint angle, totaling 2 to the power of n possibilities, so that the overall comfort score after different driving sitting posture joint angle combinations is obtained, and at the same time, several groups of comfortable joint angles are formed, and the several groups of comfortable joint angles together constitute the comfortable joint angle combination library Deg, and the comfortable joint angle combination library Deg is shown in Table 5:

[0192] Table 5

[0193]

[0194] In step S2 of this embodiment, the selection process of the current group of comfortable joint angles is:

[0195] Calculate the overall comfort score of each group of comfortable joint angles in the comfortable joint angle combination library Deg;

[0196] The overall comfort score of each group of comfortable joint angles is sorted from high to low, and a group of comfortable joint angles is selected from the comfortable joint angle combination library Deg in the sorted order. As the current group of comfortable joint angles, j represents the group number of the selected comfortable joint angles. Table 5 shows several groups of comfortable joint angles in the comfortable joint angle combination library Deg. For example, the first group of comfortable joint angles includes all joint angles corresponding to A1 to A7, and the overall comfort score is 1. The second group of comfortable joint angles includes the driving posture joint angles corresponding to A1 to A6, but the driving posture joint angle corresponding to A7 is in the uncomfortable range, and the overall comfort score is 0.893; the third group of comfortable joint angles includes the driving posture joint angles corresponding to A1, A2, A3, A4, A5, and A7, and the overall comfort score is 0.867, and so on; the number of driving posture joint angles in the comfort range is large in the comfortable joints with the highest overall comfort score. When optimizing the cockpit parameters, it is initially ensured that the number of driver's sitting posture joint angles in the comfort range is as large as possible.

[0197] Entering the cockpit parameter optimization stage, in step S2, the cockpit parameters include: the horizontal distance L1 from the heel point to the R point, the horizontal distance L2 from the steering wheel center point to the R point, the vertical height H1 from the body floor to the R point, the vertical height H2 from the body floor to the steering wheel center point, the back angle A40, the pedal inclination angle A47, the initial value of the cockpit parameter is recorded as params0, and the cockpit parameter optimization model constructed is:

[0198] Objective function:

[0199]

[0200] Among them, A i represents the i-th driving posture joint angle of the test driver, angel_bound i Indicates the boundary value of the comfort interval corresponding to the i-th driving sitting posture joint angle of the test driver. The boundary value of the comfort interval includes the upper boundary value or the lower boundary value of the comfort interval. In specific implementation, angel_bound i The value of is determined by the distance of the driving sitting joint angle from the upper or lower boundary value of the comfort zone.

[0201] The cockpit parameters that can be set include:

[0202] The horizontal distance L1 from the heel point to the R point satisfies: L1min≤L1≤L1max, where L1max represents the maximum value of the horizontal distance L1 from the heel point to the R point, and L1min represents the minimum value of the horizontal distance L1 from the heel point to the R point;

[0203] The horizontal distance L2 from the center point of the steering wheel to the point R satisfies: L2min≤L2≤L2max, where L2max represents the maximum value of the horizontal distance L2 from the center point of the steering wheel to the point R, and L2min represents the minimum value of the horizontal distance L2 from the center point of the steering wheel to the point R;

[0204] The vertical height H1 from the vehicle body floor to the point R satisfies: H1min≤H1≤H1max, where H1max represents the maximum value of the vertical height H1 from the vehicle body floor to the point R, and H1min represents the minimum value of the vertical height H1 from the vehicle body floor to the point R;

[0205] The vertical height H2 from the vehicle body floor to the center point of the steering wheel satisfies: H2min≤H2≤H2max, where H2max represents the maximum value of the vertical height H2 from the vehicle body floor to the center point of the steering wheel, and H2min represents the minimum value of the vertical height H2 from the vehicle body floor to the center point of the steering wheel;

[0206] The back angle A40 satisfies: αmin≤A40≤αmax, where αmin represents the minimum value of the back angle A40 and αmax represents the maximum value of the back angle A40;

[0207] The pedal inclination angle A47 satisfies: βmin≤A47≤βmax, where βmin represents the minimum value of the pedal inclination angle A47, and βmax represents the maximum value of the pedal inclination angle A47;

[0208] Among them, the heel point refers to the heel point of the driver's right foot when the driver's right foot is placed on the floor and the accelerator pedal; the R point refers to the seat reference point; the back angle A40 refers to the angle between the back line and the vertical direction, and the pedal inclination angle A47 refers to the angle between the pedal plane and the horizontal direction;

[0209] Therefore, the constraints are:

[0210] L1min≤L1≤L1max;

[0211] L2min≤L2≤L2max;

[0212] H1min≤H1≤H1max;

[0213] H2min≤H2≤H2max;

[0214] αmin≤A40≤αmax;

[0215] βmin≤A47≤βmax.

[0216] In this embodiment, a cockpit parameter optimization model is constructed to fit the absolute distance between the cockpit parameters and the boundary values ​​of the comfort interval, and the objective function is to minimize the sum of the distances between all driving sitting posture joint angles in the selected current group of comfort joint angles and their corresponding comfort interval boundary values, so that each driving sitting posture joint angle under the current group of comfort joint angles is within the comfort interval.

[0217] See also Figure 7 In this embodiment, the trust region algorithm is used to solve the cockpit parameter optimization model. The trust region algorithm is a nonlinear optimization method that can ensure the global convergence of the optimization result. It is very simple and effective in solving constrained nonlinear minimum problems. The trust region algorithm is an iterative algorithm, that is, starting from a given initial solution, it is continuously improved through step-by-step iteration until a satisfactory approximate optimal solution is obtained. Its basic idea is to transform the optimization problem into a series of simple local optimization problems.

[0218] The basic idea of ​​the trust region algorithm is: at the current point x k A neighborhood around Ω k In the neighborhood Ω, a quadratic function q(s) that reflects the behavior of the objective function f(x) is used to approximate f(x). k It is called the trust region. The subproblem of the trust region algorithm is to find k Find the minimum point s of the approximate function q(s)k , this point is called the test step. k +s k )<f(x k ), then this iteration is considered successful. The current point x k It is updated to x k +s k , the current trust region Ω k Depending on the approximation of the quadratic function, choose to expand or keep it unchanged; otherwise it is judged as unsuccessful, and the current point x k Keep unchanged, the current trust region Ω k Zoom out. Mathematical definition of Ωk:

[0219] Ω k = {x∈R n |||xx k ||≤Δ k}

[0220] Where: Δ k ——trust region radius; ||.||——second-order norm; sk——must satisfy ||s k ||≤Δ k

[0221] In this embodiment, the cockpit parameters including the horizontal distance L1 from the heel point to the R point, the horizontal distance L2 from the steering wheel center point to the R point, the vertical height H1 from the vehicle body floor to the R point, the vertical height H2 from the vehicle body floor to the steering wheel center point, the back angle A40, and the pedal inclination angle A47 are used as optimization variables, and the optimization goal is to minimize de g1 The joint angle A i And the corresponding comfort zone boundary angel_bound i The algorithm stops when the adjustment of the variable is less than 1e-8 or the function change is less than 1e-8. For specific steps, see Figure 7 ,include:

[0222] (1) Set the initial iteration point x0, the initial trust region radius Δ0, the trust region radius adjustment threshold η1 = 0.25, η2 = 0.75, and the iteration accuracy ε = le-8;

[0223] (2) Calculate f(x) at x k The function value f(k) and gradient g(k) at ; if ||g(k)≤ε||, the iteration ends and the optimization result is output;

[0224] (3) Solve the following trust region algorithm subproblem:

[0225]

[0226] Where: H KRepresents the Hessian matrix, s = xx k , g k ——The gradient of the objective function f(x) at the current iteration point; obtain the solution S of the trust region subproblem k ;

[0227] According to the solution S of the trust region subproblem k Solve the approximation degree rk of the approximate model and the objective function:

[0228] The actual decrease of the objective function f(x) at step k is:

[0229] Ared k =f(x k )-f(x k +s k )

[0230] Approximate function q k (s) The predicted decrease at step k:

[0231] Pred k =q k (0)-q k (s k )

[0232] Define the ratio:

[0233] r k =Ared k / Pred k

[0234] r k To evaluate the approximation degree between the quadratic model and the objective function, r k The closer it is to 1, the closer the two are.

[0235] According to r k Determine the next iteration point x k+1 If r k >η1, then x k+1 =x k +s k , otherwise x k+1 =x k ;

[0236] Determine the trust region radius Δ for the next iteration based on rk k+1 :

[0237]

[0238] Go to step 2 and continue the subsequent iteration process until ||g k ||≤ε、Δ x≤ε or Δf≤ε, the iteration ends, the driving posture joint angle is output, and the optimal value of the cockpit parameters is obtained. The optimal value of the cockpit parameters currently solved by optimization is recorded as params j , params j It means solving a set of comfortable joint angles with the highest overall comfort score The corresponding cockpit parameter optimization model is the cockpit parameter optimization model obtained, params j Including the solved: the horizontal distance L1 from the heel point to point R j , horizontal distance from the center of the steering wheel to point R L2 j , the vertical height from the vehicle body floor to point R H1 j , the vertical height from the vehicle body floor to the center point of the steering wheel H2 j 、Back angle A40 j 、Pedal inclination A47 j .

[0239] Based on the global convergence of the trust region algorithm, an optimal value of the cockpit parameters params must be obtained during the solution process j , check the optimal value of cockpit parameters params j Are the corresponding driving posture joint angles all in the comfortable range? If the driving posture joint angles in the current group of comfortable joint angles cannot all be in the comfortable range, the next group of comfortable joint angles is reselected for cockpit parameter optimization to ensure that as many driving posture joint angles as possible are in the comfortable range under cockpit parameter optimization. The process of entering step S3 to determine whether all driving posture joint angles in the current group of comfortable joint angles under the optimal value of cockpit parameters are in the comfortable range is specifically as follows:

[0240] S31. Determine the optimal value of the cockpit parameters params obtained by the current optimization j Corresponding set of comfortable joint angles Whether all the values ​​of the driving posture joint angles in are within the comfort range, if so, executing step S4; otherwise, executing step S32;

[0241] S32. From the comfortable joint angle combination library Deg, select the next group of comfortable joint angles according to the overall comfort scores of all groups of comfortable joint angles from high to low Return to step S2; the comfortable joint angle The overall comfort score is less than the comfort joint angle Overall comfort score;

[0242] S33. Repeat steps S31 to S32 until a set of comfortable joint angles corresponding to the optimal values ​​of the cockpit parameters are optimized and solved. If all the driving posture joint angles are within the comfortable range, step S4 is executed.

[0243] In step S4, the cockpit parameter adjustment optimization model constructed includes:

[0244] Objective function:

[0245] min(params j -params0) 2

[0246] Constraints: The optimal values ​​of the cabin parameters params obtained in step S3 j The corresponding comfortable joint angle of group j constant.

[0247] See also Figure 8 In this embodiment, the simplex method is used to solve the cockpit parameter adjustment optimization model. The simplex method is a numerical method for finding the minimum or maximum value of the objective function in a multidimensional space. It is a heuristic search method (based on direct comparison of function values) and is usually applied to nonlinear optimization problems where the derivative may not be known.

[0248] For optimization problems with n variables, the n+1 variables are compared and iterated continuously by constructing n+1-dimensional simple geometric bodies, so that the internal space of the n+1-dimensional simple geometric body is continuously reduced, and finally the n+1 dimension is collapsed to n dimensions, i.e., the optimal variable. For this method, the optimization variables are the optimizable variables initially set by the user (combinations of L1, L2, H1, H2, A40, A47, etc.), and the optimization goal is to minimize the optimal value of the cockpit layout parameters params i The Euclidean distance from the initial setting parameter params0. The algorithm stops when the adjustment of the variable is less than 1e-8 or the function change is less than 1e-8.

[0249] The basic algorithm steps of the simplex method are as follows: (1) Sort by vertex values:

[0250] f(x1)≤f(x2)≤…≤f(x n+1 )

[0251] Checks whether the method should stop.

[0252] (2) Calculate x0, that is, except for x n+1 In addition, the center point (center of mass) of all points;

[0253] (3) Reflection: Calculate the reflection point x γ =x0+α(x0-x n+1 ) and α>0, if the reflection point is better than the second best but not better than the best, then a new point x is obtained by replacing the worst point n+1 With reflection point x γ, then continue with step (1);

[0254] (4) Extension: If the reflection point is the best point so far, f(x γ )≤f(x1), then calculate the extension point x e =x0+γ(x γ -x0) and γ>1. If the expansion point is better than the reflection point, f(x e )<f(x γ ) Then obtain a new point x by replacing the worst point n+1 With extension point x e , then continue with step 1, otherwise obtain a new point x by replacing the worst point n+1 With reflection point x γ , then continue with step (1)

[0255] (5) Contraction: One thing is certain: f(x γ )≥f(x n ). If f(x γ )<f(x n+1 ), and then calculate the external contraction point x c =x0+ρ(x γ -x0)(0<ρ<0.25); if the contraction point is better than the reflection point, that is, f(x c )<f(x γ ), and then obtain a new point x by replacing the worst point n+1 With the contraction point x c And continue with step (1); otherwise, proceed to step (6);

[0256] (6) Replace all points x1 and x2 except the optimal point i =x1+σ(x i -x1) and go to step (1);

[0257] Among them, α, γ, ρ and σ are respectively the reflection coefficient, expansion coefficient, contraction coefficient 1 and contraction coefficient 2. The standard values ​​are α=1, γ=2, ρ=1 / 2 and σ=1 / 2.

[0258] In this embodiment, the optimal value of the cockpit parameter params i Minimize the Euclidean distance from the initial value of the cockpit parameters and take the optimal value of the cockpit parameters params j The corresponding comfortable joint angle of group j The constraint condition is unchanged to ensure that after the cockpit parameters are adjusted, the number of driving posture joint angles in the comfortable range does not change, so that the number of driving posture joint angles in the comfortable range after the cockpit parameters are optimized is as large as possible while the cockpit parameter adjustment is minimized. The above process is integrated as a whole, and the detailed execution flow chart can be seen in Fig. 9.

[0259] like Fig.10 As shown, this embodiment proposes a cockpit parameter optimization system for improving the driver's sitting comfort. The system is used to implement the cockpit parameter optimization method for improving the driver's sitting comfort described in the above embodiment. The system includes:

[0260] A comfortable joint angle combination library construction unit is used to construct a comfortable joint angle combination library; the comfortable joint angle combination library is provided with a plurality of groups of comfortable joint angles, each group of comfortable joint angles includes a plurality of driving sitting posture joint angles, and each driving sitting posture joint angle has a corresponding comfort interval;

[0261] The cockpit parameter optimization unit takes the minimum sum of distances between all driving posture joint angles in the current group of comfortable joint angles and their corresponding comfort interval boundary values ​​as the objective function, takes the set cockpit parameter range as the constraint condition, builds and solves the cockpit parameter optimization model, and obtains the optimal value of the cockpit parameters;

[0262] The comfort interval verification unit is used to determine whether each driving posture joint angle in the current group of comfortable joint angles under the optimal value of the cockpit parameters is in the comfort interval. If so, the optimal value of the cockpit parameters is output; otherwise, the next group of comfortable joint angles is selected and input into the cockpit parameter optimization unit for cockpit parameter optimization;

[0263] The cockpit parameter adjustment optimization unit takes the minimum Euclidean distance between the optimal value of the cockpit parameter and the initial value of the cockpit parameter as the objective function, and takes the unchanged comfort joint angle of the current group under the optimal value of the cockpit parameter as the constraint condition. The cockpit parameter adjustment optimization model is constructed and solved to obtain the optimal value of the adjusted cockpit parameters.

[0264] See also Fig.11 This embodiment proposes an electronic device, including a memory 101, a processor 102, and a computer program stored in the memory 101 and running on the processor 102, wherein when the processor 102 executes the computer program, the steps of the cockpit parameter optimization method for improving the sitting comfort of the driver are implemented.

[0265] In this embodiment, the processor 102 may include a CPU or a specific integrated circuit, or be configured to implement one or more integrated circuits of this embodiment, and the memory 101 may include a large-capacity memory for data or instructions. It may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, the memory 101 may include a removable or non-removable (or fixed) medium. In appropriate cases, the memory 101 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 101 is a non-volatile solid-state memory.

[0266] The memory 101 may include a read-only memory (ROM), a random access memory (RAM), a disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Therefore, typically, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the steps of implementing the target detection method proposed in this embodiment.

[0267] This embodiment also proposes a computer storage medium, which stores a computer program. The computer program is executed by a processor to implement the steps of the cockpit parameter optimization method for improving the sitting comfort of the driver.

[0268] The above embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Any equivalent substitution or change made by a person skilled in the art based on the present invention is within the protection scope of the present invention.

Claims

1. A cockpit parameter optimization method for improving the driver's sitting comfort, characterized in that: The following steps are involved: S1. Constructing a comfortable joint angle combination library; the comfortable joint angle combination library is provided with several groups of comfortable joint angles, each group of comfortable joint angles includes several driving sitting posture joint angles, and each driving sitting posture joint angle has a corresponding comfort interval; S2. Taking the minimum sum of distances between all driving posture joint angles in the current group of comfortable joint angles and their corresponding comfort interval boundary values ​​as the objective function, and taking the set cockpit parameter range as the constraint condition, a cockpit parameter optimization model is constructed and solved to obtain the optimal value of the cockpit parameters; S3. Determine whether all the driving posture joint angles in the current group of comfortable joint angles under the optimal value of the cockpit parameters are in the comfortable range. If so, output the optimal value of the cockpit parameters and execute step S4; otherwise, select the next group of comfortable joint angles and return to step S2; S4. Taking the minimum Euclidean distance between the optimal value of the cockpit parameters and the initial value of the cockpit parameters as the objective function, and taking the unchanged comfort joint angle of the current group under the optimal value of the cockpit parameters as the constraint condition, the cockpit parameter adjustment optimization model is constructed and solved to obtain the optimal value of the adjusted cockpit parameters.

2. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 1, characterized in that: The plurality of driving sitting posture joint angles include: elbow angle, shoulder angle, neck angle, back angle, hip angle, thigh angle and calf angle.

3. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 2 is characterized in that: The process of obtaining the comfort zone is as follows: Select a number of test drivers and different car models for testing; Based on the limb size of the test driver, the analytical calculation model of the sitting posture joint angle is used to obtain the value of the test driver's driving sitting posture joint angle, and the comfortable range and uncomfortable range corresponding to different driving sitting posture joint angles are screened out; Based on the comfortable range and uncomfortable range corresponding to the driving sitting posture joint angle, several groups of driving sitting posture joint angle grading evaluation data made by the test drivers facing different car models are obtained; The driving sitting posture joint angle grading evaluation data is processed to obtain the comfort ranges of various driving sitting posture joint angles of test drivers of different genders and heights under tests of different vehicle models.

4. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 3 is characterized in that: The process of screening out the comfortable range and uncomfortable range corresponding to the driving sitting posture joint angle is as follows: Ask test drivers of different genders and heights to rate the comfort of the sitting joint angle when facing different models. The interval of the joint angle where the comfort score exceeds the set comfort score threshold is determined as the comfortable interval corresponding to the driving sitting joint angle, and the interval of the joint angle where the comfort score is less than the set comfort score threshold is determined as the uncomfortable interval corresponding to the driving sitting joint angle. According to the combinations of different genders, different heights and different car models, several groups of driving posture joint angle grading evaluation data are obtained.

5. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 3 is characterized in that: When processing the driving posture joint angle grading evaluation data, the data in the first 15% to 35% and the last 15% to 35% of the driving posture joint angle grading evaluation data are eliminated; the value of each driving posture joint angle corresponding to the optimal evaluation data in the first 15% to 35% interval is used as the lower boundary value of the comfort range corresponding to each driving posture joint angle, and the value of each driving posture joint angle corresponding to the optimal evaluation data in the last 15% to 35% interval is used as the upper boundary value of the comfort range corresponding to each driving posture joint angle.

6. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 4, characterized in that: The process of constructing the comfortable joint angle combination library described in step S1 is as follows: The test drivers were asked to rate the importance of different driving posture joint angles based on their subjective feelings of comfort; Based on the test drivers' scores on the importance of different driving sitting posture joint angles, the average importance of different driving sitting posture joint angles was calculated, and the average importance was used as the scale of the hierarchical analysis method. The weights of each driving sitting posture joint angle of the test drivers were obtained by using the hierarchical analysis method. For any driving posture joint angle A i , i = 1, ..., n, n represents the total number of driving posture joint angles. If the driving posture joint angle A i If the value of is within the comfortable range, the comfort score of the driving sitting joint angle is recorded as 1; Otherwise, the comfort score of the driving sitting posture joint angle is recorded as 0; all comfort scores are added together to finally obtain the independent comfort score x of each driving sitting posture joint angle i ; According to the weight of each driving posture joint angle and the independent comfort score x of each driving posture joint angle i , calculate the overall comfort score C of the driving sitting joint angle, the expression is: Among them, w i Represents the weight of each driving sitting posture joint angle of the test driver; The independent comfort scores of various driving sitting posture joint angles are arranged and combined to obtain the overall comfort score after different driving sitting posture joint angle combinations, and at the same time, several groups of comfortable joint angles are formed, and the several groups of comfortable joint angles together constitute the comfortable joint angle combination library Deg.

7. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 6, characterized in that: In step S2, the selection process of the current group of comfortable joint angles is: Calculate the overall comfort score of each group of comfortable joint angles in the comfortable joint angle combination library Deg; The overall comfort score of each group of comfortable joint angles is sorted from high to low, and a group of comfortable joint angles d is selected from the comfortable joint angle combination library Deg in the sorted order. egj As the current group of comfortable joint angles, j represents the group number of the selected comfortable joint angles.

8. The cockpit parameter optimization method for improving the driver's sitting comfort according to any one of claims 1 to 7, characterized in that: In step S2, the cockpit parameters include: the horizontal distance L1 from the heel point to the R point, the horizontal distance L2 from the steering wheel center point to the R point, the vertical height H1 from the vehicle body floor to the R point, the vertical height H2 from the vehicle body floor to the steering wheel center point, the back angle A40, the pedal inclination angle A47, the initial value of the cockpit parameters is recorded as params0, and the cockpit parameter optimization model is: Objective function: Among them, A i represents the i-th driving posture joint angle of the test driver, angel_bound i represents the boundary value of the comfort interval corresponding to the i-th driving sitting posture joint angle of the test driver, and the boundary value of the comfort interval is the upper boundary value or the lower boundary value of the comfort interval; The cockpit parameter ranges include: The horizontal distance L1 from the heel point to the R point satisfies: L1min≤L1≤L1max, where L1max represents the maximum value of the horizontal distance L1 from the heel point to the R point, and L1min represents the minimum value of the horizontal distance L1 from the heel point to the R point; The horizontal distance L2 from the center point of the steering wheel to the point R satisfies: L2min≤L2≤L2max, where L2max represents the maximum value of the horizontal distance L2 from the center point of the steering wheel to the point R, and L2min represents the minimum value of the horizontal distance L2 from the center point of the steering wheel to the point R; The vertical height H1 from the vehicle body floor to the point R satisfies: H1min≤H1≤H1max, where H1max represents the maximum value of the vertical height H1 from the vehicle body floor to the point R, and H1min represents the minimum value of the vertical height H1 from the vehicle body floor to the point R; The vertical height H2 from the vehicle body floor to the center point of the steering wheel satisfies: H2min≤H2≤H2max, where H2max represents the maximum value of the vertical height H2 from the vehicle body floor to the center point of the steering wheel, and H2min represents the minimum value of the vertical height H2 from the vehicle body floor to the center point of the steering wheel; The back angle A40 satisfies: αmin≤A40≤amax, where αmin represents the minimum value of the back angle A40, and αmax represents the maximum value of the back angle A40; The pedal inclination angle A47 satisfies: βmin≤A47≤βmax, where βmin represents the minimum value of the pedal inclination angle A47, and βmax represents the maximum value of the pedal inclination angle A47; Among them, the heel point refers to the heel point of the driver's right foot when the driver's right foot is placed on the floor and the accelerator pedal; the R point refers to the seat reference point; the back angle A40 refers to the angle between the back line and the vertical direction, and the pedal inclination angle A47 refers to the angle between the pedal plane and the horizontal direction; Therefore, the constraints are: L1min≤L1≤L1max; L2min≤L2≤L2max; H1min≤H1≤H1max; H2min≤H2≤H2max; αmin≤A40≤αmax; βmin≤A47≤βmax.

9. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 8, characterized in that: The method for solving the cockpit parameter optimization model is the trust region algorithm to obtain the optimal value of the cockpit parameters. The optimal value of the cockpit parameters currently solved by optimization is recorded as params j , params j It means to solve the set of comfortable joint angles d with the highest overall comfort score. egj The corresponding cockpit parameters obtained by the cockpit parameter optimization model, params j Including the solved: the horizontal distance L1 from the heel point to point R j , horizontal distance from the center of the steering wheel to point R L2 j , the vertical height from the vehicle body floor to point R H1 j , the vertical height from the vehicle body floor to the center point of the steering wheel H2 j 、Back angle A40 i 、Pedal inclination A47 j .

10. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 9, characterized in that: In step S3, the process of judging whether all the driving posture joint angles in the current group of comfortable joint angles under the optimal value of the cockpit parameters are in the comfortable range is as follows: S31. Determine the optimal value of the cockpit parameters params obtained by the current optimization j The corresponding set of comfortable joint angles d egj Are all the values ​​of the driving posture joint angles in the comfortable range? If so, execute step S4; Otherwise, execute step S32; S32. From the comfortable joint angle combination library Deg, select the next group of comfortable joint angles according to the overall comfort scores of all groups of comfortable joint angles from high to low Return to step S2; the comfortable joint angle The overall comfort score is less than the comfort joint angle Overall comfort score; S33. Repeat steps S31 to S32 until a set of comfortable joint angles corresponding to the optimal values ​​of the cockpit parameters are optimized and solved. If all the driving posture joint angles in the figure are within the comfortable range, step S4 is executed.

11. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 9, characterized in that: The cockpit parameter adjustment optimization model constructed in step S4 includes: Objective function: min(params j -params0) 2 Constraints: The optimal values ​​of the cabin parameters params obtained in step S3 j The corresponding current group comfortable joint angle d egj constant.

12. The cockpit parameter optimization method for improving the driver's sitting comfort according to claim 11, characterized in that: The solution method for the cockpit parameter adjustment optimization model is the simplex method.

13. A cockpit parameter optimization system for improving the driver's sitting comfort, characterized in that: The system is used to implement the cockpit parameter optimization method for improving the driver's sitting comfort according to any one of claims 1 to 7 and 9 to 12, and the system comprises: A comfortable joint angle combination library construction unit is used to construct a comfortable joint angle combination library; the comfortable joint angle combination library is provided with a plurality of groups of comfortable joint angles, each group of comfortable joint angles includes a plurality of driving sitting posture joint angles, and each driving sitting posture joint angle has a corresponding comfort interval; The cockpit parameter optimization unit takes the minimum sum of distances between all driving posture joint angles in the current group of comfortable joint angles and their corresponding comfort interval boundary values ​​as the objective function, takes the set cockpit parameter range as the constraint condition, builds and solves the cockpit parameter optimization model, and obtains the optimal value of the cockpit parameters; The comfort interval verification unit is used to determine whether each driving posture joint angle in the current group of comfortable joint angles under the optimal value of the cockpit parameters is in the comfort interval. If so, the optimal value of the cockpit parameters is output; otherwise, the next group of comfortable joint angles is selected and input into the cockpit parameter optimization unit for cockpit parameter optimization; The cockpit parameter adjustment optimization unit takes the minimum Euclidean distance between the optimal value of the cockpit parameter and the initial value of the cockpit parameter as the objective function, and takes the unchanged comfort joint angle of the current group under the optimal value of the cockpit parameter as the constraint condition. The cockpit parameter adjustment optimization model is constructed and solved to obtain the optimal value of the adjusted cockpit parameters.

14. An electronic device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the steps of the method for optimizing the cockpit parameters for improving the sitting comfort of the driver as described in any one of claims 1 to 7 and 9 to 12 are implemented.

15. A computer storage medium, characterized in that The computer storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the cockpit parameter optimization method for improving the driver's sitting comfort as described in any one of claims 1 to 7 and 9 to 12.

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