Modular design method for car eye ellipse and head envelope

Abstract

The application discloses a modular design method for automobile eye ellipse and head envelope, and is characterized in that, based on the secondary development function of CATIA software, a knowledge engineering template file (part file) capable of directly displaying a design target structure is established, a plurality of fixed input parameters, a plurality of variable parameters and intermediate parameters are selected, the corresponding relationship between each parameter and an output parameter is automatically converted and associated, and an intelligent design template for automobile eye ellipse and head envelope is obtained; then, the template is called during design, different variable parameter information is input according to design requirements, the knowledge engineering template is automatically run, and the calculated output parameter is directly displayed in the form of a graph. The application can simplify the calculation process, reduce repetitive labor, avoid human calculation errors, improve design accuracy, and better improve design efficiency and accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automobile vehicle design, and particularly relates to a modular design method for an eye ellipse and a head envelope of an automobile. BACKGROUND

[0002] The eye ellipse is a statistical distribution graph of the position of the eyes of a driver of an automobile specified in the standard SAE J 941 Motor Vehicle Drivers' Eye Locations, and is used for checking the field of view of the driver. The head envelope is a region of the position of the head of a driver and a passenger of an automobile specified in the standard SAE J1052 Motor Vehicle Driver and Passenger Head Position, and is used for checking the space between the head of the driver and the passenger and the surrounding components in the design of the automobile.

[0003] The eye ellipse and the head envelope are very important design references. In the initial stage of the design of the automobile, that is, in the stage in which the position of the driver and the passenger is initially determined and the modeling has not yet started, the eye ellipse and the head envelope of the driver need to be made, which are used for constraining the modeling design and checking the field of view. The eye ellipse and the head envelope change with the change of the position of the human body. With the improvement of the design, the position of the human body needs to be adjusted many times, so that the position of the eye ellipse and the head envelope also needs to be changed. The conventional method for making the eye ellipse and the head envelope is relatively cumbersome. The design engineer needs to be very familiar with the steps for making the eye ellipse in the standard SAE J941 and the steps for making the head envelope in the standard SAE J1052, which takes a long time, which increases the workload of the design engineer and is not efficient, and it is difficult to keep up with the pace of the development of the whole vehicle design.

[0004] According to the standard SAE J 941, the steps for making the eye ellipse of the driver of a class A vehicle by using the conventional design method are as follows:

[0005] (1) Find the design reference points: AHP point, H point, SWC point:

[0006] The AHP point (Accelerator Heel Point) is defined in item 3.5.1 of SAE J1100, that is, the heel point of the accelerator pedal, which is the contact point between the sole of the shoe model of the H point device and the surface of the accelerator pedal when the ankle angle is 87°, and the contact point between the heel and the floor. See the attached figure. Figure 6 .

[0007] H-point, i.e. the cross point, SAE J 1100 3.4.5, or SAE J826, H-point is the intersection of the thigh line and the torso line, in the vehicle design, H-point coincides with SgRP point (R point), which can be used as a vehicle reference point. See attached Figure 6 .

[0008] SWC point, i.e. the center point of the steering wheel, SAE J 1100 3.3.22, the front wheel is in the vertical forward position, and theoretically the angle between the steering column and the plane tangent to the steering wheel rim is a reference point of the vehicle. See attached Figure 6 .

[0009] In vehicle design, AHP point, H point, SWC point are the first defined design reference points, this paper does not discuss the positioning method of these three points, only discusses how to make the driver's eye ellipse and head envelope after the three reference points are known.

[0010] (2) Make A47 parameter and determine the value:

[0011] "A47": SAE J 1100 defines the angle between the driver's shoe plane and the horizontal plane, which is generally the angle between the driver's foot pedal and the horizontal plane when the driver steps on the accelerator pedal. The angle is generally greater than 0° but not more than 90°.

[0012] (3) Make BOFRP point (Ball of Foot Reference Point), i.e. a vehicle reference point consistent with the position of the driver's BOF point specified in SAE J 1100 3.5.3. And BOF point (Ball of Foot) is defined in SAE J 1100 3.5.2 as a point 203mm away from the HOS point on the side surface center of the shoe model.

[0013] Make BOFRP point according to AHP point and A47 angle, see attached Figure 6 . The distance between BOFRP point and AHP point is 203mm, and the angle with the horizontal is A47.

[0014] (4) According to AHP point, H point, SWC point in step (1), and BOFRP point in step (3), determine the values of related parameters: W20, H30, H8, L6, L1;

[0015] Among them:

[0016] W20: SAE J 1100 defines SgRP point Y coordinate. See attached Figure 7 .

[0017] H30: Seat height, dimension specified in SAE J 1100, generally refers to the vertical distance from the SgRP point to the AHP point. See Appendix Figure 6 .

[0018] H8: Defined in SAE J 1100 as the Z coordinate of the AHP point. See Appendix Figure 6 .

[0019] L6: Defined in SAE J 1100 as the horizontal distance from the BOFRP point to the center point of the steering wheel. See Appendix Figure 6 .

[0020] L1: Defined in SAE J 1100 as the X coordinate of the BOFRP point. See Appendix Figure 6 .

[0021] (5) Determine the value of t according to the percentage of vehicles containing clutch pedal in the production vehicles, if 50% or more vehicles use clutch pedal, then t is 1, otherwise 0; wherein t is the coefficient of the formula representing the clutch pedal state.

[0022] (6) Determine the center position of the eye ellipse according to the formulas 2, 3, 4, 5 in the standard SAE J 941 4.3, the calculation formulas are as follows:

[0023] Xc = L1 + 664 + 0.587 (L6) - 0.176 (H30) - 12.5t (2)

[0024] Ycl = W20 - 32.5 (3)

[0025] Ycr = W20 + 32.5 (4)

[0026] Zc = H8 + 638 + H30 (5)

[0027] (7) Make the eye ellipse center point: make the left eye ellipse center point with the Xc, Ycl, Zc values obtained in step (6), and make the right eye ellipse center point with the Xc, Ycr, Zc values obtained in step (6).

[0028] (8) Determine whether the value of TL23 is greater than 133mm or less than 133mm according to the driver seat slide rail stroke of the production vehicle, the value range determines the selection of the eye ellipse axis length.

[0029] (9) According to SAE J941 4.1 (see Figure 3According to the provisions of SAE J941 4.2, the axis length of the left eye ellipse is obtained according to the seat adjustment stroke (TL23) and the corresponding human body percentile (95, 99), and the left eye ellipse X axis, Y axis and Z axis are drawn with the left eye ellipse center point obtained in step (7) as the origin. According to the provisions of SAE J941 4.2, the X axis has a forward inclination angle β (equation 1: β = 12 deg) relative to the horizontal plane

[0030] (10) According to the Z axis length in step (9), a sphere is made with the left eye ellipse center point as the center, and is named as sphere 1.

[0031] (11) According to the sphere 1 in step (10), the left eye ellipse surface is made with the left eye ellipse center point as the origin, and with the three axes (X axis, Y axis and Z axis) of the eye ellipse in step (9) by using the affine command of CATIA software.

[0032] (12) The left eye ellipse surface in step (11) is translated from the left eye ellipse center point to the right eye ellipse center point by using point-to-point translation, and the right eye ellipse surface is obtained.

[0033] The above is the traditional method for making the driver's eye ellipse.

[0034] According to the provisions of SAE J1052, in the case of known eye ellipse center point, the method for making the head envelope of the driver of a class A vehicle by using the traditional design method is as follows:

[0035] (1) In the case of known eye ellipse center point, the eye ellipse centroid point is made, which is the midpoint of the left and right eye ellipse center points.

[0036] (2) The head envelope ellipsoid centroid point is made with the eye ellipse centroid point as the origin. The deviation value of the two points follows the provisions of SAE J1052 7.1 (see Figure 4 ).

[0037] (3) The head envelope X axis, Y axis and Z axis are made with the head envelope centroid point as the origin. The lengths of the three axes need to follow the provisions of SAE J1052 6.1 (see Figure 5 ), wherein the value of TL23 is the same as that of the eye ellipse, the human body percentile can be selected as 95 or 99, and the axis length values are different.

[0038] (4) According to the provisions of SAE J1052 4.1, the head envelope of the driver of a class A vehicle has a forward inclination angle (parameter β), TL23 is not 0, and the inclination angle is 12°; TL23 is 0, and there is no inclination angle. Generally, the driver's seat has a slide rail, so the inclination angle of the head envelope X axis in the above step (3) is 12°.

[0039] (5) According to the Z semi-axis obtained in step (3), a circle ball is made with the head envelope center point obtained in step (2) as the circle point;

[0040] (6) The circle ball in step (5) is subjected to affine with the head envelope three-coordinate axes (X axis, Y axis, Z axis) in step (3), so that a complete ellipsoidal ball is obtained;

[0041] (7) The ellipsoidal ball in step (6) is divided into upper and lower hemispheres by the plane formed by the X axis and the Y axis with a 12° forward inclination obtained in step (4), and the lower hemisphere is discarded and the upper hemisphere is retained;

[0042] (8) The upper hemisphere in step (7) is divided into left and right hemisurfaces by the plane formed by the X axis and the Z axis obtained in step (3), the half surface on the outer side (negative direction of the Y axis) is offset by 23 mm in the negative direction of the Y axis, and a splicing surface is made between the unshifted surface and the surface offset by 23 mm, and the unshifted surface, the surface offset by 23 mm and the splicing surface are fitted into an integral surface, that is, the head envelope is obtained.

[0043] From the above steps of making the eye ellipse and the head envelope, it can be seen that the traditional method of making the eye ellipse and the head envelope has many steps, the designer needs to calculate according to the size relationship of the graphic shape, needs to refer to the standard table for judgment, and needs to calculate according to the standard formula; therefore, the operation is complicated, the time is spent more, the calculation is easy to make mistakes, and the efficiency is low.

[0044] In the prior art, some software modules are used to modularize the calculation process, but only software modules are used to separately calculate the eye ellipse or separately calculate the head envelope. The design methods of the eye ellipse and the head envelope have similarities, the centroid point of the eye ellipse is the reference point of the centroid point of the head envelope, so the applicant considers that the two can be designed together as a module. Therefore, the design process can be better simplified and the design efficiency can be improved by utilizing the large number of parameters that are the same or related. SUMMARY

[0045] In view of the above problems of the prior art, the technical problem to be solved by the present application is how to provide a modular design method for the eye ellipse and the head envelope of a vehicle, which can better simplify the calculation process, reduce errors caused by repeated calculations, and better improve the design efficiency and accuracy.

[0046] In order to solve the above technical problems, the present application adopts the following technical scheme:

[0047] A modular design method for the eye ellipse and the head envelope of a vehicle, characterized in that it comprises the following steps:

[0048] Step A: based on the secondary development function of CATIA software, a knowledge engineering template file (part file) capable of directly displaying the design target structure is established, and AHP point, H point and SWC point are taken as fixed input parameter information; "TL23", "A47", "human body percentile" and "clutch pedal state" are taken as variable parameter information; "H30", "W20", "L6", "L1", "H8", "β", "t", "eye ellipse X axis length", "eye ellipse Y axis length", "eye ellipse Z axis length", "Xh", "Zh", "head package X axis length", "head package Y axis length" and "head package Z axis length" are taken as intermediate parameters; left and right eye ellipses, left and right eye ellipse center points and head envelope are taken as output parameter information, the corresponding relationship between the input parameter information, the intermediate parameter information and the output parameter information is established in the knowledge engineering template file, and automatic conversion association is realized; an intelligent design template of automobile eye ellipse and head envelope is obtained;

[0049] Step B: the intelligent design template of automobile eye ellipse and head envelope established in step A is called in CATIA software, different variable parameter information is input according to the design requirement, and the knowledge engineering template automatically runs and directly displays the calculated output parameters in the form of graphics.

[0050] The method utilizes the secondary development function of CATIA software, pre-sets the corresponding relationship between the input parameters and the output parameters in the knowledge engineering template file, establishes the corresponding model, so that only the input parameter information that needs to be adjusted needs to be input during design, and the corresponding automobile eye ellipse and head envelope graphics can be automatically calculated and output by the model. The designer can quickly adjust the input parameters and obtain the automobile eye ellipse and head envelope graphics corresponding to the input parameters in real time. Specifically, in the scheme, the common input parameters required for automobile eye ellipse and head envelope design are selected, and then appropriate intermediate parameters are selected, so that the corresponding geometric figures are changed by the input parameters and the intermediate parameters, and the automatic conversion association between the input parameters, the intermediate parameters and the output parameters is realized. In this way, only the preset engineering template file needs to be called during design, and the calculation results of the corresponding automobile eye ellipse and head envelope graphics generated following the change of the input information of the variable parameters can be realized. Therefore, the method can simplify the calculation process, reduce repetitive labor, avoid human calculation errors, improve design accuracy, and better improve design efficiency and accuracy.

[0051] Further, step A specifically includes the following steps:

[0052] 1) Open CATIA software, establish a knowledge engineering template file (part file) which can visually display the design target structure, establish a horizontal coordinate system in the template file, the coordinate system is a horizontal coordinate system, the direction of X coordinate is set along the length direction of the vehicle, the direction of Y coordinate is set along the width direction of the vehicle, and the direction of Z coordinate is set along the height direction of the vehicle; then establish design reference points as fixed input parameters in the coordinate system: AHP point, H point and SWC point;

[0053] 2) Establish variable parameters to be input: "TL23", "A47", "human body percentile" and "clutch pedal state", according to the value range of the variable parameters, assign values to the parameters to be input in step 2);

[0054] Among them:

[0055] "TL23": refers to the length from SgRP (seat reference point) to FDH (the most forward design H point), generally distinguished by range, "TL23">133mm, "TL23" <133mm or "TL23" =0mm (at this time, it is a fixed seat);

[0056] "A47": refers to the angle between the driver's shoe plane and the horizontal plane defined in SAE J 1100, which is generally the angle between the driver's foot and the horizontal plane when stepping on the accelerator pedal; the value range is 0-90°;

[0057] "Human body percentile": human body measurement language, used to determine the distribution value of human body size, human body percentile represents that the person with a certain human body size and less than the size accounts for a percentage of the total number of statistical objects; (taking the 95th percentile, human body height size as an example, it means that 95% of people are equal to or less than the size) SAE J 941 and SAE J 1052 only define 95 and 99 percentile human bodies, that is, the value at this place is 95 or 99;

[0058] "Clutch pedal state": multi-value parameter, divided into having clutch pedal and not having clutch pedal, represented as coefficient t in the calculation formula, the percentage of vehicles containing clutch pedal in production vehicles determines the value of t, if 50% or more vehicles use clutch pedal, t takes 1, otherwise, t takes 0;

[0059] 3) Make BOFRP point: make BOFRP point according to the assigned AHP point in the foregoing step and the defined A47 value, the distance between BOFRP point and AHP point is 203mm, and the angle with the horizontal is A47;

[0060] 4) Establish intermediate parameters "H30", "W20", "L6", "L1" and "H8";

[0061] According to the AHP point, H point, SWC point and BOFRP point determined in the preceding steps, the value of the intermediate parameter is determined according to the definition of the intermediate parameter;

[0062] W20: SAE J 1100 defines the Y coordinate of the SgRP point;

[0063] H30: Seat height, SAE J 1100 specifies the size, which refers to the vertical distance from the SgRP point to the AHP point;

[0064] H8: SAE J 1100 defines the Z coordinate of the AHP point;

[0065] L6: SAE J 1100 defines the horizontal distance between the BOFRP point and the center point of the steering wheel;

[0066] L1: SAE J 1100 defines the X coordinate of the BOFRP point;

[0067] 5) Establish the intermediate parameter "β";

[0068] According to SAE J 941 4.2, the X axis of the driver's eye ellipse of a Class A vehicle has a forward inclination angle β, Equation 1: β = 12 deg;

[0069] According to SAE J 1052 4.1, the head envelope of a Class A vehicle driver has a forward inclination angle β, the value of which is related to TL23; if TL23 is not 0, the inclination angle is 12 deg; if TL23 is 0, there is no inclination angle;

[0070] Using the rule method of the CATIA knowledge engineering module, associate TL23 in the preceding steps with β, and if TL23 is not 0, β = 12 deg;

[0071] 6) Establish the intermediate parameter "t"; and use the rule method of the knowledge engineering module to establish the corresponding relationship between the value of t and the "clutch pedal state" parameter in the preceding steps using VB language; if 50% or more of the vehicles use the clutch pedal, t takes 1, otherwise t takes 0;

[0072] 7) Make the parameterized eye ellipse center point:

[0073] Refer to Equations 2, 3, 4 and 5 (from SAE J 941 4.3):

[0074] Xc = L1 + 664 + 0.587 (L6) - 0.176 (H30) - 12.5t (2)

[0075] Yc1 = W20 - 32.5 (3)

[0076] Ycr = W20 + 32.5 (4)

[0077] Zc = H8 + 638 + H30 (5);

[0078] Wherein the three coordinates of the left eye ellipse center point are Xc, Ycl, Zc (equation 2, equation 3, equation 5), and the three coordinates of the right eye ellipse center point are Xc, Ycr, Zc (equation 2, equation 4, equation 5). The values of the eye ellipse center point coordinates are calculated by substituting the values obtained in the foregoing steps into the equations.

[0079] 8) Establish intermediate parameters: "eye ellipse X-axis length", "eye ellipse Y-axis length", and "eye ellipse Z-axis length";

[0080] According to the provisions of Clause 4.1 of the standard SAE J941 (see Figure 3 ), the selection rules for the eye ellipse axis length are edited using VB language by applying the rule method of the knowledge engineering module. The established "TL23", "human body percentile", and the three parameters "eye ellipse X-axis length", "eye ellipse Y-axis length", and "eye ellipse Z-axis length" are associated, so that the three parameters "eye ellipse X-axis length", "eye ellipse Y-axis length", and "eye ellipse Z-axis length" have corresponding values according to "TL23" and "human body percentile";

[0081] 9) Make eye ellipse three-coordinate axes;

[0082] Take the left eye ellipse center point obtained in step 7 as the origin, and take the three parameters "eye ellipse X-axis length", "eye ellipse Y-axis length", and "eye ellipse Z-axis length" in step 8 to make the left eye ellipse X-axis, Y-axis, and Z-axis, wherein the angle between the X-axis and the horizontal plane is β;

[0083] 10) According to the length of the eye ellipse Z-axis in step 9), make a spherical surface with the left eye ellipse center point as the center and name it as spherical surface 1;

[0084] 11) According to the spherical surface 1 in step 10), make a left eye ellipse surface with the left eye ellipse center point as the origin and the three coordinate axes (X-axis, Y-axis, Z-axis) in step 9) by using the affine command of CATIA software;

[0085] 12) Translate the left eye ellipse surface in step 11) from the left eye ellipse center point to the right eye ellipse center point by using the point-to-point translation method to obtain the right eye ellipse surface;

[0086] 13) Make an eye ellipse centroid point: the eye ellipse centroid point is the midpoint of the left and right eye ellipse center points; according to the left and right eye ellipse center points obtained in step 8), make a centroid point located between the two points; this point is the reference point of the centroid point of the head envelope ellipsoid.

[0087] 14) Establish intermediate parameters: "Xh", "Zh";

[0088] According to the provisions of SAE J 1052 7.1 (see Figure 4 ), the rule method of the knowledge engineering module is applied, the head envelope centroid point offset rule is edited in VB language, and the corresponding values of TL23 in different ranges in the table are assigned to "Xh" and "Zh";

[0089] 15) Take the eye ellipse centroid point in step 14) as the reference point, and make the head envelope ellipse centroid point according to the three-coordinate reference point method, the X value of which is "Xh", the Y value is 0, and the Z value is "Zh";

[0090] 16) Establish intermediate parameters: "head package X axis length", "head package Y axis length", and "head package Z axis length";

[0091] According to the provisions of SAE J1052 6.1 (see Figure 5 ), the rule method of the knowledge engineering module is applied, the head envelope axis length rule is edited in VB language, and "TL23", "human body percentile", and "head package X axis length", "head package Y axis length", "head package Z axis length" are associated, so that "head package X axis length", "head package Y axis length", "head package Z axis length" have corresponding values according to "TL23" and "human body percentile";

[0092] 17) Make the head envelope X axis, Y axis, and Z axis;

[0093] Take the head envelope centroid point obtained in step 15 as the origin, and take "head package X axis length", "head package Y axis length", and "head package Z axis length" in step 16 as length values, and make the head envelope X axis, Y axis, and Z axis; the angle between the head envelope X axis and the horizontal plane is β;

[0094] 18) According to the head envelope Z axis obtained in step 17, take the head envelope centroid point obtained in step 15 as the circle point to make a circle;

[0095] 19) Take the circle in step 18 as a reference with the head envelope X axis, Y axis, and Z axis in step 17, and use the affine command of CATIA software to make a complete ellipsoidal sphere;

[0096] 20) Take the ellipsoidal sphere in step 19 and divide it into upper and lower hemispheres with the plane formed by the head envelope X axis and Y axis in step 17, discard the lower hemisphere, and retain the upper hemisphere;

[0097] 21) The upper hemisphere in step 20) is divided into two half-curves by the plane formed by the X-axis and the Z-axis of the head envelope obtained in step 17), and the half-curve on the outside (negative direction of the Y-axis) is offset by 23 mm in the negative direction of the Y-axis, and a splicing curve is made between the unshifted curve and the curve offset by 23 mm, and the unshifted curve, the curve offset by 23 mm, and the splicing curve are fitted into an integral curve, that is, the parameterized head envelope is obtained;

[0098] 22) The process of steps 1) to 21) is made into an intelligent design template for automobile eye ellipse and head envelope and saved as a part file for subsequent calling by applying the "insert-knowledge engineering template-user features" command.

[0099] In this way, the above design process ingeniously uses some intermediate parameters as conversion, and uses the conversion and conversion between other parameters based on the spatial relationship of the geometric structure, saving the calculation steps. The selection of unique intermediate parameters and the use of VB computer language make the conversion process more simple and reliable. At the same time, the CATIA software is used to directly make the design process into a template, and the conversion relationship between the fixed input parameters, the variable parameters and the intermediate parameters and the output parameters based on the geometric shape confirmation and the conversion relationship based on the design standard is fixed to the knowledge engineering template module of the CATIA software. After the conversion relationship is fixed, the designer can directly call the template in the subsequent design process, modify the variable parameters, directly obtain the output parameters, and use the software itself to display the intuitive structure of the output parameters, so as to facilitate the designer to adjust and select the parameters in the design process.

[0100] Further, in step 1), the design reference point data comes from the preliminary design scheme of the specific vehicle design project. Because in automobile design, AHP point, H point and SWC point are the three design reference points defined first, this paper does not discuss the positioning method of these three points, but only discusses how to make the driver's eye ellipse and head envelope after the three reference points are known. Therefore, the above three design reference points can be established by three coordinate method according to the preliminary design scheme of the specific project, or the original point data can be copied and pasted into the newly established part file.

[0101] Further, when assigning values to the variable parameters in step 2), any value within the value range is assigned. Because the assignment here provides values for the calculation of the conversion relationship between the variable parameters and the intermediate parameters, any value can be assigned.

[0102] Further, step B specifically includes the following steps:

[0103] 23) In CATIA software, switch to the car eye ellipse and head envelope intelligent design template part file in step 22 through the "insert-from selection instantiation" command on the toolbar, select the directory tree, and pair the AHP point, H point and SWC point to be designed with the AHP point, H point and SWC point in the template according to the window prompt, and end the call after confirming that there is no error;

[0104] 24) The application structure tree of the template is generated on the part file directory tree in step 23, and the left and right eye ellipses, the left and right eye ellipse center points and the head envelope are displayed in the 3D data window. Open the structure tree, modify the parameters "TL23", "A47", "human body percentile" and "clutch pedal state" to meet the needs of the new vehicle project, and then the left and right eye ellipses, the left and right eye ellipse center points and the head envelope are updated, that is, the corresponding eye ellipses, eye ellipse center points and head envelopes are synchronously displayed.

[0105] Therefore, when designing in this way, there is no need to check the table to see the formula, nor is there a need to repeatedly calculate according to the triangular geometric relationship, but only the model needs to be directly called and the value of the variable parameter needs to be changed. When any one of the four parameters "TL23", "A47", "human body percentile" and "clutch pedal state" needs to be changed to obtain the corresponding eye ellipse or head envelope, the parameter can be directly changed in the structure tree, and the directory tree is updated to obtain the required eye ellipse, eye ellipse center point and head envelope.

[0106] Therefore, the present application first sorts out the design input of the modular design template of the eye ellipse and the head envelope, and the modeling process in the middle is managed through parameters and geometric constraints. The calculations and some design rules involved need to be established through embedded calculation formulas and VB conditional statements to achieve the purpose of automatically updating the geometric model. Finally, the modeling process in the middle is packaged and encapsulated as a whole to form an intelligent design template of the eye ellipse and the head envelope. Subsequent devices of this feature can be designed by calling the template, and through the pre-established input conditions and input values, the entire feature can be automatically updated to form a product model that meets the requirements of engineering design. Compared with the prior art, the present application realizes parameterized design of the eye ellipse and the head envelope, so that repeated product modeling is not needed during product design, and only limited parameters need to be changed to obtain the corresponding results, greatly shortening the design time, and the application results can be automatically updated with the change of the input conditions, avoiding repeated labor.

[0107] In summary, the present application not only quickly and accurately obtains the eye ellipse and the head envelope by inputting a small number of parameters, but also supports automatic updating of the output results with the change of the input parameters, greatly improving the design efficiency. Therefore, the present application has the advantages of being able to simplify the calculation process, reduce errors caused by repeated calculations, and better improve the design efficiency and accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0108] Figure 1 This is a schematic diagram of the three design benchmarks that serve as fixed input parameters in this invention.

[0109] Figure 2 This is a schematic diagram of the output results of the present invention.

[0110] Figure 3 This refers to Clause 4.1 of the standard SAE J941 referenced in step 8).

[0111] Figure 4 This refers to clause 7.1 of standard SAE J 1052, which is referenced in step 14).

[0112] Figure 5 This refers to clause 6.1 of SAE J1052, which is cited in step 16).

[0113] Figure 6 This is a schematic diagram showing the spatial relationship between the parameters in this method.

[0114] Figure 7 From Figure 6 A schematic diagram showing the relationship between the rear-view direction display parameters W20 and the SgRP point.

[0115] Figure 8 This is a typical elliptical space model for the left and right eyes.

[0116] Figure 9 This is a schematic diagram of the driver's head position contour at points where the seat travel trajectory is greater than 133mm in Class A vehicles. Detailed Implementation

[0117] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0118] Figure 1 This is a schematic diagram of the three design benchmarks that serve as fixed input parameters in this invention. Figure 1 Point 1 is AHP, point 2 is H, and point 3 is SWC.

[0119] Figure 2 This is a schematic diagram of the output results of the present invention. Figure 2 In the figure, number 4 is the center point of the left eye ellipse, number 5 is the elliptical surface of the left eye, number 6 is the center point of the right eye ellipse, number 7 is the elliptical surface of the right eye, and number 8 is the head envelope surface.

[0120] Figure 8 This is a typical elliptical space model for the left and right eyes. Figure 8 In the diagram, label 9 represents the X-axis of the left eye ellipse, label 10 represents the Y-axis of the left eye ellipse, and label 11 represents the Z-axis of the left eye ellipse.

[0121] Figure 9 Figure 1 is a schematic diagram of a driver head position profile for a seat trajectory of a Class A vehicle greater than 133mm. Figure 9 In figure 1, reference numeral 12 represents the head envelope ellipsoid centroid point, reference numeral 13 represents the head envelope X axis, reference numeral 14 represents the head envelope Y axis, reference numeral 15 represents the head envelope Z axis, reference numeral 16 represents the upper hemisphere fixed surface, reference numeral 17 represents the bridging surface of the two surfaces, and reference numeral 18 represents the surface offset by 23mm in the Y direction.

[0122] The present application relates to the following professional terms:

[0123] Three-dimensional coordinate system: According to the provisions of SAE J 1100, the coordinate system in the 3D design of the automobile, which is divided into X axis, Y axis and Z axis, the X axis direction is from the front end to the rear end of the vehicle, the Y axis direction is from the left side to the right side of the vehicle, and the Z axis direction is from the lower part to the upper part of the vehicle.

[0124] Human body percentile: human body measurement language, a method for determining the distribution value of human body size. The percentile represents the percentage of the total number of statistical objects that have a certain human body size and are smaller than the size. Taking the 5th percentile and the human body height size as an example, it means that 5% of the people are equal to or less than the size.

[0125] HOS (heel point): Heel of Shoe, defined according to standard SAE J 1100, article 3.5.8, the lowest and last point of the lateral center plane of the shoe model, when it is correctly placed on the compressed floor, it defines the position of the driver AHP and the FRP point of the occupant. In design, the AHP point position coincides.

[0126] AHP point: Accelerator Heel Point, accelerator pedal heel point, defined according to standard SAE J 1100, article 3.5.1, which refers to the contact point between the sole surface of the shoe model of the H point device and the uncompressed accelerator pedal surface when the ankle angle is 87°, and the contact point between the heel and the floor surface, which is usually coincident with HOS.

[0127] BOF point: Ball of Foot, defined according to standard SAE J 1100, article 3.5.2, as a point 203mm away from the HOS point on the lateral center plane of the shoe model.

[0128] BOFRP point: Ball of Foot Reference Point, defined according to standard SAE J 1100, article 3.5.3, as a vehicle reference point consistent with the position of the driver's BOF point, which is only applicable to the position of the driver.

[0129] H point: H-Point, the intersection of the upper leg line and the torso line as defined in SAE J 1100, 3.4.5, or SAE J826. In vehicle design, H point coincides with SgRP point and can be used as a vehicle reference point.

[0130] SgRP point (R point): Seating Reference Point, the reference point defined at the beginning of the vehicle design process, as defined in SAE J 1100, 3.4.8. It is the most important point for the driver. It is used to locate some layout tools and is used to define many key dimensions, which are set as a reference by domestic and international standards and regulations. It coincides with the H point in design.

[0131] FDH point: Front Design H point, a point defined in SAE J 1100, referring to the H point when the sliding seat is slid to the front.

[0132] TL23: SAE J1100 defines the length from SgRP point to FDH point, also known as H point travel trajectory, or seat track travel, generally >133mm, <133mm, 0mm three range values. Generally, the driver's seat is adjustable forward and backward, and the TL23 value is generally greater than 133mm, and the second row seat is generally not adjustable.

[0133] Eye ellipse and eye ellipse center point: SAE J 941 specifies the specific method, mainly used for checking the driver's field of view when sitting in the car. See Figure 8 .

[0134] SWC point: Steering Wheel Center, the center point of the steering wheel, defined in SAE J 1100, 3.3.22, the front wheel is in the vertical forward position, and the angle between the steering column and the plane tangent to the steering wheel rim is a reference point for the vehicle.

[0135] H30: Seat height, as defined in SAE J 1100, it is usually the vertical distance from the SgRP point to the AHP point.

[0136] W20: SAE J 1100 defines the Y coordinate of the SgRP point.

[0137] H8: SAE J 1100 defines the Z coordinate of the AHP point.

[0138] L6: SAE J 1100 defines the horizontal distance between the BOFRP point and the steering wheel center.

[0139] L1: SAE J 1100 defines the X coordinate of the BOFRP point.

[0140] A47: The angle between the driver's shoe plane and the horizontal plane defined in SAE J 1100.

[0141] β: The reclining angle of the eye ellipse of the fixed seat (Z axis reclines backward from the vertical direction) as seen in the side view.

[0142] t: The type coefficient of the transmission system, 1 indicates that there is a clutch pedal, 0 indicates that there is no clutch pedal;

[0143] The three coordinate axes of the head envelope and the centroid of the head envelope ellipsoid: The head position profile is constructed by modifying a 3D ellipsoid, the size of the initial ellipsoid is defined by the length of the X, Y and Z axes, which depends on the required human percentile and TL23, the centroid of the initial ellipsoid is used to position the points of the complete head profile. See Figure 9 for understanding.

[0144] A modular design method for automobile eye ellipses and head envelopes, characterized in that it comprises the following steps:

[0145] Step A: Based on the secondary development function of CATIA software, a knowledge engineering template file (part file) capable of directly displaying the design target structure is established, and AHP point, H point and SWC point are taken as fixed input parameter information; "TL23", "A47", "human percentile" and "clutch pedal state" are taken as variable parameter information; "H30", "W20", "L6", "L1", "H8", "β", "t", "eye ellipse X axis length", "eye ellipse Y axis length", "eye ellipse Z axis length", "Xh", "Zh", "head package X axis length", "head package Y axis length" and "head package Z axis length" are taken as intermediate parameters; left and right eye ellipses, left and right eye ellipse center points and head envelope are taken as output parameter information, the corresponding relationship between the input parameter information, the intermediate parameter information and the output parameter information in the knowledge engineering template file is established and automatic conversion association is realized; an intelligent design template for automobile eye ellipses and head envelopes is obtained;

[0146] Step B: The intelligent design template for automobile eye ellipses and head envelopes established in step A is called in CATIA software, different variable parameter information is input according to the design needs, and the knowledge engineering template automatically runs and directly displays the calculated output parameters in the form of graphics.

[0147] Thus, the method utilizes the secondary development function of CATIA software, presets the corresponding relationship between the input parameters and the output parameters into the knowledge engineering template file, establishes the corresponding model, so that only the input parameter information to be adjusted needs to be input during design, and the corresponding automobile eye ellipse and head envelope graphics are automatically calculated and output by the model. The designer can quickly adjust the input parameters and instantly obtain the change of the automobile eye ellipse and head envelope graphics, and judge whether the design is reasonable. Specifically, in the scheme, the common input parameters required for automobile eye ellipse and head envelope design are selected, and then appropriate intermediate parameters are selected, so as to drive the corresponding geometric figure change by the input parameters and the intermediate parameters, and realize the automatic conversion correlation between the input parameters, the intermediate parameters and the output parameters. Thus, only the preset engineering template file needs to be called during design, and the calculation result of the corresponding automobile eye ellipse and head envelope image generated following the change of the input information can be realized by changing the input information of the variable parameters. Therefore, the method can simplify the calculation process, reduce repetitive labor, avoid human calculation error, improve design accuracy, and better improve design efficiency and accuracy.

[0148] During implementation, step A specifically includes the following steps:

[0149] 1) Open the CATIA software, establish a knowledge engineering template file (part file) capable of directly displaying the design target structure, establish a horizontal rectangular coordinate system in the template file, the coordinate system is a horizontal rectangular coordinate system, the direction of X coordinate is set along the length direction of the vehicle, the direction of Y coordinate is set along the width direction of the vehicle, and the direction of Z coordinate is set along the height direction of the vehicle; then establish design reference points as fixed input parameters in the coordinate system: AHP point, H point and SWC point;

[0150] 2) Establish the variable parameters to be input: “TL23”, “A47”, “human body percentile” and “clutch pedal state”, and assign values to the parameters to be input in step 2) according to the variable parameter value range;

[0151] Among them:

[0152] “TL23”: refers to the length from SgRP (seat reference point) to FDH (the most forward design H point), which is generally distinguished by the range, “TL23”>133mm, “TL23”<133mm or “TL23”=0mm (at this time, it is a fixed seat);

[0153] “A47”: refers to the angle between the driver's shoe plane and the horizontal plane defined in SAE J 1100, which is generally the angle between the driver's foot pedal and the horizontal plane when the driver steps on the accelerator pedal; the value range is 0-90°;

[0154] “Body Percentile”: anthropometric term used to determine body size distribution values, a body percentile represents the percentage of the total population of statistical subjects having a certain body size and less than that size; (take the 95th percentile, body height size as an example, which means that 95% of the people are equal to or less than this size) SAE J 941 and SAE J 1052 only define the 95th and 99th percentile bodies, i.e. the values here are 95 or 99;

[0155] “Clutch pedal status”: a multi-value parameter, divided into having a clutch pedal and not having a clutch pedal, represented as a coefficient t in the calculation formula, the percentage of vehicles containing clutch pedals in production vehicles determines the value of t, if 50% or more vehicles use clutch pedals, t takes 1, otherwise 0;

[0156] 3) Make BOFRP point: according to the AHP point assigned in the previous step and the defined A47 value, make the BOFRP point, the distance between the BOFRP point and the AHP point is 203 mm, and the included angle with the horizontal is A47; see attached Figure 1 ;

[0157] 4) Establish intermediate parameters “H30”, “W20”, “L6”, “L1” and “H8”;

[0158] According to the AHP point, H point, SWC point and BOFRP point determined in the previous steps, determine the values of the intermediate parameters according to the definition of the intermediate parameters;

[0159] W20: defined as the Y coordinate of the SgRP point in SAE J 1100; see attached Figure 7 ;

[0160] H30: seat height, specified in SAE J 1100, refers to the vertical distance from the SgRP point to the AHP point; see attached Figure 6 ;

[0161] H8: defined as the Z coordinate of the AHP point in SAE J 1100; see attached Figure 6 ;

[0162] L6: defined as the horizontal distance from the BOFRP point to the center point of the steering wheel in SAE J 1100;

[0163] L1: defined as the X coordinate of the BOFRP point in SAE J 1100; see attached Figure 6 ;

[0164] 5) Establish intermediate parameter “β”;

[0165] According to the provisions of SAE J 941 4.2, the X axis of the driver's eye ellipse of a Class A vehicle has a forward inclination angle β relative to the horizontal plane, equation 1: β = 12 deg;

[0166] According to the provisions of SAE J1052 4.1, the head envelope of the driver of the A-class vehicle has a forward inclination angle β, the value of which is related to TL23; if TL23 is not 0, the inclination angle is 12 deg; if TL23 is 0, there is no inclination angle;

[0167] The rule method of the CATIA knowledge engineering module is applied to associate TL23 in the foregoing step with β, and under the condition that TL23 is not 0, β = 12 deg;

[0168] 6) An intermediate parameter “t” is established; and the rule method of the knowledge engineering module is applied to establish the corresponding relationship between the value of t and the “clutch pedal state” parameter in the foregoing step by using VB language; if 50% or more of the vehicles use the clutch pedal, t takes 1, otherwise t takes 0;

[0169] 7) The parameterized eye ellipse center point is made:

[0170] Reference is made to equations 2, 3, 4, 5 (from SAE J 941 4.3):

[0171] Xc = L1 + 664 + 0.587 (L6) - 0.176 (H30) - 12.5t (2)

[0172] Ycl = W20 - 32.5 (3)

[0173] Ycr = W20 + 32.5 (4)

[0174] Zc = H8 + 638 + H30 (5);

[0175] Wherein the three coordinates of the left eye ellipse center point are Xc, Ycl, Zc (equation 2, equation 3, equation 5), and the three coordinates of the right eye ellipse center point are Xc, Ycr, Zc (equation 2, equation 4, equation 5); the values of the eye ellipse center point coordinates are obtained by substituting the values obtained in the foregoing step into the equations;

[0176] 8) Intermediate parameters “eye ellipse X-axis length”, “eye ellipse Y-axis length” and “eye ellipse Z-axis length” are established;

[0177] According to the provisions of item 4.1 in the standard SAE J941 (see Figure 3 ), the rule method of the knowledge engineering module is applied to edit the eye ellipse axis length selection rule by using VB language, and the established “TL23”, “human body percentile” are associated with the three parameters of “eye ellipse X-axis length”, “eye ellipse Y-axis length” and “eye ellipse Z-axis length”, so that the three parameters of “eye ellipse X-axis length”, “eye ellipse Y-axis length” and “eye ellipse Z-axis length” have corresponding values according to “TL23” and “human body percentile”;

[0178] 9) Make the eye ellipse three coordinate axes;

[0179] Take the left eye ellipse center point obtained in step 7 as the origin, and take the "eye ellipse X axis length", "eye ellipse Y axis length", and "eye ellipse Z axis length" three parameters in step 8 to make the left eye ellipse X axis, Y axis, and Z axis, wherein the included angle between the X axis and the horizontal plane is β;

[0180] 10) According to the length of the eye ellipse Z axis in step 9), make a spherical surface with the left eye ellipse center point as the center and name it spherical surface 1;

[0181] 11) According to the spherical surface 1 in step 10), take the left eye ellipse center point as the origin, take the three coordinate axes (X axis, Y axis, Z axis) of the eye ellipse in step 9), and use the affine command of CATIA software to make the left eye ellipse surface;

[0182] 12) In step (11), the left eye ellipse surface is translated from the left eye ellipse center point to the right eye ellipse center point by point-to-point translation, and the right eye ellipse surface is obtained;

[0183] 13) Make the eye ellipse centroid point: the eye ellipse centroid point is the midpoint of the left and right eye ellipse center points; according to the left and right eye ellipse center points obtained in step 8, make the centroid point between them; this point is the reference point of the centroid point of the head envelope ellipsoid;

[0184] 14) Establish intermediate parameters: "Xh" and "Zh";

[0185] According to the provisions of SAE J 1052 7.1 (see Figure 4 ), apply the rule method of the knowledge engineering module, edit the head envelope centroid point offset rule with VB language, and assign the corresponding values in the table under different ranges of TL23 to "Xh" and "Zh";

[0186] 15) Take the eye ellipse centroid point in step 14) as the reference point, and make the head envelope ellipsoid centroid point according to the three coordinate reference point method, wherein the X value of the point is "Xh", the Y value is 0, and the Z value is "Zh";

[0187] 16) Establish intermediate parameters: "head package X axis length", "head package Y axis length", and "head package Z axis length";

[0188] According to SAE J1052 6.1 (see Figure 5According to the provisions of the application knowledge engineering module, the rule method is adopted, the head envelope axis length rule is edited by VB language, the "TL23", "human body percentile" and "head package X axis length", "head package Y axis length", "head package Z axis length" are associated, so that the "head package X axis length", "head package Y axis length", "head package Z axis length" have corresponding values according to "TL23" and "human body percentile";

[0189] 17) Make head envelope X axis, Y axis, Z axis;

[0190] The head envelope X axis, Y axis, Z axis are made with the head envelope centroid point obtained in step 15 as the origin and the "head package X axis length", "head package Y axis length" and "head package Z axis length" in step 16 as length values, wherein the angle between the head envelope X axis and the horizontal plane is β;

[0191] 18) According to the head envelope Z axis obtained in step 17), a circle is made with the head envelope centroid point obtained in step 15 as the center;

[0192] 19) The circle in step 18) is made into a complete ellipsoidal body with the head envelope X axis, Y axis, Z axis in step 17) as reference by using the affine command of CATIA software;

[0193] 20) The ellipsoidal body in step 19) is divided into upper and lower hemispheres by the plane formed by the head envelope X axis and Y axis obtained in step 17), the lower hemisphere is discarded and the upper hemisphere is retained;

[0194] 21) The upper hemisphere in step 20) is divided into left and right half-curves by the plane formed by the head envelope X axis and Z axis obtained in step 17), the half-curve on the outside (Y axis negative direction) is offset by 23mm in the Y axis negative direction, the unshifted curve and the offset curve are spliced in the middle to form a whole curve, that is, the parameterized head envelope is obtained;

[0195] 22) The process of steps 1) to 21) is made into an intelligent design template for automobile eye ellipse and head envelope and saved as a part file by applying the "insert-knowledge engineering template-user characteristics" command, which can be called later.

[0196] Thus, the above design process ingeniously utilizes some intermediate parameters as conversion, utilizes conversion between them and other parameters based on geometric spatial relationship, saves calculation steps. The selection of unique intermediate parameters makes the conversion process more simple and reliable. At the same time, the CATIA software is directly used to make the design process into a template, and the conversion relationship between the fixed input parameters, variable parameters and intermediate parameters and output parameters based on geometric shape confirmation and the conversion relationship based on design standard regulation is solidified into the knowledge engineering template module of the CATIA software. After the conversion relationship is solidified, the designer can directly call the template in the subsequent design process, directly obtain the output parameters by modifying the variable parameters, and obtain the intuitive structure display of the output parameters by using the software display function, so as to facilitate the designer to adjust and select the parameters in the design process.

[0197] In implementation, in step 1), the design reference point data comes from the preliminary design scheme of a specific vehicle design project. Because in automobile design, the AHP point, the H point and the SWC point are the three points defined first, this paper does not discuss the positioning method of the three points, but only discusses how to make the driver's eye ellipse and head envelope after the three reference points are known. Therefore, the above three design reference points can be established by three coordinate method according to the preliminary design scheme of the specific project, or the original point data can be copied and pasted into the newly established part file.

[0198] In implementation, when the variable parameters in step 2) are assigned values, any value in the value range is assigned. Because the assignment here is to provide values for subsequent calculation of the conversion relationship between the variable parameters and the intermediate parameters, any value can be taken.

[0199] In implementation, step B specifically includes the following steps:

[0200] 23) In the CATIA software, switch to the automobile eye ellipse and head envelope intelligent design template part file in step 22) through the "insert - instantiation from selection" command on the tool bar, point the directory tree, and according to the window prompt, pair the AHP point, H point and SWC point to be designed with the AHP point, H point and SWC point in the template, and end the calling after confirming that there is no error;

[0201] 24) The application structure tree of the template is generated on the part file directory tree in step 23), and the left and right eye ellipses, the left and right eye ellipse center points and the head envelope are displayed in the 3D data window. Open the structure tree, modify the parameters "TL23", "A47", "human body percentile" and "clutch pedal state" to meet the needs of the new vehicle project, then the left and right eye ellipses, the left and right eye ellipse center points and the head envelope are updated, and the corresponding eye ellipses, eye ellipse center points and head envelope are displayed synchronously.

[0202] Therefore, when the design is performed, no table lookup or repeated calculation according to the triangle geometry is needed, and only the model is directly called and the value of the variable parameter is changed, when any one of the four parameters of "TL23", "A47", "human body percentile" and "state of clutch pedal" is changed to obtain the corresponding eye ellipse or head envelope, the parameter is directly changed in the structure tree, the directory tree is updated, and the required eye ellipse, eye ellipse center point and head envelope are obtained.

[0203] Therefore, the application firstly arranges the design input of the modular design template of the eye ellipse and the head envelope, the modeling process in the middle is managed through parameters and geometric constraints, the calculation and some design rules involved need to be embedded with calculation formulas and established with VB conditional statements to achieve the purpose of automatically updating the geometric model, finally the modeling process in the middle is packaged and encapsulated as a whole to form the modular design template of the eye ellipse and the head envelope, and all subsequent devices of the feature can be designed by calling the template, the input value is designed by predefining the input condition, the whole feature can be automatically updated, and the product model meeting the engineering design requirement is formed. Compared with the prior art, the application realizes the parametric design of the eye ellipse and the head envelope, the product modeling is not needed to be repeated in the product design process, only limited parameters are changed to obtain the corresponding result, the design time is greatly shortened, the application result can be automatically updated with the change of the input condition, and the repeated labor is avoided.

Claims

1. A modular design method for automotive eye ellipse and head envelope, characterized in that, The method comprises the following steps: Step A: based on the secondary development function of CATIA software, a knowledge engineering template file capable of visually displaying a design target structure is established, and AHP point, H point and SWC point are taken as fixed input parameter information; "TL23", "A47", "human body percentile" and "clutch pedal state" are taken as variable parameter information; "H30", "W20", "L6", "L1", "H8", "β", "t", "eye ellipse X axis length", "eye ellipse Y axis length", "eye ellipse Z axis length", "Xh", "Zh", "head envelope X axis length", "head envelope Y axis length" and "head envelope Z axis length" are taken as intermediate parameters; left and right eye ellipses, left and right eye ellipse center points and head envelope are taken as output parameter information, and the corresponding relationship between the input parameter information, the intermediate parameter information and the output parameter information is established in the knowledge engineering template file, and automatic conversion association is realized; An intelligent design template of automobile eye ellipses and head envelopes is obtained; Step B: the intelligent design template of automobile eye ellipses and head envelopes established in step A is called in CATIA software, different variable parameter information is input according to design needs, the knowledge engineering template automatically runs and visually displays the calculated output parameters in the form of graphics; Step A specifically comprises the following steps: 1) opening CATIA software, establishing a knowledge engineering template file capable of visually displaying a design target structure, establishing a horizontal rectangular coordinate system in the template file, the coordinate system is a horizontal rectangular coordinate system, the direction of the X coordinate is arranged along the length direction of the vehicle, the direction of the Y coordinate is arranged along the width direction of the vehicle, and the direction of the Z coordinate is arranged along the height direction of the vehicle; then establishing design reference points AHP point, H point and SWC point in the coordinate system; 2) establishing variable parameters to be input: "TL23", "A47", "human body percentile" and "clutch pedal state", and assigning values to the parameters to be input in step 2) according to the variable parameter value range; Wherein: "TL23": refers to the length from SgRP to FDH, and is divided into ranges, "TL23">133mm, "TL23"<133mm or "TL23"=0mm; "A47": refers to the angle between the driver's shoe plane and the horizontal plane defined in SAE J 1100, that is, the angle between the driver's foot pedal and the horizontal plane when the driver steps on the accelerator pedal; the value range is 0-90°; "Human body percentile": a human body measurement term used to determine human body size distribution values, human body percentile represents the percentage of people with a certain human body size and smaller than the size in the total number of statistical objects; SAE J 941 and SAE J 1052 only define 95 and 99 percentile human bodies, that is, the value here is 95 or 99; "Clutch pedal state": a multi-value parameter, divided into having a clutch pedal and not having a clutch pedal, represented by coefficient t in the calculation formula, the percentage of vehicles containing a clutch pedal in production vehicles determines the value of t, if 50% or more vehicles use a clutch pedal, t is 1, otherwise, t is 0; 3) Make BOFRP point: According to the AHP point assigned in the previous step and the A47 value defined, make the BOFRP point, the distance between the BOFRP point and the AHP point is 203 mm, and the included angle with the horizontal is A47; 4) Establish intermediate parameters "H30", "W20", "L6", "L1" and "H8"; According to the AHP point, H point, SWC point and BOFRP point determined in the previous step, and according to the definition of the intermediate parameters, the values of the intermediate parameters are determined; W20: SAE J 1100 defines SgRP point Y coordinate; H30: Seat height, SAE J 1100 specifies the size, which refers to the vertical distance between SgRP point and AHP point; H8: SAE J 1100 defines AHP point Z coordinate; L6: SAE J 1100 defines the horizontal distance between BOFRP point and steering wheel center point; L1: SAE J 1100 defines BOFRP point X coordinate; 5) Establish intermediate parameter "β"; According to SAE J941 4.2, the X axis of the driver's eye ellipse of a class A vehicle has a forward inclination angle β relative to the horizontal plane, equation 1: β = 12 deg; According to SAE J1052 4.1, the driver's head envelope of a class A vehicle has a forward inclination angle β, which is related to TL23; if TL23 is not 0, the inclination angle is 12 deg; if TL23 is 0, there is no inclination angle; According to the rule method of CATIA knowledge engineering module, associate TL23 with β in the previous step, and if TL23 is not 0, β = 12 deg; 6) Establish intermediate parameter "t"; and apply the rule method of the knowledge engineering module to establish the corresponding relationship between the value of t and the "clutch pedal state" parameter in the previous step, if 50% or more of the vehicles use the clutch pedal, t takes 1, otherwise t takes 0; 7) Make the parameterized eye ellipse center point: Referring to equations 2, 3, 4 and 5: Xc = L1 + 664 + 0.587 (L6) - 0.176 (H30) - 12.5t (2) Ycl = W20 - 32.5 (3) Ycr = W20 + 32.5 (4) Zc = H8 + 638 + H30 (5); Where the three coordinates of the left eye ellipse center point are Xc, Ycl and Zc, which are the values of equation 2, equation 3 and equation 5, and the three coordinates of the right eye ellipse center point are Xc, Ycr and Zc, which are the values of equation 2, equation 4 and equation 5, which are calculated by substituting the values obtained in the previous step into the equations, to obtain the coordinate values of the eye ellipse center point; 8) Establish intermediate parameters: "eye ellipse X axis length", "eye ellipse Y axis length" and "eye ellipse Z axis length"; According to the provisions of SAE J941 4.1 Table 1, the rule method of knowledge engineering module is applied, the VB language is used to edit the eye ellipse axis length selection rule, the established "TL23", "human body percentile" and "eye ellipse X axis length", "eye ellipse Y axis length" and "eye ellipse Z axis length" are associated, so that the "eye ellipse X axis length", "eye ellipse Y axis length" and "eye ellipse Z axis length" have corresponding values according to "TL23" and "human body percentile"; 9) Make eye ellipse three coordinate axes; With the left eye ellipse center point obtained in step 7 as the origin, the "eye ellipse X axis length", "eye ellipse Y axis length" and "eye ellipse Z axis length" in step 8 are used to make the left eye ellipse X axis, Y axis and Z axis, wherein the included angle between the X axis and the horizontal plane is β; 10) According to the length of the eye ellipse Z axis in step 9), a spherical surface is made with the left eye ellipse center point as the center and is named as spherical surface 1; 11) According to the spherical surface 1 in step 10), the left eye ellipse surface is made with the left eye ellipse center point as the origin, the eye ellipse three coordinate axes in step 9) and the affine command of CATIA software; 12) The left eye ellipse surface in step (11) is translated from the left eye ellipse center point to the right eye ellipse center point in a point-to-point translation manner to obtain the right eye ellipse surface; 13) Make eye ellipse centroid point: the eye ellipse centroid point is the midpoint of the left and right eye ellipse center points; According to the left and right eye ellipse center points obtained in step 8, the centroid point between the two is made; The point is the reference point of the centroid point of the head envelope ellipsoid; 14) Establish intermediate parameters: "Xh", "Zh"; According to the provisions of SAE J1052 7.1 Table 4, the rule method of knowledge engineering module is applied, the VB language is used to edit the head envelope centroid point offset rule, and the corresponding values of TL23 in different ranges in the table are assigned to "Xh" and "Zh"; 15) Take the eye ellipse centroid point in step 14) as the reference point, and make the head envelope ellipsoid centroid point by the three coordinate reference point method, the X value of the point is "Xh", the Y value is 0, and the Z value is "Zh"; 16) Establish intermediate parameters: "head package X axis length", "head package Y axis length" and "head package Z axis length"; According to the provisions of SAE J1052 6.1 Table 1, the rule method of knowledge engineering module is applied, the VB language is used to edit the head envelope axis length rule, and the "TL23", "human body percentile" established in step 2 are associated with "head package X axis length", "head package Y axis length" and "head package Z axis length", so that the "head package X axis length", "head package Y axis length" and "head package Z axis length" have corresponding values according to "TL23" and "human body percentile"; 17) Make head envelope X axis, Y axis and Z axis; Taking the head envelope centroid point obtained in step 15 as the origin and the "head package X axis length", "head package Y axis length" and "head package Z axis length" three parameters in step 16 as length values, the X axis, Y axis and Z axis of the head envelope are made; wherein the angle between the X axis of the head envelope and the horizontal plane is β; 18) According to the head envelope Z axis obtained in step 17), a circle is made with the head envelope centroid point obtained in step 15 as the circle point; 19) The circle in step 18) is taken as a reference with the head envelope X axis, Y axis and Z axis in step 17) using the affine command of CATIA software to make a complete ellipsoidal sphere; 20) The ellipsoidal sphere in step 19) is divided into upper and lower hemispheres with the plane formed by the head envelope X axis and Y axis in step 17), the lower hemisphere is discarded and the upper hemisphere is retained; 21) The upper hemisphere in step 20) is divided into left and right hemisurfaces with the plane formed by the head envelope X axis and Z axis in step 17), the outer half of the surface is offset by 23mm in the negative direction of the Y axis, a splicing surface is made between the unshifted surface and the outer surface shifted by 23mm, and the unshifted surface, the outer surface shifted by 23mm and the splicing surface are fitted into an integral surface, that is, the parameterized head envelope is obtained; 22) The process of steps 1) to 21) is made into an automobile eye ellipse and head envelope intelligent design template and saved as a part file for subsequent calling by applying the "insert-knowledge engineering template-user features" command.

2. The modular design method of the eye-ellipse and head envelope of an automobile as claimed in claim 1, wherein, In step 1), the design reference point data comes from the preliminary design scheme of the specific vehicle design project.

3. The modular design method of the eye-ellipse and head envelope of an automobile as claimed in claim 1, wherein, When assigning values to the variable parameters in step 2), any value within the value range is assigned.

4. The modular design method of the eye-ellipse and head envelope of an automobile as claimed in claim 1, wherein, Step B specifically includes the following steps: 23) In CATIA software, switch to the automobile eye ellipse and head envelope intelligent design template part file in step 22) through the "insert-from selected instantiation" command on the tool bar, point to the directory tree, and according to the window prompt, pair the AHP point, H point and SWC point to be designed with the AHP point, H point and SWC point in the template, and end the calling after confirming that there is no error; 24) The application structure tree of the template is generated on the part file directory tree in step 23), and the left and right eye ellipses, the left and right eye ellipse center points and the head envelope are displayed in the 3D data window. Open the structure tree, modify the parameters "TL23", "A47", "human body percentile" and "clutch pedal state" to meet the needs of the new vehicle project, then the left and right eye ellipses, the left and right eye ellipse center points and the head envelope are updated, and the corresponding eye ellipses, eye ellipse center points and head envelope are displayed simultaneously.

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