Torsional stiffness determination, frame design method and device, frame and working machine

Abstract

The application provides a torsional stiffness determination method, a frame design method and device, a frame and a working machine, the torsional stiffness determination method comprising: restraining a first constraint point in a finite element model of the working machine in degrees of freedom in a first direction and a third direction, restraining a second constraint point in the finite element model in degrees of freedom in the first direction, a second direction and the third direction, restraining a third constraint point in the finite element model in degrees of freedom in the third direction, respectively applying forces with the same size and opposite directions to a first loading point and a second loading point in the finite element model, and obtaining a deformed finite element model; obtaining a displacement map of the deformed finite element model, and obtaining the torsional stiffness of the frame of the working machine based on the displacement map. The torsional stiffness determination method, the frame design method and device, the frame and the working machine provided by the application can avoid problems such as over-constraint and structural stress exceeding yield, and can more accurately and efficiently determine the torsional stiffness of the frame of the working machine.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, and in particular to a method and device for determining torsional stiffness, designing a chassis, a chassis, and operating machinery. Background Technology

[0002] The chassis is the base of a car, generally composed of two longitudinal beams and multiple transverse beams. The torsional stiffness of the chassis determines the vehicle's ability to resist deformation when encountering twisting surfaces or sharp cornering, and is positively correlated with the structural strength of the chassis. Quickly and accurately determining the torsional stiffness of the chassis can provide a basis for vehicle control under complex operating conditions. It also allows for rapid verification of chassis design schemes during the chassis design process, thereby shortening the design cycle, reducing the number of tests, lowering R&D costs, and improving product competitiveness.

[0003] Existing technologies can determine the torsional stiffness of a vehicle frame based on finite element analysis by constraining all degrees of freedom of the suspension frame hardpoint in the finite element model of the frame and applying opposite forced displacements on both sides of the suspension frame hardpoint. However, existing methods for determining torsional stiffness suffer from problems such as over-constraint of the finite element model of the frame and over-yielding of structural stress, resulting in low accuracy of the torsional stiffness of the frame determined by existing methods. Summary of the Invention

[0004] This invention provides a method and apparatus for determining torsional stiffness and designing a vehicle frame, as well as a vehicle frame and working machinery, to solve the defect of low accuracy in determining the torsional stiffness of the vehicle frame in the prior art, and to achieve more accurate determination of the torsional stiffness of the vehicle frame.

[0005] This invention provides a method for determining torsional stiffness, comprising:

[0006] Construct a finite element model of the operating machinery;

[0007] The first constraint point in the finite element model is constrained in its degrees of freedom in the first and third directions; the second constraint point in the finite element model is constrained in its degrees of freedom in the first, second, and third directions; the third constraint point in the finite element model is constrained in its degrees of freedom in the third direction; forces of the same magnitude but opposite directions are applied to the first and second loading points in the finite element model to obtain the deformed finite element model; wherein, the first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; the third constraint point is located at the central axis of the crossbeam in the finite element model; the direction of the force applied at the first loading point is either the third direction or the opposite direction of the third direction;

[0008] Obtain the displacement diagram of the deformed finite element model, and based on the displacement diagram, obtain the torsional stiffness of the frame of the operating machinery.

[0009] According to the torsional stiffness determination method provided by the present invention, the step of obtaining the torsional stiffness of the frame of the operating machinery based on the displacement diagram specifically includes:

[0010] Based on the displacement diagram, the torsional angle of the frame of the finite element model is obtained according to the arcsine formula;

[0011] The torsional stiffness of the vehicle frame is obtained based on the torsion angle.

[0012] According to a method for determining torsional stiffness provided by the present invention, the first direction is a direction parallel to the horizontal rearward direction of the machine body; the second direction is a direction perpendicular to the first direction and horizontally to the right; and the third direction is a direction perpendicular to the horizontal plane and upward.

[0013] According to a method for determining torsional stiffness provided by the present invention, the third constraint point is located on the central axis of the first beam in the finite element model, and the first beam is a beam located at the front of the finite element model.

[0014] According to the torsional stiffness determination method provided by the present invention, the third constraint point is located on the central axis of the second beam in the finite element model, and the second beam is a beam located at the rear of the finite element model.

[0015] According to the torsional stiffness determination method provided by the present invention, the number of the third constraint points is multiple.

[0016] The present invention also provides a chassis design method, comprising:

[0017] The torsional stiffness of the frame to be designed is obtained based on any of the torsional stiffness determination methods described above.

[0018] Based on the torsional stiffness of the frame to be designed, the structural strength of the frame to be designed is obtained;

[0019] Based on the torsional stiffness and structural strength of the chassis to be designed, a design scheme for the chassis to be designed is obtained.

[0020] The present invention also provides a vehicle frame, comprising: the vehicle frame being designed based on the vehicle frame design method described above.

[0021] The present invention provides a working machine, including: a frame as described above.

[0022] The present invention also provides a chassis design device, comprising:

[0023] The stiffness acquisition module is used to acquire the torsional stiffness of the frame to be designed based on any of the torsional stiffness determination methods described above.

[0024] The strength acquisition module is used to acquire the structural strength of the frame to be designed based on the torsional stiffness of the frame to be designed.

[0025] The chassis design module is used to obtain the design scheme of the chassis to be designed based on the torsional stiffness and structural strength of the chassis to be designed.

[0026] The present invention also provides a torsional stiffness determining device, comprising:

[0027] The model building module is used to build finite element models of the operating machinery;

[0028] A deformation loading module is used to constrain the degrees of freedom of a first constraint point in the finite element model in a first direction and a third direction, constrain the degrees of freedom of a second constraint point in the finite element model in the first direction, the second direction, and the third direction, and constrain the degree of freedom of a third constraint point in the finite element model in the third direction. Forces of equal magnitude and opposite directions are applied to the first loading point and the second loading point in the finite element model to obtain a deformed finite element model. The first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; the third constraint point is located at the central axis of the crossbeam in the finite element model; the direction of the force applied at the first loading point is either the third direction or the opposite direction of the third direction.

[0029] The stiffness determination module is used to obtain the displacement diagram of the deformed finite element model, and based on the displacement diagram, to obtain the torsional stiffness of the frame of the operating machinery.

[0030] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the torsional stiffness determination method as described above, and / or the frame design method as described above.

[0031] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the torsional stiffness determination method as described above, and / or the frame design method as described above.

[0032] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the torsional stiffness determination method as described above, and / or the frame design method as described above.

[0033] The present invention provides a method and apparatus for determining torsional stiffness, a frame design method and apparatus, a frame, and a working machine. By constructing a finite element model of the working machine, the methods constrain the degrees of freedom of a first constraint point located at the lower flange of the first longitudinal beam in the finite element model in the first and third directions; constrain the degrees of freedom of a second constraint point located at the lower flange of the second longitudinal beam in the finite element model in the first, second, and third directions; constrain the degrees of freedom of a third constraint point located at the central axis of the crossbeam in the finite element model in the third direction; and constrain the degrees of freedom of a first constraint point located at the lower flange of the first longitudinal beam in the finite element model and the third constraint point located at the central axis of the crossbeam in the finite element model in the third direction. In the finite element model, forces of the same magnitude but opposite direction are applied to the second loading point at the lower flange of the second longitudinal beam. The direction of the force applied at the first loading point is either the third direction or the opposite direction of the third direction. After obtaining the deformation finite element model and its displacement diagram, the torsional stiffness of the frame of the operating machinery is obtained based on the displacement diagram of the finite element model. This avoids problems such as over-constraint and structural stress over-yield in the finite element model of the operating machinery during the determination of torsional stiffness, reduces calculation errors, and allows for more accurate and efficient determination of the torsional stiffness of the frame of the operating machinery. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0035] Figure 1 This is a flowchart illustrating the torsional stiffness determination method provided by the present invention;

[0036] Figure 2 This is a schematic diagram of the finite element model of the frame of the operating machinery in the torsional stiffness determination method provided by the present invention;

[0037] Figure 3 This is a flowchart illustrating the chassis design method provided by the present invention;

[0038] Figure 4 This is a schematic diagram of the torsional stiffness determination device provided by the present invention;

[0039] Figure 5 This is a structural schematic diagram of the chassis design device provided by the present invention;

[0040] Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0042] In the description of the invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0043] It should be noted that in traditional methods for determining torsional stiffness, the constraints and loading on the finite element model of the chassis can include the following methods: 1. Constraining all degrees of freedom of the front suspension hardpoint in the finite element model of the chassis, and applying opposite forced displacements in the direction perpendicular to the horizontal plane on both sides of the rear suspension hardpoint; 2. Constraining all degrees of freedom of the rear suspension hardpoint in the finite element model of the chassis, and applying opposite forced displacements in the direction perpendicular to the horizontal plane on both sides of the front suspension hardpoint; 3. Constraining all degrees of freedom of the left hardpoint of the rear suspension and the right hardpoint of the front suspension, and applying opposite forced displacements in the direction perpendicular to the horizontal plane on the right hardpoint of the rear suspension and the left hardpoint of the front suspension; 4. Constraining all degrees of freedom of the right hardpoint of the rear suspension and the left hardpoint of the front suspension, and applying opposite forced displacements in the direction perpendicular to the horizontal plane on the left hardpoint of the rear suspension and the right hardpoint of the front suspension.

[0044] Typically, constraining all degrees of freedom of the suspension frame hardpoint in the finite element model of the chassis will result in overconstraint, leading to inaccurate determination of the chassis's torsional stiffness. Applying opposite forced displacements in the directions perpendicular to the horizontal plane on both sides of the suspension frame hardpoint will cause the chassis finite element model to exhibit over-yielding stress. In the case of over-yielding stress in the chassis finite element model, the determined torsional stiffness of the chassis is of no practical significance.

[0045] To address this issue, the present invention provides a method for determining torsional stiffness. Based on the torsional stiffness determination method provided by the present invention, it is possible to avoid over-constraint and structural stress over-yielding in the finite element model of the frame, thereby enabling a more accurate determination of the torsional stiffness of the frame.

[0046] Figure 1This is a flowchart illustrating the torsional stiffness determination method provided by the present invention. The following is in conjunction with... Figure 1 The method for determining the torsional stiffness of the present invention is described. For example... Figure 1 As shown, the method includes: Step 101, constructing a finite element model of the operating machinery.

[0047] Specifically, based on the characteristics of the operating machinery, a finite element model of the operating machinery can be constructed through steps such as problem definition, geometric model establishment, element selection, element characteristic definition and mesh generation, model checking and processing, and boundary condition definition.

[0048] Step 102: Constrain the degrees of freedom of the first constraint point in the finite element model in the first direction and the third direction; constrain the degrees of freedom of the second constraint point in the finite element model in the first direction, the second direction and the third direction; constrain the degrees of freedom of the third constraint point in the finite element model in the third direction; apply forces of the same magnitude but opposite directions to the first loading point and the second loading point in the finite element model to obtain the deformed finite element model; wherein, the first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; the third constraint point is located on the central axis of the crossbeam in the finite element model; the direction of the force applied at the first loading point is either the third direction or the opposite direction of the third direction.

[0049] Specifically, a rigid coupling can be established in a region of a predetermined area at the lower flange of the first longitudinal beam in the aforementioned finite element model. This rigid coupling at the lower flange of the first longitudinal beam in the aforementioned finite element model can be used as the first constraint point and the first loading point. Similarly, a rigid coupling can be established in a region of a predetermined area at the lower flange of the second longitudinal beam in the aforementioned finite element model. This rigid coupling at the lower flange of the second longitudinal beam in the aforementioned finite element model can be used as the second constraint point and the second loading point.

[0050] It should be noted that the first and second lower flanges of the longitudinal beam are located on opposite sides of the aforementioned finite element model and are symmetrically distributed along the central axis of the front axis of the finite element model. When the first lower flange of the longitudinal beam is located on the left side of the finite element model, the second lower flange of the longitudinal beam is located on the right side; conversely, when the first lower flange of the longitudinal beam is located on the right side, the second lower flange of the longitudinal beam is located on the left side. In this embodiment of the invention, the location of the first lower flange of the longitudinal beam on the left or right side of the finite element model is not specifically limited.

[0051] It should be noted that, in the embodiments of the present invention, the left side, right side, front and rear of the finite element model are relative to the direction of the fuselage moving horizontally forward parallel to the finite element model.

[0052] It should be noted that the first constraint point and the second constraint point correspond to the first loading point and the second loading point, respectively, the front axis and the rear axis of the finite element model. For example, if the first constraint point is located at the lower flange of the first longitudinal beam intersecting the centerline of the front axis of the finite element model, and the second constraint point is located at the lower flange of the second longitudinal beam intersecting the centerline of the front axis of the finite element model, then the second loading point is located at the lower flange of the first longitudinal beam intersecting the centerline of the rear axis of the finite element model, and the second loading point is located at the lower flange of the second longitudinal beam intersecting the center point of the rear axis of the finite element model; or, if the first constraint point is located at the lower flange of the first longitudinal beam intersecting the centerline of the rear axis of the finite element model, and the second constraint point is located at the lower flange of the second longitudinal beam intersecting the centerline of the rear axis of the finite element model, then the second loading point is located at the lower flange of the first longitudinal beam intersecting the centerline of the front axis of the finite element model, and the second loading point is located at the lower flange of the second longitudinal beam intersecting the center point of the front axis of the finite element model.

[0053] A rigid coupling can be established at the midpoint of the central axis of the beam in the above finite element model, taking a region of a preset area as the third constraint point; or one or more rigid couplings can be established at any position of the central axis of the beam in the above finite element model, taking a region of a preset area as the third constraint point respectively.

[0054] It should be noted that the aforementioned beam can be located at the front or rear of the finite element model. In this embodiment of the invention, there is no specific limitation on whether the beam is located at the front or rear of the finite element model.

[0055] It should be noted that the preset area can be 120*120mm. 2 .

[0056] After constructing the finite element model of the operating machinery, constraints and loads can be applied to the finite element model.

[0057] To avoid over-constraints in the finite element model, constraints can be imposed on the finite element model by only constraining the degrees of freedom of the first constraint point in the first direction and the third direction, constraining the degrees of freedom of the second constraint point in the first direction, the second direction and the third direction, and constraining the degrees of freedom of the third constraint point in the third direction.

[0058] To prevent the structural stress from exceeding the yield limit in the aforementioned finite element model, a third-direction force can be applied at the first loading point and a third-direction force in the opposite direction at the second loading point; alternatively, a third-direction force can be applied at the first loading point and a third-direction force at the second loading point, thus loading the finite element model. The magnitudes of the forces applied at the first and second loading points are equal.

[0059] It should be noted that the first direction, second direction, and third direction can be determined according to the actual situation. For example, the first direction can be a horizontal forward direction parallel to the direction of the working machinery's movement, the second direction can be a horizontal rightward direction perpendicular to the first direction, and the third direction can be a direction perpendicular to the horizontal plane and upward. In this embodiment of the invention, the first direction, second direction, and third direction are not specifically limited.

[0060] After constraining and loading the above finite element model, the finite element model undergoes deformation, and the deformed finite element model can be obtained.

[0061] Step 103: Obtain the displacement diagram of the deformed finite element model, and based on the displacement diagram, obtain the torsional stiffness of the frame of the operating machinery.

[0062] Specifically, based on finite element analysis, the displacement diagram of the finite element model after the above deformation can be obtained.

[0063] Based on the displacement diagram of the finite element model after deformation, the torsional stiffness of the frame of the operating machinery can be obtained through numerical calculation and other methods.

[0064] This invention constructs a finite element model of a work machinery, constrains the degrees of freedom of a first constraint point located at the lower flange of the first longitudinal beam in the finite element model in the first and third directions, constrains the degrees of freedom of a second constraint point located at the lower flange of the second longitudinal beam in the finite element model in the first, second, and third directions, and constrains the degrees of freedom of a third constraint point located at the central axis of the crossbeam in the finite element model in the third direction. Forces of the same magnitude but opposite directions are applied to a first loading point located at the lower flange of the first longitudinal beam and a second loading point located at the lower flange of the second longitudinal beam in the finite element model, respectively. The direction of the force applied at the first loading point is either the third direction or the opposite direction of the third direction. After obtaining the displacement diagram of the deformed finite element model, the torsional stiffness of the work machinery's frame is obtained based on the displacement diagram. This avoids problems such as over-constraint and structural stress over-yielding in the finite element model of the work machinery during the determination of torsional stiffness, reduces calculation errors, and allows for more accurate and efficient determination of the torsional stiffness of the work machinery's frame.

[0065] Based on the above embodiments, the first direction is a horizontal direction parallel to the machine body and moving backward; the second direction is a horizontal direction perpendicular to the first direction and moving to the right; and the third direction is a direction perpendicular to the horizontal plane and moving upward.

[0066] Figure 2 This is a schematic diagram of the finite element model of the frame of the operating machinery in the torsional stiffness determination method provided by this invention. Figure 2 As shown, the first direction is a horizontal direction parallel to the machine body and moving backward, the second direction can be a horizontal direction perpendicular to the first direction and moving to the right, and the third direction can be a horizontal direction perpendicular to the horizontal plane and moving upward.

[0067] Optionally, a spatial rectangular coordinate system can be established with the center of the finite element model as the origin, the x-axis as the direction horizontally backward parallel to the machine body, the y-axis as the direction horizontally to the right perpendicular to the first direction, and the z-axis as the direction vertically upward perpendicular to the horizontal plane.

[0068] When the first constraint point 201 is located at the lower flange of the first longitudinal beam intersecting the center line of the front axis of the finite element model, and the second constraint point 202 is located at the lower flange of the second longitudinal beam intersecting the center line of the front axis of the finite element model, the first loading point 204 is located at the lower flange of the first longitudinal beam intersecting the center line of the rear axis of the finite element model, and the second loading point 205 is located at the lower flange of the second longitudinal beam intersecting the center point of the rear axis of the finite element model.

[0069] It should be noted that the third constraint point 203 can be located on the central axis of the beam in the aforementioned finite element model. The beam can be located at the front of the upper finite element model or at the rear. The specific location of the beam is not specifically limited in this embodiment of the invention.

[0070] Accordingly, to avoid over-constraint in the finite element model, the constraints on the finite element model can be achieved by only constraining the degrees of freedom of the first constraint point 201 in the x-axis and z-axis directions, constraining the degrees of freedom of the second constraint point 202 in the x-axis, y-axis and z-axis directions, and constraining the degrees of freedom of the third constraint point 203 in the z-axis direction.

[0071] To prevent the structural stress from exceeding the yield limit in the aforementioned finite element model, a force in the z-axis direction can be applied at the first loading point 204 and a force in the opposite z-axis direction can be applied at the second loading point 205; alternatively, a force in the opposite z-axis direction can be applied at the first loading point 204 and a force in the z-axis direction can be applied at the second loading point 205, thus loading the finite element model. The magnitudes of the forces applied at the first loading point 204 and the second loading point 205 are equal.

[0072] In this embodiment of the invention, the first direction is parallel to the horizontal rearward direction of the machine body, the second direction is perpendicular to the first direction and horizontal to the right, and the third direction is perpendicular to the horizontal plane and upward. This can more accurately simulate actual working conditions and further improve the accuracy of determining the torsional stiffness of the machine frame.

[0073] Based on the above embodiments, the third constraint point 203 is located on the central axis of the first beam in the finite element model; the first beam is the beam located at the front of the finite element model.

[0074] Specifically, the beam located at the front of the finite element model can be designated as the first beam 206, and the beam located at the rear of the finite element model can be designated as the second beam 207. In this embodiment of the invention, the third constraint point 203 is located on the central axis of the first beam 206 in the finite element model.

[0075] Accordingly, a third-direction force can be applied at the third constraint point 203 located on the central axis of the first beam 206 in the above finite element model.

[0076] In this embodiment of the invention, the third constraint point is located on the central axis of the first crossbeam in the finite element model of the working machinery. The first crossbeam is located at the front of the finite element model, which can avoid over-constraint in the finite element model of the working machinery during the determination of torsional stiffness and reduce calculation errors.

[0077] Based on the above embodiments, the third constraint point 203 is located on the central axis of the second beam 207 in the finite element model; the second beam 207 is a beam located at the rear of the finite element model.

[0078] In this embodiment of the invention, the third constraint point 203 is located on the central axis of the second beam 207 in the above finite element model.

[0079] Accordingly, a third-direction force can be applied at the third constraint point 203 located on the central axis of the second beam 207 in the above finite element model.

[0080] It should be noted that, compared to the case where the third constraint point 203 is located on the central axis of the first crossbeam 206 in the aforementioned finite element model, the torsional strength of the frame is determined more accurately when the third constraint point 203 is located on the central axis of the second crossbeam 207 in the aforementioned finite element model.

[0081] In this embodiment of the invention, the third constraint point is located on the central axis of the second crossbeam in the finite element model of the working machinery. The second crossbeam is located at the rear of the finite element model, which can better avoid over-constraint in the finite element model of the working machinery during the determination of torsional stiffness, and can further reduce calculation errors.

[0082] Based on the content of the above embodiments, there are multiple third constraint points 203.

[0083] Optionally, if there are multiple third constraint points 203, multiple regions with preset areas can be selected on the central axis of the first beam 206 in the above finite element model to establish rigid coupling. The number of such rigid couplings can be the same as the number of third constraint points 203.

[0084] Optionally, if there are multiple third constraint points 203, multiple regions with preset areas can be selected on the central axis of the second beam 207 in the above finite element model to establish rigid couplings. The number of such rigid couplings can be the same as the number of third constraint points 203. Each rigid coupling can be...

[0085] Preferably, the distance between any two adjacent third constraint points 203 can be equal.

[0086] In this embodiment of the invention, there are multiple third constraint points, and each third constraint point is distributed along the central axis of the beam. This can better avoid over-constraint in the finite element model of the working machinery during the determination of torsional stiffness, and can further reduce calculation errors.

[0087] Based on the above embodiments, the torsional stiffness of the frame of the operating machinery is obtained based on the displacement diagram, specifically including: based on the displacement diagram, the torsional angle of the frame of the finite element model is obtained according to the arcsine formula.

[0088] It should be noted that in traditional methods for determining torsional stiffness, the torsional angle of the finite element model's frame can be obtained based on the arctangent formula and the displacement diagram of the deformed finite element model. However, due to the inherent limitations of the arctangent formula, the accuracy of the calculated torsional angle may be low when the actual value of the torsional angle is large.

[0089] To improve the accuracy of the torsional angle calculated from the displacement diagram of the deformed finite element model, the torsional angle of the frame of the above-mentioned finite element model is calculated according to the arcsine formula in this embodiment of the invention.

[0090] The formula for calculating the torsion angle of the frame of the above finite element model based on the arcsine formula is as follows:

[0091]

[0092] Where 'a' represents the torsional angle of the frame in the finite element model; 'a' represents the distance between the first and second loading points. 'f1' represents the displacement of the first loading point; 'f2' represents the displacement of the second loading point. The displacements f1 and f2 of the first and second loading points can be determined based on the displacement diagram of the deformed finite element model described above.

[0093] The torsional stiffness of the frame is obtained based on the torsion angle.

[0094] Specifically, after obtaining the torsional angle α of the chassis in the finite element model, the torsional stiffness of the chassis of the operating machinery can be obtained through numerical calculation based on the torsional angle α of the chassis in the finite element model. The specific calculation formula is as follows:

[0095]

[0096] Where K represents the torsional stiffness of the machine frame, in N.mm / deg; F represents the magnitude of the force applied at the first loading point and the second loading point.

[0097] This invention obtains the torsional angle of the finite element model frame by using the displacement diagram and arcsine formula of the finite element model after deformation of the working machinery. Based on the torsional angle, the torsional stiffness of the working machinery frame is obtained by numerical calculation. This avoids the problem of low accuracy in determining the torsional stiffness when the actual value of the torsional angle is large, and can further improve the accuracy of determining the torsional stiffness.

[0098] The following example illustrates the torsional stiffness determination method provided by the present invention, using the first longitudinal beam lower flange as the longitudinal beam lower flange located on the left side of the above finite element model and the second longitudinal beam lower flange as the longitudinal beam lower flange located on the right side of the above finite element model, with a third-direction force applied at the first loading point in the above finite element model and a third-direction force applied at the second loading point in the above finite element model.

[0099] The degrees of freedom of the first constraint point in the first direction and the third direction, the degrees of freedom of the second constraint point in the first direction, the degrees of freedom of the second direction and the third direction, and the degrees of freedom of the third constraint point in the third direction are constrained in the finite element model to achieve the constraint of the finite element model. A third-direction force is applied to the first loading point in the finite element model, and a force in the opposite direction of the third direction is applied to the second loading point in the finite element model. The magnitude of the force applied to the first loading point and the second loading point is 1000 N, and the distance between the first loading point and the second loading point is L = 856 mm.

[0100] After constraining and loading the above finite element model, the model undergoes deformation. Based on the finite element analysis method, the displacement diagram of the deformed finite element model can be obtained. Based on the displacement diagram of the deformed finite element model, the displacement of the first loading point f1 = 2.28 mm and the displacement of the second loading point f2 = 2.28 mm can be obtained.

[0101] Based on formula (1), the torsional angle α of the finite element model frame can be calculated as 0.305°. Based on formula (2), the torsional stiffness K of the frame of the working machinery can be calculated as 2806.557 N.mm / deg.

[0102] Figure 3 This is a flowchart illustrating the frame design method provided by the present invention. The following is in conjunction with... Figure 3 The vehicle frame design method of the present invention is described. For example... Figure 3 As shown, the method includes: step 301, obtaining the torsional stiffness of the frame to be designed based on the torsional stiffness determination method described above.

[0103] Specifically, the torsional stiffness of the vehicle frame to be designed can be determined based on the torsional stiffness determination method provided by this invention.

[0104] It should be noted that the specific steps for determining the torsional stiffness of the frame to be designed based on the torsional stiffness determination method provided by the present invention can be found in the above embodiments, and will not be repeated here.

[0105] Step 302: Obtain the structural strength of the frame to be designed based on the torsional stiffness of the frame to be designed.

[0106] Specifically, based on the torsional stiffness of the frame to be designed, the structural strength of the frame to be designed can be obtained through numerical calculations and other methods.

[0107] Step 303: Based on the torsional stiffness and structural strength of the frame to be designed, obtain the design scheme of the frame to be designed.

[0108] Specifically, based on the torsional stiffness and structural strength of the chassis to be designed, the chassis to be designed can be designed to obtain the design scheme of the chassis to be designed.

[0109] This invention provides a method for obtaining the torsional stiffness of a vehicle frame to be designed, then obtaining the structural front end of the frame based on the torsional stiffness, and finally obtaining a design scheme for the frame based on the torsional stiffness and structural strength. This method enables more efficient and accurate frame design, shortens the design cycle, reduces the number of tests, lowers R&D costs, and improves product competitiveness.

[0110] Based on the above embodiments, a vehicle frame is provided, which is designed based on the vehicle frame design method described above.

[0111] Specifically, the chassis designed based on the chassis design method provided by this invention is more efficient and accurate in the chassis design process, with a shorter design cycle, fewer tests, and less R&D investment.

[0112] It should be noted that the specific steps for designing a vehicle frame based on the frame design method provided by this invention can be found in the above embodiments, and will not be repeated here.

[0113] The chassis in this embodiment of the invention is designed based on the chassis design method provided by the invention. It can obtain the design scheme of the chassis based on the torsional stiffness and structural strength of the chassis to be designed, and can perform chassis design more efficiently and accurately, shorten the design cycle, reduce the number of tests, reduce R&D costs, and improve product competitiveness.

[0114] Based on the above embodiments, a working machine includes: a frame as described above.

[0115] Specifically, the operating machinery includes a frame designed based on the frame design method provided by this invention, which is more efficient and accurate in the frame design process, with a shorter design cycle, fewer tests, and less R&D investment.

[0116] It should be noted that the operating machinery in the embodiments of the present invention can be various types of vehicles, such as small cars, medium-sized buses and heavy trucks; the operating machinery in the embodiments of the present invention can also be various types of engineering vehicles, such as concrete pump trucks and mixer trucks.

[0117] The chassis of the working machinery in the embodiments of the present invention is designed based on the chassis design method provided by the present invention. It can obtain the design scheme of the chassis based on the torsional stiffness and structural strength of the chassis to be designed, and can carry out chassis design more efficiently and accurately, shorten the design cycle, reduce the number of tests, reduce R&D costs, and improve product competitiveness.

[0118] Figure 4 This is a structural schematic diagram of the chassis design device provided by the present invention. The following is in conjunction with… Figure 4 The frame design apparatus provided by this invention will be described below, and the frame design apparatus described below can be referred to in correspondence with the frame design method provided by this invention described above. For example... Figure 4 As shown, the device includes: a stiffness acquisition module 401, a strength acquisition module 402, and a frame design module 403.

[0119] The stiffness acquisition module 401 is used to acquire the torsional stiffness of the frame to be designed based on the torsional stiffness determination method described above.

[0120] The strength acquisition module 402 is used to acquire the structural strength of the frame to be designed based on the torsional stiffness of the frame to be designed.

[0121] The frame design module 403 is used to obtain the design scheme of the frame to be designed based on the torsional stiffness and structural strength of the frame to be designed.

[0122] Specifically, the stiffness acquisition module 401, the strength acquisition module 402, and the frame design module 403 are electrically connected.

[0123] The stiffness acquisition module 401 can be used to determine the torsional stiffness of the frame to be designed based on the torsional stiffness determination method provided by the present invention.

[0124] It should be noted that the specific steps for determining the torsional stiffness of the frame to be designed based on the torsional stiffness determination method provided by the present invention can be found in the above embodiments, and will not be repeated here.

[0125] The strength acquisition module 402 can be used to obtain the structural strength of the frame to be designed through numerical calculation and other methods based on the torsional stiffness of the frame to be designed.

[0126] The frame design module 403 can be used to design the frame to be designed based on the torsional stiffness and structural strength of the frame to be designed, and obtain the design scheme of the frame to be designed.

[0127] This invention provides a method for obtaining the torsional stiffness of a vehicle frame to be designed, then obtaining the structural front end of the frame based on the torsional stiffness, and finally obtaining a design scheme for the frame based on the torsional stiffness and structural strength. This method enables more efficient and accurate frame design, shortens the design cycle, reduces the number of tests, lowers R&D costs, and improves product competitiveness.

[0128] Figure 5 This is a structural schematic diagram of the torsional stiffness determining device provided by the present invention. The following is in conjunction with... Figure 5 The torsional stiffness determination device provided by this invention will be described below. The torsional stiffness determination device described below can be referred to in correspondence with the torsional stiffness determination method provided by this invention described above. For example... Figure 5 As shown, the device includes: a model building module 501, a deformation loading module 502, and a stiffness determination module 503.

[0129] Model building module 501 is used to build finite element models of the operating machinery.

[0130] The deformation loading module 502 is used to constrain the degrees of freedom of the first constraint point in the first direction and the third direction in the finite element model, constrain the degrees of freedom of the second constraint point in the first direction, the second direction and the third direction in the finite element model, and constrain the degrees of freedom of the third constraint point in the third direction in the finite element model. Forces of the same magnitude but opposite directions are applied to the first loading point and the second loading point in the finite element model to obtain the deformed finite element model. The first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; the third constraint point is located at the central axis of the crossbeam in the finite element model; the direction of the force applied at the first loading point is either the third direction or the opposite direction to the third direction.

[0131] The stiffness determination module 503 is used to obtain the displacement map of the finite element model after deformation, and based on the displacement map, to obtain the torsional stiffness of the frame of the operating machinery.

[0132] Specifically, the model building module 501, the deformation loading module 502, and the stiffness determination module 503 are electrically connected.

[0133] The model building module 501 can be used to construct a finite element model of the operating machinery based on its characteristics, through steps such as problem definition, geometric model establishment, element selection, element characteristic definition and mesh generation, model checking and processing, and boundary condition definition.

[0134] The deformation loading module 502 can be used to avoid over-constraint in the finite element model. It can constrain the finite element model by only constraining the degrees of freedom in the first direction and third direction of the first constraint point, the degrees of freedom in the first direction, second direction, and third direction of the second constraint point, and the degrees of freedom in the third direction of the third constraint point. To avoid structural stress over-yielding in the finite element model, a third-direction force can be applied to the first loading point and a force in the opposite direction of the third direction can be applied to the second loading point; alternatively, a force in the opposite direction of the third direction can be applied to the first loading point and a third-direction force can be applied to the second loading point. The magnitudes of the forces applied to the first and second loading points are the same. After constraining and loading the finite element model, it deforms, yielding a deformed finite element model.

[0135] The stiffness determination module 503 can be used for finite element analysis to obtain the displacement diagram of the finite element model after deformation. Based on the displacement diagram of the finite element model after deformation, the torsional stiffness of the frame of the operating machinery can be obtained through numerical calculations and other methods.

[0136] Optionally, the stiffness determination module 503 can be specifically used to obtain the torsional angle of the frame of the finite element model based on the displacement diagram and the arcsine formula; and to obtain the torsional stiffness of the frame based on the torsional angle.

[0137] This invention constructs a finite element model of a work machinery, constrains the degrees of freedom of a first constraint point located at the lower flange of the first longitudinal beam in the finite element model in the first and third directions, constrains the degrees of freedom of a second constraint point located at the lower flange of the second longitudinal beam in the finite element model in the first, second, and third directions, and constrains the degrees of freedom of a third constraint point located at the central axis of the crossbeam in the finite element model in the third direction. Forces of the same magnitude but opposite directions are applied to a first loading point located at the lower flange of the first longitudinal beam and a second loading point located at the lower flange of the second longitudinal beam in the finite element model, respectively. The direction of the force applied at the first loading point is either the third direction or the opposite direction of the third direction. After obtaining the displacement diagram of the deformed finite element model, the torsional stiffness of the work machinery's frame is obtained based on the displacement diagram. This avoids problems such as over-constraint and structural stress over-yielding in the finite element model of the work machinery during the determination of torsional stiffness, reduces calculation errors, and allows for more accurate and efficient determination of the torsional stiffness of the work machinery's frame.

[0138] Figure 6 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 6 As shown, the electronic device may include a processor 610, a communications interface 620, a memory 630, and a communication bus 640. The processor 610, communications interface 620, and memory 630 communicate with each other via the communication bus 640. The processor 610 can call logical instructions from the memory 630 to execute a torsional stiffness determination method and / or

[0139] The frame design method includes: constructing a finite element model of the operating machinery; constraining the degrees of freedom of the first constraint point in the finite element model in the first and third directions, constraining the degrees of freedom of the second constraint point in the finite element model in the first, second, and third directions, constraining the degrees of freedom of the third constraint point in the finite element model in the third direction, applying forces of the same magnitude but opposite directions to the first and second loading points in the finite element model to obtain the deformed finite element model; wherein, the first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; the third constraint point is located at the central axis of the crossbeam in the finite element model; the direction of the force applied at the first loading point is either the third direction or the opposite direction of the third direction; obtaining the displacement diagram of the deformed finite element model, and obtaining the torsional stiffness of the frame of the operating machinery based on the displacement diagram. The torsional stiffness of the frame to be designed is obtained based on the torsional stiffness determination method described above; the structural strength of the frame to be designed is obtained based on the torsional stiffness of the frame to be designed; and the design scheme of the frame to be designed is obtained based on the torsional stiffness and structural strength of the frame to be designed.

[0140] Furthermore, the logical instructions in the aforementioned memory 630 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0141] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to execute the torsional stiffness determination method and / or frame design method provided by the above methods. The above methods include: constructing a finite element model of the working machinery; constraining the degrees of freedom of a first constraint point in the finite element model in a first direction and a third direction; constraining the degrees of freedom of a second constraint point in the finite element model in the first direction, the second direction, and a third direction; and constraining the degrees of freedom of a third constraint point in the finite element model in a third direction. The degrees of freedom are determined by applying forces of equal magnitude but opposite direction at the first and second loading points in the finite element model to obtain the deformed finite element model. The first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; the third constraint point is located at the central axis of the crossbeam in the finite element model; the direction of the force applied at the first loading point is either the third direction or the opposite direction. The displacement diagram of the deformed finite element model is obtained, and based on the displacement diagram, the torsional stiffness of the frame of the working machinery is obtained. The torsional stiffness of the frame to be designed is obtained based on the torsional stiffness determination method described above; the structural strength of the frame to be designed is obtained based on the torsional stiffness of the frame to be designed; and the design scheme of the frame to be designed is obtained based on the torsional stiffness and structural strength of the frame to be designed.

[0142] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the torsional stiffness determination method and / or frame design method provided by the above methods. The methods include: constructing a finite element model of the working machinery; constraining the degrees of freedom of a first constraint point in the finite element model in a first direction and a third direction; constraining the degrees of freedom of a second constraint point in the finite element model in the first direction, a second direction, and a third direction; constraining the degrees of freedom of a third constraint point in the finite element model in a third direction; applying forces of the same magnitude but opposite directions to a first loading point and a second loading point in the finite element model, respectively, to obtain a deformed finite element model; wherein the first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; the third constraint point is located at the central axis of the crossbeam in the finite element model; the direction of the force applied at the first loading point is either a third direction or the opposite direction to the third direction; obtaining a displacement diagram of the deformed finite element model; and obtaining the torsional stiffness of the frame of the working machinery based on the displacement diagram. The torsional stiffness of the frame to be designed is obtained based on the torsional stiffness determination method described above; the structural strength of the frame to be designed is obtained based on the torsional stiffness of the frame to be designed; and the design scheme of the frame to be designed is obtained based on the torsional stiffness and structural strength of the frame to be designed.

[0143] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0144] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of various embodiments or some parts of embodiments.

[0145] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for determining torsional stiffness, characterized in that, include: Construct a finite element model of the operating machinery; The first constraint point in the finite element model is constrained in its degrees of freedom in the first and third directions; the second constraint point in the finite element model is constrained in its degrees of freedom in the first, second, and third directions; and the third constraint point in the finite element model is constrained in its degrees of freedom in the third direction. Forces of equal magnitude and opposite directions are applied to the first and second loading points in the finite element model to obtain the deformed finite element model. The first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; and the third constraint point is located at the central axis of the crossbeam in the finite element model. The direction of the force applied at the first loading point is the same as that applied at the third loading point. The direction is the opposite of the third direction; the lower flange of the first longitudinal beam and the lower flange of the second longitudinal beam are respectively located on both sides of the finite element model and are symmetrically distributed along the central axis of the front axis of the finite element model; the third constraint point is located on the central axis of the first crossbeam in the finite element model, the first crossbeam being the crossbeam located at the front of the finite element model; the third constraint point is located on the central axis of the second crossbeam in the finite element model, the second crossbeam being the crossbeam located at the rear of the finite element model; the first direction is a horizontal forward direction parallel to the forward direction of the working machinery or a horizontal backward direction parallel to the body of the working machinery, the second direction is a horizontal rightward direction perpendicular to the first direction, and the third direction is a direction perpendicular to the horizontal plane and upward; Obtain the displacement diagram of the deformed finite element model, and based on the displacement diagram, obtain the torsional stiffness of the frame of the operating machinery.

2. The method for determining torsional stiffness according to claim 1, characterized in that, The step of obtaining the torsional stiffness of the frame of the operating machinery based on the displacement diagram specifically includes: Based on the displacement diagram, the torsional angle of the frame of the finite element model is obtained according to the arcsine formula; The torsional stiffness of the vehicle frame is obtained based on the torsion angle.

3. The method for determining torsional stiffness according to claim 1 or 2, characterized in that, The number of the third constraint points is multiple.

4. A frame design method, characterized in that, include: The torsional stiffness of the vehicle frame to be designed is obtained based on the torsional stiffness determination method as described in any one of claims 1 to 3. Based on the torsional stiffness of the frame to be designed, the structural strength of the frame to be designed is obtained; Based on the torsional stiffness and structural strength of the chassis to be designed, a design scheme for the chassis to be designed is obtained.

5. A vehicle frame, characterized in that, The chassis is designed based on the chassis design method as described in claim 4.

6. A type of operating machinery, characterized in that, include: The frame as described in claim 5.

7. A vehicle frame design device, characterized in that, include: The stiffness acquisition module is used to acquire the torsional stiffness of the frame to be designed based on the torsional stiffness determination method as described in any one of claims 1 to 3. The strength acquisition module is used to acquire the structural strength of the frame to be designed based on the torsional stiffness of the frame to be designed; The chassis design module is used to obtain the design scheme of the chassis to be designed based on the torsional stiffness and structural strength of the chassis to be designed.

8. A device for determining torsional stiffness, characterized in that, include: The model building module is used to build finite element models of the operating machinery; A deformation loading module is used to constrain the degrees of freedom of a first constraint point in the finite element model in a first direction and a third direction, constrain the degrees of freedom of a second constraint point in the finite element model in the first direction, the second direction, and the third direction, and constrain the degree of freedom of a third constraint point in the finite element model in the third direction. Forces of equal magnitude and opposite directions are applied to the first loading point and the second loading point in the finite element model to obtain a deformed finite element model. The first constraint point and the first loading point are located at the lower flange of the first longitudinal beam in the finite element model; the second constraint point and the second loading point are located at the lower flange of the second longitudinal beam in the finite element model; the third constraint point is located at the central axis of the crossbeam in the finite element model; and the direction of the force applied at the first loading point is specified. The third direction is the direction of the third direction or the opposite direction of the third direction; the lower flange of the first longitudinal beam and the lower flange of the second longitudinal beam are respectively located on both sides of the finite element model and are symmetrically distributed along the central axis of the front axis of the finite element model; the third constraint point is located on the central axis of the first crossbeam in the finite element model, the first crossbeam is the crossbeam located at the front of the finite element model; the third constraint point is located on the central axis of the second crossbeam in the finite element model, the second crossbeam is the crossbeam located at the rear of the finite element model; the first direction is a horizontal forward direction parallel to the forward direction of the working machinery or a horizontal backward direction parallel to the body of the working machinery, the second direction is a horizontal rightward direction perpendicular to the first direction, and the third direction is a direction perpendicular to the horizontal plane and upward; The stiffness determination module is used to obtain the displacement diagram of the deformed finite element model, and based on the displacement diagram, to obtain the torsional stiffness of the frame of the operating machinery.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the torsional stiffness determination method as described in any one of claims 1 to 3, and / or the frame design method as described in claim 4.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the torsional stiffness determination method as described in any one of claims 1 to 3, and / or the frame design method as described in claim 4.

11. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the torsional stiffness determination method as described in any one of claims 1 to 3, and / or the frame design method as described in claim 4.

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