Loader work implement motion interference checking method and system

Abstract

The application discloses a loader working device motion interference checking algorithm and system, comprising the following steps: obtaining each hinge point coordinate and corresponding parameters such as pin shaft diameter at the position; generating a two-dimensional profile of the working device according to the hinge point coordinate and corresponding parameters such as pin shaft diameter at the position; determining the interference-prone position according to design experience, calculating the minimum distance of the interference-prone curve pair under the current posture; comparing the minimum distance between the calculated curves with the minimum gap value allowed by design, and if the minimum distance of the curve pair is smaller than the minimum gap allowed, recording the length of the dump cylinder and the boom cylinder under the current posture; when the length of the dump cylinder and / or the boom cylinder changes, the position of the profile is updated, and then the above steps are repeated until the motion is completed. Compared with the prior art, the product development efficiency can be effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of loader optimization design technology, specifically relating to a method and system for checking motion interference of loader working device. Background Technology

[0002] Loaders complete various operations such as loading and unloading by controlling a series of actions of the working device. When the existing linkage parameters cannot meet the requirements, the working device needs to be optimized according to the new design input. At the same time, in order to ensure that the working device can operate normally, interference between the various parts of the working device during the movement process should be avoided.

[0003] Existing technologies, when optimizing the design of working devices, often use the circle drawing method to constrain the gaps of simple contours. This method tends to result in excessively large design margins. Furthermore, it is difficult to incorporate the gaps of more complex shapes into the constraint conditions. Instead, after confirming the parameters of the working linkage, a 3D model of the working device needs to be established, and interference during the movement of the working device needs to be checked using 3D modeling software. When interference exists between components, the design needs to be re-optimized, and this process needs to be repeated until all performance indicators in the design input and the requirements for component contour gaps are met simultaneously. This leads to low product development efficiency and a long cycle. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a method and system for checking motion interference of a loader working device. By establishing a parametric model of the two-dimensional contour of the working device, the problem of interference checking between components is transformed into a minimum distance calculation problem of the two-dimensional contour. At the same time, the parametric two-dimensional contour can be updated as the hinge point position changes. Compared with the prior art, this can effectively improve product development efficiency.

[0005] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0006] In a first aspect, the present invention provides a method for checking motion interference of a loader's working device, comprising:

[0007] Obtain the coordinates of each hinge point and parameters such as the pin diameter at the corresponding position;

[0008] Based on the coordinates of each hinge point and parameters such as the pin diameter at the corresponding position, a two-dimensional profile of the working device is generated.

[0009] Based on design experience, identify areas prone to interference and calculate the minimum distance between interference curves under the current attitude.

[0010] Compare the calculated minimum distance between the curve pairs with the design-allowed minimum clearance value. If the minimum distance between the curve pairs is less than the allowable minimum clearance, record the lengths of the tipping cylinder and boom cylinder in the current posture.

[0011] When the length of the tipping cylinder and / or boom cylinder changes, the position of the profile is updated, and then the above steps are repeated until the movement is completed.

[0012] Optionally, generating the two-dimensional contour of the working device based on the coordinates of each hinge point and parameters such as the diameter of the pin at the corresponding position specifically involves:

[0013] First, based on the pin diameter, draw circles with each hinge point as the center and the product of the pin diameter and a certain proportional coefficient as the radius;

[0014] Then, based on the characteristic dimensions of each component, draw the outlines of the key features;

[0015] Next, based on the tangency relationship, calculate the mathematical expression for the transition curve connecting the key feature contour and the circle centered at the hinge point.

[0016] Optionally, drawing the outline of key features based on the characteristic dimensions of each component specifically involves:

[0017] For the bucket, first determine the length L of the bottom plate. d1 L d2 And the vertical distance H between the center of the bucket and boom hinge and the main cutter plate c Draw the base plate and main blade plate, then according to the bucket height H d and the cutting edge angle ψ z Draw the side cutting edge;

[0018] For the tie rod, first draw a line segment connecting the hinge points at both ends of the tie rod. Then draw two line segments parallel to and symmetrical to this line segment, with the distance between the line segments equal to the width W of the tie rod. l ;

[0019] For the boom, first draw a line segment connecting the upper and lower hinge points of the boom, based on the length W of the seat beam section. z and width L z Construct a rounded rectangle parallel to the line segment, and then determine the offset angle ψ of the support beam. z Rotate the rounded rectangle around its geometric center, and then draw two parallel lines of length L to the upper side of the support beam. z Line segments a and b are given, and their distances from the upper side of the beam are W respectively. d1 W d2 Finally, construct a circle that is tangent to line segment a and passes through the two endpoints of line segment b.

[0020] Optionally, the step of determining the interference-prone areas based on design experience and calculating the minimum distance between interference-prone curves under the current attitude specifically involves:

[0021] First, the outline of each component is decomposed into primitives such as line segments and arcs: the key points of a line segment are its two endpoints, and the key points of an arc are the endpoints of the arc and the center of the circle.

[0022] Then, based on design experience, the curves corresponding to the easily interfered positions are marked, curve i A i B This represents the curve combination corresponding to the i-th easily interfered position, and the mathematical expression of the curve is calculated based on the coordinates of the key points;

[0023] Finally, by optimizing the algorithm, the following problem is solved to obtain the minimum distance between each pair of curves under the current pose.

[0024] min(x iA -x iB ) 2 +(y iA -y iB ) 2

[0025] stf(x iA ,y iA ) = 0

[0026] g(x iB ,y iA ) = 0

[0027] x iA,min ≤x iA ≤x iA,max

[0028] x iB,min ≤x iB ≤x iB,max

[0029] Among them, (x iA ,y iA ), (x iB ,y iB f(x) represents the points on the i-th group of interference curves that are prone to occur; iA ,y iA ), g(x iB ,y iB ) are the mathematical expressions for the i-th group of curves prone to interference; [x iA,min ,x iA,max ]、[x iB,min ,x iB,max ] represents the range of values ​​for the abscissa of the point on the i-th group of easily interfering curves.

[0030] Optionally, updating the position of the contour when the length of the tipping cylinder and / or boom cylinder changes specifically involves:

[0031] Based on the lengths of the tipping cylinder and boom cylinder, the kinematic formulas of the loader's working device are derived using the DH method or vector method. The rotation angles of components such as the bucket, tie rod, rocker arm, and boom relative to the initial posture, as well as the coordinates of each hinge point, are calculated.

[0032] Based on the calculated rotation angle of the component relative to the initial posture and the coordinates of each hinge point, the positions of the key points are calculated using the coordinate transformation matrix:

[0033] KP new =T(KP init -RP init )+RP new

[0034] Among them, KP init KP new These are the initial and updated coordinates of the key points, respectively; RP init RP new These are the initial and updated coordinates of the reference point, which is any hinge point on the same component as the key point; T is the coordinate transformation matrix.

[0035]

[0036] , where θ is the rotation angle of the component relative to its initial orientation.

[0037] In a second aspect, the present invention provides a motion interference detection system for a loader working device, including a storage medium and a processor;

[0038] The storage medium is used to store instructions;

[0039] The processor is configured to operate according to the instructions to perform the method according to any one of the first aspects.

[0040] Based on the design requirements, select the coordinates of the corresponding hinge points as design variables;

[0041] Use component clearances, along with other performance indicators, as objective or constraint functions.

[0042] The optimization algorithm is used for iterative solution. Each iteration requires the execution of the calculation steps described in the first aspect. When generating the two-dimensional contour of the working device by parameterization, except for the first iteration which requires the execution of all steps of parameterization of the working device contour, other iterations only require the execution of "calculating the mathematical expression of the transition curve connecting the key feature contour and the circle centered at the hinge point according to the tangency relationship".

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0044] Compared to existing technologies, this invention obtains the coordinates of each hinge point and parameters such as the pin diameter at the corresponding position; generates a two-dimensional profile of the working device based on these parameters; identifies areas prone to interference based on design experience and calculates the minimum distance between pairs of easily interfering curves in the current posture; compares the calculated minimum distance between the curves with the design-allowed minimum clearance value; if the minimum distance between the curve pairs is less than the allowable minimum clearance, records the lengths of the tipping cylinder and boom cylinder in the current posture; updates the profile position when the lengths of the tipping cylinder and / or boom cylinder change, and then repeats the above steps until the movement is complete. By establishing a parameterized model of the two-dimensional profile of the working device, the problem of interference inspection between components is transformed into a problem of calculating the minimum distance of the two-dimensional profile. Furthermore, the parameterized two-dimensional profile can be updated as the hinge point positions change, effectively improving product development efficiency. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0046] Figure 1 This is a flowchart of a method for checking motion interference of a loader working device according to an embodiment of the present invention;

[0047] Figure 2 This is a schematic diagram of the two-dimensional outline of a loader working device according to an embodiment of the present invention;

[0048] Figure 3 This is a schematic diagram of key points of the bucket in one embodiment of the present invention. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0050] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0051] The method in the embodiments of the present invention will be described in detail below with reference to a specific implementation method.

[0052] like Figure 1 As shown, the method for checking motion interference of the loader working device includes the following steps:

[0053] Step (1): Obtain the coordinates of each hinge point and the corresponding pin diameter and other parameters.

[0054] Step (II): Based on the coordinates of each hinge point and parameters such as the pin diameter at the corresponding position, generate the two-dimensional profile of the working device, specifically as follows:

[0055] First, based on the pin diameter, draw circles with each hinge point as the center and the product of the pin diameter and a certain proportional coefficient as the radius;

[0056] Then, based on the characteristic dimensions of each component, draw the outline of the key features: for the bucket, first, based on the length L of the bottom plate... d1 L d2 And the vertical distance H between the center of the bucket and boom hinge and the main cutter plate c Draw the base plate and main blade plate, then according to the bucket height H d and the cutting edge angle ψ z Draw the side cutting edge; for the tie rod, first draw a line segment connecting the hinge points at both ends of the tie rod, and then draw two line segments parallel to and symmetrical to this line segment, with the distance between the line segments equal to the width W of the tie rod. l For the boom, first draw a line segment connecting the upper and lower hinge points of the boom, based on the length W of the seat beam section. z and width L z Construct a rounded rectangle parallel to the line segment, and then determine the offset angle ψ of the support beam. z Rotate the rounded rectangle around its geometric center, and then draw two parallel lines of length L to the upper side of the support beam. z Line segments a and b are given, and their distances from the upper side of the beam are W respectively. d1 W d2Finally, construct a circle that is tangent to line segment a and passes through the two endpoints of line segment b.

[0057] Based on the tangency relationship, calculate the mathematical expression for the transition curve connecting the key feature contour and the circle centered at the hinge point.

[0058] The final two-dimensional contour of the working device is as follows: Figure 2 As shown.

[0059] Step (3): Based on design experience, determine the areas prone to interference and calculate the minimum distance between the interference curves under the current attitude. Specifically:

[0060] First, the outline of each component is decomposed into graphic elements such as line segments and arcs: the key points of a line segment are its two endpoints, and the key points of an arc are the endpoints of the arc and the center. Taking the bucket as an example, its outline key points are as follows: Figure 3 As shown.

[0061] Then, based on design experience, the curves corresponding to the easily interfered positions are marked, curve i A i B This represents the curve combination corresponding to the i-th easily interfered position, and the mathematical expression of the curve is calculated based on the coordinates of the key points;

[0062] Finally, by optimizing the algorithm, the following problem is solved to obtain the minimum distance between each pair of curves under the current pose.

[0063] min(x iA -x iB ) 2 +(y iA -y iB ) 2

[0064] stf(x iA ,y iA ) = 0

[0065] g(x iB ,y iA ) = 0

[0066] x iA,min ≤x iA ≤x iA,max

[0067] x iB,min ≤x iB ≤x iB,max

[0068] Among them, (x iA ,y iA ), (x iB ,y iB f(x) represents the points on the i-th group of interference curves that are prone to occur;iA ,y iA ), g(x iB ,y iB ) are the mathematical expressions for the i-th group of curves prone to interference; [x iA,min ,x iA,max ]、[x iB,min ,x iB,max ] represents the range of values ​​for the abscissa of the point on the i-th group of easily interfering curves.

[0069] Step (iv) Compare the calculated minimum distance of the curve pair with the design-allowed minimum clearance value. If the minimum distance of the curve pair is less than the allowable minimum clearance, record the length of the tipping cylinder and boom cylinder in the current posture.

[0070] Step (5) When the length of the tipper cylinder and / or boom cylinder changes, the position of the contour is updated, specifically as follows:

[0071] Based on the lengths of the tipping cylinder and boom cylinder, the rotation angles of components such as the bucket, tie rod, rocker arm, and boom relative to the initial posture, as well as the coordinates of each hinge point, are calculated using the vector method.

[0072] Based on the calculated rotation angle of the component relative to the initial posture and the coordinates of each hinge point, the positions of the key points are calculated using the coordinate transformation matrix:

[0073] KP new =T(KP init -RP init )+RP new

[0074] Among them, KP init KP new These are the initial and updated coordinates of the key points, respectively; RP init RP new These are the initial and updated coordinates of the reference point, which is any hinge point on the same component as the key point; T is the coordinate transformation matrix.

[0075]

[0076] Where θ is the rotation angle of the component relative to its initial orientation.

[0077] Step (VI) Repeat steps (III) to (V) until the exercise is completed.

[0078] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0079] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0080] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0081] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0082] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

[0083] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for checking motion interference of a loader's working device, characterized in that, include: Obtain the coordinates of each hinge point and the corresponding pin diameter parameters; Based on the coordinates of each hinge point and the pin diameter parameters at the corresponding positions, a two-dimensional profile of the working device is generated. Based on design experience, identify areas prone to interference and calculate the minimum distance between interference curves under the current attitude. Compare the calculated minimum distance between the curve pairs with the design-allowed minimum clearance value. If the minimum distance between the curve pairs is less than the allowable minimum clearance, record the lengths of the tipping cylinder and boom cylinder in the current posture. When the length of the tipping cylinder and / or boom cylinder changes, the position of the contour is updated, and then the above steps are repeated until the movement is completed; The update of the contour position when the length of the tipping cylinder and / or boom cylinder changes is specifically as follows: Based on the lengths of the tipping cylinder and boom cylinder, the kinematic formulas of the loader's working device are derived using the DH method or vector method. The rotation angles of the bucket, tie rod, rocker arm, and boom components relative to the initial posture, as well as the coordinates of each hinge point, are calculated. Based on the calculated rotation angle of the component relative to the initial posture and the coordinates of each hinge point, the positions of the key points are calculated using the coordinate transformation matrix: ， Among them, KP init KP new These are the initial and updated coordinates of the key points, respectively; RP init RP new These are the initial and updated coordinates of the reference point, which is any hinge point on the same component as the key point; T is the coordinate transformation matrix. ， Where θ is the rotation angle of the component relative to its initial orientation.

2. The method for checking motion interference of a loader working device according to claim 1, characterized in that, The step of generating a two-dimensional profile of the working device based on the coordinates of each hinge point and the pin diameter parameters at the corresponding positions is as follows: First, based on the pin diameter, draw circles with each hinge point as the center and the product of the pin diameter and a certain proportional coefficient as the radius; Then, based on the characteristic dimensions of each component, draw the outlines of the key features; Next, based on the tangency relationship, calculate the mathematical expression for the transition curve connecting the key feature contour and the circle centered at the hinge point.

3. The method for checking motion interference of a loader working device according to claim 2, characterized in that: The key features are outlined based on the characteristic dimensions of each component, specifically based on the characteristic dimensions of the bucket, the tie rod, and the boom.

4. The method for checking motion interference of a loader working device according to claim 3, characterized in that: Based on the characteristic dimensions of the bucket, draw the outline of the key features, specifically: first, based on the length L of the bottom plate... d1 L d2 And the vertical distance H between the center of the bucket and boom hinge and the main cutter plate c Draw the base plate and main blade plate, then according to the bucket height H d and the cutting edge angle ψ z Draw the side cutting edge.

5. The method for checking motion interference of a loader working device according to claim 3, characterized in that: Based on the characteristic dimensions of the tie rod, draw the outline of the key features. Specifically, first, draw a line segment connecting the hinge points at both ends of the tie rod. Then, draw two line segments parallel to and symmetrical to this line segment, with the distance between the line segments equal to the width W of the tie rod. l .

6. The method for checking motion interference of a loader working device according to claim 3, characterized in that: Based on the characteristic dimensions of the boom, draw the outline of the key features, specifically: first, draw a line segment connecting the upper and lower hinge points of the boom; then, based on the length W of the seat beam section... z and width L z Construct a rounded rectangle parallel to the line segment, and then determine the offset angle ψ of the support beam. z Rotate the rounded rectangle around its geometric center, and then draw two line segments a and b, parallel to the upper side of the support beam, with length Lz, and distances W from the upper side of the support beam respectively. d1 W d2 Finally, construct a circle that is tangent to line segment a and passes through the two endpoints of line segment b.

7. The method for checking motion interference of a loader working device according to claim 1, characterized in that: The process involves identifying areas prone to interference based on design experience and calculating the minimum distance between interference-prone curves under the current attitude. Specifically: First, the outline of each component is decomposed into line segments and arc primitives: the key points of a line segment are its two endpoints, and the key points of an arc are the endpoints of the arc and the center of the circle. Then, based on design experience, the curves corresponding to the easily interfered positions are marked, and the mathematical expression of the curves is calculated based on the coordinates of the key points; Finally, the following problem is solved by optimizing the algorithm to obtain the minimum distance between each pair of curves under the current pose; min , s.t. , ， ， ， Among them, curve i A i B This represents the curve combination corresponding to the i-th easily interfered position, (x iA ,y iA ), (x iB ,y iB f(x) represents the points on the i-th group of interference curves that are prone to occur; iA ,y iA ), g(x iB ,y iB ) are the mathematical expressions for the i-th group of curves prone to interference; [x iA,min ,x iA,max ]、[x iB,min ,x iB,max ] represents the range of values ​​for the abscissa of the point on the i-th group of easily interfering curves.

8. A motion interference detection system for a loader working device, characterized in that, Including storage media and processor; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the method according to any one of claims 1-7; Based on the design requirements, select the coordinates of the corresponding hinge points as design variables; Use component clearances, along with other performance indicators, as objective or constraint functions. The optimization algorithm is used for iterative solution. Each iteration requires the execution of the calculation steps described in claim 1. When generating the two-dimensional contour of the working device by parameterization, except for the first iteration which requires the execution of all the steps described in claim 2, the other iterations only require the execution of the mathematical expression of the transition curve connecting the key feature contour and the circle centered at the hinge point, according to the tangent relationship described in claim 2.

Images