Partitioning and calculating method for bulk material grabbing operation range of material grabbing machine

Abstract

The invention relates to an operation range partitioning and calculating method for bulk material grabbing of a grabbing machine, belongs to the technical field of material carrying, and aims to improve grabbing efficiency and safety and reduce energy consumption. According to the method, a coordinate system of a material grabbing machine is established, the maximum grabbing range and the minimum grabbing range are determined, and therefore an operable area, an unsafe area, a low-efficiency grabbing area and a suggested grabbing area are divided. A material pile surface point set is obtained through a sensing sensor, intersection operation is conducted on the material pile surface point set and the safe operation area point set, and a grabbable area point set is obtained. Furthermore, a suggested grabbing area point set is obtained by performing complementary set operation with the low-efficiency grabbing area point set. Through reasonable partitioning and calculation, support is provided for motion planning and task scheduling of the working arm of the material grabbing machine, the grabbing efficiency and safety are effectively improved, energy consumption is reduced, and intelligent operation is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of material handling, and relates to a method for dividing an operation range and calculating a method for grabbing bulk materials by a grabber. Background Art

[0002] Traditional material grabber operations mainly rely on manual experience, lacking detailed division of the operating scope and targeted research. This leads to the following problems in the operation of the material grabber:

[0003] The grabbing action of the grabber is blind and it is unable to accurately locate the best grabbing point, resulting in low grabbing efficiency and quality, and easily causing waste of bulk materials.

[0004] The unclear division of the operating range of the material grabber makes it easy for safety accidents such as collision and falling to occur, causing damage to personnel and equipment.

[0005] Improper motion path planning of the grabber leads to unnecessary movements and energy consumption, increasing operating costs.

[0006] In order to solve the above problems, it is necessary to scientifically divide the operating range of bulk material grabbing by the grabber, and conduct targeted research and optimization to improve the grabbing efficiency, safety, and reduce energy consumption. Summary of the invention

[0007] In view of this, the purpose of the present invention is to provide a method for zoning and calculating the working range of bulk material grabbing by a material grabber. A material grabber coordinate system is established, and an operating range that is approximately spherical is constructed according to the physical characteristics of the material grabber. Then, the inefficient operating area and the unsafe area are refined based on manual operation experience. The surface point set of the bulk material pile is obtained through the perception sensor, and then the recommended grabbing area of ​​the material grabber can be obtained through the intersection of the refined operating range and the material pile point set.

[0008] In order to achieve the above object, the present invention provides the following technical solutions:

[0009] A method for partitioning and calculating the working range of a bulk material grabbing machine, the method comprising the following steps:

[0010] Establish the coordinate system of the material grabber, with the center of the material grabber as the origin of the coordinate system, the front of the rotary platform as the positive direction of the x-axis, and use the right-hand rule to determine the y-axis and z-axis;

[0011] Determine the maximum graspable range, which is a sphere with the center point of the grabber as the center and the maximum graspable radius as the radius;

[0012] Determine the minimum graspable range, which is a sphere with the center point of the grabber as the center and the minimum graspable radius as the radius;

[0013] Calculate the operable area point set, which is the complement of the maximum graspable range point set relative to the minimum graspable range point set;

[0014] Calculate the unsafe area point set, which is the complement of the spherical cone relative to the minimum graspable range. The bottom radius of the spherical cone is equal to the maximum graspable radius, and the height of the spherical cone is adjustable.

[0015] Calculate the safe operation area point set, which is the complement of the operational area point set relative to the unsafe area point set;

[0016] Obtaining a point set on the surface of the pile;

[0017] Calculate the grabbable area point set, which is the intersection of the safe operation area point set and the pile surface point set;

[0018] Determine the inefficient grasping area, which is a cuboid with length and width equal to the maximum graspable radius, adjustable height, and intersecting with the operable area point set;

[0019] The proposed grasping area point set is calculated as the complement of the graspable area point set and the inefficient grasping area point set.

[0020] Furthermore, the ratio of the spherical cone height to the spherical crown height of the unsafe area point set is adjustable.

[0021] Furthermore, the height of the inefficient gripping area is adjustable.

[0022] Furthermore, the maximum graspable radius is r 最大 , all points (x, y, z) in the sphere satisfy the following conditions: 2 +y 2 +z 2 ≤r 最大 2 , and z ≥ 0, we get the point set S within the maximum graspable range 最大可抓取 ;

[0023] The minimum graspable radius is r 最小 , all points (x, y, z) in the sphere satisfy the following conditions: 2 +y 2 +z 2 ≤r 最小 2 , and z ≥ 0, we get the point set S within the minimum graspable range 最小可抓取 ;

[0024] The operable area point set meets the following conditions: S 可运行 =S 最大可抓取 -S 最小可抓取 ; S 最大可抓取 represents the point set with the maximum graspable range, S 最小可抓取 The point set representing the minimum graspable range; r 最小2 <x 2 +y 2 +z 2 ≤r 最大 2 and z ≥ 0;

[0025] The set of points inside the cone is expressed as (x = r*cos(θ)*(1-z / h), y = r*sin(θ)*(1-z / h), z = k*h), where h is the height of the spherical cap, θ is the polar angle of the point on the bottom surface of the spherical cap, r is the distance from any point on the bottom surface of the spherical cone to the center of the sphere, and k is a constant between [0,1], indicating the ratio of the height of the cone to the height of the spherical cap. The set of points in the unsafe area S 不安全 The following conditions are met:

[0026] (S 不安全 =(x=r*cos(θ)*(1-z / h), y=r*sin(θ)*(1-z / h), z=k*h), and x 2 +y 2 +z 2 >r 最小 2 and z ≥ 0;

[0027] Safe operation area point set S 可安全运行 The following conditions are met:

[0028] r 最小 2 <x 2 +y 2 +z 2 ≤r 最大 2 And (x,y,z){(x=r*cos(θ)*(1-z / h), y=r*sin(θ)*(1-z / h), z=k*h), and

[0029] x 2 +y 2 +z 2 >r 最小 2 , and z ≥ 0};

[0030] Determine the inefficient grasping area S 低效抓取 , is a cuboid, and the points (x, y, z) inside the cuboid satisfy the following conditions: 最大 ≤x≤r 最大 , -r 最大 ≤y≤r 最大 , 0≤z≤h 低效抓取 ; The length and width of the cuboid are both r 最大 , height is h 低效抓取 ;

[0031] Point set S of the graspable area 可抓取 Satisfaction: S 可抓取 =S 可安全运行 ∩S 料堆 ; S 料堆 It is a material stockpile point collection;

[0032] Suggested grab area point set S 建议抓取 Satisfaction: S 建议抓取 =S 可抓取 -S 低效抓取 .

[0033] The beneficial effects of the present invention are:

[0034] (1) By dividing the working range of the grabber and calculating the optimal grabbing area, the grabber can accurately locate the optimal grabbing point, improve the grabbing efficiency and quality, and reduce the waste of bulk materials.

[0035] (2) By dividing the unsafe area and restricting the operation of the grabber in this area, safety accidents such as collision and falling can be effectively avoided, ensuring the safety of personnel and equipment.

[0036] (3) By optimizing the motion path planning of the grabber, unnecessary movements and energy consumption can be reduced, operating costs can be reduced, and economic benefits can be improved.

[0037] (4) The present invention provides a basis for the intelligent operation of the grabber, which can realize the automatic planning of the grabbing path and the automatic control of the grabbing action, thereby improving the operation efficiency and safety.

[0038] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0040] Figure 1 It is a schematic diagram of the principle of the present invention;

[0041] Figure 2 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0042] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0043] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0044] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0045] like Figure 1 As shown in the figure, the bulk material grabbing operation area of ​​the grabber is divided into an operable area, an unsafe area, an inefficient grabbing area and a recommended grabbing area. The definitions of each area are as follows:

[0046] Runnable area (such as Figure 1 The middle blue area is the area where the grabber’s arm can move normally.

[0047] Unsafe areas (such as Figure 1 In the process of grabbing bulk materials, there is a possibility of bulk materials falling. In order to prevent safety accidents, this area is calculated through experiments.

[0048] Inefficient grasping areas (such as Figure 1 The middle yellow area is the area where the gripper has lower gripping efficiency and quality.

[0049] Suggested crawling area (such as Figure 1 The middle green area is the area on the pile where the grabber has higher grab efficiency and quality.

[0050] like Figure 2 As shown, the calculation method for each area is as follows:

[0051] Take the center of the grabber as the coordinate origin, the front of the rotary platform as the positive direction of the x-axis, and use the right-hand rule to establish the grabber coordinate system. All the following points use this coordinate system.

[0052] S1: The maximum grasping range is defined as the maximum range that the end point of the attachment can reach, which is a sphere with the center point of the gripper as the center of the sphere and the maximum grasping radius r 最大 is the radius, then all points (x, y, z) in the sphere satisfy the following conditions: 2 +y 2 +z 2 ≤r 最大 2 , and z ≥ 0, we get the point set S within the maximum graspable range 最大可抓取 ;

[0053] The minimum graspable range is defined as the minimum reachable range of the attachment end point, which is a sphere with a minimum graspable radius r 最小 is the radius, then all points (x, y, z) in the sphere satisfy the following conditions: 2 +y 2 +z 2 ≤r 最小 2 , and z ≥ 0, we can get the point set S within the minimum graspable range 最小可抓取 .

[0054] S2: Calculate the runnable area point set S 可运行 (like Figure 1 blue area), by calculating the point set S with the maximum graspable range 最大可抓取 The point set S with the minimum graspable range 最小可抓取 The complement of is: S 可运行 =S 最大可抓取 -S 最小可抓取 , that is, r 最小 2 <x 2 +y 2 +z 2 ≤r 最大 2 , and z≥0.

[0055] S3: Calculate the point set S of the safe operating area 可安全运行 , by calculating the operable area point set S 可运行 Relatively unsafe area point set S 不安全 The complement of is: S 可安全运行 =S 可运行 -S 不安全 .

[0056] Unsafe areas such as Figure 1 The red area is the complement of a cone relative to the minimum graspable range (sphere). The set of points inside the cone can be expressed as (x = r*cos(θ)*(1-z / h), y = r*sin(θ)*(1-z / h), z = k*h), where h is the height of the spherical cap, θ is the polar angle of the point on the bottom of the spherical cap, r is the distance from any point on the bottom of the cone to the center of the sphere, and k is a constant between [0,1], which represents the ratio of the height of the cone to the height of the spherical cap. We can get S 不安全 =(x=r*cos(θ)*(1-z / h), y=r*sin(θ)*(1-z / h), z=k*h), and x 2 +y 2 +z 2 >r 最小 2 And z≥0.

[0057] S 可安全运行 Represented as r 最小 2 <x 2 +y 2 +z 2 ≤r 最大 2 , and (x,y,z){(x=r*cos(θ)*(1-z / h), y=r*sin(θ)*(1-z / h),

[0058] z=k*h), and x 2 +y 2 +z 2 >r 最小 2 , and z≥0}.

[0059] S4: Calculate the point set S of the graspable area 可抓取 , by calculating the safe area point set S 可安全运行 and material pile point set S 料堆 The intersection of gets: S 可抓取 =S 可安全运行 ∩S 料堆 .

[0060] S5: Calculate the point set S of the proposed grasping area 建议抓取 , by calculating the graspable range point set S 可安全运行 Relatively inefficient grasping point set S 低效抓取 The complement of is: S 建议抓取 =S 可抓取 -S 低效抓取 .

[0061] S 低效抓取is a cuboid with the origin of the coordinate system as the center of the bottom surface (length and width are both r 最大 , height is h 低效抓取 , whose sides are perpendicular or parallel to the three axes of the coordinate system), and the points (x, y, z) in the cuboid satisfy (-r 最大 ≤x≤r 最大 , -r 最大 ≤y≤r 最大 , 0≤z≤h 低效抓取 ) and S 可运行 The intersection of .

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A method for dividing and calculating the working range of a bulk material grabbing machine, characterized in that: The method comprises the following steps: Establish the coordinate system of the material grabber, with the center of the material grabber as the origin of the coordinate system, the front of the rotary platform as the positive direction of the x-axis, and use the right-hand rule to determine the y-axis and z-axis; Determine the maximum graspable range, which is a sphere with the center point of the grabber as the center and the maximum graspable radius as the radius; Determine the minimum graspable range, which is a sphere with the center point of the grabber as the center and the minimum graspable radius as the radius; Calculate the operable area point set, which is the complement of the maximum graspable range point set relative to the minimum graspable range point set; Calculate the unsafe area point set, which is the complement of the spherical cone relative to the minimum graspable range. The bottom radius of the spherical cone is equal to the maximum graspable radius, and the height of the spherical cone is adjustable. Calculate the safe operation area point set, which is the complement of the operational area point set relative to the unsafe area point set; Obtaining a point set on the surface of the pile; Calculate the grabbable area point set, which is the intersection of the safe operation area point set and the pile surface point set; Determine the inefficient grasping area, which is a cuboid with length and width equal to the maximum graspable radius, adjustable height, and intersecting with the operable area point set; The proposed grasping area point set is calculated as the complement of the graspable area point set and the inefficient grasping area point set.

2. The method for dividing the working range and calculating the bulk material grabbing operation of the grabber according to claim 1 is characterized in that: The ratio of the spherical cone height to the spherical crown height of the unsafe area point set is adjustable.

3. The method for dividing the working range and calculating the bulk material grabbing operation of the grabber according to claim 1 is characterized in that: The low-efficiency gripping area is height-adjustable.

4. The method for dividing the working range and calculating the working range of bulk material grabbing by a grabber according to claim 1 is characterized in that: The maximum graspable radius is r 最大 , all points (x, y, z) in the sphere satisfy the following conditions: 2 +y 2 +z 2 ≤r 最大 2 , and z ≥ 0, we get the point set S within the maximum graspable range 最大可抓取 ; The minimum graspable radius is r 最小 , all points (x, y, z) in the sphere satisfy the following conditions: 2 +y 2 +z 2 ≤r 最小 2 , and z ≥ 0, we get the point set S within the minimum graspable range 最小可抓取 ; The operable area point set meets the following conditions: S 可运行 =S 最大可抓取 -S 最小可抓取 ; S 最大可抓取 represents the point set with the maximum graspable range, S 最小可抓取 The point set representing the minimum graspable range; r 最小 2 <x 2 +y 2 +z 2 ≤r 最大 2 and z ≥ 0; The set of points inside the cone is expressed as (x = r*cos(θ)*(1-z / h), y = r*sin(θ)*(1-z / h), z = k*h), where h is the height of the spherical cap, θ is the polar angle of the point on the bottom surface of the spherical cap, r is the distance from any point on the bottom surface of the spherical cone to the center of the sphere, and k is a constant between [0,1], indicating the ratio of the height of the cone to the height of the spherical cap. The set of points in the unsafe area S 不安全 The following conditions are met: (S 不安全 =(x = r * cos(θ) * (1 - z / h), y = r * sin(θ) * (1 - z / h), z = k * h), and x 2 + y 2 + z 2 > r 最小 2 and z ≥ 0; Safe operation area point set S 可安全运行 The following conditions are met: r 最小 2 <x 2 +y 2 +z 2 ≤r 最大 2 and (x, y, z) {(x = r * cos(θ) * (1 - z / h), y = r * sin(θ) * (1 - z / h), z = k * h), and x 2 +y 2 +z 2 >r 最小 2 , and z ≥ 0}; Determine the inefficient grasping area S 低效抓取 , is a cuboid, and the points (x, y, z) inside the cuboid satisfy the following conditions: 最大 ≤x≤r 最大 , -r 最大 ≤y≤r 最大 , 0≤z≤h 低效抓取 ; The length and width of the cuboid are both r 最大 , height is h 低效抓取 ; Point set S of the graspable area 可抓取 Satisfaction: S 可抓取 =S 可安全运行 ∩S 料堆 ; S 料堆 It is a material stockpile point collection; Suggested grab area point set S 建议抓取 Satisfaction: S 建议抓取 =S 可抓取 -S 低效抓取 .

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