Manipulator control system for injection molding machine

Abstract

The invention discloses a manipulator control system for an injection molding machine, which relates to the field of manipulator control and comprises a main body part, an injection molding product grabbing assembly, a data acquisition module, a data processing module and a control module. Through an image processing technology, the gravity center position of the injection molding product is analyzed by analyzing the image of the injection molding product, then the mechanical arm is controlled to move to the gravity center position of the injection molding product for grabbing, the stability of the injection molding product during grabbing is guaranteed, and the optimal grabbing radius of the injection molding product is obtained through image analysis of the injection molding product. According to the manipulator control system, under the condition that the injection molding product is not in the unique position and posture, the proper injection molding product grabbing position can still be found, and grabbing is stable.

Description

Technical Field

[0001] The invention relates to the field of robot control, and in particular to a robot control system for an injection molding machine. Background Art

[0002] As is known, the control system of the plastic machine robot is the key part of the entire robot operation, which is responsible for controlling the movement, grabbing and placing actions of the robot to ensure accurate and stable operation;

[0003] Since injection molded products need to be transferred during the production process, they need to be grasped by a robot and then transferred. Before the grasping and transfer, the position of the injection molded product is not a fixed position (it is often in different positions within a certain area) and is in different postures (different angles). Therefore, when the robot grasps it, the grasping position to which the robot moves is different. In the existing robot control systems of injection molding machines, some of them do not have a control system for "capturing" the position and posture of the injection molded products. These control systems require the injection molded products to be controlled to a fixed position and a fixed posture before they are grasped, which increases the steps in the production process and affects the production efficiency of the injection molded products. Some of them also have a control system for "capturing" the position of the injection molded products, but they can generally only move the robot claw to the relative position of the injection molded product, and cannot control the grasping position. Therefore, the stability is poor during grasping and transfer, and grasping abnormalities are prone to occur. Summary of the invention

[0004] (I) Purpose of the invention

[0005] In view of this, the object of the present invention is to provide a manipulator control system for an injection molding machine, which can ensure that when the injection molded product is not in a unique position and posture, a suitable grasping position for the injection molded product can still be found and the grasping is stable.

[0006] (II) Technical solution

[0007] To achieve the above technical purpose, the present invention provides a manipulator control system for an injection molding machine, which includes a main body, which is composed of a first large arm, a second large arm and a forearm that are movably connected in sequence, forming a manipulator structure that can grasp injection molded products within an operating radius;

[0008] An injection molded product grabbing assembly, which is rotatably connected to the front end of the forearm through a bearing and is used to grab the injection molded product;

[0009] A data acquisition module, which is fixedly mounted on the front side of the forearm and is used to collect image information of the injection molded product;

[0010] a data processing module, which is arranged on the forearm, and is used to process the image information of the injection molded product, calculate the deviation value between the center of the injection molded product grasping component and the center of gravity of the injection molded product, determine whether the center of the injection molded product grasping component corresponds to the center of gravity of the injection molded product based on the deviation value, and if not, generate a first correction instruction, calculate the optimal grasping radius of the injection molded product, and generate a second correction instruction;

[0011] A control module is arranged on the forearm, and includes a first control submodule and a second control submodule, wherein the first control submodule is used to generate a first control instruction according to the first correction instruction, and perform a first correction operation on the injection molded product grasping component through the first control instruction, and the second control submodule is used to generate a second control instruction according to the second correction instruction, and control the injection molded product grasping component to perform a second correction operation through the second control instruction.

[0012] As a further description of the above technical solution: the method for calculating the deviation value between the geometric center of gravity position of the injection molded product and the center position of the injection molded product grabbing component is as follows:

[0013] Take any point in the contour image of the injection molded product as the coordinate origin and any dimension as the unit distance to establish a plane XY rectangular coordinate system, and obtain the coordinates of each corner point in the contour image of the injection molded product, which are set as A1(x1,y1), A2(x2,y2), ... A n (x n ,y n ), then the coordinate calculation method of the geometric center of gravity O(x, y) of the contour image of the injection molded product is as follows:

[0014]

[0015] Among them, x and y are the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the injection molded product contour image, respectively. i ,y i are the coordinates of the i-th corner point of the injection molded product contour image, and n is the total number of edges of the injection molded product contour image;

[0016] Project the center position of the injection molded product grabbing assembly onto the plane XY rectangular coordinate system to obtain the coordinates of the center position of the injection molded product grabbing assembly in the plane XY rectangular coordinate system, recorded as O′(x′, y′);

[0017] The calculation method of the deviation value Y between the geometric center of gravity of the injection molded product and the center position of the injection molded product grabbing component is as follows:

[0018]

[0019] Wherein, Y is the deviation value between the geometric center of gravity of the injection molded product and the center position of the injection molded product grabbing assembly, x′ and y′ are respectively the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the center position of the injection molded product grabbing assembly, and x and y are respectively the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the injection molded product contour image.

[0020] As a further description of the above technical solution: the method for obtaining the coordinates of the center position of the injection molded product grabbing component in the plane XY rectangular coordinate system is as follows:

[0021] The projection of the data acquisition module is mapped to the plane XY rectangular coordinate system, and the coordinates of the data acquisition module in the plane XY rectangular coordinate system are obtained, which is recorded as P(x0, y0). The coordinate calculation method of the center position O′(x′, y′) of the injection molding product grabbing component is as follows:

[0022]

[0023] Among them, x′ and y′ are the X-axis coordinates and Y-axis coordinates of the geometric center of gravity of the center position of the injection molded product grabbing assembly, x0 and y0 are the X-axis coordinates and Y-axis coordinates of the data acquisition module, l1 and l2 are the horizontal distance and vertical distance between the data acquisition module and the projection of the center position of the injection molded product grabbing assembly.

[0024] As a further description of the above technical solution: the method for determining whether the center of the injection molded product grabbing assembly corresponds to the center of gravity of the injection molded product is as follows:

[0025] The preset deviation threshold is Y1, then:

[0026] When Y≤Y1, it is determined that the center of the injection molded product grabbing assembly corresponds to the center of gravity of the injection molded product, and the first correction instruction is not generated;

[0027] When Y>Y1, it is determined that the center of the injection molded product grabbing assembly does not correspond to the center of gravity of the injection molded product, and a first correction instruction is generated.

[0028] As a further description of the above technical solution: the first control instruction includes a moving direction and a moving distance, wherein the moving direction is the direction from coordinate O to coordinate O′, and the moving distance is the deviation value Y.

[0029] As a further description of the above technical solution: the method for calculating the optimal gripping radius of the injection molded product is as follows:

[0030] The vertical distance from the geometric center of gravity of the contour image of the injection molded product to the nearest edge of the injection molded product is recorded as L, the safe distance that the injection molded product grasping component (6) needs to maintain with the edge of the injection molded product when grasping the injection molded product is recorded as L0, the grasping radius of the injection molded product grasping component (6) is recorded as R, and the maximum grasping radius of the injection molded product grasping component (6) is Rmax, then:

[0031] When L≥Rmax+L0, R=Rmax;

[0032] When L<Rmax+L0, R=L-L0.

[0033] As a further description of the above technical solution: the injection molded product grabbing assembly includes:

[0034] The movable seat adopts a cylindrical structure and is rotatably mounted on the forearm through a bearing. The bottom of the movable seat is provided with three assembly grooves in a circular array;

[0035] There are three claw rods in total, and a suction cup is movably installed at the bottom. The three claw rods are correspondingly rotatably installed in the assembly groove at the bottom of the movable seat through the rotating shaft;

[0036] A rotation control mechanism, which is disposed above the movable seat and is used to control the rotation angle of the movable seat;

[0037] The claw rod control mechanism is arranged in the movable seat and is used to control the opening radius of the claw rod.

[0038] As a further description of the above technical solution: the rotation control mechanism includes:

[0039] A fixing frame, which is fixedly mounted on the side of the forearm and has a motor installed inside;

[0040] a driving gear mounted on the output shaft of the motor;

[0041] The upper surface of the movable seat is provided with an annular groove along the circumferential direction, and the inner wall of the annular groove is embedded with a gear ring along the circumferential direction. The gear ring is meshed with the driving gear, so that when the driving gear rotates, the movable seat can be driven to rotate through the gear ring.

[0042] As a further description of the above technical solution: the claw lever control mechanism includes:

[0043] upper plate body;

[0044] A lower plate body, the center of which is fixedly connected to the upper plate body through a connecting rod, and a gap is provided between the upper plate body and the lower plate body;

[0045] A cylinder, which is fixedly mounted above the movable seat, and a piston rod of the cylinder is fixedly connected to the upper plate;

[0046] Among them, the end of the claw rod is connected with a curved rod, and the curved rod is inserted into the gap between the upper plate body and the lower plate body, so that when the upper plate body and the lower plate body move up and down, the curved rod drives the bottom of the claw rod to expand outward or retract inward.

[0047] As a further description of the above technical solution: the second control instruction includes a cylinder movement stroke, wherein the cylinder movement stroke is calculated as follows:

[0048] Assume that the gripping radius of the claw rod is R, the moving stroke of the cylinder is P, and the maximum allowable stroke of the cylinder is Pmax, where:

[0049] When R = Rmax, the cylinder's travel distance P = Pmax;

[0050] When R=L, the cylinder's travel distance P=kR.

[0051] In the above technical scheme, the present invention provides a manipulator control system for an injection molding machine, which analyzes the image of the injection molded product to determine the center of gravity of the injection molded product through image processing technology, and then controls the manipulator to move to the center of gravity of the injection molded product for grabbing, thereby ensuring the stability of the injection molded product during grabbing, and obtaining the optimal grabbing radius of the injection molded product through image analysis of the injection molded product. Therefore, the manipulator control system can ensure that when the injection molded product is not in a unique position and posture, a suitable grabbing position for the injection molded product can still be found, and the grabbing is stable. At the same time, the present invention enables the manipulator to be flexibly controlled through the structural design of the injection molded product grabbing component at the front end of the manipulator, thereby ensuring that the suction cup at the front end of the manipulator can smoothly grab the injection molded product. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0053] Figure 1 A schematic diagram of the overall structure of a manipulator control system for an injection molding machine provided by the present invention;

[0054] Figure 2 A schematic structural diagram of a manipulator control system for an injection molding machine provided by the present invention from another perspective;

[0055] Figure 3 A schematic structural diagram of a manipulator control system for an injection molding machine provided by the present invention when the claw rod is in an initial position;

[0056] Figure 4 A schematic diagram of the structure of a manipulator control system for an injection molding machine provided by the present invention when the claw rod is expanding outwards;

[0057] Figure 5 A schematic structural diagram of another viewing angle of a manipulator control system for an injection molding machine provided by the present invention when a claw rod is expanding outward;

[0058] Figure 6 A schematic diagram of the installation structure of a rotation control mechanism in a manipulator control system for an injection molding machine provided by the present invention;

[0059] Figure 7 A schematic diagram of the installation structure of a claw rod in a manipulator control system for an injection molding machine provided by the present invention;

[0060] Figure 8 A schematic diagram of the claw rod structure in a manipulator control system for an injection molding machine provided by the present invention;

[0061] Fig. 9 A schematic structural diagram of a claw rod control mechanism in a manipulator control system for an injection molding machine provided by the present invention;

[0062] Fig.10 A schematic diagram of controlling the gripping radius of a manipulator control system for an injection molding machine provided by the present invention.

[0063] Description of the drawings: 1. Base; 2. First arm; 3. Second arm; 4. Forearm; 50. Image acquisition module; 51. Data processing module; 52. Control module; 6. Injection molded product grabbing assembly; 60. Movable seat; 600. Assembly groove; 601. Annular groove; 602. Inner cavity; 61. Claw rod; 610. Mounting port; 611. Curved rod; 612. Rolling sleeve; 62. Suction cup; 620. Rotating connector with counterweight; 7. Rotation control mechanism; 70. Driving gear; 71. Fixed frame; 72. Motor; 73. Gear ring; 8. Claw rod control mechanism; 80. Cylinder; 81. Upper plate; 82. Lower plate; 83. Connecting rod; 84. Roller; 85. Groove; 9. Bearing. DETAILED DESCRIPTION

[0064] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, and use. It should be understood that in all of these figures, the same or similar reference numerals indicate the same or similar parts and features. The various drawings only schematically represent the concepts and principles of the embodiments of the present disclosure, and do not necessarily show the specific dimensions and proportions of the various embodiments of the present disclosure. Specific parts in specific drawings may be exaggerated to illustrate the relevant details or structures of the embodiments of the present disclosure.

[0065] Embodiment 1:

[0066] like Figures 1 to 4 As shown, this embodiment provides a technical solution: a manipulator control system for an injection molding machine, comprising a main body, an injection molded product grabbing assembly 6, a data acquisition module 50, a data processing module 51 and a control module, wherein the main body comprises a first arm 2, a second arm 3, a forearm 4 and a base 1, the first arm 2, the second arm 3, and the forearm 4 are sequentially connected to form a manipulator structure that can grab injection molded products within an operating radius, the base 1 is installed below the first arm 2 to support the manipulator structure, the injection molded product grabbing assembly 6 is rotatably connected to the front end position of the forearm 4 through a bearing 9 to grab injection molded products, the data acquisition module 50 is fixedly installed at the front end side position of the forearm 4 to collect image information of the injection molded products, and the data processing module 51 is arranged on the forearm 4, It is used to process the image information of the injection molded product, calculate the deviation value between the center of the injection molded product grasping component 6 and the center of gravity of the injection molded product, and determine whether the center of the injection molded product grasping component 6 corresponds to the center of gravity of the injection molded product based on the deviation value. If not, a first correction instruction is generated, and the optimal grasping radius of the injection molded product is calculated, and a second correction instruction is generated. The control module 52 is set on the forearm 4, including a first control submodule and a second control submodule. The first control submodule is used to generate a first control instruction according to the first correction instruction, and perform a first correction operation on the injection molded product grasping component 6 through the first control instruction. The second control submodule is used to generate a second control instruction according to the second correction instruction, and control the injection molded product grasping component 6 to perform a second correction operation through the second control instruction.

[0067] It should be noted that the image acquisition module 50 is a high-definition camera. This embodiment uses image processing technology to analyze the center of gravity position of the injection molded product based on the image of the injection molded product, and then controls the robot arm to move to the center of gravity position of the injection molded product for grasping, thereby ensuring the stability of the injection molded product during grasping, and obtaining the optimal grasping radius of the injection molded product through image analysis of the injection molded product. In summary, this embodiment can ensure that when the injection molded product is not in a unique position and posture, a suitable grasping position for the injection molded product can still be found, and the grasping is stable.

[0068] As a further description of the above technical solution: the method for calculating the deviation value between the geometric center of gravity position of the injection molded product and the center position of the injection molded product grabbing assembly 6 is as follows:

[0069] Take any point in the contour image of the injection molded product as the coordinate origin and any dimension as the unit distance to establish a plane XY rectangular coordinate system, and obtain the coordinates of each corner point in the contour image of the injection molded product, which are set as A1(x1,y1), A2(x2,y2), ... A n (x n ,y n ), then the coordinate calculation method of the geometric center of gravity O(x, y) of the contour image of the injection molded product is as follows:

[0070]

[0071] Among them, x and y are the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the injection molded product contour image, respectively. i ,y i are the coordinates of the i-th corner point of the injection molded product contour image, and n is the total number of edges of the injection molded product contour image;

[0072] Project the center position of the injection molded product grabbing assembly 6 onto the plane XY rectangular coordinate system to obtain the coordinates of the center position of the injection molded product grabbing assembly 6 in the plane XY rectangular coordinate system, which is recorded as O′(x′, y′);

[0073] The calculation method of the deviation value Y between the geometric center of gravity of the injection molded product and the center position of the injection molded product grabbing assembly 6 is as follows:

[0074]

[0075] Among them, Y is the deviation value between the geometric center of gravity of the injection molded product and the center position of the injection molded product grabbing assembly 6, x′ and y′ are respectively the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the center position of the injection molded product grabbing assembly 6, and x and y are respectively the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the injection molded product contour image.

[0076] As a further description of the above technical solution: the method for obtaining the coordinates of the center position of the injection molded product grabbing assembly 6 in the plane XY rectangular coordinate system is as follows:

[0077] The projection of the data acquisition module 50 is mapped to the plane XY rectangular coordinate system, and the coordinates of the data acquisition module 50 in the plane XY rectangular coordinate system are obtained, which are recorded as P(x0, y0). Then, the coordinate calculation method of the center position O′(x′, y′) of the injection molded product grabbing component 6 is as follows:

[0078]

[0079] Among them, x′ and y′ are respectively the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the center position of the injection molded product grasping component 6, x0 and y0 are respectively the X-axis coordinate and Y-axis coordinate of the data acquisition module 50, l1 and l2 are respectively the lateral distance and vertical distance between the data acquisition module 50 and the projection of the center position of the injection molded product grasping component 6.

[0080] As a further description of the above technical solution: the method for determining whether the center of the injection molded product grabbing assembly 6 corresponds to the center of gravity of the injection molded product is as follows:

[0081] The preset deviation threshold is Y1, then:

[0082] When Y≤Y1, it is determined that the center of the injection molded product grabbing assembly 6 corresponds to the center of gravity of the injection molded product, and the first correction instruction is not generated;

[0083] When Y>Y1, it is determined that the center of the injection molded product grabbing assembly 6 does not correspond to the center of gravity of the injection molded product, and a first correction instruction is generated.

[0084] As a further description of the above technical solution: the first control instruction includes a moving direction and a moving distance, wherein the moving direction is the direction from coordinate O to coordinate O′, and the moving distance is the deviation value Y.

[0085] As a further description of the above technical solution: the method for calculating the optimal gripping radius of the injection molded product is as follows:

[0086] The vertical distance from the geometric center of gravity of the contour image of the injection molded product to the nearest edge of the injection molded product is recorded as L, the safe distance that the injection molded product grasping component (6) needs to maintain with the edge of the injection molded product when grasping the injection molded product is recorded as L0, the grasping radius of the injection molded product grasping component (6) is recorded as R, and the maximum grasping radius of the injection molded product grasping component (6) is Rmax, then:

[0087] When L≥Rmax+L0, R=Rmax;

[0088] When L<Rmax+L0, R=L-L0.

[0089] Example 2

[0090] like Figures 1 to 9As shown, in order to realize the control of the manipulator control system, the injection molded product grabbing assembly 6 in this embodiment includes a movable seat 60, a claw rod 61, a rotation control mechanism 7 and a claw rod control mechanism 8, wherein the movable seat 60 adopts a cylindrical structure and is rotatably mounted on the forearm 4 through a bearing 9, and three assembly grooves 600 are opened in a circular array at the bottom of the movable seat 60, and there are three claw rods 61 in total, and a suction cup 62 is movably installed at the bottom, and the three claw rods 61 are correspondingly rotatably mounted in the assembly groove 600 at the bottom of the movable seat 60 through a rotating shaft; the rotation control mechanism 7 is arranged above the movable seat 60, and is used to control the rotation angle of the movable seat 60; the claw rod control mechanism 8 is arranged in the movable seat 60, and is used to control the opening radius of the claw rod 61.

[0091] It should be noted that the movable seat 60 is arranged at the front end of the forearm 4. During operation, the rotation angle is controlled by the rotation control mechanism 7 to achieve control and adjustment of the distribution angle of each claw rod 61. At the same time, the claw rod control mechanism 8 controls the expansion and contraction of the claw rod 61, so that the radius of the circle formed by the three suction cups 62 is consistent with the preset radius, thereby ensuring that the suction cup 62 on each claw rod 61 can fall on the predetermined position on the surface of the injection molded product.

[0092] As a further description of the above technical solution: in order to achieve the control and adjustment of the rotation angle of the movable seat 60, the rotation control mechanism 7 in this embodiment includes a fixed frame 71 and a driving gear 70, wherein the fixed frame 71 is fixedly installed on the side of the forearm 4, and a motor 72 is installed inside, and the driving gear 70 is installed on the output shaft of the motor 72. An annular groove 601 is opened circumferentially on the upper surface of the movable seat 60, and a gear ring 73 is embedded and installed circumferentially on the inner wall of the annular groove 601. The gear ring 73 is meshed with the driving gear 70, so that when the driving gear 70 rotates, the movable seat 60 can be driven to rotate through the gear ring 73. When the motor 72 is running, it can drive the driving gear 70 to rotate, and the gear ring 73 is meshed with the driving gear 70, so that the movable seat 60 can be driven to rotate as a whole, thereby achieving the control and adjustment of the rotation angle of the movable seat 60.

[0093] As a further description of the above technical solution: In order to control the expansion and contraction of the claw rod 61, the claw rod control mechanism 8 in this embodiment includes an upper plate body 81, a lower plate body 82 and a cylinder 80, wherein the center of the lower plate body 82 is fixedly connected to the upper plate body 81 through a connecting rod 83, and there is a gap between the upper plate body 81 and the lower plate body 82. The cylinder 80 is fixedly installed above the movable seat 60, and the piston rod of the cylinder 80 is fixedly connected to the upper plate body 81. The end of the claw rod 61 is connected to a curved rod 611, and the curved rod 611 is inserted into the gap between the upper plate body 81 and the lower plate body 82, so that when the upper plate body 81 and the lower plate body 82 move up and down, the curved rod 611 drives the bottom of the claw rod 61 to expand outward or retract inward, thereby realizing the expansion radius control and adjustment of the suction cup 62 on the claw rod 61.

[0094] Further, such as Figure 4 As shown, in order to ensure that the suction cup 62 can keep the suction surface of the suction cup 62 horizontal when the claw rod 61 is at different angles, in the present embodiment, a rotating connector 620 with a counterweight is installed above the suction cup 62, and a mounting opening 610 is opened at the bottom position of the claw rod 61. The rotating connector 620 with a counterweight is rotatably installed in the mounting opening 610 through a rotating shaft. Therefore, no matter what angle the claw rod 61 is at, under the action of the counterweight, the suction surface of the suction cup 62 can always remain horizontal, thereby ensuring that it is smoother when grasping the injection molded products.

[0095] Further, such as Figure 7 As shown, in order to ensure the mobility of the claw rod 61, in this embodiment, the interior of the movable seat 60 is hollowed out, and the claw rod control mechanism 8 is installed in the inner cavity 602 of the movable seat 60, and the inner side of the assembly groove 600 is connected with the inner cavity 602, so that the curved rod 611 can extend into the gap between the upper plate body 81 and the lower plate body 82 through the assembly groove 600. Therefore, when the upper plate body 81 and the lower plate body 82 move downward under the push of the cylinder 80, the end of the curved rod 611 moves downward, and at this time, the claw rod 61 rotates, and the bottom expands outward, and the three claw rods 61 are moved downward. The radius of the circle formed by the bottom suction cup 62 increases. When the cylinder 80 pushes to the maximum limit position, the three claw rods 61 are horizontal. At this time, the suction cup 62 reaches the maximum limit position. When the upper plate 81 and the lower plate 82 move upward under the push of the cylinder 80, the end of the curved rod 611 moves upward. At this time, the claw rod 61 rotates and the bottom is retracted inward. The radius of the circle formed by the bottom suction cup 62 of the three claw rods 61 decreases. When the cylinder 80 pushes to the minimum limit position, the three claw rods 61 are vertical. At this time, the suction cup 62 reaches the minimum limit position.

[0096] Specifically, Figure 8 and Fig. 9 As shown, in order to ensure that the claw rod 61 does not get stuck during the pushing process, in this embodiment, a rolling sleeve 612 is rotatably installed at the front end of the curved rod 611, and a groove 85 is opened at the position where the lower plate body 82 contacts the curved rod 611, and a roller shaft 84 is rotatably installed in the groove 85. Therefore, when the lower plate body 82 and the upper plate body 81 cooperate to push the curved rod 611 up and down, it is smoother, thereby avoiding the situation of getting stuck.

[0097] As a further description of the above technical solution, Fig.10 As shown: In order to realize the control of the grasping radius, the second control instruction includes the moving stroke of the cylinder 80, wherein the calculation method of the moving stroke of the cylinder 80 is as follows:

[0098] The grasping radius of the claw rod 61 is set to R, and the moving stroke of the cylinder 80 is set to P. The moving stroke of the cylinder 80 is P and is proportional to the grasping radius R of the claw rod 61. The larger the moving stroke of the cylinder 80, the larger the grasping radius R of the claw rod 61. The maximum allowable stroke of the cylinder 80 is set to Pmax, where:

[0099] When R=Rmax, the three claw rods 61 are horizontal, and the suction cups 62 on the three claw rods 61 reach the maximum radius. At this time, the cylinder 80 is pushed to the maximum limit position, that is, the moving stroke of the cylinder 80 is P=Pmax;

[0100] When R=L-L0, the angles of the three claw rods 61 are between 0°-90°, and the moving stroke of the cylinder 80 is P=kR, wherein k is the ratio of the moving stroke of the cylinder 80 to the horizontal distance from the center of the suction cup 62 at the bottom of the claw rod 61 to the center position of the injection molded product grasping assembly 6.

[0101] The exemplary implementation scheme of the present disclosure is described in detail above with reference to the preferred embodiments. However, it can be understood by those skilled in the art that, without departing from the concept of the present disclosure, various modifications and variations can be made to the above-mentioned specific embodiments, and various technical features and structures proposed in the present disclosure can be combined in various ways without exceeding the protection scope of the present disclosure, which is determined by the attached claims.

Claims

1. A manipulator control system for an injection molding machine, comprising: The main body is composed of a first large arm (2), a second large arm (3) and a forearm (4) which are movably connected in sequence, forming a manipulator structure capable of grasping injection molded products within an operating radius; An injection molded product grabbing assembly (6), which is rotatably connected to the front end of the forearm (4) via a bearing (9) and is used for grabbing the injection molded product; A data acquisition module (50) is fixedly mounted on the front side of the forearm (4) and is used to collect image information of the injection molded product; a data processing module (51), which is arranged on the forearm (4) and is used to process the image information of the injection molded product, calculate the deviation value between the center of the injection molded product grasping component (6) and the center of gravity of the injection molded product, determine whether the center of the injection molded product grasping component (6) corresponds to the center of gravity of the injection molded product based on the deviation value, and if not, generate a first correction instruction, calculate the optimal grasping radius of the injection molded product, and generate a second correction instruction; A control module (52) is arranged on the forearm (4), and comprises a first control submodule and a second control submodule, wherein the first control submodule is used to generate a first control instruction according to the first correction instruction, and perform a first correction operation on the injection molded product grasping component (6) through the first control instruction, and the second control submodule is used to generate a second control instruction according to the second correction instruction, and control the injection molded product grasping component (6) to perform a second correction operation through the second control instruction.

2. A robot control system for an injection molding machine according to claim 1, characterized in that: The method for calculating the deviation between the geometric center of gravity of the injection molded product and the center position of the injection molded product grabbing assembly (6) is as follows: Take any point in the contour image of the injection molded product as the coordinate origin and any dimension as the unit distance to establish a plane XY rectangular coordinate system, and obtain the coordinates of each corner point in the contour image of the injection molded product, which are set as A1(x1,y1), A2(x2,y2), ... A n (x n ,y n ), then the coordinate calculation method of the geometric center of gravity O(x, y) of the contour image of the injection molded product is as follows: Among them, x and y are the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the injection molded product contour image, respectively. i ,y i are the coordinates of the i-th corner point of the injection molded product contour image, and n is the total number of edges of the injection molded product contour image; Projecting the center position of the injection molded product grabbing assembly (6) onto the plane XY rectangular coordinate system, obtaining the coordinates of the center position of the injection molded product grabbing assembly (6) in the plane XY rectangular coordinate system, recorded as O′(x′, y′); The calculation method of the deviation value Y between the geometric center of gravity of the injection molded product and the center position of the injection molded product grabbing component (6) is as follows: Wherein, Y is the deviation value between the geometric center of gravity of the injection molded product and the center position of the injection molded product grasping component (6), x′ and y′ are respectively the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the center position of the injection molded product grasping component (6), and x and y are respectively the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the injection molded product contour image.

3. A robot control system for an injection molding machine according to claim 2, characterized in that: The method for obtaining the coordinates of the center position of the injection molded product grabbing assembly (6) in the plane XY rectangular coordinate system is as follows: The projection of the data acquisition module (50) is mapped to the plane XY rectangular coordinate system, and the coordinates of the data acquisition module (50) in the plane XY rectangular coordinate system are obtained, which are recorded as P (x0, y0). Then, the coordinate calculation method of the center position O'(x', y') of the injection molded product grasping component (6) is as follows: Among them, x′ and y′ are respectively the X-axis coordinate and Y-axis coordinate of the geometric center of gravity of the center position of the injection molded product grasping component (6), x0 and y0 are respectively the X-axis coordinate and Y-axis coordinate of the data acquisition module (50), and l1 and l2 are respectively the lateral distance and vertical distance between the projection of the center position of the data acquisition module (50) and the injection molded product grasping component (6).

4. A robot control system for an injection molding machine according to claim 3, characterized in that: The method for determining whether the center of the injection molded product grabbing assembly (6) corresponds to the center of gravity of the injection molded product is as follows: The preset deviation threshold is Y1, then: When Y≤Y1, it is determined that the center of the injection molded product grasping component (6) corresponds to the center of gravity of the injection molded product, and the first correction instruction is not generated; When Y>Y1, it is determined that the center of the injection molded product grasping component (6) does not correspond to the center of gravity of the injection molded product, and a first correction instruction is generated.

5. A robot control system for an injection molding machine according to claim 4, characterized in that: The first control instruction includes a moving direction and a moving distance, wherein the moving direction is a direction from coordinate O to coordinate O′, and the moving distance is a deviation value Y.

6. A robot control system for an injection molding machine according to claim 3, characterized in that: The method for calculating the optimal gripping radius of injection molded products is as follows: The vertical distance from the geometric center of gravity of the contour image of the injection molded product to the nearest edge of the injection molded product is recorded as L, the safe distance that the injection molded product grasping component (6) needs to maintain with the edge of the injection molded product when grasping the injection molded product is recorded as L0, the grasping radius of the injection molded product grasping component (6) is recorded as R, and the maximum grasping radius of the injection molded product grasping component (6) is Rmax, then: When L≥Rmax+L0, R=Rmax; When L<Rmax+L0, R=L-L0.

7. A robot control system for an injection molding machine according to claim 6, characterized in that: The injection molded product grabbing assembly (6) comprises: A movable seat (60) is of cylindrical structure and is rotatably mounted on the forearm (4) via a bearing (9). The bottom of the movable seat (60) is provided with three assembly grooves (600) in a circular array; There are three claw rods (61) in total, and a suction cup (62) is movably mounted at the bottom. The three claw rods (61) are correspondingly rotatably mounted in the assembly groove (600) at the bottom of the movable seat (60) via a rotating shaft; A rotation control mechanism (7), which is arranged above the movable seat (60) and is used to control the rotation angle of the movable seat (60); A claw rod control mechanism (8) is arranged in the movable seat (60) and is used to control the opening radius of the claw rod (61).

8. A robot control system for an injection molding machine according to claim 7, characterized in that: The rotation control mechanism (7) comprises: A fixing frame (71) which is fixedly mounted on the side of the forearm (4) and has a motor (72) installed inside; a driving gear (70) mounted on the output shaft of the motor (72); The upper surface of the movable seat (60) is provided with an annular groove (601) along the circumferential direction, and the inner wall of the annular groove (601) is embedded with a gear ring (73) along the circumferential direction. The gear ring (73) is meshed with the driving gear (70), so that when the driving gear (70) rotates, the movable seat (60) can be driven to rotate through the gear ring (73).

9. A robot control system for an injection molding machine according to claim 8, characterized in that: The claw lever control mechanism (8) comprises: Upper plate body (81); A lower plate body (82) is fixedly connected to the upper plate body (81) at its center via a connecting rod (83), and a gap is provided between the upper plate body (81) and the lower plate body (82); A cylinder (80) is fixedly mounted above the movable seat (60), and a piston rod of the cylinder (80) is fixedly connected to the upper plate (81); The end of the claw rod (61) is connected to a curved rod (611), and the curved rod (611) is inserted into the gap between the upper plate body (81) and the lower plate body (82), so that when the upper plate body (81) and the lower plate body (82) move up and down, the curved rod (611) drives the bottom of the claw rod (61) to expand outward or retract inward.

10. A robot control system for an injection molding machine according to claim 9, characterized in that: The second control instruction includes a movement stroke of the cylinder (80), wherein the movement stroke of the cylinder (80) is calculated as follows: The grasping radius of the claw rod (61) is set to R, the moving stroke of the cylinder (80) is set to P, and the maximum allowable stroke of the cylinder (80) is set to Pmax, wherein: When R=Rmax, the moving stroke of the cylinder (80) P=Pmax; when R=L-L0, the moving stroke of the cylinder (80) P=kR.

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