Multi-station self-adaptive material taking manipulator of injection molding machine

Abstract

The invention discloses a multi-station self-adaptive material taking manipulator of an injection molding machine. The multi-station self-adaptive material taking manipulator comprises a six-axis driving system and a material taking system, the material taking system comprises a flexible strip and a plurality of suction cups, the flexible strip is composed of a flexible outer wall and magnetorheological fluid and can be freely bent when not powered on, and the magnetorheological fluid is solidified to lock the shape after the flexible strip is powered on. Each suction cup is integrated with a spherical hinge structure, a magneto-rheological damper, a linear servo motor and a pressure sensor to form an active compliant unit. Rapid switching between flexible fitting and rigid supporting is achieved through magnetorheological fluid. The active compliance unit independently regulates and controls the posture of the sucker and accurately adapts to local features of the curved surface. And in combination with target function optimization and real-time pressure feedback, uniform distribution of grabbing force is ensured, workpiece damage is avoided, and the grabbing stability and the multi-station operation efficiency of the complex curved surface product are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to industrial robots, manipulator technology, and particularly relates to a multi-station adaptive material taking manipulator for injection molding machines. BACKGROUND

[0002] In the field of industrial automation, products after injection molding usually need to be taken and transported by a manipulator in multiple stations. Traditional manipulators generally use rigid clamps as taking devices, which are simple in structure and suitable for regular geometric workpieces. However, with the increasing demand for complex injection molded products (such as curved surfaces, thin-walled parts, etc.), the existing technology has the following defects:

[0003] Rigid clamps are difficult to adapt to the complex shape of curved surface injection molded products, especially when grabbing workpieces with large surface curvature changes, uneven clamping force distribution may cause local excessive force, resulting in product scratches, deformation or even damage.

[0004] Traditional manipulators rely on overall posture adjustment (such as six-axis linkage) to match the shape of the workpiece, but their response speed and flexibility are limited, making it difficult to compensate for small deviations in curved surfaces in real time.

[0005] Existing manipulators lack the ability to actively adjust the pressure distribution during the grabbing process, resulting in a decrease in grabbing stability when facing injection molded products of different sizes or materials, and easy slipping or clamping failure.

[0006] In addition, the taking system of traditional manipulators usually realizes grabbing through fixed suction cups or rigid clamps, but its structural rigidity is fixed and cannot dynamically adjust the suction cup posture or clamping force according to the curved surface shape of the workpiece, resulting in a low success rate of grabbing. Especially in a multi-station production scene, the manipulator needs to frequently switch grabbing, which is more troublesome. SUMMARY

[0007] Based on the above technical problems, the present application provides a multi-station adaptive material taking manipulator for injection molding machines.

[0008] The technical scheme of the present application is as follows:

[0009] A multi-station adaptive material taking manipulator for injection molding machines, comprising a six-axis driving system and a taking system, the six-axis driving system driving the taking system through multiple degrees of freedom,

[0010] characterized in that the taking system comprises a flexible strip, the bottom of the flexible strip is provided with a plurality of suction cups, and the flexible strip is composed of a flexible outer wall and a magnetorheological fluid,

[0011] wherein the plurality of suction cups are integrated with a spherical hinge structure, a magnetorheological damper, a linear servo motor and a pressure sensor at the bottom of the flexible strip to form an active compliant unit,

[0012] The specific steps are as follows:

[0013] Step 1: Target detection, identifying the gripping surface of the curved injection molded product;

[0014] Step 2: Calculate the initial gripping posture based on the detected curved injection molded product;

[0015] Step 3: Define the suction cup that is completely in contact with the gripping surface of the curved injection molded product as the core suction cup, and define the suction cup that is not completely in contact with the gripping surface of the curved injection molded product as the non-core suction cup.

[0016] Step 4: Adjust the posture of non-core suction cups to optimize gripping stability;

[0017] Step 5: Evaluate the gripping strength of all suction cups to determine the probability of successful gripping.

[0018] In this invention, the gripping surface of the curved injection molded product is scanned to obtain the gripping curved surface S.

[0019] Establish an objective function that includes the distance errors from all suction cups to the gripping surface S, as well as the angular errors between the suction cup axis direction and the normal vector of the gripping surface S.

[0020] The objective function is:

[0021]

[0022] Where the number of suction cups is N, and T represents the transformation matrix of multiple degrees of freedom of all suction cups;

[0023] Distance error term: p i This represents the local position coordinates of the i-th suction cup. This means that the local position coordinates of the suction cup are transformed into the global position coordinates of the suction cup using the transformation matrix T;

[0024] This represents the distance function from the point to the grasping surface S. Represents the weighting coefficient of the distance term;

[0025] Angle error term: m is the projection point q i The surface normal vector at point q i for The projection point on the grasping surface S is determined by the distance function. The nearest surface point obtained through calculation;

[0026] n i This represents the local axial direction of the i-th suction cup, which is multiplied by T to obtain the axial direction.

[0027] A measure of the goodness of fit, is the dot product of two vectors, equal to , The angle between two vectors.

[0028] In the present application, Ceres / PyTorch is used to build a residual, automatic differentiation is used to optimize the transformation matrix T, and the optimal transformation matrix T is output, and the initial grasping pose is output according to the optimal transformation matrix T.

[0029] In the present application, a pressure threshold Q th , for each suction cup, measure its pressure sensor reading Q i ,

[0030] If Q i is greater than Q th , it is determined to be a core suction cup; if Q i is less than Q th , it is determined to be a non-core suction cup.

[0031] In the present application, the linear servo motor adjusts the displacement until Q i approaches Q th The pressure threshold is set,

[0032] The calculation formula is as follows:

[0033]

[0034] The pressure deviation is represented by Q , K p , K i , K d , which represents an adjustment parameter, wherein the inclination attitude of the suction cup is adjusted through the spherical hinge structure during the adjustment of the linear servo motor.

[0035] In the present application, the material taking system comprises a mounting shaft, which is connected with the wrist arm,

[0036] The side of the mounting shaft is provided with an opening and closing motor, and the output shaft of the opening and closing motor is provided with a first transmission gear, which is meshed with a second transmission gear,

[0037] The second transmission gear is rotatably connected to the bottom of the mounting shaft, and the mounting shaft is fixedly connected with the retainer through the second transmission gear.

[0038] In the present application, the middle part of the retainer is fixedly connected with a worm, which is fixedly connected with the second transmission gear and rotates with the second transmission gear, and the two sides of the retainer are provided with turbines, which are meshed with the worm.

[0039] In the present application, the turbine is connected with one end of the first connecting rod, the other end of the first connecting rod is hinged with one end of the second connecting rod, and the other end of the second connecting rod away from the first connecting rod is provided with a clamping jaw,

[0040] The bottom of the retainer is connected with one end of the third connecting rod, and the other end of the third connecting rod is hinged in the middle of the second connecting rod.

[0041] In the present application, the flexible strip is arranged at the bottom of the third connecting rod.

[0042] In the present application, the six-axis driving system comprises a base, a circumferential rotation shaft, a first driving motor, a lower swing arm, a second driving motor, an upper swing arm, a third driving motor and a wrist arm.

[0043] The multi-station self-adaptive taking mechanical hand of the injection molding machine has the following beneficial effects:

[0044] The taking system integrates the flexible strip and the magneto-rheological fluid, controls the rheological properties of the magneto-rheological fluid through an external magnetic field, makes the flexible strip freely bend and fit the curved surface when not powered, and instantaneously locks the shape when powered to provide rigid support.

[0045] Each suction cup is equipped with a driven compliant unit, which can independently adjust the inclination angle and axial position of the suction cup, realize dynamic compensation for local features of the curved surface, and significantly improve the fitting accuracy.

[0046] The geometric data of the curved surface injection molded product is obtained through laser or image scanning, a target function optimization algorithm is combined, the optimal initial posture of the suction cup is calculated, and the number of core suction cups is maximized. Real-time monitoring of suction cup pressure sensor data dynamically adjusts the clamping force of non-core suction cups to ensure uniform pressure distribution during the grabbing process and avoid workpiece damage. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 It is a structural schematic diagram of the multi-station self-adaptive taking mechanical hand of the injection molding machine of the present application;

[0048] Figure 2 It is another angle structural schematic diagram of the multi-station self-adaptive taking mechanical hand of the injection molding machine of the present application;

[0049] Figure 3 It is a structural schematic diagram of the taking system of the present application;

[0050] Figure 4 It is another angle structural schematic diagram of the taking system of the present application;

[0051] Figure 5 It is a partial structural schematic diagram of the taking system of the present application;

[0052] Figure 6 It is a state schematic diagram of the taking system of the present application;

[0053] Figure 7 Another state diagram of the injection material taking system of the present application;

[0054] Figure 8 A flow chart of the injection material taking system of the present application;

[0055] Figure 9 A logic chart of the injection material taking system of the present application.

[0056] The reference signs are as follows: 10-six-axis driving system, 101-base, 102-circumferential rotation shaft, 103-first driving motor, 104-lower swing arm, 105-second driving motor, 106-upper swing arm, 107-third driving motor, 108-wrist arm, 20-material taking system, 201-mounting shaft, 201A-retaining frame, 202-opening and closing motor, 203-first transmission gear, 204-second transmission gear, 205-worm, 206-turbine, 207-first connecting rod, 208-second connecting rod, 209-third connecting rod, 210-clamping jaw, 211-flexible strip, 211A-flexible outer wall, 211B-magnetorheological fluid, 212-suction cup. DETAILED DESCRIPTION

[0057] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

[0058] Embodiment one

[0059] Referring to Figures 1-2 The embodiment provides an injection molding machine multi-station adaptive material taking manipulator, which comprises a six-axis driving system 10 and a material taking system 20.

[0060] The six-axis driving system 10 comprises a base 101, and a circumferential rotation shaft 102 is mounted above the base 101. A first driving motor 103 is arranged between the base 101 and the circumferential rotation shaft 102. The first driving motor 103 is used to drive the circumferential rotation shaft 102 to rotate along a J1 direction.

[0061] A lower swing arm 104 is arranged at an upper end of the circumferential rotation shaft 102, and a second driving motor 105 is mounted between the lower swing arm 104 and the circumferential rotation shaft 102. The second driving motor 105 is used to control the lower swing arm 104 to rotate along a J2 direction.

[0062] One end of the lower swing arm 104 is provided with an upper swing arm 106, and a third driving motor 107 is arranged between the lower swing arm 104 and the upper swing arm 106. The third driving motor 107 is used for controlling the rotation of the upper swing arm 106 in the J3 direction. The upper swing arm 106 is a telescopic shaft, which is used for controlling the extension and retraction of the upper swing arm 106 in the J4 direction. One end of the upper swing arm 106 is provided with a wrist arm 108, which rotates in the J5 direction. The wrist arm 108 away from one end of the upper swing arm 106 is provided with a material taking system 20, which can rotate in the J6 direction, and is used for taking the products molded by the injection molding machine and transporting the products to the designated position.

[0063] In the embodiment, the six-axis driving system 10 and the material taking system 20 work cooperatively to realize the automatic grabbing, posture adjustment and precise placement of the products molded by the injection molding machine.

[0064] The working principle is as follows: the first driving motor 103 drives the circumferential rotating shaft 102 to rotate around the vertical axis (J1 direction) of the base 101, so as to realize the overall rotation of the manipulator in the horizontal plane, adjust the horizontal orientation of the manipulator, and cover the multi-station material taking demand.

[0065] The second driving motor 105 drives the lower swing arm 104 to swing up and down around the hinge point (J2 direction) of the circumferential rotating shaft 102, controls the initial pitch angle of the manipulator in the vertical plane, and expands the working range.

[0066] The third driving motor 107 drives the upper swing arm 106 to swing around the hinge point (J3 direction) of the lower swing arm 104, further adjusts the stretching angle of the manipulator, and cooperates with the lower swing arm 104 to realize the precise positioning of the spatial position.

[0067] The upper swing arm 106 serves as a telescopic shaft and can be extended and retracted along its axis (J4 direction). A telescopic mechanism is integrated on the upper swing arm 106, which is generally a linear motor or a hydraulic cylinder. The effective length of the manipulator is directly changed to adapt to the material taking and placing requirements of different distances.

[0068] The wrist arm 108 rotates around the terminal axis (J5 direction) of the upper swing arm 106. The driving motor for controlling the wrist arm 108 is not labeled in the figure. The posture of the material taking system 20 is adjusted to ensure that the clamping angle matches the molded products of the injection molding machine.

[0069] The material taking system 20 rotates around the terminal axis (J6 direction) of the wrist arm 108 to complete the final posture adjustment of the products, so as to ensure that the products can be accurately placed in the designated position.

[0070] The six-axis driving system 10 is controlled through the linkage of the above six degrees of freedom. The large-scale spatial position of the manipulator is determined by J1-J3 axes, the distance is fine-tuned by J4 axis, and the posture of the end picking system 20 is adjusted by J5-J6 axes to ensure the clamping accuracy. After the picking system 20 clamps the injection molding product, the product is transported to the designated position through the reverse movement of each axis.

[0071] Referring to Figures 3-4 As shown in the figure, the picking system 20 includes a mounting shaft 201, which is connected with the wrist arm 108 through the mounting shaft 201. The side of the mounting shaft 201 is provided with an opening and closing motor 202. The output shaft of the opening and closing motor 202 is provided with a first transmission gear 203, and the first transmission gear 203 is engaged with a second transmission gear 204. The second transmission gear 204 is rotatably connected to the bottom of the mounting shaft 201, and the mounting shaft 201 penetrates the second transmission gear 204 and is fixedly connected with a retainer 201A.

[0072] The middle part of the retainer 201A is fixedly connected with a worm 205, and the worm 205 is fixedly connected with the second transmission gear 204 and rotates with the second transmission gear 204. The two sides of the retainer 201A are provided with a worm wheel 206, and the worm wheel 206 is engaged with the worm 205.

[0073] The worm wheel 206 is connected with one end of a first connecting rod 207, the other end of the first connecting rod 207 is hingedly connected with one end of a second connecting rod 208, and the end of the second connecting rod 208 away from the first connecting rod 207 is provided with a clamping jaw 210. The bottom of the retainer 201A is connected with one end of a third connecting rod 209, and the other end of the third connecting rod 209 is hingedly connected to the middle part of the second connecting rod 208.

[0074] In this embodiment, the picking system 20 controls the opening and closing action of the clamping jaw 210 by the opening and closing motor 202, thereby completing the grabbing and releasing of the material.

[0075] After the opening and closing motor 202 is started, the output shaft drives the first transmission gear 203 to rotate. The first transmission gear 203 is engaged with the second transmission gear 204 to transmit power to the second transmission gear 204. Since the second transmission gear 204 is rotatably connected to the bottom of the mounting shaft 201, the mounting shaft 201 itself does not rotate, but the rotation of the second transmission gear 204 will drive the worm 205 fixedly connected therewith to rotate synchronously.

[0076] The rotation of the worm 205 drives the rotation of the turbine 206 on both sides. The engagement of the turbine 206 with the worm 205 converts the rotary motion into lateral oscillation of the turbine 206, thereby driving the movement of the first connecting rod 207 connected with the turbine 206. The other end of the first connecting rod 207 is hinged to the second connecting rod 208, and the oscillation of the turbine 206 is transmitted to the second connecting rod 208 through the first connecting rod 207. At the same time, the third connecting rod 209 at the bottom of the holder 201A is hinged to the middle part of the second connecting rod 208, which plays a role in stabilizing and assisting transmission.

[0077] The movement of the second connecting rod 208 finally drives the gripper 210 to complete the opening and closing action. When the turbine 206 drives the first connecting rod 207 to contract inward, the second connecting rod 208 pushes the gripper 210 to close, realizing the clamping of the material; on the contrary, when the turbine 206 drives the first connecting rod 207 to expand outward, the gripper 210 opens, releasing the material.

[0078] However, the gripper 210 of the material taking system 20 still has deficiencies when grabbing the curved surface injection molded product. The main performance is that the rigid gripper 210 is difficult to fit the curved surface, and if the curved surface shape of the injection molded product is complex or the size changes greatly, the gripper may not be completely fitted, resulting in unstable grabbing or excessive local stress, causing product scratches or deformation. When grabbing the curved surface, uneven pressure distribution may cause surface indentation or damage of the product.

[0079] The injection molded product is low in rigidity, especially the thin-walled part. If the clamping force of the gripper is too large, it may cause product deformation or size out-of-tolerance. If the clamping force is insufficient, the curved surface product may slip during the handling process, affecting the stability of automatic production.

[0080] Embodiment Two

[0081] On the basis of the above-mentioned embodiments, the present embodiment is further disclosed based on the above-mentioned problems.

[0082] Referring again to Figures 3-9 As shown, the bottom of at least two third connecting rods 209 is provided with a flexible strip 211, and the bottom of the flexible strip 211 is provided with a plurality of suction cups 212. Among them, the flexible strip 211 is composed of a flexible outer wall 211A and a magnetorheological fluid 211B. Magnetorheological fluid (MR Fluid) has rheological properties that can quickly and reversibly change significantly under the action of an external magnetic field. After applying a magnetic field, the magnetorheological fluid can change from a liquid state to a semi-solid state, and quickly recover to a liquid state after removing the magnetic field. The performance change is completely reversible, without residual magnetization or permanent structural change.

[0083] The material taking system 20 is used to take the curved surface injection molded product. The gripper 210 is removed, and the curved surface injection molded product is taken by the plurality of suction cups 212 arranged at the bottom of the flexible strip 211. Before taking, the magnetorheological fluid 211B in the flexible strip 211 is not applied with a magnetic field, and can be bent at will.

[0084] Specifically, referring again to Figures 6-7 As shown in the figure, each suction cup 212 is integrated with a spherical hinge structure, a magnetorheological damper, a linear servo motor and a pressure sensor at the bottom of the flexible strip 211, to form an active compliant unit. The spherical hinge structure allows the suction cup 212 to tilt freely within a range of ±25°, to adapt to local curvature mutations. The magnetorheological damper changes the damping characteristics in real time by adjusting the magnetic field strength, to realize soft contact buffering and prevent hard collision damage to the workpiece. The linear servo motor cooperates with the pressure sensor to dynamically adjust the axial position of the suction cup according to the feedback of the pressure sensor, to ensure that each suction cup can be attached to the curved surface of the workpiece.

[0085] In this embodiment, referring to Figures 8-9 As shown in the figure, the specific steps of the multi-station adaptive material taking manipulator of the injection molding machine include:

[0086] Step 1: target detection, to identify the taking surface of the curved surface injection molded product;

[0087] Step 2: based on the detected curved surface injection molded product, to calculate an initial taking posture;

[0088] to calculate an initial taking posture, to attach to the taking surface of the curved surface injection molded product. Since the taking surface of the curved surface injection molded product is mostly a complex curved surface, not all suction cups can be completely attached to the taking surface of the curved surface injection molded product.

[0089] Step 3: define the suction cup that is completely attached to the taking surface of the curved surface injection molded product as a core suction cup, and define the suction cup that is not completely attached to the taking surface of the curved surface injection molded product as a non-core suction cup;

[0090] Step 4: adjust the posture of the non-core suction cup to optimize the taking stability;

[0091] Step 5: evaluate the taking strength of all suction cups, to judge the taking success probability.

[0092] In this embodiment, the taking surface of the curved surface injection molded product is scanned to obtain a curved surface S, wherein the scanning method adopts a laser scanning method or an image scanning method.

[0093] First, define an objective function that includes the distance error of all suction cups to the gripping surface S and the angular error between the suction cup axis direction and the normal vector of the gripping surface S. Adjust the overall error to a minimum to ensure that each suction cup fits the gripping surface S as accurately as possible. In other words, obtain as many core suction cups as possible.

[0094] The objective function is:

[0095]

[0096] The number of suction cups is N, and T represents the transformation matrix of all suction cups with multiple degrees of freedom.

[0097] Distance error term: p i This represents the local position coordinates of the i-th suction cup. This means that the local position coordinates of the suction cup are transformed into the global position coordinates of the suction cup through the transformation matrix T.

[0098] This represents the distance function from the point to the grasping surface S. This represents the weighting coefficient of the distance term.

[0099] Angle error term: m is the projection point q i The surface normal vector at point q i for The projection point on the grasping surface S is determined by the distance function. The nearest surface point obtained through calculation.

[0100] n i The direction of the local axis of the i-th suction cup is represented by T, and the axis direction is obtained by multiplying it by T.

[0101] The measure of the Jiadu error is the dot product of two vectors, equal to... , Let be the angle between two vectors; when The larger the angle, the greater the error.

[0102] In this embodiment, the distance error term is used to make the positions of multiple suction cups as close as possible to the gripping surface in the global coordinate system, minimizing the square of the distance error; the angle error term is used to make the axial directions of multiple suction cups as aligned as possible with the normal vector of the curved surface.

[0103] Furthermore, Ceres / PyTorch is used to construct residuals, and the transformation matrix T is automatically differentiated and optimized. This process is repeated 3-4 times until convergence, and the optimal transformation matrix T is output, thus ensuring that all suction cups simultaneously satisfy the following conditions: they are as close as possible to the workpiece surface, and the axial direction is aligned with the surface normal as much as possible.

[0104] According to the optimal transformation matrix T, the output initialization grasping posture is determined.

[0105] In this embodiment, the distinction between core and non-core suction cups is determined by the pressure value measured by the pressure sensor. A pressure sensor is integrated in each suction cup to monitor the contact pressure between the suction cup and the gripping surface in real time. When the suction cup is fully attached, the pressure value is high; when it is not fully attached due to a gap or partial contact, the pressure value is low.

[0106] Set a pressure threshold Q th For each suction cup, measure its pressure sensor reading Q i If Q i is greater than Q th , it is determined to be a core suction cup; if Q i is less than Q th , it is determined to be a non-core suction cup.

[0107] In this embodiment, the non-core suction cup posture is adjusted. The linear servo motor adjusts the displacement along the axial direction until Q i tends to Q th Set the pressure threshold.

[0108] The calculation formula is as follows:

[0109]

[0110] represents the pressure deviation, where , K p , K i , K d represents the adjustment parameter. During the adjustment of the linear servo motor, the inclination posture of the suction cup is adjusted through the spherical hinge structure.

[0111] Further, the magneto-rheological damper adjusts the damping coefficient according to the pressure Qi to prevent the workpiece from being pinched.

[0112] In this embodiment, the magneto-rheological fluid 211B is in a liquid state when not powered, and the flexible strip 211 is free to bend and attach to the curved surface; after power is turned on, the magneto-rheological fluid 211B instantly changes to a semi-solid state, locking the shape of the suction cup array and providing rigid support. Further, independent closed-loop control of the distributed active compliant unit solves the limitations of traditional mechanical hand overall posture adjustment.

[0113] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A multi-station adaptive material handling robot for injection molding machines, comprising a six-axis drive system (10) and a material handling system (20), wherein the six-axis drive system (10) drives the material handling system (20) via multiple degrees of freedom. Its features are, The material handling system (20) includes a flexible strip (211), with multiple suction cups (212) at the bottom of the flexible strip (211). The flexible strip (211) is composed of a flexible outer wall (211A) and a magnetorheological fluid (211B). Among them, multiple suction cups (212) integrate ball joint structures, magnetorheological dampers, linear servo motors, and pressure sensors at the bottom of the flexible strip (211), forming an active compliance unit. The specific steps are as follows: Step 1: Target detection, identifying the gripping surface of the curved injection molded product; Step 2: Calculate the initial gripping posture based on the detected curved injection molded product; Step 3: Define the suction cup that is completely in contact with the gripping surface of the curved injection molded product as the core suction cup, and define the suction cup that is not completely in contact with the gripping surface of the curved injection molded product as the non-core suction cup. Step 4: Adjust the posture of non-core suction cups to optimize gripping stability; Step 5: Evaluate the gripping strength of all suction cups to determine the probability of successful gripping.

2. The multi-station adaptive material handling robot for injection molding machines according to claim 1, characterized in that, Scan the gripping surface of the curved injection molded part to obtain the gripping surface S. Establish an objective function that includes the distance errors from all suction cups to the gripping surface S, as well as the angular errors between the suction cup axis direction and the normal vector of the gripping surface S. The objective function is: Where the number of suction cups is N, and T represents the transformation matrix of multiple degrees of freedom of all suction cups; Distance error term: p i This represents the local position coordinates of the i-th suction cup. This means that the local position coordinates of the suction cup are transformed into the global position coordinates of the suction cup using the transformation matrix T; This represents the distance function from the point to the grasping surface S. Represents the weighting coefficient of the distance term; Angle error term: m is the projection point q i The surface normal vector at point q i for The projection point on the grasping surface S is determined by the distance function. The nearest surface point obtained through calculation; n i This represents the local axial direction of the i-th suction cup, which is multiplied by T to obtain the axial direction. The measure of the Jiadu error is the dot product of two vectors, equal to... , Let be the angle between the two vectors.

3. The multi-station adaptive material handling robot for injection molding machines according to claim 2, characterized in that, The residual is constructed using Ceres / PyTorch, and the transformation matrix T is automatically differentiated and optimized. The optimal transformation matrix T is then output, and the initial grasping posture is output based on the optimal transformation matrix T.

4. The multi-station adaptive material handling robot for injection molding machines according to claim 2, characterized in that, Set a pressure threshold Q th For each suction cup, measure its pressure sensor reading Q. i , If Q i Greater than Q th If Q is the core suction cup, then it is determined to be the core suction cup; if Q i Less than Q th If so, it is determined to be a non-core suction cup.

5. The multi-station adaptive material handling robot for injection molding machines according to claim 4, characterized in that, The linear servo motor adjusts the displacement along the axial direction. Until Q i Approaching Q th Set pressure threshold, The calculation formula is as follows: Indicates pressure deviation, where K p K i K d This indicates the adjustment parameters, where the tilt angle of the suction cup is adjusted through a ball joint structure during the adjustment of the linear servo motor.

6. The multi-station adaptive material handling robot for injection molding machines according to claim 1, characterized in that, The material handling system (20) includes a mounting shaft (201) that engages with the wrist arm (108). An opening and closing motor (202) is provided on the side of the mounting shaft (201), and a first transmission gear (203) is provided on the output shaft of the opening and closing motor (202). The first transmission gear (203) meshes with a second transmission gear (204). The second transmission gear (204) is rotatably connected to the bottom of the mounting shaft (201), and the mounting shaft (201) passes through the second transmission gear (204) and is fixedly connected to the cage (201A).

7. The multi-station adaptive material handling robot for injection molding machines according to claim 6, characterized in that, A worm gear (205) is fixedly connected to the middle of the cage (201A). The worm gear (205) is fixedly connected to the second transmission gear (204) and rotates with the second transmission gear (204). A turbine (206) is provided on both sides of the cage (201A), and the turbine (206) meshes with the worm gear (205).

8. The multi-station adaptive material handling robot for injection molding machines according to claim 7, characterized in that, The turbine (206) is connected to one end of the first connecting rod (207), and the other end of the first connecting rod (207) is hinged to one end of the second connecting rod (208). A gripper (210) is installed on the end of the second connecting rod (208) away from the first connecting rod (207). The bottom of the retainer (201A) is connected to one end of the third link (209), and the other end of the third link (209) is hinged to the middle of the second link (208).

9. The multi-station adaptive material handling robot for injection molding machines according to claim 8, characterized in that, The flexible strip (211) is located at the bottom of the third link (209).

10. The multi-station adaptive material handling robot for injection molding machines according to claim 1, characterized in that, The six-axis drive system (10) includes a base (101), a circumferential rotation axis (102), a first drive motor (103), a lower swing arm (104), a second drive motor (105), an upper swing arm (106), a third drive motor (107), and a wrist arm (108).

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