Mechanical gripper and method for picking up and placing objects using the same

Abstract

The present invention discloses a mechanical gripper, which comprises a mounting bracket and a plurality of suction parts arranged in an array on the mounting bracket for sucking objects, wherein the length of each suction part along its suction direction is adjustable. The mechanical gripper provided by the present invention has good universality. The present invention also discloses a method for picking up and placing an object using the mechanical gripper.

Description

Technical Field

[0001] The present invention relates to a plurality of industrial fields such as industrial production, logistics, and food processing, and in particular to a mechanical gripper and a method for picking up and placing an object using the mechanical gripper. Background Art

[0002] With the continuous improvement of industrial modernization, industrial production equipment is becoming more and more intelligent, gradually replacing traditional manual operations and improving operation standards and efficiency. Robotic arms are widely used in various industrial productions and can assist humans in various operations, such as sorting, placing, packaging, arranging and other process flows of objects. To a certain extent, it can improve production efficiency and reduce production operation costs.

[0003] The mechanical gripper is a very important part of the entire mechanical arm structure, and its mechanical structure affects the specific grasping effect. Existing mechanical grippers are diverse and of different specifications, so as to meet the grasping work of different products. The grasping methods are mainly vacuum suction and clamping. The suction gripper can effectively grasp block objects with flat surfaces and avoid damage by vacuum suction. However, the existing suction gripper has certain requirements for the flatness of the surface of the object. For objects with curved or irregular surfaces, the suction part does not match the surface of the workpiece, which is easy to leak and cannot form a stable air pressure difference, so it is impossible to achieve stable suction. In this case, the prior art will use a clamping gripper for grasping. Although the rigid clamping gripper can realize the grasping function, if its clamping part does not fit the outer surface of the object with irregular surface, it will lead to poor balance stability of grasping. However, the soft clamping gripper, due to its material characteristics, will cause vibrations due to the momentum applied to the clamping when clamping and moving heavier objects, which may cause the workpiece to fall. It can be seen that clamping grippers have certain safety hazards and also cause losses to enterprises. In various processing industries, the surfaces and shapes of various processed products are different and have certain irregularities. The various types of mechanical grippers currently available do not have ideal universality. During use, there may be problems such as frequent need to replace grippers or inability to perform precise grasping, which seriously affects production efficiency. Summary of the invention

[0004] The present invention provides a novel structure of a mechanical gripper, which comprises a mounting bracket and a plurality of suction parts for sucking objects, wherein the plurality of suction parts are arranged in an array on the mounting bracket, and the length of each suction part along its suction direction is adjustable.

[0005] In some embodiments, the operation of each suction portion is independently controlled.

[0006] In some embodiments, the plurality of suction portions are arranged on the same surface of the mounting bracket.

[0007] In some embodiments, the plurality of suction portions are detachably arranged on the mounting bracket.

[0008] The present invention also provides an innovative method for a mechanical gripper to pick up and place an object. The method includes a passive suction method and an active suction method. The passive suction method includes: the length of each suction part changes until it touches the surface of the object to be sucked; each suction part is vacuumed to suck the object to be sucked; the object to be sucked is moved to a predetermined position and then released. The active suction method includes: detecting the shape of the surface to be sucked of the object to be sucked; adjusting the length of each suction part of the mechanical gripper according to the detected shape so that the surface formed by the ends of multiple suction parts matches the shape of the surface to be sucked; moving the mechanical gripper until the ends of multiple suction parts are in contact with the surface to be sucked; sucking the object to be sucked by vacuuming the surface of the object to be sucked through multiple suction parts; and releasing the object to be sucked after moving the object to be sucked to a predetermined position.

[0009] In some embodiments, the method further comprises: displaying the process and result of the mechanical gripper operating the object to be sucked by means of visualization software.

[0010] The mechanical gripper provided by the present invention can self-adjust the length of the suction part according to the surface of the object so as to match the surface of the object and thus achieve stable suction, and has good universality. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to make the technical problems solved by the present invention, the technical means adopted and the technical effects achieved more clearly, the specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, it should be noted that the drawings described below are only drawings of exemplary embodiments of the present invention.

[0012] Figure 1 Schematic diagram of the mechanical gripper structure of an embodiment of the present invention.

[0013] Figure 2 It is a schematic diagram of the state of the mechanical gripper of an embodiment of the present invention when sucking an object.

[0014] Figure 3 It is a schematic structural diagram of the suction part of the mechanical gripper according to an embodiment of the present invention.

[0015] Figure 4 It is a schematic diagram of the working process of the mechanical gripper of an embodiment of the present invention when performing active suction.

[0016] Figure 5 It is a schematic diagram of the working process of the embodiment of the present invention when performing passive absorption. DETAILED DESCRIPTION

[0017] The exemplary embodiments of the present invention will now be described more fully with reference to the accompanying drawings. Although each exemplary embodiment can be implemented in a variety of specific ways, it should not be understood that the present invention is limited to the embodiments set forth herein. On the contrary, these exemplary embodiments are provided only to make the content of the present invention more complete and to facilitate the comprehensive communication of the inventive concept to those skilled in the art. Under the premise of being consistent with the technical concept of the present invention, the structure, performance, effect or other features described in a particular embodiment may be combined in any suitable manner into one or more other embodiments.

[0018] In the process of introducing specific embodiments, the detailed description of the structure, performance, effect or other characteristics is to enable those skilled in the art to fully understand the embodiments. However, it does not exclude that those skilled in the art can implement the present invention with a technical solution that does not contain the above-mentioned structure, performance, effect or other characteristics under certain circumstances.

[0019] The flowchart in the accompanying drawings is only an exemplary process demonstration, and does not mean that the solution of the present invention must include all the contents, operations and steps in the flowchart, nor does it mean that it must be executed in the order shown in the figure. For example, some operations / steps in the flowchart can be decomposed, some operations / steps can be combined or partially combined, etc. The execution order shown in the flowchart can be changed according to actual conditions without departing from the main purpose of the present invention.

[0020] The same reference numerals in the drawings represent the same or similar elements, components or parts, and thus the repeated description of the same or similar elements, components or parts may be omitted below. It should also be understood that although the first, second, third and other attributives indicating numbers may be used herein to describe various devices, components, elements or parts, these devices, components, elements or parts should not be limited by these attributives. In other words, these attributives are only used to distinguish one from another. For example, the first device may also be referred to as the second device, but it does not deviate from the essential technical solution of the present invention. In addition, the terms "and / or" and "and / or" refer to all combinations including any one or more of the listed items.

[0021] The present invention proposes a mechanical gripper structure (mechanical vacuum gripper) for industrial production and an innovative method for picking up and placing objects using the same. Objects with different surfaces and shapes can be grasped without replacing the end effector of the manipulator, thereby improving production efficiency and simplifying the production operation process.

[0022] See also Figure 1-3The mechanical gripper 10 of the embodiment of the present invention may include a mounting bracket 11 and a plurality of vacuum suction parts 12 arranged in an array on the mounting bracket 11 for sucking objects, and the length of each suction part 12 along its suction direction is adjustable.

[0023] like Figure 1-2 As shown, each suction portion 12 is a retractable strip suction cup structure. A plurality of strip suction cups 12 are on the same surface of the mounting bracket of the mechanical gripper (eg, Figure 1-2 The lower surface of the mounting bracket shown in the figure) is arranged in an array. A plurality of holes for installing the suction part can be set on the mounting bracket 11. The positions and sizes of the plurality of holes can be customized as needed. For example, the size is customized according to the size of the suction part to be arranged as needed. And its position can be customized as needed, for example, it can be arranged equidistantly in the row and column directions, or other arrangements can be adopted, and this document has no restrictions on this. Each suction part 12 is detachably arranged on the mounting bracket 11. The suction part 12 can be arranged in all the holes on the mounting bracket 11, or in only some of the holes, so that the arrangement of the plurality of suction parts 12 on the mounting bracket 11 can be adjusted as needed. For example, if the weight distribution of the object to be sucked is uneven, more suction parts can be arranged in the heavier part, and fewer suction parts can be arranged in the lighter part, and this document has no restrictions on this. The upper end of each suction part 12 can be connected to a vacuum pump 13, and the suction of objects of specific shapes and surfaces can be completed by the pressure difference generated by exhaustion. Reference Figure 2 According to the different shapes of the surface of the object to be grasped, each suction part 12 can change its length to achieve accurate suction and placement of objects of any shape.

[0024] The mechanical gripper of the embodiment of the present invention has two different operation modes, which can realize multi-purpose in an industrial assembly line. When the mechanical gripper is not equipped with an image recognition intelligent auxiliary system, a passive suction mode is adopted, and its operation process is: the mechanical gripper moves to the corresponding position (such as above the target object), the suction part will extend along its length direction, and stop when it touches the target object (determined by the built-in pressure sensor), and then the suction action is completed through the air pressure difference generated by the air pump, so as to realize its adaptability to objects of different shapes.

[0025] When the mechanical gripper is equipped with an image recognition intelligent system, an active suction method is used. The operation process is as follows: the mechanical gripper moves to the corresponding position (such as above the target object). After analyzing the appearance and surface characteristics of the target object, the length of each suction part of the mechanical gripper is adjusted to make it adsorb on the surface of the target object, forming a comprehensive coverage of the surface of the target object, and then the suction action is achieved through the pressure difference generated by the vacuum.

[0026] Each suction part is independently controlled in operation. That is, the suction part at the relevant position to perform the operation can be determined according to the needs. For example, if the target object is large in mass or volume, all suction parts can be used to operate together to suck the surface of the object at the same time, so that the mechanical gripper can suck the object with large mass or volume. On the other hand, when the mass or volume of the target object is relatively small, local operation can be adopted, and only the suction part at the corresponding position can be used to perform the suction action.

[0027] Based on the above two situations, when processing target objects of different shapes and sizes, the grasping performance of the mechanical gripper of the embodiment of the present invention will not be limited, ensuring that it can complete the task without replacing the parts of the suction part. It also solves the problem that when the surface of the target object is uneven or the shape is irregular, the suction part may not be able to completely fit the surface to be sucked of the target object, resulting in internal leakage. This structure can break through the limitations of the current industrial suction mechanical gripper, and accurately and stably grasp objects of any shape and surface, which is more convenient and efficient.

[0028] like Figure 3 As shown, each suction part 12 is mainly composed of two parts, the upper and lower parts. The upper part includes an air valve 121, a sensor 122, a control board 123, a motor 124, and a driving mechanism 125. The lower part includes a driven mechanism 126 and a terminal suction cup 127. Each suction part 12 can realize the up and down movement of its terminal suction cup 127 along the axis through the transmission action of the driven mechanism 126 under the control of the control board 123 and under the driving action of the driving mechanism 125. Under the control and driving action of the upper part, the terminal suction cup 127 can move up and down to reach a specified position on the surface. The two halves cooperate to form a suction cup structure with adjustable length.

[0029] The suction function of a single suction part is mainly achieved by vacuuming. Turn on the vacuum pump for suction, and the entire structure of the suction part is sealed and airtight. The resulting air pressure difference can firmly suck the surface of the object. Each suction part can fit the surface of the object by adjusting the position of the suction cup at its end (the position of the end suction cup 127 can be detected by the sensor 122). The control board 123 performs separate system control on each suction part in this process, and the driving mechanism 125 drives the driven mechanism 126 to move, thereby driving the end suction cup 127 to move up and down. When the air valve 121 is closed, the entire suction part is sealed and airtight. After the grasped object is grasped by the mechanical gripper and moved to the specified position, the vacuum pump is started to inflate, and the air valve 121 is opened. The air pressure inside the suction part rises and the object is placed.

[0030] Reference again Figure 2According to the surface and three-dimensional shape of the object, the suction cup array (adjustable spacing and arrangement) can achieve full coverage of the target object. When encountering objects with irregular shapes or surfaces, the suction cup array can adaptively form different end length combinations according to the specific conditions of the object surface. That is, the end suction cups of the suction part at the corresponding position can move different distances along their respective length directions. Finally, full coverage of the target object is achieved. In order to achieve accurate and efficient suction, transfer and placement of the target object.

[0031] Figure 4 This is a flow chart of an embodiment of the present invention when actively sucking. In this embodiment, the method of sucking an object using a mechanical gripper includes: 1) detecting the shape of the surface to be sucked of the object to be sucked; 2) determining the extension and retraction position of each suction part of the mechanical gripper according to the detected shape of the object, so that the end of each suction part fits with the surface of the object; 3) vacuuming through multiple suction parts to form suction force, sucking the object to be sucked; 4) moving the object to be sucked to a predetermined position and then releasing it.

[0032] refer to Figure 4 , the shape and surface of the target object to be sucked can be first identified by the corresponding recognition device, that is, visual shape detection is performed, and the shape of the target object is specifically analyzed after generating a three-dimensional cloud point map. After algorithm calculation, the required displacement of the end suction cup of each specific suction part is obtained, and each end suction cup is controlled to reach the specified position. The vacuum suction operation is started to suck the target object, and then the mechanical gripper drives the sucked object to the specified position and effectively places it.

[0033] akin, Figure 5 1 is a flow chart of an embodiment of the present invention when performing passive absorption. Figure 5 In this embodiment, the method of using a mechanical gripper to suck an object includes: 1) the mechanical gripper moves to a corresponding position (such as above a target object), 2) the suction portion extends along its length direction and stops when it touches the target object (determined by a built-in pressure sensor, 3) the suction operation is started to suck the target object, and 4) the mechanical gripper moves the object to a specified position. In addition, three-dimensional visualization software can be used to display the grabbing, movement process and results.

[0034] The present invention provides a new mechanical gripper structure and multifunctional gripping design for industrial production manipulators. That is, the present invention innovates the suction part of the suction-type mechanical gripper, so that a single suction part can operate independently, and move up and down along the axis driven by its micro motor to achieve the target position of the surface of the object, perform stable adsorption action, prevent problems such as suction cup leakage due to uneven surface of the object, and improve the strength and stability of gripping.

[0035] The present invention provides innovative operations when sucking objects of different shapes, and can use an intelligent recognition system to analyze and judge the surface and shape of the target object. According to different objects, the mechanical gripper makes corresponding adjustments, so that the gripper suction part covers the surface of the object, and then completes the grabbing. This process can grab objects flexibly and intelligently, has strong operability in actual production, and can greatly improve production efficiency.

[0036] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

[0037] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A mechanical gripper, characterized in that: The device comprises a mounting bracket and a plurality of suction parts for sucking objects. The plurality of suction parts are arranged on the mounting bracket in an array, and the length of each suction part along its suction direction is adjustable.

2. The mechanical gripper according to claim 1, characterized in that: The operation of each suction section is independently controlled.

3. The mechanical gripper according to claim 1, characterized in that: The plurality of suction portions are arranged on the same surface of the mounting bracket.

4. The mechanical gripper according to claim 1, characterized in that: The plurality of suction portions are detachably arranged on the mounting bracket.

5. A method for picking up and placing an object using the mechanical gripper of claim 1, characterized in that: The method includes a passive suction method and an active suction method, wherein the passive suction method includes: The length of each suction part changes until it touches the surface of the object to be sucked; Each suction part is vacuumed to suck the object to be sucked; After moving the object to be sucked to a predetermined position, releasing the object to be sucked; The active absorption method includes: Detecting the shape of the surface to be sucked of the object to be sucked; adjusting the length of each sucking part of the mechanical gripper according to the detected shape so that the surface formed by the ends of the multiple sucking parts is adapted to the shape of the surface to be sucked; The mechanical gripper is moved to the end of the plurality of suction parts so as to fit the surface to be sucked; the surface of the object to be sucked is sucked by the plurality of suction parts in a vacuum manner; After the object to be sucked is moved to a predetermined position, the object to be sucked is released.

6. The method according to claim 5, characterized in that Also includes: The process and result of the mechanical gripper operating the object to be sucked are displayed through visual software.

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