Manipulator

Abstract

A robot hand (10) is provided with two or more fingers (20, 30), and is provided with a front-rear direction movement mechanism (60) that slidably moves at least one finger (30) in the front-rear direction of the robot hand (10) independently of the other one or more fingers (20).

Description

Technical Field

[0001] This invention relates to robotic arms. Background Technology

[0002] A gripper for holding an object has been proposed (see Patent Document 1). According to this gripper, an object can be held and transported.

[0003] Existing technical documents Patent documents Patent Document 1: Japanese Patent No. 6678648 Summary of the Invention

[0004] The problem that the invention aims to solve The goal is to develop a robotic arm capable of holding various objects.

[0005] Therefore, the object of the present invention is to provide a robotic arm capable of holding various objects.

[0006] Methods for solving problems To achieve the above objectives, one aspect of the present invention relates to a robotic hand having two or more fingers, characterized in that the robotic hand has a mechanism for independently sliding one or more of the two or more fingers in a front-back direction, wherein the front-back direction is any one of the following directions: (1) the direction connecting the tip of any one of the one or more fingers to the center of gravity of the root component of the robotic hand, the root component of the robotic hand being the part directly connected to a mechanical device composed of multiple components; (2) the direction along the normal vector of the connection surface directly connecting the mechanical device and the robotic hand; (3) the direction connecting the center of gravity of the component directly connected to the robotic hand among the multiple components constituting the mechanical device to the center of gravity of the robotic hand; and (4) the direction in which the diameter of the ellipsoid is longest when the shape of the robotic hand is approximated as an ellipsoid in the extended state of the one or more fingers.

[0007] Invention Effects According to the present invention, a robotic arm capable of holding various objects is provided. Attached Figure Description

[0008] Figure 1 This is a perspective view of the robotic arm in the implementation method.

[0009] Figure 2 Is to make Figure 1 The image shows a perspective view of one finger of the robotic arm moving backward. The other finger is hidden inside a cover.

[0010] Figure 3It involves moving one finger backward, using one finger to attract the upper surface of the object, and using... Figure 1 The image shown is a three-dimensional view of the robot arm holding the object in its position.

[0011] Figure 4 This involves using one finger to attract the top surface of an object, while simultaneously moving another finger backward and changing the angle of its tip to attract the side of the object. Figure 1 The image shown is a three-dimensional view of the robot arm holding the object in its position. Detailed Implementation

[0012] (Implementation Method) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, the embodiments described below represent specific examples of the present invention. The numerical values, shapes, materials, constituent elements, arrangement positions of constituent elements, connection methods, steps, and order of steps shown in the following embodiments are examples and are not intended to limit the present invention. Additionally, the figures are not necessarily strictly illustrative. In the figures, substantially identical structures are labeled with the same reference numerals, and sometimes repeated descriptions are omitted or simplified.

[0013] (3D view of the exterior) Figure 1 This is a perspective view of the robotic arm 10 according to the embodiment. The robotic arm 10 includes fingers 20 and 30, a root component 12, and a control unit 15. Figure 1 The figure shows the two fingers 20 and 30 of the robotic arm 10 in a relaxed, closed state. The mechanical device 50 on which the robotic arm 10 is mounted is also illustrated in this figure.

[0014] The robotic arm 10 is a robotic arm capable of grasping and holding objects. For example, the robotic arm 10 is mounted on a mechanical device 50. At this time, as needed, the two fingers 20 and 30 rotate around a first rotation axis A1, a second rotation axis A2, a third rotation axis A3, and a fourth rotation axis A4, respectively. They can rotate towards or away from one of the fingers 20 and 30, changing the positional relationship of each finger, and clamping an object between the fingers 20 and 30, thereby holding the object. Furthermore, the mechanism (finger drive unit) driving the first rotation axis A1, the second rotation axis A2, the third rotation axis A3, and the fourth rotation axis A4 is provided inside the fingers around each axis (not shown). Additionally, Figure 1 The shape of the joints of the fingers around each axis of rotation is a general representation and does not represent the strict physical structure.

[0015] Furthermore, a finger can also be defined as a rod-shaped portion with one or more rotating joints. Additionally, a rotating joint can be defined as two or more. Moreover, as a definition of a finger, even without a "rotating joint" as a definite hinge, a finger can be defined as "a rod-shaped portion having a mechanism that allows the finger to bend through overall deformation of the finger or a portion thereof." For example, it could also be a finger made of a flexible, easily deformable material, with a mechanism that allows the finger to bend through overall deformation of the finger.

[0016] Alternatively, the finger can be defined as a rod-shaped portion with some kind of drive mechanism. In this case, certain drive mechanisms may include not only drive mechanisms that function as rotating joints or the aforementioned "mechanisms that bend the entire finger or a portion thereof," but also drive mechanisms that extend or retract the finger. Furthermore, drive mechanisms that function as any deformable mechanism can also be included in any of the aforementioned drive mechanisms.

[0017] Furthermore, the robotic arm 10 involved in this invention does not necessarily need to have a looping function. Figure 1 The joints of each rotation axis of the finger part. Similarly, the robotic arm 10 involved in this invention does not necessarily need to have Figure 1 Control unit 15.

[0018] In addition, the robotic arm 10 is a robotic arm capable of adsorbing and holding objects. Similarly, for example, the robotic arm 10 is mounted on the mechanical device 50.

[0019] Additionally, the robotic arm 10 includes a forward / backward movement mechanism 60 that moves the finger section 30 backward (in the negative y direction) or forward (in the positive y direction) (see reference). Figure 2 Additionally, the y-axis represents the forward / backward direction as defined in this specification, the x-axis represents the direction orthogonal to the y-axis, and the z-axis represents the direction orthogonal to both the x-axis and y-axis.

[0020] The control unit 15 is the controller for controlling the robotic arm 10. It consists of a memory that stores programs and object information, a processor that executes programs, a camera that serves as an object detection unit for detecting the condition of the object being held, and is housed in the mechanical device 50, etc. Furthermore, in Figure 1 The control unit 15 is illustrated in the diagram.

[0021] Figure 2 This is a perspective view showing the state in which one finger (here, finger portion 30) of the robotic arm 10 according to the embodiment moves rearward (negative y direction) via the forward and backward movement mechanism 60 under the control of the control unit 15. Furthermore, in Figure 2 In the middle, the following was omitted. Figure 1 The diagram shows the mechanical device 50 and the control unit 15. The same applies to subsequent diagrams.

[0022] (Move forward or backward) Here, forward and backward movement can refer to changing the relative position of the finger or the tip of the finger with respect to the root component 12 of the robot or the component 51 on which the robot is installed in the forward and backward direction, or it can refer to making the finger slide forward, backward or outward in the forward and backward direction.

[0023] (Explanation of forward and backward directions) Alternatively, the forward / backward direction can be any of the following directions.

[0024] (1) The direction in which the front end of any one of the fingers is connected to the center of gravity of the root component 12 of the robot 10, wherein the root component 12 of the robot 10 is the part that is directly connected to the mechanical device 50 composed of multiple components. (2) Along the direction of the normal vector of the connection surface 11 that directly connects the mechanical device 50 and the robot arm 10; (3) The direction in which the center of gravity of the component 51, which is directly connected to the robot arm 10, in the components constituting the mechanical device 50 is connected to the center of gravity of the robot arm 10. (4) When the shape of the robot arm 10 is approximated as an ellipsoid in one or more finger extension states or in the maximum extension state, the direction of the longest diameter of the ellipsoid.

[0025] Furthermore, the forward and backward direction can also be referred to as the direction in which the root component 12 of the robot 10 extends. Moreover, the finger can move in the forward and backward direction as long as the movement vector of the finger has a component in the forward and backward direction (i.e., the y-axis direction). This includes not only movement along the forward and backward direction, but also movement in a direction with an angle of 90 degrees or less relative to the forward and backward direction.

[0026] Furthermore, the mechanical device 50 can also be a machine referred to as a robotic arm. Additionally, "direct connection" means a contact connection; "connection" includes not only direct connections but also indirect connections via other objects.

[0027] Additionally, the tip of the finger refers to the end point of the finger that is on the opposite side of the root of the robotic arm when the finger is captured into a rod shape.

[0028] In addition, Figure 1 In the context of approximating an ellipsoid as an ellipsoid when one or more fingers are extended or in their maximum extended state, the direction of the longest diameter of the ellipsoid refers to... Figure 1The y-axis direction is shown. In addition, approximating the robot with an ellipse can also mean approximating the coordinates of the robot's surface shape (for example, calculating the three-dimensional coordinates of the robot's surface at 1mm intervals, and the three-dimensional coordinates of all its points) as a three-dimensional ellipse (a long sphere or a flattened ellipse, like a rugby ball) by using the least squares method. In addition, (4) the long axis direction can also be set as the direction of three-dimensional extension when the robot is regarded as a long shape such as a rectangle or ellipse instead of a uniform shape such as a circle or square.

[0029] (The meaning of moving in the forward or backward direction) The forward and backward movement of the finger does not only refer to movement along any of the directions described in (1) to (4) (e.g., linear movement), but can also be a movement that includes a component of any of the directions described in (1) to (4). That is, for example, it can be a movement in an inclined direction that includes a component of movement in the left and right directions in addition to the forward and backward movement, or it can be a movement that includes a component of movement along any of the directions described in (1) to (4) and moves along a path that draws a curve. In addition, for it to be described as a forward and backward movement, the main component of the movement may also need to be any of the directions described in (1) to (4).

[0030] In addition, forward and backward movement can also be accompanied by changes in the angle of the fingers.

[0031] (Attraction port) Alternatively, at least one of the components of the robotic arm 10, either in the finger area or other parts, may have a vacuum (vacuum suction) suction port.

[0032] In this embodiment, suction ports 20a, 20b, 30a, and 30b are respectively provided on the finger portions 20 and 30. Therefore, under the control of the control unit 15, air can be drawn from the suction ports using a pump (not shown), etc., and the negative pressure can be used to suction and hold the object. Furthermore, as... Figure 1 As shown, the suction port can also be located on the inner side of the robotic arm 10, i.e., the side of the finger. Alternatively, the suction port can be located at the front end of the finger. Furthermore, the suction port can also be located on the outer side of the robotic arm 10, i.e., the side of the finger.

[0033] (The part refers to the area that is not the suction port itself) Furthermore, even when the finger has a suction port, the vacuum at the suction port can be avoided. Under the control of the control unit 15, the object can be held by simply using the physical clamping and pressing of one or more fingers (i.e., physical clamping and pressing between fingers or between fingers and other robotic arm parts). In this case, the fingers used for clamping and pressing must be those with suction ports, or they can be other different fingers.

[0034] (The movable part of the finger) Regarding the finger, as in this embodiment, the finger may have more than one drive mechanism. In addition, the drive mechanism of the finger may be configured not to overlap with the drive mechanism that moves the finger in the forward and backward direction (that is, these drive mechanisms are not common, and in the case of having a forward and backward movement mechanism 60, the finger needs to have another drive mechanism).

[0035] (The effect of moving the fingers backward to avoid the movement) The robotic arm 10 of this embodiment has (1) one or more fingers, or (2) two or more fingers, or (3) one or more of the two or more fingers that can move in the forward and backward direction.

[0036] Here, the phrase (3) above, "one or more of the two or more fingers can move in the front-back direction," means that, independently of one or more fingers, the other one or more fingers move in the front-back direction. That is, it means a different structure from one that allows all fingers to move "simultaneously" in the front-back direction. This means that the relative positional relationship between the position where one or more fingers can perform their function (e.g., the finger pressing position) and the position where one or more fingers can perform their function changes in the front-back direction.

[0037] This allows other fingers to retract from the movable range of a particular finger. Alternatively, when performing a task using more than one finger A, it allows one or more fingers B to retract to a position that will not adversely affect (obstruct) the task. This makes it easier to perform tasks using finger A, or to perform tasks that would be impossible to perform due to the physical interference of finger B if the fingers were not retracted.

[0038] For example, when using the suction port of one finger 20 to attract the top of an object, the other finger 30 is moved backward and retracted beforehand using the forward and backward movement mechanism 60. This allows the other finger 30 to use the suction port of one finger 20 without interfering with the object and to hold the object using the robotic arm 10 (see reference to moving the other finger 30 backward, using one finger 20 to attract the upper surface of the object 40, using...). Figure 1 The robotic arm 10 shown maintains the appearance of the object 40 in its current state. Figure 3 ).

[0039] Furthermore, this method of holding the object is also effective when there are constraints in the surrounding environment. For example, if there are other objects above the object, the object can be held in place by inserting one finger 20 into the gap between the object and the other object while retracting the other finger 30 backward.

[0040] (It can change the angle of the fingers. Other effects...) Alternatively, the angle of the tip 31 of the finger 30 can be changed. Under the control of the control unit 15, by changing the angle of the tip 31 of the finger 30 and making it follow the side of the object, not only the upper surface of the object can be attracted, but also the side surface of the object. That is, two or more suction ports can be used to evacuate vacuum along different orientations of the object. This also allows for the addition of two or more suction ports not only to multiple faces of a single object, but also to multiple faces of one or more objects of different shapes at different angles. In this case, one of the object information stored in the memory of the control unit 15, namely the shape information, or the surface shape information of the object detected by a camera or other object detection unit such as a camera included in the control unit 15, can be used. Under the control of the control unit 15, the angle of the tip 31 of the finger 30 can be changed along the side of the object. Similarly, the angle of the tip 21 of the finger 20 can also be changed.

[0041] This allows objects to be held more firmly (see reference). Figure 4 This appearance indicates that one finger 20 attracts the upper surface of the object 40, while the other finger 30 is moved backward and the angle of the front end 31 of the finger 30 is changed to attract the side of the object 40. Figure 1 The robotic arm 10 shown maintains the appearance of the object 40 in its current state.

[0042] in addition, Figure 4 To illustrate, in... Figure 4 In this process, the surfaces of the front end 21 and the front end 31 are aligned with the 90-degree angle of the object. However, it is not only the 90-degree angle of the surface that is considered, but also the relative angle and relative position of the front end 21 and the front end 31 are changed so that they are aligned with the surface or curved surface at any angle.

[0043] Furthermore, by enabling the finger 30 to move in the front-back direction, the distance and relative position relationship between the suction port of the finger 20 and the suction port of the finger 30 can be changed, thus enabling the holding of a wider variety of objects.

[0044] and, Figure 4 The suction port at the front end 31 can change its position in the vertical direction by changing the joint angles of the third rotation axis A3 and the fourth rotation axis A4, and can be held at a position along the surface of various objects by the suction port. This vertical adjustment is accompanied by a forward / backward offset, which is also effectively performed by the forward / backward movement mechanism 60. In addition, the change of position in the vertical direction is not limited to the change of the joint angles, but can also be based on the change of the sliding movement mechanism in the vertical direction.

[0045] (A sliding mechanism that can slide in the forward and backward direction) It should be noted that, as a specific example of the mechanism that moves the finger in the front-back direction, namely the front-back direction movement mechanism 60, it can be considered as a sliding mechanism composed of a sliding drive unit, in which its movement is a sliding movement. Alternatively, as another specific example, a mechanism that moves the finger in the front-back direction by rotational drive can also be considered. Furthermore, the front-back direction movement mechanism 60 can also be a movement mechanism other than these.

[0046] For example, it could also be a sliding mechanism that allows the finger or the tip of the finger to slide by flexing and extending the finger joints.

[0047] Alternatively, it can be a sliding mechanism that allows the finger or the tip of the finger to slide, based on a mechanism that extends or shortens the length of the finger itself.

[0048] Furthermore, the sliding mechanism can be a mechanism that has a driving mechanism and actively slides, or it can be a mechanism that slides by force from other sources. Moreover, in the case of a mechanism that slides by force from other sources, the sliding mechanism may also include a mechanism capable of fixing the sliding position.

[0049] (A description of the retreat of the fingertips and the space occupied by the fingertips) Furthermore, the forward / backward movement mechanism 60 can also be a mechanism capable of retracting the spatial region of the effect area of ​​one or more fingers that move in the forward / backward direction from the spatial region of the effect area of ​​one or more other fingers (i.e., preventing these two spatial regions from overlapping). Here, the spatial region of the effect area of ​​a finger can also be defined as the spatial region that a finger can occupy when the finger is moved using a movable part other than the forward / backward movement mechanism 60. In addition, in retracting the spatial region of the effect area of ​​a finger, in addition to the spatial region of the effect area of ​​each finger, a spatial region including its surrounding space (i.e., space as a margin) can also be considered. Here, the spatial region including its surrounding space can also be a spatial region that expands outward from the distance from the center of gravity of the spatial region of the effect area of ​​the finger to the boundary of the spatial region of the effect area of ​​the finger, or half of that distance.

[0050] Conversely, in the retreat of the spatial area of ​​the finger's effect range, the object can also be a spatial area that is reduced from the spatial area of ​​each finger's effect range. Furthermore, this reduced spatial area can also be a spatial area whose boundary has been moved inward from the boundary of the finger's effect range spatial area towards the center of gravity of that spatial area by a distance equal to one-third of the distance between the boundary and the center of gravity.

[0051] (Dimensions of the robotic arm) Additionally, if the thickness of more than one finger (in) Figure 1 In the middle, the thickness of each finger in the z direction when each finger is extended to its maximum extent in the y direction is small, and the width of the finger ( Figure 1 A narrow x-direction (in the image) is effective when there are stricter constraints on the surrounding environment. For example, a combination with a thickness of 70mm or less and a width of 120mm or less. Another example is a combination with a thickness of 50mm or less and a width of 100mm or less. Yet another example is a combination with a thickness of 40mm or less and a width of 70mm or less.

[0052] (Control example from the control department) As described above, the control unit 15 may also perform at least one of the following controls: (1) control to hold the object 40 by utilizing the vacuum at the suction ports 20a and 20b, etc. (see reference) Figure 3 , Figure 4 (2) Controlling the vacuuming of two or more suction ports 20a and 30a along different orientations of the object (this can also correspond to objects of different shapes (for example, see Figure 4 (3) Control of keeping the object 40 by means of physical clamping or pressing of one or more fingers 20 and 30 without using the vacuum at suction ports 20a and 20b, etc.

[0053] The robotic arm of the present invention has been described above based on embodiments and modifications, but the present invention is not limited to these embodiments and modifications. Various modifications conceived by those skilled in the art to these embodiments and modifications, as well as other methods of constructing embodiments and modifications by combining some of the constituent elements of the embodiments and modifications, are also included within the scope of the present invention, as long as they do not depart from the spirit of the invention.

[0054] [Industrial Applicability] The robotic arm involved in this invention can be used as a robotic arm capable of holding various objects.

[0055] Symbol Explanation 10. Robotic Arm 11. Connection surface between the robotic arm and the mechanical device 12. Root components of the robotic arm 15. Control Department 20, 30 fingertips Suction ports 20a, 20b, 30a, 30b 21 The front end of the finger 20 31 The front end of the finger 30 40 objects 50 Mechanical devices 51. Components of a mechanical device that are directly connected to a robotic arm. 60 Forward and backward moving mechanism A1 First rotation axis A2 Second Rotation Axis A3 Third Rotation Axis A4 Fourth Rotation Axis

Claims

1. A robot hand that is a robot hand having two or more fingers, has a mechanism that independently slides one or more of the two or more fingers in a front-rear direction from the other one or more fingers, the front-rear direction is any one of the following directions: (1) a direction that connects a front end of any one of the one or more fingers and a center of gravity of a root member of the robot hand, the root member being a site directly connected to a mechanical device composed of a plurality of components; (2) a direction along a normal vector of a connecting surface directly connecting the mechanical device and the robot hand; (3) a direction that connects a center of gravity of a component directly connected to the robot hand among the plurality of components constituting the mechanical device and a center of gravity of the robot hand; and (4) a direction in which a diameter of an ellipsoid approximating an outer shape of the robot hand in a state in which the one or more fingers are elongated is the longest.

2. The robot hand according to claim 1, wherein a control section that controls the robot hand is further provided, at least one of the one or more fingers has a suction port, the control section performs the following controls: (1) a control that holds an object by a vacuum at the suction port; and (2) a control that vacuums two or more of the suction ports along different surfaces of an object.

3. The robot hand according to claim 2, wherein the control section further performs the following control: (3) a control that holds an object by only physically pinching, pressing using the one or more fingers without using a vacuum at the suction port of the finger.

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