JP2021115658A - Cargo handling gear and article gripping mechanism - Google Patents

Abstract

To provide an article gripping mechanism that can appropriately grip articles regardless of presence or absence of a shape deformation thereof, even though the articles made of a wide variety of materials are mixed.SOLUTION: An article gripping mechanism is provided in a tip part of an arm of a robot arm that moves articles from an accumulation area to a desired area, and grips the articles releasably, which comprises an adsorption part, a lip deformation part and a base part. The adsorption part has a cylindrical body and a planar lip opened in a direction of an outer edge from a shaft core of the cylindrical body and provided at one end of the cylindrical body, which adsorbs and grips an article in a state where inner pressure of a system that is blocked from the outside by the cylindrical body, the lip and a surface on which the lip contacts the article is deteriorated. The lip deformation part transfers a state of the lip into a first state where external force is applied to the lip radially with respect to the shaft core to deform the lip and into a second state where the external force is not applied to the lip so as not to deform the lip. The base part is mounted on the tip part of the arm to support the adsorption part and the lip deformation part on the tip part of the arm.SELECTED DRAWING: Figure 3

Description

An embodiment of the present invention relates to a mechanism for gripping an article (article gripping mechanism) and a cargo handling device for handling an article gripped by using the article gripping mechanism.

In goods distribution centers and the like, various cargo handling devices for handling various goods such as unloaded luggage, parts, and products are used. In the cargo handling device, for example, articles accumulated in the accumulation area are picked by a manipulator (robot arm) and moved to a transfer device or the like. The transport device transports the articles to the next process such as sorting and assembling. The robot arm is provided with a tool (also called an end effector or the like) for handling an article at the tip of the arm. The tool has a gripping mechanism (article gripping mechanism) for gripping and picking an article from the accumulation area. As the article gripping mechanism, a suction mechanism for adsorbing an article with air is widely used.

Items that are handled at distribution centers (including items that are packed or packaged) are diversified, and their shapes, sizes, weights, and materials are various, and they are deformed according to the materials. The possibilities are not uniform either. In the suction mechanism, which is an example of the article gripping mechanism, the article is directly sucked by a suction member such as a suction pad, and the article is released by releasing the suction. For example, the suction pad is a superelastic body made of a rubber material or the like, and the lip portion at the tip is brought into close contact with the article to grip the article. When gripping the article, the shape of the lip portion is left to the rigidity of the article and is appropriately maintained by the rigidity of the adsorbed article.

Therefore, when the product is adsorbed on an article having a higher rigidity than the lip portion, for example, an article (box object) packed in a cardboard box or the like, the lip portion is maintained in an appropriate shape, and the box object can be appropriately gripped by the adsorption pad. .. On the other hand, when the soft material is adsorbed on an article having a lower rigidity than the lip part, for example, a soft material wrapped with a vinyl film or wrapping paper, the soft material is deformed by its own weight, so that the lip part cannot maintain an appropriate shape. Therefore, it is easy to be in a situation where such a flexible object cannot be properly gripped by the suction pad.

JP-A-2015-112664 Jikkenhei 01-84993 Japanese Patent No. 6373524

Therefore, even when articles of various materials such as flexible objects packed with vinyl film or the like and boxes packed with cardboard boxes or the like are mixed as articles to be gripped, regardless of whether or not the form is deformed. , An article gripping mechanism capable of appropriately gripping these articles and a cargo handling device including the same.

The article gripping mechanism of the embodiment is provided at the arm tip portion of the robot arm for moving the article from the accumulation region to a desired region, and is a mechanism for gripping the article in a releasable manner, and is a suction portion, a lip deforming portion, and a base. It has a part. The suction portion has a tubular body and a planar lip that opens from the axis of the tubular body toward the outer edge and is provided at one end of the tubular body. The article is sucked and gripped in a state where the internal pressure of the system closed from the outside is lowered. The lip deforming portion transitions the state of the lip into a first state in which an external force is applied to the lip radially with respect to the axis to deform the lip and a second state in which the lip is not deformed without applying an external force to the lip. .. The base portion is attached to the tip portion of the arm, and supports the suction portion and the lip deformed portion on the tip portion of the arm.

The schematic diagram which shows the cargo handling apparatus provided with the article gripping mechanism of embodiment from above in the vertical direction. The block diagram of the cargo handling apparatus of embodiment. The figure which shows schematic the mode of the article gripping mechanism in the initial state in the cargo handling apparatus of embodiment. FIG. 5 is a diagram schematically showing an embodiment of an article gripping mechanism in a state in which a close contact portion (lip) is deformed by a lip deforming portion in the cargo handling device of the embodiment. FIG. 5 is a diagram schematically showing a configuration of a suction portion (suction pad) viewed from the tip side in the article gripping mechanism of the cargo handling device of the embodiment. The figure which shows the schematic structure of the pressing member (pressing bar) from the horizontal direction in the article gripping mechanism of the cargo handling device of embodiment. The figure which shows the schematic structure of the pressing member (pressing bar) from above in the vertical direction in the article gripping mechanism of the cargo handling device of embodiment. The figure which shows the schematic structure of the lip deformed part from the upper side in the vertical direction in the article gripping mechanism of the cargo handling device of embodiment. The control flow diagram of the article movement processing in the cargo handling apparatus of embodiment. In the article gripping mechanism of the cargo handling device of the embodiment, it is a figure which shows typically an example of the gripping mode when the selected article is a flexible object, (a) is from the horizontal direction, (b) is upward in the vertical direction. The figure which shows each gripping mode from. In the article gripping mechanism of the cargo handling device of the embodiment, the figure schematically shows an example of the gripping mode when the selected article is a box (the surface to be adsorbed is a flat surface), and FIG. (B) is a diagram showing a gripping mode from above in the vertical direction. In the article gripping mechanism of the cargo handling device of the embodiment, the figure schematically shows an example of the gripping mode when the selected article is a box (the surface to be adsorbed is a curved surface), and FIG. (B) is a diagram showing a gripping mode from above in the vertical direction. FIG. 5 is a diagram schematically showing an aspect of an article gripping mechanism in a state where a close contact portion (lip) is deformed by a lip deformed portion in a cargo handling device of a modified example of the embodiment.

Hereinafter, the cargo handling device and the article gripping mechanism according to the embodiment will be described with reference to FIGS. 1 to 13. The cargo handling device is a device that handles goods, and is one of the devices that constitute a distribution system that operates in, for example, a distribution center. Goods are tangible items that can be handled, such as parcels, parcels, packages including mail, various parts and products. The article includes not only the article itself, but also a tangible object in which the article is packed or wrapped. It is assumed that the mode (shape, size, weight, material, etc.) of the article is not uniform but various, but it may be uniform. The article includes both an article whose form is not freely deformed (hereinafter referred to as a box) and an article whose form is freely deformed (hereinafter referred to as a flexible object) as its material (including the packed state and the packaged state). Is done. Cargo handling includes various operations on moving goods such as unloading and loading.

The box does not deform due to its own weight during cargo handling work and maintains a certain shape. For example, it is a box-shaped object housed in a packing container such as corrugated cardboard with flat surfaces. The packaging container is not limited to a hexahedron, but also includes a polyhedron in which specific corners and sides of the hexahedron are flat. On the other hand, the flexible object deforms due to its own weight during cargo handling work and changes its form. For example, it is a relatively lightweight flat object such as clothing and foods wrapped in vinyl film or wrapping paper, but the present invention is not limited thereto.

1 and 2 schematically show the cargo handling device 1 of the present embodiment. FIG. 1 is a diagram schematically showing a cargo handling device 1 from above in the vertical direction. The vertical direction is orthogonal to the horizontal plane (for example, the floor surface of the building of the distribution center). FIG. 2 is a block diagram of the cargo handling device 1.

As shown in FIGS. 1 and 2, the cargo handling device 1 includes a detection device 2, an article moving device 3, and a control device 4.
The detection device 2 performs various detections necessary for controlling the movement of the article 5 from the accumulation area 11 to the desired area (hereinafter referred to as the movement destination area) 12, and obtains the detection result (acquired data) of the control device 4. Give to. The accumulation area is, for example, an area in which various unloaded articles are temporarily accumulated before being transported to the next step. The articles 5 in the accumulation area may be arranged in an orderly manner, may be piled up in bulk, or may be placed individually one by one. The destination area is, for example, an area for transporting an article to a sorting process, an assembly process, or the like. The accumulation area 11 and the destination area 12 are, for example, a box or cage for accommodating an article 5, a conveyor such as a belt conveyor or a roller conveyor, a transport device such as a trolley, or a work table for sorting or assembling. FIG. 1 shows an example in which a workbench is applied as the integration area 11 and a belt conveyor cell is applied as the movement destination area 12.

In the present embodiment, the detection device 2 has a detection unit 21 and an analysis unit 22.
The detection unit 21 detects the accumulation mode of the article group 5s in the accumulation region 11. The article group 5s is an aggregate of articles 5 accumulated in the accumulation area 11, but is defined including the case where only one article 5 is accumulated. When there is only one article 5 accumulated, for example, there is only one article 5 accumulated from the beginning, and a plurality of articles 5 are accumulated one by one from the accumulation area 11 to the destination area 12 This includes the case where the articles are sequentially moved to and finally become one (only one article 5 that has not been moved remains).

The accumulation mode of the article group 5s is, for example, an aspect such as a position, a contour, a size, an orientation, a posture, an overlap, a boundary, and a material of each of the accumulated articles 5. In this embodiment, an RGB camera is applied as the detection unit 21 in order to detect these integration modes. The RGB camera captures a color image of the article group 5s accumulated in the integration region 11. Therefore, the RGB camera is arranged at a predetermined position where the integrated region 11 is within the angle of view and can be focused. For example, the RGB camera can be arranged at an arbitrary position such as a frame for partitioning the accumulation area 11, a ceiling or a wall surface of a distribution center building, an article moving device 3, or a base portion 61 of an article gripping mechanism 6 described later. As a result, the RGB camera is able to color-blindly capture the accumulation mode of the article group 5s and clearly grasp the accumulation mode of the article group 5s. However, a 3D camera, a plurality of 2D cameras, a spectroscopic camera, or the like may be applied to the detection unit 21 in place of or in addition to the RGB camera. The detection unit 21 gives the analysis unit 22 the data of the image captured by the RGB camera as an example of the detection result.

The analysis unit 22 analyzes the detection result (image data as an example) of the detection unit 21 and analyzes the accumulation mode of the article group 5s. Specifically, information for analyzing image data showing the accumulation mode of the article group 5s and specifying the position, contour, size, orientation, posture, overlap, boundary, material, etc. of each of the accumulated articles 5. (Analysis data) is output.

As a method of analyzing image data, for example, values such as intensity, hue, saturation, and lightness of each RGB color are threshold-determined, and the contour and boundary of the article 5 are determined based on the shape formed by the boundary line (edge). The method etc. can be applied. As a method for separating the article 5 (identifying the selected article described later) in the article group 5s, for example, when the edge forms a closed curve, a method in which the inside of the closed curve is one article 5 or the like can be applied. Further, as an analysis (determination) method of the shape, position, and posture of the separated article 5, a method of collating the image in the closed curve with the article data in the database (master data) can be applied. Further, for example, when a 3D camera is applied as the detection unit 21, it is possible to determine the division of the article 5 in the article group 5s and the shape, position, and posture of the separated article 5 by analyzing the acquired point cloud data. It is possible.

The analysis unit 22 adds the output analysis data to the control device 4. The control device 4 selects the article 5 to be gripped from the article group 5s based on the analysis data of the accumulation mode of the article group 5s given (details will be described later). The analysis unit 22 may be included in one of the components of the control device 4 instead of the detection device 2.

The article moving device 3 is a device for moving the article 5 in the cargo handling device 1, picking the article 5 from the accumulation area 11 and moving the article 5 to the moving destination area 12. As shown in FIG. 1, the article moving device 3 includes a base portion 31, an arm portion 32, and a tool (also referred to as an end effector) 33, and the arm portion 32 is displaced with respect to the base portion 31. It is a so-called picking robot (hereinafter referred to as a robot arm 3). However, the article moving device 3 can be a SCARA robot (horizontal articulated robot), an XYZ stage, or the like, and the article moving device 3 having a movable range corresponding to the moving range of the article 5 may be applied.

The base portion 31 is positioned and fixed to the floor surface of the building of the distribution center, for example. However, the base portion 31 may be movable with respect to the floor surface without being positioned and fixed in this way. For example, the base portion 31 may be slidably supported along a guide rail laid on the floor surface, or mounted on a linear stage or a self-propelled carriage. This makes it possible to move the robot arm 3 with respect to the floor surface as needed.

The arm portion 32 extends from the base end to the tip, which is a connection portion with the base portion 31, by being connected by a plurality of joint portions. The arm portion 32 is subdivided into a plurality of parts by the joint portion, and each portion rotates around a predetermined axis at the joint portion. As a result, the arm portion 32 is in a desired posture with respect to the base portion 31, and is freely displaced (moved) within a predetermined range. The predetermined range (that is, the movable range) includes the accumulation area 11 of the article 5 and the destination area 12 to which the article 5 is moved. Therefore, by rotating each portion of the arm portion 32 around an axis at an arbitrary angular velocity or angular acceleration, the arm portion 32 can be displaced with respect to the integrated region 11 and the destination region 12. The number of joints and shafts may be arbitrarily set according to the operating accuracy and movable range required for the arm 32.

The tool 33 is detachably attached to the tip of the arm portion 32 (arm tip portion 32a), and includes an article gripping mechanism 6 that grips the article 5 so as to be releasable. Gripping is defined as a concept that includes all aspects of holding the article 5, such as suction and pinching. As an example in the present embodiment, the tool 33 sucks and releases the article 5 by air. As a result, the tool 33 attracts the article 5 from the accumulation region 11 by the article gripping mechanism 6 and releases the adsorbed article 5 in the movement destination region 12, thereby moving the article 5 from the accumulation region 11 to the movement destination region 12. It is possible to make it.

3 and 4 show a schematic configuration of the article gripping mechanism 6 from the horizontal direction (as an example, a direction parallel to the floor surface of the building of the distribution center). FIG. 3 is a diagram schematically showing an aspect of the article gripping mechanism 6 in the initial state described later. FIG. 4 is a diagram schematically showing an aspect of the article gripping mechanism 6 in a state where the lip 62b is deformed by the lip deforming portion 7 described later.

As shown in FIGS. 2 to 4, the article gripping mechanism 6 includes a base portion 61, a suction portion 62, a vacuum generator 63, a compressor 64, a solenoid valve 65, a pressure sensor 66, a first pipe 67, and a second pipe. It is configured to include 68, a joint 69, and the like. As a result, the robot arm 3 grips the article 5 from the accumulation region 11 by the article gripping mechanism 6 (specifically, sucks the article 5 by the suction portion 62), and releases the gripped article 5 in the movement destination region 12, thereby causing the article. 5 can be moved from the accumulation region 11 to the destination region 12.

The base portion 61 is attached to the arm tip portion 32a and supports each component of the article gripping mechanism 6. The form of the base portion 61 is not particularly limited as long as it does not interfere with the operation of the arm portion 32. Although FIGS. 3 and 4 show an example in which the base portion 61 is a box body having an open portion in part, the base portion 61 may be a frame body or the like. The base portion 61 may be made of metal having rigidity capable of supporting each component of the article gripping mechanism 6, but may be made of resin or the like as long as it has the necessary rigidity.

The suction portion (hereinafter referred to as a suction pad) 62 is made of a material that can be easily deformed, for example, a rubber material having a low hardness such as silicone or polyvinyl chloride. As an example, the rigidity of the suction pad 62 may be lower than that of the box and higher than that of the flexible material, but may be lower than that of the flexible material. The suction pad 62 has a tubular body 62a and a lip 62b, and the lip 62b sucks and grips the article 5. In the state where the article 5 is gripped, the internal pressure of the system (in short, the inside of the suction pad 62) closed from the outside by the tubular body 62a, the lip 62b, and the surface to be attracted to the article 5 is reduced. The surface to be adsorbed on the article 5 is the surface on which the lip 62b comes into contact with the article 5 when the article 5 is adsorbed on the adsorption pad 62.

The tubular body 62a is continuously formed with a predetermined length from one end (base end) 621 to the other end (tip) 622 in the extension direction (hereinafter referred to as the shaft core direction) of the shaft core A. In the present embodiment, as an example, a part of the tubular body 62a is a transformation portion 62c whose form can be freely changed. However, the tubular body 62a may be a transformation portion as a whole, or the transformation portion may be omitted.

The transformation portion 62c has a bellows structure from the base end 621 side of the tubular body 62a toward the tip end 622 side. As a result, the transformation portion 62c can be expanded and contracted in the axial direction, and can be bent and deformed along the valley of the bellows. The number of ridges and valleys of the bellows of the transformation portion 62c is not particularly limited, and is arbitrarily set according to, for example, the mode of the article 5 (size, shape, weight, material (including packing state and packing state), etc.). NS. Further, the shape of the transformation portion 62c is optimized according to the mode of the article 5, such as thickening (spreading toward the end), straight line (straight shape), and tapering.

The lip 62b is a tip portion of the suction pad 62 and is continuously provided on the transformation portion 62c. The lip 62b opens from the axis A toward the outer edge of the tubular body 62a, and extends in a planar shape at the tip 622 of the tubular body 62a (transformation portion 62c). FIG. 5 schematically shows the configuration of the suction pad 62 as viewed from the tip side. As shown in FIG. 5, the shape of the lip 62b when viewed from the tip side has a planar shape defined by an outer circle C1 and an inner circle C2 concentric with the axis A. At the center of the lip 62b, an opening 62d communicating with the inside of the cylinder of the cylinder 62a (transformation portion 62c) penetrates in the axial direction.

The vacuum generator 63 creates a negative pressure or opens the inside of the suction pad 62 (inside the cylinder of the transformation portion 62c) to the atmosphere (vacuum breakage). The vacuum generator 63 is, for example, an ejector, and generates a vacuum by supplying compressed air. Instead of this, the vacuum generator 63 may be a vacuum pump, a vacuum blower, or the like. The compressor 64 supplies compressed air to the vacuum generator 63. The compressor 64 is connected to the vacuum generator 63 via the first pipe 67 and the solenoid valve 65. The first pipe 67 is relayed by a joint 69 to connect the compressor 64 and the solenoid valve 65. The joint 69 relays the first pipe 67 between the outside and the inside of the base portion 61. The vacuum generator 63 is connected to the suction pad 62 via the second pipe 68. The first pipe 67 and the second pipe 68 are, for example, a rubber tube, a resin or metal pipe member, and the like. These piping routes are not particularly limited and can be arbitrarily piped.

The solenoid valve 65 switches between a supply state and a supply stop state of compressed air from the compressor 64 to the vacuum generator 63 by opening and closing. Specifically, when the solenoid valve 65 is open, compressed air is supplied from the compressor 64 to the vacuum generator 63 via the first pipe 67. As a result, the vacuum generator 63 evacuates the suction pad 62 via the second pipe 68, and the inside of the second pipe 68 and the suction pad 62 becomes negative pressure. On the other hand, when the solenoid valve 65 is closed, the supply of compressed air from the compressor 64 to the vacuum generator 63 is stopped. As a result, the vacuum generator 63 vacuum-breaks the suction pad 62, and the inside of the second pipe 68 and the suction pad 62 is opened to the atmosphere. In the present embodiment, as an example, the control device 4 controls the opening / closing of the solenoid valve 65. The solenoid valve 65 may be configured as a part of the piping structure of the robot arm 3 instead of the article gripping mechanism 6.

The pressure sensor 66 is connected to the second pipe 68, measures the pressure (internal pressure) inside the suction pad 62, and outputs the measured value. The measured value (internal pressure value) of the internal pressure of the suction pad 62 is an index indicating whether or not the lip 62b is properly in close contact with the article 5 when the article 5 is adsorbed by the suction pad 62. The internal pressure value output by the pressure sensor 66 is given to the control device 4. The control device 4 determines whether or not the lip 62b is properly in close contact with the article 5 based on the internal pressure value of the applied suction pad 62 (details will be described later).

In addition to or in addition to the pressure sensor 66, a flow rate sensor for measuring the flow rate of compressed air in the second pipe 68 may be connected to the second pipe 68. By using the flow rate sensor, the responsiveness of the measurement can be improved as compared with the pressure sensor 66. Alternatively or in addition to these, the article gripping mechanism 6 may include an optical sensor capable of measuring the distance to the object. For example, an optical sensor may be arranged on the base portion 61 in the direction in which the suction pad 62 attracts the article 5 (axis direction), and the distance from the article 5 in this direction may be measured by the optical sensor. Thereby, it is possible to supplement the determination of whether or not the lip 62b is properly in close contact with the article 5 based on the distance from the article 5 measured by the optical sensor. For example, if the measured separation distance is equal to or less than the length in the axial direction of the suction pad 62 having a normal shape in which the transformation portion 62c does not shrink, it can be determined that the lip 62b is properly in close contact with the article 5. Further, the vacuum generator 63, the solenoid valve 65, and the pressure sensor 66 do not have to be housed in the base portion 61. For example, the outer side of the base portion 61, the base portion 31 of the robot arm 3, and the guard fence surrounding the robot arm 3. It may be arranged in such as.

In addition to the above-described constituent members, the article gripping mechanism 6 further includes a lip deforming portion 7 as an operating mechanism for deforming the lip 62b as needed, as shown in FIGS. 2 to 4.
The lip deforming portion 7 applies an external force to the lip 62b to deform the lip 62b. The configuration of the lip deforming portion 7 is not particularly limited, but in the present embodiment, as an example, a link mechanism having a pressing member 71, a connecting member 72, a supporting member 73, and a driving member 74 is used.

The pressing member 71 is displaced with respect to the base portion 61 to press the lip 62b and deform it. The pressing member 71 is displaced between a first position for transitioning the lip 62b to the first state and a second position for transitioning the lip 62b to the second state.

The first state is a state in which an external force is applied to the lip 62b to deform the lip 62b (the state shown in FIG. 4), and the second state is a state in which no external force is applied to the lip 62b and the lip 62b is not deformed (in FIG. 3). The state shown). In the present embodiment, the lip 62b is pressed and deformed in the first state, and the lip 62b is returned to the normal shape before deformation without being pressed in the second state (in other words, the normal shape is maintained as it is). ). That is, the first position corresponds to the position where the pressing member 71 presses the lip 62b (hereinafter referred to as the pressing position), and the second position is retracted from the lip 62b without the pressing member 71 pressing the lip 62b. Corresponds to the position to be evacuated (hereinafter referred to as the retracted position).

At the pressing position, the transformation portion 62c of the suction pad 62 adsorbed on the article 5 is in a contracted state (hereinafter referred to as a contracted state). The contracted state is a state in which the transformed portion 62c of the suction pad 62 adsorbed on the article 5 cannot be further contracted, and is the most contracted state, but also includes a state in which the deformed portion 62c is contracted to about the same degree. At the pressing position, the pressing member 71 presses the lip 62b of the suction pad 62 in which the transformation portion 62c is in the contracted state. On the other hand, in the retracted position, the transformation portion 62c is in either a contracted state or a state in which it is most extended (hereinafter referred to as an extended state). The extended state is a state in which the inside of the suction pad 62 is opened to the atmosphere (vacuum fracture), and the transformation portion 62c does not shrink and has a normal shape. At the retracted position, the pressing member 71 does not press the lip 62b regardless of whether the transformation portion 62c is in the contracted state or the extended state. However, in the state where the lip 62b is adsorbed on the article 5 (the contracted state of the transformation portion 62c), the lip 62b abuts on the surface to be adsorbed on the adsorbed article 5 to support the article 5. The surface to be adsorbed is a surface on the article 5 that is adsorbed on the lip 62b and has a target gripping position described later.

FIG. 6 shows a schematic configuration of the pressing member 71 from the horizontal direction (as an example, a direction parallel to the floor surface of the building of the distribution center). As shown in FIG. 6, the pressing member 71 is connected to the driving member 74 by the connecting member 72, and is supported by the base portion 61 by the supporting member 73. In the examples shown in FIGS. 3, 4 and 6, the pressing member 71 is a rod-shaped member bent in the middle (hereinafter referred to as a pressing bar 71). The pressing bar 71 is composed of a base portion 711, an acting portion 712, and a contact portion 713 in succession from the base end to the tip end.

The base portion 711 is continuous from the connecting position with the connecting member 72 to the supporting position with the supporting member 73. A through hole 714 through which the connecting shaft 721, which will be described later, is inserted is formed at the connecting position of the base portion 711 with the connecting member 72. The acting portion 712 is bent with respect to the base portion 711 and continuously extends from the support position on the support member 73. A supported body (hereinafter referred to as a cam follower) 715 supported by the support member 73 stands up at a support position on the support member 73, that is, a continuous position between the base portion 711 and the action portion 712. In the examples shown in FIGS. 3, 4 and 6, the cam follower 715 stands up in a columnar shape from the continuous position of the base portion 711 and the working portion 712.

The angle between the base portion 711 and the acting portion 712 (angle θ1 shown in FIG. 4, hereinafter referred to as bending angle) is such that the contact direction of the contact portion 713 with the lip 62b approaches the shaft core A. It is set in a predetermined range that tilts with respect to. That is, the acting portion 712 extends from the support position (continuous position with the base portion 711) so that the direction in which the contact portion 713 presses the lip 62b approaches the axis A. As a result, the angle at which the contact portion 713 comes into contact with the lip 62b (hereinafter referred to as the contact angle), that is, the inclination angle of the contact portion 713 with respect to the horizontal plane at the time of contact (for example, the floor surface of the building of the distribution center) ( The angle θ2) shown in FIG. 4 is smaller than 90 °. In other words, the bending angle θ1 and the contact angle θ2 may be set so that the contact angle θ2 is an acute angle.

The abutting portion 713 is provided at the tip (extended end) of the acting portion 712, is a portion that abuts on the lip 62b, and is a portion that abuts on the lip 62b and deforms the lip 62b. The contact portion 713 has a shape and a material that easily deforms the lip 62b when it comes into contact with the lip 62b. Therefore, it is preferable that the contact portion 713 has a shape that is closer to line contact with the lip 62b. However, shapes that form surface contact or point contact (saw blade-shaped multiple vertices or single apex) are not particularly excluded. In the present embodiment, as an example, the contact portion 713 is formed in a substantially trapezoidal columnar shape in which the tip portion (the end on the contact side with the lip 62b) is tapered as shown in FIG. The tip may have a predetermined curvature (about 0.3). Further, the contact portion 713 may be formed of a resin or the like having a rigidity higher than that of the lip 62b so as not to damage the lip 62b at the time of contact. The base portion 711, the acting portion 712, and the cam follower 715 may be formed of the same material as the contact portion 713, or may be formed of different materials.

The contact portion 713 has a shape longitudinally longitudinally in the radial direction of the lip 62b, and abuts with the lip 62b radially with respect to the shaft core A. The contact length (L71 shown in FIG. 4) is set to an appropriate dimension within the width of the lip 62b (W62 shown in FIG. 5). The contact length L71 of the contact portion 713 is the length at which the contact portion 713 comes into contact with the lip 62b along the radial direction of the lip 62b. The width W62 of the lip 62b is the radial length of the lip 62b, and is the diameter difference between the outer circle C1 and the inner circle C2 concentric with the axis A in the lip 62b. As an example, the contact length L71 of the contact portion 713 is about half the size of the width W62 of the lip 62b. In the state of being in contact with the lip 62b, one end of the contact portion 713 in the contact length L71 direction is substantially overlapped with the outer circle C1 of the lip 62b.

With such a configuration, when the pressing bar 71 is displaced to the first position (pressing position) as shown in FIG. 4, the contact portion 713 abuts on the lip 62b and presses the lip 62b radially. .. As a result, the lip 62b is deformed so that the pressed portion by the contact portion 713 sinks more than the other portions and the entire lip 62b undulates in the circumferential direction. As a result, for example, when the suction pad 62 is sucked on the flexible object, the lip 62b is deformed into a shape that grips the flexible object, so that the suction posture can be stabilized. Further, since the load applied to the lip 62b is distributed almost evenly, it is possible to improve the durability of the lip 62b.

On the other hand, when the pressing bar 71 is displaced to the second position (retracted position) as shown in FIG. 3, the contact portion 713 is separated from the lip 62b without pressing the lip 62b. As a result, the lip 62b returns from the state of being deformed so as to be wavy as a whole to the normal shape before the deformation (in another way, the normal shape is maintained). Further, in the retracted position, the contact portion 713 supports the article 5 by contacting the contact portion with the surface to be adsorbed by the lip 62b so as to be substantially flush with each other (state shown in FIG. 11 to be described later). ..

The connecting member 72 has a connecting shaft 721 and a bearing 722 that supports the connecting shaft 721. The connecting shaft 721 is a shaft body that is inserted through the through hole 714 of the base portion 711 and rotatably connects the pressing bar 71 to the bearing 722 around the connecting shaft 721. In the examples shown in FIGS. 3, 4 and 6, one connecting shaft 721 connects two pressing bars 71 to the bearing 722. As shown in FIG. 7, each of the connected pressing bars 71 is formed with a meshing portion 716 having alternating steps on the base portion 711. FIG. 7 is a diagram showing a schematic configuration of the pressing bar 71 from above in the vertical direction. As a result, the two pressing bars 71 are arranged substantially point-symmetrically with a point on the axis A as a point of symmetry, and are rotatably connected to each other around a common connecting shaft 721 in opposite directions. Therefore, these pressing bars 71 can press and deform the lips 62b at positions symmetrical with respect to the axis A. However, the meshing portion 716 can be omitted. The bearing 722 supports the connecting shaft 721 and is attached to the drive member 74 (specifically, the piston rod 742 described later) in a state of supporting the connecting shaft 721. As a result, the bearing 722 is displaced with respect to the base portion 61 by the drive member 74 together with the connecting shaft 721 (details will be described later).

The support member 73 supports the pressing bar 71 on the base portion 61 at a predetermined position so as to be displaceable between the first position (pressing position) and the second position (retracting position). The predetermined position is not limited, but in the examples shown in FIGS. 3 and 4, it is a continuous position between the base portion 711 and the acting portion 712, in other words, a bending position of the pressing bar 71. The support member 73 has a support 731 provided on the base portion 61 and a guide 732 formed on the support 731 to move the cam follower 715.

The support body 731 is provided to define the support position of the pressing bar 71 with respect to the base portion 61. The guide 732 is a groove formed in the support 731 (hereinafter referred to as a cam groove 732), and when the pressing bar 71 presses and deforms the lip 62b, the starting point and the ending point of the displacement of the pressing bar 71 with respect to the base portion 61 To specify. As an example, the starting point is the retracted position and the ending point is the pressing position, but the reverse is also possible. That is, the cam groove 732 moves the pressing bar 71 between the position corresponding to the first state and the position corresponding to the second position described above.

The cam groove 732 extends linearly from the starting point to the ending point of the displacement of the pressing bar 71, and when the pressing bar 71 is displaced, the cam follower 715 is moved (sliding) while being in sliding contact with the cam follower 715. The path of the cam groove 732 from the start point to the end point of the displacement of the pressing bar 71 is provided along the direction intersecting the shaft core A (in the example shown in FIGS. 3 and 4, the direction approaching the shaft core A). In the example shown in FIGS. 3 and 4, the cam groove 732 has an oval contour shape having curved portions at both ends 733 and 734 in the extension direction. The curvature of the curved portion is slightly smaller than the curvature around the column of the columnar cam follower 715. The distance between the linear contour portions connecting the curved portions is slightly larger than the diameter of the columnar cam follower 715.

One end 733 of the cam groove 732 defines a displacement starting point (retract position) of the pressing bar 71 with respect to the base portion 61. FIG. 3 shows a state in which the pressing bar 71 is located at the retracted position. In this state, the cam follower 715 contacts one end 733 of the cam groove 732. On the other hand, the other end 734 of the cam groove 732 defines the displacement end point (pressing position) of the pressing bar 71 with respect to the base portion 61. FIG. 4 shows a state in which the pressing bar 71 is positioned at the pressing position. In this state, the cam follower 715 contacts the other end 734 of the cam groove 732.

The driving member 74 applies power to the pressing bar 71, the connecting member 72, and the supporting member 73 to displace the pressing bar 71 between the first position (pressing position) and the second position (retracting position). The drive member 74 may have an arbitrary configuration, but as an example, it is a linear actuator. In the examples shown in FIGS. 3, 4 and 6, the air cylinder is applied as the drive member 74. As an air supply source, the compressor 64 is shared with the vacuum generator 63. However, the lip deforming portion 7 may be provided with an air supply source of a system different from that of the vacuum generator 63 exclusively for the air cylinder. Further, the drive member 74 may be an electric means such as a hydraulic cylinder or other linear actuator, for example, an electromagnetic solenoid. Alternatively, it may be a means for converting a rotational driving means such as a DC motor into a linear motion by an arbitrary mechanism, or a means for displacing the position of the contact portion 713 in an arc trajectory.

The drive member (hereinafter referred to as an air cylinder) 74 has a cylinder body 741 and a piston rod 742 that moves forward and backward with respect to the cylinder body 741. The cylinder body 741 includes a cylinder (air chamber), a piston, an air supply / exhaust pipe, and the like (all not shown), and is supported by the base portion 61 so that the advancing / retreating direction of the piston rod 742 coincides with the axial core direction. .. The piston rod 742 moves back and forth in the cylinder by the air supplied to and discharged from the cylinder of the cylinder body 741. A bearing 722 is attached to the piston rod 742. As a result, the piston rod 742 moves back and forth with respect to the cylinder body 741, and the bearing 722 moves back and forth in the axial direction (up and down movement in the examples shown in FIGS. 3, 4, and 6). As a result, the lip deforming portion 7 (pressing bar 71, connecting member 72, supporting member 73), which is a link mechanism, is operated, and the pressing bar 71 is displaced between the retracted position and the pressing position.

In the example shown in FIG. 3, the piston rod 742 is located at the initial movement position with respect to the cylinder body 741, and in this case, the pressing bar 71 is positioned at the retracted position. In the example shown in FIG. 4, the piston rod 742 moves upward from the initial movement position to the final movement position with respect to the cylinder body 741, in other words, the piston rod 742 is pulled into the cylinder body 741, and the pressing bar 71 is pressed. Positioned. Another way of thinking is that the piston rod 742 moves downward from the final movement position to the initial movement position with respect to the cylinder body 741, in other words, the piston rod 742 is pushed out from the cylinder body 741, which is shown in FIG. As in the example, the pressing bar 71 is positioned at the retracted position. For example, on the contrary, when the piston rod 742 is pulled into the cylinder body 741, the pressing bar 71 is positioned at the retracted position, and when it is pushed out from the cylinder body 741, the pressing bar 71 is positioned at the pressing position. May be good. In this case, for example, the other end 734 of the cam groove 732 may define the displacement start point (retract position) of the pressing bar 71, and one end 733 may define the displacement end point (pressing position) of the pressing bar 71.

In this embodiment, as shown in FIG. 8, a link mechanism is configured in which four pressing bars 71, two connecting shafts 721, one bearing 722, and four support members 73 are operated by one air cylinder 74. There is. FIG. 8 is a diagram showing a schematic configuration of the lip deformed portion 7 from above in the vertical direction. In such a link mechanism, the pressing bar 71a and the pressing bar 71c are connected by a connecting shaft 721a, and the pressing bar 71b and the pressing bar 71d are connected by a connecting shaft 721b. These pressing bars 71a to 71d are attached to the piston rod 742 via the bearing 722. In the state of being attached to the piston rod 742, the pressing bar 71a is supported by the supporting member 73a, the pressing bar 71b is supported by the supporting member 73b, the pressing bar 71c is supported by the supporting member 73c, and the pressing bar 71d is supported by the supporting member 73d, respectively. Has been done. The four pressing bars 71a to 71d are arranged at intervals of 90 ° in the circumferential direction about the axis A. By arranging in this way, the four pressing bars 71a to 71d are displaced from the four sides centered on the axis A with respect to the base portion 61, respectively. As a result, the lip 62b can be pressed and deformed at four points by the four pressing bars 71a to 71d. As a result, the lip 62b is deformed so that the entire lip 62b undulates substantially evenly in the circumferential direction.

As shown in FIG. 2, the control device 4 controls the operations of the detection device 2, the robot arm 3, and the article gripping mechanism 6 to manage the operation of the cargo handling device 1. The control device 4 includes a CPU, a memory, a storage device (nonvolatile memory), an input / output circuit, a timer, and the like, and executes a predetermined arithmetic process. For example, the control device 4 reads various data by the input / output circuit, performs arithmetic processing by the CPU using the program read from the storage device into the memory, and based on the processing result, the detection device 2, the robot arm 3, and the article gripping mechanism 6 Controls the operation of. The control device 4 is connected to the detection device 2, the robot arm 3, and the article gripping mechanism 6 by wire or wirelessly, and sends and receives various data, calculation results, and the like to and from these in operation control.

The control device 4 has a planning unit 41 and a control unit 42.
The planning unit 41 controls the operation of the detection device 2 to detect the accumulation mode of the article 5, reads the analysis data of the detection result by the input / output circuit, and calculates the calculation by the CPU using the program read from the memory. Based on the result, the operation plan of the robot arm 3 is formulated. Further, the planning unit 41 operates the article gripping mechanism 6 (vacuum generator 63, compressor 64, solenoid valve 65, pressure sensor 66, lip deforming unit 7 (driving member 74)) based on the operation plan of the robot arm 3. Develop a plan. The planning unit 41 assigns the formulated information (operation command) of these operation plans to the control unit 42.

The control unit 42 controls the operation of the robot arm 3 and the article gripping mechanism 6 based on the given operation command. Specifically, the control unit 42 operates the robot arm 3 based on the operation command of the robot arm 3 to move the article 5 from the accumulation region 11 to the destination region 12. Further, the control unit 42 controls the operation of the vacuum generator 63, the compressor 64, the electromagnetic valve 65, and the pressure sensor 66 based on the operation command of the article gripping mechanism 6, and also controls the operation of the suction pad 62 measured by the pressure sensor 66. The CPU calculates according to the value, and the suction pad 62 grips (sucks) the article 5 based on the calculation result. At the same time, the control unit 42 controls the operation of the compressor 64 and the air cylinder 74 based on the operation command of the article gripping mechanism 6 (lip deformation unit 7), and also responds to the operation status data read from the input / output circuit. The lip deforming unit 7 (link mechanism) is operated based on the calculation result in order to perform the calculation by the CPU and press the lip 62b. In these operation controls, the control unit 42 reads a predetermined program from the memory based on the operation command.

In the present embodiment, as an example, the planning unit 41 formulates the operation plans of the robot arm 3 and the article gripping mechanism 6, but the control device 4 has a plurality of planning units that individually formulate these operation plans. You may be doing it. Further, although the control unit 42 controls the operations of the robot arm 3 and the article gripping mechanism 6, the control device 4 may have a plurality of control units that individually control these operations. Alternatively, the control device that functions as the planning unit 41 and the control device that functions as the control unit 42 may be physically separated.

Regarding the operation of the cargo handling device 1 having such a configuration, specifically, the process of moving the article 5 from the accumulation region 11 to the destination region 12 (hereinafter referred to as the article movement process), the detection device 2, the robot arm 3, and This description will be described according to the control flow of the control device 4 for the article gripping mechanism 6. FIG. 9 shows a control flow of the control device 4 for the detection device 2, the robot arm 3, and the article gripping mechanism 6 in the article movement process.

When the article moving process is started, the robot arm 3 and the article gripping mechanism 6 are each in the initial state. The initial state of the robot arm 3 is a state in which the arm portion 32 is positioned at a reference position. The reference position is, for example, a position where the arm portion 32 does not interfere with either the accumulation region 11 or the movement destination region 12. The initial state of the article gripping mechanism 6 is a state in which the inside of the suction pad 62 is opened to the atmosphere (vacuum breakage) and the pressing bar 71 is positioned at the retracted position. Therefore, in the initial state, the solenoid valve 65 is closed, and the vacuum generator 63, the compressor 64, and the air cylinder 74 are all stopped.

In moving the article 5 from the accumulation area 11 to the destination region 12, the control device 4 causes the detection device 2 to detect the accumulation mode of the article group 5s in the accumulation area 11 (S101). Specifically, the operation is controlled by the planning unit 41, and the detection unit 21 (as an example, an RGB camera) captures an image showing the accumulation mode of the article group 5s in the integration region 11. The detection unit 21 gives the detection result (data of the captured image) to the analysis unit 22. The number of captured images is arbitrary, and may be one, or may be a plurality of images in which the focal length and the angle of view are appropriately changed.

The analysis unit 22 analyzes the detection result (image data) given by the detection unit 21 (S102). By analysis, the analysis unit 22 provides information for identifying modes such as position, contour, size, orientation, posture, overlap, boundary, and material of each article 5 of the article group 5s accumulated in the accumulation area 11 ( (Analysis data) is output and given to the planning unit 41.

The planning unit 41 determines the existence / non-existence condition of the article based on the given analysis data (S103). The article presence / absence condition is a condition for determining whether or not the article 5 is accumulated in the accumulation area 11. For example, when some data concretely indicating the mode of the article 5 is given as the analysis data, the planning unit 41 has at least one article 5 present in the accumulation area 11 and the article existence / non-existence condition. Is determined to hold. On the other hand, when no data specifically indicating the mode of the article 5 is given as the analysis data, the planning unit 41 states that the article 5 does not exist in the accumulation area 11 and the article existence / non-existence condition is satisfied. Is not satisfied. In this case, only the analysis data of the image of the workbench, which is the integrated area 11, is given to the planning unit 41.

If the article presence / absence condition is not satisfied, the planning unit 41 ends the article moving process without formulating an operation plan for the robot arm 3 and the article gripping mechanism 6.
On the other hand, when the article existence / non-existence condition is satisfied in S103, the planning unit 41 selects the article 5 (hereinafter, referred to as the selected article) to be moved from the accumulation area 11 from the article group 5s (S104). The planning unit 41 identifies a selected article from the article group 5s based on a predetermined selection criterion corresponding to the analysis data. The selection criteria are, for example, the height position in the article group 5s, the distance from the robot arm 3, the gap with another article 5, the position in the accumulation area 11, the material of the article 5 (including the packing state and the packaging state), and the like. .. Specifically, the one at the highest position in the article group 5s, the one at the position closest to the robot arm 3, the one farthest from the other articles 5, and the one near the center of the accumulation area 11. The planning unit 41 specifies an article having a material specified in advance as an article 5 that is easy to grip (adsorb) as an article to be selected. Alternatively, the planning unit 41 may specify the selected article using these as a composite selection criterion. Further, the planning unit 41 specifies attribute data such as the position, contour, size, orientation, posture, overlap, boundary, and material (including the packing state and the packing state) of the selected article based on the analysis data.

When the selected article is specified, the planning unit 41 sets the target gripping position of the selected article (S105). The target gripping position is a position where the suction pad 62 can stably suck the selected article when the selected article is sucked by the suction pad 62, and is a position where the lip 62b is brought into contact with the selected article. For example, the intersection (virtual point) with the axis A on the selected article corresponds to the target gripping position. Specifically, when the shaft core A is positioned so as to pass through the center of gravity of the selected article, the intersection of the shaft core A and the surface of the selected article is set as the target gripping position. The surface (adsorbed surface) of the selected article for which the target gripping position is set may be parallel to the horizontal plane (for example, the floor surface of the building of the distribution center), but the surface is not limited to this and is perpendicular to the horizontal plane or diagonally. Including the aspect of. Therefore, the selected article can be adsorbed by the adsorption pad 62 from any of the vertically upward direction, the horizontal direction, and the other directions regardless of the accumulation mode. Therefore, the selected article can be adsorbed by the adsorption pad 62 from the optimum direction according to the accumulation mode.

When the target gripping position is set, the planning unit 41 formulates an operation plan for the robot arm 3 and the article gripping mechanism 6. In formulating the motion plan of the robot arm 3, the planning unit 41 determines the path existence / non-existence condition (S106). As for the path existence / non-existence condition, the arm portion 32 is operated so that the gripping reference position of the suction pad 62 coincides with the target gripping position, and the target gripping position (grasping reference position) is moved to the moving destination region 12, and further, the moving destination region 12 ( This is a condition for determining whether or not there is a path for operating the arm unit 32 from the target release position (described later) to the reference position. The path existence / non-existence condition is determined by, for example, whether or not another article 5 or another obstacle that becomes an obstacle when the arm portion 32 is displaced on the assumed path is present. If there is no other article 5 or the like that hinders the operation and the operation route can be secured, the planning unit 41 determines that the route existence / non-existence condition is satisfied. On the other hand, if there is another article 5 that hinders the operation and the operation route cannot be secured, the planning unit 41 determines that the route existence / non-existence condition is not satisfied.

If the route existence / non-existence condition is not satisfied, the planning unit 41 selects the selected article again (S104). In this case, the planning unit 41 specifies another selected article from the articles 5 other than the once specified selected article.

On the other hand, when the path existence / non-existence condition is satisfied in S106, the planning unit 41 formulates an operation plan of the robot arm 3 based on the available operation path, and operates the article gripping mechanism 6 based on the operation plan of the robot arm 3. Formulate a plan (S107). In addition, the planning unit 41 assigns the formulated information (operation command) of these operation plans to the control unit 42.

When the motion plans of the robot arm 3 and the article gripping mechanism 6 are given, the control unit 42 controls the motion of the robot arm 3 and the article gripping mechanism 6 based on these motion plans. Here, the control unit 42 sets the internal pressure of the suction pad 62 as a negative pressure (S108). When the internal pressure of the suction pad 62 is set to negative pressure, the control unit 42 opens the solenoid valve 65 and operates the compressor 64, the vacuum generator 63, and the pressure sensor. As a result, the control unit 42 supplies compressed air from the compressor 64 to the vacuum generator 63, and evacuates the inside of the suction pad 62 to create a negative pressure. At that time, the pressure sensor 66 measures the internal pressure of the suction pad 62 and applies the measured value to the control unit 42. Hereinafter, the condition that is satisfied when the inside of the suction pad 62 is negative pressure is referred to as the first control condition.

When the first control condition is satisfied, the control unit 42 determines the attribute condition (S109). The attribute condition is a condition for determining whether or not the form of the article 5 is deformable based on the material of the article 5, and specifically, a condition for determining whether or not the selected article is a flexible object. Is. In determining the attribute condition, the control unit 42 acquires the attribute data of the selected article specified by the planning unit 41. Based on the attribute data, the attribute condition is, for example, whether or not the material of the selected article is deformed by its own weight to change its form when adsorbed by the adsorption pad 62, or whether the selected article is a vinyl film, wrapping paper, or the like. It is judged by whether or not it is packaged. When the material is deformed by its own weight to change its shape when sucked by the suction pad 62, or when it is wrapped in a vinyl film, wrapping paper, or the like, the control unit 42 determines that the selected article has deformability 5 ( It is a flexible object), and it is determined that the attribute condition is satisfied. On the other hand, if the material is not a material that changes its shape by being deformed by its own weight when sucked by the suction pad 62, or if it is not wrapped with a vinyl film, wrapping paper, or the like, the control unit 42 has deformability of the selected article. It is determined that the attribute condition is not satisfied, not the article 5 (flexible object) (for example, a box object).

When the attribute condition is satisfied, the control unit 42 displaces the pressing bar 71 from the retracted position to the pressing position (S110). That is, the pressing bar 71 is positioned at the pressing position from the retracted position, which is the initial position. In displacement of the pressing bar 71, the control unit 42 operates the compressor 64 and the air cylinder 74 to supply compressed air from the compressor 64 to the air cylinder 74. As a result, the piston rod 742 moves back and forth with respect to the cylinder body 741, and the cam follower 715 moves from one end 733 of the cam groove 732 to the other end 734. As a result, the pressing bar 71 is displaced to the pressing position, and the contact portion 713 radially presses the lip 62b to deform it. Hereinafter, the condition that is satisfied when the lip 62b is deformed in this way is referred to as a second control condition.

On the other hand, in S109, when the attribute condition is not satisfied, the control unit 42 positions the pressing bar 71 at the retracted position (S111). Since the pressing bar 71 is positioned at the retracted position in the initial state, it is positioned at the retracted position at this point. Therefore, here, the control unit 42 confirms that the pressing bar 71 is positioned at the retracted position, and returns the pressing bar 71 to the retracted position when it is positioned at a position other than the retracted position. At that time, the control unit 42 operates the compressor 64 and the air cylinder 74 to supply compressed air from the compressor 64 to the air cylinder 74. When the pressing bar 71 is positioned at the retracted position, the lip 62b is not deformed and the second control condition is not satisfied.

With the pressing bar 71 positioned at either the pressing position or the retracting position, the control unit 42 operates the arm unit 32 to cause the suction pad 62 to grip (suck) the selected article (S112). Hereinafter, such an operation of the arm portion 32 is referred to as a gripping operation. When the selected article is the deformable article 5 (flexible object), the gripping operation is performed on the condition that both the first control condition and the second control condition are satisfied. On the other hand, when the selected article is an article 5 having no deformability (a box as an example), the gripping operation is performed on the condition that the first control condition is satisfied and the second control condition is not satisfied. Will be.

In the gripping operation, the control unit 42 operates the arm unit 32 so that the gripping reference position of the suction pad 62 coincides with the target gripping position according to the operation path determined by the planning unit 41. Meanwhile, the control unit 42 positions, for example, the suction pad 62 above the selected article and directs the lip 62b toward the selected article. Subsequently, the control unit 42 lowers the arm unit 32 so that the gripping reference position overlaps with the target gripping position. Since the internal pressure of the suction pad 62 is negative, the suction pad 62 is attracted to the selected article with the lip 62b in close contact with the selected article.

Next, the control unit 42 determines the gripping suitability condition (S113). The gripping suitability condition is a condition for determining whether or not the selected article is properly gripped by the suction pad 62. In determining the gripping suitability condition, the control unit 42 compares the internal pressure value of the suction pad 62 given by the pressure sensor 66 with a predetermined threshold value (hereinafter, referred to as gripping suitability value). The gripping appropriate value is set according to, for example, the size and weight of the selected article, the surrounding environment, etc., is held in the storage device, and is read into the memory as a parameter when the gripping suitability condition is determined. Although not particularly limited, the guideline for the appropriate gripping value may be a value in which the gauge pressure is in the range of about -20 kPa to -40 kPa. Further, the gripping appropriate value may be a constant value or a variable value set according to the size and weight of the selected article.

In the present embodiment, as an example, when the internal pressure value is equal to or less than the gripping appropriate value, the control unit 42 determines that the selected article is properly gripped by the suction pad 62 and the gripping suitability condition is satisfied. On the other hand, when the internal pressure value exceeds the gripping appropriate value, the control unit 42 determines that the selected article is not properly gripped by the suction pad 62 and the gripping suitability condition is not satisfied. However, the success or failure of the gripping suitability condition when the internal pressure value is the gripping suitability value may be the opposite of the above.

If the gripping suitability condition is not satisfied, the control unit 42 grips the arm unit 32 again (S112). In this case, for example, a time-out process for terminating the article moving process after a lapse of a predetermined time, a retry process for terminating the article moving process when the gripping suitability condition is not satisfied even if the gripping operation is repeated a predetermined number of times, etc. are combined. You may. Furthermore, the control unit 42 may execute a predetermined abnormality process. For example, by issuing warnings such as lighting (blinking) of a warning light, sounding of a warning sound, and displaying a warning message, it is possible to thoroughly inform the error that occurred during the gripping operation.

On the other hand, in S113, when the gripping suitability condition is satisfied, the control unit 42 operates the arm unit 32 to displace it to the movement destination region 12 (S114). Hereinafter, such an operation of the arm portion 32 is referred to as a release operation. In operating the arm unit 32 in the release operation, the control unit 42 operates the arm unit 32 according to the operation path defined by the planning unit 41. During that time, the control unit 42 pulls up the selected article adsorbed on the suction pad 62 from the accumulation region 11, and operates the arm unit 32 so that the gripping reference position of the suction pad 62 coincides with the target release position. The target release position is a position where the selected article can be appropriately released from the suction pad 62 when the selected article adsorbed on the suction pad 62 is released, and is, for example, an arbitrary position vertically above the mounting surface of the moving destination region 12. The position. The target release position may be a fixed position or a variable position set according to the size and weight of the selected article.

Next, the control unit 42 opens the inside of the suction pad 62 to the atmosphere (vacuum break) (S115). When opening the inside of the suction pad 62 to the atmosphere, the control unit 42 closes the solenoid valve 65 and stops the supply of compressed air from the compressor 64 to the vacuum generator 63. As a result, the inside of the suction pad 62 is evacuated and opened to the atmosphere. At that time, the pressure sensor 66 measures the internal pressure of the suction pad 62 and applies the measured value to the control unit 42.

Subsequently, the control unit 42 determines the release suitability condition (S116). The release suitability condition is a condition for determining whether or not the selected article is properly released from the suction pad 62. In determining the release suitability condition, the control unit 42 compares the internal pressure value of the suction pad 62 given by the pressure sensor 66 with a predetermined threshold value (hereinafter referred to as a release suitability value). The release appropriate value is set according to, for example, the size and weight of the selected article, the surrounding environment, etc., is held in the storage device, and is read into the memory as a parameter when the gripping suitability condition is determined. Although not particularly limited, the guideline of the appropriate release value may be about the same as the atmospheric pressure, for example, the gauge pressure may be a value in the range of about 0 kPa to about -5 kPa. Further, the appropriate release value may be a constant value or a variable value set according to the size and weight of the selected article.

In the present embodiment, as an example, when the internal pressure value is equal to or higher than the appropriate release value, the control unit 42 determines that the selected article is appropriately released from the suction pad 62 and the release suitability condition is satisfied. On the other hand, when the internal pressure value is less than the appropriate release value, the control unit 42 determines that the selected article is not properly released from the suction pad 62 and the gripping suitability condition is not satisfied. However, the success or failure of the release suitability condition when the internal pressure value is the release suitability value may be the opposite of the above.

If the release suitability condition is not satisfied, the control unit 42 releases the arm unit 32 again (S115). In this case, for example, a time-out process for terminating the article movement process after a lapse of a predetermined time, a retry process for terminating the article transfer process when the release suitability condition is not satisfied even if the release operation is repeated a predetermined number of times, etc. are combined. You may. Furthermore, the control unit 42 may execute a predetermined abnormality process. For example, by issuing warnings such as lighting (blinking) of a warning light, sounding of a warning sound, and displaying a warning message, it is possible to thoroughly inform the error that occurred during the release operation.

On the other hand, in S116, when the release suitability condition is satisfied, the control unit 42 operates the arm unit 32 to displace it to the reference position (S117). Hereinafter, such an operation of the arm portion 32 is referred to as an evacuation operation. In retracting the arm unit 32, the control unit 42 operates the arm unit 32 according to the operation path determined by the planning unit 41 and returns it to the reference position. At that time, if the pressing bar 71 is positioned at the pressing position, it is returned to the retracted position. As a result, the robot arm 3 and the article gripping mechanism 6 are each returned to the initial state.

When the arm unit 32 is retracted, the control unit 42 plans a signal indicating that a series of controls (article movement processing) in the operation plan of the robot arm 3 and the article gripping mechanism 6 formulated by the planning unit 41 have been normally completed. It is transmitted to the unit 41. When such control is normally completed, the control device 4 continues to perform the article moving process (S101 to S117) for moving the next article 5 from the accumulation area 11 to the moving destination area 12.

That is, the control device 4 repeats the predetermined control while the article 5 is accumulated in the accumulation area 11, that is, while the article existence / non-existence condition is satisfied in S103. Then, when the article 5 accumulated in the accumulation area 11 disappears, that is, when the article existence / non-existence condition is not satisfied in S103, the article movement process (S101 to S117) is terminated.

As described above, according to the article gripping mechanism 6 of the present embodiment and the cargo handling device 1 provided with the article gripping mechanism 6, depending on the attribute condition of the article 5, that is, depending on whether or not the selected article is a flexible object. The pressing bar 71 can be displaced. That is, the pressing bar 71 can be displaced based on the material of the selected article including the packed state and the packed state, and the lip 62b of the suction pad 62 can be deformed.

In FIGS. 10, 11, and 12, the selected article is a flexible object, a box object in which the surface to be adsorbed 51 is a flat surface, and a box object in which the surface to be adsorbed 51 is a non-flat surface (curved surface). An example of the gripping mode in the article gripping mechanism 6 is shown. Each figure (a) is a diagram schematically showing a gripping mode from the horizontal direction, and each figure (b) is a diagram schematically showing a gripping mode from above in the vertical direction.

As shown in FIGS. 10A and 10B, when the selected article is the flexible object 5a, the pressing bar 71 is positioned at the pressing position. At this time, the contact portion 713 radially presses the lip 62b to deform it. In the present embodiment, as an example, the lip 62b is pressed at four points by the four pressing bars 71a to 71d, and the entire lip 62b is deformed so as to undulate substantially evenly in the circumferential direction. As a result, even when the flexible object 5a is deformed by its own weight during adsorption, the lip 62b can be deformed following the deformation of the flexible object 5a. At that time, since the lip 62b is deformed so as to grip the flexible object 5a starting from the contact portion 713, the shape of the lip 62b is maintained to some extent by the contact portion 713, and the gripping force (adsorption force) with respect to the flexible object 5a is maintained. Can be raised appropriately.

As shown in FIGS. 11A and 11B, when the selected article is a box 5b having a flat surface-shaped surface to be attracted 51, the pressing bar 71 is positioned at the retracted position. At this time, the contact portion 713 contacts the surface to be attracted 51 and supports the box object 5b without pressing the lip 62b. The surface to be adsorbed 51 is a surface of the surface of the box 5b that has a target gripping position. In the present embodiment, as an example, the box 5b is supported at four points by the contact portions 713 of the four pressing bars 71a to 71d. As a result, when the box object 5b gripped (adsorbed) by the lip 62b is moved, vibration of the box object 5b or the like is suppressed, and the posture can be stabilized.

As shown in FIGS. 12A and 12B, when the selected article is a boxed object 5c having a non-flat surface-like surface to be adsorbed, for example, a curved surface-like surface to be adsorbed 51, the pressing bar 71 is , Positioned in the retracted position. At this time, the contact portion 713 is positioned so as to be able to contact the surface to be attracted 51 without pressing the lip 62b. Therefore, when the lip 62b is adsorbed on the box 5c, even if the surface to be adsorbed 51 is curved, the contact portion 713 does not interfere with the curved surface to be adsorbed (curved surface) 51. The entire lip 62b can be appropriately deformed along the line. As a result, the gripping force (adsorption force) for the boxed object 5c can be appropriately increased. Further, even when the box object 5c gripped (sucked) by the lip 62b vibrates during movement, the contact portion 713 can be brought into contact with the vibrating box object 5c, so that the vibration is minimized. It becomes possible. As a result, the posture of the box 5c when moving can be stabilized. When the lip 62b is attracted and lifted, the flat surface to be adsorbed 51 bends and deforms into a curved shape due to the weight of the selected article, as in the states shown in FIGS. 12 (a) and 12 (b). It becomes the state of. Therefore, even in this case, the same posture stabilizing effect can be obtained when the box 5c is moved.

As described above, according to the present embodiment, the articles 5 of various materials such as the flexible objects 5a packaged with a vinyl film or the like and the boxes 5b and 5c packed with a cardboard box or the like are mixed as the articles 5 to be gripped. Even in this case, these articles 5 can be appropriately gripped regardless of whether or not the form is deformed. Therefore, various suction pads 62 corresponding to the articles 5 of various materials, and in short, various tools 33 are not particularly required, and in particular, the flexible object 5a and the deformable box object 5c are included in the articles 5 to be gripped. Even in the case, these can be appropriately gripped by a single suction pad 62. Therefore, for example, a tool changer for exchanging the tool 33 corresponding to the article 5 to be gripped becomes unnecessary, and the cargo handling device 1 is miniaturized, the processing speed of the article moving process is improved (high speed), and the cost is reduced. be able to. In terms of high speed, the pressing bar 71 can suppress the vibration of the article 5 during movement due to the flexibility of the suction pad 62, so that it can sufficiently withstand high speed movement.

Although the embodiments of the present invention have been described above, the above-described embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

For example, the number of each component in the article gripping mechanism 6 may be an arbitrary number according to the mode (shape, size, weight, material, etc.) of the article 5 to be gripped. As in the modified example shown in FIG. 13, the article gripping mechanism 6 may include a plurality of suction pads 62. As a result, the article 5 can be adsorbed by the plurality of suction pads 62, and the posture of the article 5 at the time of movement can be more stabilized. In this modification, the lip deformation portion 7 of the article gripping mechanism 6 shares the bearing 722 and the drive member (air cylinder) 74 of the connecting member 72 with a plurality of suction pads 62. Further, each suction pad 62 is connected to a common vacuum generator 63, a compressor 64, a solenoid valve 65, and a pressure sensor 66, and the inside is negatively pressured or opened to the atmosphere (vacuum breakage). These common members may be individually provided for each suction pad 62. In this modification, for example, the intersection (virtual point) of the arm tip portion 32a with the rotation center axis A1 on the selected article corresponds to the target gripping position. In the modified example shown in FIG. 13, the same or similar configurations as those of the present embodiment (FIGS. 1 to 12) described above are designated by the same reference numerals in the drawings, and the description thereof will be omitted.

Further, the number of pressing bars 71 does not have to be an even number, and may be an odd number. For example, the three pressing bars 71 may be arranged in substantially the same phase (at substantially equal intervals in the circumferential direction) around a point on the axis A. In this case, these pressing bars 71 are connected by, for example, a ball joint or a universal joint, and three pressing bars 71 are driven by a driving member (air cylinder) so that the direction of pressing the lip 62b is closer to the axis A. ) 74 may be linked. Even when the number of pressing bars 71 is an even number, it is possible to connect these pressing bars 71 with a ball joint, a universal joint, or the like. Here, the form in which the pressing bar 71 is one is not particularly excluded, but in order to deform the entire lip 62b more appropriately, it is desirable that the pressing bar 71 is two or more.

In the present embodiment, the lip 62b is deformed by the lip deforming portion 7 which is a link mechanism. The mechanism applied to the lip deforming portion 7 is not limited to the link mechanism described above. In the present embodiment, the pressing bar 71 is bent at a bending angle θ1, and the cam follower 715 is moved along the cam groove 732 so that the contact angle θ2 of the contact portion 713 with respect to the lip 62b is an acute angle. Instead of this, for example, a simple linear motion mechanism may be used in which the pressing bar is straightened without being bent and the pressing bar is moved along the extending direction thereof. The moving direction of the pressing bar may be a direction in which the direction of pressing the lip approaches the axis A, but it can also be a direction parallel to the axis A (vertical direction).

Further, in the present embodiment, the lip 62b is deformed by the lip deforming portion 7 which is a link mechanism, and the lip 62b is deformed by applying an external force (pressing pressure) from the lip deforming portion 7. Alternatively or additionally, the lip itself may be deformable. For example, it is possible to form a lip by partially including a material whose rigidity changes (hardens or softens) or expands and contracts due to energization, heating, supply and discharge of compressed air, and the like. In this case, the lip may be deformed by controlling energization, heating, supply / discharge of compressed air, etc. according to the attribute condition of the article 5, that is, depending on whether the selected article is a flexible object.

1 ... cargo handling device, 2 ... detection device, 3 ... article moving device (robot arm), 4 ... control device, 5 ... article, 5a ... flexible object, 5b, 5c ... box object, 5s ... article group, 6 ... article gripping Mechanism, 7 ... Lip deformation part, 11 ... Accumulation area, 12 ... Movement destination area, 21 ... Detection part, 22 ... Analysis part, 31 ... Base part, 32 ... Arm part, 32a ... Arm tip part, 33 ... Tool, 41 ... Planning unit, 42 ... Control unit, 51 ... Adsorbed surface, 61 ... Base unit, 62 ... Adsorption part (adsorption pad), 62a ... Cylinder body, 62b ... Adhesion part (lip), 62c ... Transformation part, 62d ... Opening, 63 ... Vacuum generator, 64 ... Compressor, 65 ... Electromagnetic valve, 66 ... Pressure sensor, 67 ... First pipe, 68 ... Second pipe, 69 ... Joint, 71 (71a to 71d) ... Pressing member ( Press bar), 72 ... connecting member, 73 (73a to 73d) ... supporting member, 74 ... driving member, 621 ... one end (base end), 622 ... other end (tip), 711 ... base, 712 ... working part, 713 ... contact part, 714 ... through hole, 715 ... supported body (cam follower), 716 ... meshing part, 721 (721a, 721b) ... connecting shaft, 722 ... bearing, 731 ... support, 732 ... guide (cam groove) , 733 ... One end of the cam groove (displacement start point), 734 ... The other end of the cam groove (displacement end point), 741 ... Cylinder body, 742 ... Piston rod, A ... Shaft core, A1 ... Rotation center axis, C1 ... Outer circle , C2 ... Inner circle, L71 ... Contact length of contact portion, W62 ... Lip width, θ1 ... Bending angle, θ2 ... Contact angle.

Claims (7)

An article gripping mechanism provided at the tip of an arm of a robot arm that moves an article from an accumulation region to a desired region and grips the article so that it can be released.
It has a cylinder and a planar lip that opens from the axis of the cylinder toward the outer edge and is provided at one end of the cylinder, and the cylinder, the lip, and the lip come into contact with the article. A suction portion that sucks and grips the article in a state where the internal pressure of the system closed from the outside by the surface is reduced, and
The state of the lip is transitioned between a first state in which an external force is applied to the lip radially with respect to the shaft core to deform the lip and a second state in which no external force is applied to the lip and the lip is not deformed. With the lip deformation part to make
An article gripping mechanism including a base portion attached to the arm tip portion and supporting the suction portion and the lip deformed portion on the arm tip portion. The lip deformed part is
A pressing member that displaces with respect to the base portion and presses the lip to deform it.
A drive member that displaces the pressing member and
A connecting member that connects the pressing member to the driving member,
The article gripping mechanism according to claim 1, further comprising a support member that supports the pressing member on the base portion so as to be able to transition between the first state and the second state. The support member
A support provided on the base portion and
The second aspect of claim 2, wherein a guide formed on the support and for moving the pressing member between a position corresponding to the first state and a position corresponding to the second state. Article gripping mechanism. The article gripping mechanism according to claim 3, wherein the path from the position corresponding to the first state of the guide to the position corresponding to the second state is provided along the direction intersecting the axis. .. A claim that the pressing member is continuous from a connecting position with the connecting member to a supporting position on the supporting member, and extends from the supporting position so that the direction of pressing the lip is a direction approaching the axis. Item 2. The article gripping mechanism according to item 2. An suction portion that opens from the axis of the cylinder toward the outer edge and contacts a planar lip provided at one end of the cylinder to suck and grip the article accumulated in the accumulation region, and an external force on the lip. An article gripping mechanism including a lip deforming portion that shifts the state of the lip to a first state in which the lip is deformed by giving the lip and a second state in which the lip is not deformed without applying an external force to the lip. ,
A robot arm having the article gripping mechanism at the tip of the arm and moving the article from the integrated region to a desired region.
A detection unit that detects the material of the article,
A cargo handling device for the article, comprising the robot arm and a control unit for operating the article gripping mechanism.
The control unit determines whether or not the shape of the article is deformable based on the material of the article detected by the detection unit, and when it is determined that the article is deformable, the lip deformed portion is subjected to the lip. To the first state, and when it is determined that the article does not have deformability, a cargo handling device that causes the lip to transition to the second state at the lip deforming portion. The control unit
When the article has deformability, the first control condition that is satisfied when the suction portion is negative pressure and the second control condition that is satisfied when the lip deformable portion deforms the lip are satisfied. On condition that all of them are satisfied, the lip is made to grip the article.
The cargo handling device according to claim 6, wherein when the article is not deformable, the lip grips the article on condition that the first control condition is satisfied and the second control condition is not satisfied. ..

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