JP6435400B2 - Working robot and gripper - Google Patents

Description

  The present invention relates to a work robot that takes an article placed on a shelf and a gripper thereof.

  In recent years, in order to flexibly respond to diversifying consumer needs, an increasing number of warehouses and factories handle many items such as mail order warehouses and high-mix low-volume production factories. One of the main tasks in such warehouses and factories is picking. This work is a work for picking up an ordered product or a part necessary for product production from a shelf in which they are stored. In the past, it was done manually, but in recent years it has become difficult to secure a labor force due to the declining birthrate and aging population, and higher productivity is required. Yes.

  Research and development have been conducted on work robots that pick up articles for the purpose of supporting human life in living spaces. For example, Patent Document 1 discloses an article management system having a function of moving an article in a living space using a robot.

  Patent Document 2 discloses a transfer device that conveys a ceramic columnar body using a flexible suction pad and a gripper provided with side supporters on both sides thereof.

JP 2004-249389 A JP 2002-18759 A

  Here, problems of the prior art will be described with reference to FIGS. FIG. 1 is an example of a schematic diagram showing a storage shelf 100a that stores a directly placed article 101 in a warehouse or factory. The storage shelf 100a in FIG. 1 stores a plurality of directly placed articles 101. The directly placed article 101 is mainly assumed to be a rectangular parallelepiped shaped article such as a tissue paper box, a shoe box, or a cardboard box, but it is not limited to that. In this way, when the directly placed articles 101 are placed directly on the storage shelf 100, they are generally placed without any gaps in order to increase the storage efficiency.

  On the other hand, as in the robot disclosed in Patent Document 1, the gripper is composed of two or more fingers, and a work robot that grips an article by sandwiching the article with the fingers holds the finger between the articles. Since there is no gap to put in, such a directly placed article 101 cannot be directly gripped.

  In order to hold an article placed on a shelf as shown in FIG. 1, it is necessary to use a suction pad as in the transfer device disclosed in Patent Document 2. The suction pad holds the article by generating a suction force with a vacuum pump and sealing the suction surface with the article.

  However, the transfer device disclosed in Patent Document 2 is intended for an article that is relatively small and particularly has a short length in the depth direction. Even if it tries to hold the directly placed article 101 as shown in FIG. 1 by the transfer device disclosed in Patent Document 2, a moment is applied to the suction pad due to the gravity applied to the directly placed article 101, and the suction pad is peeled off. End up. This problem will be described in detail with reference to FIG.

2, the conventional suction gripper 200 having a suction pad 15 _z, when gripping a straight ornament article 101 is an example of a schematic view showing a moment _{M z} acting on the suction pad 15 _z.

The suction pad 15 _z sucks the side surface located at a distance L from the center of gravity of the directly placed article 101 and attempts to hold the directly placed article 101 on which gravity G is applied. Then, a moment M _z due to the gravity G is applied to the suction pad 15 _z . The moment M _z is calculated by Equation 1.

  Although the moment M is applied to the suction pad 15 in the direction to peel off the sealing of the suction surface 17, the suction is fragile with respect to such a moment and is relatively easily peeled off. Since the side supporter attached to the transfer device disclosed in Patent Document 2 is attached only to the side of the suction bat, the effect on this moment is small, the distance L is long and the moment M is large. Not suitable for gripping articles.

  If the suction force is increased so that the conventional suction gripper 200 can hold even such an article, the vacuum pump for generating the suction force becomes large and cannot be mounted on the work robot.

  An object of the present invention is to provide a work robot capable of holding an article having a length in a depth direction stored on a shelf while being conscious of the above problems.

  In order to solve the above technical problem, a work robot is provided, comprising: a grip portion that holds an article; and a protrusion portion that is disposed on the gravitational direction side with respect to the grip portion.

  ADVANTAGE OF THE INVENTION According to this invention, the work robot in a warehouse or a factory comes to be able to hold | maintain the article | item with the length in the depth direction stored on the shelf.

It is an example of the schematic diagram showing the storage shelf 100a which stores the article 101 directly placed. It is an example of the schematic diagram showing the moment _Mz added to the suction pad 15 when holding the directly placed article 101 by the conventional suction gripper 200. It is an example of the block diagram of the work robot 10a in Example 1. FIG. It is an example of the block diagram of the gripper 11 in this invention. It is an example of the schematic diagram showing the moment M added to the suction pad 15 when gripping the directly placed article 101 by the gripper 11 in the present invention. It is an example of the flowchart showing operation | movement of the work robot 10a in Example 1. FIG. It is an example of the block diagram of the slider type gripper 24a in Example 2. FIG. It is an example of the block diagram of the slider type gripper 24b in Example 2. FIG. It is an example of the block diagram of the gripper 11 which has the diagonal side protrusion part 29 in this invention. It is an example of the schematic diagram showing the storage shelf 100b which stores the storage container 102 which stores the small article 103. FIG. It is an example of the block diagram of the working robot 10c in Example 3. FIG. It is an example of the schematic diagram showing a mode that the work robot 10c in Example 3 hold | maintains the small article 103x which exists in the storage container 102x.

  Embodiments will be described below with reference to the drawings.

  In the present embodiment, an example of a work robot 10a capable of holding a directly placed article 101 placed on a storage shelf 100a as shown in FIG. 1 will be described. In the present embodiment, the directly placed article 101 is stored in the storage shelf 100a, but an article placed on a table such as a table or a desk can also be targeted. 1 has a rectangular parallelepiped shape, but the target held by the work robot 10a is not limited to a rectangular parallelepiped object. However, the directly placed article 101 has a surface on which a general suction pad 15 can be sucked, and the surface needs to face the front side.

  FIG. 3 is an example of a configuration diagram of the work robot 10a in the present embodiment. The work robot 10 a includes a gripper 11, a manipulator 12, a suction force generator 13, and a control unit 14. Further, the work robot 10a in the present embodiment is assumed to move in a factory or a warehouse, and includes a traveling unit 19, a power supply unit 18, and an ambient environment measurement sensor 22. Further, the work robot 10a in this embodiment recognizes the detailed position and posture of the directly placed article 101 on the spot, and includes an article measurement sensor 23.

  However, in the present invention, the work robot 10 a does not necessarily need to include the traveling unit 19, the power supply unit 18, and the week environment measurement sensor 22. For example, in a situation where the work place to which the directly placed article 101 is to be supplied is close to the storage shelf 100a and the manipulator 12 can move the gripper 11 to both the storage shelf 100a and the work place without running the work robot 10a. The work robot 10a may not include the traveling unit 19. Furthermore, in this case, the power may be supplied from the outside through an outlet or the like, and the power supply unit 18 may not be provided. The ambient environment measurement sensor 22 is used for the work robot 10a to recognize its own position and orientation from time to time, but if the work robot 10a does not run, the position and orientation of the work robot 10a can be taught in advance. Well, there is no need to recognize from moment to moment. In such a case, the ambient environment measurement sensor 22 may not be provided.

  In the case where the work robot 10a is fixedly installed, the storage shelf 100a may be movable, and the transfer robot may transfer the storage shelf 100a to the workable range of the work robot 10a.

  In the present invention, the work robot 10 a does not necessarily need to include the object measurement sensor 23. For example, if the detailed position and orientation of the directly placed article 101 can be taught in advance to the work robot 10a, it is not necessary to recognize the detailed position and orientation of the directly placed article 101 on the spot. In such a case, the object measurement sensor 23 may not be provided.

  The traveling unit 19 in this embodiment includes two wheels attached to the left and right, two rotary motors assigned to each wheel, and one or more casters. The two motors operate independently. If the two wheels rotate in the same direction at the same speed, the work robot 10a goes straight. If the two wheels rotate in the opposite direction at the same speed, the work robot 10a Turn on the spot. However, in this invention, the traveling part 19 is not restricted to this structure, What is necessary is just to be movable to the arbitrary positions and orientations on a floor surface. For example, a wheel having a steering for changing the wheel axis may be used, an omni wheel capable of omnidirectional movement may be used, or a leg type mechanism may be used.

  The ambient environment measurement sensor 22 in the present embodiment is mounted as a laser distance sensor that measures the distribution of obstacle positions on a horizontal plane. However, the ambient environment measurement sensor 22 in the present invention is not limited to the laser distance sensor, and any sensor that can acquire sufficient information for recognizing the position and orientation of the work robot 10a may be used.

  The manipulator 12 in the present embodiment includes a column standing in the vertical direction, an arm of a three-link mechanism attached in the horizontal direction from the column, one linear actuator for moving the arm in the vertical direction along the column, It consists of three rotary motors that operate a three-link mechanism. With this configuration, the manipulator 12 can change the position of the gripper 11 attached to the tip of the arm with three degrees of freedom and the posture with one degree of freedom of vertical axis rotation. As a result, the suction surface 17 of the suction pad 15 attached to the gripper 11 can be brought into perpendicular contact with the side surface of the directly placed article 101 stored in the shelf 100a. However, the manipulator 12 according to the present invention is not limited to this configuration, and can be configured to realize an operation in which the suction surface 17 of the suction pad 15 attached to the gripper 11 is brought into perpendicular contact with the side surface of the directly placed article 101. If so, the number and type of actuators may be different.

  The article measurement sensor 23 in this embodiment is mounted as a distance image sensor (also referred to as a depth camera) that measures the distribution of obstacle positions within the field of view. However, the article measurement sensor 23 in the present invention is not limited to the distance image sensor, and may be any sensor that can acquire sufficient information for recognizing the position and orientation of the directly placed article 101. It may be implemented as a combination of a plurality of sensors such as a distance image sensor. In the present embodiment, the article measurement sensor 23 is attached on the gripper 11, and the article measurement sensor 23 is moved to a position and orientation where the directly placed article 101 stored in the shelf 100a can be measured by operating the manipulator 12. 23 can be moved. However, the attachment method of the article measurement sensor 23 in the present invention is not limited to this, and it is only necessary to install the article placement sensor 101 so that the article 101 can be measured.

  The suction force generator 13 in the present embodiment is mounted as a vacuum pump or a combination of a compressor and a vacuum generator, and further includes a vacuum valve that operates with an electrical signal. The suction force generator 13 and the suction pad 15 of the gripper 11 are connected by piping, and the suction force generator 13 can generate suction force on the suction pad 15 of the gripper 11.

  The control unit 14 in this embodiment is implemented as a combination of a CPU, a RAM, an external storage medium, and a communication function, such as a PC. The external storage medium is mounted as an HDD or a flash memory. The control unit 14 distributes the power supplied from the power supply unit 18 to each component device, and controls the manipulator 12, suction force generator 13, traveling unit 19, ambient environment measurement sensor 22, and article measurement sensor 23. . In addition, the control unit 14 analyzes the measurement results acquired from the ambient environment measurement sensor 22 and the article measurement sensor 23, and based on the results and information given in advance, the manipulator 12, the suction force generator 13, and the traveling unit 19. Make an action plan. The control unit 14 may be divided into a plurality of units and provided with different roles.

  The communication function of the control unit 14 in this embodiment is implemented as a wireless LAN or the like. However, in the present invention, when the work robot 10a is fixedly installed in the work space, it may be implemented as a wired LAN. The communication function of the control unit 14 is used when communicating with the overall management terminal 300 of the article transport system in a warehouse or factory. The work robot 10a receives a command from the overall management terminal 300 through the communication function of the control unit 14, and performs an article picking work based on the command. The work status is transmitted to the overall management terminal 300 and reported.

  The control unit 14 in the present embodiment performs an analysis process for recognizing its own position and orientation using the measurement result acquired from the ambient environment measurement sensor 22. As such an analysis process, for example, a method of matching the shape of the ambient environment map stored in advance in an external storage medium and the measurement result can be considered.

  The control unit 14 in this embodiment performs an analysis process for recognizing the position and orientation of the article using the measurement result acquired from the article measurement sensor 23. As such an analysis process, for example, a method of matching the shape model of an article stored in an external storage medium in advance with a measurement result can be considered.

  The power supply unit 18 in this embodiment is mounted as a battery, and supplies power to the manipulator 12, the suction force generator 13, the control unit 14, the traveling unit 19, the surrounding environment measurement sensor 22, and the article measurement sensor 23. At that time, the electric energy may be adjusted and supplied via the control unit 14. In the present invention, when the work robot 10a is fixedly installed in the work space, power may be supplied from an external power source to each device of the work robot 10a without providing the power supply unit 18. Even in this case, the electric energy may be adjusted and supplied via the control unit 14.

  The power supply unit 18 in this embodiment is configured to be rechargeable. For example, the power supply unit 18 may be detachable from the work robot 10a, and the power supply unit 18 may be charged with the power supply unit 18 detached from the work robot 10a. The power supply unit 18 and the external power supply may be connected while being attached to the work robot 10a. A plug that makes it possible may be provided. Alternatively, the work robot 10a is equipped with an electrode that is electrically connected to the power supply unit 18 and can be contacted from the outside, and a charging station is installed in the factory or warehouse, and the work robot 10a moves to the charging station and charges. The power supply unit 18 of the work robot 10a may be charged by the station automatically contacting its own electrode with the electrode of the work robot 10a and supplying power.

FIG. 4 illustrates three examples of the configuration of the gripper 11 in the present invention.
FIG. 4A is an example of a configuration diagram of the gripper 11a in the present invention. The gripper 11a has a suction pad 15a and a protrusion 16a.

  In this example and the following examples, a case where a suction pad is used will be described as a specific example, but an article can be held even by a method other than suction such as adhesion or physical fitting. Needless to say, the grip is good. Hereinafter, these may be collectively referred to as a grip portion. Further, the protruding portion may be a separate member from the gripper 11 or may be formed integrally.

  The suction pad 15 is connected to the suction force generator 13 through a pipe, and when the suction force generator 13 is operated by a command from the control unit 14, suction force is generated at the tip 21 of the suction pad. When the suction surface 17 of the suction pad 15 is in contact with the surface of the article in a state where the suction force is generated, and the suction surface 17 and the article surface are sealed without a gap, the suction surface 17 and the article surface are Adsorb. In order to increase the gripping force of the suction, the material of the suction surface 17 is preferably made of rubber. The protrusion 16 is located below the suction pad 15, in other words, on the gravity direction side of the suction pad 15, and the tip 20 of the protrusion is on the surface of the article while the suction pad 15 and the article are adsorbed. It is attached to come into contact with. Here, if the tip 21 of the suction pad is made of rubber, the length of the suction pad 15 is reduced compared to the normal time when the suction pad 15 and the article are sucked. Considering this, the length of the protrusion 16a of the gripper 11a is the same as the length of the suction pad 15a in a state where the suction pad 15a and the article are sucked. Since a strong load is applied to the protrusion 16, it is desirable that the material has rigidity that can withstand such as aluminum or carbon. Further, in order to increase the grip force for contact between the protrusion 16 and the article, the material of the tip 20 of the protrusion is preferably made of rubber. When the article is pressed against the protrusion 16a by the suction, a force is generated by which the protrusion 16a pushes back the article due to the law of action and reaction. By generating this force, the moment applied to the suction surface 17a of the suction pad can be relaxed.

  FIG. 4B is an example of a configuration diagram of the gripper 11b in the present invention. The gripper 11b uses a rubber bellows type, that is, a stretchable member for the tip 21b of the suction pad. By adopting the bellows type, the flexibility of the tip 21b of the suction pad becomes more remarkable, and when the suction surface 17b is brought into contact with the article surface, the strictness of the vertical degree can be relaxed. Further, in a state where the suction pad 15 and the article are sucked, the length is remarkably shortened as compared with the normal time. Here, the length of the protrusion 16 is shorter than the suction pad 15b at normal times, that is, before being sucked with the article, and longer than the suction pad 15b when the suction pad 15b and the article are sucked. To be. In other words, the suction pad is configured such that the length of the suction pad is longer than the length of the protrusion (is it a protrusion?) In the expansion / contraction direction of the suction pad or the protrusion direction of the protrusion. As a result, the article can be directed obliquely upward at the time of suction between the suction pad 15b and the article, and the moment applied to the suction surface 17b of the suction pad can be more relaxed than the gripper 11a.

  In addition, when the suction pad 15b and the article are sucked at the time of suction, the angle at which the article is tilted is calculated in advance from the length of the suction pad 15b, the length of the protrusion 16b, and the positional relationship between the suction pad 15b and the protrusion 16b. In addition, if the surface of the tip 20b of the projection that contacts the article is an inclined surface that faces obliquely upward according to the angle, the gripping force of the projection 16b can be further increased.

FIG. 4C is an example of a configuration diagram of the gripper 11c in the present invention. The gripper 11c includes four suction pads 15c to 15f in which the tip 20 of the suction pad has a bellows type. Thus, in the present invention, the gripper 11 may include a plurality of suction pads 15 in the vertical direction and the lateral direction in order to generate a strong suction force. Here, when the lengths of all the suction pads 15 are made uniform in normal times, all the suction pads 15 can be brought into close contact with the article surface at the same time, and a high suction force can be obtained instantaneously. Further, the length of the protrusion 16c is shorter than the length of the suction pad 15 in the normal state, like the gripper 11b shown in FIG. 4 (b), and the suction pad 15 and the article surface are adsorbed. It is desirable to make it longer than the length of the suction pad 15.
Here, as in the case of the gripper 11b shown in FIG. 4B, when the article is inclined obliquely upward when the suction pad 15 and the article surface are sucked, an extra load is not applied to the tip 21 of the suction pad. The center of the suction surface 17c or 17d of the upper suction pad, the center of the suction surface 17e or 17f of the lower suction pad, and the tip 20c of the protrusion are on the same straight line, in other words, each suction pad. It is desirable to adjust the amount of contraction of the tips 21c to 21d of the suction pads so that the contact surface of the protrusion and the contact surface of the protrusion are on the same plane. Here, the amount of contraction of the upper suction pad tips 21c and 21d is adjusted to be larger than the amount of contraction of the lower suction pad tips 21e and 21f. As an example of realizing this, The upper suction pad tips 21e, 21f are made thicker than the upper suction pad tips 21c, 21d, or the number of pleats is increased, or a rigid rubber is used as a material. Therefore, it is desirable to adjust so that the expansion / contraction rate of the tips 21c and 21d is larger than the expansion / contraction rate of the tips 21e and 21f of the lower suction pad. As a result of this adjustment, at the time of suction, the center of the suction surface 17 of each suction pad 15 lies on a plane determined by the inclination of the article and the tip of the protrusion 20c.

Further, similarly to the gripper 11b shown in FIG. 4B, it is desirable to incline the surface of the protrusion 20c that contacts the article in accordance with the angle at which the article is inclined.
In the gripper 11b shown in FIG. 4 (b), when the article is inclined so as to face obliquely upward at the time of suction between the suction pad 15b and the article surface, the upper part of the tip 21b of the suction pad has a large amount of shrinkage. Since the amount of shrinkage is small at the lower part of the tip 21b, a bending load is applied to the entire tip 21b of the suction pad. In order to reduce this load, it is desirable to manufacture by adjusting the lower part of the tip 21b of the suction pad to be thicker than the upper part or to increase the rigidity. As a result of this adjustment, the entire suction surface 17 of the suction pad 15b lies on a plane determined by the inclination of the product and the tip of the protrusion 20b during suction with the product. This adjustment is desirably performed also in the gripper 11c shown in FIG.

  FIG. 5 illustrates two examples of schematic diagrams representing moments applied to the suction pad 15 when the gripper 11 according to the present invention grips the directly placed article 101.

5 (a) is, when gripping a straight ornament article 101 by the gripper 11a shown in FIG. 4 (a), an example of a schematic view showing a moment M _a applied to the suction pads 15a.

The suction pad 15a sucks the side surface located at a distance L from the center of gravity of the directly placed article 101, and tries to hold the directly placed article 101 on which gravity G is applied. A protrusion 16a is attached to the gripper 11a at a distance D downward from the suction pad 15a and is in contact with the directly placed article 101. Although applied moment due to gravity G is the suction pad 15a, the moment is reduced by drag R _a from the protrusion 16a. The moment M _a received by the suction pad 15a is calculated by Equation 2.

Moment _{M a} in which suction pads 15a of the gripper 11a is experienced, as compared to the moment _{M z} which suction pads 15 _z of the conventional suction grippers 200 are subjected, it is learned smaller by the amount of the number 2 in the second term on the right side. As described above, the gripper 11 a having the protrusion 16 attached below the suction pad 15 can reduce the moment M applied to the suction pad 15.

FIG. 5B is an example of a schematic diagram showing the moment M _b applied to the suction pad 15b when the directly placed article 101 is gripped by the gripper 11b shown in FIG. 4B.

The suction pad 15b sucks the side surface located at a distance L from the center of gravity of the directly placed article 101, and tries to hold the directly placed article 101 on which gravity G is applied. A protrusion 16b is attached to the gripper 11a at a distance D downward from the suction pad 15b and is in contact with the directly placed article 101. Further, the tip 21b of the suction pad is a bellows type, and the directly placed article 101 is determined from the relationship between the length of the suction pad 15b and the length of the protrusion 16b when the suction surface 17b of the suction pad and the directly placed article 101 are sucked. It is lifted obliquely upward by an angle θ. Although a moment due to gravity G is applied to the suction pad 15b, the moment generating component is reduced because it is lifted obliquely upward by an angle θ, and the moment is reduced by the drag _Rb from the protrusion 16b. The The moment M _b received by the suction pad 15b is calculated by Equation 3.

Moment _{M b} where suction pad 15b of the gripper 11b is experienced, as compared to the moment _{M a} in which suction pads 15a of the gripper 11a is subjected, and cosθ is multiplied with a value of 1 or less gravity G, be smaller by that amount I understand. In this manner, the tip 21 of the suction pad is made into a bellows type, and the length of the protrusion 16 is shorter than the suction pad 15 at the normal time and longer than the suction pad 15 at the time of suction with the article surface, thereby The moment M applied to the pad 15 can be further reduced.

  FIG. 6 is an example of a flowchart showing the operation of the work robot 10a according to the first embodiment.

  The flowchart of FIG. 6 starts from a state in which the overall management terminal 300 determines that the work robot 10a is on standby and the work table 400x needs the directly placed article 101x (1001). The work robot 10a notifies the general management terminal 300 of the standby position at the start of standby, and the general management terminal 300 knows the standby position of the work robot 10a.

  First, the overall management terminal 300 creates a command for the work robot 10a, transmits the command to the work robot 10a via a wireless LAN or a wired LAN, and the work robot 10a receives the command (1002). As a command to the work robot 10a, the overall management terminal 300 uses the position and orientation of the storage shelf 100x, the position and orientation of the work table 400x, and the standby position of the work robot 10a to store the directly placed article 101x. Storage shelf route when moving to the near side, work platform route when moving from the front of the storage shelf 100x to the front of the work table 400x, approximate position and posture of the directly placed article 101x in the storage shelf 100x, direct placement Information including the type of the article 101x is created and transmitted to the work robot 10a. Here, when the work robot 10a is fixedly used and used, the command is only two pieces of information on the approximate position and posture of the directly placed article 101x and the type of the directly placed article 101x. When the detailed position and orientation of the directly placed article 101x in the storage shelf 100x are known, the detailed position and orientation are transmitted as command information instead of the approximate position and orientation.

  The work robot 10a that has received the command autonomously moves to the front of the storage shelf 100x along the route to the storage shelf (1003). At that time, the work robot 10a sometimes uses the measurement result of the ambient environment measurement sensor 22 and the ambient environment map stored in the external storage medium in advance to change its position and orientation from time to time by the method described in Non-Patent Document 1. Recognize every moment. Further, the left and right wheels of the traveling unit 19 are controlled on the basis of the storage shelf route and the position and orientation of the traveling unit 19 to move along the storage shelf route. As an example of the method, a point closest to its own position on the storage shelf route is specified, and a point on the route ahead by a predetermined length from that point is set as the nearest target position, and from its own position. There is a method of determining the rotational speeds of the left and right wheels of the traveling unit 19 according to the difference between the direction to the nearest target position and the direction of itself. As a result of this autonomous movement, after arriving in front of the shelf 100x, which is the end of the path to the storage shelf, based on the position and orientation of the shelf and the position and orientation of the shelf 100x, the orientation of itself is set to face the shelf 100x. Change and stop. Here, when the work robot 10a is fixedly installed and used, the operation 1003 is omitted.

  Subsequently, the work robot 10a measures the directly placed article 101x in the storage shelf 100x using the article measurement sensor 23 (1004). At that time, the work robot 10 a determines that the directly placed article 101 x is within the measurement range of the article measurement sensor 23 based on the approximate position and orientation of the directly placed article 101 x in the storage shelf 100 x included in the command from the overall management terminal 300. The position and orientation of the article measurement sensor 23 are changed using the manipulator 12 so as to enter. Here, if the command from the overall management terminal 300 includes the detailed position and orientation of the directly placed article 101x in the storage shelf 100x, the operation 1004 is omitted.

  After measuring the directly placed article 101x, the work robot 10a recognizes the detailed position and orientation of the directly placed article 101x using the measurement result of the operation 1004 (1005). At this time, the work robot 10a uses the measurement result of the operation 1004 and the shape model of the directly placed article 101x stored in the external storage medium in advance, and details of the directly placed article 101x by the method described in Non-Patent Document 2. Recognize the correct position and posture. Here, when the command from the overall management terminal 300 includes the detailed position and orientation of the directly placed article 101x in the storage shelf 100x, the operation 1005 is omitted.

  After the detailed position and orientation of the directly placed article 101x to be picked are obtained, the work robot 10a makes the suction surface 17 of the suction pad 15 attached to the gripper 11 perpendicular to the side face of the directly placed article 101x. The manipulator 12 is controlled so as to come into contact with (1006). Subsequently, the suction force generator 13 is operated to generate a suction force on the suction pad 15, thereby sucking the suction surface 17 of the suction pad 15 and the side surface of the directly placed article 101x (1007). At this time, in order to ensure suction, the manipulator 12 may be operated so as to press the suction pad 15 in a direction perpendicular to the side surface of the article 101x. Moreover, it can also be confirmed whether it attracted | sucked by attaching a vacuum pressure sensor to the suction force generator 13, and seeing the change of a vacuum pressure. After the suction, the work robot 10a controls the manipulator 12 to pull the gripper 11 along the normal direction of the side surface of the directly placed article 101x (1008). By this operation, the directly placed article 101x can be pulled out from the shelf 100x without contacting the surrounding articles. Here, by the protrusion 16 attached to the gripper 11, the directly placed article 101x is stably held by the gripper 11 even after being pulled out of the shelf 100x.

  After holding the directly placed article 101x by operation 1008, the work robot 10a autonomously moves to the front of the workbench along the workbench route specified in the command of the overall management terminal 300 (1009). The method of autonomous movement is the same as operation 1003. As a result of this autonomous movement, after arriving in front of the work platform 400x, which is the end of the work platform route, the self-facing to the work table 400x based on its own position and orientation and the position and orientation of the work table 400x Change the direction of and stop. Here, when the work robot 10a is fixedly installed and used, the operation 1009 is omitted.

  After facing the work table 400x, the work robot 10a controls the manipulator 12 and the suction force generator 13 so as to place the directly placed object 101x held on the work table 400x (1010). The work robot 10a controls the manipulator 12 so that the directly placed object 101x is placed on the work table 400x based on its own position and orientation and the position and orientation of the work table 400x. Thereafter, the operation of the suction force generator 13 is stopped, and the side surface of the directly placed object 101 x is separated from the suction surface 17 of the suction pad 15. Here, it is possible to confirm that the side surface of the directly placed object 101x is separated from the suction surface 17 of the suction pad 15 by attaching a vacuum pressure sensor to the suction force generator 13 and observing the change in vacuum pressure.

Finally, the work robot 10a transmits information that the work has been completed to the overall management terminal 300 via a wireless LAN or a wired LAN (1011). At that time, the work robot 10a with the traveling unit 19 transmits its own position and orientation to the overall management terminal 300 together. When the overall management terminal 300 receives the work completion report and the work robot 10a enters the standby state, the picking work is finished (1012).
The distance D between the suction pad 15 of the gripper 11 and the protrusion 16 is preferably as large as possible. However, when handling a wide variety of articles, if the distance D is too large, an article in which the suction surface 17 of the suction pad 15 and the tip 20 of the protrusion cannot simultaneously contact the side surface of the article depending on the height of the side surface of the article. Also come out. Therefore, for each article, a moment M _z applied to the conventional suction gripper 200 expressed by Equation 1 is obtained, and an article that cannot withstand the moment M _z only by the suction pad 15 from the relationship between the suction force generator 13 and the suction pad 15. Only the object supported by the protrusion 16 is used. Among the targeted articles, the one having the smallest height of the side face of the article is selected, and the distance D is determined based on the side face height of the selected article.

  The protrusion 16 of the gripper 11 is subjected to the same load as the drag R from the protrusion 16 due to the law of action and reaction. In order to support the load, the protrusion 16 needs a certain thickness, but if it is too thick, a part of the tip 20 of the protrusion protrudes from the side surface of the article. Then, the center of the drag R from the actual protrusion 16 approaches the suction pad 15 and the distance D between the suction pad 15 and the protrusion 16 is shortened. Therefore, it is desirable to keep the thickness of the protrusion 16 small within a range that can withstand the load received from the article.

Assuming that the maximum moment that the suction pad 15a of the gripper 11a can withstand is M _m , the load F _m that the protrusion 16a must withstand is expressed by Equation 4.

The width of the protrusion 16a W, a thickness B, and the length and H, when the E the Young's modulus of the material, buckling load F _k of the load protrusion 16a can not withstand, i.e. projections 16a number 5 It is represented by

Therefore, the minimum value B _m of the thickness of the protruding portion 16a is represented by Equation 6.

In the gripper 11b, the same state as that of the gripper 11a occurs immediately before the article is inclined obliquely upward. Therefore, even in the projections 16b, the minimum value of the thickness thereof becomes B _m of 6.

  Further, the gripper 11b or the gripper 11c having a feature of lifting the directly placed object 101 obliquely upward when the suction pad 15 and the directly placed object 101 are sucked is formed on the side of the suction pad 15 with an oblique side protrusion that is aligned with the inclination. By having 29, more stable gripping becomes possible. FIG. 9 is an example of a configuration diagram of the gripper 11b in which the oblique side protrusion 29 is attached to the gripper 11b.

  In this embodiment, instead of the gripper 11 in the first embodiment, a slider gripper 24 is provided, and the distance D between the suction pad 15 and the protrusion 16 in the slider gripper 24 is set to the side surface height of the object to be held. An example of the work robot 10b that is variable according to the above will be described.

  The only difference between the work robot 10 b in the present embodiment and the work robot 10 a in the first embodiment is that a slider gripper 24 is provided instead of the gripper 11.

FIG. 7 is an example of a configuration diagram of the slider-type gripper 24a in the present embodiment. Similarly to the gripper 11 in the first embodiment, the slider gripper 24a includes a protrusion 15g below the suction pad 15g, in other words, on the gravity direction side of the suction pad, and further, the suction pad for moving the suction pad 15g up and down. The linear actuator 25 is provided. For the suction pad 15g and the protrusion 16g, the combination of the suction pad 15 and the protrusion 16 in the gripper 11 described with reference to FIG. 4 can be used as it is. By such a configuration, depending on the side the height of the holding object article can be a distance D _g between the protrusion 16g and the suction pad 15g variable. The distance D _g is while in contact with the side surface of the suction surface 17g entire holding object article of the suction pads 15 g, on the condition that it is possible to contact the entire tip 20g of the projecting portion on the side surface of the holding target object, which can be It is desirable to make it as long as possible.

Further, since the distance D _g between the protrusion 16g and the suction pad 15g to the variable, the inclination angle and the tip 20g of the projecting portion, the tip 21g of the suction pad in the state where the suction pad 15g and the article side is adsorbed The optimum value of the inclination angle differs depending on the article to be held. Therefore, an average value is adopted for these inclination angles.

  Further, the slider-type gripper 24a having a feature of lifting the directly placed object 101 obliquely upward when the suction pad 15g and the directly placed object 101 are sucked is an oblique side protrusion attached to the gripper 11b as shown in FIG. 29 may be attached to the side of the suction pad 15g according to its inclination.

  When the work robot 10b includes the slider gripper 24a, the control unit 14 and / or the power supply unit 18 supplies power to the slider gripper 24a, and the control unit 14 controls the slider gripper 24a.

The operation of the work robot 10b including the slider gripper 24a is basically the same as that of the work robot 10a in the first embodiment. However, when a command is received from the overall management terminal 300, the suction pad linear actuator 25 of the slider gripper 24a is driven based on the product type information of the directly placed article 101x to be picked included in the command, and the suction pad operation is applied to change the distance _{D g} between 15g and the protrusion 16g.

  FIG. 8 is an example of a configuration diagram of the slider gripper 24b in the present embodiment. Similar to the gripper 11 in the first embodiment, the slider gripper 24b includes a protrusion 16h below the suction pad 15h. However, the tip 21h of the suction pad is a bellows type. Further, the protrusion 16h has a step, and the lower step is longer. The upper end of the protrusion 16h is a holding contact surface 27 that contacts the directly placed object 101 while holding the directly placed object 101, and the lower end of the protrusion 16h holds the directly placed object 101. This is the pre-holding contact surface 28 that comes into contact with the directly placed object 101 before performing. Normally, the suction pad 15h is longer than the protrusion 16h, and when the suction surface 17h of the suction pad 15h and the directly placed article 101 are sucked, the suction pad 15h is longer than the upper portion of the protrusion 16h. Make it shorter. Unlike the slider gripper 24a, the slider gripper 24b has a suction pad linear slider 26 that does not have an actuator.

The suction pad 15h of the slider gripper 24b can adopt the same contrivance as the suction pad 15b in the first embodiment, and the holding contact surface 27 can adopt the same contrivance as the tip 20b of the protruding portion in the first embodiment. Further, a plurality of suction pads 15h may be attached like the gripper 11c in the first embodiment, and the suction pads 15h and the holding contact surface 27 are the same as the suction pads 15c to 15f and the tip 20c of the protruding portion in the first embodiment. Can be adopted. However, as with slider grippers 24a, suction pad 15h and the distance D _h of the protrusion 16h from that variable, the inclination angle and the holding time of the contact surface 27, a suction pad 15h and the article side surface adsorbed The optimum value of the inclination angle of the tip 21h of the suction pad in the state of being different depends on the article to be held. Therefore, an average value is adopted for these inclination angles.

  Furthermore, the slider-type gripper 24b having a feature of lifting the directly placed object 101 obliquely upward when the suction pad 15h and the directly placed object 101 are sucked is an oblique side protrusion attached to the gripper 11b as shown in FIG. 29 may be attached to the side of the suction pad 15h in accordance with its inclination.

The operation of the work robot 10b including the slider gripper 24b is basically the same as that of the work robot 10a in the first embodiment. However, an operation of changing the distance D _h between the suction pad 15h of the slider gripper 24b and the protrusion 16 is added between the operation 1007 and the operation 1008 shown in FIG. This operation will be described with reference to FIG.

  When the suction pad 15h and the directly placed object 101a are sucked, first, the side surface of the directly placed object 101a and the pre-holding contact surface 28 come into contact with each other. At this time, it has not been pulled out from the storage shelf 100 yet and is placed on another directly placed object 101b. In this state, when the work robot 10b moves the manipulator 12 downward so as to pull the slider gripper 24b vertically downward, the height of the suction pad 15h remains unchanged, and the other slider grippers 24b move downward. Move by moving mechanism. Since the pre-holding contact surface 28 moves so as to slide on the side surface of the directly placed object 101a, the surface of the pre-holding contact surface 28 is preferably made of a slippery material.

  When the slider gripper 24b is further lowered, the side surface of the directly placed object 101a moves away from the holding surface contact surface 28. Then, the tip 21h of the suction pad further shrinks, attracts the directly placed object 101a, and the edge formed by the side surface and the bottom surface of the directly placed object 101a comes into contact with the contact surface 27 when the slider gripper 24b is held. Here, the lowering of the slider type gripper 24b is stopped, and the operation proceeds to the operation 1008 shown in FIG.

  The amount by which the slider gripper 24b is pulled down vertically is calculated from the position on the side surface of the directly placed object 101a to be brought into contact with the suction surface 17h of the suction pad 15h and the side surface height of the directly placed object 101a taught in advance. Just do it. In order to detect that the edge formed by the side surface and the bottom surface of the directly placed object 101a and the contact surface 27 at the time of holding the slider gripper 24b are in contact with each other, it is desirable to install a pressure sensor on the contact surface 27 at the time of holding.

  In the above-described embodiment, an example in which the suction pad is moved to change the distance between the suction pad and the protrusion has been described. However, the suction pad is fixed and the protrusion can be moved. It goes without saying that both the suction pad and the protrusion may be movable.

  In the present embodiment, an example of a work robot 10c capable of holding a small article 103 stored in a storage container 102 placed on a storage shelf 100b as shown in FIG. 10 will be described.

  FIG. 11 is an example of a configuration diagram of the work robot 10c in the present embodiment. The work robot 10a according to the first embodiment has one manipulator 12, but the work robot 10c has two manipulators 12x and 12y. These two manipulators 12x and 12y are mounted as being equivalent to the manipulator 12 in the first embodiment. Similar to the manipulator 12 of the work robot 10a in the first embodiment, the gripper 11 and the article measurement sensor 23x are attached to the tip of the manipulator 12x. On the other hand, a small article holding gripper 30 and an article measuring sensor 23y are attached vertically downward to the tip of the manipulator 12y. Other devices are the same as those of the work robot 10a in the first embodiment.

  The small article holding gripper 30 in this embodiment is mounted as having the same function as the suction pad 15. However, the small article holding gripper 30 in the present invention is not limited thereto, and may be any gripper having a function capable of holding the small article 103, and may be, for example, a finger type gripper.

  In the present embodiment, the control unit 14 controls both the manipulators 12x and 12y. Further, the suction force generator 13 can generate suction force independently for the suction pad 15x and the small article holding gripper 30 attached to the gripper 11, and the control unit 14 performs the control thereof. To do. In the present invention, depending on the specifications of the small article holding gripper 30, the control unit 14 may directly control the small article holding gripper 30. The control unit 14 controls both the object measurement sensors 23x and 23y independently. It is assumed that the power supply from the work robot 10a according to the first embodiment to the device additionally changed is performed in the same manner as each device mounted on the work robot 10a according to the first embodiment.

  FIG. 12 is an example of a schematic diagram illustrating a state in which the work robot 10c according to the present embodiment holds the small article 103x present in the storage container 102x. When the work robot 10c according to the present embodiment performs an operation equivalent to the picking work of the directly placed article 101 of the work robot 10a according to the first embodiment with respect to the storage container 102x using the manipulator 12x, the storage container 100b can be used as the storage container. 102x can be pulled out.

  Further, with the storage container 102x pulled out, the small article 103x in the storage container 102x is measured by the article measurement sensor 23y, and the detailed position and orientation of the small article 103x are recognized from the measurement result. Furthermore, the small article holding gripper 30 is brought into contact with the upper surface of the small article 103x in the vertical direction based on the detailed position and posture of the small article 103x, and the suction force generator 13 is used. And the upper surface of the small article 103x are adsorbed. The small article 103x can be taken out from the storage container 102x by pulling the small article holding gripper 30 vertically upward (in a direction perpendicular to the upper surface of the small article 103x) in the adsorbed state.

  According to the configuration of the present embodiment, the small article 103x contained in the storage container 102 such as a cardboard box can be taken out.

  An example of a configuration example based on the embodiment described above is as follows.

<Configuration 1>
A grip for holding the article from the side,
A protrusion disposed on the gravitational direction side with respect to the grip portion, and
It is a work robot characterized by providing.

<Configuration 2>
The grip portion is constituted by a member that expands and contracts,
The work robot according to Configuration 1, wherein a length of the grip portion in a direction in which the grip portion extends and contracts is longer than a length of the projection portion.

<Configuration 3>
The work robot according to Configuration 2, wherein a surface of the protrusion that contacts the article when the grip is held by the grip part is an inclined surface.

<Configuration 4>
When defining the direction of gravity as downward, it has a side projection on the side of the grip part,
The work robot according to Configuration 3, wherein a surface of the side projection that contacts the article when the article is held by the grip portion is an inclined surface.

<Configuration 5>
A plurality of grip portions;
The plurality of grip portions are arranged at least in the direction of gravity,
5. The work robot according to claim 2, 3, or 4, wherein among the plurality of grip portions, the grip portion disposed on the gravity direction side than the other grip portions has a lower expansion / contraction rate. is there.

<Configuration 6>
A moving mechanism for moving at least one position of the grip part or the protrusion part;
A control unit that moves at least one of the grip part and the projection part using the moving mechanism and changes a distance between the grip part and the projection part;
The work robot according to any one of configurations 1 to 5, wherein:

<Configuration 7>
7. The work robot according to any one of configurations 1 to 6, wherein a step including an upper stage and a lower stage having a length longer than the upper stage is formed at a tip of the protrusion.

<Configuration 8>
An adsorbing part that adsorbs to an article;
A manipulator connected to the suction portion and changing the position of the suction portion;
A control unit for controlling the operation of the suction unit and the operation of the manipulator;
A protrusion disposed on the gravitational direction side with respect to the suction portion;
It is a work robot characterized by providing.

<Configuration 9>
A grip portion for holding an article;
A protrusion disposed on the gravitational direction side with respect to the grip portion, and
It is a gripper characterized by comprising.

<Configuration 10>
The grip portion is constituted by a member that expands and contracts,
The gripper according to the ninth aspect, wherein a length of the grip portion in a stretching direction of the grip portion is longer than a length of the projection portion.

<Configuration 11>
The gripper according to Configuration 10, wherein a surface of the protrusion that contacts the article when the article is held by the grip part is an inclined surface.

<Configuration 12>
When defining the direction of gravity as downward, it has a side projection on the side of the grip part,
The gripper according to the eleventh aspect, wherein a surface that contacts the article in the side protrusion when the grip is held by the grip part is an inclined surface.

<Configuration 13>
A plurality of grip portions;
The plurality of grip portions are arranged at least in the direction of gravity,
The gripper according to Configuration 10, 11 or 12, wherein among the plurality of grip portions, the grip portion arranged on the gravity direction side than the other grip portions has a lower expansion / contraction rate. .

<Configuration 14>
A moving mechanism for moving at least one position of the grip part or the protrusion part;
A control unit that moves at least one of the grip part and the projection part using the moving mechanism and changes a distance between the grip part and the projection part;
It is a gripper in any one of the structures 9-13 characterized by having.

<Configuration 15>
15. The gripper according to any one of configurations 9 to 14, wherein a step including an upper stage and a lower stage having a longer length than the upper stage is formed at a tip of the protruding portion.

DESCRIPTION OF SYMBOLS 10 Work robot 11 Gripper 12 Manipulator 13 Suction force generator 14 Control part 15 Suction pad 16 Projection part 17 Suction surface 18 Power supply part 19 Traveling part 20 Tip of projection part 21 Tip of suction pad 22 Ambient environment measurement sensor 23 Article measurement sensor 24 Slider Type Gripper 25 Adsorption Pad Linear Actuator 26 Adsorption Pad Linear Slider 27 Holding Contact Surface 28 Pre-holding Contact Surface 29 Diagonal Lateral Projection 30 Small Article Holding Gripper 100 Storage Shelf 101 Direct Placement Article 102 Storage Container 103 Small Article 200 Conventional suction gripper 300 Overall management terminal 400 Working table

Claims (15)

At least one grip portion for holding the article from the side;
A working robot comprising: a protrusion disposed on a side in a gravitational direction with respect to all of the grip portions , and a projection contacting the side of the article . The grip portion is constituted by a member that expands and contracts,
The length of the grip part in the extending and contracting direction of the grip part is longer than the protrusion part before holding the article, and shorter than the protrusion part after holding the article. The work robot according to 1. The article when the gripping portion is held, the surface in contact with the article in the protrusions claims, characterized in that an inclined surface tip position and tip position of the protrusion of the grip portion is formed 2. The work robot according to 2. When defining the direction of gravity as downward, it has a side projection on the side of the grip part,
The article when the gripping portion is held, the surface in contact with the article in said lateral protrusion, the flush position in contact with the article of the tip position and the protrusion of the grip portion is formed The work robot according to claim 3. A plurality of grip portions;
The plurality of grip portions are arranged at least in the direction of gravity,
Among the plurality of grip portions, the grip portion disposed on the gravity direction side than the other grip portions changes from a state before holding the article to a state after holding the article. The work robot according to claim 2, 3 or 4, wherein the amount of shrinkage of the work robot is small . A moving mechanism for moving a gravitational direction position of at least one of the grip part or the protrusion part;
A control unit that moves at least one of the grip part or the protrusion part using the moving mechanism and changes a distance in the gravitational direction between the grip part and the protrusion part;
The work robot according to claim 1, comprising: The work according to any one of claims 1 to 6, wherein a tip of the protrusion is configured by an upper stage and a lower stage in which the length of the grip portion in the extension / contraction direction is longer than the upper stage. robot. A first gripper having at least one grip part for holding the storage container from the side, and a protrusion disposed on the gravitational direction side with respect to all of the grip parts and in contact with the side of the storage container. A manipulator,
  A second manipulator having a small article holding gripper provided vertically downward;
  A controller that controls the first manipulator and the second manipulator;
A work robot, wherein the small article holding gripper of the second manipulator is taken out of the small article in the storage container in a state where the storage container is pulled out by the first manipulator. At least one grip portion for holding the article from the side ;
Protruding portions that are arranged on the gravitational direction side with respect to all of the grip portions and come into contact with the side of the article ,
A gripper comprising: The grip portion is constituted by a member that expands and contracts,
The length of the grip part in the extending and contracting direction of the grip part is longer than the protrusion part before holding the article, and shorter than the protrusion part after holding the article. The gripper according to 9. The article when the gripping portion is held, the surface in contact with the article in the projections, characterized in <br/> that an inclined surface tip position and tip position of the protrusion of the grip portion is formed The gripper according to claim 10. When defining the direction of gravity as downward, it has a side projection on the side of the grip part,
The article when the gripping portion is held, the surface in contact with the article in said lateral protrusion, the flush position in contact with the article of the tip position and the protrusion of the grip portion is formed The gripper according to claim 10 or 11, wherein A plurality of grip portions;
The plurality of grip portions are arranged at least in the direction of gravity,
Among the plurality of the grip portion, towards the grip portion arranged in the gravity direction than the other of the grip, from the state before holding the article at the time of a state after holding the article The gripper according to claim 10, 11 or 12, wherein the amount of shrinkage is small . A moving mechanism for moving a gravitational direction position of at least one of the grip part or the protrusion part;
A control unit that moves at least one of the grip part or the protrusion part using the moving mechanism and changes a distance in the gravitational direction between the grip part and the protrusion part;
The gripper according to any one of claims 9 to 13, characterized by comprising: 15. The tip of the projection part is configured by an upper stage and a lower stage in which the length of the grip part in the extension / contraction direction is longer than the upper stage. Gripper.

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