Pickup method

Abstract

To realize a pickup work with a simple configuration and suppress an increase in cost for automating the pickup work.SOLUTION: A pickup method which picks up an object having a recess by using a jig held by a robot, includes: an insertion step of the robot inserting the jig into the recess; an end point detection step of detecting an end point of jig insertion into the recess by using a force sensor of the robot; and a pickup step of the robot picking up the object by moving the jig in a reverse direction to an insertion direction of the jig into the recess.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a pickup method. [Background technology]

[0002] Laboratory automation, which uses robots to automate experimental and research tasks that have traditionally been performed by human workers, is known. Examples of tasks that are desirable for automation through lab automation include dispensing tasks, such as collecting a predetermined amount of liquid reagent using a pipette. During dispensing tasks, a task of picking up tips from a tip box is required to attach tips that have been arranged in advance in a tip box to the tip of the pipette. To automate this type of pick-up task, for example, a robot hand, as described in Patent Document 1, is used. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-130116 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the configuration of the robot hand described in Patent Document 1 is complicated, and there is a problem that the cost of automating the pick-up operation increases. Note that this problem is not limited to picking up tips attached to pipettes, but also applies to picking up various objects. [Means for solving the problem]

[0005] (1) According to a first aspect of the present disclosure, there is provided a pickup method for picking up an object having a recess using a jig held by a robot, the pickup method including: an insertion step in which the robot inserts the jig into the recess; an end point detection step in which the robot detects an end point of the insertion of the jig into the recess using a force sensor included in the robot; and a pickup step in which the robot picks up the object by moving the jig in a direction opposite to the insertion direction of the jig into the recess. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is an explanatory diagram showing a schematic configuration of a dispensing device according to an embodiment of the present invention. [Figure 2] 1 is a block diagram showing a schematic configuration of a dispensing device according to an embodiment of the present invention. [Figure 3] 10 is a flowchart showing a procedure for dispensing control in the present embodiment. [Figure 4] 10 is a flowchart showing a procedure for tip mounting control in the present embodiment. [Figure 5] 10A and 10B are explanatory diagrams showing a pickup method in another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] A. Implementation: A-1: Equipment configuration: FIG. 1 is an explanatory diagram showing a schematic configuration of a dispensing apparatus 100 according to this embodiment. FIG. 2 is a block diagram showing a schematic configuration of the dispensing apparatus 100 according to this embodiment. FIG. 1 depicts an X-axis, a Y-axis, and a Z-axis that are perpendicular to each other. The X-axis and Y-axis correspond to the horizontal direction, and the Z-axis corresponds to the vertical direction. The "X-axis direction" refers to a concept that combines the +X direction and the -X direction. Similarly, the "Y-axis direction" refers to a concept that combines the +Y direction and the -Y direction, and the "Z-axis direction" refers to a concept that combines the +Z direction and the -Z direction. In the following description, the +Z direction will also be referred to as "upward" and the -Z direction will also be referred to as "downward."

[0008] The dispensing device 100 is a device for dispensing liquid reagents. More specifically, it is a device for aspirating a liquid reagent L from a reagent bottle B1 containing a type of liquid reagent L specified by a user and dispensing a specified amount of the liquid reagent L into a sample bottle B2. While FIG. 1 illustrates only the reagent bottle B1 containing the liquid reagent L, the dispensing device 100 is not limited to dispensing a single type of reagent; it can also dispense multiple types of liquid reagents from multiple reagent bottles into sample bottle B2. As shown in FIG. 1, the dispensing device 100 includes a pipette 10, a tip 20, a weighing scale 30, a robot 40, a robot control device 50, a camera 60, an input unit 70, a display unit 80, and a control device 90. As shown in FIG. 2, the pipette 10, the weighing scale 30, the robot control device 50, the camera 60, the input unit 70, the display unit 80, and the control device 90 are electrically connected to one another. For convenience of illustration, electrical connections between the display unit 80 and the pipette 10, tip 20, weighing scale 30, and camera 60 are omitted in FIG.

[0009] 1, the pipette 10 is used by attaching a tip 20 to an insertion section 11, which is the distal end of the pipette 10. In this embodiment, the insertion section 11 is formed in a tapered shape such that the outer diameter increases from the distal end, in the -Z direction, toward the proximal end, in the +Z direction. Forming the insertion section 11 in this manner makes it easy to insert the insertion section 11 into the tip 20.

[0010] The pipette 10 aspirates liquid reagent L from a reagent bottle B1 containing a liquid and dispenses the aspirated liquid reagent L into a sample bottle B2. There is no particular limitation on the type of liquid reagent L, as long as it can be aspirated and dispensed by the pipette 10. The pipette 10 can aspirate and dispense a predetermined volume of liquid reagent L by driving a drive unit (not shown). The aspirating and dispensing of liquid reagent L by the pipette 10 is controlled by a control device 90. The pipette 10 is, for example, a micropipette. Any pipette 10 capable of aspirating and dispensing liquid reagent L can be used as the pipette 10. In this embodiment, the tip 20 is formed primarily from resin. Note that the tip 20 is not limited to resin and may be formed from other materials such as glass.

[0011] When the dispensing device 100 dispenses multiple types of liquid reagent L, a tip 20 having a shape corresponding to the viscosity and other properties of the liquid reagent L is attached to the tip of the pipette 10. The pipette 10 is grasped and moved by a robot 40 (described later), and a tip 20 having a shape corresponding to the type of liquid to be dispensed is attached from among multiple tips 20 held in a tip box 22 prepared in advance. The method of attaching the tip 20 to the pipette 10 will be described later.

[0012] The weighing scale 30 measures the weight of the liquid reagent L dispensed into the sample bottle B2 and outputs the measurement result to the control device 90. As shown in FIG. 1, the sample bottle B2 is provided on the weighing scale 30. The sample bottle B2 is, for example, a beaker. The weighing scale 30 is, for example, an electronic balance. The weighing scale 30 is not limited to an electronic balance, and is not particularly limited to any particular type as long as it can measure the weight of the liquid reagent L.

[0013] The robot 40 grasps the pipette 10 and moves the pipette 10 under the control of the robot control device 50 to perform a dispensing operation instructed by the control device 90. The robot 40 has an arm 41, a hand 42, and a force sensor 43. In this embodiment, the robot 40 is configured as a six-axis robot. The hand 42 is attached to the tip of the arm 41 via the force sensor 43. The hand 42 grasps the pipette 10 under the control of the robot control device 50.

[0014] The force sensor 43 detects the force acting on the hand 42 and outputs the detection result to the robot control device 50. In this embodiment, the force sensor 43 detects the magnitude of a force parallel to three detection axes that are orthogonal to each other in a specific sensor coordinate system, and the magnitude of a torque about the three detection axes. The force sensor 43 may be provided at a position other than the tip of the hand 42, for example, at one or more of the multiple joints of the arm 41. The force sensor 43 corresponds to the "force sensor" in this disclosure. The force sensor is not limited to a sensor that can detect forces in multiple axial directions, such as the force sensor 43, and may be, for example, a sensor that can detect forces in a single axial direction.

[0015] In this embodiment, the robot control device 50 can perform impedance control using the detection results of the force sensor 43. "Impedance control" refers to controlling the position and pressing force of the arm 41 and the hand 42 so that the sensor value of the force sensor 43 is equal to a preset value. For example, when controlling an object held by the hand 42 to contact another object with a predetermined pressing force, the robot control device 50 performs position control to move the hand 42 away from the object to be pressed when the sensor value of the force sensor 43 is equal to or greater than a predetermined threshold. On the other hand, the robot control device 50 performs position control to move the hand 42 closer to the object to be pressed when the sensor value is less than the threshold. This impedance control allows the hand 42 to press against the object to be pressed with a predetermined pressing force. In the following description, a function realized by impedance control, which moves the hand 42 closer to the object to be pressed and stops the robot 40 when the force sensor 43 detects a force exceeding a first predetermined threshold, is referred to as a "contact detection function." Furthermore, a function realized by impedance control, in which the hand 42 is pressed against an object to be pressed with a predetermined pressing force and the robot 40 is stopped when a force exceeding a predetermined second threshold is detected by the force sensor 43, is called the "pressing function."

[0016] In this embodiment, the camera 60 is installed in a position of the hand 42 so as not to interfere with an object when the object is grasped by the hand 42. As will be described later, the control device 90 uses the image captured by the camera 60 to correct the robot coordinates of the robot 40.

[0017] The input unit 70 is a device that allows the user to input various pieces of information to the control device 90. The input unit 70 is configured as, for example, a mouse, a touch panel, a keyboard, or the like.

[0018] The display unit 80 displays images captured by the camera 60, input images for the user to input various information to the control device 90, etc. The display unit 80 is configured as, for example, an LCD (Liquid Crystal Display), an organic EL (Electroluminescence) display, an EPD (Electrophoretic Display), a touch panel display, etc.

[0019] As shown in FIG. 2, the control device 90 includes a processor 91, a memory 93, and an interface 94. The control device 90 is electrically connected to the pipette 10, the weighing scale 30, the robot control device 50, the camera 60, the input unit 70, and the display unit 80 via the interface 94, either wired or wirelessly. The memory 93 stores programs and data for the control device 90 to perform various calculations and control processes. The memory 93 also stores information received from the camera 60 and the weighing scale 30, information input by the user via the input unit 70, and the results of calculations performed by the control device 90 according to the various programs. The processor 91 functions as a control unit 92 by executing programs previously stored in the memory 93. The control unit 92 executes various controls to realize dispensing control.

[0020] A-2: Dispensing control: 3 is a flowchart showing the procedure for dispensing control in this embodiment. This control is executed by the control unit 92, for example, when a predetermined start operation is performed on the control unit 90 by the user via the input unit 70. At the start of this control, the hand 42 is not holding the pipette 10. In the following description, to facilitate understanding of the technology, the subject of each control will be described as the "control unit 90," even for controls executed by the control unit 90 via the robot control unit 50.

[0021] In step S10, the control unit 92 controls the robot 40 to move the hand 42 above the tip box 22. The destination coordinates of the hand 42 are set in advance as coordinates for the coordinate correction described below. At this time, the tip box 22 is previously installed in a tip box holder (not shown) provided at a predetermined position. In this embodiment, the tip box holder is formed in a groove shape, and the tip box 22 is positioned by installing the tip box 22 in the tip box holder. Note that, although FIG. 1 illustrates the tips 20 arranged in a row along the X direction in the tip box 22, in reality, they are arranged planarly in the XY plane at a fixed interval from each other. Furthermore, the tips 20 may be arranged in the tip box 22 not only on the XY plane but also at an angle relative to the XY plane.

[0022] In step S20, the control unit 92 controls the camera 60 to photograph the tip box 22.

[0023] In step S30, the control unit 92 uses the captured image of the tip box 22 to calculate the difference between the robot coordinates of the tip 20, which are logically calculated from, for example, the position of the tip 20 at an arbitrary position within the tip box 22 and the position of the tip box holder, and the image coordinates, and calculates the correction amount for the robot coordinates. More specifically, the control unit 92 uses the image of the tip box 22 to detect the outline of the inserted portion 21 of the tip 20 into which the insertion unit 11 is inserted through image analysis and identifies the center coordinates of the inserted portion 21 in the image. The control unit 92 calculates the difference between the identified center coordinates of the inserted portion 21 and the center coordinates logically calculated as described above. In the following description, this difference is also referred to as the "correction amount." Based on the calculated correction amount, the control unit 92 can correct the difference in the robot coordinates of the inserted portion 21, which may occur depending on how the tip box 22 is placed. The inserted portion 21 corresponds to the "recess" in this disclosure. Note that the method of calculating the correction amount using an image has been described above for a single tip, but it may also be performed for multiple tips. Furthermore, the method for identifying the center coordinates of the inserted portion 21 is not limited to the above-described embodiment, and any known method may be used.

[0024] In step S40, the control unit 92 controls the robot 40 to grip the pipette 10. More specifically, the control unit 92 controls the robot 40 to move the hand 42 to a pipette rack (not shown) in which the pipettes 10 have been placed in advance, and grip the pipette 10.

[0025] In step S50, the control unit 92 executes tip attachment control and attaches the tip 20 to the insertion unit 11. The procedure for tip attachment control in this embodiment will be described later.

[0026] In step S60, the control unit 92 controls the pipette 10 to aspirate liquid reagent L from reagent bottle B1. In step S70, the control unit 92 controls the pipette 10 to dispense liquid reagent L into sample bottle B2. The type of liquid reagent L to be aspirated in step S50 and the amount of liquid reagent L to be dispensed in step S60 are input in advance by the user and stored in memory 93. Note that the operations of the robot 40, such as inserting and retracting the pipette 10 into reagent bottle B1 or sample bottle B2, performed in steps S60 and S70 are similar to operations performed in general dispensing control, and therefore detailed description thereof will be omitted.

[0027] In step S80, the control unit 92 removes the tip 20 attached to the insertion unit 11. The control for removing the tip 20 is similar to the operation performed in general dispensing control, and therefore a detailed description thereof will be omitted.

[0028] In step S90, the control unit 92 determines whether or not there is a next dispensing. If it is determined that there is a next dispensing (step S90: Yes), the control unit 92 executes the above-mentioned step S40 again and attaches a new tip 20 to the insertion unit 11. If it is determined that there is no next dispensing (step S90: No), the control unit 92 ends dispensing control.

[0029] The tip attachment control described above will now be described. FIG. 4 is a flowchart showing the steps of the tip attachment control in this embodiment. By executing the tip attachment control, the control device 90 attaches the tip 20 to the insertion section 11 and picks up the tip 20 from the tip box 22. The pipette 10 corresponds to the "jig" in this disclosure, and the tip 20 corresponds to the "object" in this disclosure. Furthermore, the method of picking up the tip 20 realized by the tip attachment control corresponds to the "pickup method" in this disclosure.

[0030] In step S110, the control unit 92 controls the robot 40 to move the insertion unit 11 to the first target coordinates. In this embodiment, the first target coordinates are coordinates located directly above the central coordinates obtained by applying a correction amount to coordinates logically calculated from the position of the tip box holder of the inserted portion 21 of the tip 20 to be attached, and are coordinates located several tens of centimeters above the +Z side end of the tip 20 in the +Z direction.

[0031] In step S120, the control unit 92 controls the robot 40 to move the insertion unit 11 to the second target coordinates. In this embodiment, the second target coordinates are coordinates located directly above the center coordinates obtained by applying a correction amount to coordinates logically calculated from the position of the tip box holder of the inserted portion 21 of the tip 20 to be attached, and are located approximately 1 cm above the +Z side end of the tip 20 in the +Z direction.

[0032] In step S130, the control unit 92 controls the robot 40 to use the contact detection function described above to start the descent of the insertion unit 11. Since the movement speed of the robot 40 is limited while the contact detection function is being used, by starting to use the contact detection function after moving the robot 40 to the second target coordinates, the time required for tip attachment control can be shortened compared to a mode in which the contact detection function is started to be used at the first target coordinates.

[0033] In step S140, the control device 90 determines whether the pressing force detected by the force sensor 43 is less than 1N. If the pressing force is 1N or greater, the control device 90 determines that the insertion portion 11 has contacted the insertion receiving portion 21. By contacting the insertion portion 11 with the insertion receiving portion 21, the tip of the insertion portion 11 is inserted into the insertion receiving portion 21. Here, "1N" corresponds to the "first threshold" in the contact detection function described above. Note that the first threshold may be set to an appropriate value depending on the shape and material of the tip 20. In this embodiment, the force sensor 43 is used to detect the contact of the insertion portion 11 with the insertion receiving portion 21. Therefore, even when picking up an item such as the tip 20 of this embodiment, which has different shapes depending on the type and is formed primarily from resin and therefore prone to dimensional variation, the insertion portion 11 can be brought into contact with the insertion receiving portion 21 without requiring detailed instruction to the robot 40. Steps S130 and S140 correspond to the "insertion step" in this disclosure.

[0034] If it is determined that the pressing force is less than 1 N (step S140: Yes), the control device 90 determines that the insertion portion 11 has not yet contacted the inserted portion 21, and continues the descent of the insertion portion 11, in other words, the approach of the insertion portion 11 to the inserted portion 21. If it is determined that the pressing force is 1 N or more (step S140: No), in step S150, the control device 90 uses the above-mentioned pushing function to start the descent of the insertion portion 11.

[0035] In step S160, the control device 90 determines whether the pressing force detected by the force sensor 43 is less than 20 N. When the pressing force is 20 N or greater, the control device 90 detects that the insertion portion 11 has reached the end point of insertion into the insertion portion 21. This "20 N" corresponds to the "second threshold" in the contact detection function described above. The second threshold may be set to any appropriate value depending on the shape and material of the tip 20. In this embodiment, the force sensor 43 is used to detect that the insertion portion 11 has reached the end point of insertion into the insertion portion 21. Therefore, even when picking up an item that has different shapes depending on the type, such as the tip 20 of this embodiment, and that has different distances from the start of insertion to the end point, the insertion portion 11 can be inserted into the insertion portion 21 to the end point without requiring detailed instruction to the robot 40. Steps S150 and S160 correspond to the "end point detection step" in this disclosure.

[0036] If it is determined that the pressing force is less than 20 N (step S160: Yes), the control device 90 determines that the insertion portion 11 has not been sufficiently pushed into the inserted portion 21, and continues to lower the insertion portion 11, in other words, to push the insertion portion 11 into the inserted portion 21. If it is determined that the pressing force is 20 N or more (step S160: No), in step S170, the control device 90 determines that the insertion portion 11 has been sufficiently inserted into the inserted portion 21, and stops pushing the insertion portion 11 into the tip 20.

[0037] In step S180, the control device 90 moves the pipette 10 upward in the +Z direction, in other words, moves the pipette 10 in the opposite direction to the insertion direction of the insertion portion 11 into the insertion portion 21. When the insertion portion 11 is fully pressed into the insertion portion 21, the tip 20 is held in the pipette 10 by the frictional force between the insertion portion 11 and the insertion portion 21. Therefore, by lifting the pipette 10, the tip 20 is picked up from the tip box 22. Step S180 corresponds to the "pickup step" in this disclosure. This completes the tip attachment control by the control unit 92.

[0038] According to the tip attachment control executed in the dispensing device 100 of the embodiment described above, the force sensor 43 is used to detect the end point of the insertion of the insertion portion 11 into the insertion receiving portion 21, and when the insertion portion 11 is inserted into the insertion receiving portion 21 to the end point, the robot 40 moves the pipette 10 in the +Z direction to pick up the tip 20. This allows the tip 20 to be picked up from the tip box 22 with a simple configuration, thereby suppressing an increase in cost for automating the pick-up operation. In addition, because the force sensor 43 is used to detect that the insertion portion 11 has reached the end point of its insertion into the insertion receiving portion 21, even when picking up an item whose shape varies depending on the type and whose distance from the start of insertion to the end point varies, such as the tip 20 of this embodiment, the insertion portion 11 can be inserted into the insertion receiving portion 21 to the end point without requiring detailed instruction to the robot 40.

[0039] In addition, the insertion portion 11 is formed in a tapered shape with an outer diameter that increases from the tip side to the base end side, making it easier to guide the insertion portion 11 into the inserted portion 21 and easier to insert into the inserted portion 21.

[0040] Furthermore, even if the chip 20 to be picked up is made primarily of resin and is prone to dimensional variations, the pick-up operation can be performed with a simple configuration, and the increase in costs for automating the pick-up operation can be suppressed.

[0041] Furthermore, by using the pipette 10 as a jig, the pick-up operation can be performed with a simple configuration, and an increase in the cost for automating the pick-up operation can be suppressed.

[0042] B. Other Embodiments: (B1) In the above embodiment, the insertion portion 11 is formed in a tapered shape, but the present disclosure is not limited to this. The insertion portion 11 may be formed in a cylindrical shape with a constant outer diameter from the distal end to the proximal end. Even with this configuration, when the insertion portion 11 is inserted all the way into the insertion portion 21, the robot 40 can move the pipette 10 in the +Z direction to pick up the tip 20.

[0043] (B2) In the above embodiment, the pickup method is realized as a method for picking up the tip 20 using the pipette 10, but the present disclosure is not limited thereto. FIG. 5 is an explanatory diagram showing a pickup method in another embodiment. The pickup method of the present disclosure may be realized as a method for picking up a gear member 20B using a jig 10B, as shown in FIG. 5. Note that FIG. 5 does not illustrate a robot or the like that holds the jig 10B. Even with this configuration, as shown in FIG. 5, the gear member 20B can be picked up by inserting the insertion portion 11B, which is the tip portion of the jig 10B, all the way into the hole 21B of the gear member 20B and then moving the jig 10B in the direction opposite to the insertion direction, thereby easily picking up the gear member 20B. Note that the hole 21B does not have to be completely through. The hole 21B corresponds to the "recess" in the present disclosure. As such, the pickup method of the present disclosure is not limited to picking up the tip 20 using the pipette 10, but can be applied to picking up any object having a recess.

[0044] The pickup method may also be implemented using a jig and an object formed to have a snap-fit structure that allows them to engage with each other through elastic deformation. In this form, as in the above embodiment, the object is inserted into the jig to the end point and engaged, and then the object is picked up by moving the jig in the direction opposite to the insertion direction, making it possible to pick up the object in a simple manner.

[0045] C. Other forms: The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features of the embodiments corresponding to the technical features in each aspect described below can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0046] (1) According to a first aspect of the present disclosure, there is provided a pickup method for picking up an object having a recess using a jig held by a robot. This pickup method includes an insertion step in which the robot inserts the jig into the recess; an end point detection step in which the robot detects an end point of the insertion of the jig into the recess using a force sensor included in the robot; and a pickup step in which the robot picks up the object by moving the jig in a direction opposite to the insertion direction of the jig into the recess. According to this aspect, the force sensor is used to detect the end point of the insertion of the jig into the recess, and the robot picks up the object by moving the jig in the direction opposite to the insertion direction. This allows the object pickup operation to be achieved with a simple configuration, and reduces the cost increase associated with automating the pickup operation.

[0047] (2) In the above embodiment, the insertion portion of the jig, which is the portion inserted into the recess, may be tapered so that the outer diameter increases from the distal end to the proximal end of the jig. According to this embodiment, the insertion portion is tapered so that the outer diameter increases from the distal end to the proximal end, which makes it easy to insert the insertion portion into the recess.

[0048] (3) In the above-described embodiment, the object may be made primarily of resin. According to this embodiment, even if the object to be picked up is made primarily of resin and has large dimensional variations, the pickup operation can be realized with a simple configuration, and an increase in costs for automating the pickup operation can be suppressed.

[0049] (4) In the above-described embodiment, the jig may be a pipette. According to this embodiment, the pipette can be used as the jig, allowing the pick-up operation to be performed with a simple configuration, and reducing the cost of automating the pick-up operation. [Explanation of symbols]

[0050] 10...pipette, 10B...jig, 11, 11B...insertion part, 20...tip, 20B...gear member, 21...inserted part, 21B...hole, 22...tip box, 30...weighing scale, 40...robot, 41...arm, 42...hand, 43...force sensor, 50...robot control device, 60...camera, 70...input part, 80...display part, 90...control device, 91...processor, 92...control part, 93...memory, 94...interface, 100...dispensing device, B1...reagent bottle, B2...sample bottle, L...liquid reagent

Claims

1. A pickup method for picking up an object having a recess by using a jig held by a robot, comprising: an insertion step in which the robot inserts the jig into the recess; an end point detection step of detecting an end point of insertion of the jig into the recess by using a force sensor included in the robot; a pick-up step in which the robot picks up the object by moving the jig in a direction opposite to an insertion direction of the jig into the recess; Including, Pickup method.

2. The pickup method according to claim 1, An insertion portion of the jig, which is a portion to be inserted into the recess, is formed in a tapered shape such that the outer diameter increases from the distal end side to the proximal end side of the jig. Pickup method.

3. The pickup method according to claim 1 or 2, The object is made primarily of resin. Pickup method.

4. The pickup method according to claim 1 or 2, The jig is a pipette. Pickup method.

Images