JP2006068893A - Gripping device of fragile product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a robot hand for gripping and/or cutting a fragile product in a narrower work space where obstacles are closed up or a space like in vitro. <P>SOLUTION: A robot hand is provided with a pair of gripping claws, a gripping actuator, and a gripping force transfer system for connecting the gripping actuator and the gripping claw. A part or the whole part of the gripping force transfer system is formed of a material having elastic characteristics. Thus, the robot hand can grip a fragile product, while causing a deflection in the gripping force transfer system and/or gripping claws by a drive of the gripping actuator. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus for grasping a fragile object in a narrow working space, and in particular, to cultivate aseptic clonal seedlings, to automate a transplanting process in which aseptic seedlings cultured in vitro are separated and implanted in a rooting container. It relates to a robot hand that enables it.

In addition to the production of seedlings and cuttings seedlings that have been used so far in the production of horticultural crops and tree seedlings in recent years, micropropagation allows mass propagation of sterilized clones of excellent individuals and rooting them into seedling products Has become widespread.
As a general technique, a growing tissue point is cut out from a plant individual in a sterile environment, provided with a culture environment in vitro (in a sterile transparent container), grown into multi-buds, and further proliferated in large quantities by subculture. After each grown bud was grown to an optimal size in vitro, the shoot was again separated in a sterile environment, transferred to a container for rooting, cultured again in vitro, and germinated clonal seedlings after completion of rooting. There is something to be a product. This is a technique that utilizes the fact that an infected seedling does not invade the growth point tissue that is the source of plant growth.

  As described above, the production process in the plant factory mainly includes a transplanting process for planting separated seedlings in vitro and a culture process in vitro. The seedling culture process is almost automated, but the transplanting process is still carried out by hand, and the need for mechanization has increased due to the need to secure a large number of excellent workers during the busy season. Yes.

  However, the young buds are soft and fragile, and when an excessive grip force is applied, there is a problem that the stem duct is broken and the subsequent growth does not proceed smoothly. For this reason, in order to automatically transplant shoots, it is indispensable to control a slight grip force.

  As a seedling division transplantation device, a device for recognizing the shape of a seedling by a recognition device using laser light and guiding a gripping mechanism and a cutting mechanism to a predetermined height position of the seedling based on the recognition result is proposed. (Patent Documents 1 and 2).

  As a handling device for fragile objects, a leaf spring for gripping the fragile object, a cushion material provided on the leaf spring to weaken an impact at the time of gripping, an actuator for opening and closing the leaf spring in parallel, and the actuator An apparatus having a mechanism for moving the device has been proposed (Patent Document 3).

In addition, the transplanted seedling transplanting system scans the stem shape of the seedlings on the open tray with a slit laser beam and PSD sensor, controls the gripping force by feedback with a strain sensor, and automatically produces the inserted seedlings with a manipulator. It has been proposed (Non-Patent Documents 1 and 2).
JP-A-3-228607 JP-A-5-3707 JP 7-276281 A M. Takatsuji, Handbook of Plant Factory, Tokai University Press, pp. 123 {159, 1997. Tokai University Press: “Plant Factory Handbook”, Tokai University Press (1997), pp123-159 Takayama Kosaku CMC Publishing Seedling Production System (1992 First Edition 2002 Popular Edition pp180)

Most of the costs associated with growing seedlings are labor costs, and mechanization can greatly reduce seedling production costs. In addition, in manual work, it becomes necessary to discard seedlings due to quality deterioration due to virus contamination, which also leads to an increase in production costs.
As described above, since the seedling culture process is almost automated, the present invention has an object to be solved by automating the in vitro transplantation process to the culture container. FIG. 16 is a flowchart of a clone seedling growing process. The present invention aims to automate the processes of STEPs 13 to 15, which are the transplanting process to a culture container in vitro.

  The devices of Patent Documents 1 and 2 are based on the premise of working in an open tray, and cannot be operated in a working environment where seedlings in a container are dense. In addition, since the speed reduction mechanism is not provided, it is difficult to make a weak adjustment of the force for gripping the stem, and there is a risk of damaging the stem when used in the planting process.

  In the apparatus of Patent Document 3, an object having an obstacle (leave) on the upper part of a gripping part such as a plant cannot be gripped. In order to work in aseptic conditions, it is preferable to periodically remove the gripping part of the device and its nearby parts and sterilize with high-temperature high-pressure steam, etc., but on the structure using a cushioning material, It was difficult to sterilize.

  Further, in the above devices, when an aseptic clonal seedling is produced, it is not possible to work in an in vitro culture container. Therefore, a clean room is necessary to make it aseptic. For this reason, there is a problem that a large work space and expensive equipment are required, and a large cost is required.

  In view of the above problems, an object of the present invention is to provide a robot hand for grasping and / or cutting a fragile object in a place where obstacles are densely packed or in a narrow work space such as in vitro.

  In order to solve the above-mentioned problems, the present invention relates to a transmission generated by a rotational force from an actuator in an apparatus having an actuator for driving a gripping part and a transmission system made of a material having at least part or all of an elastic property. It is possible to obtain the optimum gripping force by utilizing the elastic deformation of the system.

By setting the gripping portion to include a pair of gripping claws and a pair of cutting blades, the lower portion can be cut while gripping the stem, so that a gripping device suitable for the separation step can be provided.
In addition, since the gripping portion includes the upper pair of gripping claws and the lower pair of gripping claws, the gripping position of the other gripping claws can be changed while gripping the stem with the one gripping claws. A gripping device suitable for the process can be provided.

  Furthermore, since the power from the actuator is transmitted by a tension wire or a torque transmission wire, it is no longer necessary to provide the actuator in the hand portion, so that the gripping device can be reduced in size. In this configuration, it is possible to control the gripping claw force more finely by providing a speed reduction mechanism.

That is, the gist of the present invention is the following robot hands (1) to (9).
(1) A pair of gripping claws, a gripping actuator, and a gripping force transmission system that couples the gripping actuator and the gripping claws, and a part or all of the gripping force transmission system is made of a material having elastic characteristics. A robot hand that grips a fragile object while causing the gripping force transmission system and / or the gripping claw to bend by driving the gripping actuator.
(2) Furthermore, it is provided with a plurality of cutting blades, a cutting actuator, and a cutting force transmission system for connecting the cutting actuator and the cutting blade, and the cutting blades are brought into contact with each other by driving the cutting actuator. (1) Robot hand which cuts.
(3) The robot hand according to either (1) or (2), wherein the pair of gripping claws are reverse tweezers set in advance so as to give an optimal gripping force.
(4) The gripping actuator is arranged outside the robot hand, and the gripping force transmission system is configured to transmit the driving of the gripping actuator to the gripping claws by twisting a torque transmission wire. The robot hand of any one of (3).
(5) The gripping actuator is arranged outside the robot hand, the gripping force transmission system is composed of a tension wire that passes through the outer tube, and the pair of gripping claws are opened and closed by the tension wire. The robot hand according to any one of (1) to (3).
(6) The robot hand according to any one of (1) to (5), further including a speed reduction mechanism that sets a stroke or a rotation angle transmitted from the gripping actuator to a gripping claw and a driving force of 1 / n.
(7) The robot hand according to any one of (1) to (6), wherein the gripping claws are movable up and down by a certain width.
(8) The robot hand according to any one of (1) to (7), wherein the gripping claws are detachable.
(9) The robot hand according to any one of (1) to (8), wherein the robot hand includes a plurality of the pair of gripping claws.

  According to the present invention, since the minute gripping force control necessary for automatically transplanting a plant can be easily performed, not only the separation process is automated, but also the delicate gripping force adjustment in the implantation process can be performed. Therefore, there is no possibility of giving excessive gripping force to the plant, and it is possible to prevent the occurrence of growth failure due to damage to the stem conduit at the time of planting.

  In addition, it is possible to remove the gripping portion and sterilize with high-temperature and high-pressure steam or the like in terms of structure, and the maintenance is excellent.

In addition, it is possible to automate the work of gripping a fragile object in a narrow work space such as a place where obstacles are concentrated or an in vitro environment.
In addition, if a configuration using a torque rope or the like is adopted, it is possible to reduce the size of the apparatus that tends to be enlarged for delicate control. That is, since the hand portion can be made light and compact, it is not necessary to provide a clean room, and work in a clean bench is possible, so that the production cost of cloned seedlings can also be reduced in terms of equipment.

The 1st form of this invention is a holding | grip apparatus which controls the action | operation of a holding nail with a rod.
FIG. 1 (a) shows a state in which the gripping part 6 is in contact with a plant shoot. The gripping portion 6 is opened and closed when the drive of the actuator is transmitted to the rod 7 that passes through the sheath tube 5. The rod 7 can be moved up and down by the actuator moving directly, and can be positioned at an optimum place for gripping.
FIG. 1 (b) shows a state in which the gripping portion 6 grips the plant shoots. The rod 7 closes the gripping claws as the actuator rotates. In this state, sufficient gripping force for gripping the young shoots is not given.
FIG. 1 (c) shows a state where a sufficient gripping force is applied to the grip portion 6. When a sufficient gripping force is applied to grip the bud, the rod 7 made of a material having elastic characteristics is twisted and bent, and the bud can be gripped without damaging the bud. It is.
When working in a narrow space, it is easy to allow the gripping claws to enter the work place by providing an angle to the gripping claws. For example, preferable angles of the gripping claw and the rod include 30 °, 45 °, 60 °, 90 °, 120 °, and 135 °.
In order to measure the distance from the plant gripping position to the hand gripping position when recognizing the shape of the plant, the gripping nail is preferably composed of a material that does not cause reflection on the surface of the hand, and ceramic is a preferable material. Can be mentioned.

The second aspect of the present invention is a gripping device that controls the operation of the gripping claws using a torque transmission wire (including an outer tube) or the like.
For example, as shown in FIG. 17, in the configuration having a pair of sheath tubes 5 and a pair of gripping claws 61a and 61b as in the first embodiment, the drive transmission from the actuator to the gripping claws is a pair of torque ropes. 76. By not using a rod for transmitting the driving force, the actuator can be provided outside the gripping device, so that the gripping device can be downsized.

  The part that is not directly connected to the gripping claw is driven to rotate the upper gear with a normal tension wire, and the torque is transmitted from the center of the gear on the side of the gripping claw that engages with this. Good to communicate. The significance of such a configuration is that torque may be generated due to a change in the relative position with an externally arranged actuator due to the operation of the articulated robot, which may cause unnecessary rotational movement of the hand. is there. However, when the operation is performed in a positional relationship in which rotation is not applied by the movement of the articulated robot, it is not necessary to adopt such a configuration, and the drive of the motor may be directly transmitted by a torque transmission wire. For example, it is conceivable that each torque transmission wire is coupled to the center of a double-shaft type motor or a pair of opposed gears of the same number, and the gear is driven by the motor.

  Although the above is a structure suitable for an implantation process, it can also be utilized in a separation process by providing a pair of cutting blades.

  Hereinafter, embodiments of the present invention will be described by way of examples, but the present invention is not limited to the following examples.

1. Structure As shown in FIG. 2, the hand unit of the present embodiment includes a support frame 2, actuators 31 to 33 arranged in the support frame 2, a controller (not shown) for controlling the actuator, and the support It is comprised by the sheath part 5 attached to the frame 2, and the holding part 61 and the cutting | disconnection part 62 which are act | operated by the three rods 7a-7c which pass the inside of this sheath pipe 5 axially. Each component will be described in detail below.

(1) Support frame 2
The support frame 2 is composed of upper and lower substrates 21 and 22 and four support pillars 23 that hold the substrates at a predetermined interval. On the upper surface of the upper substrate 21, a hand is attached to an external manipulator. And a through hole for inserting the rod 7 is formed in the lower substrate 22. Three actuators 31 to 33 are attached between the upper and lower substrates 21 and 22.

(2) Holding part 61 and cutting part 62
As shown in FIG. 3, at the tip of the hand part, there are a gripping part 61 composed of a pair of gripping claws and a cutting part 62 composed of a pair of cutting blades at the lower stage.
A material 65 having elastic properties constituting the rod 7 a is connected to the gripping claw 61 a and opens and closes by driving the actuator 32. A material 65 having elastic properties constituting the rod 7b is connected to the grip claw 61b. The grip 61 can be moved up and down by driving the actuator 31.
The cutting part is composed of a cutting blade 62a that opens and closes by driving of the actuator 33 and a fixed cutting blade 62b. The rod 7c that transmits the drive of the actuator 33 to the cutting blade 62a has increased rigidity so that it can withstand a moment during cutting.
When working in a narrow space, it is easy to allow the gripping claws to enter the work place by providing an angle to the gripping claws. For example, preferable angles of the gripping claw and the rod include 30 °, 45 °, 60 °, 90 °, 120 °, and 135 °.
Note that the gripping claws and / or cutting blades may be rotated together, or when one of them is not rotated, the other may be a sheath-and-tube type.

(3) Actuators 31-33
In this embodiment, step motors are employed for the actuators 31 to 33. As shown in FIG. 4, the gripper claws 61 a and 61 b are driven by the actuators 31 and 32, and the cutting blade 62 a is driven by the actuator 33. When the drive shaft of the actuator 31 moves linearly in the same axial direction as the rods 7a and 7b, force is transmitted from the support plate 35 to 7a and 7b, and the gripping portion 61 moves up and down. The drive shaft of the actuator 32 rotates, whereby the gripping claw 61a opens and closes. The drive shaft of the actuator 33 rotates, whereby the cutting blade 62a opens and closes.

(4) Sheath tube 5
A sheath tube 5 is attached to the lower surface of the substrate 22 at the center so as to match the through hole. A rod support plate provided with a hole through which the gripping rods 7a and 7b pass and a holding hole for rotatably holding the cutting rod 7c is attached to the upper portion of the sheath tube 5.
In addition, a slit that allows the gripping claws and the cutting blade to protrude outward and allows the gripping claws to move up and down is formed at the lower end of the sheath tube 5. The lower end opening of the sheath tube 5 is sealed with a detachable stopper to prevent the rod mounted in the sheath tube from falling off. The stopper should be rounded at the end to make it slippery.
In order to work in a narrow place, the diameter of the sheath tube should be narrow. In a conventional apparatus having only 3 to 4 cm at the cutting portion, it is difficult to perform separation and planting work in an environment where plant seedlings are adjacent as well as in vitro work. In the apparatus of the present embodiment, the diameter of the sheath tube is about 8 mm, and the length of each nail blade is about 6 mm. When the length of the blade or the gripping claw is long, the penetrability of the densely seedlings in the container into the stem portion is deteriorated. When the length is short, the leaf and the sheath tube come into contact with the stem and the hand and the cutter do not reach the stem. Therefore, the length of the nail blade is preferably set to be the same as the shape of the target plant, particularly the length of the leaf.

As shown in FIG. 5, the sheath tube 5 is divided at an intermediate portion, and can be attached and detached with a fitting portion 8 having an uneven shape. In the bioseedling separation / planting operation, it is a major premise that the tip can be sterilized and sterilized, so it is significant that the tip can be removed.
Note that it is preferable to cover the periphery of the fitting portion with a pipe in order to facilitate attachment and detachment at the fitting portion 8 and prevent the fitting from being removed by the driving torque.

(5) Rods 7a-7c
There are rods 7a, 7b that transmit the force of the actuator to a pair of gripping claws 61a, 61b at the tip of the sheath tube 5, and a cutting rod 7c that transmits the force of the actuator to the cutting blade 62a at the tip of the sheath tube 5. The gripping rods 7a and 7b are held by a support plate 35 that moves up and down by an actuator 31, and the gripping portion 61 can move up and down. The gripping rod 7b can be rotated by the actuator 32, whereby the gripping claw 61a is opened and closed. The cutting rod 7c can also be rotated by the actuator 33, whereby the cutting blade 62a is opened and closed, and the object is cut in cooperation with the fixed blade 61b. An arm having an engaging portion that engages with a slit of a rotating arm attached to the actuators 32 and 33 is formed in a portion of the gripping rods 7a and 7b and the cutting rod 7c protruding above the rod support plate. The rotation of each actuator is transmitted to each rod.
(6) Usage Mode As shown in FIG. 6, the hand unit according to the present embodiment is used by being connected to an external manipulator.

2. Operation First, as shown in FIG. 7, the hand portion is moved in the X, Y, and Z directions, and the hand tip portion is moved in the vicinity of the object to be cut (STEP 1). At this time, if the position of the object is known in advance, the position measurement of the object is not necessary. When the tip of the hand faces the object, the actuators 32 and 33 are rotated by a signal from the controller, and the gripping claws 61a and the cutting blade 62b are opened (STEP 2). The actuator 31 is driven to adjust the height of the gripping portion 61, and the hand portion is moved to a gripping position where the gripping claws 61a and / or 61b touch the object (STEP 3). The actuators 32 and 33 are rotated in the reverse direction and are closed until the gripping claws 61a and the cutting blade 62a are in contact with the object (STEP 4). The actuators 32 and 33 are rotated in reverse so as to grip the object with an optimum gripping force by a calculation method described later (STEP 5). The actuator 31 is rotated to raise the grip 61, and after separating the cut object, the hand is moved (STEP 6).

3. Calculation of Optimal Gripping Force FIG. 8 shows a position change model of an object and a gripping nail when a gripping force is applied stepwise to the gripping nail. In the gripping device of the present invention, since a part of the rod is made of a material having elastic characteristics, the gripping force is increased and the positions of the left and right gripping claws are also moved. Optimum gripping force can be obtained by giving a rotation angle to the rod so that the torsion of the material having the left and right elastic characteristics is balanced and the object to be gripped is not damaged.

The deformation model in the force transmission path in the gripping claw 73 is as shown in FIG. The elastic deformation amount δ of the material having the elastic characteristics when the gripping force F set here is applied is calculated from the equations 1 and 2. The optimum twist angle θ corresponding to this can be calculated from Equation 3, and the optimum gripping force for gripping the fragile object 74 by giving this rotation to the control lever 71 from the state where the gripping claw is in contact with the object is obtained. Obtainable.
F: gripping force, δ: elastic deformation amount (deflection amount), E: longitudinal elastic modulus, l: material length having elastic properties, I: secondary moment of section
d: Diameter of the material having elastic characteristics
θ: optimum twist angle, L: minimum distance from the center line of the rod axis to the object gripping position

For example, if it is desired to grip 35 grams, the driving stroke θ is 1 = 35, d = 0.9, and L = 6.
δ = (0.035 ・ 35 ³ ) / (3 ・ 19900 ・ (π ・ 0.9 ⁴ /64))=0.78mm
θ = Sin ⁻¹ (δ / L) = 7.47 °.

Since the setting range is ± 5g, the stroke at the upper and lower limits is 40 grams.
δ = (0.04 ・ 35 ³ ) / (3 ・ 19900 ・ (π ・ 0.9 ⁴ /64))=0.89mm
θ = Sin ⁻¹ (δ / L) = 8.56 °.

Similarly, the upper limit stroke is 30 grams,
δ = (0.03 ・ 35 ³ ) / (3 ・ 19900 ・ (π ・ 0.9 ⁴ /64))=0.67mm
θ = Sin ⁻¹ (δ / L) = 6.41 °.
The minimum control angle of the step motor is 0.5 °, and it is possible to perform control corresponding to a finer positioning request by adding a reduction gear. Note that the above calculation formula is an example, and it is preferable to calculate the rotation angle of the motor that generates a deformation amount to give a necessary gripping force by using an elastic calculation formula based on the hook rule according to the shape of the hand.

4). Measurement of seedling strength In order to calculate the optimum gripping force range of the apparatus according to the present invention, seedling strength experiments were conducted using eucalyptus seedlings. The range of the optimum gripping force is calculated by gradually applying a force to the stem of the bud and measuring the force at which the bud diameter and the water-induced discoloration due to cell destruction occur.
FIG. 10 shows the experimental results of Eucalyptus buds, where the circled portion indicates the load at which the seedling was damaged. From this result, the required specifications for grip force control are as shown in the following table.

5. Operational experiment When 20 eucalyptus buds with diameters of i) 0.5 to 0.9 mm and ii) 1 to 1.5 mm were implanted automatically as described in the table below, the frequency of discoloration was 0 and It was possible to achieve automatic planting of clone seedlings that were difficult to control.

FIG. 11 shows an example of a hand unit having two pairs of gripping claws. In the hand portion of the present embodiment, a pair of gripping claws 63a and 63b are disposed at the upper end of the tip, and a pair of gripping claws 64a and 64b are disposed at the lower stage. These four claws are able to perform more stable gripping as compared with the first embodiment when the drive from the actuator is transmitted by the material 65 having elastic characteristics and the gripping claws 63a and 64a are opened and closed. The pair of gripping claws 63a and 63b can be lifted and lowered by driving from the actuator as in the first embodiment.
Further, in the case of an implanting hand, not only the upper gripping part but also the lower gripping part may be moved up and down. If the `` distance from the gripping claw to the lowest end of the plant stem '' is particularly fragile, there is a risk of buckling due to the reaction force from the culture medium at the time of implantation, but the above distance can be shortened by moving the lower gripping part up and down. Then it can be planted in several times. That is, in order to ensure a specified amount of planting even if the distance is shortened, after planting with the upper and lower gripping parts gripped, the lower gripping claws are released and the lower After the gripping claw is moved up, the operation of holding again with the lower gripping claw and implanting can be repeated. Thereby, the damage of the plant in the planting operation can be prevented.

FIG. 12 and FIG. 13 show an embodiment of the hand portion in which the grip portion is a notch of the sheath tube. In the present embodiment, the object is positioned in the notch 68, and the cutting blade 66 moves up and down to separate the object, and the object is gripped by the gripping shaft 67. It can be said that since the gripping part fits inside the sheath tube, it is a form suitable for work in a narrower space.
Note that the cutting blade 66 may be a hollow one that passes through the inside of the shaft 67 or may cover the shaft 67 slightly larger than the outer periphery of the shaft 67.

  An elastic body using a torsion spring may be disposed in the vicinity of the drive unit without using a material that uses elastic characteristics for the rod. As shown in FIG. 15, one of the torsion springs 75 is joined to the rod 7 and the other is joined to the control lever 71, so that the rod 7 can be rotated. When the gripping claw contacts the object and further rotates, the torsion spring is deformed, and as a result, an optimal gripping force is generated in the gripping portion.

  For example, in order to obtain a preset gripping force F, the twist angle φ of the torsion spring from the point where a necessary gripping claw comes into contact can be obtained by the following equation.

M ＝ F ・ a
M: Moment acting on torsion spring, a: Length from center to gripping claw

φ = ML / EI = 64MDN / Ed ⁴
L: Effective length of the torsion spring, E: Longitudinal elastic modulus, D: Coil average diameter, N: Number of turns, d: Wire diameter, I: Cross section secondary moment

As shown in FIGS. 18 and 19, the hand portion of the present embodiment has a configuration using four rods that pass through the inside of the sheath tube 5 and torque transmission wires connected thereto. The sheath tube 5 is provided with four shaft holes 51 for allowing the rod to pass therethrough (see the upper diagram in FIG. 22). By connecting each rod and the torque transmission wire, it is possible to prevent interference with the arm or the like and to make it compact.
Each rod passes through the shaft through hole 51, the lower end is connected to the grip portion 6, and the upper end is connected to the torque transmission wire. Since the torsional elastic characteristics differ depending on the direction of the torque transmission wire, in order to maintain a uniform force balance at the assumed gripping position, the length distribution is determined while balancing while assembling and is connected through the center of the driven rotation gear. The Moreover, you may connect a rotation gear and each rod with the same length using the transmission wire from which a direction differs more.

  A configuration in which all the gripping claws are provided on the rods connected to the four torque transmission wires coming out of the rotating gear is suitable for the implantation step, and a configuration in which a pair of cutting blades are provided in the lower stage is suitable for the separation step. The sheath tube 5 can be removed at the fitting portion 53 and is convenient for replacement for sterilization treatment or the like. The gap between the gripper driven gear and its drive gear can be removed when autoclaving.

The drive gear is configured such that a tension wire 56 is wound around the outer circumference and the wire is pulled to one side so that the drive gear can be rotated. Both ends of the wire are coupled to an external drive rack 54. Rotate.
Two servo motors for linearly moving the transmission wire are provided for gripping, and one for vertical sliding, and two drive racks 54 are connected to the pinion gear 55 so as to oppose each other. The drive rack 54 converts the rotation of the servo motor into a linear motion via the pinion gear 55 (see FIG. 20). Note that a step motor may be used as the motor.
By connecting the tension wire 56 to the opposing drive rack 54, the pulled wire rotates the driven gear so that there is no effect on the gripping force or gripping balance even if the positional relationship between the motor and the gripping part changes. It becomes possible to operate.

  The pair of rods has a 5 mm vertical slide mechanism, and the position of the gripping claw can be adjusted up and down. As a mechanism for performing this sliding, as shown in FIG. 21, a joint 86 that allows the rod to rotate and restricts sliding in the axial direction is provided on the upper portion of the rod and is fixed to the shaft 84. The rod 84 can be slid up and down by pulling the tension wire 56 so as to give displacement to the spring from the state where the shaft 84 is pressed and positioned in one direction by the spring 80.

  When the servo motor pulls the torque transmission wire in the cable tube, the grip claw 6 is closed, and when it is loosened, the grip claw 6 is opened. By further pulling the torque transmission wire after the gripping claws 6 contact the object, the torque transmission wire is twisted, and as a result, an optimal gripping force is generated in the gripping portion.

  Since the hand unit of the present embodiment uses a torque transmission wire to provide a servo motor outside the hand unit, the hand unit is downsized. The hand part is attached to the manipulator by a bracket 81. The manipulator needs to be capable of translational movement of at least three axes (linear three axes), but it is desirable that the posture of the manipulator can be changed further (six-axis multi-joint).

  With the above configuration, since gripping and sliding control with three degrees of freedom can be configured with a weight of 300 g or less, it is possible to employ a manipulator with a small portable weight (in FIG. In the case of the configuration, it was about 2 kg). That is, when combined with a small manipulator (equivalent to A4 size), it is possible to work on a table and to automate the transplanting process of clone seedlings with a clean bench.

  As shown in FIGS. 23 and 24, the hand unit of this embodiment controls the opening and closing of tweezers with a tension wire. In the configuration of the present embodiment, since it is not necessary to rotate the gripping portion, a combined configuration of an outer tube having both ends fixed and a tension wire penetrating the inside thereof is employed.

The drive rack slides by the drive of the servo motor, and when the tension wire is pulled, the tweezers are closed, and when loosened, the tweezers are opened. The gripping uses the spring characteristics of tweezers, and further pulling the wire after the gripping claws abut against the object causes deflection of the tweezers, resulting in an optimum gripping force at the gripping portion.
Further, in order to attract the tweezers posture in the upright direction with the spring 80, the outer tube 77 is fixed to the opposite side of the spring 80, and the tension wire is pulled to swing the tip of the tweezers around the swing shaft 86. Have This is a mechanism for allowing the gripping claws to reach the seedling of the container even in a configuration in which the posture cannot be controlled (for example, a three-axis translational robot).

  In this embodiment, a speed reduction mechanism using the principle of pulley is provided. When gripping a fragile object such as a plant, it is necessary to finely adjust the stroke of the servo motor. The movement amount is about 1/4 of the stroke of the servo motor, and the driving force is also about 1/4 (actually, it does not become 1/4 because of increased friction). By providing this speed reduction mechanism, it is possible to construct a highly functional hand unit by adopting a low-power compact motor without increasing the wire friction.

In this example, an outer tube having a diameter of 2 mm, a wire diameter of 0.3 mm and a length of 800 mm and a tension wire having a diameter of 0.7 mm were used. In the configuration without the speed reduction mechanism, the correlation between the operating force on the hand side and the pulling force on the motor side was as follows. On the other hand, in the configuration using the pulley of this example, the pulling force of the motor side rack necessary for obtaining a gripping operation force of 200 g was 80 g.
From the results of this example, it was found that the mechanical efficiency could be prevented from decreasing by reducing the force applied to the wire.

As described above, in the case of the combination of the outer tube and the tension wire, the tensile strength necessary for the hand gripping part is several hundred grams, but the force necessary for pulling the tension wire on the rack side is about 3 to 4 times the force. Become. Forcibly pulling with such a large force will reduce the life of the outer tube and tension wire, so the inventor has devised a mechanism to pull the wire with a small force by preparing a small speed reduction mechanism on the hand side. .
In addition, the structure using a pulley is an example, and may be a reduction mechanism using a multistage gear or the like, and the reduction mechanism may be provided on the hand side. At this time, the force applied to the driving wire is preferably 300 g or less.

The hand part of the present embodiment is obtained by providing four cutting mechanisms 85 on the hand part of the sixth embodiment (see FIGS. 25 and 26). A slide blade 86 that can move directly is provided at the tip of the cutting mechanism 85, and the four blades intersect at the center of the tip of the tweezers 81. As shown in FIG. 27, the slide blade 86 is connected to the forward and backward cable tubes, and when the backward wire is pulled by the servo motor, the slide blade 86 moves backward, and when the forward wire is pulled, the slide blade 86 is pulled. Will move forward.
A plant can be separated by grasping a plant stem with tweezers 81 and operating a wire.

This example is an implantation hand constituted by a plurality of tweezers (see FIG. 28). So-called "reverse tweezers" are used, and when no force is applied from the outside, each tweezers is closed with the optimum gripping force, and when the motor driving force is applied, the gripping force gradually decreases. The tweezers will open. In the configuration of this example, by preparing an implantation hand suitable for the plant to be worked in advance, it is possible to obtain an optimum gripping force without performing fine control.
FIG. 29 is a photograph showing a preferred mode of use of the implantation hand of this example. Implanting seedlings that have been adjusted by a machine or hand into a work plate with the same number of holes as the number of tweezers at the same time with the transplanting hand of this embodiment, so that multiple seedlings can be implanted Can be performed simultaneously.
In the present embodiment, the configuration is based on “reverse tweezers”, but the configuration may be such that the optimum gripping force is calculated according to the type of plant. In that case, a configuration using a plurality of normal tweezers is used.
The configuration using the reverse tweezers has an advantage that the upper limit of the gripping force can be easily set. When controlling the gripping force, if it is not necessary to specify an upper limit, normal tweezers may be used.
By holding a plurality of seedlings at the same time, the work efficiency is doubled by increasing the number of treatments per time.
In addition, in the hand which only implants, a person may place a seedling in a supply apparatus, and you may make it perform only an implantation process by a hand.

  According to the present invention, it is possible to automate the process of separating aseptic seedlings cultured in vitro and transferring them to a rooting container in the separation and implantation of sterile clonal seedlings. For example, as shown in FIG. 15, the present invention is applied to the separation station 101 and the planting station 103 in a fully automatic planting station composed of the separation station 101, the adjustment station 102, and the planting station 103. Can do.

It is a perspective view explaining the action | operation of the hand part of this invention. It is drawing of the hand part which has a pair of holding nail | claw and a cutting | disconnection part. It is an enlarged drawing of the front-end | tip part of a hand part which has a pair of holding nail | claw and a cutting | disconnection part. It is drawing explaining the structure of an actuator. It is an enlarged drawing of the fitting part of a sheath pipe. It is drawing of the usage condition of the hand part of this invention. It is a flowchart of operation | movement of the hand part which has a pair of holding nail | claw and a cutting | disconnection part. It is a position change model of a target object and a holding nail. It is a deformation | transformation model in the force transmission path | route in one of the holding claws. It is an experimental result of the grasping force tolerance range in the bud of Eucalyptus. It is drawing of the hand part which has two pairs of a pair of holding claws. It is drawing of the hand part whose holding part is a notch of a sheath pipe. It is an enlarged drawing of the front-end | tip of the hand part whose holding part is a notch of a sheath pipe. It is drawing of the hand part which used the torsion spring in the drive part vicinity. It is a fully automatic implantation station using the present invention. It is a flowchart of the growth process of a clone seedling. It is a perspective view of the hand part using a torque rope. It is a top view of the hand part using a torque rope. It is a side view of the hand part using a torque rope. It is explanatory drawing of the structure for transmitting the drive from a servomotor. It is the A location enlarged view of the hand part using a torque rope. It is B location enlarged view of the hand part using a torque rope. It is a top view of the hand part whose grip part is tweezers. It is a side view of the hand part whose grip part is tweezers. It is the top view of the structure which provided the cutting blade in the hand part whose holding part is tweezers. It is the side view which provided the cutting blade in the hand part whose grip part is tweezers. It is a figure explaining the structure of a cutting blade. It is explanatory drawing of the implantation station which concerns on Example 8. FIG. 10 is a photograph showing an example of using an implantation station according to Example 8.

Explanation of symbols

2 support frame 5 sheath tube 6 gripping part 7 rod 8 fitting part 25 mounting seats 31 to 33 actuator 35 support plate
51 Torque transmission wire shaft through hole 53 Fitting portion 55 Pinion gear 56 Drive rack 57 Servo motor 58 Tension wire 61-63 Grip portion 64 Cutting portion 65 Material having elastic characteristics 66 Cutting blade 67 Gripping shaft 68 Notch 71 Control lever 72 Fixing lever 73 Grasping claw 74 Fragile object 75 Torsion spring 76 Torque transmission wire 77 Outer tube 78 Bracket
79 Block 80 Spring 81 Tweezers 82 Plate 83 Link 84 Shaft 85 Cutting mechanism 91, 95 Carry-in conveyor 92, 96 Rotary table 93, 97 Carry-out conveyor 101 Separation station 102 Adjustment station 103 Implantation station

Claims (9)

A pair of gripping claws, a gripping actuator, and a gripping force transmission system that couples the gripping actuator and the gripping claws;
A part or all of the gripping force transmission system is made of a material having elastic characteristics,
A robot hand that grips a fragile object while causing the gripping force transmission system and / or the gripping claw to bend by driving the gripping actuator. Furthermore, a plurality of cutting blades, a cutting actuator, a cutting force transmission system for connecting the cutting actuator and the cutting blade,
The robot hand according to claim 1, wherein each cutting blade is brought into contact with each other to cut a fragile object by driving the cutting actuator.   The robot hand according to claim 1 or 2, wherein the pair of gripping claws are reverse tweezers set in advance so as to give an optimal gripping force. The gripping actuator is arranged outside the robot hand,
4. The robot hand according to claim 1, wherein the gripping force transmission system is configured to transmit the drive of the gripping actuator to the gripping claws by twisting a torque transmission wire. The gripping actuator is arranged outside the robot hand,
The gripping force transmission system consists of a tension wire that passes through the outer tube,
4. The robot hand according to claim 1, wherein the pair of gripping claws are tweezers that are opened and closed by the tension wire.   The robot hand according to any one of claims 1 to 5, further comprising a speed reduction mechanism in which a stroke or a rotation angle transmitted from the gripping actuator to a gripping claw and a driving force is 1 / n.   The robot hand according to any one of claims 1 to 6, wherein the gripping claw is movable up and down by a certain width.   The robot hand according to claim 1, wherein the gripping claw is detachable. The robot hand according to claim 1, comprising a plurality of the pair of gripping claws.