JP2010110846A - Robot hand and control device used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a robot hand holding target objects having a wide variety of shapes, with a simple structure and by easy control, and also to provide a control device used for the robot. <P>SOLUTION: A plurality of fingers including a bendable finger part, a rigidity imparting part reversively controllable between a low rigidity state and a high rigidity state, and an expandable abutting part contactable with the object are arranged at a base part. When the rigidity imparting part is in the low rigidity state, the abutting part is made to contact with the object by bending the finger part. The rigidity imparting part is hardened into the high rigidity state, the abutting part is expanded, and holding force is generated between the object and the rigidity imparting part, so that the object is held. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a robot hand and a robot hand control device capable of gripping objects of various shapes, for example, for performing work on behalf of a person in a factory or home.

  Conventionally, a robot hand used for a factory is composed of a pair of flat plates kept parallel by parallel links, and grips a rectangular parallelepiped shaped member as a gripping object with a pair of flat plates, The robot hand that grips a gripping object having a specific shape is mainly used.

  However, such a robot hand is not versatile, and when the object to be grasped is changed, the robot hand cannot accurately grasp the object to be grasped, so a separate robot corresponding to the new object to be grasped. There was a problem that a hand was needed.

  Therefore, there is a demand for realization of a robot hand that can grasp a wide variety of shapes of gripping objects, and there are the following techniques for realizing this.

  For example, as a conventional technique (first conventional example), there is a technique that realizes high versatility like a human hand by configuring a robot hand to have a multi-degree-of-freedom configuration equivalent to or higher than a human finger ( Patent Document 1).

  The technique of the first conventional example will be described with reference to FIG. FIG. 26 illustrates a first conventional robot hand.

  By connecting the rotary links 51 in series and facing each other, a structure of two opposing fingers is formed, and at the tip of the structure of the two fingers, a wire 52 for transmitting a force for closing the two fingers and Wires 54 for transmitting the force to open two fingers are connected to each other. Since each wire 54 always outputs a force in an opening direction by a spring 55 connected to the base portion 56, the finger driving portion 53 transmits the driving force via the two wires 52 in the two finger structure. The gripping operation of the gripping target object 50 by two fingers is canceled by the force of the two springs 55 when the driving force is not output. Is done.

  Further, as another conventional technique (second conventional example), a portion that comes into contact with the gripping object 65 is deformed according to the outer shape of the gripping object 65 when pressed against the gripping object 65. There is a technique of a second conventional example that realizes versatility (see Patent Document 2).

  An example of the technique of the second conventional example will be described with reference to FIG. FIG. 27 illustrates a robot hand according to a second conventional example, in which a pair of gripping portions 62 are coupled to a base member 64 connected to a manipulator (not shown) via four parallel links 63. The pair of gripping parts 62 are driven so as to be closed (approached to each other) by an actuator (not shown) while keeping parallel. An elastic film or an elastic body is used for the abutting portion 61 of each gripping portion 62 that comes into contact with the gripping target object 65, and is pressed against the gripping target object 65 by the gripping portion 62. The contact portion 61 is deformed according to the shape.

Japanese Patent Publication No. 4-6509 JP 59-24981 A

  However, in the first conventional example, in order to realize multiple degrees of freedom, the number of mechanical parts such as the link 51 is increased, resulting in a complicated structure and a uniform gripping force according to the gripping object. In this case, since many degrees of freedom must be controlled appropriately, the control becomes very complicated.

  In the second conventional example, if the elasticity of the contact portion 61 is high, the deformation amount of the contact portion 61 is small and the versatility is low. If the elasticity of the contact portion 61 is low, an external force is applied to the contact portion 61. Since the abutting portion 61 is greatly deformed even when the pressure is applied, the grasping operation of the grasped object becomes unstable. Therefore, high versatility cannot be realized only by the conventional technique shown in the second conventional example. Although it is necessary to combine with an example, in that case, similarly to the first conventional example, the structure becomes complicated and the control becomes complicated.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems, and to provide a robot hand and a robot hand control device capable of gripping a wide variety of gripping objects with a simple structure and simple control. It is to provide.

  In order to achieve the above object, the present invention is configured as follows.

According to a first aspect of the present invention, a base portion;
A plurality of finger portions disposed on the base portion so as to face each other and bendable;
By disposing at least one of the plurality of finger portions on the surface on the gripping side of the object to be gripped, and bending from the low rigidity state that can be bent according to the one finger portion, Rigidity imparting part capable of reversibly transitioning between a high rigidity state in which the rigidity is higher than the low rigidity state and the bent shape can be maintained in a bent state;
A contact portion that is disposed on a surface of the gripping object on the gripping side of the gripping object, is in contact with the gripping object, is inflatable, and can be contracted so as to be separated from the gripping object. A robot hand characterized by the above is provided.

  According to a second aspect of the present invention, there is provided the robot hand according to the first aspect, wherein the rigidity imparting portion is disposed so as to cover all the movable points of the finger portion.

  According to a third aspect of the present invention, there is provided the robot hand according to the first or second aspect, wherein the contact portion is disposed so as to cover all the movable points of the finger portion.

  According to a fourth aspect of the present invention, there is provided the robot hand according to any one of the first to third aspects, wherein each of the plurality of finger portions includes the rigidity imparting portion and the contact portion. .

  According to the fifth aspect of the present invention, the rigidity imparting portion is a material capable of reversibly controlling the hardness between the low rigidity state and the high rigidity state while maintaining the shape, A robot hand according to any one of the first to fourth aspects, wherein a functional fluid is used.

According to the sixth aspect of the present invention, the rigidity imparting unit reversibly controls the hardness between the low rigidity state and the high rigidity state using ER fluid or ER gel while maintaining the shape. A hardened part that can be
The hardened portion has a pair of electrodes facing each other in the insulating thin film, an insulating spacer is disposed between the pair of electrodes in the thin film, and the ER is placed in a space between the electrodes in the thin film. The robot hand according to any one of the first to fourth aspects is configured by a sheet-like structure enclosing a fluid or an ER gel, and the sheet-like structure is formed by stacking a plurality of layers. provide.

  According to the seventh aspect of the present invention, the rigidity imparting unit reversibly and arbitrarily controls the hardness between the low-rigidity state and the high-rigidity state using MR fluid while maintaining the shape. The hardened portion can be disposed between the magnetic members by disposing a pair of magnetic members facing each other and connecting each end of the magnetic members via an electromagnet. The robot hand according to any one of the first to fourth aspects is provided, which is configured to generate a magnetic field in the enclosed MR fluid.

  According to the eighth aspect of the present invention, the rigidity imparting section uses a clay having dry curability that is a Bingham fluid, and the hardness is maintained between the low rigidity state and the high rigidity state while maintaining the shape. The sheet-like module in which the clay is disposed between the moisture-impermeable film and the moisture-permeable film disposed opposite to each other, The moisture permeable films are arranged so that the moisture permeable films face each other and are arranged in a hollow sheet shape, and water vapor or dry air is passed through the sheet hollow space between the opposed moisture permeable films. A robot hand according to any one of the first to fourth aspects is provided, wherein the robot hand is controlled so as to be in the low rigidity state or the high rigidity state.

According to a ninth aspect of the present invention, in the robot hand control device for controlling the operation of the robot hand according to any one of the first to eighth aspects,
In the gripping operation, first, the rigidity imparting portion is controlled to be softened to the low rigidity state,
After that, the contact portion is passively deformed together with the finger portion and the hardened portion by pressing the contact portion against the outer surface of the grasped object by the bending operation of the finger portion,
It is controlled so that the rigidity applying portion is cured to the high rigidity state while maintaining the deformed state after the deformation,
There is provided a control device for a robot hand in which a gripping force is generated between the gripping object and the curing part by the contact part expanding after curing, and the robot hand grips the gripping object.

  According to the robot hand and the robot hand control device as described above, the number of parts is reduced by eliminating the need for the rotation connecting portion, and the control of the hand shape is realized not by the position control of the actuator but by the hardness control of the hardened portion. Therefore, it is possible to realize a robot hand capable of gripping objects of various shapes with a simple structure and simple control.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, after explaining the outline of the structure of the robot hand according to the first embodiment of the present invention in FIGS. 1A and 1B, the outline of the gripping operation according to the robot hand of the first embodiment is explained in FIGS. 2A to 2E. 3A to 7A and 7B, a detailed description will be given of the curing portion, the contact portion, and the finger portion of the robot hand.

  The structure of the robot hand according to the first embodiment will be described with reference to FIGS. 1A to 1C.

  1A is a schematic side view of the robot hand according to the first embodiment, FIG. 1B is a schematic front view of the robot hand, and FIG. 1C is an outline of the robot hand when gripping a gripping object having a shape different from that of FIG. 1A. It is a side view.

  As shown in FIGS. 1A to 1C, the robot hand according to the first embodiment includes three curing portions 1, three contact portions 2, and three finger portions 3 as an example of a rigidity imparting portion. The robot hand base unit 4 is connected to the manipulator 6 via the base unit 4, and the three finger units 3 of the robot hand are positioned with respect to the grasped object 5 by the manipulator 6. The object to be grasped 5 is grasped by the hand. The three fingers 3 are, for example, arranged on the upper side with the finger 100a composed of the two fingers 3, the contact part 2, and the hardened part 1, and on the upper side between the two fingers 3 below. In addition, one finger part 3 on the lower side is arranged.

  Each curing portion 1 is arranged in an elongated plate shape so as to continuously cover the inner surface of each finger portion 3 (the surface facing the object to be grasped 5), and one end of each curing portion 1 is fixed to the base portion 4. The other end of each cured portion 1 is opened at the tip side of each finger portion 3, and the relative positional relationship between the finger portion 3 where the cured portion 1 is disposed and the cured portion 1 is changed. It is arranged to be able to. Each hardening part 1 is comprised with the material which can control hardness reversibly, and each hardening part 1 can change hardness, keeping the shape. In other words, the hardened portion 1 has a low rigidity state that can be bent in accordance with the finger portion 3 and a high rigidity that can be bent and maintained in a bent state by being hardened from the low rigidity state and having a higher rigidity than the low rigidity state. It is configured to be able to reversibly move between states. Examples of such a material for each hardening section 1 include a functional fluid such as an ER (Electrorheological) fluid, an ER gel, or an MR (Magnetorheological) fluid, or a clay having a dry hardening property among Bingham fluids. There are materials. Details of these materials will be described later. By disposing each curing part 1 as described above, each curing part 1 is cured, whereby the gripping force and the external force can be supported by the rigidity of each curing part 1.

  Moreover, each hardening part 1 is comprised so that thickness may reduce, so that it leaves | separates from the base part 4. FIG. In each hardening part 1, the thickness between the root part and the tip part of each hardening part 1 fixed to the base part 4 is based on the thickness of the root part and the tip part, and depends on the distance from the base part 4. As long as the thickness obtained by decreasing in a quadratic function is at least secured, the thickness from the root portion to the tip portion may be changed in any way, but from the viewpoint of weight, the base portion 4 A structure in which the thickness decreases in a quadratic function according to the distance from is used. In this way, by making the thickness of the base portion of each cured portion 1 thicker than the tip portion, it becomes possible to stably support the moment due to the gripping force by each cured portion 1.

  Each contact portion 2 is configured by a hollow member that can inject a pressure fluid, and is disposed on the inner surface of each curing portion 1 (surface that can come into contact with the object to be grasped 5). After curing according to the outer shape of the object 5, the abutting part 2 is expanded between the gripping object 5 and the curing part 1 by injecting a pressure fluid into the abutting part 2. The gripping force of the entire robot hand is generated by the internal pressure.

  Each finger part 3 is composed of a hollow member in which the inner material and the outer material are different in terms of expansion / contraction rate and can inject air, and the root part of each finger part 3 is attached to the base part 4, respectively. By injecting air into the finger part 3, a bending operation is realized due to the difference between the expansion ratio of the inner material of the finger part and the expansion ratio of the outer material. Each finger 3 is arranged on the outermost surfaces of the hardened part 1 and the contact part 2 so that the hardened part 1 and the contact part 2 can be driven simultaneously.

  FIGS. 1A and 1B show a state in which a cylindrical member as an example of the grasped object 5 is grasped by the robot hand according to such a configuration. In these drawings, each contact portion 2 and each hardened portion 1 are deformed and hardened into an arc shape so as to follow the outer peripheral arc of the cylindrical member. FIG. 1C shows a state in which the robot hand grips a pillar member having a polygonal cross section as another example of the gripping object 5. In this figure, each contact part 2 and each hardening part 1 are deformed and hardened into a shape bent along the outer surface of the polygonal column member.

  The outline of the gripping operation of the robot hand in the first embodiment will be described below with reference to FIGS. 2A to 2E.

  2A to 2E illustrate a series of flows of the gripping operation of the robot hand in the first embodiment.

  First, as shown in FIG. 2A to FIG. 2B, with the three fingers 3 opened, the manipulator 6 brings the center (for example, the base 4) of the robot hand 100 closer to the cylindrical gripping object 5. .

  Subsequently, after the center part (for example, the base part 4) of the robot hand 100 approaches the gripping target object 5 (that is, after the completion of the approaching operation is detected), as shown in FIG. 2B to FIG. 3 (refer to the hatched portion in FIG. 2C), the hardened portion 1 and the contact portion 2 of each finger portion 3 are brought closer to the outer periphery of the grasped object 5.

  Subsequently, after each finger part 3 is placed along the outer periphery of the grasped object 5 (that is, after the completion of the follow-up operation), as shown in FIGS. 2C to 2D, the hardening part 1 (see FIG. 2D) of each finger part 3. 2D hatched portion) is cured, and each cured portion 1 is allowed to follow the outer periphery of the object 5 to be grasped. A specific curing method will be described later.

  Finally, as shown in FIG. 2D to FIG. 2E, each contact portion 2 is expanded after the cured portion 1 of each finger portion 3 is cured, so that each contact between the gripping object 5 and each cured portion 1 is performed. A gripping force is generated by the internal pressure of the contact portion 2. After the expansion of each contact portion 2 is completed (that is, after completion of gripping force generation is detected), the gripping operation of the robot hand 100 with respect to the gripping object 5 is completed.

  Conversely, when releasing the gripping operation of the robot hand 100 with respect to the gripping object 5, for example, the above operation may be reversed.

  That is, first, as shown in FIGS. 2E to 2D, gripping generated by the internal pressure of each contact portion 2 between the gripping object 5 and each curing portion 1 by contracting each contact portion 2. The force is released, and the holding operation of the robot hand 100 with respect to the holding object 5 is released.

  Next, as shown in FIG. 2D to FIG. 2C, the cured portion 1 of each finger portion 3 (see the hatched portion in FIG. 2D) is softened, and each cured portion 1 is separated from the outer periphery of the grasped object 5. A specific softening method will be described later.

  Next, as shown in FIG. 2C to FIG. 2B, by driving the three finger portions 3 (see the hatched portion in FIG. 2C) in the opposite direction to the gripping operation, the hardened portions 1 of each finger portion 3 and The contact portion 2 is separated from the outer periphery of the grasped object 5.

  Next, as shown in FIG. 2B to FIG. 2A, the center part (for example, the base part 4) of the robot hand 100 is separated from the grasped object 5 by the manipulator 6 with the three finger parts 3 opened.

  Next, in order to execute the gripping operation and the grip releasing operation (opening operation) described above, FIGS. 3A to 3C, FIGS. 6A and 6B, FIG. This will be described in detail with reference to FIG. 7B.

  As a material constituting the hardened portion 1 whose hardness is reversibly and arbitrarily controllable, ER fluid, ER gel, or MR fluid that is a functional fluid exhibiting Bingham fluid behavior, or clay that is a kind of Bingham fluid Etc. can be used.

  ER fluid or ER gel is a material whose hardness changes according to the strength of an applied electric field, and MR fluid is a material whose hardness changes according to the strength of an applied magnetic field. Clay is a material that has dry curability and changes in hardness depending on moisture content.

  The hardening part 1 using ER fluid or ER gel is characterized in that it can be used universally because it does not give the influence of magnetic force to the object to be grasped and does not require special infrastructure such as dry air. On the other hand, since MR fluid or clay generally has a higher yield point than ER fluid or ER gel, depending on the gripping object or the usage environment of the robot hand, the hardened portion 1 using the ER fluid or ER gel Has advantages in terms of size and weight. For example, in the case of a target that is not affected by a magnetic force such as gripping a non-magnetic material, a module using MR fluid is preferable, but in a factory or the like, a dry air or water vapor infrastructure (in other words, supply of dry air or water vapor) In an environment where facilities are in place, modules using clay are preferred.

  Hereinafter, the curing unit 1 will be described more specifically.

  First, FIGS. 3A, 3B, and 3C are a schematic perspective view, a plan view, and a cross-sectional view taken along the line III-III in FIG. 3B of the curing unit 1 using an ER fluid.

  The curing unit 1 has a structure in which a plurality of sheet-like modules 1A are laminated to improve rigidity, and the laminated structure is covered with an outer peripheral film 12. The sheet-like module 1A includes an insulating thin film body 11. The positive electrode 9 and the negative electrode 10 sandwich the insulating sheet 8 in which holes are formed so as to form through holes 8a at a predetermined interval as shown in FIGS. 3B and 3C, and The ER fluid 7 is sealed in the remaining internal space by avoiding the through holes 8a of the insulating sheet 8 functioning as insulating spacers. In addition, the positive electrode 9 and the negative electrode 10 are respectively bonded and fixed to the thin film body 11 in order to suppress the change in the internal electric field strength due to the change in the thickness of the sheet-like module 1A. And the voltage is applied to the positive electrode 9 and the negative electrode 10 from the power supply 14 arrange | positioned through the power supply line 13, and the sheet-like module 1A hardens | cures when the ER fluid 7 hardens | cures. On the contrary, when the voltage application from the power source 14 to the positive electrode 9 and the negative electrode 10 is removed, the ER fluid 7 is softened to soften the sheet-like module 1A.

  Next, FIG. 6A and FIG. 6B are a schematic plan view of the hardening part 1 using MR fluid and a sectional view taken along line VI-VI in FIG. 6A as a modification of the first embodiment.

  The sheet-like module 1B of the curing unit 1 includes a pair of magnetic sheets 31 as an example of a magnetic member having high magnetic permeability in which a magnetic powder such as iron is mixed, and a pair of magnetic sheets 31. It has a bag-like structure formed by a non-magnetic material sheet 32 such as a rubber sheet that connects the side end portions, and the pair of magnetic material sheets 31 are arranged to face each other. Here, the magnetic member having a high magnetic permeability is a permeability of 10 times or more of the material constituting the member (base portion 4, finger portion 3, contact portion 2) other than the hardened portion 1 that contacts the magnetic sheet 31. It means a magnetic member having magnetic susceptibility.

  Inside the sheet-like module 1B, a non-magnetic material sheet 33 in which a through-hole 33a is drilled with a non-magnetic material to prevent contact between the magnetic material sheets 31 is arranged, and inside the sheet-like module 1B, , MR fluid 34 is enclosed.

  The magnetic sheet 31 is connected via a magnetic body 35 and an electromagnet 36, and the electromagnet 36 is operated by an electromagnet drive power source 37 (in other words, when energized or energized current is increased), A magnetic field is generated or increased between the opposing magnetic sheets 31, a magnetic field is generated or increased in the MR fluid 34, and the MR fluid 34 is cured, whereby the sheet-like module 1B is cured. Conversely, when the electromagnet 36 is not operated by the electromagnet drive power source 37 (in other words, when the electromagnet 36 is deenergized or the energization current is reduced), the magnetic field between the opposing magnetic sheets 31 disappears or becomes small, The magnetic field disappears or becomes small in the MR fluid 34, and the MR fluid 34 is softened, whereby the sheet-like module 1B is softened.

  Next, FIG. 7A and FIG. 7B are a schematic plan view of the hardening part 1 using clay and a sectional view taken along line VII-VII in FIG. 7A as another modification of the first embodiment.

  In the sheet-like module 1C of the curing unit 1, for example, clay 42 is disposed between a moisture-impermeable film 41 and a moisture-permeable film 43 used for building materials, and an air flow path is provided at the center of the sheet-like module 1C. A space 44 exists, and an air flow path 45 is connected to one end of the space 44 and an exhaust port 49 is connected to the other end.

  A dry air valve 46A, a dry air pump 47 for injecting dry air, a water vapor valve 46B, and a water vapor pump 48 for injecting water vapor are connected to the sheet-like module 1C through an air flow path 45. The dry air valve 46A and the water vapor valve 46B are appropriately controlled to open and close, and by flowing dry air or water vapor or both, the moisture content of the clay 42 is changed via the moisture permeable film 43, The hardness of the clay 42 is controlled. For example, supplying dry air from the dry air pump 47 reduces the moisture content of the clay 42 through the moisture permeable film 43 to harden the clay 42, while supplying water vapor from the water vapor pump 48 allows the water to pass through. The clay 42 can be softened by increasing the moisture content of the clay 42 through the wet film 43.

  For example, when a 100 g plastic bottle-like object is gripped by three fingers 3 as an example of the gripping object 5, as a specific example of the curing unit 1 using the ER fluid 7 attached to each finger 3, The overall thickness of the laminated structure is about 30 mm wide and about 100 mm long. The thickness of the root portion of the hardened portion 1 is 30 mm, and the thickness of the tip portion of the hardened portion 1 is about 10 mm between the root portion and the tip portion. Is a structure that decreases in a quadratic function according to the distance from the root. As a single sheet-like module 1A, an electric field of 2 kv / mm is obtained by applying a voltage of 1 kv from the power source 14 to the sheet-like module 1A having a thickness of 0.5 mm using the insulating sheet 8 having a thickness of 0.1 mm. Any structure may be used as long as it generates the above. As the ER fluid 7 used inside, an ER fluid that yields a yield stress of 20 kpa or more when an electric field of 2 kv / mm is applied is used.

  On the other hand, the contact portion 2 that generates a gripping force between the curing portion 1 and the gripping object 5 will be described in detail with reference to FIGS. 4A and 4B.

  A bag-like structure using a pressure fluid can be used as a mechanism for generating a gripping force between the cured part 1 and the gripping target object 5 in the contact part 2. By using air as an example of the pressure fluid, a lightweight robot hand 100 can be realized. On the other hand, when a strong gripping force is required for the robot hand, it is preferable to use a liquid having a low compressibility and easy to use at high pressure as the pressure fluid. An example of such a liquid is water.

  4A and 4B are a perspective view and a schematic configuration diagram of the contact portion 2 using air as a pressure fluid.

  Each abutting portion 2 is composed of, for example, a plurality of hollow circular inflating portions 15 made of a material having high ductility such as rubber, and a non-inflating portion 16 made of a material having low ductility such as vinyl. A space 17 serving as an air flow path connected to each expansion portion 15 is secured inside the expansion portion 16. By injecting air into the space 17 from the air pump 20 disposed outside the contact portion 2 via the valve 19 and the air flow path 18, each expansion portion 15 expands and is gripped by internal pressure. Can generate power. Conversely, when the air pump 20 is stopped and the air in the space 17 is discharged from the valve 19 to contract each expansion portion 15, the internal pressure is reduced and the gripping force can be released.

  As an example of the object to be grasped 5, when a 100 g plastic bottle-like object is grasped by the three finger portions 3, each contact portion 2 has the same size as the surface of the above-described curing portion 1 and has a width of 30 mm as a whole. The sheet has a length of about 100 mm, and by injecting air at atmospheric pressure into the contact portion 2, it is possible to generate a gripping force sufficient for gripping a plastic bottle-like object.

  Furthermore, each finger | toe part 3 which drives the hardening part 1 and the contact part 2 is demonstrated in detail using FIG.

  In each finger part 3, a conventional hand having multiple degrees of freedom can be used. In particular, the air-driven robot hand 100 can reduce the weight of the robot hand 100.

  FIG. 5 is a schematic view of the finger portion 3 that bends the finger by air driving.

  The finger part 3 is made of a material having a large elasticity such as rubber and disposed on the outside, and is made of a material having a low elasticity compared to the expansion part 22 such as vinyl, and is located on the inside of the expansion part 22. It has the cylindrical structure comprised by the non-expandable part 21 arrange | positioned in.

  By injecting air from the air pump 25 through the valve 24 and the air flow path 23 into the space 26 in the cylindrical structure, the inner non-stretchable portion 21 and the outer stretchable portion 22 can be easily extended. Due to the difference, the cylindrical structure is driven to bend. On the contrary, when the air pump 25 is stopped and the air in the space 26 is discharged from the valve 24, the cylindrical structure has such rigidity that the non-stretchable part 21 and the stretchable part 22 return to the original non-bent state. It is composed.

  As an example of the object 5 to be grasped, when an object on a 100 g plastic bottle is grasped by three finger parts 3, the finger part 3 has a size that allows the above-described curing part 1 and abutment part 2 to be attached. As a whole, the width may be about 30 mm, the length is 110 mm, and the thickness is about 20 mm. As the air to be injected, air at atmospheric pressure is used as in the contact portion 2.

  FIG. 12 is a control block diagram of a control unit and the like for realizing the operation of the robot hand 100.

  The control unit (control device) 108 includes a general control unit 106 that comprehensively controls the overall operation of the robot hand 100, a manipulator control unit 107, a hand control unit 109, a curing unit control unit 121, and a contact unit control unit 122. And a finger control unit 123.

  The general control unit 106 is connected to a manipulator control unit 107 and a hand control unit 109. The manipulator control unit 107 controls driving of the manipulator driving unit 101 that drives the manipulator 6. The hand control unit 109 controls a gripping operation of the robot hand 100 and is connected to the curing unit control unit 121, the contact unit control unit 122, and the finger unit control unit 123.

  The curing unit control unit 121 drives and controls the curing unit driving unit 111 that drives each curing unit 1. Specifically, the curing unit control unit 121 controls, as the curing unit drive unit 111, the power supply 14 and the opening / closing of the switch 14a for switching on / off of the power supply 14, or only the opening / closing of the switch 14a. . The contact part control unit 122 drives and controls the contact part drive unit 112 that drives each contact part 2. Specifically, the contact part control unit 122 controls the drive of the air pump 20 and the opening and closing of the valve 19 as the contact part drive unit 112. The finger control unit 123 drives and controls the finger driving unit 113 that drives each finger 3. Specifically, the finger control unit 123 controls the driving of the air pump 25 and the opening and closing of the valve 24 as the finger driving unit 113.

  The overall control unit 106 controls the operations of the approach detection unit 102, the contact detection unit 103, the follow-up operation detection unit 104, the gripping force detection unit 105, and the curing completion detection unit 110. Detection information from the detection unit is input to the general control unit 106.

  The contact detection unit 103 is a contact sensor as an example, and corresponds to a case where a contact sensor is used as the approach detection unit 102 or a contact sensor is used as the follow-up operation detection unit 104. It also functions as the operation detection unit 104 or the similar operation detection unit 104.

  As shown in FIG. 2B, the approach detection unit 102 moves the robot hand 100 toward the gripping object 5 when the robot hand 100 approaches the gripping object 5 (for example, a contact operation or within a predetermined distance). This is used to detect whether or not the “approaching action” has been completed, and is used when executing the “approaching action completion detection” step described later. The approach detection unit 102 will be described with reference to FIGS. 13A to 13H.

  As an example of the approach detection unit 102, as shown in FIGS. 13A and 13B, a contact sensor 71 is arranged on the hand base unit 4 or the contact unit 2, and the base unit 4 or contact is detected by a contact detection signal from the contact sensor 71. The contact of the grasped object 5 with the part 2 can be detected, and the completion of the approaching operation in FIG. 2B can be detected. More specifically, FIGS. 13A and 13B show a state in which the contact sensor 71 is disposed in the center portion of the hand base portion 4 and in the vicinity of the tip portion of each contact portion 2. This contact sensor 71 can also be used as a follow-up action detection unit 104 for performing a “follow-up action completion detection” step, which will be described later. As a whole, the number of sensors can be reduced.

  As another example of the approach detection unit 102, as shown in FIGS. 13C and 13D, a known image such as a background difference method or the like using an image sensor 72 provided in the hand base unit 4 and an image acquired by the image sensor 72 is used. The image processing unit 72A is configured to perform processing, and the image acquired by the image sensor 72 is image-processed by the image processing unit 72A to detect completion of the approaching operation of the robot hand 100 to the grasped object 5. it can. Further, by providing the image sensor 72 outside the robot hand 100, the completion of the approaching operation can be detected (see FIGS. 13E and 13F). With such a configuration, in particular, when the image sensor 72 is used for motion control of the manipulator 6, it is possible to detect the completion of the approaching operation from the sensor information, so it is necessary to mount the sensor on the robot hand 100. Therefore, the weight of the robot hand 100 can be reduced by reducing the number of sensors.

  As still another example of the approach detection unit 102, a distance measuring sensor 73 is mounted on the robot hand 100, and the approach operation is performed based on the distance data between the robot hand 100 and the grasped object 5 detected by the distance measuring sensor 73. Completion detection can also be performed (see FIGS. 13G and 13H). It is difficult to bring the robot hand 100 into contact with the object 5 to be grasped, such as poor positioning accuracy of the manipulator 6 by detecting the completion of the approaching operation based on the distance data detected by the distance measuring sensor 73 without depending on the contact. Even in this case, the completion of the approaching operation can be detected efficiently.

  Further, as shown in FIG. 2C, the follow-up motion detection unit 104 detects whether or not the so-called follow-up operation in which each finger unit 3 is moved along the outer periphery of the grasped object 5 is completed. This is used when executing the “detection of completion of tracing operation” step. The following motion detection unit 104 will be described with reference to FIGS. 14A to 14F.

  As an example of the profile detection unit 104, a method of installing a plurality of contact sensors 75 at intervals in the longitudinal direction of each contact unit 2 and detecting the completion of the profile operation by detecting the contact of all the contact sensors 75. (See FIGS. 14A and 14B). According to such a configuration, it is possible to reliably detect the completion of the follow-up operation, and also to use the data acquired by the sensor by causing the same sensor to function as the approach detection unit 102 in the approach operation completion detection step. The weight of the robot hand can be reduced by reducing the number of sensors.

  As another example of the follow-up motion detection unit 104, an image sensor 77 provided outside the robot hand 100, and an image processing unit 77A that processes an image acquired by the image sensor 77 by known image processing such as a background difference method. The image processing unit 77 performs image processing on the image acquired by the image sensor 77, detects that each finger unit 3 is placed along the outer periphery of the grasped object 5, and detects the completion of the follow-up operation. You can also According to such a configuration, the weight of the robot hand 100 can be reduced by reducing the number of sensors as in the approaching operation completion detection step (see FIGS. 14C and 14D).

  Further, as another example of the follow-up motion detection unit 104, by disposing a plurality of distance measuring sensors 78 at intervals in the longitudinal direction of each contact portion 2, the distance data detected by the distance measuring sensor 78 is 0. Is detected as a contact between the gripping object 5 and the robot hand 100. Therefore, when the distance data from each distance measuring sensor 78 becomes 0, it is possible to function as the operation detector 104 that detects the completion of the operation (see FIGS. 14E and 14F).

  In addition, as shown in FIG. 2E, the gripping force detection unit 105 has completed the gripping force generation operation for generating the gripping force between the gripping object 5 and the curing unit 1 by the internal pressure of the contact portion 2. This is used when executing a “detection of completion of gripping force” step described later. The gripping force detection unit 105 will be described with reference to FIGS. 15A to 15D.

  As an example of the gripping force detection unit 105, a pressure sensor or a force sensor 74 is installed on the surface of each contact portion 2, and a target value set according to the force detected by the pressure sensor or the force sensor 74 and the gripping object 5. By comparison with (by comparison with the control unit), detection of the completion of gripping force generation can be realized. According to such a configuration, by directly measuring the force generated on the surface of each contact portion 2, the pressure sensor or the force sensor 74 is also used for control such as fine adjustment of the gripping force. Data can be used (see FIGS. 15A and 15B).

  Further, as another example of the gripping force detection unit 105, the gripping force detection unit 105 is connected to the air flow path 18 connected to the air pump 25 that is a driving source of each contact part 2 via the valve 76 a and supplied through the air flow path 18. The pressure of the pressure fluid is measured by the pressure gauge 76, and the detection of the completion of the gripping force is detected by comparing the value detected by the pressure gauge 76 with a preset threshold value (by comparison in the control unit). Can be realized. Since the force measurement is not performed directly, the measurement accuracy is reduced, but the pressure gauge 76 as an example of the pressure measuring device can be disposed in the vicinity of the driving source, so that it is not necessary to add a sensor to the robot hand 100. The weight of the robot hand 100 can be reduced (see FIGS. 15C and 15D).

  Further, the curing completion detection unit 110 measures in advance the time required for curing of the curing unit 1 after the curing of the curing unit 1 is started, and the elapsed time after the curing unit 1 starts curing reaches the measurement time. By this, it can be configured by means that is regarded as completion of curing. Although the curing completion detection unit 110 can be configured with a displacement measuring device such as measuring the displacement of each curing unit 1 by applying a force to each curing unit 1, compared with such a displacement measuring device, This can be realized without adding a sensor or the like, and the weight of the robot hand 100 can be reduced.

  As a whole configuration of the robot hand 100, a structure as shown in FIG. 8 can be adopted. As shown in FIG. 8, each finger unit 3 is configured to have a drive source independently, whereby each finger unit 3 can be controlled independently, and the fingertips of specific finger units 3 (for example, Operations other than the gripping operation such as manipulating an object with one or two fingertips) can also be realized.

  Further, as a modification of the first embodiment, as shown in FIG. 9, the driving source of each finger unit 3 is configured by one common driving source, thereby simplifying the overall structure and reducing the number of parts. Can be planned.

  Hereinafter, the gripping operation and the grip releasing operation of the robot hand 100 will be described in detail.

  The gripping operation of the robot hand 100 is realized as shown in FIGS. 2A to 2E and FIG. 10A under the control of the control unit 108.

  First, in step S1, each hardening part 1 is made into a soft state (refer FIG. 2A). In other words, as described with reference to FIGS. 3A and 3B, FIGS. 6A and 6B, FIGS. 7A and 7B, the sheet-like modules 1A of the curing units 1 are softened. For example, when the ER fluid 7 is used for each curing unit 1, voltage application from the power source 14 to the positive electrode 9 and the negative electrode 10 in FIG. 3B is removed by the control of the curing unit control unit 121 (for example, The switch 14a is turned off), and the ER fluid 7 is softened to soften the respective sheet-like modules 1A of the respective hardened portions 1.

  Next, in step S2, each contact portion 2 is contracted (see FIG. 2A). That is, the air pump 20 of FIG. 4B is stopped by the control of the contact part control unit 122, the air in the space 17 of each contact part 2 is discharged from the valve 19, and each expansion part of each contact part 2 is discharged. 15 is shrunk and the internal pressure of each contact part 2 is reduced.

  Next, in step S3, all the finger parts 3 are opened (see FIG. 2B). That is, under the control of the finger control unit 123, the air pump 25 of FIG. 5 is stopped, the air in the space 26 is discharged from the valve 24, and each finger 3 is returned to the non-bent state.

  Next, in step S4, the robot hand 100 is moved closer to the grasped object 5 (see FIG. 2B). That is, the central part (for example, base part 4) of the robot hand 100 in which all the finger parts 3 are opened via the manipulator 6 by driving the manipulator driving part 101 with the three finger parts 3 opened. Is brought closer to the grasped object 5.

  Next, in step S5, the approach detection unit 102 determines whether or not the approach operation of the robot hand 100 to the grasped object 5 is completed (see FIG. 2B). That is, as shown in FIGS. 13A to 13H, in the approach detection unit 102, a contact operation of the robot hand 100 with respect to the grasped object 5 or an operation in which the robot hand 100 approaches the grasped object 5 within a predetermined distance. Detect whether or not is completed. When the control unit 108 determines that the approaching operation with respect to the grasped object 5 of the robot hand 100 is not completed based on the detection information from the approach detecting unit 102, the step S5 is repeated. On the other hand, when the control unit 108 determines that the approaching operation of the robot hand 100 with respect to the grasped object 5 is completed based on the detection information from the approach detecting unit 102, the process proceeds to the next step S6.

  In step S6, each finger part 3 is closed (refer FIG. 2C). That is, under the control of the finger control unit 123, the air pump 25 of FIG. 5 is driven to supply air into the space 26 via the valve 24, and each finger 3 is bent to hold the object 5 to be grasped. Is surrounded by all fingers 3.

  Next, in step S7, the follow-up operation detector 104 determines whether or not the follow-up operation is completed (see FIG. 2C). That is, as shown in FIGS. 14A to 14F, the follower motion detection unit 104 detects whether or not the so-called follower operation that moves each finger 3 along the outer periphery of the grasped object 5 is completed. When the control unit 108 determines that the follow-up operation is not completed based on the detection information from the follow-up operation detection unit 104, the process returns to step S6. On the other hand, if the control unit 108 determines that the follow-up operation is completed based on the detection information from the follow-up operation detection unit 104, the process proceeds to the next step S8.

  In step S8, as shown in FIG. 3A and FIG. 3B, FIG. 6A and FIG. 6B, or FIG. 7A and FIG. 7B, each hardening part 1 is made into a hard state (refer FIG. 2D). That is, for example, when the ER fluid 7 is used for each curing unit 1, a voltage from the power source 14 is applied to the positive electrode 9 and the negative electrode 10 in FIG. 3B under the control of the curing unit control unit 121 (for example, , The switch 14a is turned on), the ER fluid 7 is cured, and each sheet-like module 1A of each curing unit 1 is cured.

  Next, in step S9, the curing completion detection unit 110 determines whether the curing of each curing unit 1 has been completed (see FIG. 2D). That is, the curing completion detection unit 110 detects whether the curing of each curing unit 1 has been completed. When the control unit 108 determines that the curing of each curing unit 1 has not been completed based on the detection information from the curing completion detection unit 110, the process returns to step S8. When the control unit 108 determines that the curing of each curing unit 1 has been completed based on the detection information from the curing completion detection unit 110, the process proceeds to the next step S10.

  In step S10, each contact portion 2 is expanded (see FIG. 2E). That is, the air pump 20 of FIG. 4B is driven by the control of the contact part control unit 122 to supply air into the space 17 of each contact part 2 through the valve 19 and each of the contact parts 2. The expansion part 15 is expanded, and the internal pressure of each contact part 2 is increased.

  Next, in step S11, the gripping force detection unit 105 determines whether or not the gripping force generation operation has been completed (see FIG. 2E). That is, the gripping force detection unit 105 detects whether or not the gripping force generation operation for generating the gripping force by the internal pressure of the contact portion 2 between the gripping object 5 and the curing unit 1 is completed. When the control unit 108 determines that the operation of generating the gripping force is not completed based on the detection information from the gripping force detection unit 105, the process returns to step S10. When the control unit 108 determines that the generation operation of the gripping force is completed based on the detection information from the gripping force detection unit 105, the series of gripping operations is ended.

  Note that the step of contracting each contact portion 2 in step S2 may be completed before the start of the operation of closing each finger portion 3 in step S6. In the flowchart of FIG. 10A described above, the second step is used. However, the present invention is not limited to this, and the gripping operation can be performed in the order of the other three types of flowcharts shown in FIGS. 10B to 10D.

  Specifically, in FIG. 10B, the step of contracting each contact portion 2 in step S2 may be performed after step S3 in which all the finger portions 3 are opened. In this way, when the contact portion 2 is inflated, the force that makes the contact portion 2 move from the bent state to the non-bent state, that is, the extended state can be used for the opening operation of the finger portion 3. The opening operation of the part 3 can be performed more quickly, and the finger part 3 can move quickly.

  Moreover, in FIG. 10C, you may make it perform the process which shrink | contracts each contact part 2 of the said step S2 before step S1 which makes each hardening part 1 a soft state. By doing so, the force that causes the abutting portion 2 to change from the bent state to the non-bent state, that is, the extended state, by making the hardened portion 1 soft after the abutting portion 2 contracts is applied to the finger portion 3. Will not join.

  Also, in FIG. 10D, in the step S5 in which the approach detecting unit 102 determines whether or not the approach operation of the robot hand 100 with respect to the grasped object 5 is completed in the step of contracting each contact portion 2 in step S2. It may be performed later. In this way, when the contact portion 2 is contracted, the force for deforming from the non-bent state, that is, the extended state can be used for the closing operation of the finger portion 3, so that the closing operation of the finger portion 3 is performed quickly. be able to.

  The grip release operation of the robot hand 100, that is, the release operation will be described in detail below.

  The gripping operation of the robot hand 100 is realized as shown in FIGS. 2A to 2E and FIG. 11A under the control of the control unit 108.

  First, in step S21, each contact portion 2 is contracted (see FIG. 2A). That is, the air pump 20 of FIG. 4B is stopped by the control of the contact part control unit 122, the air in the space 17 of each contact part 2 is discharged from the valve 19, and each expansion part of each contact part 2 is discharged. 15 is shrunk and the internal pressure of each contact part 2 is reduced.

  Subsequently, in step S22, each hardening part 1 is made into a soft state (refer FIG. 2A). In other words, as described with reference to FIGS. 3A and 3B, FIGS. 6A and 6B, FIGS. 7A and 7B, the sheet-like modules 1A of the curing units 1 are softened. For example, when the ER fluid 7 is used for each curing unit 1, voltage application from the power source 14 to the positive electrode 9 and the negative electrode 10 in FIG. 3B is removed by the control of the curing unit control unit 121 (for example, The switch 14a is turned off), and the ER fluid 7 is softened to soften the respective sheet-like modules 1A of the respective hardened portions 1.

  Next, in step S23, all the finger parts 3 are opened (see FIG. 2B). That is, under the control of the finger control unit 123, the air pump 25 of FIG. 5 is stopped, the air in the space 26 is discharged from the valve 24, and each finger 3 is returned to the non-bent state.

  Next, in step S24, the follow-up action detection unit 104 detects whether or not all the finger parts 3 are separated from the grasped object 5, that is, as shown in FIGS. 14A to 14F. To do. The control unit 108 detects whether or not all the finger units 3 are separated from the grasped object 5 based on the detection information from the follow-up motion detecting unit 104, and all the finger units 3 are not separated from the grasped object 5. If it is determined, the process returns to step S23. On the other hand, when the control unit 108 determines that all the finger units 3 are separated from the grasped object 5 based on the detection information from the leveling motion detection unit 104, the process proceeds to the next step S25.

  In step S25, the robot hand 100 is moved in a direction away from the grasped object 5. That is, the central part (for example, base part 4) of the robot hand 100 in which all the finger parts 3 are opened via the manipulator 6 by driving the manipulator driving part 101 with the three finger parts 3 opened. Is moved away from the object to be grasped 5.

  Next, in step S26, the approach detection unit 102 determines whether or not the robot hand 100 is still in contact with the grasped object 5, that is, as shown in FIGS. . That is, the approach detection unit 102 detects whether or not the robot hand 100 is still in contact with the grasped object 5. When the control unit 108 determines that the robot hand 100 is still in contact with the grasped object 5 based on the detection information from the approach detection unit 102, the process proceeds to step S27. On the other hand, when the control unit 108 determines that the robot hand 100 is not in contact with the grasped object 5 based on the detection information from the approach detection unit 102, the series of opening operations is terminated. .

  In step S27, after all the finger parts 3 are further opened, the process returns to step S25, and step S25 is executed. That is, under the control of the finger control unit 123, the air pump 25 of FIG. 5 is stopped, the air in the space 26 is discharged from the valve 24, and each finger 3 is returned to the non-bent state.

  Note that the step of contracting each contact portion 2 in step S21 may be performed at any time. In the flowchart of FIG. 11A described above, the first step is used, but the present invention is not limited to this. The opening operation is also possible in the order of the other three types of flowcharts shown in FIG. 11D.

  Specifically, in FIG. 11B, the step of contracting each contact portion 2 in step S21 may be performed after step S2 of making each of the cured portions 1 in a soft state. In this way, it is possible to quickly release the grip. That is, the hardened portion 1 becomes soft and the gripping force output from the contact portion 2 cannot be supported, so that no force is applied to the gripped object.

  In FIG. 11C, the step of contracting each contact portion 2 in step S21 may be performed after step S24 for detecting whether all the finger portions 3 are separated from the grasped object 5. In this way, the same effect as in FIG. 11B can be obtained.

  Moreover, in FIG. 11D, you may make it perform the process of contracting each contact part 2 of the said step S21 last. In this way, the same effect as in FIG. 11B can be obtained.

  According to the above embodiment, the number of parts can be reduced by eliminating the need for the rotary connecting portion, and the structure can be simplified, and the hand shape is not controlled by the actuator position, but the hardness of the hardened portion. It is possible to realize a robot hand 100 that can perform simple control such as control and can grip objects to be gripped in various shapes.

  That is, the robot hand 100 is connected to the base portion 4 of the robot hand 100 and is arranged so that at least one pair is opposed to each other, and can be driven relative to the base portion 4 such as a bending operation or a pinching operation. 3 and continuously arranged on the outer periphery or outer surface (opposite surface of the object to be grasped) of the finger part 3 so as to cover all the movable points of each finger part 3, and the hardness is kept low and high while maintaining the shape. It can be controlled so that it can be reversibly transferred to and from the rigid state. It can be bent at any point in the soft state (low-rigid state), and even under external force in the hard state (high-rigid state). A plurality of fingers 100a each including a hardened portion 1 that is capable of holding a shape and an abutting portion 2 that is arranged on the outer periphery inside the hand of the hardened portion 1 and that can expand and contract are provided. Robot C Is a de-100. In the gripping operation of the robot hand 100 according to such a configuration, first, each curing unit 1 is controlled to be in a soft state (low rigidity state), and then pressed against the outer periphery of the gripping object 5 by the operation of the finger unit 3. Is deformed passively, and is controlled so as to be cured into a hard state (high rigidity state) after the deformation. After the curing, the contact portion 3 expands to be interposed between the gripping object 5 and the cured portion 1. Gripping can be performed by generating a gripping force. In this way, by arranging the respective hardened portions 1 as described above, the robot hand 100 can grasp the object 5 to be grasped by the rigidity of the hardened hardened portion 1 against the external force and the gripping force output from the contact portion 3. Holding is possible.

  Further, by adopting the structure as described above, holding of the finger shape against the gripping force or external force during the gripping operation that has been conventionally performed using the driving force of the finger is performed by the member rigidity of the cured hardened portion 1. Can do. Thereby, in addition to the solution of the conventional problem, the driving force of the finger 3 can be made lower than the conventional driving force.

  In addition, this invention is not limited to the said embodiment, It can implement in another various aspect.

  For example, in the robot hand 100 described in FIGS. 1A to 1C, the fingers 100 a including the finger part 3, the hardened part 1, and the contact part 2 are arranged on both sides of the base part 4. As a modified example of the first embodiment, as shown in FIGS. 16A and 16B, the finger 100 a composed of the finger part 3, the hardened part 1, and the contact part 2 is arranged only on one side of the base part 4. It may be a structure possessed by. 2A to 2E, the object 5 to be grasped is sandwiched between the base portion 4 and the three abutting portions 2, and the gripping and releasing operations are performed similarly to the first embodiment in FIG. 1. This is realized by the change of 1 to a hard state, the change to a soft state, and the expansion and contraction of the contact portion 2.

  Further, in the robot hand 100A in which the finger 101a is arranged only on one side shown in FIGS. 16A and 16B, the base portion 4 that presses one side of the gripping target object 5 is opposed to the gripping target object 5 as shown in FIGS. You may comprise so that it may have the inclined surface 4a as shown to 17B, or the curved surface 4b of side circular arc shape as shown to FIG. 18A and FIG. 18B. Thus, when the base part 4 including the inclined surface 4a grips the columnar or cylindrical gripping object 5, the base part 4 has a flat surface other than the inclined surface 4a and the inclined surface 4a (for example, the gripping object). 5c) (a surface perpendicular to the contact / separation direction of 5) and 4c can be brought into contact with the object 5 to be grasped, so that the object 5 to be grasped is supported at one point only on a plane having no inclined surface 4a. A reliable grip can be performed. Similarly, in the base part 4 including the curved surface 4b, for example, the gripping object 5 is made of a material that is easily slidable with respect to the base part 4 because of the feature that the slope gradually increases in the side surface arc shape of the curved surface 4b. Even if there is, gripping can be performed more reliably.

  Further, as still another modification of the first embodiment, the robot hand 100 illustrated in FIGS. 1A to 1C has, for example, a width of a finger 100b on one side of the base portion 4 as illustrated in FIGS. 19A to 19B. May be configured to be larger than the width of the other finger 100a. By adopting such a wide structure, the force between the fingers 100a and 100b can be received oppositely, so that the gripping force can be appropriately applied to the gripping object 5.

  Further, as still another modification of the first embodiment, as shown in FIGS. 20A to 20B, the thickness of the finger 100c on one side of the base portion 4 is configured to be larger than the thickness of the other finger 100a. Also good. For example, the thickness of the contact portion 2 of the finger 100c can be configured to be larger than the thickness of the contact portion 2 of the other finger 100a. With such a configuration, for example, the upper finger 100a in a state where the finger 100a on one side of the base portion 4 in FIGS. 20A to 20B is positioned on the upper side and the finger 100c on the other side is positioned on the lower side. When a gripping method in which a force is applied in a specific direction of the robot hand 100, such as gripping the gripping target object 5 toward the lower finger 100c, is used, stronger gripping can be realized.

  As various modifications of the first embodiment, the shape of each contact portion 2 is not limited to the first embodiment, and can be implemented in various modes as follows.

  That is, as for the shape of each contact part 2, as shown in FIG. 21, the expansion part 15a may be arranged elongated in the width direction, and a plurality of the expansion parts 15a may be arranged at intervals in the longitudinal direction. With such an arrangement, the gripping object 5 that has irregularities in the longitudinal direction of the abutting portion 2 can be brought into contact more accurately by expansion and reliably gripped.

  Further, as shown in FIG. 22, the inflatable portions 15b may be elongated in the longitudinal direction, and a plurality of inflatable portions 15b may be disposed at intervals in the width direction. With such an arrangement, it is possible to more reliably abut against the grasped object 5 having unevenness in the width direction of the abutting portion 2 by expansion more accurately and perform reliable grasping.

  Further, as shown in FIG. 23, the size of the inflatable portion 15c changes toward the fingertip (as it goes obliquely to the upper right in FIG. 23) (for example, the diameter of the hollow circular inflatable portion 15c decreases). You may arrange. By disposing the inflatable portions 15c of various sizes, it is possible to reliably perform gripping even when the gripping target object 5 has complex irregularities.

  Further, as shown in FIG. 24, the expansion portion 15d may be arranged so that its arrangement density increases as it goes toward the fingertip (as it goes obliquely to the upper right in FIG. 24). By increasing the arrangement density of the fingertips, it is possible to perform more reliable gripping, particularly in gripping using only the fingertips such as a picking operation.

  As still another modification of the first embodiment, as shown in FIGS. 25A and 25B, the finger part 3 and the hardened part 1 can move relative to each other and maintain contact with each other. It may be configured to be engaged and held so as to be able to. Specifically, for example, the hardened portion 1 has an inverted trapezoidal convex portion 1p on a surface facing the finger portion 3, and the finger portion 3 has a convex portion 1p fitted on the surface facing the hardened portion 1. The convex part 1p and the concave part 3p are slidable with respect to each other in the longitudinal direction (paper surface penetration direction in FIG. 25B) and perpendicular to the longitudinal direction (FIG. 25B). (Up and down direction) is engaged so as not to be extracted. By constituting in this way, peeling of hardened part 1 from finger part 3 (for example, hardened part 1 peels from finger part 3 in the up-and-down direction of Drawing 25B) can be prevented.

  It is to be noted that, by appropriately combining any of the various embodiments, the effects possessed by them can be produced.

  By using the robot hand and the robot hand control device of the present invention, it becomes possible to grip objects of various shapes with a simple structure and simple control. Therefore, it can be expected to be used not only as a robot hand and a robot hand control device for industrial robots used in factories, but also as a robot hand and a robot hand control device used for home manipulators.

1 is a schematic side view of a robot hand according to a first embodiment of the present invention. FIG. 3 is a schematic front view of the robot hand according to the first embodiment of the present invention. 1B is a schematic side view of the robot hand when gripping a gripping object having a shape different from that of the gripping object of FIG. 1A. FIG. Explanatory drawing which shows the outline | summary of the holding | grip operation | movement in the robot hand concerning the said 1st Embodiment of this invention. Explanatory drawing which shows the outline | summary of the holding | grip operation | movement in the robot hand concerning the said 1st Embodiment of this invention. Explanatory drawing which shows the outline | summary of the holding | grip operation | movement in the robot hand concerning the said 1st Embodiment of this invention. Explanatory drawing which shows the outline | summary of the holding | grip operation | movement in the robot hand concerning the said 1st Embodiment of this invention. Explanatory drawing which shows the outline | summary of the holding | grip operation | movement in the robot hand concerning the said 1st Embodiment of this invention. The perspective view which shows the outline | summary of the hardening part using the ER fluid in which the hardness can be arbitrarily controlled in the robot hand according to the first embodiment of the present invention. The top view which shows the outline | summary of the said hardening part in the robot hand concerning the said 1st Embodiment of this invention. Sectional drawing of the III-III line of FIG. 3B. The perspective view of the contact part which used air as a pressure fluid as a holding | grip force output part in the robot hand concerning the said 1st Embodiment of this invention. The schematic block diagram of the said contact part as a grip force output part in the robot hand concerning the said 1st Embodiment of this invention. The schematic diagram of the finger part in the robot hand concerning the 1st embodiment of the present invention. The schematic plan view of the hardening part using MR fluid in which the hardness can be arbitrarily controlled in the robot hand according to the modified example of the first embodiment of the present invention. Sectional drawing of the VI-VI line of FIG. 6A. The schematic plan view of the hardening part using the clay in the robot hand concerning another modification of the said 1st Embodiment of this invention which can control hardness arbitrarily. Sectional drawing of the VII-VII line of FIG. 7A. The figure which shows the structure of the whole robot hand concerning the said 1st Embodiment of this invention. The figure which shows the structure of the whole robot hand concerning the modification of the said 1st Embodiment of this invention. 4 is a flowchart of a gripping operation of the robot hand according to the first embodiment. The flowchart of the holding | grip operation | movement of the robot hand concerning the modification of the said 1st Embodiment. The flowchart of the holding | grip operation | movement of the robot hand concerning another modification of the said 1st Embodiment. The flowchart of the holding | grip operation | movement of the robot hand concerning another modification of the said 1st Embodiment. 4 is a flowchart of an opening operation of the robot hand according to the first embodiment. The flowchart of the open | release operation | movement of the robot hand concerning the modification of the said 1st Embodiment. The flowchart of the releasing operation | movement of the robot hand concerning another modification of the said 1st Embodiment. The flowchart of the open | release operation | movement of the robot hand concerning another modification of the said 1st Embodiment. The block diagram which shows the control structure for implement | achieving operation | movement of the robot hand concerning the said 1st Embodiment. The front view which shows the said robot hand structure which has an approach detection part which detects that the robot hand concerning the said 1st Embodiment approached the holding | grip target object. The side view which shows the said robot hand which has the said approach detection part of FIG. 13A. The front view which shows the said robot hand structure which has an approach detection part which detects that the robot hand concerning the modification of the said 1st Embodiment approached the holding | grip target object. The side view which shows the said robot hand which has the said approach detection part of FIG. 13C. The front view which shows the said robot hand structure which has an approach detection part which detects that the robot hand concerning another modification of the said 1st Embodiment approached the holding | grip target object. The side view which shows the said robot hand which has the said approach detection part of FIG. 13E. The front view which shows the said robot hand structure which has an approach detection part which detects that the robot hand concerning another modification of the said 1st Embodiment approached the holding | grip target object. The side view which shows the said robot hand which has the said approach detection part of FIG. 13G. The front view which shows the said robot hand structure which has a motion detection part which detects that the robot hand concerning the said 1st Embodiment completed the motion. FIG. 14B is a side view showing the robot hand having the tracing motion detection unit of FIG. 14A. The front view which shows the said robot hand structure which has a movement detection part which detects that the robot hand concerning the modification of the said 1st Embodiment completed the movement operation. The side view which shows the said robot hand which has the said tracing motion detection part of FIG. 14C. The front view which shows the said robot hand structure which has a motion detection part which detects that the robot hand concerning another modification of the said 1st Embodiment completed the motion. The side view which shows the said robot hand which has the said tracing motion detection part of FIG. 14E. The front view which shows the said robot hand structure which has a gripping force detection part which detects that the robot hand concerning the said 1st Embodiment completed gripping force generation | occurrence | production. The side view which shows the said robot hand which has the said holding | grip force detection part of FIG. 15A. The front view which shows the said robot hand structure which has a holding | grip force detection part which detects that the robot hand concerning the modification of the said 1st Embodiment completed holding | grip force generation | occurrence | production. The side view which shows the said robot hand which has the said holding | grip force detection part of FIG. 15C. The schematic front view of the robot hand concerning the modification of the said 1st Embodiment. FIG. 16B is a schematic side view of the robot hand of FIG. 16A. The schematic front view of the robot hand concerning another modification of the said 1st Embodiment. FIG. 17B is a schematic side view of the robot hand of FIG. 17A. The schematic front view of the robot hand concerning another modification of the said 1st Embodiment. FIG. 18B is a schematic side view of the robot hand of FIG. 18A. The schematic front view of the robot hand concerning another modification of the said 1st Embodiment. FIG. 19B is a schematic side view of the robot hand of FIG. 19A. The schematic front view of the robot hand concerning another modification of the said 1st Embodiment. FIG. 20B is a schematic side view of the robot hand of FIG. 20A. The perspective view of the contact part of the robot hand concerning the modification of the said 1st Embodiment of this invention. The perspective view of the contact part of the robot hand concerning another modification of the said 1st Embodiment of this invention. The perspective view of the contact part of the robot hand concerning another modification of the said 1st Embodiment of this invention. The perspective view of the contact part of the robot hand concerning another modification of the said 1st Embodiment of this invention. The side view of the robot hand concerning another modification of the said 1st Embodiment of this invention. FIG. 25B is a schematic sectional view taken along line BB in FIG. 25A. The figure which shows a 1st prior art example. The figure which shows a 2nd prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Curing part 1A, 1B, 1C Sheet-like module 2 Contact part 3 Finger part 4 Base part 4a Inclined surface 4b Curved surface 5 Grasping object 6 Manipulator 7 ER fluid 8 Insulating sheet 9 Positive electrode 10 Negative electrode 11 Outer peripheral thin film 12 Curing Peripheral film 13 Power line 14 Power supply 15 Expansion section 16 Non-expansion section 17 Air flow path 18 Air flow path 19 Valve 20 Air pump 21 Non-stretchable section 22 Stretchable section 23 Air flow path 24 Valve 25 Air pump 31 Magnetic body Sheet 32 Non-magnetic sheet 33 Non-magnetic sheet 34 MR fluid 35 Magnetic body 36 Electromagnet 37 Electromagnet drive power supply 41 Non-moisture permeable sheet 42 Clay 43 Moisture permeable sheet 44 Air flow path 45 Air flow path 46 Valve 47 Dry air input Pump 48 Steam input pump 49 Exhaust port 51 Rotating link 52 Wire 53 Drive unit 54 Wire 55 Bar Net 56 Base part 61 Contact part 62 Grasping part 63 Parallel link 64 Base part 71 Contact sensor 72 Image sensor 72A Image processing part 73 Distance sensor 74 Force sensor 75 Contact sensor 76 Pressure gauge 77 Image sensor 77A Image processing part 78 Distance measurement Sensor 100, 100A Robot hand 100a Finger 101 Manipulator drive unit 102 Approach detection unit 103 Contact detection unit 104 Follow-up motion detection unit 105 Gripping force detection unit 106 General control unit 107 Manipulator control unit 108 Control unit 109 Hand control unit 110 Curing completion detection unit 111 Curing unit driving unit 112 Contact unit driving unit 113 Finger unit driving unit 121 Curing unit control unit 122 Contact unit control unit 123 Finger unit control unit

Claims (9)

A base part;
A plurality of finger portions disposed on the base portion so as to face each other and bendable;
By disposing at least one of the plurality of finger portions on the surface on the gripping side of the object to be gripped, and bending from the low rigidity state that can be bent according to the one finger portion, Rigidity imparting part capable of reversibly transitioning between a high rigidity state in which the rigidity is higher than the low rigidity state and the bent shape can be maintained in a bent state;
A contact portion that is disposed on a surface of the gripping object on the gripping side of the gripping object, is in contact with the gripping object, is inflatable, and can be contracted so as to be separated from the gripping object. Robot hand characterized by   The robot hand according to claim 1, wherein the rigidity imparting unit is disposed so as to cover all the movable points of the finger unit.   The robot hand according to claim 1, wherein the contact portion is disposed so as to cover all of the movable points of the finger portion.   The robot hand according to any one of claims 1 to 3, wherein each of the plurality of finger portions includes the rigidity imparting portion and the contact portion.   The rigidity imparting portion uses a Bingham fluid or a functional fluid as a material capable of reversibly controlling the hardness between the low rigidity state and the high rigidity state while maintaining the shape. The robot hand according to claim 1. The rigidity imparting part is a curing part capable of reversibly controlling the hardness between the low rigidity state and the high rigidity state while maintaining the shape using ER fluid or ER gel,
The hardened portion has a pair of electrodes facing each other in the insulating thin film, an insulating spacer is disposed between the pair of electrodes in the thin film, and the ER is placed in a space between the electrodes in the thin film. The robot hand according to any one of claims 1 to 4, wherein the robot hand is constituted by a sheet-like structure enclosing a fluid or an ER gel, and the sheet-like structure is formed by laminating a plurality of layers.   The rigidity imparting portion is a curing portion that can reversibly and arbitrarily control the hardness between the low rigidity state and the high rigidity state while maintaining the shape using the MR fluid, The hardened portion generates a magnetic field in the MR fluid enclosed between the magnetic members by arranging a pair of magnetic members facing each other and connecting each end of the magnetic members through an electromagnet. The robot hand according to claim 1, wherein the robot hand is configured to cause the   The rigidity imparting unit can reversibly control the hardness between the low-rigidity state and the high-rigidity state using a dry-curing clay that is a Bingham fluid while maintaining the shape. It comprises a curing part, and the curing part is a sheet-like module in which the clay is disposed between the moisture-impermeable film and the moisture-permeable film arranged to face each other, so that the moisture-impermeable film is on the outside. The moisture permeable films are arranged so as to face each other and are formed into a hollow sheet shape, and water vapor or dry air is passed through the sheet hollow space between the opposed moisture permeable films to form the low rigidity state or the high rigidity state. It controls so that it may become. The robot hand as described in any one of Claims 1-4 characterized by the above-mentioned. A control device for a robot hand that controls the operation of the robot hand according to any one of claims 1 to 8,
In the gripping operation, first, the rigidity imparting portion is controlled to be softened to the low rigidity state,
After that, the contact portion is passively deformed together with the finger portion and the hardened portion by pressing the contact portion against the outer surface of the grasped object by the bending operation of the finger portion,
It is controlled so that the rigidity applying portion is cured to the high rigidity state while maintaining the deformed state after the deformation,
A control device for a robot hand that grips the gripping object by the robot hand by generating a gripping force between the gripping object and the curing portion by expanding the contact portion after curing.

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