JP5777331B2 - Finger unit and gripping device - Google Patents

Description

  The present invention relates to a finger unit and a gripping device used for gripping an article that is a gripping target in a robot or the like.

  Conventionally, a robot hand or the like as disclosed in the following Patent Documents 1 and 2 is provided as a gripping device for gripping an object to be gripped by a robot or the like.

  The robot hand disclosed in Patent Document 1 enables a gripping operation to grip an object placed on a plane so as to lift it, and includes a finger body that can perform a bending operation for gripping an object. It has been configured. This robot hand is provided with a claw portion provided with an elastic body at a tip portion of the finger body on the abdomen side, and the claw portion is provided between the object and the floor surface on which the object is arranged. It can be inserted.

  The robot hand disclosed in Patent Document 2 intends to reduce the pressure when gripping a gripping object by increasing the gripping force in the palm direction, and is the root that is the base side of the finger portion. It is set as the structure provided with the link and the front end link connected to the root link. In this robot hand, a concave curved portion is provided in a region closer to the root side than the intermediate portion of the tip link, and the pressure acting by gripping is directed toward the palm direction, so that the pressure toward the center of the grasped object is reduced. Reduced.

JP 2010-36328 A JP 2009-214269 A

  However, the above-described prior art robot hand cannot properly grip the object to be gripped. Specifically, since the robot hand disclosed in Patent Document 1 is configured to insert and lift the claw portion between the floor surface and the grasped object, the tip portion of the claw portion is the grasped object. In the case of contact with the claw, excessive pressure acts on the contact portion with the claw portion, which may damage or damage the object to be grasped. Further, even if the contact between the tip of the claw portion and the object to be grasped can be avoided, there is a problem that the object to be grasped is mounted on the nail portion and the grasping becomes unstable.

  Further, in the robot hand disclosed in Patent Document 2, since the curved portion is provided on the base side of the tip link, the stress acting on the gripping object is likely to be directed toward the palm side, and the gripping object is correspondingly increased. It is assumed that the applied pressure is somewhat relaxed. However, when the outer surface shape of the grasped object is a complicated shape, such an effect is not necessarily expected.

  Therefore, an object of the present invention is to provide a finger unit and a gripping device that can be gripped appropriately even if the shape is complicated or a gripping object that is easily damaged or damaged.

The finger unit of the present invention provided to solve the above-described problem is
A finger unit that is used in a gripping device capable of gripping a gripping object and includes a finger pad mechanism and a base member that supports the finger pad mechanism,
The finger pad mechanism part is
A surface layer part capable of surface contact with the gripping object;
An intermediate member that can be deformed following the surface layer, and
A support member configured to be able to be pressed from the back surface side against the surface layer portion and movable on the base member to one side or the other side in the longitudinal direction of the surface layer portion;
An actuator capable of applying a moving power to the support member,
The intermediate member and the support member are arranged between the base member and the surface layer portion. And according to the distribution of the pressure acting on the surface of the surface layer part in contact with the gripping object, the support member is moved to one side or the other side in the longitudinal direction of the surface layer part by the actuator . While moving on the base member, the distribution of pressure acting on the grasped object as the grasped object is grasped and the direction of the pressure are controlled. Note that “pressing against the surface layer portion from the back surface side” corresponds to a mode in which the support member abuts or presses against the surface layer portion from the back surface side, for example, in the form of compressing the intermediate member.

According to the above configuration, when the gripping object comes into contact with the surface layer portion of the finger pad mechanism part and pressure acts, the posture of the surface layer part changes along the gripping object with the support member as a fulcrum, The surface layer portion is in a state of wrapping the object to be grasped. Therefore, the contact area between the surface layer portion of the finger pad mechanism and the grasped object is increased, and it is possible to avoid local concentration of pressure acting on the grasped object side. That is, according to the above configuration, before the surface layer portion is changed in posture by the support member, the surface layer portion and the intermediate member are changed in shape so as to follow the shape of the grasped object, and the pressure acting on the surface of the grasped object is locally changed. Can be suppressed. In addition, the intermediate member provided between the surface layer portion and the base member is deformed following the surface layer portion, thereby suppressing a local increase in pressure (surface pressure) acting on the surface of the object to be grasped. It is possible to suppress a change in posture due to an external force (disturbance) applied to the grasped object by reliably grasping the grasped object so that the surface layer wraps around the grasped object. Therefore, the gripping device using the finger unit of the present invention can easily cause trauma to the gripping object even when the gripping object has a complicated shape or is easily damaged. It is possible to grab stably without giving. In addition, when the surface layer part and the object to be gripped come into contact with each other, the surface layer part may be supported by the support member when the surface pressure of the surface layer part is excessively increased at a position deviated from the support position of the surface layer part to be supported by the support member. At the same time, the posture of the surface layer portion can be changed so that the surface layer portion opposite to the biased position with the support position as the center is pressed against the object to be grasped. As a result, the surface pressure of the pressed portion of the surface layer portion increases, the surface pressure of the surface layer portion of the portion where the surface pressure has increased excessively decreases, and the surface pressure applied to the grasped object of the surface layer portion is made uniform. be able to. From the above, the gripping device of the present invention can be suitably used for a humanoid robot hand or the like. Further, the support member is movable on the base member to one side or the other side in the longitudinal direction of the surface layer portion, and the position of the support member is determined according to the distribution of pressure acting on the surface of the surface layer portion. Since it can be moved, the pressure balance in the surface layer part and the posture of the surface layer part can be changed smoothly and accurately, so that the object to be grasped can be brought along the surface of the surface layer part. . Therefore, according to the configuration described above, the surface layer portion and the gripping object can be brought into surface contact with each other, and the local increase in pressure acting on the gripping object can be further alleviated. That is, the actuator moves the support member in the direction along the surface layer portion according to the distribution of the pressure acting on the surface of the surface layer portion in accordance with the contact with the object to be gripped. It is possible to control the distribution of pressure acting on the object to be grasped and the direction of the pressure.

  Moreover, in the finger unit having the above-described configuration, it is preferable that the intermediate member includes a buffer unit that relieves pressure acting on the surface layer portion. According to this, it is possible to relieve the pressure acting on the gripping object at the intermediate member and reduce the local increase of the pressure acting on the gripping object side by the reaction, It can be gripped with a more appropriate force.

  According to such a configuration, when a gripping object is gripped, a local increase in pressure acting on the surface of the gripping object is suppressed, and the distribution of the magnitude of pressure acting on the gripping object side by reaction is made uniform. And it becomes possible to disperse the direction in which the pressure is applied.

  In the finger unit configured as described above, it is preferable that the support member has viscosity or / and elasticity. By adopting an elastic support member, it is possible to prevent a sudden increase in surface pressure when the gripping force is increased in order to grip the object to be gripped. Moreover, by adopting a viscous member as the support member, it is possible to suppress the vibration of the object to be grasped and the vibrational change in the surface pressure acting on the object to be grasped. Therefore, according to the configuration described above, it is possible to grip without damaging the gripping object.

  Further, in the finger unit configured as described above, the surface layer portion includes a plurality of irregularities extending linearly in the same direction on the surface, and the irregularities are provided so as to extend in the longitudinal direction of the finger unit. It is preferable. According to this, the gripping object comes into surface contact with the convex part formed on the surface of the surface layer part, and the corner (edge) of the gripping object can be stored in the concave part. Moreover, each unevenness | corrugation which comprises a surface layer part is the structure where the small piece of the surface layer member which has a convex part was arranged in the surface, and the recessed part may be comprised by the clearance gap between each small piece. At that time, it is desirable that the small pieces are connected to each other by a film, a wire, or a string-like material. According to this, each piece connected by a membrane, a wire, a string-like object, or the like moves slightly in conjunction with the movement (shape change) of the surface layer portion in contact with the object to be grasped, and wraps the object to be grasped. Is possible. Furthermore, each piece is free without being restrained while being connected. Thereby, it becomes possible to further wrap the object to be grasped.

  In the finger unit configured as described above, the surface layer portion preferably has elasticity or viscoelasticity. According to this, it is possible to further alleviate the impact acting on the gripping object by gripping, and to prevent damage to the gripping object. In addition, it is preferable that a surface layer part does not plastically deform by the pressure which acts when hold | griping.

  Moreover, in the finger unit having the above-described configuration, it is preferable that a plurality of finger pad mechanisms are provided along the longitudinal direction of the finger unit. According to this, even if it is a gripping object having a complicated surface shape or a gripping object having a thickness, it is possible to grip the gripping object more carefully. In addition, it is possible to hold the support member in the finger pad mechanism provided at the tip of the finger unit on the tip side of the finger unit or by moving it to the tip side in a more tightly wrapped state. Become.

  Furthermore, it is a gripping device comprising a plurality of the finger units described in any of the above, and capable of gripping the gripping object by the plurality of finger units, wherein the plurality of finger units move in directions approaching and separating from each other. It is preferable that the gripping object is configured to be able to be gripped by moving objects to be gripped arranged in a space formed between the plurality of finger units in directions close to each other. That is, the gripping device of the present invention includes a plurality of finger units that can move in directions close to and away from each other, and can grip a gripping object disposed in a space formed between the finger units. The finger unit includes a finger pad mechanism part that contacts the gripping object and a base member that supports the finger pad mechanism part, and the finger pad mechanism part includes the gripping object. A surface layer part that can be brought into surface contact with the surface layer part, an intermediate member that can be deformed following the surface layer part, and a support member that can be pressed against the surface layer part from the back side, and the base member and the The intermediate member and the support member are arranged between the surface layer portion. Then, when the pressure acts on the surface layer portion in contact with the gripping object, the posture of the surface layer portion can change with a support member that presses the surface layer portion from the back side as a fulcrum. . Note that “pressing against the surface layer portion from the back surface side” corresponds to a mode in which the support member abuts or presses against the surface layer portion from the back surface side, for example, in the form of compressing the intermediate member.

  According to the present invention, the object to be grasped can be grasped so as to be wrapped as if a person grasps it with a finger according to the above-described principle, and therefore, it is easy to be complicated in shape, damaged or damaged. It is possible to provide a finger unit and a gripping device that can properly grip even a gripping object.

It is the top view which showed notionally the grasping device concerning one embodiment of the present invention. (A) is a perspective view which shows the finger unit employ | adopted in the holding | grip apparatus shown in FIG. 1, (b) is AA sectional drawing of (a). It is sectional drawing which shows the structure of a finger pad mechanism part. (A), (b) is sectional drawing which respectively shows the state which the pressure acted on the finger pad mechanism part by hold | gripping a holding | grip target object. It is sectional drawing which shows the state which hold | gripped the holding target object with the finger unit provided with the finger pad mechanism part shown in FIG. (A) is sectional drawing which shows the 1st modification of a finger pad mechanism part, (b) is sectional drawing which shows the state which the pressure acted on the finger pad mechanism part shown to (a) by hold | gripping a holding | grip target object, (C) is sectional drawing which shows the state which pressure acted on the finger pad mechanism part shown to (a) by holding | griping a holding | grip target object with the moved support member. (A)-(d) is sectional drawing which shows the structure of the finger pad mechanism part which concerns on a 2nd modification , a 3rd modification, a 1st reference example, and a 2nd reference example , respectively. (A) is an enlarged view of the surface layer part employ | adopted in the finger pad mechanism part shown in FIG. 3, (b)-( d ) is an enlarged view which shows the modification of (a), respectively. (A)-(d) is sectional drawing which shows the finger pad mechanism part which concerns on a 6th reference example from a 3rd reference example, respectively. (A)-(c) is sectional drawing which shows the finger pad mechanism part which concerns on a 7th reference example, a 4th modification, and a 5th modification , respectively. (A) is sectional drawing which shows the finger unit provided with the finger pad mechanism part which concerns on an 8th reference example , (b) is a top view which shows the holding | gripping apparatus which employ | adopted the finger unit of (a). (A) is sectional drawing which shows the finger unit provided with the finger pad mechanism part which concerns on a 9th reference example , (b) is sectional drawing which shows the finger pad mechanism part which concerns on a 10th reference example .

  A finger unit according to an embodiment of the present invention and a gripping device using a plurality of such finger units will be described with reference to the drawings.

  As shown in FIG. 1, the gripping device 100 includes a control device 12 and a plurality (four in this embodiment) of finger units 20 (20a, 20b, 20c, 20d) that are controlled by the control device 12. The object to be grasped W placed in the space formed between the finger units 20a, 20b, 20c, and 20d can be grasped. The finger units 20 a, 20 b, 20 c, and 20 d are respectively arranged in the vertical and horizontal directions on the paper surface of FIG. 1 with respect to the space formed between the finger units 20. Each of the finger units 20a, 20b, 20c, and 20d moves linearly in the X direction or the Y direction along the rail 16 by operating an actuator (not shown), and each finger unit 20a, 20b, 20c is moved. , 20d can be moved closer to and away from the center of the space formed between them.

  As shown in FIG. 2, the finger unit 20 has a longitudinal shape and includes a base member 22 and a finger pad mechanism 24. The base member 22 functions as a core material of the finger unit 20 and is formed of a material that does not cause permanent deformation due to a reaction force when gripping the gripping target object W, such as resin, metal, or wood. . Further, the base member 22 is configured by a cylindrical body such as a cylindrical body, but may be a columnar body.

  The finger pad mechanism 24 is a mechanism disposed on the outer peripheral side of the base member 22, and is a portion that makes surface contact with the grasped object W. In addition, a plurality of finger pad mechanism parts 24 (three in the present embodiment) are arranged in the longitudinal direction of the finger unit 20 and are arranged to be independently operable. Specifically, the finger unit 20 includes a region corresponding to a portion from a fingertip to a first joint, a region corresponding to a portion from a first joint to a second joint, and a second joint to a third joint. The finger pad mechanism portion 24 is provided in a form corresponding to each of the regions corresponding to the reaching portions.

  The finger pad mechanism 24 includes a surface layer 26, an intermediate member 28, a support member 30, and a pressure sensor 32, as shown in FIGS. 3 shows a cross section of only the space side portion formed between the finger units 20a, 20b, 20c, and 20d shown in FIG. Illustration is omitted.

  The surface layer portion 26 is provided on the most surface side in the finger pad mechanism portion 24, and holds the grasped object W arranged in the space formed between the finger units 20a, 20b, 20c, and 20d shown in FIG. This is a layer in surface contact with the object to be grasped W when grasping. Further, the surface layer portion 26 has a thin and flexible streaky surface layer member 26a (corresponding to the “small piece” described in the means for solving the problem) in substantially the same direction (this embodiment). In FIG. 1, the plurality of the surface layer portions 26 are arranged in the Z direction (that is, the surface layer portion 26 is an aggregate of a plurality of surface layer members 26a). The surface layer member 26a can be formed of a flexible material such as polyvinyl chloride or polyurethane. For example, natural rubber, styrene butadiene rubber (SBR), nitrile butadiene rubber (NBR), butadiene rubber material ( In addition to rubber materials such as BR), isoprene rubber (IR), butyl rubber (IIR), halogenated butyl rubber (X-IIR), and chloroprene rubber (CR), metal such as bamboo, wood, or piano wire or spring member It may be formed.

  Further, as shown in FIG. 2 and FIG. 8A, the surface layer portion 26 has a plurality of cylindrical surface layer members 26a arranged in the substantially same direction on the surface of the intermediate member 28, thereby providing unevenness 34 (FIG. 3, FIG. 4, etc. (not shown in some drawings) are formed. The unevenness 34 is constituted by a convex portion 34a and a concave portion 34b, and is formed so as to surround substantially the entire circumference of the finger unit 20 (that is, as described above so as to surround substantially the entire circumference of the finger unit 20). A surface layer member 26a is disposed). Further, as shown in FIG. 2, the convex portion 34 a and the concave portion 34 b are provided so as to extend in a streak shape in the longitudinal direction of the finger unit 20. In FIG. 8A, the convex portion 34a corresponds to a circular cross-sectional portion (more specifically, an upper semicircular portion that can function as a convex portion of the circular cross-sectional shape portion), and the concave portion 34b. Corresponds to a valley-like portion formed between the convex portions 34a, 34a arranged in the circumferential direction of the finger unit 20.

  Since the unevenness 34 is formed on the surface 26b of the surface layer portion 26 as described above, when the gripping target object W is gripped, the gripping target object W is in line contact with the convex portion 34a and the gripping target object W is formed in the concave portion 34b. Can be stored. Thereby, not only the gripping object W having a complicated shape can be gripped so as to be wrapped, but also the gripping object W that is soft and easily damaged or easily deforms is damaged. It is possible to grip the envelope without equating. In the present embodiment, the configuration in which the surface layer portion 26 is exposed is illustrated, but another cover can be attached to the outside of the surface layer portion 26.

  The intermediate member 28 is a layer provided between the base member 22 and the surface layer portion 26. As shown in FIG. 4, the intermediate member 28 can be deformed following the surface layer portion 26 when a pressure is applied to the surface layer portion 26 as the object to be grasped W is gripped. Specifically, the intermediate member 28 is formed of a material having elasticity and / or viscoelasticity. For example, natural rubber, styrene butadiene rubber (SBR), nitrile butadiene rubber (NBR), butadiene rubber material (BR), Rubber materials such as isoprene rubber (IR), butyl rubber (IIR), halogenated butyl rubber (X-IIR), chloroprene rubber (CR), and the like produced by adding additives that exhibit high damping to these rubber materials It can be formed of a material such as a damping rubber composition or polyurethane. By adopting such a configuration, the pressure acting on the surface layer portion 26 when gripping the gripping target object W is relieved in the intermediate member 28, and the local increase of the pressure acting on the gripping target object W side is prevented. Is possible.

  The support member 30 is a member having a function of controlling a pressure distribution mainly acting on the surface layer portion 26. By changing the position of the support member 30, the distribution state of the pressure acting on the surface layer portion 26 can be changed. The support member 30 is preferably made of a resin or the like having a viscosity or / and elasticity, and more preferably formed of a member that is not easily plastically deformed even when an assumed external force is applied. As shown in FIGS. 3 and 4, the support member 30 in the present embodiment is provided such that the surface in contact with the base member 22 is a base end portion 30 a and the tip end portion 30 b protrudes toward the intermediate member 28 side. It is a protruding member (in this embodiment, a member provided in a ring shape around the base member 22). The height of the support member 30 (the length from the base end portion 30a to the tip end portion 30b) is configured to be smaller than the thickness of the intermediate member 28 described above. Therefore, as shown in FIG. 3, in the state where the pressure in the thickness direction (compression direction) of the finger pad mechanism portion 24 is not acting on the surface layer portion 26, the distal end portion 30 b of the support member 30 is the surface layer portion 26. It is not in contact with the back surface 26c side. Further, as shown in FIG. 5, the support member 30 in the finger pad mechanism 24 located at the fingertip is provided in the vicinity of the tip (fingertip) of the base member 22.

  Here, depending on the height of the support member 30, the movable angle of the posture of the surface layer portion 26 is determined. Further, the portion obtained by subtracting the height of the support member 30 from the height of the intermediate member 28 causes the intermediate member 28 to exhibit a spring action and a damper action (spring / damper action), and follows the shape of the grasped object W. Thus, it is used as a movable margin for changing the shape and for recovering the position and orientation of the grasped object W. The height of the support member 30 is adjusted to an optimum height in consideration of these points.

  On the other hand, as shown in FIG. 4, when the pressure described above is applied to the surface layer portion 26, the intermediate member 28 is compressed and deformed, and the distal end portion 30 b of the support member 30 is against the surface layer portion 26. (The intermediate member 28 is interposed between the back surface 26c of the surface layer portion 26 and the support member 30 and the back surface 26c of the surface layer portion 26 are not in contact with each other) The member 28 is pressed). Therefore, when a pressure acts on the surface 26b of the surface layer portion 26 due to contact with the grasped object W, the posture (tilt or curved state) of the surface layer portion 26 can be changed with the support member 30 as a fulcrum.

  The support member 30 is provided so as to function as a fulcrum when momentarily balancing the force applied to the surface layer portion 26 in a distributed manner when the object to be grasped W is grasped. When it is desirable to balance momentarily in a state where the surface layer portion 26 is in a horizontal posture, the support member 30 is disposed at a position where the substantially central portion of the surface layer portion 26 can be supported. In addition, when it is desirable to balance momentarily in a state where the posture (inclination or bending state) of the surface layer portion 26 is inclined or curved, as shown in FIG. The support member 30 is moved or arranged so that the position in which the protrusion direction of the support member 30 deviates without being opposed to each other (see the arrow in FIG. 4A).

  Further, as shown in FIG. 4B, when the support member 30 is arranged on the fingertip side with respect to the center of the finger pad mechanism 24 and pressure is applied in the direction of the arrow in FIG. The position of the portion 26 is tilted so that the base side of the finger unit 20 (the side opposite to the fingertip) approaches the base member 22, and the contact position with respect to the grasped object W is the base side of the finger unit 20 (opposite to the fingertip) from the support member 30. Therefore, it is possible to prevent the grasped object W from falling off. As described above, by disposing the support member 30 on the fingertip side, the base side of the surface layer portion 26 is easily inclined so as to approach the base member 22, and the direction of the pressure acting on the grasped object W is the root direction of the finger unit 20. Therefore, the movement of the grasped object W in the fingertip direction of the finger unit 20 can be further suppressed.

  Therefore, it is preferable that the supporting member 30 is configured to be movable along the surface layer portion 26 (for example, along the longitudinal direction of the finger unit 20 (the left-right direction in FIGS. 3 and 4)). In this way, the surface layer portion is configured such that the support member 30 can move to an appropriate position according to the position of the pressure acting on the surface 26b of the surface layer portion 26 and the pressure distribution by the contact with the grasped object W. 26 can be changed in posture along the grasped object W. Thereby, when gripping the gripping target object W, the surface layer portion 26 is in surface contact with the gripping target object W (surface contact is considered as the surface layer portion 26, but when the surface layer member 26 a alone is viewed as a line, It is possible to control the distribution of the pressure acting on the object to be grasped W and the direction of the pressure mechanically.

  The intermediate member 28 is preferably made of a soft material such as an open cell sponge. The intermediate member 28 has a function of copying the shape of the surface layer portion 26 to the shape of the grasped object W, and a target when the grasped object W deviates from a target posture or a stable grasping position and posture due to disturbance or the like. A function to generate a force and a restoring moment to restore the posture or a stable gripping position and posture is exhibited.

  As shown in FIG. 3, the pressure sensors 32 are provided at predetermined intervals along the base member 22 in the longitudinal direction of the finger unit 20. The pressure sensor 32 may be disposed at any position as long as the pressure can be detected, but the surface pressure that prevents the surface 26b of the surface layer portion 26 from scratching or permanently deforming the grasped object W. It is preferable to arrange so as to obtain an output characteristic that makes it possible to determine whether or not the user is gripping within the range. In this embodiment, it arrange | positions so that it may distribute to right and left with the neutral point of the surface layer part 26 as a boundary, Thereby, the direction of the force applied to the attitude | position of the surface layer part 26 or the holding | grip target object W can be estimated. . In FIG. 4, the pressure sensor 32 is omitted for convenience of explanation.

  Next, the operation of the gripping device 100 will be described. As shown in FIG. 1, the gripping device 100 includes finger units 20a and 20b arranged above and below the page of FIG. 1, and finger units 20c and 20d arranged on the left and right of the page of FIG. Each finger unit 20 operates on the basis of a command transmitted from. When the gripping object W is arranged in a space formed between the finger units 20a to 20d, the gripping device 100 is configured so that the finger units 20a and 20b are in the Y direction and the finger units 20c and 20d are in response to a command from the control device 12. Moves in the X direction and gathers on the center side of the space formed between the finger units 20a to 20d. Thereby, the surface layer part 26 of each finger unit 20a-20d will be in the state which contacted the surface of the holding | grip target object W. FIG.

  When the support member 30 can move along the surface layer portion 26 by receiving power from an actuator (not shown), for example, when each finger unit 20a to 20d comes into contact with the grasped object W, the pressure acting on the finger pad mechanism portion 24 Is detected by the pressure sensor 32. Based on the detection result, the control device 12 moves the support member 30 to change the pressure balance in the surface layer portion 26. That is, the support member 30 moves to an appropriate position (position shifted from each other so that the pressure and the support member 30 do not face each other) as a fulcrum for changing the posture of the surface layer portion 26 along the grasped object W. Thereby, as shown in FIG. 5, the surface layer part 26 of the finger pad mechanism part 24 provided in the finger units 20a to 20d is inclined and curved along the outer surface of the grasped object W, respectively. The support member 30 is not necessarily limited to one that can be moved by receiving power, but may be one that can be moved by pressure applied to the finger pad mechanism 24.

  In more detail, taking the state of FIG. 5 as an example, in the second and third finger pad mechanisms 24 from the fingertip side of the finger unit 20, the support member 30 exists substantially at the center, and the moment balance point (support Point) is set in the vicinity of the center. Further, the first finger pad mechanism 24 from the fingertip side is set so that the support member 30 is located at a position biased toward the fingertip side, and the moment balance point (support point) is biased toward the fingertip side from the approximate center. It is in a state. Accordingly, in the first finger pad mechanism 24 shown in FIG. 5 from the fingertip side, the sum of the distributed pressures on the left side of the moment balance point (support point) in the support member 30 is larger than the sum of the distributed pressures on the right side. Thus, a force can be generated toward the base side of the finger unit 20. Moreover, it can suppress that the holding | grip target object W moves to a fingertip direction by this.

  Further, when the surface layer portion 26 of the finger pad mechanism 24 provided in the finger units 20a to 20d is inclined and curved along the outer surface of the grasped object W (see FIG. 5), the intermediate member 28 is provided. Is deformed so as to follow a shape change of the surface layer portion 26 such as an inclination or a curve. As a result, the local increase in the pressure R acting on the gripping object W accompanying gripping is alleviated and the gripping object W is gripped. 5, only the space side portion formed between the finger units 20a to 20d shown in FIG. 1 in the finger pad mechanism 24 is shown, and the other illustrations are omitted.

  On the other hand, when releasing the gripping object W gripped in the space formed between the finger units 20a to 20d, the control device 12 moves the finger units 20a to 20d in a direction away from the space. Thereby, the pressure which acted on each finger pad mechanism part 24 is cancelled | released, and the intermediate member 28 returns to the original state as shown in FIG. Following this, the surface layer portion 26 returns to a state substantially parallel to the base member 22.

  As described above, in the gripping device 100 according to the present embodiment, when pressure is applied to the surface layer portion 26 of the finger pad mechanism 24 of each finger unit 20 when gripping the gripping target object W, the surface layer is used with the support member 30 as a fulcrum. The posture of the unit 26 changes so as to follow the grasped object W. As a result, the surface layer portion 26 and the gripping target object W are brought into surface contact with each other, the contact area with the gripping target object W is increased, and the pressure acting on the gripping target object W side is prevented from being concentrated locally. be able to. Therefore, according to the gripping device 100, not only the gripping object W having a complicated shape can be gripped so as to be wrapped, but also the gripping target object W that is soft and easily damaged or whose shape tends to collapse is affected. The gripping target object W can be gripped without being damaged.

  In the finger pad mechanism 24 described above, the intermediate member 28 is formed of a material having elasticity and / or viscoelasticity, deforms following the surface layer 26, and has a pressure acting on the grasped object W side. Local rise can be suppressed. As a result, it can be gripped as if a person is gripping with a finger, that is, can be gripped within a surface pressure range that does not damage or permanently deform the gripping object W.

  In the gripping device 100 of the present embodiment, for example, as shown in FIG. 2, a plurality of finger pad mechanisms 24 are provided in the longitudinal direction of the finger unit 20 like a human finger. For this reason, even if the gripping target object W has a complicated surface shape, the gripping target object W is gripped so as to be wrapped more carefully, that is, the gripping target object W is not damaged or permanently deformed. It is possible to grip within the range.

  In addition, although this invention is described in said preferable embodiment, this invention is not restrict | limited only to it. For example, various embodiments are possible without departing from the spirit and scope of the invention, as described below as variations.

≪First modification of finger pad mechanism part≫
In the present embodiment, the intermediate member 28 is a soft material such as a sponge having an open cell structure formed of a rubber material such as natural rubber or styrene butadiene rubber, or a viscoelastic or elastic material such as a high-damping rubber composition. However, the present invention is not limited to this. For example, the finger pad mechanism 241 shown in FIG. 6 can be used. Hereinafter, the finger pad mechanism 241 will be described. In addition, about the structure, the function, and the effect of the surface layer part 261, the support member 301, and the base member 221, since it is the same as that of the surface layer part 26, the support member 30, and the base member 22 in order, detailed description is abbreviate | omitted. .

The finger pad mechanism 241 has substantially the same configuration as the finger pad mechanism 24 described above, but has a buffer means 40 in the space 281 between the surface layer part 261 and the base part 221 instead of the intermediate member 28. Is different. The buffer means 40 is composed of a combination of a spring 42 and a damper 44 having linear or non-linear characteristics, and is disposed on both the one end side and the other end side in the longitudinal direction of the finger pad mechanism 241 . The posture is supported so that the posture can be changed to a posture or shape along the outer shape of the grasped object W. For the case of such a configuration, similarly to the case of forming the intermediate member 28 of a material having viscoelastic or elastic as the finger unit 20 described above, the shape of the space 281 to follow the surface portion 261 It is possible to make the distribution state of the pressure acting on the surface layer portion 261 gentle by changing. Further, when the buffer means 40 functioning as the intermediate member 28 is configured by the spring 42 and the damper 44 as described above, it is possible to simplify the apparatus configuration while ensuring a sufficient space for operating the support member 301. It becomes possible. Further, by adopting the configuration as in this modification, it is possible to improve the durability as compared with the case where a sponge-like member is employed as the intermediate member 28.

Further, in the finger pad mechanism 241, like the finger pad mechanism 24, the support member 301 can freely move in the direction along the surface layer part 261, and the position of the pressure acting on the surface of the surface layer part 261. The balance of the pressure in the surface layer portion 261 can be changed by moving the support member 301 according to the distribution. Therefore, the finger pad mechanism 241 can accurately and smoothly change the posture of the surface layer part 261 along the surface of the grasped object W. Therefore, if the finger pad mechanism 241 is used, the surface layer portion 261 and the grasped object W can be reliably brought into surface contact, and the local increase in pressure acting on the grasped object W can be further alleviated.

≪Second modification of finger pad mechanism part≫
The finger pad mechanism 24 described above is configured such that the support member 30 is made of resin or metal, but the present invention is not limited to this, and has viscosity and / or elasticity instead of the support member 30. It is also possible to adopt a structure having a function as a buffer means, a function for improving the degree of translational freedom, a function as a spring element and a damper element, and the like. Specifically, the finger pad mechanism 242 shown in FIG. 7A can be used. Hereinafter, the finger pad mechanism 242 will be described in detail. In addition, about the structure, function, and effect of the surface layer part 262, the base member 222, the buffer means 402, and the spring 422 and the damper 442 constituting the buffer means 402, the above-described surface layer part 26, the base member 22, and the buffer means 40 are sequentially described. Since it is the same as the spring 42 and the damper 44 constituting the buffer means 40, a detailed description thereof will be omitted.

  The support member 302 is obtained by wrapping an open cell viscoelastic material, a gas, a liquid, a gel-like substance, or the like with a flexible bag or film, and the surface layer portion 262 is the same as the support member 30 described above. Is disposed in a space 282 between the base portion 222 and the base portion 222. By adopting such a support member 302, in addition to the same effect as the case where the support member 30 described above is used, a pressure acting from the surface layer portion 262 side by gripping the gripping object W is applied to the support member 302. It is possible to relieve the pressure, and the gripping target object W can be gripped softer, that is, the gripping target object W can be gripped without being damaged or permanently deformed.

≪Third modification of finger pad mechanism part≫
From the same knowledge as the second modification described above, the support member is replaced with the support member 302 of the second modification described above, and the configuration like the support member 303 in the finger pad mechanism 243 shown in FIG. It can be. Hereinafter, the finger pad mechanism 243 of the third modified example having the support member 303 will be described. In addition, about the structure of the spring 423 and the damper 443 which comprise the surface layer part 263, the base member 223, the buffer means 403, and the buffer means 403, a function, and an effect, in order, the surface layer part 26, the base member 22, the buffer means 40, which were mentioned above. Since it is the same as the spring 42 and the damper 44 which comprise the buffer means 40, detailed description is abbreviate | omitted.

  The finger pad mechanism portion 243 is configured such that a portion on the base end portion 303a side and a portion on the distal end portion 303b side are formed by separate members, and a spring and a damper are built in between them. In this case, as shown in FIG. 7B, the tip 303b is always in contact with the back side of the surface layer 263. Even in the case of such a configuration, as in the case of using the support member 301 described above, a support member in which part of the pressure is disposed in the space 283 between the surface layer portion 263 and the base portion 223. At 303, the pressure can be relieved, and the object to be grasped W can be gripped.

≪First reference example of finger pad mechanism part≫
In the above embodiment, an example in which the intermediate member 28 and the support member 30 are configured as separate members has been described. However, as described above, both the intermediate member 28 and the support member 30 have viscoelasticity or elasticity. In this case, it is possible to replace with a single member (hereinafter also referred to as “intermediate / support member 464”) having both functions of the intermediate member 28 and the support member 30. Specifically, a configuration like a finger pad mechanism 244 shown in FIG. Hereinafter, the configuration, function, and effect of the finger pad mechanism 244 will be described in detail. In addition, since the surface layer part 264 and the base member 224 which the finger pad mechanism part 244 has are the same as the surface layer part 26 and the base member 22 mentioned above, respectively, detailed description is abbreviate | omitted.

  The intermediate / support member 464 employed in the finger pad mechanism 244 is a gummy material having viscoelasticity, or an air spring-like material enclosing a fluid or gas. When the intermediate / support member 464 is provided in the space 284 between the surface layer portion 264 and the base member 224, it can be provided over the entire back surface of the surface layer portion 26 as in the intermediate member 28 in the above embodiment. As shown in FIG. 7 (c), in the space 284 between the surface layer portion 264 and the base member 224, at a predetermined interval in the longitudinal direction of the finger pad mechanism portion 244 (FIG. 7 (c) right and left direction on the paper surface). It may be provided. In addition, in the finger pad mechanism 244 shown in FIG. 7C, the configuration in which the surface layer portion 264 is connected to the intermediate / support member 464 arranged in parallel is illustrated, but the intermediate point between the intermediate / support members 464 is illustrated. The surface layer portion 264 may be cut.

≪Second reference example of finger pad mechanism part≫
In the finger pad mechanism 244 of the first reference example , the configuration in which the intermediate / support members 464 are provided at predetermined intervals in the longitudinal direction is exemplified. However , the structure like the finger pad mechanism 245 of FIG. It is also possible. In addition, since the surface layer part 265 and the base member 225 which the finger pad mechanism part 245 has have the same structure, function, and effect as the surface layer part 264 and the base member 224 of the first reference example described above in order. Detailed description is omitted.

The intermediate / support member 465 employed in the finger pad mechanism 245 has a width (longitudinal direction of the finger pad mechanism 245 (the left-right direction in FIG. 7D)) of the intermediate / support member 464 described above. ) Are large, and are arranged side by side in the space 285 between the surface layer portion 265 and the base member 225 with almost no gap. Also in the case of such a configuration, as in the case of the first reference example , each intermediate / support member 465 absorbs the pressure acting from the grasped object W side and alleviates the local increase in pressure. Is possible. In addition, in the finger pad mechanism part 245 shown in FIG. 7D, the configuration in which the surface layer part 265 is connected to the intermediate / support member 465 arranged in parallel is illustrated, but the intermediate point between the intermediate / support members 465 is illustrated. The surface layer portion 265 may be cut.

≪Third reference example of finger pad mechanism part≫
The surface layer part 26 which the finger pad mechanism part 24 of the said embodiment has , and the surface layer parts 261 to 265 of the finger pad mechanism parts 241 to 245 according to the first to third modifications , the first reference example, and the second reference example. is either were those integrally formed, it may be divided into a plurality of regions. Hereinafter, the finger pad mechanism 246 having such a configuration will be described. Note that the configurations, functions, and effects of the intermediate member 286, the support member 306, and the base member 226 are the same as those of the intermediate member 28, the support member 30, and the base member 22 described above, and thus detailed descriptions thereof are omitted.

  As shown in FIG. 9A, the surface layer portion 266 provided in the finger pad mechanism 246 has a plurality of regions (5 regions in the illustrated state) in the longitudinal direction of the finger pad mechanism 246 (left and right direction in FIG. 9A). ) And can be independently transformed. Therefore, when the gripping target object W is gripped and pressure is applied to the surface layer part 266, the posture is such that the surface layer part 266 follows the surface of the gripping target object W compared to the case where the finger pad mechanism part is not divided. Easy to change.

≪Fourth reference example of finger pad mechanism part≫
Similarly to the surface layer portion 266 of the third reference example , when the surface layer portion is divided into a plurality of regions, the finger pad mechanism portion is configured like a finger pad mechanism portion 247 shown in FIG. It is possible. The finger pad mechanism 247 is configured so that the support member 307 having the same configuration and function as the support member 302 of the second modification described above is disposed below each region of the surface layer portion 267 (that is, inside the intermediate member 287). Have. The intermediate member 287 is made of a material having viscoelasticity or elasticity like the intermediate member 28 described above. The base member 227 is the same as the base member 22 described above. By adopting such a configuration, it is possible to receive the pressure applied to each region of the surface layer portion 267 at each support member 307 provided corresponding thereto. As shown in FIG. 9B, by disposing the pressure sensors 327 at equal intervals on both sides of the support member 307, the position and orientation of the surface layer portion 267 can be estimated from the outputs of the pressure sensors 327. Note that the arrangement of the pressure sensors 327 is not necessarily equal, and the position and orientation of the surface layer portion 267 can be estimated if the intervals of the pressure sensors 327 are known.

≪Fifth reference example of finger pad mechanism part≫
As shown in FIG. 9C, the finger pad mechanism 248 according to the fifth reference example has a surface layer divided into a plurality of regions in the same manner as the surface layer portions 266 and 267 of the third reference example and the fourth reference example. Part 268. The configurations and effects of the intermediate / support member 468 and the base member 228 of the finger pad mechanism 248 are the same as those of the intermediate / support member 464 and the base member 224 of the finger pad mechanism 244 according to the first reference example described above. . The intermediate / support member 468 is disposed in a space 288 between the surface layer portion 268 and the base member 228. By adopting such a configuration, the inclination of the surface layer portion 268 can be flexibly changed, which is particularly effective when gripping the gripping object W having relatively small unevenness.

≪Sixth reference example of finger pad mechanism part≫
As shown in FIG. 9D, the finger pad mechanism 249 according to the sixth reference example is a surface layer divided into a plurality of regions in the same manner as the surface layer portions 266 to 268 of the third reference example to the fifth reference example. Part 269 is provided. The configurations and effects of the intermediate / support member 469 and the base member 229 of the finger pad mechanism 249 are the same as those of the intermediate / support member 465 and the base member 225 according to the second reference example described above. The intermediate / support member 469 is disposed in a space 289 between the surface layer portion 269 and the base member 229. Even with such a configuration, as with the finger pad mechanism unit 24 and finger pad mechanism units 241 to 248 described above, the user grips the grip target object W as if it is gripped by a finger, in other words, the grip target. The object W can be gripped within a surface pressure range that does not damage or permanently deform the object W. In addition, with such a configuration, the surface layer portion 269 can be uniformly deformed to the shape of the surface of the grasped object W. Therefore, when grasping the grasped object W having relatively gentle irregularities. Is particularly effective.

≪Seventh reference example of finger pad mechanism part≫
Finger pad mechanism portion 24 described above, as shown in FIG. 3, but are arranged the pressure sensor 32 to the position of the base end portion 30a of the support member 30, for example finger pad mechanism shown in Fig. 10 (a) It is good also as a structure like 250. Hereinafter, the finger pad mechanism 250 will be described. In addition, about the structure, function, and effect of the surface layer part 270, the base member 230, the intermediate member 290, the support member 500, and the pressure sensor 330, in order, the surface layer part 26, the base member 22, the intermediate member 28, the support member 30, Since it is the same as that of the pressure sensor 32, detailed description is abbreviate | omitted.

  In the finger pad mechanism 250, the pressure sensor 330 is disposed at a position on the distal end side of the support member 500 (in FIG. 10A, a position closer to the surface layer portion 270 than the distal end portion of the support member 500). By disposing the pressure sensor 330 at such a position, the deformation of the intermediate member 290 also affects the output of the pressure sensor 330, and the sensitivity is improved accordingly. Moreover, the distance from the surface layer part 270 to the pressure sensor 330 becomes shorter than the distance from the surface layer part 26 of the finger pad mechanism part 24 to the pressure sensor 32, and the improvement of the detection accuracy of the pressure sensor 330 by this is also anticipated. Therefore, when the support member 500 is movable, the support member 500 can be moved to a more accurate position. In addition, grip control using information transmitted from the pressure sensor 33 or posture control of the finger pad mechanism unit 250 using the support member 500 can be performed with higher accuracy.

≪Fourth modification of finger pad mechanism part≫
As a modification provided with the buffering means 411 similar to the buffering means 40 included in the finger pad mechanism 241 of the first modification described above, a configuration like a finger pad mechanism 251 shown in FIG. Is possible. Hereinafter, the finger pad mechanism 251 will be described. The configuration, function, and effect of the surface layer portion 271, the base member 231, the support member 501, and the pressure sensor 331 are the same as those of the surface layer portion 26, the base member 22, the support member 30, and the pressure sensor 32 described above in order. Detailed description will be omitted. Here, the support member 501, the buffer member 411, and the pressure sensor 331 are all disposed in a space 291 between the surface layer portion 271 and the base member 231.

  The buffer unit 411 includes a spring 431 and a damper 451. The pressure sensor 331 and the pressure sensor 332 are provided at the base end portion (end portion on the base member 231 side) of the spring 431 and the base end portion (end portion on the base member 231 side) of the damper 451, respectively. In the case of such a configuration, the pressure acting on the surface layer portion 271 is directly transmitted to the pressure sensor 331 and the pressure sensor 332 by transmitting the spring 431 and the damper 451, thereby further improving the pressure detection accuracy. It becomes possible to improve.

≪Fifth modification of finger pad mechanism part≫
Instead of the pressure sensors 32 and 331 shown in the above-described embodiment and the fourth modification , it is also possible to use a sensor 321 constituted by a linear motion potentiometer or a non-contact distance measuring sensor. Hereinafter, the finger pad mechanism 252 to which the sensor 321 configured by a direct acting potentiometer is applied will be described. Note that in the finger pad mechanism 252, the structure, function, and effect of the surface layer portion 272, the base member 232, the support member 502, and the buffering means 412 are sequentially described in the surface layer portion 26, the base member 22, the support member 30, and the buffer. Since it is the same as that of the means 40, detailed description is abbreviate | omitted.

  As shown in FIG. 10 (c), the finger pad mechanism 252 includes a sensor 321 configured by a linear motion potentiometer in a space 292 between the surface layer portion 272 and the base member 232. It is provided at a position adjacent to it. Also in the case of such a configuration, by grasping the characteristics of the spring 432 and the damper 452 in advance, the magnitude and distribution of the pressure can be accurately grasped similarly to the case where the pressure sensor 32 is used, It becomes possible to move the support member 502 to an appropriate position.

In addition, as a modified example of this modified example, like the above-described intermediate / support members 464, 465, 468, 469 of the finger pad mechanism parts 244, 245, 248, 249, or the support member 307 of the finger pad mechanism part 247, When the structure is such that it stays at a fixed position and supports the surface layer portions 264, 265, 268, 269 or 267 , it is not necessary to arrange a pressure sensor, and the device structure can be simplified accordingly. It becomes.

«Eighth Example of finger pad mechanism, as well as reference examples of the finger unit and the gripping device»
Like finger pad mechanism portion 24 shown in the above embodiment, although both are a structure in which a surface portion 26 over the entire circumference of the base member 22 such as a core material, have the following configurations Good . For example, like the finger pad mechanism 253 employed in the finger unit 201 shown in FIG. 11A, the intermediate member 293 and the support member 503 are provided so as to surround the entire circumference of the base member 233. The base layer 273 may be provided only on a part of the base member 233 in the circumferential direction.

  Hereinafter, the gripping device 101 including the finger unit 201 illustrated in FIG. 11A will be described with reference to the drawings. In the following description, the configuration, function, and effect of the surface layer portion 273, the intermediate member 293, the support member 503, the base member 233, and the rail 161 will be described in the order of the surface layer portion 26, the intermediate member 28, the support member 30, and the like. Since it is the same as that of the base member 22 and the rail 16, detailed description is abbreviate | omitted.

  As shown in FIG. 11B, the gripping device 101 is arranged such that each finger unit 201 has a portion where the surface layer portion 273 is provided and faces the center side of the gripping device 101. Along the direction along the center of the gripping device 101, and a direction away from the center. Thereby, the gripping device 101 can be gripped so as to wrap the gripping target object W in the same manner as the gripping device 100 shown in FIG.

«Reference Example of the ninth reference examples and finger unit of the finger pad mechanism»
Finger unit 20 and finger units 201 described above are all, was the columnar body fitted with finger pad mechanism portion 24,253 so as to surround the entire outer periphery of the base member 22,233, shown in FIG. 12 (a) It is good also as a structure like the finger unit 202. FIG. Hereinafter, the finger pad mechanism 254 and the finger unit 202 will be described in detail with reference to the drawings. In the following description, the structure, function, and effect of the surface layer portion 274, the intermediate member 294, the support member 504, and the base member 234 will be described in order, in the order of the surface layer portion 26, the intermediate member 28, the support member 30, and the base member 22. Therefore, the detailed description is omitted.

The finger pad mechanism 254 has the same configuration as the finger pad mechanism 24 described above. According to the finger pad mechanism 254, (1) deformation to follow the shape of the object to be grasped W, (2) object to be grasped, as in the case of employing the above-described embodiment, modification, and reference example There are effects such as maintaining the position and orientation of the object W, (3) relaxing the required accuracy of the position and orientation of the finger part in the grip control, and (4) relaxing the pressure distribution acting on the surface of the object W to be gripped. can get.

  The finger pad mechanism 254 is attached only to a part of the base member 234 in the circumferential direction, and the base member 234 is exposed at the other part. Also in the case of such a configuration, similarly to the gripping device 101 shown in FIG. 11B, by arranging each finger unit 202 so that the portion provided with the finger pad mechanism 254 faces the device center side. An effect similar to that of the gripping device 100 shown in FIG. 1 is obtained.

≪Tenth reference example of finger pad mechanism part≫
The above embodiment constitutes a base member 22 and the like by the tubular body or the columnar body, has been illustrated a structure in which a finger pad mechanism portion 24 or the like to the outer peripheral side, for example finger pad mechanism shown in FIG. 12 (b) It is good also as a structure like 255. Hereinafter, the finger pad mechanism portion 255 will be described. The configuration, function, and effect of the surface layer portion 275, the intermediate member 295, the support member 505, and the base member 235 are sequentially described above. Since it is the same as that of the member 30 and the base member 22, detailed description is abbreviate | omitted.

  The finger pad mechanism portion 255 is provided with a surface layer portion 275, an intermediate member 295, and a support member 505 on the surface of a base member 235 formed of a flat plate. The base member 235 can be configured by a plate having a flat surface, but in the example illustrated in FIG. 12B, the base member 235 is configured by a plate that is curved so that the surface is concave. As a result, the surface pressure can be made uniform as compared with the case where the surface is made flat, and gripping is performed so as to wrap more, that is, the gripping target W is not damaged or permanently deformed. It is possible to provide the finger pad mechanism 255 that can be gripped within the surface pressure range, and can be moved so that the gripping surface is moved while being gripped, that is, the gripping object W is gently gripped.

≪Modification of surface layer part≫
In the above embodiment, as shown in FIG. 8A, an example in which the unevenness 34 formed by the convex portion 34 a having a substantially circular cross section and the valley-shaped concave portion 34 b is provided on the surface 26 b of the surface layer portion 26. Although shown, the present invention is not limited to this, and the surface layer portion may not have the unevenness 34. In this case, the corners (edges) of the grasped object W are not absorbed in the recesses, but can be grasped so as to wrap the grasped object W.

  Further, even when the surface of the surface layer portion is uneven, the shape of the unevenness may be different from the above-described unevenness 34, and the surface layer portion 276 shown in FIGS. It is good also as a shape like the unevenness | corrugation 341-343 which -278 has. Also in such a case, the same effect as the surface layer part 26 or the unevenness | corrugation 34 mentioned above is acquired.

Specifically, as in the surface layer portion 276 shown in FIG. 8B, the cross-sectional shape has a concavo-convex portion 341 composed of a semicircular convex portion 341a and a valley-shaped concave portion 341b, or FIG. ), (D) surface layer portions 277 and 278 may include projections 342a and 343a having a rectangular cross-sectional shape and projections and depressions 342 and 343 including recesses 342b and 343b.

  When the unevenness 341 as shown in FIG. 8B is provided, the semicircular protrusion 341a is provided in the same manner as the case where the substantially circular cross-sectional protrusion 34a is provided as shown in FIG. 8A. , 341a can absorb the edge of the object W to be gripped by the valley-shaped recess 341b. 8C and 8D, when the convex portions 342a and 343a having a rectangular cross-sectional shape are provided, the contact area of the convex portions 342a and 343a with the gripping object W increases, and the gripping is performed. The pressure acting on the surface of the object W can be reduced. In the case where the surface layer portions 342 and 343 are formed of a material having flexibility, when the rectangular convex portions 342a and 343a are provided, the gripping object W is directly connected as shown in FIGS. 8C and 8D. By forming the contact portion in a concave shape, the gripping object W is brought into surface contact, and it is possible to disperse the pressure acting by the line contact with the convex portion 34a shown in FIG. Further, the local increase in pressure acting on the surface of the grasped object W can be further suppressed. Moreover, when providing a rectangular-shaped convex part like convex part 342a, 343a, it is preferable to curve the angle | corner of convex part 342a, 343a as shown in FIG.8 (c).

100, 101 Grasping device 20, 201, 202 Finger unit 22, 221-234 Base member 24, 241-255 Finger pad mechanism 26, 261-275 Surface layer 28, 281-296 Intermediate member 30, 301-303, 306, 307, 500 to 505 Support member 34, 341 to 347 Unevenness 464, 465, 468, 469 Intermediate / support member W Grasping object

Claims (8)

A finger unit that is used in a gripping device capable of gripping a gripping object and includes a finger pad mechanism and a base member that supports the finger pad mechanism,
The finger pad mechanism part is
A surface layer part capable of surface contact with the gripping object;
An intermediate member that can be deformed following the surface layer, and
A support member configured to be able to be pressed from the back surface side against the surface layer portion and movable on the base member to one side or the other side in the longitudinal direction of the surface layer portion;
An actuator capable of applying a moving power to the support member,
Between the base member and the surface layer portion, the intermediate member and the support member are arranged,
Depending on the distribution of the pressure acting on the surface of the surface layer portion in contact with the object to be grasped , the base is moved to one side or the other side in the longitudinal direction of the surface layer portion by the actuator. A finger unit that moves on a member and controls the distribution of pressure acting on the gripping object as the gripping object is gripped, and the direction of the pressure.   The finger unit according to claim 1, wherein the intermediate member includes a buffer unit that relieves pressure acting on the surface layer portion. The finger unit according to claim 2, wherein the buffer means is made of a material having elasticity or viscoelasticity.   The finger unit according to claim 1, wherein the support member has viscosity or / and elasticity. The surface layer portion has a plurality of irregularities extending in a streak shape in the same direction on the surface, and is disposed so as to surround substantially the entire circumference of the finger unit,
The finger unit according to any one of claims 1 to 4, wherein the unevenness is provided so as to extend in a longitudinal direction of the finger unit.   The finger unit according to claim 1, wherein the surface layer portion has elasticity or viscoelasticity.   The finger unit according to any one of claims 1 to 6, wherein a plurality of finger pad mechanisms are provided along a longitudinal direction of the finger unit. A gripping device comprising a plurality of finger units according to any one of claims 1 to 7, wherein the gripping object can be gripped by the plurality of finger units,
The plurality of finger units are
It is configured to be movable in a direction that is close to and away from each other, and can be gripped by moving a gripping object disposed in a space formed between the plurality of finger units in a direction that is close to each other. A gripping device characterized by being made.