JP2010000560A - Residual deformation thin object gripping device - Google Patents

Abstract

An object of the present invention is to automatically grip a cloth or the like with high probability without leaving damage, dirt or folds on the cloth or the like when the cloth or the like is flat on a floor surface or the like. It is another object of the present invention to provide a gripping apparatus that can reduce the manufacturing cost as much as possible.
The gripping devices 1 and 2 according to the present invention separate a hand part 21 by a first distance and hold a gripping mechanism to a position (first position) at which a lower finger part 21b contacts an edge part of a cloth CL or the like. Move 2A. Next, the apparatus brings the hand unit closer to the second distance. Subsequently, the apparatus moves the gripping mechanism to a position (second position) above and behind the first position, and brings the hand unit closer to the third distance. Thereafter, the apparatus moves the gripping mechanism to at least a position ahead of the second position in a state where the finger portions 21A are separated by an eleventh distance. And the apparatus makes a finger part approach to the 12th distance.
[Selection] Figure 1

Description

  The present invention relates to an automatic gripping device for residual deformable thin objects such as fabrics, films, and papers.

  In recent years, robots that can automatically handle fabric handling, for example, transporting fabric, stacking fabric, folding fabric, etc. from the apparel industry, cleaning industry, linen supply industry, welfare industry, medical industry, etc. The voice that awaits the development of is heard.

  By the way, in order to realize such a fully automatic handling of the fabric, it is first necessary to establish an automatic gripping technology for the fabric. Various proposals have been made to date regarding the automatic gripping technology of the fabric.

  For example, in the past, “a lifting gripper device (hereinafter referred to as“ first conventional device ”) that holds and lifts one fabric from a container in which a number of fabrics are placed at an arbitrary position” has been proposed (for example, Patent Document 1). And Patent Document 2). Specifically, this lifting gripper device is mainly composed of an automatic lifting mechanism and a gripper opening / closing mechanism (for example, an air chuck, a clip, or a tangs) attached to the end of the automatic lifting mechanism. .

  In the past, "a pair of hollow needles facing in opposite directions, an adhesive tape, and a fabric lifting device that lifts fabric using negative pressure (hereinafter referred to as" third conventional device ")" have been proposed (for example, And Patent Document 3).

  In the past, “two-finger parallel hand device (hereinafter referred to as“ fourth conventional device ”) that has two finger parts movable in the left-right direction and picks up the fabric with the two finger parts” or “closely arranged” A two-finger parallel hand device (hereinafter referred to as “fifth conventional device”) that has two rollers and rotates one of the rollers forward and reversely rotates the other roller to wind up the fabric has been proposed (hereinafter referred to as “fifth conventional device”). For example, refer nonpatent literature 1).

In the past, “a two-finger parallel hand mechanism that has two fingers that can move in the left-right direction and deforms the cloth into a mountain shape, and a cloth lifting hand mechanism that is inserted into the space under the cloth deformed to the mountain side and lifts the cloth. Have been proposed (refer to Non-Patent Document 2, for example).
JP 2002-321869 A Japanese Patent Laid-Open No. 7-231999 JP-A-7-68066 Fumiaki Osawa, 1 other person, trial manufacture of fingers for grasping laundry mixed with various fabrics and evaluation of grasp experiments, “Journal of the Robotics Society of Japan”, September 2001, Vol. 19, No. 6, p. 735-743 Eiji Wakamatsu, 2 others, Static analysis of bending deformation operation in thin plate manipulation, “The Japan Society of Mechanical Engineers, Proceedings C”, April 1997, Vol. 63, No. 608, p. 1102-1109

  However, the first conventional apparatus and the second conventional apparatus have a problem that the probability that the cloth can be lifted is not high when the cloth is flat on the floor surface or the bottom surface of the container. On the other hand, the third conventional device, the fourth conventional device, the fifth conventional device, and the sixth conventional device have a fairly high probability even when the fabric is flat on the floor surface or the bottom surface of the container. Can be lifted. However, the third conventional apparatus has a problem that the possibility of damaging the fabric or soiling the fabric cannot be denied. In addition, the fourth conventional device and the fifth conventional device have a problem that, depending on the type of the fabric, a severe crease is formed on the fabric, and the appearance of the fabric is impaired or the fabric is damaged. The sixth conventional apparatus has no problem of damaging the cloth, soiling the cloth, or crease the remaining deformable thin object, but requires two robot arms and two robot hands. There is a problem that it becomes extremely high.

  The problem of the present invention is that the residual deformable thin material such as fabric, film, paper, sheet, etc. exists in a flat state on the floor surface or the bottom surface of the container, or the like. The residual deformable thin object can be gripped automatically with a high probability and the manufacturing cost can be kept as low as possible without contaminating the thin object or making a crease in the residual deformable thin object. To provide an apparatus.

  A residual deformable thin object gripping apparatus according to a first aspect of the present invention is a residual deformable thin object gripping apparatus for gripping a residual deformable thin object, the residual deformable thin object gripping mechanism, a residual deformable thin object gripping mechanism moving mechanism, and a control device. Is provided. Here, “residual deformability” means a property of being deformed by receiving an external force and maintaining the deformed shape for a predetermined time or longer even when the external force is removed. In addition, the “residual deformable thin material” referred to here is, for example, a fabric, a film, paper, a sheet, or the like. In the present invention, the shape of the residual deformable thin object is not particularly limited, but if it is rectangular, the residual deformable thin object gripping device can be easily controlled. Moreover, in this invention, it is preferable that the thick part (for example, folding | turning part etc.) is formed in the edge of this residual deformable thin object. The residual deformable thin object gripping mechanism includes at least two hand portions and a second approaching / separating mechanism. The hand portion has a pair of finger portions and a first approach / separation mechanism. The pair of finger portions oppose each other. The first approaching / separating mechanism can move the pair of finger parts relative to each other along a surface including the opposing direction of the pair of finger parts (hereinafter referred to as “first surface”) to approach and separate the pair of finger parts. It is. The finger portion may be configured to slide along the first surface, or may be configured to open and close like a claw around a fulcrum. Further, the “relative movement” referred to here is to change the relative positional relationship between one finger part and the other finger part by moving at least one finger part along the first surface. . The second approaching / separating mechanism can move the hand part relatively on the same straight line along a direction orthogonal to the first surface (hereinafter referred to as “first direction”) to approach and separate the hand part. Note that “relative movement” herein refers to changing the relative positional relationship between one or more hand units and other hand units by moving at least one hand unit along the first direction. It is. As the first approach / separation mechanism and the second approach / separation mechanism, specifically, mechanisms such as a ball screw mechanism, an air cylinder mechanism, a motor cylinder mechanism, an electric slider mechanism, a belt slider mechanism, a linear slider mechanism, and a rack and pinion mechanism Is mentioned. These mechanisms are mainly composed of a drive source, a feed member, and a guide member. The ball screw mechanism is a slide moving mechanism that uses a motor as a drive source, a ball screw or a trapezoidal screw as a feed member, and an LM guide material or the like as a guide member, and moves by transmitting the rotation of the motor to the ball screw or the trapezoidal screw. This is a mechanism for sliding an object along a guide member such as an LM guide. The air cylinder mechanism is a slide movement mechanism that uses an air compressor as a drive source and a piston rod as a feed member and a guide member, and uses a direct movement of the piston rod to move a moving object attached to the piston rod. It is a mechanism for sliding. The motor cylinder mechanism is a slide moving mechanism that uses a motor as a drive source and a piston rod as a feed member and a guide member, and transmits the rotation of the motor to a ball screw to slide a moving object attached to the piston rod. It is a mechanism to make. The electric slider mechanism is a slide moving mechanism that uses a motor as a drive source, a ball screw or the like as a feed member, and an LM guide material or the like as a guide member, and transmits the rotation of the motor to the ball screw to move the moving object to the LM. It is a mechanism for sliding along a guide member such as a guide material. The belt slider mechanism is a slide movement mechanism that uses a motor as a drive source, a belt or a wire as a feed member, and an LM guide material or the like as a guide member, and transmits the rotation of the motor to the belt or wire to be moved. This is a mechanism for sliding an object along a guide member such as an LM guide material. The linear slider mechanism is a slide moving mechanism that uses a magnet as a drive source, the same feed member as a magnet, and an LM guide material or the like as a guide member. The linear slider mechanism slides and moves a moving object using the principle of a linear motor. It is a mechanism to make. The rack and pinion mechanism is a slide moving mechanism that uses a motor as a drive source, uses the rack and pinion as a feed member, and uses an LM guide material or the like as a guide member, and rotates the pinion by the rotation of the motor and is attached to the rack. This is a mechanism for sliding the moving object along a guide member such as an LM guide material. The residual deformable thin object gripping mechanism moving mechanism can move the residual deformable thin object gripping mechanism at least in the vertical direction and the front-rear direction. The control device has a control unit. The control unit performs first control, second control, third control, fourth control, fifth control, sixth control, and seventh control. In the first control, the control unit controls the second approach / separation mechanism so that the hand unit is separated by a first distance. In the second control, after the first control or during the first control, the residual deformable thin object is moved to a position where one of the fingers contacts the edge of the residual deformable thin object (hereinafter referred to as “first position”). The residual deformable thin object gripping mechanism moving mechanism is controlled to move the gripping mechanism. In order to realize such control, the residual deformable thin object is placed at a specified position on the dedicated stand, or the edge of the residual deformable thin object is residually deformed based on image data from a digital stereo camera. A technique such as causing the thin object gripping device to recognize may be used. In the third control, after the second control, the control unit controls the second approach / separation mechanism so that the hand unit approaches the distance shorter than the first distance (hereinafter referred to as “second distance”). In the fourth control, after the third control, the residual deformable thin object gripping mechanism moves the residual deformable thin object gripping mechanism to a position above and below the first position (hereinafter referred to as “second position”). Control the moving mechanism. In the fifth control, after the fourth control or during the fourth control, the control unit moves the second approach / separation mechanism so as to approach the hand unit to a distance shorter than the second distance (hereinafter referred to as “third distance”). Control. Note that the third distance is determined in consideration of the deformed shape of the residual deformable thin object. In the sixth control, after the fourth control or the fifth control, the control unit moves the residual deformable thin object gripping mechanism at least a position in front of the second position (hereinafter referred to as “the second” after the finger part is separated by the eleventh distance). The residual deformable thin object gripping mechanism moving mechanism is controlled so as to be moved to “three positions”. The timing for creating the “state in which the finger portions are separated by the eleventh distance” may be any timing as long as it is before the sixth control. In the seventh control, after the sixth control, the control unit controls the first approach / separation mechanism so that the finger unit approaches a distance shorter than the eleventh distance (hereinafter referred to as “the twelfth distance”).

  When the residual deformable thin object gripping operation is started by the control device, the residual deformable thin object gripping apparatus first moves the hand unit away from the first distance and moves the residual deformable thin object gripping mechanism to the first position. At this time, the lower surface of the lower finger portion is in contact with the edge of the residual deformable thin object. Next, this residual deformable thin object gripping device brings the hand portion closer to the second distance. At this time, if the friction between the lower surface of the lower finger portion and the upper surface of the residual deformable thin object is sufficiently high, or the lower finger portion presses the residual deformable thin object downward. If so, the residual deformable thin object is deformed into a mountain shape (in side view) by the proximity of the hand portions. That is, a mountain-shaped space (hereinafter referred to as “yamagata space”) is formed under the mountain-shaped portion of the residual deformable thin object. Subsequently, the residual deformable thin object gripping device moves the residual deformable thin object gripping mechanism to the second position, and brings the hand portion closer to the third distance. That is, at this time, the residual deformable thin object gripping mechanism is positioned at an upper position in front of the mountain-shaped portion of the residual deformable thin object in a state where the hand parts are close to each other. At this time, the residual deformable thin object keeps its deformed shape due to its properties. Further, the third distance at this time, that is, the approach distance of the hand portion, must be a distance that allows the lower finger portion to be inserted into the mountain space. The second position is preferably “a height position at which the lower finger portion is inserted into the angle space when the residual deformable thin object gripping mechanism is advanced as it is”. Thereafter, the residual deformable thin object gripping apparatus moves the residual deformable thin object gripping mechanism to the third position in a state where the finger portions are separated by an eleventh distance. Note that the eleventh distance must be a distance where the chevron portion of the residual deformable thin object enters. Further, the third position must be “a position at which the pair of finger portions sandwich the mountain-shaped portion of the remaining deformable thin object”. And this residual deformable thin object holding | grip apparatus makes a finger part approach to 12th distance. That is, at this time, the residual deformable thin object gripping device grips the residual deformable thin object at the finger portion. The twelfth distance is preferably “a distance that does not apply excessive stress to the residual deformable thin object”.

  That is, in this residual deformable thin object gripping device, the edge of the residual deformable thin object is deformed into a chevron by a series of operations of the programmed residual deformable thin object gripping mechanism, and the chevron is gripped by a pair of finger parts. Will be. For this reason, in this residual deformable thin object gripping device, there is no need to use a pair of oppositely oriented hollow needles, adhesive tape, or negative pressure to grip the residual deformable thin object. There is no need to pluck or entangle the thin material so that it has a crease. Therefore, in this residual deformable thin object gripping device, when the residual deformable thin object exists flat on the floor surface or the bottom surface of the container, the residual deformable thin object is damaged or the residual deformable thin object The residual deformable thin object can be automatically gripped with high probability without making a crease in the deformable thin object. The residual deformable thin object gripping device can be constructed from one robot arm (residual deformable thin object gripping mechanism moving mechanism) and one robot hand (residual deformable thin object gripping mechanism). Therefore, this residual deformable thin object gripping device can be manufactured while keeping the manufacturing cost as low as possible.

  The residual deformable thin object gripping device according to the second invention is the residual deformable thin object gripping device according to the first invention, and the control unit further performs the eighth control. In the eighth control, the control unit controls the second approach / separation mechanism so that the hand unit is separated by a distance longer than the second distance (hereinafter referred to as “fourth distance”) after the third control and before the fourth control. . In this case, the third distance in the residual deformable thin object gripping device according to the first invention is replaced with the fourth distance.

  For this reason, in this residual deformable thin object gripping device, the mountain-shaped portion of the residual deformable thin object can be stabilized by appropriately setting the second distance and the fourth distance.

  A residual deformable thin object gripping apparatus according to a third aspect of the present invention is the residual deformable thin object gripping apparatus according to the first or second aspect of the present invention, further comprising an imaging device. The imaging device images the residual deformable thin object and generates image data of the residual deformable thin object. For example, a digital stereo camera is preferable as the imaging device. In the present invention, it goes without saying that the imaging region of the imaging apparatus is limited to the movable region of the residual deformable thin object gripping mechanism. The control device further includes an image analysis unit and a first position determination unit. The image analysis unit analyzes the image data. The first position determination unit determines the first position based on the image analysis result of the image analysis unit.

  For this reason, in this residual deformable thin object gripping device, the residual deformable thin object can be placed in a random manner within the imaging range of the imaging device. Therefore, the residual deformable thin object gripping device greatly contributes to the full automation of the residual deformable thin object handling.

  A residual deformable thin object gripping apparatus according to a fourth invention is the residual deformable thin object gripping apparatus according to the third invention, wherein the image analysis unit binarizes the image data to obtain the contour information of the residual deformable thin object. After deriving, a straight contour portion having a length equal to or longer than the first length (hereinafter referred to as “specific straight contour portion”) is detected from the contour information. The first position determination unit determines the first specified position of the specific straight line contour portion as the first position when only one specific straight line contour portion is detected in the image analysis unit, and the image analysis unit determines the specific straight line contour. When two or more portions are detected, one specific straight contour portion is selected from the specific straight contour portion based on a predetermined condition (hereinafter, the specific straight contour portion thus selected is referred to as “selected specific straight contour portion”. The first specified position of the selected specific straight line contour portion is determined as the first position. The “predetermined condition” here is determined from, for example, the positional relationship between the specific straight contour portion and the residual deformable thin object gripping mechanism.

  For this reason, with this residual deformable thin object gripping apparatus, it is possible to grip a residual deformable thin object having a sufficiently long straight portion with a fairly high probability.

  A residual deformable thin object gripping device according to a fifth aspect of the present invention is the residual deformable thin object gripping device of the fourth aspect of the present invention, in which the first position determining unit is not detected by the image analysis unit as to the specific straight contour portion information. The second prescribed position of the straight contour portion having a length less than the first length is determined as the first position. The control unit performs first control, second control, third control, fourth control, fifth control, sixth control, seventh control, ninth control, and tenth control. In the ninth control, the control unit controls the residual deformable thin object gripping mechanism moving mechanism so as to move the residual deformable thin object gripping mechanism to a position above the third position after the seventh control. In the tenth control, after the ninth control, the control unit controls the first approach / separation mechanism so that the finger unit is separated by a distance longer than the twelfth distance (hereinafter referred to as “the thirteenth distance”). The thirteenth distance must be “a distance at which the finger portion can no longer grip the residual deformable thin object”.

  That is, this residual deformable thin object gripping apparatus repeats the operation of gripping the residual deformable thin object, lifting it up, and releasing it until the specific straight contour portion is detected. For this reason, if this residual deformable thin object gripping apparatus is used, the installer who places the residual deformable thin object does not need to replace the residual deformable thin object every time an error occurs. Therefore, the residual deformable thin object gripping device greatly contributes to the full automation of the residual deformable thin object handling.

  A residual deformable thin object gripping apparatus according to a sixth aspect of the present invention is the residual deformable thin object gripping apparatus according to any of the first to fifth aspects of the present invention, wherein the control unit further performs an eleventh control. In the eleventh control, after the seventh control, the control unit controls the second approach / separation mechanism so that the hand unit is separated by a distance longer than the third distance. In the eleventh control, it is preferable that the control unit moves the hand unit so as to be positioned at both ends of the remaining deformable thin object. In addition, in order to position the hand part at both ends of the residual deformable thin object as described above, a method using the length information from the image data, a side surface of the finger part, and the like are provided with a light emitting element and a light receiving element. A method of attaching a sensor such as an optical sensor is conceivable. When the eleventh control is performed, the residual deformable thin object gripping mechanism may be configured such that the first direction is parallel to a horizontal plane (a plane orthogonal to the vertical direction), or the first direction is a horizontal plane. You may be in the state of crossing.

  For this reason, this residual deformable thin object gripping device not only grips the residual deformable thin object, but also slides the hand part along the edge of the residual deformable thin object while the finger part holds the residual deformable thin object. The residual deformable thin material can be developed (hereinafter, such a development method is referred to as “knob sliding development”). Therefore, the residual deformable thin object gripping device greatly contributes to the full automation of the residual deformable thin object handling.

  In the case where the pinch slide deployment is performed with the residual deformable thin object gripping mechanism so that the first direction is parallel to the horizontal plane, there is a thick part such as a fold on the edge of the residual deformable thin object. preferable. This is because the residual deformable thin object may slide off from the finger part during the sliding movement of the knob. On the other hand, in the case where the pinch slide deployment is performed with the residual deformable thin object gripping mechanism so that the first direction intersects the horizontal plane, the edge of the residual deformable thin object does not have a thick part such as a fold. No problem at all.

  A residual deformable thin object gripping apparatus according to a seventh aspect of the present invention is the residual deformable thin object gripping apparatus according to the sixth aspect of the present invention, wherein the control unit further performs a twelfth control and a thirteenth control. In the twelfth control, after the eleventh control or during the eleventh control, the control unit moves the residual deformable thin object gripping mechanism downward and forward with the first direction parallel to the horizontal plane. The residual deformable thin object gripping mechanism moving mechanism is controlled to move downward and rearward. In the thirteenth control, after the twelfth control, the control unit controls the first approach / separation mechanism so that the finger unit is separated by a distance longer than the twelfth distance (hereinafter referred to as “fourteenth distance”). The 14th distance must be “a distance at which the finger portion can no longer grip the residual deformable thin object”.

  For this reason, this residual deformable thin object gripping device can stand the residual deformable thin object after pinching and sliding the residual deformable thin object. Therefore, the residual deformable thin object gripping device greatly contributes to the full automation of the residual deformable thin object handling.

  A residual deformable thin object gripping apparatus according to an eighth aspect of the present invention is the residual deformable thin object gripping apparatus according to any of the first to seventh aspects of the present invention, wherein the finger portion has a high height at a contact point with the residual deformable thin object. A friction sheet is affixed. The “high friction sheet” referred to here is, for example, a rubber sheet.

  For this reason, this residual deformable thin object gripping device can deform the residual deformable thin object into a mountain shape without increasing the pressing force.

  A residual deformable thin object gripping apparatus according to a ninth aspect of the present invention is the residual deformable thin object gripping apparatus according to any of the first to eighth aspects of the present invention, further comprising a residual deformable thin object gripping mechanism rotating mechanism. The residual deformable thin object gripping mechanism rotating mechanism can rotate the residual deformable thin object gripping mechanism along a plane including the opposing direction and the first direction.

  For this reason, this residual deformable thin object gripping apparatus can grip the residual deformable thin object even if the residual deformable thin object is placed inclined with respect to the horizontal direction.

  A residual deformable thin object gripping device according to a tenth invention is the residual deformable thin object gripping device according to any of the first to ninth inventions, wherein the residual deformable thin object gripping mechanism moving mechanism is a residual deformable thin object gripping device. It is possible to move the mechanism in the up-down direction, the front-rear direction, and the left-right direction.

  For this reason, in this residual deformable thin object gripping device, the degree of freedom of the place where the residual deformable thin object is placed can be increased.

  A residual deformable thin object gripping apparatus according to an eleventh aspect of the invention is the residual deformable thin object gripping apparatus according to any of the first to ninth aspects of the invention, further comprising a residual deformable thin object gripping mechanism turning mechanism. The residual deformable thin object gripping mechanism turning mechanism can turn the residual deformable thin object gripping mechanism.

  For this reason, in this residual deformable thin object gripping device, the degree of freedom of the place where the residual deformable thin object is placed can be increased.

  A residual deformable thin object gripping apparatus according to a twelfth aspect of the present invention is the residual deformable thin object gripping apparatus according to the sixth aspect of the present invention, wherein the pair of finger portions each have a substrate, a first protrusion, and a second protrusion. The first protrusion extends from the base end of the substrate to the first side in the thickness direction of the substrate. The second protrusion extends from the tip of the substrate to the first side in the thickness direction of the substrate. In addition, the second protrusion has a chamfered corner on the side facing the first protrusion. The chamfered surface of the second protrusion may be a flat surface or a curved surface. The pair of finger portions are arranged such that the first protrusions and the second protrusions oppose each other.

  For this reason, even if there is a thick portion such as a folded edge at the edge of the residual deformable thin object, the residual deformable thin object gripping device can smoothly pinch and unfold.

  A residual deformable thin object gripping device according to a thirteenth aspect of the present invention is the residual deformable thin object gripping device of the twelfth aspect of the present invention, wherein the second protrusion is first from the front end portion of the substrate to the first thickness direction side of the substrate. It extends to a height lower than the protrusion. That is, when the first protrusions come into contact with each other in the pair of finger portions, a certain gap is generated between the second protrusions.

  For this reason, this residual deformable thin object gripping device can weaken the gripping force with respect to the residual deformable thin object having a certain range of thickness. Therefore, this residual deformable thin object gripping device does not need to apply excessive stress to the residual deformable thin object having a certain range of thickness. Therefore, this residual deformable thin object gripping device does not unnecessarily damage the residual deformable thin object having a certain range of thickness.

  A residual deformable thin object gripping device according to a fourteenth aspect of the present invention is the residual deformable thin object gripping device according to any of the first to thirteenth aspects of the present invention, and a pressure sensor is attached to the opposing surface of the finger portion. . Moreover, a control part controls the approach distance between finger parts based on the output value of a pressure sensor.

  For this reason, this residual deformable thin object gripping device can make the gripping force of the residual deformable thin object constant regardless of the thickness of the residual deformable thin object. Therefore, this residual deformable thin object gripping device does not apply extra stress to the residual deformable thin object. Therefore, this residual deformable thin object gripping device does not unnecessarily damage the residual deformable thin object.

  In the residual deformable thin object gripping device according to the first aspect of the present invention, when the residual deformable thin object exists flat on the floor surface or the bottom surface of the container, the residual deformable thin object is damaged or the residual deformable thin object is soiled. The residual deformable thin object can be automatically gripped with high probability without making a crease in the residual deformable thin object. The residual deformable thin object gripping device can be constructed from one robot arm (residual deformable thin object gripping mechanism moving mechanism) and one robot hand (residual deformable thin object gripping mechanism). Therefore, this residual deformable thin object gripping device can be manufactured while keeping the manufacturing cost as low as possible.

  In the residual deformable thin object gripping device according to the second aspect of the present invention, the mountain portion of the residual deformable thin object can be stabilized by appropriately setting the second distance and the fourth distance.

  In the residual deformable thin object gripping device according to the third invention, the residual deformable thin object can be placed in a random manner within the imaging range of the imaging device. Therefore, the residual deformable thin object gripping device greatly contributes to the full automation of the residual deformable thin object handling.

  In the residual deformable thin object gripping device according to the fourth aspect of the present invention, the residual deformable thin object having a sufficiently long straight portion can be gripped with a fairly high probability.

  The residual deformable thin object gripping device according to the fifth invention greatly contributes to the full automation of the handling of the residual deformable thin object.

  The residual deformable thin object gripping device according to the sixth aspect of the present invention not only grips the residual deformable thin object but also slides the hand part along the edge of the residual deformable thin object while the finger part holds the residual deformable thin object. Thus, the residual deformable thin material can be developed. Therefore, the residual deformable thin object gripping device greatly contributes to the full automation of the residual deformable thin object handling.

  In the residual deformable thin object gripping device according to the seventh aspect of the present invention, the residual deformable thin object can be allowed to stand after the residual deformable thin object is picked and unfolded. Therefore, the residual deformable thin object gripping device greatly contributes to the full automation of the residual deformable thin object handling.

  The residual deformable thin object gripping device according to the eighth aspect of the invention can deform the residual deformable thin object into a mountain shape without increasing the pressing force.

  The residual deformable thin object gripping device according to the ninth aspect of the present invention can grip the residual deformable thin object even if the residual deformable thin object is placed inclined with respect to the horizontal direction.

  In the residual deformable thin object gripping apparatus according to the tenth aspect of the invention, the degree of freedom of the place where the residual deformable thin object is placed can be increased.

  In the residual deformable thin object gripping apparatus according to the eleventh aspect of the invention, the degree of freedom of the place where the residual deformable thin object is placed can be increased.

  The residual deformable thin object gripping apparatus according to the twelfth aspect of the present invention can smoothly pinch and unfold even if there is a thick part such as a folded edge at the edge of the residual deformable thin object.

  The residual deformable thin object gripping device according to the thirteenth aspect of the invention can weaken the gripping force with respect to the residual deformable thin object having a certain range of thickness. Therefore, this residual deformable thin object gripping device does not need to apply excessive stress to the residual deformable thin object having a certain range of thickness. Therefore, this residual deformable thin object gripping device does not unnecessarily damage the residual deformable thin object having a certain range of thickness.

  The residual deformable thin object gripping device according to the fourteenth aspect of the present invention can make the gripping force of the residual deformable thin object constant regardless of the thickness of the residual deformable thin object. Therefore, this residual deformable thin object gripping device does not apply extra stress to the residual deformable thin object. Therefore, this residual deformable thin object gripping device does not unnecessarily damage the residual deformable thin object.

  As shown in FIG. 1, the fabric processing apparatus 1 according to the embodiment of the present invention grasps a fabric placed on the first placement table 5A, then unfolds the grasped fabric and statically places it on the second placement table 5B. This apparatus is mainly composed of a fabric processing robot 2, a digital stereo camera 3, and a computer 4. In the present embodiment, the digital stereo camera 3 is connected to the computer 4 via a USB cable (not shown), and the fabric processing robot 2 is also connected to the computer 4 via an RS-232C cable (not shown). Connected.

  Hereinafter, the fabric processing robot 2, the digital stereo camera 3, and the computer 4 will be described in detail.

<Cloth processing robot>
As shown in FIGS. 1 to 4, the fabric processing robot 2 mainly includes a robot hand 2 </ b> A and a robot arm 2 </ b> B. As shown in FIGS. 1 and 2, the robot hand 2A is rotatably attached to the tip side portion of the robot arm 2B. Hereinafter, the robot hand 2A and the robot arm 2B will be described in detail.

(1) Robot Hand 2 A of robot hands are mainly comprised from the hand mechanism 21 and the 1st slide mechanism 22, as FIG.

  As shown in FIGS. 5 to 8, the hand mechanism 21 mainly includes a pair of finger portions 21 </ b> A and a second slide mechanism 21 </ b> B.

  As shown in FIGS. 5 to 12, the finger portion 21 </ b> A is classified into an upper finger portion 21 a and a lower finger portion 21 b.

  As shown in FIGS. 9 to 12, the upper finger portion 21 a is mainly formed from a base portion 211, a distal end protruding portion 212, and a proximal end protruding portion 213. The base portion 211 is a block body portion that has a substantially rectangular parallelepiped shape (or thick plate shape). 9-12, the front-end | tip protrusion part 212 is extended toward the thickness direction one side of the base part 211 from the longitudinal direction front end side part of the base part 211. As shown in FIG. Note that, as is apparent from FIGS. 9 to 12, the end protrusion 212 has a flat end surface in the protrusion direction. Further, as is apparent from FIG. 11, the distal protrusion 212 has a semi-cylindrical curved surface facing the proximal protrusion 213. The proximal end protrusion 213 extends from the longitudinal direction proximal end portion of the base portion 211 in the same direction as the protrusion direction of the distal end protrusion 212. In addition, as is apparent from FIGS. 9 to 12, the base end protrusion 213 has a flat end surface in the protrusion direction.

  As shown in FIGS. 9 to 12, the lower finger portion 21 b is mainly formed from a base portion 211, a distal end protruding portion 212, a proximal end protruding portion 213, and a fastening portion 214. The base part 211 is a block body part having a substantially rectangular parallelepiped shape. A rubber sheet is affixed to the bottom surface of the base portion 211 (the surface in contact with the fabric CL). 9-12, the front-end | tip protrusion part 212 is extended toward the thickness direction one side of the base part 211 from the longitudinal direction front end side part of the base part 211. As shown in FIG. Note that, as is apparent from FIGS. 9 to 12, the end protrusion 212 has a flat end surface in the protrusion direction. Further, as is apparent from FIG. 11, the distal protrusion 212 has a semi-cylindrical curved surface facing the proximal protrusion 213. The proximal end protrusion 213 extends from the longitudinal direction proximal end portion of the base portion 211 in the same direction as the protrusion direction of the distal end protrusion 212. In addition, as is apparent from FIGS. 9 to 12, the base end protrusion 213 has a flat end surface in the protrusion direction. The fastening portion 214 is a substantially rectangular parallelepiped (or thick plate-like) block body portion extending in the longitudinal direction from the base end surface of the base portion 211.

  As shown in FIGS. 5 to 12, the upper finger portion 21 a and the lower finger portion 21 b are formed so that end surfaces in the protruding direction of the base end protruding portion 213 and end surfaces in the protruding direction of the distal end protruding portion 212 are mutually connected. Arranged to oppose. In the upper finger portion 21a and the lower finger portion 21b, the height of the proximal projection 213 (length in the projection direction) is 0.2 mm higher than the height of the distal projection 212 (length in the projection direction). Designed to be Therefore, when the end surface in the protrusion direction of the base end protrusion portion 213 of the upper finger portion 21a and the end surface in the protrusion direction of the base end protrusion portion 213 of the lower finger portion 21b are in surface contact, the front end protrusion portion of the upper finger portion 21a. A gap of 0.4 mm is generated between the end surface in the protruding direction of 212 and the end surface in the protruding direction of the tip protruding portion 212 of the lower finger portion 21b. The upper finger portion 21a is fastened to a slider 21e (described later) of the second slide mechanism 21B so as to be slidable. The lower finger portion 21b is provided below the hand mechanism 21 via a fastening portion 214. And is fixedly fastened. That is, the upper finger portion 21a and the lower finger portion 21b can be separated or approached (including contact) by the computer 4 controlling the second slide mechanism 21B.

  As shown in FIG. 5, the second slide mechanism 21B mainly includes a ball screw 21c, a small electric motor 21d, a slider 21e, a coupling 21f, and an LM guide material (not shown). In the second slide mechanism 21B, when the small electric motor 21d starts to rotate, the rotational power is transmitted to the ball screw 21c, and as a result, the ball screw 21c rotates about its own axis. Then, the slider 21e slides linearly along the LM guide material by the rotational power of the ball screw 21c, and as a result, the upper finger portion 21a connected to the slider 21e slides. When the small electric motor 21d is driven in reverse, the traveling direction of the slider 21e is opposite to the moving direction of the slider 21e when the small electric motor 21d is driven forward. The small electric motor 21d is connected to the computer 4 via an RS-232C cable, and rotates forward, reverses, or stops according to a control signal transmitted from the computer 4.

  As shown in FIGS. 5 to 8, the first slide mechanism 22 slides one hand mechanism 21 in the left-right direction, and the other hand mechanism 21 similarly slides in the left-right direction. And a twelfth slide mechanism 22B. The eleventh slide mechanism 22A and the twelfth slide mechanism 22B are mechanically completely independent. The eleventh slide mechanism 22A and the twelfth slide mechanism 22B are mainly composed of a ball screw (not shown), a small electric motor 22d, a slider (not shown), and an LM guide, as shown in FIGS. It is comprised from the material (not shown). In the first slide mechanism 22, when the small electric motor 22d begins to rotate, the rotational power is transmitted to the ball screw, and as a result, the ball screw rotates about its own axis. Then, the slider slides linearly along the LM guide material by the rotational power of the ball screw, and as a result, the hand mechanism 21 connected to the slider slides. When the small electric motor 22d is driven in reverse, the moving direction of the slider is opposite to the moving direction of the slider when the small electric motor 22d is driven forward. That is, the two hand mechanisms 21 can be separated or approached (including contact) by controlling the first slide mechanism 22 by the computer 4. The small electric motor 22d is connected to the computer 4 via an RS-232C cable, and rotates forward, reverses, and stops according to a control signal transmitted from the computer 4.

(2) Robot Arm As shown in FIGS. 1 to 4, the robot arm 2B mainly includes a pedestal 25a, a rotary table 25b, a first connecting portion 25c, a first arm portion 25d, a second connecting portion 25e, and a second. It is comprised from the arm part 25f.

  The pedestal 25a is provided with a turntable 25b on the top plate. The pedestal 25a accommodates a rotation mechanism (not shown) that rotates the rotary table 25b.

  The first connecting portion 25c is fixedly fastened to the rotary table 25b. And the 1st arm part 25d is connected with this 1st connection part 25c.

  The first arm portion 25d is a substantially columnar member, and a proximal end portion is connected to the first connecting portion 25c, and a distal end side portion is connected to the second connecting portion 25e. And this 1st arm part 25d rotates in the surface (henceforth a "1st surface") orthogonal to the surface containing the rotation direction of the turntable 25b centering | focusing on the connection point with the 1st connection part 25c. Can do.

  The second connecting part 25e is connected to the first arm part 25d and the second arm part 25f. And this 2nd connection part 25e can rotate in the 1st surface centering | focusing on the connection point with the 1st arm part 25d.

  The second arm portion 25f is a substantially columnar member, and has a proximal end portion connected to the second connecting portion 25e and a distal end portion connected to the robot hand 2A. The second arm portion 25f can rotate about its own axis. Further, as described above, the tip side portion of the second arm portion 25f is connected to the robot hand 2A so that the robot hand 2A can rotate in the first plane around the connection point.

  Such a robot arm 2B is commercially available and can be easily obtained by those skilled in the art.

<Digital stereo camera>
The digital stereo camera 3 has two imaging units, and each imaging unit can generate digitized grayscale images, color images, and edge images before and after distortion correction by modules attached to the camera. it can. The digital stereo camera 3 transmits these images to the computer 4 via the USB cable every time an image is generated.

  In the present embodiment, the digital stereo camera 3 is focused on the top plate of the first mounting table 5A. The digital stereo camera 3 is fixedly installed so that the top plate of the first mounting table 5A is entirely included in the shooting range.

  In addition, as such a digital stereo camera 3, for example, a Bumbee 2 manufactured by Digicrops can be used.

<Computer>
As shown in FIG. 1, the computer 4 mainly includes a main body, a display, a keyboard, and a mouse.

  The main body includes a motherboard, a CPU, a main memory, a hard disk, a USB interface board, an RS-232C interface board, and the like. Software such as distance determination software, camera calibration software, and cloth processing robot control software is installed in the hard disk, and these software are executed by the CPU, main memory, and the like. The cloth processing robot control software includes a cloth position detection routine and a cloth processing robot operation control routine.

  When the digital stereo camera 3 simultaneously generates images in the two imaging units, the computer 4 collects data of these images from the digital stereo camera 3 by the distance determination software. Next, in the computer 4, the correspondence relationship between the pixels of both images is converted into data by the distance determination software. Subsequently, in the computer 4, the distance to the two-dimensional image coordinate point in the image is obtained based on the stereo camera function and the pixel correspondence data. Thereafter, in the camera module, the most similar object in both images is associated while moving horizontally between the pixels. When the search is completed for all the pixels, the distance to the object in the image is obtained.

  In addition, since such a method is a method well-known to those skilled in the art, it does not carry out detailed description any more.

  In the computer 4, camera coordinates are converted into robot coordinates by camera calibration software. In the present embodiment, camera calibration means a process for obtaining internal variables (such as focal length) and external variables (such as camera posture) of the camera.

  In the present embodiment, this camera calibration is performed as follows.

  First, the marker is moved to a position where the robot coordinates are known in advance. Next, the periphery of the marker is photographed by the digital stereo camera 3. Subsequently, a marker is extracted from an image around the marker by an estimated circle method. The estimated circle method will be described in detail below.

  In the estimation circle method, first, an HSV (color space composed of three components of hue, saturation, and brightness) color system is used for an image, and a color similar to a marker (white) designated in advance and other colors are selected. To binarize. In the present embodiment, the color similar to the marker is white and the other colors are black. Next, a circle with a radius r is drawn for an arbitrary pixel at the two-dimensional image coordinates C (u, v) from the binarized image. Subsequently, the pixel values p of all the pixels included inside the circle are scanned, and when the pixel value p is white, +1 is added, and when the pixel value p is black, -0.5 is added (the following expression) (See (2)). When the total number of pixels included inside the circle is M, the result value F is expressed by the following equation (2). Then, the circle center coordinate when the result value F is maximum is obtained, and the circle center coordinate is set as the marker position in the image, that is, the specified robot coordinate.

  Then, a set (x, w) of the robot coordinate x and the camera coordinate w is measured N times, and coordinate conversion between the two coordinates is performed. The coordinate transformation is expressed by a combination of a linear transformation A and a translation vector t. Specifically, the linear transformation A and the translation vector t are obtained, and the estimated robot coordinate x ′ is obtained by substituting the linear transformation A and the translation vector t into the following equation (3).

  In the present embodiment, a method of minimizing the evaluation value D (see the following expression (4)) is used in order to obtain a combination of the deformation transformation A and the translation vector t.

  Then, the absolute error value diff between the actual robot coordinate x and the estimated robot coordinate x ′ obtained by the above equation (3) is obtained from the following equation (5), and x and x when diff exceeds the threshold value After the pair with 'is removed, the combination of the linear transformation A and the translation vector t is obtained again using the above equation (4).

  In addition, since such a method is a method well-known to those skilled in the art, it does not carry out detailed description any more.

  Further, in the computer 4, the cloth CL is controlled by the cloth processing robot control software, and the control signal for realizing a series of operations from the cloth CL gripping process of the cloth processing robot 2 to the stationary process of the cloth CL. Is generated, and the control signal is sequentially transmitted to the fabric processing robot 2. The determination of the grip location of the fabric CL will be described in detail below.

  In the present embodiment, “a part of the edge of the cloth CL that is in contact with the first mounting table 5A is as close as possible to the robot hand 2A and is a straight line having a certain length or more. "Is defined as the grip location. First, in order to determine whether or not the edge of the fabric CL is in contact with the first mounting table 5A, the height data of the fabric CL from the first mounting table 5A is required. This height data can be easily calculated if the three-dimensional position of the first mounting table 5A is obtained in advance. Therefore, in the present embodiment, a marker sheet is installed on the first mounting table 5A, and the three-dimensional position of the first mounting table 5A is obtained from the three-dimensional coordinates of the marker sheet.

  Specifically, background difference processing is performed from the image of the first mounting table 5A on which the marker sheet is installed and the image of the first mounting table 5A on which the marker sheet is not installed. As a result, the binarized image is obtained. Is derived. Next, a parallax image of the marker sheet region is derived from the parallax image and the binary image, and camera coordinates and robot coordinates are obtained from the parallax image. Thereafter, the three-dimensional coordinates (robot coordinates) of each point on the first mounting table 5A are collected, and the plane equation that best matches the point group is obtained. This plane equation is incorporated in the fabric position detection routine in advance.

  In the cloth position detection routine, the contour extraction process, the straight line part extraction process, and the gripping part determination process of the cloth CL are executed. Hereinafter, the contents of each process will be described in detail. In addition, the outline extraction process of the fabric CL will be described with reference to FIGS. The grip location determination process will be described with reference to FIG.

  In the contour extraction process, a difference process is performed from an image of only the first mounting table 5A prepared in advance and an image of the cloth CL placed on the first mounting table 5A (see FIG. 13). As a result, a binarized image is derived. In the present embodiment, the cloth CL is set to be white and the background portion including the first mounting table 5A is set to be black. In FIG. 14 to FIG. 19, for convenience of explanation, the white pixels are shaded or hatched, and the black pixels are not hatched. Next, it is determined whether the pixel is white or black sequentially from the end pixel (pixel corresponding to the background portion) in the binarized image (see FIG. 14). Then, when it is determined that the pixel next to the pixel determined to be black is white, the white pixel is defined as a first contour pixel (a pixel that is hatched in FIG. 15) ( FIG. 15). Subsequently, while the pixels adjacent to the first contour pixel are scanned counterclockwise, it is determined whether the pixels are white or black (see FIG. 16). Similarly to the above, when it is determined that the pixel next to the pixel determined to be black is white, the white pixel is set as the second contour pixel (see FIG. 17). Thereafter, the n-th contour pixel is detected in the same manner as the detection of the second contour pixel, and this detection is repeated until the first contour pixel is detected again (see FIGS. 18 and 19). As a result, a closed curve, that is, a contour image (see FIG. 20) of the fabric CL is formed.

In the straight line portion extraction process, k-curvature is calculated for each pixel constituting the contour image of the fabric CL. The k-curvature is an amount representing the degree of curve steepness at a certain point on the curve. The larger the value, the steeper the curve is, and the closer this value is to 0. This indicates that the curve is loose, that is, the linearity is good. In the present embodiment, a pixel group whose k-curvature is equal to or less than a predetermined threshold is determined as a straight line portion. When the curve is expressed as a function of y = f (x), the k-curvature k is expressed by the following equation (6). In the present embodiment, k-curvature takes k points to the left and right of the point (x ₀ , y ₀ ) for which k-curvature is to be obtained, and the point (x _−k , y _−k ). To the point (x ₀ , y ₀ ) and the angle θ formed by the vector from the point (x ₀ , y ₀ ) to the point (x _k , y _k ).

  In the gripping part determination process, first, a straight line part whose height from the first mounting table 5A is equal to or less than a predetermined threshold is selected from the straight line parts extracted by the straight line part extraction process. This straight line portion selection process is performed in order to realize that the gripping operation of the robot hand 2A is performed at the portion where the robot cloth CL is in contact with the first mounting table 5A. Further, the height of the straight portion from the first mounting table 5A can be easily obtained from the equation of the plane and the coordinates of the straight portion. Next, a process of connecting the straight line parts selected in the straight line part selection process whose angles with the y-axis of the robot coordinate system are approximate (that is, those whose angle difference is within a predetermined threshold) is connected. Performed (see FIG. 21). In this connection process, in the straight line part extraction process, a part that actually looks straight may not be extracted as one straight line part but may be divided and extracted as two or more straight line parts. Has been done to positively correct. Subsequently, the length of the straight line portion subjected to the connection processing is calculated from the robot coordinates, and a length whose length is equal to or greater than a threshold value is selected. This length regulation selection process is performed based on the idea that it is desirable that the straight line portion held by the robot hand 2A is as long as possible. Finally, a straight line portion having the smallest angle with the robot coordinate system y-axis is selected from the straight line portions selected in the length regulation selection process. This angle regulation selection process is performed due to the fact that the robot hand 2A has a shape extending in the y-axis direction, and that the gripping operation is more easily performed as the angle is smaller.

  Then, the information on the straight line portion selected in the angle defining selection process is written in the main memory, and the information on the end point of the straight line portion is defined as the robot coordinates. If no straight line portion is detected in the grip location determination process, a warning message is displayed on the display. If no straight line portion having a length equal to or greater than the predetermined threshold value is detected in the length regulation selection process, the straight line portion having the maximum length is selected, and the cloth dropping operation described below is performed.

<Operation control of fabric processing device>
As described above, when the straight line portion is selected in the angle regulation selecting process, the computer 4 sequentially transmits control signals to cause the cloth processing robot 2 to perform the cloth processing operation. If no straight line portion having a length equal to or greater than a predetermined threshold is detected in the length regulation selection process, the computer 4 sequentially transmits control signals after the straight line portion having the maximum length is selected. The cloth processing robot 2 is caused to perform a cloth dropping operation. Hereinafter, the cloth processing operation and the cloth dropping operation will be described in detail. In addition, since the person skilled in the art can realize the operation of the following fabric processing operation and fabric dropping operation without undue burden if the operation mode can be understood, what kind of control signal is generated in the computer 4? Is not detailed.

(1) Fabric Processing Operation In the fabric processing operation, first, the robot arm 2B is operated so that the robot hand 2A is positioned at the initial position (see FIG. 22). At this time, in the robot hand 2A, the hand mechanism 21 is operated so that the hand mechanisms 21 are separated from each other by a predetermined distance, and a predetermined gap (cloth CL) is provided between the upper finger portion 21a and the lower finger portion 21b. The upper finger portion 21a is operated so that a gap in which the edge portion of the second finger portion can be inserted is generated.

  Next, the bottom surface of the lower finger portion 21b comes into contact with a predetermined point (for example, a point 6 cm away from an end point on one side and a point further 6 cm away from that point) selected in the angle regulation selection process. Thus, the hand mechanism 21 and the robot arm 2B are operated (see FIG. 23).

  Next, the hand mechanism 21 is moved closer so that the hand mechanism 21 is contracted to a predetermined distance (see FIG. 24). At this time, the portion between the gripped portions of the fabric CL is deformed into a mountain shape.

  Subsequently, the robot arm 2B is operated so that the robot hand 2A is positioned above and behind the previous position (see FIG. 25). At this time, the tip of the finger portion 21A must be behind the edge of the fabric CL in a top view. In order to operate the robot arm 2B in this way, the length in the longitudinal direction of the finger portion 21A is measured in advance and stored in the hard disk of the computer 4 as a control parameter. At this time, the hand mechanisms 21 are operated so that they are closer to each other. This operation is performed in order to insert the two lower finger portions 21b into the lower space of the mountain-shaped portion of the fabric.

  Subsequently, after the robot arm 2B is operated so that the robot hand 2A is positioned below the previous position, the robot arm 2B is operated so that the robot hand 2A is positioned forward from the previous position (FIG. 26). Note that the position in the vertical direction (that is, the height position) of the robot hand 2A at this time is the distance between the hand mechanisms 21 immediately before the cloth CL is deformed into a mountain shape, or the hand mechanism after the cloth CL is deformed into a mountain shape. It can be defined in advance by the distance between the two or the approach distance of the hand mechanism 21 when the fabric CL is deformed into a mountain shape. This is because these distances strongly depend on the height of the mountain-shaped portion of the fabric CL.

  Subsequently, the upper finger portion 21a is moved closer to the lower finger portion 21b until the proximal end projection portion 213 of the upper finger portion 21a and the proximal end projection portion 213 of the lower finger portion 21b come into surface contact. As a result, the finger portion 21A grips the fabric CL (see FIG. 26). At this time, a gap of 0.4 mm is generated between the tip protrusions 212. If the cloth CL has a thickness of 0.4 mm to 0.06 mm, the finger portion 21A does not damage the cloth CL. Can be gripped.

  Subsequently, the robot arm 2B is operated so as to move the robot hand 2A to a position above the second mounting table 5B (see FIG. 27).

  Subsequently, the hand mechanism 21 is operated so that the hand mechanism 21 is separated by a predetermined distance, and the fabric CL is developed (see FIGS. 27 to 29). Note that the separation distance of the hand mechanism 21 at this time is defined in advance by the size of the fabric CL.

  By the way, when there is no thick part such as a fold on the edge of the cloth CL, the cloth CL may fall off the finger portion 21A and fall on the second mounting table 5B during the cloth unfolding operation. For this reason, this operation | movement will be performed suitably for the fabric CL in which thick edge parts, such as folding, exist.

  Then, while the robot hand 2A moves forward, the robot arm 2B is operated so as to approach the second mounting table 5B, and the fabric CL is left standing in a state of being developed on the second mounting table 5B (FIGS. 30 to 33). reference). When the robot hand 2A reaches the specified position, the upper finger portion 21a is raised, and the fabric CL is released from the finger portion 21A.

(2) Cloth drop operation In the fabric drop operation, the same operation as the fabric processing operation is performed until the cloth CL is gripped by the finger portion 21A. When the fabric CL is gripped by the finger portion 21A, the robot arm 2B is operated so as to pull the robot hand 2A upward, and then the upper finger portion 21a is raised, and the fabric CL is released from the finger portion 21A. The That is, the fabric CL is dropped from above toward the first mounting table 5A. Thereafter, the fabric position detection routine is executed again.

<Features of fabric processing device>
(1)
In the fabric processing apparatus 1 according to the embodiment of the present invention, the edge of the fabric CL is deformed into a chevron by a series of operations of the fabric processing robot 2, and the chevron is gripped by the pair of finger portions 21A. For this reason, in this fabric processing apparatus 1, it is not necessary to use a pair of oppositely facing hollow needles, adhesive tape, or negative pressure to grip the fabric CL, and the fabric CL is creased. There is no need to pick and roll as much. Therefore, in the fabric processing apparatus 1, when the fabric CL exists in a flat state on the floor surface, the bottom surface of the container or the like, the fabric CL is not damaged, the fabric CL is not stained, or the fabric CL is not creased. The cloth CL can be automatically gripped with high probability. The fabric processing apparatus 1 is constructed from one robot arm 2B and one robot hand 2A. Therefore, this fabric processing apparatus 1 can be manufactured while keeping the manufacturing cost as low as possible.

(2)
In the fabric processing apparatus 1 according to the embodiment of the present invention, the digital stereo camera 3 is fixedly installed so that the top plate of the first mounting table 5A is included in the photographing range, and the digital stereo camera is provided. The captured image 3 is analyzed by the computer 4 so that the grip position of the fabric CL is derived. For this reason, in this fabric processing apparatus 1, the fabric CL can be placed on the top plate of the first mounting table 5A in a random manner. Therefore, this fabric processing apparatus 1 greatly contributes to the full automation of the handling of the fabric CL.

(3)
In the fabric treatment apparatus 1 according to the embodiment of the present invention, when no straight line portion having a length equal to or greater than the predetermined threshold is detected in the length regulation selection process, the straight line portion having the maximum length is selected. The computer 4 sequentially transmits control signals to cause the cloth processing robot 2 to perform the cloth dropping operation. That is, the fabric processing apparatus 1 repeats the operation of grasping the fabric CL, lifting it up, and releasing it until a straight portion having a length equal to or greater than the threshold is detected. For this reason, if this fabric processing apparatus 1 is used, the supplier of the fabric CL does not need to replace the fabric CL every time an error occurs. Therefore, this fabric processing apparatus 1 greatly contributes to the full automation of the handling of the fabric CL.

(4)
In the fabric processing apparatus 1 according to the embodiment of the present invention, the fabric processing apparatus 1 performs an operation of unfolding and leaving the fabric CL after the fabric CL is gripped by the robot hand 2A. Therefore, this fabric processing apparatus 1 greatly contributes to the full automation of the handling of the fabric CL.

(5)
In the fabric processing apparatus 1 according to the embodiment of the present invention, the surface of the finger portion 21 </ b> A that opposes the proximal projection 213 of the distal projection 212 is a semi-cylindrical curved surface. For this reason, even when there is a thick portion such as a folded edge at the edge of the fabric CL, the fabric processing device 1 can smoothly pinch and unfold.

(6)
In the fabric processing apparatus 1 according to the embodiment of the present invention, the height of the proximal projection 213 (the length in the projection direction) is the height of the distal projection 212 (projection) in the upper finger portion 21a and the lower finger portion 21b. It is designed to be 0.2 mm higher than the length in the direction). Therefore, when the end surface of the upper finger portion 21a in the protrusion direction of the base end protrusion portion 213 and the end surface of the lower finger portion 21b in the protrusion direction of the base end protrusion portion 213 are in surface contact, the distal end protrusion of the upper finger portion 21a. A gap of 0.4 mm is generated between the end surface in the protruding direction of the portion 212 and the end surface in the protruding direction of the tip protruding portion 212 of the lower finger portion 21b. For this reason, this fabric processing apparatus 1 can weaken the gripping force with respect to the fabric CL having a certain range of thickness. Therefore, this fabric processing apparatus 1 does not need to apply excessive stress to the fabric CL having a certain range of thickness. Therefore, this fabric processing apparatus 1 does not damage the fabric CL having a certain range of thickness.

(7)
In the fabric processing apparatus 1 according to the embodiment of the present invention, a rubber sheet is affixed to the bottom surface (the surface in contact with the fabric CL) of the base portion 211 of the lower finger portion 21b. For this reason, this fabric processing apparatus 1 can deform the fabric CL into a mountain shape without increasing the pressing force.

<Modification>
(A)
Although the digital stereo camera 3 is employed in the fabric processing apparatus 1 according to the previous embodiment, a digital monocular camera may be employed. In such a case, it takes time and effort to measure the distance from the camera manually in advance.

(B)
In the fabric processing apparatus 1 according to the previous embodiment, the computer 4 is employed as the control device, but a microcomputer may be employed as the control device.

(C)
In the fabric processing apparatus 1 according to the previous embodiment, the grip location of the fabric CL is specified using the digital stereo camera 3, but the digital stereo camera 3 is removed and the fabric installation position and its installation state in advance. You may prescribe. In such a case, it is preferable to attach a marker so that the installation position is clear and attach an instruction note or the like indicating the installation state in the vicinity of the installation position.

(D)
In the fabric processing apparatus 1 according to the previous embodiment, the fabric CL is the processing target. However, a film, paper, or other sheet-like material may be the processing target.

(E)
In the fabric processing apparatus 1 according to the previous embodiment, the ball screw mechanism is adopted as the first slide mechanism 22 and the second slide mechanism 21B, but an air cylinder mechanism and a motor cylinder are used as the first slide mechanism 22 and the second slide mechanism 21B. A mechanism such as a mechanism, an electric slider mechanism, a belt slider mechanism, a linear slider mechanism, or a rack and pinion mechanism may be employed.

(F)
In the fabric processing apparatus 1 according to the previous embodiment, the robot arm 2B as shown in FIG. 1 is employed. However, a rail-type robot arm that moves back and forth, right and left, and up and down may be employed.

(G)
In the fabric processing apparatus 1 according to the previous embodiment, the lower finger portion 21b is fixed and the upper finger portion 21a is slidable. However, both the upper finger portion 21a and the lower finger portion 21b are slidable. It may be configured as described above.

(H)
In the fabric processing apparatus 1 according to the previous embodiment, the clearance between the end surface in the protrusion direction of the tip protrusion 212 of the upper finger portion 21a and the end surface in the protrusion direction of the tip protrusion 212 of the lower finger portion 21b is 0.4 mm. However, the gap is not particularly limited, and may be appropriately changed depending on the thickness of the cloth CL to be processed. In such a case, the finger portion 21A may be removable, and the finger portion 21A may be appropriately selected and attached depending on the thickness of the fabric CL.

(I)
In the fabric processing apparatus 1 according to the previous embodiment, the digital stereo camera 3 is connected to the computer 4 via the USB cable. However, the digital stereo camera 3 may be connected to the computer 4 via another communication cable. Alternatively, the computer 4 may be wirelessly connected.

(J)
In the fabric processing apparatus 1 according to the previous embodiment, the fabric processing robot 2 is connected to the computer 4 via the RS-232C cable. However, the fabric processing robot 2 may be connected to the computer 4 via another communication cable. Alternatively, the computer 4 may be wirelessly connected.

(K)
In the fabric processing apparatus 1 according to the previous embodiment, camera calibration is performed by marker extraction by the estimation circle method. However, as a camera calibration method, other known methods (for example, JP-A-11-37721, JP-A-2005-186193, JP-A-2006-145419, JP-A-10-221066) may be used.

(L)
In the fabric processing apparatus 1 according to the previous embodiment, the straight portion having a length equal to or greater than the threshold is determined as the grip location by the fabric grip position determination routine, but the corner portion of the fabric CL is determined as the grip location. Good. In such a case, the Robotics Society of Japan Vol. 15 No. 2, pp. It can be realized by using the technique described in 275-283, 1997.

(M)
Although not particularly mentioned in the previous embodiment, a pressure sensor may be attached to the tip protrusion 212 of the finger portion 21A to grip the fabric CL with a specified pressure. In this way, regardless of the thickness of the cloth CL, the gripping force of the finger portion 21A with respect to the cloth CL can be kept constant, and it is not necessary to apply extra stress to the cloth CL.

(N)
In the fabric processing apparatus 1 according to the previous embodiment, the robot hand 2A is moved downward while being advanced by the robot arm 2B during the stationary operation of the fabric. However, as shown in FIG. The robot arm 2B may be moved forward while being moved backward after being moved forward by the robot arm 2B.

(O)
In the fabric processing apparatus 1 according to the previous embodiment, when the robot hand 2A is positioned at the initial position, the upper finger portion 21a operates such that a predetermined gap is generated between the upper finger portion 21a and the lower finger portion 21b. I was allowed to. However, the upper finger portion 21a may be in contact with the lower finger portion 21b at the initial position. In this case, the upper finger portion 21a is raised before the cloth CL is gripped, and a predetermined gap (a gap through which the edge portion of the cloth CL can be inserted) is formed between the upper finger portion 21a and the lower finger 21b. ) Must be operated so that the upper finger portion 21a is operated.

(P)
In the fabric processing apparatus 1 according to the previous embodiment, after the hand mechanism 21 is approached so that the distance of the hand mechanism 21 is reduced to a specified distance and the fabric CL is deformed into a mountain shape, the robot hand 2A is The robot arm 2B is moved so as to be positioned above and behind the position, but after the hand mechanism 21 is approached so that the distance of the hand mechanism 21 is reduced to a specified distance and the fabric CL is deformed into a mountain shape. The hand mechanism 21 may be slightly separated to stabilize the chevron shape of the fabric CL.

(Q)
In the fabric processing apparatus 1 according to the previous embodiment, the separation distance of the hand mechanism 21 when the hand mechanism 21 is operated and the cloth CL is deployed so that the hand mechanism 21 is separated by a predetermined distance is the size of the cloth CL. For example, when a light emitting element is attached to the outer surface of the upper finger part 21a and a light receiving element is attached to the outer surface of the lower finger part 21b, and the light receiving element receives light from the light emitting element. The sliding movement of the hand mechanism 21 may be stopped when the light emitting element is exposed from the cloth CL. Of course, the light receiving element may be attached to the outer surface of the upper finger portion 21a, and the light receiving element may be attached to the outer surface of the lower finger portion 21b. If it does in this way, the fabric processing apparatus 1 can respond | correspond to the cloth CL of arbitrary magnitude | sizes.

(R)
Although not particularly mentioned in the previous embodiment, the digital stereo camera 3 is set to the continuous shooting mode, and the cloth position detection routine is executed from the time when the white pixel is detected in the binarized image. Good. In such a case, the binarized image derivation process of the contour extraction process can be omitted. In such a case, after the white pixel is detected, it is preferable to stop photographing of the first mounting table 5A by the digital stereo camera 3 until the cloth processing operation or the cloth dropping operation is completed. Further, in such a case, after the fabric processing operation or the fabric dropping operation is completed, the digital stereo camera 3 may be set to resume the shooting of the first mounting table 5A.

(S)
In the fabric processing apparatus 1 according to the previous embodiment, the development process of the fabric CL is performed while the first slide mechanism 22 is kept horizontal. However, as shown in FIG. 35, the first slide mechanism 22 is in the vertical direction. The cloth CL may be unfolded in a state where the cloth CL is directed to the cloth. In this way, the cloth CL can be deployed without any problem even if there is no thick part such as a fold at the edge of the cloth CL. In such a case, the lower hand mechanism 21 is slid downward, the direction of the robot hand 2A is reversed, and the lower hand mechanism 21 is slid downward. Further, the hand mechanism 21 may be moved to one side before the cloth CL is gripped, and the corners of the cloth CL may be gripped by the finger portion 21A. In such a case, it is necessary to introduce the technique shown in the modification (L). In such a case, when the first slide mechanism 22 is oriented in the vertical direction, the robot hand 2A needs to be rotated so that the finger portion 21A comes up.

  The same effect can be obtained even when the first slide mechanism 22 intersects the horizontal plane. In such a case, it is necessary to rotate the robot hand 2A so that the tip of the finger portion 21A faces obliquely upward.

(T)
Although not particularly mentioned in the previous embodiment, a rotation mechanism that rotates the robot hand 2A so that the first slide mechanism 22 rotates in the vertical direction may be incorporated in the robot arm 2B. In this way, the fabric processing apparatus 1 can hold the fabric CL even when the fabric CL is inclined with respect to the horizontal direction.

(U)
In the fabric processing apparatus 1 according to the previous embodiment, the surface of the finger portion 21A that opposes the proximal end protrusion 213 of the distal end protrusion 212 is a semi-cylindrical curved surface, but this surface is an elliptical curved surface. Alternatively, it may be a refracting surface.

(V)
In the fabric processing apparatus 1 according to the previous embodiment, the finger part 21A is configured such that the upper finger part 21a slides, but at least one of the upper finger part 21a and the lower finger part 21b is the finger part. You may comprise so that it may rotate using a base end part as a fulcrum.

(W)
In the fabric processing apparatus 1 according to the previous embodiment, the two hand mechanisms 21 are slidable together, but one hand mechanism may be fixed and the other hand mechanism may be slidable.

  The residual deformable thin object gripping device according to the present invention may damage the residual deformable thin object or damage the residual deformable thin object when the residual deformable thin object such as fabric is present on the floor or the bottom surface of the container. It is possible to automatically grip the residual deformable thin object with high probability without fouling or crease the residual deformable thin object, and to keep the manufacturing cost as low as possible, It is useful as a fabric processing device for the apparel industry, cleaning industry, linen supply industry, welfare industry, medical industry, and the like.

1 is an external perspective view of a fabric processing apparatus according to an embodiment of the present invention. It is a side view of the fabric processing robot which concerns on embodiment of this invention. It is a top view of the fabric processing robot which concerns on embodiment of this invention. It is a rear view of the fabric processing robot which concerns on embodiment of this invention. 1 is an external perspective view of a robot hand according to an embodiment of the present invention. It is a front view of the robot hand concerning an embodiment of the invention. It is a side view of the robot hand concerning an embodiment of the invention. It is a bottom view of the robot hand concerning an embodiment of the invention. It is an external appearance perspective view of the finger part which concerns on embodiment of this invention. It is a side view of the finger part concerning an embodiment of the invention. It is a top view of the lower finger part which concerns on embodiment of this invention. It is a front view of the lower finger part concerning an embodiment of the invention. It is an image of the fabric used as the process target of the fabric processing apparatus which concerns on embodiment of this invention. It is a 1st figure explaining the outline extraction process in the computer which concerns on embodiment of this invention. It is a 2nd figure explaining the contour extraction process in the computer which concerns on embodiment of this invention. It is a 3rd figure explaining the outline extraction process in the computer which concerns on embodiment of this invention. It is a 4th figure explaining the outline extraction process in the computer which concerns on embodiment of this invention. It is a 5th figure explaining the outline extraction process in the computer which concerns on embodiment of this invention. It is the 6th figure explaining the outline extraction processing in the computer concerning an embodiment of the invention. It is the outline image of the fabric obtained as a result of the outline extraction process in the computer which concerns on embodiment of this invention. It is a figure explaining the grip location determination process in the computer which concerns on embodiment of this invention. It is a 1st figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 2nd figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 3rd figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 4th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 5th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 6th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 7th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is an 8th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 9th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 10th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is an 11th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a 12th figure which shows operation | movement of the fabric processing robot which concerns on embodiment of this invention. It is a figure which shows operation | movement of the fabric processing robot which concerns on a modification (N). It is a figure which shows operation | movement of the fabric processing robot which concerns on a modification (S).

Explanation of symbols

1 Fabric processing device (residual deformable thin object gripping device)
2 Fabric processing robot (residual deformable thin object gripping device)
2A Robotic hand (residual deformable thin object gripping mechanism)
2B Robot arm (Residual deformable thin object gripping mechanism moving mechanism, residual deformable thin object gripping mechanism rotating mechanism, residual deformable thin object gripping mechanism turning mechanism)
3 Digital stereo camera (imaging device)
4 Computer (control device)
21 Hand mechanism (hand part)
21A Finger part 21B Second slide mechanism (first approach / separation mechanism)
22 First slide mechanism (second approach / separation mechanism)
211 Base part (substrate)
212 Tip protrusion (second protrusion)
213 Base end protrusion (first protrusion)
CL fabric (residual deformable thin material)

Claims (14)

A residual deformable thin object gripping device for gripping a residual deformable thin object,
A pair of finger portions that oppose each other, and a pair of finger portions that are moved relative to each other along a surface including a facing direction of the pair of finger portions (hereinafter referred to as a “first surface”) to approach the pair of finger portions and And at least two hand portions having a first approaching / separating mechanism that can be separated from each other, and the hand portions on the same straight line along a direction orthogonal to the first surface (hereinafter referred to as “first direction”). A residual deformable thin object gripping mechanism including a second approaching / separating mechanism capable of moving relative to each other to move the hand part closer and away;
A residual deformable thin object gripping mechanism moving mechanism capable of moving the residual deformable thin object gripping mechanism at least in the vertical direction and the front-back direction; and
A first control for controlling the second approach / separation mechanism so that the hand portion is separated by a first distance; and one finger portion is an edge of the residual deformable thin object after the first control or during the first control. A second control for controlling the residual deformable thin object gripping mechanism moving mechanism so as to move the residual deformable thin object gripping mechanism to a position in contact with a portion (hereinafter referred to as a “first position”), and after the second control, A third control for controlling the second approaching / separating mechanism so that the hand portion approaches a distance shorter than the first distance (hereinafter referred to as a “second distance”); and gripping the residual deformable thin object after the third control A fourth control for controlling the residual deformable thin object gripping mechanism moving mechanism so as to move the mechanism to a position above and below the first position (hereinafter referred to as a “second position”); The hand during the fourth control A fifth control for controlling the second approach / separation mechanism so as to approach a distance shorter than the second distance (hereinafter referred to as a “third distance”), and the finger after the fourth control or after the fifth control. The residual deformable thin object gripping mechanism is moved so that the residual deformable thin object gripping mechanism is moved to at least a position ahead of the second position (hereinafter referred to as “third position”) in a state where the portions are separated by an eleventh distance. A sixth control for controlling the mechanism, and a first control for controlling the first approach / separation mechanism so that the finger portion approaches a distance shorter than the eleventh distance (hereinafter referred to as a “twelfth distance”) after the sixth control. 7 A residual deformable thin object gripping device comprising a control device having a control unit for performing control. The control unit controls the second approach / separation mechanism so that the hand unit is separated by a distance longer than the second distance (hereinafter referred to as “fourth distance”) after the third control and before the fourth control. Further performing the eighth control,
The residual deformable thin object gripping device according to claim 1, wherein the third distance is the fourth distance. An imaging device that images the residual deformable thin object and generates image data of the residual deformable thin object;
3. The control device according to claim 1, further comprising: an image analysis unit that performs image analysis on the image data; and a first position determination unit that determines the first position based on an image analysis result of the image analysis unit. The residual deformable thin object gripping device described. The image analysis unit binarizes the image data to derive the contour information of the residual deformable thin object, and then, from the contour information, a linear contour portion having a length equal to or greater than a first length (hereinafter, “specific” Straight outline part ”)
The first position determination unit determines a first specified position of the specific straight line contour part as the first position when only one specific straight line contour part is detected in the image analysis unit, and the image analysis unit When two or more specific straight contour portions are detected, one specific straight contour portion is selected from the specific straight contour portions based on a predetermined condition (hereinafter referred to as the specific straight contour portion thus selected). And the first specified position of the selected specific straight line contour portion is determined as the first position. 4. The residual deformable thin object gripping device according to claim 3, wherein The first position determination unit determines a second specified position of a straight contour portion having a length less than the first length when the specific straight contour portion information is not detected in the image analysis unit. As a position,
The control unit includes the first control, the second control, the third control, the fourth control, the fifth control, the sixth control, the seventh control, and the seventh control. A ninth control for controlling the residual deformable thin object gripping mechanism moving mechanism so that the residual deformable thin object gripping mechanism is moved to a position higher than the third position after the control; and after the ninth control, The residual deformable thin object gripping device according to claim 4, wherein a tenth control is performed to control the first approach / separation mechanism so that the distance is longer than the twelfth distance. 6. The control unit according to claim 1, wherein the control unit further performs an eleventh control for controlling the second approach / separation mechanism so that the hand unit is separated by a distance longer than the third distance after the seventh control. The residual deformable thin object gripping device described. The controller is configured to move the residual deformable thin object gripping mechanism downward and forward while the first direction is parallel to a horizontal plane after the eleventh control or during the eleventh control. A twelfth control for controlling the residual deformable thin object gripping mechanism moving mechanism to move downward and rearward, and the first control for separating the finger portion by a distance longer than the twelfth distance after the twelfth control. The residual deformable thin object gripping device according to claim 6, further performing a thirteenth control for controlling the approaching / separating mechanism. The residual deformable thin object gripping device according to any one of claims 1 to 7, wherein a high friction sheet is attached to the finger portion at a contact point with the residual deformable thin object. The residual deformable thin object gripping mechanism rotating mechanism capable of rotating the residual deformable thin object gripping mechanism along a plane including the opposing direction and the first direction. The residual deformable thin object gripping device described. The residual deformable thin object according to any one of claims 1 to 9, wherein the residual deformable thin object gripping mechanism moving mechanism is capable of moving the residual deformable thin object gripping mechanism in a vertical direction, a front-rear direction, and a left-right direction. Gripping device. The residual deformable thin object gripping device according to any one of claims 1 to 9, further comprising a residual deformable thin object gripping mechanism pivoting mechanism capable of pivoting the residual deformable thin object gripping mechanism. The pair of finger portions includes a substrate, a first projecting portion extending from a base end portion of the substrate to a first thickness direction side of the substrate, and a first projection direction of the substrate from a distal end portion of the substrate. Each of the first protrusions and the second protrusions facing each other, and the first protrusions and the second protrusions are opposed to each other. The residual deformable thin object gripping device according to claim 6. The residual deformable thin object gripping device according to claim 12, wherein the second protrusion extends from the front end of the substrate to the first side in the plate thickness direction of the substrate to a height lower than the first protrusion. . A pressure sensor is attached to the opposing surface of the finger portion,
The residual deformable thin object gripping device according to any one of claims 1 to 13, wherein the control unit controls an approach distance between the finger units based on an output value of the pressure sensor.

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