WO2017171308A1

WO2017171308A1 - Assembly control method and assembly teaching method using passive stiffness gripper

Info

Publication number: WO2017171308A1
Application number: PCT/KR2017/003148
Authority: WO
Inventors: 박동일; 박찬훈; 김휘수; 도현민; 윤동원; 최태용; 경진호; 손영수
Original assignee: 한국기계연구원
Priority date: 2016-04-01
Filing date: 2017-03-23
Publication date: 2017-10-05

Abstract

Disclosed are an assembly control method and an assembly teaching method using a passive stiffness gripper, the assembly control method moving a robot along a previously set path so that a first component gripped by the passive stiffness gripper is moved to a location adjacent to a second component which is the object to be assembled. Displacement data for the passive stiffness gripper is acquired while the first component and second component are assembled. On the basis of data analyzed in the assembly state analysis step, the path of the robot or stiffness of the passive stiffness gripper is modified.

Description

Assembly control method and teaching method using manual rigid gripper

The present invention facilitates the assembly teaching by providing a rigidity that can properly cope with the positional error and processing tolerance of the workpiece during assembly, it is possible to grasp the assembly state during the assembly operation to modify the path of the assembly position assembly speed And an assembly control method and an assembly teaching method using a manual rigid gripper capable of improving assembly quality.

Recently, there is a great interest in the use of robots for the automation of various product production processes. Accordingly, robots are used in various fields such as transportation of assembly parts, welding, and painting.

However, as the assembly work becomes complicated, automation using robots in the assembly line of parts is difficult. In addition, the existing position-based robot has high repeatability, so it is easy to apply to the assembly of work pieces that are always located at the same position, but the positional error and processing tolerance of the work may occur in the conveyor system that occupies most of the assembly line. Poetry is difficult to respond to.

In order to overcome this limitation of position control, studies on various robot assembly based on force control have been conducted. However, force control-based assembly robots require very expensive force sensors, slow work speeds, and are difficult for practical use due to the high possibility of robot divergence depending on the control system. In addition, since the user moves and teaches the entire robot, it is difficult to precisely teach according to the high inertia of the robot. In addition, when excessive contact force between the parts to be assembled, there is a possibility that the parts are broken.

Accordingly, in order to maximize the applicability to the actual manufacturing industry, RCC (Remote Compliance Center) that can be assembled using manual stiffness has been developed and utilized, but there is a limit to the rigidity that can be provided and it is difficult to apply to horizontal assembly. In addition, it is impossible to determine the assembly state, and there is a limitation in application because it is impossible to modify the path according to the measured rigidity.

Related prior art documents include Japanese Patent Laid-Open No. JP 1994-005828 (1994.01.25.).

The present invention has been made to solve the problems described above, the object of the present invention is to grasp the assembly state during the assembly operation can modify the path of the assembly position manual rigid gripper that can improve the assembly speed and assembly quality It is to provide an assembly control method using.

In addition, another object of the present invention is to provide an assembly teaching method using the manual rigid gripper which is easy to teach by assembling to provide rigidity that can appropriately cope with the positional error and processing tolerance of the workpiece during assembly.

Assembly control method using a manual rigid gripper according to an embodiment of the present invention for achieving the above object is input in advance to move the first component gripped by the manual rigid gripper to a position adjacent to the second component to be assembled Move the robot along the path. While assembling the first part and the second part, displacement information of the passive rigid gripper is obtained to determine an assembly state. The rigidity of the path of the robot or the manual rigid gripper is changed based on the information identified in the assembling state checking step.

In an embodiment, the method may further include a reassembly performing step of performing reassembly based on the path of the robot or the rigidity of the manual rigid gripper changed in the assembly strategy modification step.

In one embodiment, the reassembly may be performed several times.

Assembling teaching method using a manual rigid gripper according to an embodiment of the present invention for achieving another object as described above is to move the robot to move the first component gripped by the manual rigid gripper to a position adjacent to the second component to be assembled. Move and store the position information of the passive rigid gripper. As the moved position is not accurate and additional movement is required, as the external force is applied, the position of the passive rigid gripper holding the first part is deformed or further moved to be assembled to the second part.

The position information of the passive rigid gripper in the additional movement step is obtained, and a position error with the position information in the position information storage step is calculated. Based on the position error calculated in the error calculation step, the position information of the passive rigid gripper in the position information storage step is corrected.

In an embodiment, the method may further include a reassembly performing step of assembling the first part to the second part by moving the robot based on the location information modified through the location information correcting step.

In one embodiment, in the further movement step, an additional movement command may be applied to the entire robot by using the displacement of the manual rigid gripper generated by the external force.

In one embodiment, in the further movement step, an external force is applied to the end of the passive rigid gripper that holds the first component to generate a displacement of the substructure of the passive rigid gripper to be assembled to the second component. Can be.

In one embodiment, in the further movement step, the rigidity of the passive rigid gripper holding the first part may be changed to be relatively low.

In one embodiment, the manual rigid gripper is mounted to the arm of the robot, the manual rigid gripper is capable of adjusting the rigidity and the displacement can be measured.

In one embodiment, the passive rigid gripper, the rigidity is formed between the two sides so that the other side is deformable in a fixed state of one side, the manual rigid portion that can adjust the stiffness, is installed in the passive rigid portion, changing the stiffness A variable stiffness device, a displacement measuring means installed in the manual stiffness part, capable of measuring displacement due to deformation of the manual stiffness part, and a gripper mounting part having a gripper part connected to the other side of the manual stiffness part and equipped with a gripper part for holding a part. It may include.

In one embodiment, the variable stiffness device and the gripper controller is further connected to the displacement measuring means, wherein the gripper controller, the stiffness control unit for adjusting the stiffness of the variable stiffness device, the displacement measured in the displacement measuring means A displacement calculation unit for calculating a position of the lower end of the gripper portion based on the, and the stiffness calculation unit connected to the stiffness adjustment unit and the displacement calculation unit.

In one embodiment, the gripper controller, based on the position of the bottom of the gripper portion calculated by the displacement calculation unit, by calculating the stiffness in the stiffness calculator can adjust the stiffness of the variable stiffness device through the stiffness control unit. .

In one embodiment, the gripper controller may provide the robot controller with a target movement path and a target position based on the position of the bottom of the gripper portion calculated by the displacement calculator.

Through the assembly control method and assembly teaching method using the manual rigid gripper according to the present embodiment, it is possible to provide the rigidity that can appropriately cope with the positional error and processing tolerance of the workpiece during assembly, can be applied to a variety of assembly, There is an advantage that can be applied to various assembly, such as vertical direction and horizontal direction.

In addition, it is highly applicable to a variety of robots, there is an advantage that allows the user to teach safe and easy assembly.

In addition, it is possible to modify the path of the assembly position to determine the assembly state during assembly work has the advantage of improving the assembly speed and assembly quality.

1 is a perspective view showing a state in which the passive rigid gripper is mounted on the arm of a robot.

2 and 3 are conceptual views showing a passive rigid gripper used in the assembly control method according to an embodiment of the present invention.

4 and 5 are assembled and exploded perspective views showing the passive rigid gripper of Figure 2;

FIG. 6 is an exploded perspective view of the Stuart platform in the passive rigid gripper of FIG. 2. FIG.

7 and 8 are perspective and front views illustrating a state in which the stewart platform and the balloon are assembled in the manual rigid gripper of FIG. 2.

FIG. 9 is a schematic view showing displacement along a linear stretch of a leg in the Stewart platform of FIG. 6.

10 is a flowchart illustrating an assembly control method using the passive rigid gripper of FIG. 2 according to an embodiment of the present invention.

FIG. 11 is a front view illustrating a state in which centers between the insertion holes of the first and second parts to be assembled do not coincide with each other when the robot is moved to the target position through the position shifting step of FIG. 10.

12 and 13 are front views illustrating a state in which the first part is assembled into the insertion hole of the second part while the manual rigid gripper is deformed through the assembling state determining step of FIG. 10.

14 and 15 show that the robot moves to the corrected target position through the assembly strategy modification step and the reassembly performing step of FIG. 10 in a state where the centers of the insertion holes of the first and second parts to be assembled coincide. The front view which shows the state assembled.

16 and 17 are conceptual views illustrating a passive rigid gripper used in an assembly teaching method according to another embodiment of the present invention.

FIG. 18 is a flowchart illustrating an assembly teaching method using the passive rigid gripper of FIG. 16 according to another embodiment of the present disclosure.

FIG. 19 is a front view illustrating a state in which centers between the insertion holes of the first and second parts to be assembled do not coincide with each other when position information is provided to the robot through the location information storing step of FIG. 18.

20 is a perspective view illustrating a state in which an external force is applied to the entire robot through the additional moving step of FIG. 18.

21 and 22 are front views illustrating a state in which an external force is applied to the lower side of the gripper to insert the first part into the insertion hole of the second part through the additional moving step of FIG. 18.

* Explanation of the sign

1000, 1001, 1002: Manual Rigid Grippers

100, 101, 102: passive rigid portion 110: superstructure

111: settlement home 112: entrance and exit euro

120: lower structure 121: settle groove

122: gripper mounting portion 130: leg

131: ball joint 132: displacement measuring means

140: cover 200: variable rigidity device

300: gripper portion 320: finger

400: gripper controller 410: displacement calculation unit

420: rigidity control unit 430: rigidity calculation unit

2000: robot 2100: arm 2200: robot controller 10: first part

20: second part 21: insertion hole

Hereinafter, an assembly control method using a manual rigid gripper capable of measuring displacement of the present invention as described above will be described in detail with reference to the accompanying drawings.

Referring to FIG. 1, first, in the present embodiment, the passive rigid gripper 1000 may be coupled to an end portion of the arm 2100 of the robot 2000, and assembly control using the manual rigid gripper according to the present exemplary embodiment may be performed. The method and the assembly teaching method using the manual rigid gripper can be used to hold the component to be assembled with the finger 320 to be inserted and inserted into the component to be assembled.

Hereinafter, first, a manual rigid gripper used in the assembly control method using the manual rigid gripper according to the present embodiment will be described in detail with the manual rigid gripper 1000 coupled to the robot 2000.

In the present embodiment, the passive rigid gripper 1000 can adjust the rigidity, and the displacement of the passive rigid gripper 1000 can be measured.

That is, as shown in FIG. 1, the manual rigid gripper 1000 is mounted at the end of the arm 2100 so that the first component 10 can be gripped, and the manual rigid gripper 1000 can adjust the rigidity. It is formed so that the compliance can be changed according to the adjustment of the rigidity. In addition, the passive rigid gripper 1000 may be measured a displacement that changes according to the deformation in the axial direction or the rotation (bending or twisting) about the axis.

More specifically, referring to FIGS. 2 and 3, the passive rigid gripper 1000 forms rigidity between both sides to allow deformation of the other side in a state where one side is fixed, and a manual rigid part that can adjust the formed rigidity. 100 is installed in the passive rigid portion 100, the variable stiffness device 200 for changing the rigidity, is installed in the passive rigid portion 100, it is possible to measure the displacement due to the deformation of the passive rigid portion 100 Displacement measuring means 132, and the gripper mounting portion 122 is formed on the other side of the passive rigid portion 100, the gripper portion 300 for holding the component is mounted.

That is, the manual rigid gripper 1000 has a variable stiffness device 200 that can change the stiffness in the manual stiffness part 100 is installed, the stiffness of the variable stiffness device 200 can be changed through the manual stiffness part 100. According to the rigidity of the variable stiffness device 200 to be changed, the manual stiffness part 100 may be controlled to be easily deformed or difficult to deform. In this case, the passive rigid portion 100 may be configured in various forms that can adjust the rigidity of the variable rigidity device 200.

The variable stiffness device 200 may be interposed between one side and the other side of the passive rigid portion 100, the upper side of the variable stiffness device 200 is coupled to one side of the passive rigid portion 100 and the other side of the manual rigid portion 100 The lower side of the variable rigidity device 200 may be coupled to.

In addition, the variable stiffness device 200 may be formed to have a predetermined stiffness and to change the stiffness. For example, the variable stiffness device 200 may include an elastic body such as a spring and a means for changing the stiffness of the elastic body. . Thus, if the rigidity of the variable stiffness device 200 becomes large, the compliance of the passive rigid gripper becomes small, whereas if the rigidity decreases, the compliance becomes large.

That is, when the positional error or processing tolerance between the parts assembled during assembly is small, even if the stiffness of the variable stiffness device 200 is kept relatively large, smooth assembly is possible, but when the position error or processing tolerance is large By changing the stiffness of the variable stiffness device relatively small, the manual stiffness part 100 can be easily deformed, thereby enabling a smooth assembly.

2 and 3, the manual rigid gripper 100 further includes a gripper controller 400 to which the variable rigidity device 200 and the displacement measuring means 132 are connected.

In this case, the gripper controller 400, the stiffness control unit 420 for adjusting the stiffness of the variable stiffness device 200, the lower end of the gripper unit 300 based on the displacements measured by the displacement measuring means 132 Displacement calculation unit 410 for calculating the position of the stiffness control unit 420 and the stiffness calculation unit 430 connected to the displacement calculation unit 410 is included.

Therefore, the gripper controller 400 calculates the stiffness by the stiffness calculator 430 according to the position of the lower end of the gripper 300 calculated by the displacement calculator 410, and then varies the stiffness controller 420. The rigidity of the stiffness device 200 is adjusted.

More specifically, as shown in FIGS. 2 and 3, the variable stiffness device 200 is connected to the gripper controller 400, and the variable stiffness device 200 is provided by the stiffness control unit 420 of the gripper controller 400. The stiffness of can be adjusted. When the displacement measuring means 132 is connected to the gripper controller 400 and the gripper part 300 is deformed due to an assembly error, etc., when the component is inserted for assembling the parts, the displacement measuring means 132 uses the values measured by the displacement measuring means 132. The displacement calculation unit 410 of the gripper controller 400 may calculate the position of the bottom of the gripper unit 300, thereby determining whether the gripper unit 300 is deformed to the extent that the component can be inserted smoothly. Can be.

As such, the degree or shape of deformation may be determined according to the position of the bottom of the gripper part 300 calculated by the displacement calculation part 410 of the gripper controller 400, so that the rigidity calculation part may be easily assembled using the same. The stiffness suitable for assembly may be calculated at 430, and the stiffness of the variable stiffness device 200 may be adjusted and changed through the stiffness adjusting unit 420 according to the calculated stiffness.

In addition, the gripper controller 400 is connected to the robot controller 2200 for controlling the movement path and the position of the robot 2000, and according to the displacement of the lower end of the gripper 300 calculated by the displacement calculator 410. The robot controller 2200 may provide a target movement path and a target position of the robot 2000.

That is, the position of the bottom of the gripper unit 300 is calculated based on the displacement values calculated by the displacement calculator 410 of the gripper controller 400, and the position error is calculated using the position of the robot 2000 as the robot controller 2200. The target movement path and target position can be sent.

Meanwhile, as will be described later, the position target error of the gripper part received from the displacement calculator 410 may be calculated by the robot controller 2200 to calculate a position teaching error, and the next target movement path and the target position of the robot 2000 may be modified.

4 and 5 are assembled and exploded perspective views showing the passive rigid gripper of Figure 2; FIG. 6 is an exploded perspective view of the Stuart platform in the passive rigid gripper of FIG. 2. FIG. 7 and 8 are perspective and front views illustrating a state in which the stewart platform and the balloon are assembled in the manual rigid gripper of FIG. 2. FIG. 9 is a schematic view showing displacement along a linear stretch of a leg in the Stewart platform of FIG. 6.

4 to 9, in the manual rigid gripper 1000, the manual rigid part 100 may be a stewart platform as an example, and the variable rigid device 200 may be a balloon that can change the rigidity. Can be.

Accordingly, in the case described with reference to FIGS. 4 to 9, the passive rigid portion is called the Stuart platform 100 and the variable rigidity device is called the balloon 200.

Accordingly, hereinafter, the passive rigid portion is called the Stuart platform 102 and the variable rigidity device is called the balloon 200.

That is, in the passive rigid gripper 1002, the stewart platform 102 includes an upper structure 110 and a lower structure 120 spaced apart from the lower structure 110.

In this case, both ends are connected to the upper structure 110 and the lower structure 120 may be provided with a plurality of legs 130 are formed to be elastic, the leg 130, the displacement measuring means described above ( 132 may be installed.

In addition, the balloon 200 is disposed in the interior of the stewart platform 102, it may be an elastic material formed to be able to adjust the pneumatic pressure.

In addition, the gripper part 300 is coupled to the lower structure 120 of the Stuart platform 102 and grips a part.

More specifically, in the Stuart platform 102, the upper structure 110 may be formed in a disc shape, the upper surface may be coupled to the end of the arm 2100 of the robot (2000). In addition, the upper structure 110 has a plurality of coupling holes formed on the upper surface of the female screw thread is formed to be firmly coupled to the end of the arm 2100 by fastening means.

The lower structure 120 may also be formed in a disc shape, and the gripper unit 300 for holding a part to be assembled may be coupled to the lower surface.

Leg 130 is a portion connecting the upper structure 110 and the lower structure 120, the upper end of the leg 130 is connected to the lower surface of the upper structure 110 and the lower end is connected to the upper surface of the lower structure 120 Can be. In addition, the legs 130 may be formed to be elastic, and the lower structure 120 may be freely moved and rotated while the upper structure 110 is fixed.

In addition, the legs 130 may be disposed between the upper structure 110 and the lower structure 120, and may be disposed inside the edges of the upper structure 110 and the lower structure 120. That is, the legs 130 are disposed in the diameter range of the upper structure 110 and the lower structure 120, but may be disposed outside the center in the diameter range.

In addition, the legs 130 may be formed as six, for example, adjacent legs 130 may be disposed to be inclined in opposite directions to each other. That is, the two neighboring legs 130 may be arranged in the form of being connected to the upper structure 110 so that the upper ends are adjacent to each other and connected to the lower structure 120 so that the lower ends are adjacent to each other.

Thus, the Stewart platform 102 structure may be formed by the upper structure 110, the lower structure 120, and the plurality of legs 130.

The balloon 200 may be a spherical balloon of elastic material, and compressed air may be supplied or discharged to the inside to adjust the pneumatic pressure inside the balloon. At this time, the balloon 200 may be expanded or contracted as the compressed air is supplied or discharged to change its volume. When the compressed air is supplied, the pressure inside the balloon is increased and when the compressed air is discharged, the pressure inside the balloon may be decreased.

The balloon 200 may be disposed inside the stewart platform 102. That is, the balloon 200 may be disposed between the upper structure 110 and the lower structure 120 forming the Stuart platform 102 structure, such that the upper side and the lower side of the balloon 200 may be in close contact with each other. 130 may be arranged in the form surrounded by. In this case, the balloon 200 is preferably spaced apart from the legs 130 so that the balloon 200 does not come into contact with the legs 130 even when the balloon 200 is inflated.

The gripper part 300 is a part capable of holding a part to be assembled, and is formed to hold a part by being coupled to the finger block 310 and the finger block 310 which are coupled to the lower surface of the lower structure 120. And a pair of fingers 320.

In this case, the finger 320 may have a structure that can be caught or laid by opening or contracting, and as an example, the fingers 320 may be coupled to a structure in which the fingers 320 slide along the finger block 310. In addition, an actuator may be installed in the finger block 310 to open or pinch the pair of fingers 320, or the finger 320 may be configured to operate in various structures.

For example, when a component is inserted into a hole of an assembly object to be assembled, first, the component to be inserted is held by the finger 320 and moved to a position where a fixed component is located.

Thereafter, when the component to be inserted into the fixed component is inserted, the gripper unit 300 and the position error between the two components, the central axis is not coincident and misaligned, or there is an error in the insertion direction. The lower structure 120 is inserted while being moved together in the horizontal direction, or the lower structure 120 is bent by an angle α with respect to the upper structure 110 so that the gripper part 300 is inserted with respect to the vertical axis or the vertical axis is inserted. Can be inserted twisted to the center.

At this time, since the rigidity of the gripper part 300 depends on the internal pressure of the balloon 200 which is disposed inside the stewart platform 102 and is in close contact between the upper structure 110 and the lower structure 120, the balloon ( If the rigidity is increased by increasing the pressure of 200), the compliance is lowered, so that the parts can be inserted and assembled only when there is a small position error.On the contrary, if the rigidity is reduced by lowering the pressure of the balloon 200, the compliance is increased. Even when the error is large, the part may be easily inserted while the gripper part is changed in position or direction.

Here, compliance is a material constant expressed as a ratio of bending and deformation forces as described above. In this embodiment, the lower structure 120 that is movable relative to the fixed upper structure 110 is deformed (moved or rotated) by an external force. It can be a quantity indicating the degree to which it is likely to occur.

Accordingly, since the rigidity of the gripper may be adjusted by adjusting the pneumatic pressure of the balloon 200, the manual rigid gripper 1002 may be an assembly robot for assembling components having a large assembly error or assembly robots for assembling small components. It can be used in various ways and can be applied to various assembly such as vertical direction and horizontal direction.

In addition, even when the assembly error is large, the assembly can be made easily, even if it is difficult to align the position with the naked eye of the user has the advantage that the user can safely and easily teach the assembly.

More specifically, the gripper 300 including the lower structure 120 is moved in the X, Y, and Z axis directions, which are three-dimensional axes, and θ _X , θ _Y , and θ _Z , which are rotation directions about the three-dimensional axis. Stewart platform 100 may be formed to enable rotation in the direction. Thus, when the assembly of the parts, the gripper unit 300 is moved in the axial direction due to an assembly error or the like, and the assembly may be assembled while the position is changed or rotated around the shaft to be assembled.

At this time, the legs 130 may be made to include a displacement measuring means 132, respectively, so as to measure the length that changes depending on the linear stretch. In addition, since the manual rigid gripper 1000 includes a gripper controller 400 to which the displacement measuring means 132 are connected, the gripper controller 400 includes a gripper part through the displacements measured by the displacement measuring means 132. The position of the gripper may be controlled by calculating a position at the bottom of the 300.

That is, the displacement measuring means 132 is connected to the gripper controller 400, and when the gripper part 300 is deformed due to an assembly error, etc. when the component is inserted, the measured values are measured by the displacement measuring means 132. The gripper controller 400 may calculate the position of the bottom of the gripper unit 300, and the position teaching error may be corrected using the calculated position value of the bottom of the gripper unit 300.

In addition, a cover of a flexible material may be coupled to the circumferential surfaces of the upper structure 110 and the lower structure 120 to surround the outside of the legs 130.

As described above, the manual rigid gripper 100 used in the assembly control method according to the present embodiment has been described in detail. Hereinafter, the assembly control method using the manual rigid gripper 100 will be described in detail.

10 is a flowchart illustrating an assembly control method using the passive rigid gripper of FIG. 2 according to an embodiment of the present invention. FIG. 11 is a front view illustrating a state in which centers between the insertion holes of the first and second parts to be assembled do not coincide with each other when the robot is moved to the target position through the position shifting step of FIG. 10. 12 and 13 are front views illustrating a state in which the first part is assembled into the insertion hole of the second part while the manual rigid gripper is deformed through the assembling state determining step of FIG. 10. 14 and 15 show that the robot moves to the corrected target position through the assembly strategy modification step and the reassembly performing step of FIG. 10 in a state where the centers of the insertion holes of the first and second parts to be assembled coincide. The front view which shows the state assembled.

10 to 15, in the assembly control method using the manual rigid gripper according to the present embodiment, the first component 10 held by the manual rigid gripper 1000 is attached to the second component 20 to be assembled. Position movement step of moving the robot along a pre-input path to be moved to an adjacent position (S10), while obtaining the displacement information of the manual rigid gripper 1000 while assembling the first part 10 and the second part 20 An assembly strategy modification step of changing the path of the robot 2000 or the rigidity of the manual rigid gripper 1000 based on the assembly state determining step S20 and the information identified in the assembly state determining step S20. (S30).

First, in the position movement step (S10), as shown in Figure 11, in advance in the state in which the first component 10 is gripped by a manual rigid gripper 1000 mounted at the end of the arm 2100 of the robot 2000. The robot 2000 is automatically moved along the input path so that the first part 10 is moved to an adjacent position spaced apart from the upper side of the insertion hole 21 of the second part 20.

In this case, the robot controller 2200 is pre-input and stored the path and the position to move the robot 2000 for assembly, and the arm 2100 and the arm 2100 of the robot 2000 by the control signal of the robot controller 2200 The manual rigid gripper 1000 can be moved and operated.

In the assembling state determining step S20, as shown in FIGS. 12 and 13, the robot 2000 is operated so that the assembly may be performed while the first part 10 is inserted into the insertion hole of the second part 20. In addition, the assembly state of the passive rigid gripper 1000 is acquired in the process of assembling, thereby determining the assembly state of whether the assembly is performed smoothly.

Although not shown as an example, when the robot 2000 is operated and the manual rigid gripper 1000 is moved downward to assemble the first component 10 and the second component 20, the first component 10 may be moved. When the center position and the center position of the insertion hole 21 of the second part 20 coincide, the relative displacement error between the first part 10 and the second part 20 is small, so that the manual rigid gripper 1000 It can be assembled smoothly in a state where the deformation amount of is not large.

At this time, the assembly may be determined to be a normal normal assembly state based on the deformation amount of the manual rigid gripper 1000 and the tracking command tracking degree of the robot.

Unlike this, as shown in FIGS. 12 and 13, the center position of the first part 10 and the center position of the insertion hole 21 of the second part 20 do not coincide with each other, but may be inserted and assembled while contacting. In this case, deformation occurs according to the size of the rigidity set in the manual rigid gripper 1000. Therefore, at this time, it is not a normal assembly state through the displacement information of the passive rigid gripper 1000 can be determined as a state that can be assembled by pressing.

In addition, although not shown, when the center position of the first part 10 and the center position of the insertion hole 21 of the second part 20 do not coincide completely and thus cannot be inserted and assembled, manual stiffness is performed during the assembly process. Deformation occurs in the gripper 1000, but displacement occurs only in the vertical direction. Therefore, at this time, it can be determined as a state that can not be assembled.

In addition, depending on the displacement amount of the manual rigid gripper 1000 and the degree of following the position command of the robot, an assembly state such as jamming or wedging may be determined.

Thereafter, in the assembly strategy modification step (S30), based on the displacement information according to the deformation of the manual rigid gripper 1000, which is the state information identified in the assembly state identification step (S20), the path of the robot 2000 or A step of changing the rigidity of the passive rigid gripper 1000 is performed.

That is, when the center position of the first part 10 and the center position of the insertion hole 21 of the second part 20 coincide with each other, it may be in a normal assembly state, so that the path of the robot 2000 and the manual rigid gripper ( Since no stiffness change of 1000) is required, the assembly can be performed without modification of the assembly strategy.

12 and 13, when it is determined that the passive rigid gripper 1000 can be assembled while being deformed, the robot may be displaced using the displacement information of the manual rigid gripper 1000. Smooth assembly by changing the path of 2000 or by adjusting the rigidity of the manual rigid gripper 1000 according to the degree of deformation of the manual rigid gripper 1000 through the displacement information of the manual rigid gripper 1000. Assembly can be done and the path of the robot and the rigidity of the manual rigid gripper can be changed together.

Furthermore, when the assembly state is a state that cannot be assembled even if the manual rigid gripper 1000 is deformed as described above, the path of the robot 200 is moved to a position where assembly can be made by changing the path of the robot 2000. In this case, it is also possible to control the rigidity of the manual rigid gripper (1000) to ensure a smooth assembly.

On the other hand, the assembly control method using the manual rigid gripper 1000 according to the present embodiment, reassembly based on the path of the robot 2000 or the rigidity of the manual rigid gripper 1000 changed in the assembly strategy modification step (S30). It may further include a reassembly performing step (S40) to perform.

That is, the reassembly performing step (S40) may be performed after the assembly strategy modification step (S30), as shown in FIGS. 14 and 15, in the changed position or the manual rigid gripper 1000 of the robot 2000, which may be smoothly assembled. Reassembly is performed with the changed stiffness.

Thus, by performing the reassembly in the changed position or rigidity, the assembly is made smoothly in the changed state.

On the other hand, the reassembly step (S40) may be repeated several times.

That is, the reassembly performing step (S40) may be performed only once, but may be performed repeatedly several times to improve the assembly speed and accuracy.

Meanwhile, the reassembly performing step S40 may be performed for reassembly of the corresponding parts that have undergone the position shifting step S10 to the assembly strategy modification step S30. It may also be carried out for assembly to the part.

As described above, in the assembly control method using the manual rigid gripper according to the present embodiment, assembling can be performed by grasping the state of assembly during assembly work and modifying the path of the assembly position or changing the rigidity of the manual rigid gripper to make the assembly more smoothly. It has the advantage of improving speed and assembly quality.

In addition, when the assembly is completed by changing the path of the robot 2000 or the rigidity of the manual rigid gripper 1000 as described above, the assembly is made or changed according to the changed path when the assembly or the next assembly is performed. Assembly can be performed with the rigidity of.

Hereinafter, an assembly teaching method using a manual rigid gripper according to another embodiment of the present invention will be described, but the manual rigid gripper used in the assembly teaching method will be described first.

That is, FIGS. 16 and 17 are conceptual views illustrating a passive rigid gripper used in an assembly teaching method according to another embodiment of the present invention.

The passive rigid gripper 1001 is mounted to the arm 2100 of the robot 2000, as shown in FIG. 1, and the manual rigid gripper 1001 is formed to enable the adjustment of the rigidity and the displacement is measured. Can be.

That is, the manual rigid gripper 1001 is mounted at the end of the arm 2100 so that the first component 10 can be gripped, and the manual rigid gripper 1001 is formed to enable the adjustment of the rigidity. As a result, compliance may change. In addition, the passive rigid gripper 1001 can be measured a displacement that changes according to the deformation in the axial direction or the rotation (bending or twisting) about the axis.

More specifically, referring to FIGS. 16 and 17, the passive rigid gripper 1001 forms rigidity between both sides to allow deformation of the other side in a state where one side is fixed, and a manual rigid part that can adjust the formed rigidity. 100 is installed in the passive rigid portion 100, the variable stiffness device 200 for changing the rigidity, is installed in the passive rigid portion 100, it is possible to measure the displacement due to the deformation of the passive rigid portion 100 Displacement measuring means 132, and the gripper mounting portion 122 is formed on the other side of the passive rigid portion 100, the gripper portion 300 for holding the component can be mounted.

That is, the manual rigid gripper 1001 is provided with a variable stiffness device 200 that can change the stiffness in the manual stiffness part 100, the stiffness of the variable stiffness device 200 can be changed through the manual stiffness part 100. According to the rigidity of the variable stiffness device 200 to be changed, the manual stiffness part 100 may be controlled to be easily deformed or difficult to deform. In this case, the passive rigid portion 100 may be configured in various forms that can adjust the rigidity of the variable rigidity device 200.

In addition, the variable stiffness device 200 may be formed to be able to change the rigidity while having a specific rigidity, for example, may be composed of an elastic body such as a spring and the means for changing the rigidity of the elastic body. Thus, if the rigidity of the variable stiffness device 200 becomes large, the compliance of the passive rigid gripper becomes small, whereas if the rigidity decreases, the compliance becomes large.

Referring again to FIGS. 16 and 17, the manual rigid gripper 100 further includes a gripper controller 400 to which the variable rigidity device 200 and the displacement measuring means 132 are connected.

The gripper controller 400, the position of the bottom of the gripper unit 300 through the stiffness control unit 420, which can adjust the stiffness of the variable stiffness device 200, and the displacements measured by the displacement measuring means 132 It includes a displacement calculation unit 410 for calculating the.

More specifically, as shown in FIGS. 16 and 17, the variable stiffness device 200 is connected to the gripper controller 400, and the variable stiffness device 200 is provided by the stiffness control unit 420 of the gripper controller 400. The stiffness of can be adjusted. When the displacement measuring means 132 is connected to the gripper controller 400 and the gripper part 300 is deformed due to an assembly error, etc., when the component is inserted for assembling the parts, the displacement measuring means 132 uses the values measured by the displacement measuring means 132. The displacement calculation unit 410 of the gripper controller 400 may calculate the position of the bottom of the gripper unit 300, thereby determining whether the gripper unit 300 is deformed to the extent that the component can be inserted smoothly. Can be.

Thus, if it is judged that there is an assembly error of a degree that the component cannot be inserted smoothly or is very difficult to be inserted, the robot can be moved to the corrected position when the next assembly is corrected.

In addition, the gripper controller 400 is connected to the robot controller 2200 that controls the movement path and the position of the robot 2000, and the gripper controller 400 calculates the gripper unit 300 calculated by the displacement calculator 410. According to the displacement of the lower end, the robot controller 2200 may provide a target movement path and a target position of the robot 2000.

Unlike this, the robot controller 2200 may calculate a position error from the position information of the lower end of the gripper part received from the displacement calculator 410, thereby modifying the next target movement path and the target position of the robot 2000.

On the other hand, in the manual rigid gripper 1001, as described with reference to Figures 4 to 9, the passive rigid portion 100 may be a stewart platform as an example, the variable rigidity device 200 changes the rigidity It can be a balloon that can be.

Accordingly, the Stewart platform 100 described with reference to FIGS. 4 to 9 as an example of the passive rigid portion, and the balloon 200 described with reference to FIGS. 4 to 9 as an example of the variable rigidity device are shown in this embodiment. The same applies to the manual rigid gripper 1001 used in the assembling teaching method. Therefore, redundant description is omitted.

FIG. 18 is a flowchart illustrating an assembly teaching method using the passive rigid gripper of FIG. 16 according to another embodiment of the present disclosure. FIG. 19 is a front view illustrating a state in which centers between the insertion holes of the first and second parts to be assembled do not coincide with each other when position information is provided to the robot through the location information storing step of FIG. 18. 20 is a perspective view illustrating a state in which an external force is applied to the entire robot through the additional moving step of FIG. 18. 21 and 22 are front views illustrating a state in which an external force is applied to the lower side of the gripper to insert the first part into the insertion hole of the second part through the additional moving step of FIG. 18.

18 to 22, the assembling teaching method using the manual rigid gripper according to the present embodiment includes placing the first component 10 held by the manual rigid gripper 1001 on the second component 20 to be assembled. The position information storage step (S11) of moving the robot 2000 to move to an adjacent position and storing the position information of the manual rigid gripper 1001, and the external component is applied to hold the first component 10 A further movement step S21 in which the position of the passive rigid gripper 1001 is deformed or additionally moved to be assembled to the second component 20, and the manual rigid gripper 1001 in the further movement step S21. Based on the error calculation step (S31) for acquiring the position information of the position information and calculating the position error with the position information in the position information storing step (S11), and the error calculation step (S31), In the location information storage step (S11) And a location information correction step (S41) of modifying the position information of the passive rigid gripper 1001. First, in the position information storing step (S11), as shown in FIG. 19, an operator teaches the robot 2000 to move the robot to a position immediately before the first part 10 is assembled to the second part 20. 2000). In this case, the operator controls the robot 2000 by using a teaching pendant to teach the path and the location where the robot 2000 is moved, and the path and the location information are thus stored.

In this case, the manual rigid gripper 1001 is mounted at the end of the arm 2100 of the robot 2000, and the first component 10, which is a component to be assembled by the finger 320 of the manual rigid gripper 1001, may be gripped. . Thus, the position of the robot 2000 can be taught to hold the first part 10 with the passive rigid gripper 1001 and then move to an adjacent position just before being inserted into the second part 20 and assembled.

As shown in FIG. 19, the position immediately before assembly is spaced apart from the upper side of the portion where the insertion hole 21 of the second component 20 is formed, and thus the first component 10 is disposed. When moved downward, the position can be inserted into the insertion hole 21 of the second component 20. At this time, the position information including the movement path of the robot 2000 operated by the position teaching of the operator may be stored in the robot controller 2200.

Thereafter, in the additional movement step S21, as the additional movement is performed as illustrated in FIG. 20 or 21, the first component 10 is inserted into the insertion hole 21 of the second component 20. As the assembly is performed, as the external force is applied, a displacement of the passive rigid gripper lower structure is generated to be assembled to the second component 20, or the robot 2000 is further moved by using the generated displacement information. , Assembly can be made.

In this case, the applied external force may be applied by an operator or the like, and as illustrated in FIG. 20, the robot may further move the entire robot 2000 by using the displacement of the manual rigid gripper 1001 generated by the external force. The order can be made.

In contrast, the applied external force is applied to the end of the passive rigid gripper 1001 holding the first component 10, as shown in FIG. 21, so that the position of the passive rigid gripper 1001 is adjusted. It may be moved further.

More specifically, when the external force is applied to the end of the passive rigid gripper 1001, the first part 10 before the first part 10 is inserted into the insertion hole 21 of the second part 20. The rigidity of the manual rigid gripper 1001 gripping) is adjusted to be lower so as to have a higher compliance.

Thus, the robot 2000 is moved downward so that the lower end of the first part 10 contacts the upper part of the insertion hole 21 of the second part 20 or the upper surface of the second part 20. The manual rigid gripper is directly taught by applying an external force to the lower side of the gripper part 300 using an or tool. Accordingly, the passive rigid gripper is induced to deform and start to be inserted in an inclined state, after which the gripper part is moved to be inserted in a vertical state to be assembled.

On the other hand, it is direct teaching that the manual rigid gripper (the whole robot in FIG. 20) is deformed by applying an external force to the gripper 300 (the whole robot in FIG. 20) using a worker's hand or a tool. The gripper 300 (the entire robot in FIG. 20) may be modified in various degrees of freedom, such as movement or rotation in the vertical direction as well as in the lateral direction.

Thus, as shown in FIG. 19, even if there is a position error between the position of the first part 10 and the insertion hole 21 of the second part 20, the manual rigid gripper 1000 may be caused by the high compliance of the manual rigid gripper 1000. The first part 10 may be more easily inserted and assembled into the insertion hole 21 of the second part 20 while the 1000 is easily deformed and a displacement occurs.

On the other hand, when there is an assembly position error between the first part 10 and the insertion hole 21 of the second part 20 in the additional movement step (S21), the first part 10 is the second part ( The displacement information of the passive rigid gripper 1000 may be obtained from the deformation of the passive rigid gripper 1000 which is inserted into the insertion hole 21 of the 20 and capable of sensing the displacement.

That is, the displacement information of the passive rigid gripper in the process of inserting the component may be obtained, and the displacement information of the passive rigid gripper may be obtained when the insertion of the component is completed.

Thus, in the error calculation step (S31), the displacement information and the position of the manual rigid gripper 1000 using the obtained displacement information of the manual rigid gripper and the position information of the robot taught and stored in the position information storage step (S11). In the information storing step S11, a position error between the stored position information of the robot 2000 may be calculated.

Thereafter, in the position information correcting step (S41), as a step of modifying the position information of the manual rigid gripper 1001 by modifying a position teaching command so that the position error calculated in the error calculating step S31 is removed, The robot is actually moved to a position where the assembly can be made smoothly.

Thus, if the position of the robot using the position information modified through the position information correction step (S41) can be assembled at a more accurate position during the next assembly.

In this case, the position information modified through the position information correction step S41 may be applied at the time of assembling, and may perform the assembly in the assembling process.

On the other hand, in the assembly teaching method according to the present embodiment, based on the position information modified through the position information correction step (S41), the robot 2000 is moved to move the first component 10 to the second component. The assembly 20 may further include a reassembly performing step (S51).

That is, when the teaching instruction is performed based on the position information modified through the position information correcting step (S41), as described with reference to FIGS. 14 and 15, the first part 10 and the second part 20. ) Can be reproduced more smoothly, and this assembly can be performed several times.

Furthermore, the assembly teaching method described above may be applied and performed immediately in the assembly step, or may be applied in a subsequent assembly step based on the information modified in the assembly step.

In addition, as a plurality of assembling steps are repeatedly performed, the positional information can be continuously updated, whereby the accuracy in assembly can be further improved.

As described above, the assembly teaching method using the manual rigid gripper according to the present embodiment can provide rigidity that can cope with the positional error and the processing tolerance of the workpiece at the time of assembly, and can be applied to various assemblies. There is an advantage that can be applied to a variety of assembly, such as direction and horizontal direction. In addition, there is a high applicability to various robots, there is an advantage that the user can perform a safe and easy assembly.

The present invention is not limited to the above-described embodiments, and the scope of application of the present invention is not limited to those of ordinary skill in the art to which the present invention pertains without departing from the gist of the present invention as claimed in the claims. Of course, various modifications can be made.

Claims

A position moving step of moving the robot along a pre-input path to move the first part held by the manual rigid gripper to a position adjacent to the second part to be assembled;

An assembling state determining step of assembling the first part and the second part to determine the assembling state by obtaining displacement information of the passive rigid gripper; And

And an assembly strategy modification step of changing the path of the robot or the rigidity of the manual rigid gripper based on the information identified in the assembly state determining step.
The method of claim 1,

And a reassembly performing step of performing reassembly based on the path of the robot or the rigidity of the manual rigid gripper changed in the assembly strategy modification step.
The method of claim 2,

The reassembly performing step is repeated assembly control method using a manual rigid gripper, characterized in that repeatedly performed.
A position information storage step of moving the robot to move the first component held by the manual rigid gripper to a position adjacent to the second component to be assembled, and storing position information of the manual rigid gripper;

If the moved position is not accurate and additional movement is required, as the external force is applied, the further movement is modified or additionally moved so that the position of the passive rigid gripper holding the first component is assembled to the second component. step;

An error calculating step of obtaining position information of the passive rigid gripper in the further moving step and calculating a position error with the position information in the position information storing step; And

And a position information correcting step of correcting position information of the passive rigid gripper in the position information storing step, based on the position error calculated in the error calculating step.
The method of claim 4, wherein

Based on the position information modified through the position information correction step, the assembly using the manual rigid gripper, characterized in that further comprising the step of reassembling the assembly of the first part to the second part by moving the robot. Teaching method.
The method of claim 5, wherein in the further moving step,

Assembly instruction method using a manual rigid gripper, characterized in that the additional movement command is applied to the entire robot by using the displacement of the manual rigid gripper generated by the external force.
The method of claim 5, wherein in the further moving step,

And an external force is applied to an end of the passive rigid gripper holding the first component to generate a displacement of the lower structure of the passive rigid gripper to be assembled to the second component.
The method of claim 7, wherein in the further moving step,

Assembly rigid teaching method using a manual rigid gripper, characterized in that to change the rigidity of the passive rigid gripper holding the first component relatively low.
The method according to claim 1 or 4,

The passive rigid gripper is mounted to the arm of the robot,

The passive rigid gripper is an assembly control method using a manual rigid gripper, characterized in that the rigidity can be adjusted and the displacement is measured.
The method of claim 9, wherein the passive rigid gripper,

A passive stiffness portion which forms rigidity between both sides so that the other side can be deformed while one side is fixed, and which can adjust the rigidity;

A variable stiffness device installed in the passive stiffness part to change the stiffness;

Displacement measuring means installed in the passive rigid portion, the displacement measuring means capable of measuring displacement due to deformation of the passive rigid portion; And

And a gripper mounting part connected to the other side of the passive rigid part and equipped with a gripper part for holding a component.
The method of claim 10,

And a gripper controller connected to the variable stiffness device and the displacement measuring means.

The gripper controller,

A stiffness controller for adjusting the stiffness of the variable stiffness device;

A displacement calculation unit calculating a position of a lower end of the gripper unit based on the displacement measured by the displacement measuring unit; And

Assembly rigidity control method using a manual rigid gripper, characterized in that it comprises a stiffness calculator connected to the stiffness control unit and the displacement calculator.
The method of claim 11, wherein in the gripper controller,

Assembly control using a manual stiffness gripper, characterized in that the stiffness calculator calculates the stiffness based on the position of the lower end of the gripper part calculated by the displacement calculator to adjust the stiffness of the variable stiffness device through the stiffness control unit. Way.
The method of claim 11, wherein the gripper controller,

And a target movement path and a target position of the robot to the robot controller based on the position of the bottom of the gripper portion calculated by the displacement calculator.