WO2012176382A1

WO2012176382A1 - Robot hand with fully integrated exchangeable fingers

Info

Publication number: WO2012176382A1
Application number: PCT/JP2012/003578
Authority: WO
Inventors: Yoshiyuki Miyazaki
Original assignee: Canon Kabushiki Kaisha
Priority date: 2011-06-20
Filing date: 2012-05-31
Publication date: 2012-12-27
Also published as: JP5888884B2; JP2013000853A

Abstract

To provide a robot hand, which improves efficiency of maintenance work. A finger 10, electric motors 14 and 15, which drive the finger 10, a motor driver 16, which controls operation of the electric motors 14 and 15, and a finger base 13, which supports the finger 10, are integrally modularized. The finger base 13 is removably attached to an attaching unit 102 of a hand base 101. A power supply module 104, which outputs an operation command, is provided on the hand base 101. The motor driver 16 is connector-connected to the power supply module 104.

Description

[Title established by the ISA under Rule 37.2] ROBOT HAND WITH FULLY INTEGRATED EXCHANGEABLE FINGERS

The present invention relates a robot hand attached to an arm tip end and the like of an industrial robot to be used when gripping a component to assemble.

Recently, automated assembly of a small-sized product having a complicated structure such as a camera and a printer is increasingly required. The components used in such product are often small and in various shapes. In order to respond to this, a small-sized robot hand capable of gripping pieces of work of various types and of performing assembly work of the various pieces of work is required.

Also, the robot hand is required to continuously operate, so that a large load is applied to a finger of the robot hand. Therefore, it is required to rapidly exchange at the time of maintenance when the finger is broken, failed and the like.

For this, technology to compose a finger module by integrally providing two fingers and an electric motor, which drives the fingers, on a finger base and making the finger module attachable to and removable from the hand base is disclosed (refer to PTL 1). A connector used for supplying electrical power and outputting a signal to the electric motor is provided on the finger base disclosed in PTL 1. Therefore, the motor driver, which supplies the electrical power to the electric motor, is provided on a side of the hand base. That is to say, the finger module and the motor driver are separated from each other.

PTL 1: Japanese Patent Application Laid-Open No. 2007-222971

In the conventional configuration, however, it is required to regulate an existing motor driver in accordance with a newly connected finger module when it becomes necessary to exchange the finger module by fail, break and the like of the finger, so that maintenance work takes time.

It is also considered to exchange the motor driver together with the finger module without regulating the existing motor driver. However, it is required to perform attachment work with attention not to change a corresponding relationship between the new finger module and the new motor driver. Moreover, attachment/removable work of the motor driver is also required in addition to the attachment/removable work of the finger module, so that the maintenance work takes time.

Therefore, an object of the present invention is to provide the robot hand, which improves efficiency of the maintenance work.

A robot hand of the present invention is provided with: a finger module obtained by integrally modularizing a finger, an electric motor, which drives the finger, a motor driver, which supplies electrical power to the electric motor and controls operation of the electric motor based on an input operation command, and a finger base, which supports the finger; a hand base on which an attaching unit to which the finger base is removably attached is formed; and a controller provided on the hand base to be connector-connected to the motor driver, which outputs the operation command to operate the electric motor to the motor driver.

According to the present invention, the finger, the electric motor, and the motor driver are integrated with each other in the finger module. According to this, when it is required to exchange the finger module, it is not required to perform regulation work of the motor driver at the time of maintenance work by regulating the motor driver in advance in the new finger module. Therefore, it is possible to rapidly perform the maintenance work to exchange the finger module, thereby improving efficiency of the maintenance work.

Also, since the motor driver is integrated with the finger module, it is not required to independently perform the attachment/removable work of the motor driver. Connection work of the controller and the motor driver may be performed by connector-connection, so that the work is simplified and efficiency of the maintenance work is improved.

Fig. 1 is an illustrative diagram illustrating a schematic configuration of a robot hand according to a first embodiment of the present invention. Fig. 2A is a side view of a finger module in a state of being removed from a hand module. Fig. 2B is a front view of the finger module in a state of being removed from the hand module. Fig. 3 is an illustrative diagram of a method of attaching the finger module to the hand module in the robot hand according to the first embodiment of the present invention. Fig. 4A is a schematic top view of a robot hand according to a second embodiment of the present invention in a state in which a finger is removed therefrom. Fig. 4B is a schematic top view of the robot hand according to the second embodiment of the present invention including two fingers. Fig. 4C is a schematic top view of the robot hand according to the second embodiment of the present invention including three fingers. Fig. 4D is a schematic top view of the robot hand according to the second embodiment of the present invention including four fingers. Fig. 5 is a perspective view of a substantial part of a robot hand according to a third embodiment of the present invention. Fig. 6 is a schematic top view of the robot hand according to the third embodiment of the present invention.

Hereinafter, an embodiment for carrying out the present invention is described in detail with reference to the drawings.

First Embodiment

Fig. 1 is an illustrative diagram illustrating a schematic configuration of a robot hand according to a first embodiment of the present invention. A robot hand 200 illustrated in Fig. 1 is configured to grip work. The robot hand 200 is provided with a plurality of finger modules 50. In the first embodiment, the robot hand 200 is provided with two

finger modules

50₁ and 50₂. The robot hand 200 is also provided with a hand module 100 as a hand main body. The

finger modules

50₁ and 50₂ are configured to be attachable to and removable from the hand module 100.

First, a configuration of each of the

finger modules

50₁ and 50₂ is described. Meanwhile, the

finger modules

50₁ and 50₂ have a similar configuration and the

finger modules

50₁ and 50₂ are hereinafter described as the finger modules 50. Figs. 2A and 2B are illustrative diagrams illustrating the finger module 50 in a state of being removed from the hand module 100 in which Fig. 2A is a side view of the finger module 50 and Fig. 2B is a front view of the finger module 50.

The finger module 50 illustrated in Figs. 2A and 2B is provided with one finger 10 obtained by pivotably coupling a plurality of (two, in the first embodiment)

link members

11 and 12 and a planer finger base 13, which supports the finger 10. It is configured such that the work is gripped by a plurality of (two, in this embodiment) fingers 10. The finger module 50 is also provided with

electric motors

14 and 15, which drive the finger 10. Specifically, the first electric motor 14 drives the first link member 11 and the second electric motor 15 drives the second link member 12.

Further, the finger module 50 is provided with a motor driver 16, which supplies electrical power to the

electric motors

14 and 15 and controls operation of the

electric motors

14 and 15 based on an input operation command. The

electric motors

14 and 15 are fixed to a surface of the finger base 13 on a side opposite to a surface, which supports the finger 10. The motor driver 16 is a control board composed of a wiring board and a semiconductor element mounted on the wiring board and is fixed to the

electric motors

14 and 15. According to this, the finger 10, the

electric motors

14 and 15, the motor driver 16, and the finger base 13 are integrally modularized to compose the finger module 50.

The first link member 11 of the finger 10 is a middle phalanx of which base end is a first joint 21 and is pivotably coupled to the finger base 13 at the first joint 21. Also, the second link member 12 is a fingertip of which base end is a second joint 22 and is pivotably coupled to a tip end of the first link member 11 at the second joint 22.

A belt pulley 23 is arranged on the first joint 21 and a belt pulley 24 is arranged coaxially with the second joint 22. The belt pulleys 23 and 24 are connected to each other by a belt 25.

First, when the first electric motor 14 is rotated, rotation drive force thereof is transmitted through a gear and the like not illustrated and the first link member 11 pivots at the first joint 21. On the other hand, when the second electric motor 15 is rotated, drive force thereof is transmitted to the belt pulley 23, the belt pulley 24 rotates by means of the belt 25, and the second link member 12 pivots at the second joint 22 through a gear and the like not illustrated fixed coaxially with the second joint 22.

Rotary encoders

26 and 27 are provided on the

electric motors

14 and 15, respectively. The

rotary encoders

26 and 27 are connected to the motor driver 16 by a cable not illustrated to detect rotation of the electric motors 14 and 15 (rotational shafts of rotators), respectively. The motor driver 16 always monitors a rotation speed, a rotation position, and a rotation amount from detection results of the

rotary encoders

26 and 27 to control drive of the

electric motors

14 and 15. Also, the motor driver 16 is connected to both of the

electric motors

14 and 15 by a cable not illustrated for supplying the electrical power to both of the

electric motors

14 and 15.

The motor driver 16 is provided with a cable 28 for electrically connecting to a power supply module 104 (refer to Fig. 1). The cable 28 is provided with a connector unit 29 for connector-connecting to connector-connecting units 104a to 104d of the power supply module 104 on a tip end thereof.

Next, the hand module 100 is described. As illustrated in Fig. 1, the hand module 100 is provided with a planar hand base 101 to which the finger base 13 of the finger module 50 is fixedly attached. Since there are two fingers 10 in the first embodiment, two attaching units 102 for attaching the finger base 13 are formed on the hand base 101.

Also, the hand module 100 is provided with a hand casing 103 fixed to a surface of the hand base 101 on a side opposite to a surface to which the finger base 13 is attached. The power supply module 104 as a controller is fixedly arranged in the hand casing 103. The power supply module 104 is connected to an external controller not illustrated by a cable 30 for inputting an operation command of the robot hand 200 from the external controller not illustrated. The power supply module 104 has a function to supply the electrical power to the motor driver 16 of each of the finger modules 50 and to intercommunicate with each motor driver 16 and intercommunicate with the external controller not illustrated.

That is to say, the power supply module 104 outputs the operation command to operate the

electric motors

14 and 15 of each of the finger modules 50 to each motor driver 16 through the cable 28 based on the operation command of the robot hand 200 input from the external controller. Also, the power supply module 104 supplies the electrical power to each motor driver 16 through the cable 28. The motor driver 16 to which the operation command is input supplies the electrical power to the

electric motors

14 and 15 and controls the operation of the

electric motors

14 and 15 based on the input operation command.

Also, a plurality of (four, in Fig. 1) connector-connecting units 104a to 104d are provided on the power supply module 104. The cable 28 extending from the motor driver 16 of each of the

finger modules

50₁ and 50₂ is connector-connected to any one of the connector-connecting units 104a to 104d by means of the connector unit 29. Therefore, the connector unit 29 is attachable to and removable from the connector-connecting units 104a to 104d.

In this manner, each of the finger modules 50 of the robot hand 200 independently controls an electrical current value, an encoder command value and the like based on the command from the external controller not illustrated through the motor driver 16. Also, this is set to be able to grip a various pieces of work in various shapes by adjusting gripping force, a gripping speed, and an angle of joint while intercommunicating with the external controller not illustrated.

Although the finger module 50 of a bending rotary actuator, which drives one finger with two joints, is described in the first embodiment, this is not limited thereto. The actuator capable of operating to bend, to rotate, to extend and contract and the like may be selected according to an environment of usage such as a component and assembly work, a plurality of actuators may be included, and the finger module may be configured to be suitable for grip of the work and the assembly operation.

Next, the attaching unit 102 of the hand base 101 to which the finger base 13 of the finger module 50 is removably attached is described with reference to Fig. 3. A positioning hole 102a and a female screw hole 102b are formed on the hand base 101 as the attaching unit 102. A positioning boss 13a, which fits into the positioning hole 102a, and a through hole 13b through which a fastening member 13c such as a bolt being a male screw to be screwed into the female screw hole 102b is inserted are formed on the finger base 13. The positioning boss 13a of the finger base 13 fits into the positioning hole 102a of the hand base 101 and the fastening member 13c is screwed into the female screw hole 102b through the through hole 13b, and according to this, the finger base 13 is attached to the attaching unit 102. According to this, the finger module 50 is positioned to be fixed to the hand base 101. Then, by connecting the connector unit 29 to the connector-connecting unit 104a, the finger module 50 is attached to the hand module 100.

Meanwhile, when the finger base 13 is removed from the attaching unit 102, the fastening means 13c is loosen. Then, by removing the connector unit 29 from the connector-connecting unit 104a, it is possible to easily remove the finger module 50 from the hand module 100.

Then, in Fig. 1, when the finger module 50₁ is exchanged, for example, the finger base 13 of the finger module 50₁ is removed from the attaching unit 102 and the connector unit 29 is removed from the connector-connecting unit 104a. A new finger module 50₁ including a regulated motor driver 16 is prepared, the finger base 13 of the new finger module 50₁ is attached to the attaching unit 102 and the connecter unit 29 is connected to the connector-connecting unit 104a. Same applies to a case in which the finger module 50₂ is exchanged.

As described above, according to the first embodiment, the finger 10, the

electric motors

14 and 15, and the motor driver 16 are integrated with each other in the finger module 50. According to this, when it is required to exchange the finger module 50, it is not required to perform regulation work of the motor driver 16 at the time of maintenance work by regulating the motor driver 16 in advance in the new finger module 50. Therefore, it is possible to rapidly perform the maintenance work to exchange the finger module 50, thereby improving efficiency of the maintenance work.

Also, since the motor driver 16 is integrated with the finger module 50, it is not required to independently perform attachment/removable work of the motor driver 16. It is possible to perform cable connection work of the power supply module 104 and the motor driver 16 by connector-connection, so that the work is simplified and the efficiency of the maintenance work is improved.

Also, it becomes possible to shorten or eliminate calibration work to correct variation in the gripping force, the gripping speed and the like of each of the

finger modules

50₁ and 50₂ in the robot hand 200 after exchange, so that the efficiency of the maintenance work is significantly improved.

Second Embodiment

Next, a robot hand according to a second embodiment of the present invention is described. Figs. 4A to 4D are schematic top views of the robot hand in which Fig. 4A is the robot hand in a state in which a finger is removed therefrom. Figs. 4B, 4C, and 4D illustrate the robot hand including two fingers, the robot hand including three fingers, and the robot hand including four fingers, respectively. Meanwhile, a configuration of a hand module, which is a hand main body of the robot hand, except a hand base and a configuration of each finger module are similar to those in Figs. 1 to 3 described in the above-described first embodiment, so that a detailed description thereof is omitted.

In the second embodiment, as illustrated in Fig. 4A, each of attaching units 102A to 102H to which a finger base is attached is formed on a hand base 101A on each position corresponding to change in the number of fingers 10. Specifically, each of the attaching units 102A to 102H to which the finger base is attached is formed on the hand base 101A on each position corresponding to cases in which the number of the fingers 10 is two to four.

A configuration of each of the attaching units 102A to 102H is similar to that of the above-described first embodiment and the robot hand is composed by fixing a finger base 13 (refer to Fig. 3) of a finger module 50 to the attaching unit. Specifically, when the number of the fingers 10 is two, the finger bases are attached to the attaching

units

102C and 102G as illustrated in Fig. 4B. Also, when the number of the fingers 10 is three, the finger bases are attached to the attaching

units

102A, 102D, and 102F as illustrated in Fig. 4C. Also, when the number of the fingers 10 is four, the finger bases are attached to the attaching

units

102B, 102D, 102F, and 102H as illustrated in Fig. 4D.

Since four connector-connecting units 104a to 104d are provided on the power supply module 104 (refer to Fig. 1), a connector unit provided on a cable extending from a motor driver 16 of each finger module is connected to each connecter-connecting unit. According to this, an external controller not illustrated recognizes each finger module and operation of the robot hand becomes possible.

Meanwhile, a minimum configuration according to the number of the fingers of the robot hand may be constructed by making a center of the robot hand conform to a pivot center of the robot hand to minimize a circumscribed circle diameter.

As described above, according to the second embodiment, not only the number of the fingers 10 is changed but also the number of the motor drivers 16 is changed corresponding to the number of the fingers 10 by only changing the number of the finger modules, so that the number and arrangement of the fingers 10 are easily changed according to a work process.

In this manner, it is possible to easily construct the robot hand of various variations by allowing the fingers 10 to be attached to and removable from a dedicated hand base 101A corresponding to the number of the fingers 10 and making the number of the fingers 10 changeable in a unit of one finger.

Since the finger 10, the electric motor, and the motor driver are modularized, a suitable number of the fingers may be arranged according to target work. Further, it may be configured such that a pivot radius with respect to a robot arm is easily minimized, so that a small-sized robot hand capable of performing assembly work in a narrow assembly work space may be easily constructed.

Third Embodiment

Next, a robot hand according to a third embodiment of the present invention is described. Fig. 5 is a perspective view of a substantial part of the robot hand according to the third embodiment of the present invention and Fig. 6 is a schematic top view of the robot hand according to the third embodiment of the present invention. Meanwhile, an entire configuration of the robot hand is the same as that in Fig. 1, Figs. 2A and 2B, and Fig. 3 described in the above-described first embodiment and that in Figs. 4A to 4D described in the above-described second embodiment, so that a detailed description thereof is omitted.

As illustrated in Fig. 5, in a finger module 50, two

electric motors

14 and 15 are arranged on a finger base 13 and

encoders

26 and 27 are arranged on the

electric motors

14 and 15, respectively. Rotary switches (hereinafter, referred to as rotary SWs) 41 and 42, which give ID information for identification to the finger module 50, are arranged on the

encoders

26 and 27, respectively.

For example, as illustrated in Fig. 6, in the robot hand including four finger modules 50₁ to 50₄, pieces of ID information ID1 to ID4 are given to the finger modules 50₁ to 50₄, respectively.

As the ID information, the ID1 is given to the finger module 50₁ by setting the

rotary SWs

41 and 42 in Fig. 5 to positions "1" and "2", respectively, and setting "1" + "2" to the ID1. When the ID2 is given to the finger module 50₂ as the ID information, the

rotary SWs

41 and 42 are set to "3" and "4", respectively. When the ID3 is given to the finger module 50₃ as the ID information, the

rotary SWs

41 and 42 are set to "5" and "6", respectively. When the ID4 is given to the finger module 50₄ as the ID information, the

rotary SWs

41 and 42 are set to "7" and "8", respectively.

When the finger base 13 (Fig. 5) of each of the finger modules 50₁ to 50₄ to which the ID information is given is assembled to a hand base 101A, the finger base is attached to a predetermined attaching unit on the hand base 101A. Then, a cable 28 (Fig. 1) of each of the finger modules 50₁ to 50₄ is connected to an optional one of connector-connecting units 104a to 104d of the power supply module 104 (Fig. 1).

Thereafter, by activating an assembling robot station not illustrated on which the robot hand is installed, an external controller not illustrated automatically recognizes the pieces of the ID information of all the finger modules 50₁ to 50₄ connected to the robot hand. Then, the external controller not illustrated distinguishes configurations and the number of the finger modules 50₁ to 50₄ and automatically switches to control of a robot hand configuration, thereby enabling the control.

As described above, according to the third embodiment, an external computer may recognize the ID information of the finger module when the ID information inherent to each of the finger modules 50₁ to 50₄ is given and they are assembled to the hand base 101A of the robot hand. Then, the external computer may automatically identify a type, the number, and combination of the pieces of the ID information, thereby automatically switching to the control of the robot hand configuration corresponding to the configuration and the number of the finger modules. Therefore, change in setting of the control and regulation regarding the robot hand by a user are not required, so that switch work of the robot station may be smoothly performed.

Meanwhile, although the present invention is described based on the above-described first to third embodiments, the present invention is not limited thereto. Although the robot hand including two fingers is described in the above-described first embodiment, this is not limited thereto and this is also applicable to the robot hand including three or more fingers.

Also, although the robot hand including two to four fingers 10 changeable to make three variations is described in the above-described second embodiment, this is not limited thereto. The robot hand in which the number of arranged fingers and arrangement positions of the fingers (interdigital pitch and angle) are changed according to a shape and the like of a gripped target may be constructed.

Also, although the

rotary SWs

41 and 42 are arranged on the

rotary encoders

26 and 27, respectively, and the IDs are distributed to the finger modules 50 by combination of the pieces of the ID information allocated thereto in the above-described third embodiment, this is not limited thereto. It is also possible to provide a function to give the ID information on the finger module 50 such as the motor driver 16.

Also, although a case in which a connector unit 29 is provided on a tip end of the cable 28 extending from the motor driver 16 to be connector-connected to connector-connecting units 104a to 104d of the power supply module 104 is described in the above-described first to third embodiments, this is not limited thereto. It is also possible to provide the connector unit on the tip end of the cable extending from the power supply module 104 as a controller to connect the connector unit to the connector-connecting unit of the motor driver 16. It is also possible to provide the connector units on both ends of the cable to connect one connector unit to the connector-connecting unit of the motor driver 16 and to connect the other connector unit to the connector-connecting unit of the power supply module 104. Also, it is possible to directly connector-connect the motor driver 16 and the power supply module 104 to each other without the cable.

Also, although a case in which an attaching unit 102 is composed of a positioning hole 102a and a female screw hole 102b is described in the above-described first to third embodiments, this is not limited thereto. It is also possible to provide a positioning boss in place of the positioning hole 102a and to provide the positioning hole on the finger base. Also, a through hole through which a fastening member is inserted may be formed in place of the female screw hole 102b and in this case, it is possible to form the female screw hole on the finger base or it may be configured such that fastening is performed by means of a separately provided nut.

The present invention is applicable to the robot hand in automated assembly by an industrial robot.

10 finger
13 finger base
14, 15 electric motor
16 motor driver
28 cable
50 finger module
101 hand base
102 attaching unit
104 power supply module (controller)
200 robot hand

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

This application claims the benefit of Japanese Patent Application No. 2011-136321, filed June 20, 2011, which is hereby incorporated by reference herein in its entirety.

Claims

A robot hand, comprising:
a finger module obtained by integrally modularizing a finger, an electric motor, which drives the finger, a motor driver, which supplies electrical power to the electric motor and controls operation of the electric motor based on an input operation command, and a finger base, which supports the finger;
a hand base on which an attaching unit to which the finger base is removably attached is formed; and
a controller provided on the hand base to be connector-connected to the motor driver, which outputs the operation command to operate the electric motor to the motor driver.
The robot hand according to claim 1, wherein the attaching unit is formed on the hand base on each position corresponding to change in the number of fingers.
The robot hand according to claim 1 or 2, wherein ID information for identifying the finger module is given to the finger module.