JP7308324B1 - modular robot - Google Patents

Abstract

Kind Code: A1 A modular structure robot is provided in which each module can be easily attached and detached, and position information can be calibrated thereafter. A modular structure robot comprising a plurality of modules each constituting a functional part, wherein two modules adjacent to each other among the plurality of modules are detachably coupled to each other in a state of being roughly positioned by fitting portions provided in the modules, and for calibrating relative position information of the two modules, alignment portions provided in the two modules are engaged with each other by calibrating operation of at least one of the two modules. [Selection drawing] Fig. 1

Description

The present invention relates to a modular robot in which functional parts are modularized (replaceable structural units).

2. Description of the Related Art Conventionally, a robot with a modular structure, in which functional parts are modularized so that the functional parts can be easily attached and detached, is disclosed, for example, in Patent Document 1.

The modular construction robot includes a worm-driven drive module, an arm joint extending perpendicular to the axis of the drive module, and coaxially positioned with the drive module to transmit torque from the drive module to the arm joint. An articulated robot is configured by combining a plurality of connection modules, including one drive module corresponding to the trunk attached to the base, and the plurality of drive modules are shared for easy assembly. A plurality of connection modules also have common specifications.

Japanese Patent Publication No. 2017-508635

However, even with the above-described modular robot, if the production line stops due to a failure or maintenance, the production line must be stopped until repairs and maintenance are completed and the robot can be restarted, and related equipment often stops. In the event of a failure, the robot is replaced or repaired, but in the case of robot replacement, re-teaching is required, and in the case of robot repair, it is necessary to investigate the cause, restore, and verify operation. time-consuming.

Moreover, when the robot is replaced, there is a large deviation in the teaching position due to individual differences in the installation location and the robot, and it takes time to teach to restore the operation after the robot is replaced. Location information calibration work is required.

Even if you try to replace the robot module by module, it is necessary to perform a very time-consuming work such as hand position calibration after module removal. Also, in order to separate it, it takes time and effort to remove the cover and the wiring inside the trunk in order to remove the electrical connector.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a modular robot capable of easily attaching and detaching each module and calibrating the position information thereafter.

In order to advantageously solve the above problems, the present invention provides a modular robot comprising a plurality of modules each constituting a functional part,
two modules adjacent to each other among the plurality of modules are detachably coupled to each other while being roughly positioned by fitting portions provided in the modules;
In order to calibrate the relative positional information of the two modules after they are combined , the alignment parts respectively provided in the two modules are engaged with each other by calibrating operation of at least one of the two modules. there is

According to the modular structure robot of the present invention, two modules adjacent to each other among a plurality of modules (replaceable structural units) each constituting a functional part are roughly positioned by fitting portions provided on the modules. Since the two modules are detachably connected to each other in a state of being connected to each other, the two modules can be easily detached from each other. The alignment features provided on each of the two modules are engaged with each other by the calibrating operation of at least one of the two modules, so that the two modules can be operated with high accuracy relative to each other.

In the modular structure robot of the present invention, the two modules adjacent to each other are a trunk module that constitutes the trunk erected on the base as the functional portion, and a trunk module that constitutes the trunk as the functional portion. It may be an arm module that constitutes an arm attached to the part.

With this configuration, the arm modules, which constitute the arms attached to the sides of the trunk, are provided to the trunk modules, which constitute the trunk, standing on the base. Since the arm modules are detachably connected to each other in a roughly positioned state by the fitted fitting portions, the arm module can be easily attached to and detached from the trunk module. In order to calibrate the relative position information of the arm module with respect to the trunk module, alignment units respectively provided in the trunk module and the arm module are aligned with each other by calibrating at least one of the trunk module and the arm module. Since they are engaged, the arm module can be moved with high precision relative to the trunk module.

Further, the modular structure robot of the present invention comprises two arm modules constituting arms attached to the left and right sides of the trunk,
The alignment feature provided on the trunk module may engage either of the alignment features provided on the two arm modules.

In this way, the relative positional information of the two arm modules with respect to the trunk module can be calibrated by a single positioning unit on the trunk module side. It is also possible to calibrate the relative position information between them.

In the modular structure robot of the present invention, the two modules adjacent to each other are a trunk module that constitutes a trunk erected on the base as the functional portion, and an upper end of the trunk as the functional portion. It may be a head module that configures the head attached to the part and is arranged so that the position information of the target object can be acquired by using two cameras as stereo vision.

In this way, the head module constituting the head attached to the upper end of the trunk is provided in the trunk module constituting the trunk erected on the base. The head module can be easily attached to and detached from the body trunk module, and the body modules can be easily attached and detached after the modules are attached. For calibrating the relative position information of the head module with respect to the trunk module, alignment units respectively provided in the trunk module and the head module are engaged with each other by a calibration operation of at least one of the trunk module and the head module. Since they are combined, the head module can be operated with high accuracy with respect to the trunk module. Then, two cameras of the head module whose relative position to the trunk module is calibrated and arranged so that the position information of the target can be acquired as stereo vision capture the target. By obtaining the positional information of the object from the captured two-dimensional image by, for example, three-dimensional imaging processing or the principle of triangulation, the relative position of the object with respect to the trunk module can also be obtained with high accuracy.

1 is a partially cutaway perspective view of a modular robot according to an embodiment of the present invention with modules separated from each other; FIG. FIG. 3 is a perspective view showing the modular structure robot of the above embodiment in a state where modules are coupled together; FIG. 11 is a front view showing calibration operation of the arm module of the modular structure robot of the embodiment; (a) is a side view showing an alignment part provided in an arm module of the modular robot, and (b) is an alignment part provided in the trunk module and the arm module of the modular robot. FIG. 4 is a cross-sectional view showing an engaged state of parts; (a) is a front view showing the calibrating operation of the head module of the modular structure robot of the above-described embodiment, and (b) is an alignment unit provided in each of the trunk module and the head module of the modular structure robot. is a cross-sectional view showing the engaged state of.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. Here, FIG. 1 is a partially cutaway perspective view showing a modular robot according to an embodiment of the present invention with the modules separated, and FIG. It is a perspective view shown in a state.

The modular structure robot of this embodiment constitutes a dual-arm upper-body robot that can be used as an industrial robot or a service robot. As shown in FIGS. A trunk 2 erected, two articulated arms 3 attached to the left and right sides of the trunk 2, and a head 4 attached to the upper end of the trunk 2. I have.

The base 1 has an annular flange 1a at its upper end to which the trunk 2 is attached, and has a normal motor-type drive mechanism for horizontally rotating the trunk 2 about its central axis via the flange 1a. It has a lumbar joint portion inside, and is fixedly supported on a carriage (not shown) that can be moved manually or by itself, for example. The carriage is equipped with a normal control computer for operating the modular robot of this embodiment based on a work program given in advance.

The trunk 2 has a cylindrical frame 2a with a lower end attached to an annular flange 1a of the base 1, and is provided on the upper part of the frame 2a and has joints of the arms 3 and the head 4 inside. U-shaped brackets 2c for mounting the arms 3 are provided on the left and right sides of the frame 2a. , and an annular flange 2d to which the head 4 is attached is fixed to the upper end of the frame 2a with the mounting surface of the head 4 facing upward.

The two arms 3 basically have the same structure except that they are bilaterally symmetrical. That is, each arm portion 3 has an upper arm portion 3a, a forearm portion 3b, and a wrist portion 3c. A two-degree-of-freedom shoulder joint 3d for swinging the upper arm 3a in the horizontal direction about the vertical axis and in the vertical direction about the horizontal axis, and the forearm 3b moving vertically about the horizontal axis with respect to the upper arm 3a. Elbow joint 3e with one degree of freedom for swinging in any direction, and wrist 3c with respect to forearm 3b is rotated around a twist axis in the extending direction, a bending axis orthogonal thereto, and a rotation axis orthogonal to them. and a wrist joint portion 3f with 3 degrees of freedom that allows That is, the arm module (shown with the same reference numeral 3 as the original part for easy understanding) consisting of the arm 3 has a total of 6 degrees of freedom. The shoulder joint 3d, elbow joint 3e and wrist joint 3f each have a conventional motorized drive mechanism.

The head 4 has two cameras 4a, for example, video cameras arranged in the front part so as to be able to acquire the positional information of the object as stereo vision, and two-dimensional images captured by those cameras 4a. The control computer calculates the distance from the imaging subject to the head 4 and the imaging by, for example, three-dimensional imaging processing in which a large number of images are superimposed as tomograms in the perpendicular direction, and the application of the principle of triangulation to the three-dimensional images. The direction of the object can be calculated as the positional information of the object to be photographed. The head 4 has two cameras 4a attached to a flange 2d at the upper end of the frame 2a, and the two cameras 4a are attached to the flange 2d in the left-right direction around the vertical axis and in the up-down direction around the roughly horizontal axis. It has a two-degree-of-freedom neck joint 4b with a normal motor-type drive mechanism for swinging the neck joint 4b.

According to the modular structure robot of this embodiment, each joint is operated based on a work program given in advance to the control computer in the carriage, and an end effector such as a hand (not shown) attached to the wrist 3c is used to For example, it is possible to perform operations such as assembling and inspecting the packaging box, storing the product in the packaging box, and carrying out the packaging box containing the product.

In the modular robot of this embodiment, the base 1 and the trunk 2 are detachable modules (exchangeable structural units), and the arms 3 and the head 4 are attached to the trunk 2, respectively. are detachable modules (exchangeable structural units) to form a modular structure. 2) is fixed to the lower end of the frame 2a with an annular flange 2e corresponding to the flange 1a of the base module consisting of the base 1 (indicated by the same reference numeral 1 as the original part for ease of understanding). , the flange 1a of the base module 1 and the flange 2e of the trunk module 2 are respectively formed with a bolt hole and a pin hole facing each other. are provided upright, and female threads are formed in four bolt holes 1c that sandwich the pin holes 1b in the circumferential direction. The flange 2e is sized so that it can be fitted with a slight play within the tolerance range, and the remaining four pin holes of the flange 2e are sized so that the fixing bolts 6 screwed into the female threads of the bolt holes 1c can be inserted. formed.

A head module (shown with the same reference numeral 4 as the original part for ease of understanding) consisting of a head 4 is also provided at the lower end of the neck joint portion 4b as in the case of the trunk module 2. An annular flange 4c corresponding to the flange 2d of the module 2 is fixed, and the flange 2d of the trunk module 2 and the flange 4c of the head module 4 are formed with bolt holes and pin holes facing each other. Positioning pins 5 are erected in two pin holes spaced apart from each other in the diametrical direction of 2d, female threads are formed in four bolt holes sandwiching those pin holes in the circumferential direction, and two pin holes in the flange 2d The two pin holes of the flange 4c facing each other are sized so that the positioning pin 5 can be fitted with a slight play within the tolerance range, and the remaining four pin holes of the flange 4c are bolt holes of the flange 2d. It is formed in a size that allows a fixing bolt 6 to be screwed with the internal thread of.

The arm module 3 is fixed with a U-shaped bracket 3g corresponding to the bracket 2c of the trunk module 2 on the side surface of the shoulder joint 3d facing the side of the trunk module 2. The flange 2c and the bracket 3g of the arm module 3 are respectively formed with a bolt hole and a pin hole facing each other. The two pin holes of bracket 3g facing the two pin holes of bracket 2c allow the positioning pin 5 to have a slight play within the tolerance range. The remaining four pin holes of the bracket 3g are sized to allow insertion of fixing bolts (not shown) that screw into the female threads of the bolt holes of the bracket 2c.

Here, as shown in FIG. 2, wiring 8 for electrically connecting between the trunk module 2 and the arm module 3 and between the trunk module 2 and the head module 4, and wiring 8 between the trunk module 2 and the head module 4 Pipes such as hoses for supplying air pressure between the arm module 3 and between the trunk module 2 and the head module 4 are exposed to the outside. The connectors for relaying the supply of air pressure by piping are all fixedly arranged on the trunk module 2 side and inside the front side cover 2f and the rear side cover 2g which can be easily attached to and detached from the trunk section 2b of the trunk module 2. , and exposed to the outside by removing the front side cover 2f and the rear side cover 2g. The brackets 2c on the left and right sides of the frame 2a of the trunk 2 are also housed inside the front cover 2f and the rear cover 2g when viewed from the front-rear direction and above the trunk module 2, and the front cover 2f. By removing the rear side cover 2g, the fixing bolts 6 and the like of the arm module 3 are detachably exposed to the outside. Furthermore, the flange 2d at the upper end of the frame 2a of the trunk 2 is also housed inside the front cover 2f and the back cover 2g when viewed from the front-rear direction of the trunk module 2. By removing the cover 2g, the fixing bolts 6 and the like of the head module 4 are detachably exposed to the outside. As a result, the cover that needs to be removed when attaching and detaching the arm module 3 and the head module 4 is only on the side of the trunk module 2, so that the attachment and detachment of each module can be easily performed. In addition, there is no need to store unused wiring in the cover when changing to a different configuration, such as the presence or absence of wiring for optional equipment attached to the arm module 3 and the head module 4, or the presence or absence of mounting of the module itself. Therefore, the configuration can be easily changed.

As another embodiment of the present invention, the flange 1a of the base module 1 and the corresponding flange 2e of the trunk module 2 are also provided with the flange 2d of the trunk module 2 and the corresponding flange 4c of the head module 4. each has a hole in the center, and the bracket 2c of the trunk module 2 and the corresponding bracket 3g of the arm module 3 each have a notch extending to the center. (2) wires and connectors for electrically connecting between the base module 1 and the trunk module 2 and between the trunk module 2 and the arm module 3 and the head module 4; the base module 1 and the trunk module; Pipes such as hoses for supplying air pressure and connectors for these pipes may be arranged between the module 2 and between the trunk module 2 and the arm module 3 and head module 4 . By arranging the electrical wiring that connects the modules, the connectors for the wiring, the piping that supplies the pneumatic pressure, and the connectors for the piping in these holes and notches, the electrical wiring between the modules can be Wiring and pneumatic lines can be easily disconnected and reconnected in a short amount of time.

Furthermore, in the modular structure robot of this embodiment, when the front side cover 2f of the trunk portion 2b of the trunk module 2 is removed, the support plate 7 is placed forward on the front trunk portion 2b of the trunk module 2, The support plate 7 has both sides fixed to the left and right brackets 2c of the trunk module 2, and a disk-shaped calibration point 7a for calibrating the operating position of the wrist 3c of the arm module 3 protruding from the center. Further, a pin hole 7b is formed at a predetermined position near the calibration point 7a. The calibration points 7a and pin holes 7b are housed inside a front cover 2f that can be easily attached to and detached from the body 2b of the trunk module 2, and are exposed to the outside by removing the front cover 2f. .

According to the modular structure robot of this embodiment, as shown in FIG. are detachably connected by bolts 6 in a state where they are roughly positioned within the tolerance range by fitting portions consisting of pins 5 and pin holes provided in these modules, so that the trunk module 2 can be attached to the base. The module 1 can be easily attached/detached, and the arm module 3 and the head module 4 can be easily attached/detached to/from the trunk module 2 .

FIG. 3 is a front view showing the calibration operation of the arm module of the modular structure robot of the above embodiment, and FIG. FIG. 4(b) is a cross-sectional view showing the engagement state of the positioning portions provided in the trunk module and the arm module of the modular robot. After connecting the arm modules 3, as shown in FIGS. 3 and 4(b), each arm module 3 is calibrated with respect to the trunk module 2. A concave portion 3i having a corresponding shape of a wrist portion 3c as an alignment portion provided on the arm module 3 is fitted to the disk-shaped calibration point 7a by aligning the position and posture of the wrist portion 3c. The protruding pin 3h is oriented around the axis with respect to the calibration point 7a and fitted into the pin hole 7b near the calibration point 7a of the support plate 7. In this state, the trunk module 2 and the arm section are fitted. Relative position information with the module 3 is calibrated.

That is, by fitting the concave portion 3i and the pin 3h of the wrist portion 3c into the calibration point 7a and the pin hole 7b, respectively, and fixing the position and orientation of the wrist portion 3c, six degrees of freedom (six axes) are obtained as described above. The degree of freedom of the arm module 3 becomes non-redundant, and the angle of each joint axis provided in the arm module 3 is uniquely determined. However, since the arm module 3 has elastic characteristics (for example, distortion due to stress generated in the speed reducer), each joint axis of the arm module 3 is subjected to a predetermined drive torque by the motor of the joint axis during calibration. The addition eliminates the effect of the elastic properties of the arm module 3 on the calibration results.

Therefore, according to the modular structure robot of this embodiment, the left and right arm modules 3 can be operated with high accuracy with respect to the trunk module 2, and the calibration points 7a and the pin holes 7b are aligned with the left and right arm modules. 3 are common, the left and right arm modules 3 can also be operated with high accuracy. Although FIG. 1 omits the exposed wires and connectors that electrically connect the left and right arm modules 3 to the trunk module 2, the wires and connectors are as described above. It may be arranged in a notch extending to the center of each of the bracket 2c of the trunk module 2 and the corresponding bracket 3g of the arm module 3. In this way, when the arm module 3 is attached and detached, The wiring can also be easily detached.

FIG. 5(a) is a front view showing the calibrating operation of the head module of the modular robot of the above embodiment, and FIG. 3 and 5(a), (b), the modular structure robot of this embodiment further includes a neck joint portion of the head module 4. FIG. The proximal end of an I-shaped calibration jig 7c as an alignment portion is attached to the front surface of the body 4b, and the tip of the calibration jig 7c is attached to the front near the upper end of the frame 2a of the trunk module 2. A short piece-shaped calibration point 7d is projected forward as a fitting alignment portion.

In the modular structure robot of this embodiment, as shown in FIGS. The concave portion at the center of the tip of the tool 7c is fitted into the calibration point 7d as an alignment portion provided on the trunk module 2 by performing a calibration operation in which the head module 4 faces directly downward with respect to the trunk module 2. In this state, the relative positional information of the trunk module 2 and the head module 4 is calibrated for two degrees of freedom (two axes) of left-right rotation and up-down rotation of the head.

Therefore, according to the modular structure robot of this embodiment, the trunk module 2 can be easily attached to and detached from the base module 1, and the arm module 3 and the head module 4 can be easily attached to the trunk module 2. Moreover, the head module 4 as well as the arm module 3 can be operated with high precision with respect to the trunk module 2 .

Although the description has been made above based on the illustrated examples, the modular structure robot of the present invention is not limited to the above examples, and can be modified as appropriate within the scope of the claims. Also between the trunk module 2, a stopper erected on the base module 1 and a contact portion horizontally protruding from the lower end of the trunk module 2 are brought into contact with each other by the rotation of the trunk module 2. In this state, the relative rotation position of the trunk module 2 with respect to the base module 1 may be calibrated.

In the present invention, each module may have a different configuration depending on the purpose of use of the robot, and may be replaced and mounted as appropriate. It may be changed as appropriate depending on the purpose of use.

Thus, according to the modular structure robot of the present invention, two modules adjacent to each other among a plurality of modules (replaceable structural units) each constituting a functional part are roughly positioned by the fitting portions provided on the modules. Since the two modules are detachably connected to each other in the connected state, the two modules can be easily detached from each other. The two modules can be operated with high accuracy relative to each other, since the alignment features provided on each of the two modules are engaged with each other by the calibrating operation of at least one of the two modules.

Therefore, according to the modular structure robot of the present invention, the labor for re-teaching the motion of the robot after module replacement can be saved, so that the following effects can be obtained.
1) By replacing each module during maintenance, such as repairing or inspecting a faulty part of a robot placed on a production line, the downtime of the production line can be minimized.
2) Since the user of the robot can replace the module and calibrate the position, the maintenance man of the robot manufacturer does not have to make a business trip, and the maintenance man can provide efficient service.
3) By matching the specifications of the mounting part of the module and the specifications of the connection connector such as wiring between modules, it is possible to update each module, and it is possible to easily add, improve, and change the function of the robot.
4) Depending on the production status of the production line, the module configuration of the robot placed there can be changed between the minimum configuration and the maximum configuration. A robot that is optimal in terms of cost and operation can be realized by changing the configuration to an appropriate one for the work, such as by providing a camera for photographing the work object on the arm module.

1 base module (base)
1a flange 1b pin hole 1c bolt hole 2 trunk module (trunk)
2a frame 2b trunk 2c bracket 2d flange 2e flange 2f front side cover 2g rear side cover 3 arm module (arm)
3a upper arm 3b forearm 3c wrist 3d shoulder joint 3e elbow joint 3f wrist joint 3g bracket 3h pin 3i recess 4 head module (head)
4a camera 4b neck joint 4c flange 5 positioning pin 6 fixing bolt 7 support plate 7a calibration point 7b pin hole 7c calibration jig 7d calibration point 8 wiring

Claims (8)

In a modular structure robot comprising a plurality of modules each constituting a functional part,
two modules adjacent to each other among the plurality of modules are detachably coupled to each other while being roughly positioned by fitting portions provided in the modules;
In order to calibrate the relative positional information of the two modules after they are combined , the alignment parts respectively provided in the two modules are engaged with each other by calibrating operation of at least one of the two modules. modular structure robot. The two modules adjacent to each other include, as the functional portion, a trunk module that constitutes a trunk erected on the base, and an arm that constitutes an arm attached to the side of the trunk as the functional portion. The modular construction robot according to claim 1, characterized in that it is a partial module. comprising two arm modules constituting arms attached to the left and right sides of the trunk,
3. The modular structure robot according to claim 2, wherein the alignment portion provided on the trunk module engages with any of the alignment portions provided on the two arm modules. . Brackets for attaching the arm module to the trunk module are provided on the left and right sides of the trunk module,
4. The modular structure robot according to claim 3, wherein the bracket is housed inside a cover that can be easily attached to and detached from the body of the trunk module, and is exposed to the outside by removing the cover. . The trunk module is provided with a calibration point having a shape corresponding to the shape of the wrist as an alignment part of the arm module,
The calibration point is provided with a positioning pin capable of uniquely fixing the position and orientation of the wrist when fitting the wrist,
By applying a predetermined driving torque to each joint axis of the arm module in a state where the wrist is fitted to the calibration point with the position and orientation adjusted, the elasticity of the arm module to the calibration result is adjusted. 5. Modular construction robot according to any one of claims 2 to 4, characterized in that the influence of properties is excluded. A connector for relaying electrical connection and a connector for relaying air pressure supply between the trunk module and the arm module are fixedly arranged on the trunk module side and easily attached to the trunk of the trunk module. 6. The modular structure robot according to any one of claims 2 to 5, wherein the robot is housed inside a cover that is detachable from the body, and is exposed to the outside when the cover is removed. The two modules adjacent to each other constitute a trunk module that constitutes a trunk erected on the base as the functional portion, and a head that is attached to the upper end of the trunk as the functional portion. 7. The modular structure robot according to any one of claims 1 to 6, characterized in that the head module is arranged so as to be able to obtain the position information of an object using two cameras as stereo vision. A connector for relaying electrical connection and a connector for relaying air pressure supply between the trunk module and the head module are fixedly arranged on the trunk module side and easily attached to the trunk of the trunk module. 8. The modular structure robot according to claim 7, which is housed inside a cover that can be attached to and removed from the housing, and is exposed to the outside when the cover is removed.

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