DE102019128605B4 - robotic system - Google Patents

Abstract

A robot system (1) comprising: a robot body (2); anda controller (3) that controls the robot body (2),wherein the robot body (2) rotates about a first axis (L4) with a first wrist member (26) supported at a distal end of an arm (24), extending along the longitudinal axis of the arm (24) to be rotatable, a second wrist member (27) supported on the first wrist member (26) to be rotatable about a second axis (L5) which is the first axis (L4) intersects to be rotatable and a third wrist member (28) supported on the second wrist member (27) to be rotatable about a third axis (L6) intersecting the second axis (L5); a wire body (5) wired through the inside of the arm (24) connected to a working organ (4) fixed to the third wrist member (28) so as to pass through a wire body outlet provided in the first wrist member (26). an air path outside the robot body (2) goes through andthe control device (3) is provided with: an angle calculation unit (32) which calculates an angle (Aθ, Bθ) a straight line (LA, LB) connecting the wire body outlet and a specific point (A, B) of the wire body (5), the straight line (LA, LB) being projected onto a plane perpendicular to the coordinate axis, calculated around the coordinate axis with respect to a position where a load acting on the wire body (5) is smallest; and a determination unit (33) which determines whether the absolute value of the angle (Ae, Be) calculated by the angle calculation unit (35) has exceeded a predetermined angle threshold value.

Description

The present invention relates to a robot system.

In the prior art, there is known an industrial robot in which part of a wire body wired through the inside of the robot is led to the outside of a wrist and connected to a tool attached to the distal end of the wrist, thereby allowing a sufficient extra length of the wire body in an exterior of the wrist, and the sufficient extra length of the wire body absorbs bending and twisting of the wire body caused by the operation of the wrist, thereby reducing damage to the wire body (e.g., PTL 1).

[PTL 1] Japanese Unexamined Patent Application Publication No.: JP 2003 - 305 683 A

However, in the industrial robot of PTL 1, there is a disadvantage that the wire body is twisted too much depending on an operating angle of the wrist and considerable damage is unknowingly caused to the wire body, thereby reducing the life of the wire body at an early stage.

From the pamphlet DE 60 2005 005 752 T2 a laser processing robot with a manipulator is also known. The robot includes a laser processing tool attached to the manipulator, an optical fiber for transmitting a laser beam to the laser processing tool, and a conduit passage formed inside an arm portion to receive the optical fiber. The arm portion includes a first member fixed about a first control axis and a second member supported on the first member for rotation about the first control axis. The duct is continuous within the first and second members, with an optical fiber inlet port provided in the first member and an optical fiber outlet port provided in the wrist portion. The laser processing tool includes an attachment portion rotatably attached to the wrist part about a second control axis perpendicular to the first control axis; a nozzle portion extending from the attachment portion and provided with a laser beam passage extending to intersect the second control axis; and a reflecting portion disposed inside the fixing portion for reflecting a laser beam emitted from the optical fiber and directing it to the laser beam passage. The emitting end face of the optical fiber is located between the optical fiber outlet port and the reflecting portion.

The pamphlet EP 2 006 056 B1 discloses an industrial robot having an arm, a wrist member rotatably connected to the arm, a work tool attached to a distal end of the wrist member, and a motor attached to the wrist member; wherein an umbilical member connected to the working tool and a flat cable connected to the motor are arranged to run along the wrist member from the arm side to the auxiliary working tool or the motor. A tubular member inside the arm extending in the direction of a rotation axis of the wrist member is provided to guide the umbilical member connected to the working tool inside the tubular member, wherein the flat cable connected to the motor is wound around the outside of the tubular member, the flat cable being rotated in a direction of rotation of the Wrist element sagging.

The pamphlet EP 1 602 460 A1 discloses a system for managing supply lines for an industrial robot. The system is provided with a manipulator comprising a forearm having a first longitudinal axis, the forearm comprising a base and a first wrist member rotatably connected to the base about the first axis and a second wrist member rotatable with the first wrist member connected about a second axis generally perpendicular to the first axis; a work tool attached to the second wrist member of the forearm of the manipulator. An umbilical member routed outside the forearm between the base and the second wrist member is connected to the work tool. A guide portion for the umbilical member provided in the forearm includes a guide passage extending generally parallel to the first axis for receiving the umbilical member in a guideable manner. A holding portion is provided for the umbilical member, which is provided in the second wrist member to hold the umbilical member in a proper position relative to the working implement.

The umbilicus guide portion is configured to follow rotation of the first wrist member about the first axis and translate about the first axis. The umbilical member holding portion is configured to follow rotational movement of the second wrist member about the second axis and bend the umbilicus at a radius that is not smaller than an allowable bending radius between the umbilicus guide portion and the second wrist member.

The pamphlet U.S. 2011/0 252 915 A1 discloses a robot in which a flow path for supplying driving gas to a tool mounting portion is arranged from a robot base to the tool mounting portion through the inside of a rotary frame, a pipe, a shoulder, a swing arm and a tool mounting rotary arm.

The pamphlet U.S. 7,202,442 B2 discloses a cable assembly for a robotic arm that includes a rotating arm and a conduit member such as a power cord. The rotary arm has a front end and a base end, the front end being provided with a pivot shaft and the base end being provided with a rotary shaft rotatable about a longitudinal axis. The duct extends from the base end to the front end of the arm. The rotating shaft includes a wire offset member formed with at least one through hole for passing the wire member therethrough. The through hole as a whole is offset from the axis of the rotating shaft.

The pamphlet U.S. 5,083,284 A discloses an apparatus for predicting cable life for moving parts of an industrial robot. The device comprises measuring devices connected to the cables for the moving parts of the industrial robot for measuring the mechanical movement of the cables for the moving parts and a CPU for collecting results obtained by the measuring devices and predetermined reference values to determine that the cables for the moving parts have exceeded their service life if the sum exceeds a predetermined reference value.

An object of the present invention is to provide a robot system that allows operation of a wrist within a range where no damage is caused to a wire body, that can stabilize the life of the wire body, and that can reduce the frequency of maintenance. This object is solved by a robot system with the features of claim 1. Advantageous configurations are the subject matter of the dependent claims.

According to one aspect, the present invention provides a robot system, comprising: a robot body; and a controller that controls the robot body, the robot body having a first wrist member supported at a distal end of an arm to be rotatable about a first axis extending along the longitudinal axis of the arm, a second wrist member, supported on the first wrist member to be rotatable about a second axis intersecting the first axis and a third wrist member supported on the second wrist member to be rotatable about a third axis intersecting the second axis to be provided; a wire body wired through the inside of the arm is connected to a working organ fixed to the third wrist member so as to pass from a wire body outlet provided in the first wrist member through an air path outside the robot body; and the control device is provided with: an angle calculation unit that is in a Cartesian coordinate system whose origin is the wire body outlet and which has a coordinate axis extending in a direction along the first axis, an angle of a straight line that includes the wire body outlet and a specific point of the wire body, wherein the straight line is projected on a plane perpendicular to the coordinate axis, calculated around the coordinate axis with respect to a position where a load acting on the wire body is smallest; and a determination unit that determines whether the absolute value of the angle calculated by the angle calculation unit has exceeded a predetermined angle threshold.

According to this aspect, the wire body wired through the inside of the arm is connected to the working organ fixed to the third wrist member so as to be discharged from the wire body outlet of the first wrist member fixed to the distal end of the arm of the robot body through an air path outside the robot body goes through. In this case, when the second wrist member is rotated about the second axis with respect to the first wrist member, or when the third wrist member is rotated about the third axis with respect to the second wrist member, the air path changes, thereby changing the amount of twist at the particular point of the wrist Wire body changes according to the size of the rotation angle.

According to this aspect, the angle calculation unit calculates an angle of the straight line connecting the specific point and the wire body outlet, the straight line projected on a plane perpendicular to the coordinate axis, about the coordinate axis with respect to a position where the load is is smallest, and the determining unit determines whether the absolute value of the calculated angle has exceeded the angle threshold. It's imaginable, that the calculated angle represents the amount of twist of the wire body at the position of the particular point, and if this angle is more than the angle threshold, severe twist damage is caused to the wire body. By changing an operation program or changing the control based on the determination result, it is possible to allow the wrist to be operated in a range where no damage is done to the wire body to stabilize the life of the wire body and reduce the frequency of maintenance .

In the aspect described above, the control device may be provided with a distance calculation unit that calculates the distance between the wire body outlet and the specified point of the wire body; and the determination unit may determine whether the distance calculated by the distance calculation unit has exceeded a predetermined distance threshold corresponding to the angle.

With this configuration, when the second wrist member is rotated about the second axis relative to the first wrist member or when the third wrist member is rotated about the third axis relative to the second wrist member, the air path changes, thereby changing the amount of pulling or the amount of squeezing at the specific point of the wire body changes according to the magnitude of the twist angle.

The distance calculation unit calculates the distance of the straight line connecting the specific point and the wire body outlet, and the determination unit determines whether the calculated distance has exceeded the distance threshold value corresponding to the angle. It is conceivable that the calculated distance represents the amount of pulling or the amount of squeezing of the wire body at the position of the specific point, and if this distance is more than the distance threshold, severe damage due to pulling or squeezing will be caused to the wire body . By changing the operation program or changing the control based on the determination result, it is possible to allow the wrist to be operated in a range where no damage is done to the wire body to stabilize the life of the wire body and reduce the frequency of maintenance .

In the aspect described above, the control device can control the robot body in an angle range in which the angle does not exceed the angle threshold.

With this configuration, it is possible to keep the robot body operating at angles of the respective wrist members at which less damage is caused to the wire body, to stabilize the life of the wire body and reduce the frequency of maintenance.

In the aspect described above, the control device may be provided with a notification unit that, when it is determined that the angle has exceeded the angle threshold value, issues a notification indicating the determination result.

With this configuration, it is possible to notify an operator that the damage done to the wire body is large and prompt correction of the operation program.

In the aspect described above, the control device can control the robot body within a distance range in which the distance does not exceed the distance threshold.

With this configuration, it is possible to keep the robot body operating at angles of the respective wrist members at which less damage is caused to the wire body, to stabilize the life of the wire body and reduce the frequency of maintenance.

In the aspect described above, the control device may be provided with a notification unit that, when it is determined that the distance has exceeded the distance threshold, issues a notification indicating the determination result.

With this configuration, it is possible to notify the operator that the damage done to the wire body is large and prompt correction of the operation program.

In the aspect described above, the control device may store the angles successively calculated by the angle calculation unit, and may calculate the life of the wire body based on the stored time-series angles.

With this configuration, with the life calculated, it is possible to more accurately represent the damage done to the wire body, and cause the operation program to be corrected based on the life.

• 1 ist eine Ansicht, die die Gesamtkonfiguration eines Robotersystems gemäß einer Ausführungsform der vorliegenden Erfindung zeigt.
• 2 ist ein Blockdiagramm zur Erläuterung einer Steuervorrichtung des in 1 gezeigten Robotersystems.
• 3 ist eine Ansicht zur Erläuterung der Bestimmung des Ausmaßes einer Beschädigung an einem speziellen Punkt A, die von einer Bestimmungseinheit der in 2 gezeigten Steuervorrichtung durchgeführt wird.
• 4 ist eine Ansicht zur Erläuterung der Bestimmung des Ausmaßes einer Beschädigung an einem speziellen Punkt B, die von der Bestimmungseinheit der in 2 gezeigten Steuervorrichtung durchgeführt wird.
• 5 ist ein Ablaufdiagramm zur Erläuterung des Betriebs des in 1 gezeigten Robotersystems.
• 6 ist ein Ablaufdiagramm zur Erläuterung einer Lebensdauerberechnungsroutine in dem in 5 gezeigten Ablaufdiagramm.

According to the present invention, an advantageous effect is offered in that it is possible to allow a wrist in a region where a wire body does not scratch added to stabilize the life of the wire body and to reduce the frequency of maintenance.

• 1 12 is a view showing the overall configuration of a robot system according to an embodiment of the present invention.
• 2 FIG. 14 is a block diagram for explaining a control device of FIG 1 shown robot system.
• 3 Fig. 13 is a view for explaining the determination of the extent of damage at a specific point A made by a determining unit of Figs 2 control device shown is carried out.
• 4 FIG. 14 is a view for explaining the determination of the extent of damage at a specific point B made by the determination unit of FIG 2 control device shown is carried out.
• 5 is a flow chart for explaining the operation of the in 1 shown robot system.
• 6 FIG. 14 is a flowchart for explaining a life calculation routine in FIG 5 shown flow chart.

A robot system 1 according to an embodiment of the present invention will be described below with reference to the drawings.

According to the illustration in 1 For example, the robot system 1 of this embodiment is provided with a robot body 2 and a controller 3 that controls the robot body 2. FIG.

The robot body 2 is, for example, a 6-axis articulated robot, and is provided with: a base 21 installed on a floor surface F; a rotary torso 22 supported to be rotatable about a first vertical axis L1 with respect to the base 21; a first arm 23 supported to be rotatable about a second horizontal axis L2 with respect to the rotary torso 22; a second arm (arm) 24 supported to be rotatable about a third horizontal axis L3 with respect to the first arm 23; and a 3-axis wrist unit 25 attached to a distal end of the second arm 24. As shown in FIG.

The 3-axis wrist unit 25 is provided with: a first wrist member 26 supported to be about a fourth axis (first axis) L4 extending in a direction along the longitudinal axis of the second arm 24 with respect to the second arm 24 to be rotatable; a second wrist member 27 supported to be rotatable about a fifth axis (second axis) L5 perpendicular to the fourth axis L4 with respect to the first wrist member 26; and a third wrist member 28 supported to rotate about a sixth axis (third axis) L6, which is perpendicular to the fifth axis L5 and which passes through the intersection of the fourth axis L4 and the fifth axis L5, with respect to the second wrist member 27 to be rotatable.

The second arm 24 and the first wrist member 26 have hollow structures with a hollow bore 26a about the fourth axis L4 extending along the fourth axis L4. The second wrist member 27 and the third wrist member 28 also have hollow structures having a hollow bore 27a and 28a, respectively, about the sixth axis L6 and extending along the sixth axis L6.

A laser processing tool (working body) 4 is fixed to the third wrist member 28, for example. A high-rigidity cable (not shown) or the like for driving the laser processing tool 4 passes through the hollow hole 26a in the second arm 24 and the first wrist member 26 from the rear of the second arm 24, passes through an air path from the outlet (wire body outlet) of the hollow bore 26a in the first wrist member 26 through the hollow bores 27a and 28a in the second wrist member 27 and the third wrist member 28 and is connected to the laser processing tool 4 . By wiring the cable with high rigidity along the fourth axis L4 and the sixth axis L6, excessive twisting and bending caused by rotation of the first wrist member 26, the second wrist member 27 and the third wrist member 28 is prevented from being applied to the cable.

On the other hand, a low-rigidity optical fiber cable (wire body) 5 guided to the outlet of the hollow bore 26a together with the cable or the like in the hollow bore 26a in the first wrist member 26 is routed through an air path different from that for the high-rigidity cable Stiffness differs, connected to the laser processing tool 4. Since the fiber optic cable 5 is not wired along the fourth axis L4 and the sixth axis L6, the fiber optic cable 5 is wired in a state where sufficient additional length to absorb rotation of the first wrist member 26, the second wrist member 27, and the twisting and bending caused by the third wrist member 28 is catered for.

However, in some cases, depending on the orientations of the wrist members 26, 27 and 28, excessive bending, pulling or squeezing acts at a specific point A located at a connecting part 41 of the optical fiber cable 5 for connection with the laser processing tool 4 or at a specific point B located at an intermediate position of the optical fiber cable 5 in the longitudinal direction. The specific points A and B can be set arbitrarily.

The control device 3 is provided with a processor and a memory and, as shown in FIG 1 an outlet coordinate system, which is a Cartesian coordinate system having the origin O at the center of the outlet of the hollow bore 26a in the first wrist member 26 and an X-axis (coordinate axis) extending in the direction along the fourth axis L4 extends, has.

Then, the controller 3 calculates the coordinates of each of the specific points A and B based on angle information on the respective wrist members 26, 27 and 28 of the robot body 2. The coordinates of the connecting part 41 on the laser processing tool 4 can be unique based on the angle information on the respective wrist members 26, 27 and 28 and the dimensions of the laser processing tool 4 can be calculated, and the coordinates of the intermediate position of the optical fiber cable 5 can be estimated based on the angle information on the respective wrist members 26, 27 and 28.

According to the illustration in 2 the control device 3 is provided with: a distance calculation unit 31 which assumes that there are straight lines LA and LB connecting the calculated coordinates of the specific points A and B and the origin O, and calculates the lengths (distances) A _R and B _R of the straight lines LA and LB are calculated; and an angle calculation unit 32 which calculates angles A _θ and B _θ of the straight lines LA and LB to the Z axis when the straight lines LA and LB are projected onto a YZ plane. In this embodiment, when the angles A _θ and B _θ to the Z-axis are 0°, the load on the optical fiber cable 5 is the smallest.

The control device 3 is provided with: a determination unit 33 which stores angle threshold values associated with the angles A _θ and B _θ and distance threshold values associated with the lengths A _R and B _R and which determines whether the calculated angles A _θ and B _θ and the calculated lengths A _R and B _R have exceeded the respective thresholds; and a lifetime calculation unit 34 which calculates the lifetime of the optical fiber cable 5. According to the illustration in 3 and 4 the angle thresholds and the distance thresholds for the respective positions of the specific points A and B are stored as ranges in which the coordinates of the distal ends of the straight lines LA and LB extending from the origin O can fall, and the angle thresholds and the distance thresholds can be expressed by polar coordinates using the lengths A _R and B _R of the straight lines LA and LB and the angles A _θ and B _θ from the coordinate axis.

A determination result from the determination unit 33 is displayed on a display unit (not shown) such as a display unit. B. a monitor displayed.

und $$\text{D}2=\text{Frb}\left({\text{B}}_{\text{R}}\right)+\text{F}\mathrm{\theta }\text{b}\left({\text{B}}_{\mathrm{\theta }}\right),$$

wobei
D1 das Ausmaß an Beschädigung an dem Verbindungsteil 41 an dem Glasfaserkabel 5 angibt,
D2 das Ausmaß an Beschädigung an der Zwischenposition des Glasfaserkabels 5 angibt,
A_R den Abstand von dem Ursprung O zu dem Verbindungsteil 41 an dem Glasfaserkabel 5 angibt,
A_θ den Winkel der geraden Linie LA, die zwischen dem Verbindungsteil 41 an dem Glasfaserkabel 5 und dem Ursprung O gezogen ist, zur Z-Achse in der YZ-Ebene angibt,
B_R den Abstand von dem Ursprung O zu der Zwischenposition des Glasfaserkabels 5 angibt,
B_θ den Winkel der geraden Linie LB, die zwischen der Zwischenposition des Glasfaserkabels 5 und dem Ursprung O gezogen ist, zur Z-Achse in der YZ-Ebene angibt,
Fra und Frb Funktionen zur Berechnung des Ausmaßes an Beschädigung auf Basis der Abstände A_R und B_R angeben, und
Fθa und Fθb Funktionen zur Berechnung des Ausmaßes an Beschädigung auf Basis der Winkel A_θ und B_θ angeben.The controller 3 calculates the amount of damage done to the optical fiber cable 5 at the specific points A and B based on the calculated lengths A _R and B _R and the calculated angles A _θ and B _θ of the straight lines LA and LB using the following equations; $$\text{D}1=\text{Mrs}\left({\text{A}}_{\text{R}}\right)+\text{f}\mathrm{\theta }\text{a}\left(\text{A}\mathrm{\theta }\right),$$

and $$\text{D}2=\text{color}\left({\text{B}}_{\text{R}}\right)+\text{f}\mathrm{\theta }\text{b}\left({\text{B}}_{\mathrm{\theta }}\right),$$

whereby
D1 indicates the extent of damage to the connector 41 on the fiber optic cable 5,
D2 indicates the extent of damage at the intermediate position of the fiber optic cable 5,
A _R indicates the distance from the origin O to the connection part 41 on the fiber optic cable 5,
A _{θ indicates} the angle of the straight line LA drawn between the connection part 41 on the optical fiber cable 5 and the origin O to the Z axis in the YZ plane,
B _R indicates the distance from the origin O to the intermediate position of the fiber optic cable 5,
B _θ indicates the angle of the straight line LB drawn between the intermediate position of the optical fiber cable 5 and the origin O to the Z axis in the YZ plane,
Fra and Frb provide functions for calculating the extent of damage based on the distances A _R and B _R , and
Fθa and Fθb specify functions for calculating the amount of damage based on the angles A _θ and B _θ .

[Formel 2] $$\text{L}=\text{H}-\text{D}$$

wobei
L die verbleibende Lebensdauer angibt,
H die Gesamtlebensdauer angibt,
D das Ausmaß an dem Glasfaserkabel während eines Zyklus zugefügte Beschädigung angibt, $${\text{D'}}_{\text{i}}=\text{D}1+\text{D}\mathrm{2,}$$

und
n die Anzahl an Abtastereignissen während eines Zyklus angibt.The control device 3 calculates the remaining life L of the optical fiber cable 5 with the life calculation unit 34 using the formulas (1) and (2) based on the calculated amounts of damage D1 and D1 D2 and shows the remaining lifetime L on the display unit.
[Formula 1] $$D={\displaystyle {\sum }_{i=0}^{n}D{\text{'}}_i}$$

[Formula 2] $$\text{L}=\text{H}-\text{D}$$

whereby
L indicates the remaining lifetime,
H indicates the total lifetime,
D indicates the amount of damage inflicted on the fiber optic cable during a cycle, $${\text{D'}}_{\text{i}}=\text{D}1+\text{D}\mathrm{2,}$$

and
n indicates the number of sampling events during one cycle.

The operation of the thus configured robot system 1 of this embodiment will be described below.

According to the robot system 1 of this embodiment, the control device 3 calculates as shown in FIG 5 and 6 , when the operation of the robot body 2 is started according to a tutorial taught in advance, the orientation S of the robot body 2 for T seconds later (step S1) and calculates the coordinates of the specific points A and B in the outlet coordinate system in the orientation S (step S2).

Next, based on the calculated coordinates, the distances A _R and B _R from the specific points A and B to the origin O of the outlet coordinate system are calculated, respectively (step S3). The angles A _θ and B _θ from the Z axis on the YZ plane in the outlet coordinate system are calculated, respectively (Step S4).

Next, the lifetime calculation unit 34 performs a lifetime calculation routine (step S5). In the lifetime calculation routine, the damage amount D' _i is calculated using the calculated distances A _R and B _R and the calculated angles A _θ and B _θ (step S51), and the calculated damage amount D' _i is stored (step S52 ). Then it is determined whether a cycle has been completed (step S53). If a cycle has not been completed, the flow chart returns to the main routine. When one cycle has been completed, the remaining life L is calculated (step S54) and displayed on the monitor (step S55), and the flowchart returns to the main routine.

Next, it is determined whether the calculated distances A _R and B _R and the calculated angles A _θ and B _θ have exceeded the respective threshold values (step S6). If the distances A _R and B _R and the angles A _θ and B _θ have not exceeded the respective threshold values, the steps are repeated from step S1. On the other hand, when it is determined in step S6 that the distances A _R and B _R and the angles A _θ and B _θ have exceeded the respective threshold values, this determination result is displayed on the display unit (step S7) and the operation of the robot body 2 is stopped ( step S8).

Thus, according to the robot system 1 of this embodiment, when the angles A _θ and B _θ calculated by the angle calculation unit 32 and the distances A _R and B _R have exceeded the respective threshold values, this determination result is displayed on the display unit with a notification being issued; thus, there is an advantage that by changing an operation program or changing control based on the determination result, it is possible to allow the 3-axis wrist unit 25 to operate in a range where no damage is caused to the optical fiber cable 5. to stabilize the life of the fiber optic cable 5 and reduce the frequency of maintenance. Since the angles A _θ and B _θ to be obtained T seconds later are predicted, a notification can be issued before the optical fiber cable 5 is damaged.

In particular, it is conceivable that the angles A _θ and B _θ represent the amounts of twisting of the optical fiber cable 5 at the positions of the specific points A and B, and the optical fiber cable 5 at the connection part 41 on the optical fiber cable 5 is subjected to serious damage due to twisting. Thus, by determining whether the angles A _θ and B _θ have exceeded the angle thresholds and issuing a notification depending on the determination result, it is possible to take action, e.g. B. to change the operation to such an operation that the optical fiber cable 5 is not damaged, thereby stabilizing the life of the optical fiber cable 5.

It is conceivable that the distances A _R and B _R represent pulling and squeezing of the fiber optic cable 5 at the positions of the specific points A and B, and the fiber optic cable 5 at the intermediate position of the fiber optic cable 5 is subjected to considerable damage due to pulling and squeezing. So it is by determining whether the distances A _R and B _R have exceeded the distance threshold values and issuing a notification depending on the determination result, it is possible to take measures, e.g. B. to change the operation to such an operation that the optical fiber cable 5 is not damaged, thereby stabilizing the life of the optical fiber cable 5.

According to this embodiment, since the remaining life L of the optical fiber cable 5 is calculated based on the calculated distances _{AR and B R and} angles A _θ and B _θ and displayed on the display unit, there is an advantage in that it is possible to display by the displayed objectively understand the damage done to the optical fiber cable 5 by the remaining lifetime L and cause correction of the operation program based on the remaining lifetime L .

In this embodiment, although based on both the lengths (distances) A _R and B _R of the straight lines LA and LB drawn from the origin O of the outlet coordinate system to the specific points A and B, and the angle A, it is _θ and B _θ of the straight lines LA and LB from the Z-coordinate axis with the straight lines LA and LB projected onto the YZ plane, whether the degree of damage D' _i of the optical fiber cable 5 is large is determined instead , to use only the angles A _θ and B _θ to determine damage arising specifically from twisting, or to use only distances AR and B _R to determine damage _arising specifically from pulling and compressing.

In this embodiment, as a result of the determination performed by the determination unit 33, notification of the determination result is issued when the distances A _R and B _R or the angles A _θ and B _θ have exceeded the threshold values; instead, however, the controller 3 may control the wrist members 26, 27 and 28 of the robot body 2 such that the distances A _R and B _R or the angles A _θ and B _θ do not exceed the threshold values when the distances A _R and B _R or the Angles A _θ and B _θ reach the thresholds.

In this embodiment, although means for performing screen display using the display unit as a notification unit is employed, it is also possible to employ means for issuing notification of a determination result by sound instead.

Although the optical fiber cable 5 is shown as an example of the wire body, the wire body is not limited to this.

In this embodiment, although the amount of damage D' _i using the functions Fra and Frb that calculate the amount of damage D' _i based on the distances A _R and B _R and the functions Fθa and Fθb that Calculating the damage amount D' _i based on the angles A _θ and B _θ is calculated, instead it is also possible to obtain the damage amount D' _i by consulting a database. Machine learning can also be applied.

reference list

1

robotic system

2

robot body

3

control device

4

Laser processing tool (working body)

5

fiber optic cable (wire body)

24

second arm (arm)

26

first wrist element

27

second wrist element

28

third wrist element

31

distance calculation unit

32

angle calculation unit

33

unit of determination

AWAY

special point

Aθ, Bθ

angle

AR, BR

length (distance)

L4

fourth axis (first axis)

L5

fifth axis (second axis)

L6

sixth axis (third axis)

LA, LB

straight line

Claims (7)

A robot system (1) comprising: a robot body (2); and a controller (3) that controls the robot body (2), the robot body (2) being supported about a first axis (L4) with a first wrist member (26) supported at a distal end of an arm (24) thereto. , which extends along the longitudinal axis of the arm (24) to be rotatable, a second wrist member (27) which the first wrist member (26) is supported to be rotatable about a second axis (L5) intersecting the first axis (L4), and a third wrist member (28) supported on the second wrist member (27) to be rotatable is provided to be rotatable about a third axis (L6) intersecting the second axis (L5); a wire body (5) wired through the inside of the arm (24) connected to a working organ (4) fixed to the third wrist member (28) so as to pass through a wire body outlet provided in the first wrist member (26). an air path outside the robot body (2) passes through; and the control device (3) is provided with: an angle calculation unit (32) which calculates an angle (A _θ , B _θ ) of a straight line (LA, LB) connecting the wire body outlet and a specific point (A, B) of the wire body (5), the straight line (LA, LB) on a plane perpendicular to the coordinate axis is projected calculated about the coordinate axis with respect to a position where a load acting on the wire body (5) is smallest; and a determination unit (33) which determines whether the absolute value of the angle (Ae, Be) calculated by the angle calculation unit (35) has exceeded a predetermined angle threshold value. Robot system (1) according to claim 1 wherein the control device (3) is provided with a distance calculation unit (31) which calculates the distance (A _R , B _R ) between the wire body outlet and the specific point (A, B) of the wire body (5); and the determination unit determines whether the distance (A _R , B _R ) calculated by the distance calculation unit (33) has exceeded a predetermined distance threshold value corresponding to the angle (A _θ , B _θ ). Robot system (1) according to claim 1 or 2 , wherein the control device (3) controls the robot body (2) in an angle range in which the angle (A _θ , B _θ ) does not exceed the angle threshold value. Robot system (1) according to claim 1 or 2 wherein the control device (3) is provided with a notification unit which, when it is determined that the angle (A _θ , B _θ ) has exceeded the angle threshold value, issues a notification indicating the determination result. Robot system (1) according to claim 2 , wherein the control device (3) controls the robot body (2) within a distance range in which the distance (A _R , B _R ) does not exceed the distance threshold value. Robot system (1) according to claim 2 wherein the control device (3) is provided with a notification unit which, when it is determined that the distance (A _R , B _R ) has exceeded the distance threshold value, issues a notification indicating the determination result. Robot system (1) according to claim 1 or 2 wherein the control device (3) stores the angles (Ae, Be) successively calculated by the angle calculation unit (32) and calculates the life of the wire body (5) based on the stored time-series angles.

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