JP2023170247A - Assistance power device and robot system - Google Patents

Abstract

To provide an assistance power device that can suppress assistance power from decreasing during conveying work, and a robot system.SOLUTION: An assistance power device comprises a base, a moving mechanism that moves the base in a horizontal direction, a locking part that locks an object, and a part to be connected which is connected to a robot, which further comprises a part to be operated that is operated by the robot and a force sensor that detects force applied to the part to be operated, a connecting part that connects the base to the part to be operated, and restricts the part to be operated from being displaced in a horizontal direction with respect to the base; a driving mechanism that moves the part to be operated up and down; and a control device that controls driving of the driving mechanism on the basis of force detected by the force sensor.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to an assistive device and a robot system.

For example, Patent Document 1 discloses a robot system (article moving device system) that includes an assisting device that assists a robot to transport an object with a weight greater than its carrying capacity. The assisting device also includes a locking member that locks the object, a link chain connected to the locking member, and a lifting operation unit that winds up or sends out the link chain to raise and lower the locking member. It has a motor as a drive source that drives the lifting and lowering operation section, and a weight detection section that outputs a weight value applied to the lifting and lowering operation section. Such an assisting device assists the robot in transporting the object by winding up the link chain in the lifting operation section and lifting the object. On the other hand, the robot holds the object via the locking member of the assist device and transports the held object to the destination. This allows the object to be transported even if the object weighs more than the robot's payload.

Japanese Patent Application Publication No. 2019-072804

However, in the robot system described in Patent Document 1, when the lifting actuator and the locking member shift in the horizontal direction, the link chain tilts with respect to the vertical direction due to the shift, and the link chain extends in the vertical direction. The assist force (the force that lifts the object upward in the vertical direction) decreases. Then, due to the decrease in the assist force, a weight greater than the weight that the robot can carry is added to the robot, which may impede the conveyance of the object or cause the robot to malfunction.

The assisting device of the present invention includes a base;
a moving mechanism that moves the base in a horizontal direction;
an operated part that is operated by the robot and includes a locking part that locks an object and a connected part that is connected to the robot;
a force sensor that detects a force applied to the operated part;
a connecting part that connects the base and the operated part and restricts horizontal displacement of the operated part with respect to the base;
a drive mechanism that raises and lowers the operated section;
and a control device that controls driving of the drive mechanism based on the force detected by the force sensor.

The robot system of the present invention includes a robot that performs a transport operation to transport a target object;
an assisting device that provides assistance to the robot;
The assisting device includes a base;
a moving mechanism that moves the base in a horizontal direction;
an operated part that is operated by the robot and includes a locking part that locks the object and a connected part that is connected to the robot;
a force sensor that detects a force applied to the operated part;
a connecting part that connects the base and the operated part and restricts horizontal displacement of the operated part with respect to the base;
a drive mechanism that raises and lowers the operated section;
and a control device that controls driving of the drive mechanism based on the force detected by the force sensor.

FIG. 1 is a diagram showing the overall configuration of a robot system according to a first embodiment. It is a figure which shows the state which raised the assistance device. It is a figure which shows the state which lowered the assistance device. It is a flowchart showing a work process performed using a robot system. It is a diagram showing a state in which a robot is connected to an assisting device. It is a figure which shows the state which latched the assistance device to the workpiece|work. FIG. 3 is a diagram showing a state in which the robot has lifted a workpiece. FIG. 6 is a diagram showing a state in which the robot has transported the workpiece to the destination. It is a figure which shows the problem that a striatum becomes oblique. FIG. 3 is a diagram showing a state in which a workpiece is placed at a destination. FIG. 3 is a diagram showing a state in which an assembly member is gripped by a robot. It is a figure showing the state where an assembly member is attached to a workpiece by a robot. FIG. 3 is a diagram showing the overall configuration of a robot system according to a second embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The assisting device and robot system of the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings.

<First embodiment>
FIG. 1 is a diagram showing the overall configuration of a robot system according to a first embodiment. FIG. 2 is a diagram showing a state in which the assist device is raised. FIG. 3 is a diagram showing a state in which the assist device is lowered. FIG. 4 is a flowchart showing the work steps performed using the robot system. FIG. 5 is a diagram showing a state in which the robot is connected to the assisting device. FIG. 6 is a diagram showing a state in which the assisting device is locked to a workpiece. FIG. 7 is a diagram showing a state in which the robot has lifted a workpiece. FIG. 8 is a diagram showing a state in which the robot has transported the workpiece to the destination. FIG. 9 is a diagram illustrating the problem of oblique striatal bodies. FIG. 10 is a diagram showing a state in which the workpiece is placed at the destination. FIG. 11 is a diagram showing a state in which the assembly member is gripped by the robot. FIG. 12 is a diagram showing a state in which an assembly member is attached to a work by a robot.

In each figure except FIG. 4, the vertical direction of the paper surface is the vertical direction, the upper side of the paper surface is the vertical upper side, and the lower side of the paper surface is the vertical lower side. Further, the lateral direction of the paper surface of each figure except FIG. 4 is the horizontal direction. Further, the term "vertical direction" in this specification includes not only a direction along the vertical direction but also a direction inclined with respect to the vertical direction to the extent that it can be regarded as the same as a direction along the vertical direction according to common technical knowledge. Furthermore, the term "horizontal direction" in this specification includes not only a direction along the horizontal direction but also a direction that is inclined with respect to the horizontal direction to the extent that it can be regarded as the same direction as a direction along the horizontal direction based on common technical knowledge.

A robot system 1 shown in FIG. 1 mainly performs a work of transporting a workpiece W as an object. The robot system 1 includes a robot 2, a robot control device 3 that controls the driving of the robot 2, and an assist device 4 that assists the driving of the robot.

<Robot 2>
The robot 2 is a six-axis robot having six drive axes. The robot 2 includes a base 21 fixed to a structure such as a floor, ceiling, wall, or frame, and a robot arm 22 rotatably connected to the base 21. Further, the robot arm 22 includes a first robot arm 221 rotatably connected to the base 21, a second robot arm 222 rotatably connected to the first robot arm 221, and a second robot arm 222 rotatably connected to the base 21. a third robot arm 223 rotatably connected to the second robot arm 222; a fourth robot arm 224 rotatably connected to the third robot arm 223; It has a fifth robot arm 225 that is movably coupled to the fifth robot arm 225 and a sixth robot arm 226 that is rotatably coupled to the fifth robot arm 225 .

Further, the end effector 23 is attached to the sixth robot arm 226 via the force sensor 24. Force sensor 24 detects the force applied to end effector 23. The configuration of the force sensor 24 is not particularly limited, but may include, for example, a configuration that has a pressure receiving body made of crystal and detects the force received based on the magnitude of the electric charge generated when the pressure receiving body receives the force. It can be done. Note that the arrangement of the force sensor 24 is not particularly limited as long as it can detect the force applied to the end effector 23. Further, the force sensor 24 may be omitted. Further, the end effector 23 is appropriately selected depending on the work to be performed by the robot 2. In this embodiment, a hand having a pair of claws that open and close is used as the end effector 23.

The robot 2 also includes a first drive mechanism 251 that rotates the first robot arm 221 with respect to the base 21 and a second drive mechanism 252 that rotates the second robot arm 222 with respect to the first robot arm 221. a third drive mechanism 253 that rotates the third robot arm 223 with respect to the second robot arm 222; and a fourth drive mechanism 254 that rotates the fourth robot arm 224 with respect to the third robot arm 223; It has a fifth drive mechanism 255 that rotates the fifth robot arm 225 with respect to the fourth robot arm 224 and a sixth drive mechanism 256 that rotates the sixth robot arm 226 with respect to the fifth robot arm 225. are doing.

These drive mechanisms 251, 252, 253, 254, 255, and 256 include, for example, a motor as a drive source, a reducer that decelerates and outputs the rotation of the motor, a controller that controls the drive of the motor, and a displacement amount ( It has an encoder etc. that detects the rotation angle).

<Robot control device 3>
The robot control device 3 independently controls the driving of each of the drive mechanisms 251 to 256 and the end effector 23 based on, for example, instructions from a host computer (not shown).

Such a robot control device 3 is composed of, for example, a computer, and includes a processor (CPU) for processing information, a memory communicably connected to the processor, and an external interface. Further, the memory stores various programs executable by the processor, and the processor can read and execute the various programs stored in the memory.

<Assistance device 4>
The assist device 4 is a device that provides assistance to the robot 2 by lifting and supporting the work W, and assists the robot 2 in transporting the work W. As shown in FIG. 1, such an assist device 4 includes a base 40, a moving mechanism 41 that supports the base 40 so as to be movable in the horizontal direction, and a robot 2 located below the base 40 and operated by the robot 2. An operated part 42, a force sensor 43 that detects the force applied to the operated part 42, a connecting part 44 that connects the base 40 and the operated part 42, a drive mechanism 45 that raises and lowers the operated part 42, It has a control device 46 that controls driving of the drive mechanism 45 based on the force detected by the force sensor 43.

The moving mechanism 41 includes a fixed part 410 fixed to a structure such as a floor, ceiling, wall, or frame, a first arm 411 rotatably connected to the fixed part 410, and a first arm 411 connected to the fixed part 410 so as to be rotatable. A second arm 412 is rotatably connected. The first arm 411 is connected to the fixing part 410 at its base end, and rotates about a first rotation axis Ja along the vertical direction with respect to the fixing part 410. The second arm 412 has its base end connected to the distal end of the first arm 411, and rotates around a second rotation axis Jb that is perpendicular to the first arm 411. The base 40 is arranged at the tip of the second arm 412. Therefore, when the first and second arms 411 and 412 rotate around the first and second rotation axes Ja and Jb, the base 40 moves in the horizontal direction. According to such a configuration, the configuration of the moving mechanism 41 becomes simple.

Note that the configuration of the moving mechanism 41 is not particularly limited as long as the base 40 can be moved in the horizontal direction. For example, the second arm 412 may also serve as the base 40. Further, the first arm 411 moves linearly in a first direction that is horizontal to the ceiling, etc., and the second arm 412 moves in a second direction that is horizontal to the first arm 411 and perpendicular to the first direction. It may also be configured to move linearly.

The operated part 42 includes an eye bolt 421 that is a screw with a ring, a base 422 to which the eye bolt 421 is fixed, a connected part 423 located below the base 422 and to which the robot 2 is connected, and a connected part 423 that is located below the base 422 and to which the robot 2 is connected. The damper device 424 is located under the section 423 and expands and contracts in the vertical direction, and the locking section 425 is located under the damper device 424 and locks the workpiece W.

The base 422 has a box shape and includes a bottom plate 422a, a top plate 422b located above the bottom plate 422a, and four columns 422c connecting the bottom plate 422a and the top plate 422b. ing. Further, a through hole is formed in the top plate 422b, and a filament body 453, which will be described later, is introduced into the base portion 422 through this through hole. Moreover, the eye bolt 421 is accommodated in the base 422 and fastened to the bottom plate 422a. A filament body 453 is connected to the ring of the eyebolt 421.

Further, the connected portion 423 is located below the base portion 422, and its upper end portion is connected to the bottom plate 422a. The connected portion 423 is a portion to which the end effector 23 of the robot 2 is connected. In this embodiment, the robot 2 and the end effector 23 are connected by the end effector 23 gripping the connected portion 423 . Therefore, the connected portion 423 is designed to have a shape that is easy for the end effector 23 to grip. Note that the method of connecting the connected portion 423 and the robot 2 is not particularly limited, and may be configured to connect by a method other than gripping, such as screwing, suction, etc.

Furthermore, the damper device 424 is located below the connected portion 423 . The damper device 424 includes a base portion 424a connected to the connected portion 423, a movable portion 424b located below the base portion 424a, and a plurality of dampers 424c connecting the base portion 424a and the movable portion 424b. ,have. Therefore, the damper device 424 expands and contracts by expanding and contracting the plurality of dampers 424c, and due to the expansion and contraction, the movable portion 424b is vertically displaced with respect to the base portion 424a.

The locking portion 425 is located below the damper device 424 and is connected to the movable portion 424b of the damper device 424. The locking portion 425 is a portion that locks the work W. The locking portion 425 of this embodiment has a hook 425a, and locks the workpiece W by hooking the workpiece W with the hook 425a. However, the configuration of the locking portion 425 is not particularly limited as long as it can lock the workpiece W. For example, the locking portion 425 may be configured to lock the workpiece W by gripping, suction, or the like.

Further, the connecting portion 44 connects the base 40 and the operated portion 42 and restricts displacement of the operated portion 42 relative to the base 40 in the horizontal direction. That is, the relative positional relationship between the base 40 and the operated part 42 in the horizontal direction is maintained by the connecting part 44. In particular, in this embodiment, the connecting portion 44 extends in the vertical direction, and the base 40 and the operated portion 42 are maintained in a vertically aligned state.

Further, the connecting portion 44 can expand and contract in the vertical direction. By expanding and contracting the connecting portion 44, the operated portion 42 is allowed to move up and down with respect to the base 40. That is, when the operated part 42 goes up, the connecting part 44 contracts, and when the operated part 42 goes down, the connecting part 44 expands. By making the connecting portion 44 expandable and retractable in this manner, the height (upper end position) of the connecting portion 44 can be kept constant regardless of whether the operated portion 42 is raised or lowered. Therefore, for example, compared to a configuration in which the connecting part 44 cannot expand and contract and moves up and down as the operated part 42 goes up and down, as in the second embodiment described later, the required amount is required to arrange the robot system 1. You can make the space smaller.

The connecting portion 44 includes a plurality of sliding members 440 that slide against each other in the vertical direction. This allows the connecting portion 44 to have a simple configuration. The connecting portion 44 includes, as a plurality of sliding members 440, a first sliding member 441, a second sliding member 442 that slides with respect to the first sliding member 441, and a second sliding member 442 that slides with respect to the second sliding member 442. It has a third sliding member 443 that slides.

The first sliding member 441 has a cylindrical shape extending in the vertical direction, and its upper end is connected to the base 40 . Further, the second sliding member 442 has a cylindrical shape extending in the vertical direction, and is inserted into the first sliding member 441. The second sliding member 442 can protrude downward from the first sliding member 441 or retreat into the first sliding member 441 by sliding in the vertical direction with respect to the first sliding member 441. do. Further, the third sliding member 443 has a cylindrical shape extending in the vertical direction, and its lower end portion is connected to the operated portion 42 . Further, the third sliding member 443 is inserted into the second sliding member 442. The third sliding member 443 can protrude downward from the second sliding member 442 or retreat into the second sliding member 442 by sliding in the vertical direction with respect to the second sliding member 442. do. According to such a configuration, the connecting portion 44 that can be expanded and contracted in the vertical direction can be realized with a simple structure.

Further, the second sliding member 442 is rotatable around the central axis O (an axis along the vertical direction) of the connecting portion 44 with respect to the first sliding member 441 . Further, the third sliding member 443 is rotatable around the central axis O with respect to the second sliding member 442. This allows the operated section 42 to rotate around the central axis O with respect to the base 40, allowing twisting between the operated section 42 and the base 40. Therefore, the degree of freedom in the direction of the operated part 42 is increased, and the conveyance work described below can be performed smoothly. In addition, external force (torque) around the central axis O is less likely to be applied to the assisting device 4, and breakdowns, damage, etc. of the assisting device 4 can be effectively suppressed.

Note that the configuration of the connecting portion 44 is not particularly limited as long as it can connect the base 40 and the operated portion 42 and restrict horizontal displacement of the operated portion 42 with respect to the base 40. For example, the number of sliding members 440 may be two, or four or more. Specifically, for example, the third sliding member 443 may be omitted, and the lower end portion of the second sliding member 442 may be connected to the operated portion 42. Furthermore, at least one sliding member 440 does not have to be cylindrical.

The drive mechanism 45 also includes a pulley 451 that is supported by the base 40 and rotates around a horizontal axis of rotation, a motor 452 that is supported by the second arm 412 and serves as a drive source that rotates the pulley 451, and a motor 452 that is supported by the second arm 412 and serves as a drive source that rotates the pulley 451. and the pulley 451, and a reducer 454 that decelerates the rotation of the motor and outputs it to the pulley 451; one end is connected to the pulley 451, and the other end is connected to the eye bolt 421 of the operated part 42. It has a striatum 453. The speed reducer 454 is not particularly limited, and for example, a strain wave gear speed reducer, an eccentric swing type speed reducer, or the like can be used.

In the drive mechanism 45 having such a configuration, as shown in FIG. 2, when the pulley 451 is rotated in the forward direction by the motor 452, the pulley 451 winds up the filament 453, and the operated part 42 is contracted while the connecting part 44 is contracted. Rise. On the other hand, as shown in FIG. 3, when the pulley 451 is reversely rotated by the motor 452, the pulley 451 sends out the filament 453, and the operated part 42 is lowered while the connecting part 44 is extended. According to such a configuration, the configuration of the drive mechanism 45 becomes simple. Further, excellent responsiveness can be exhibited, and the ability of the assisting device 4 to follow the movement of the robot 2 can be improved. Therefore, the transport work of the robot 2 can be effectively supported.

Note that the filament 453 is not particularly limited, and for example, a wire, rope, chain, or the like can be used. Furthermore, the filamentous body 453 hangs down from the pulley 451 in the vertical direction, passes through the connecting portion 44 , and is connected to the operated portion 42 . In this way, by inserting the filamentous body 453 into the connecting portion 44, the filamentous body 453 is not exposed, and the filamentous body 453 can be protected. However, the filamentous body 453 may pass outside the connecting portion 44 and be connected to the operated portion 42 .

The force sensor 43 detects the force applied to the operated portion 42 . The force sensor 43 of this embodiment is built in the motor 452 and includes a torque sensor that detects the load torque of the motor 452. However, the force sensor 43 is not particularly limited as long as it can detect the force applied to the operated part 42.

The control device 46 controls the drive of the drive mechanism 45 based on the force detected by the force sensor 43. Such a control device 46 is composed of a computer, for example, and includes a processor (CPU) that processes information, a memory communicably connected to the processor, and an external interface. Further, the memory stores various programs executable by the processor, and the processor can read and execute the various programs stored in the memory. Note that the robot control device 3 may also serve as the control device 46.

According to such an assisting device 4, when the robot 2 transports the workpiece W, by lifting the workpiece W, the load transmitted from the workpiece W to the robot 2 can be reduced, preferably zero. Thereby, the workpiece W can be smoothly transported by the robot 2. Furthermore, the robot 2 can transport a workpiece W that exceeds its payload (the weight that the robot 2 can transport). Therefore, it becomes possible to transport a heavier workpiece W using the robot 2 with a small payload capacity.

The configuration of the robot system 1 has been described above. Next, a working method using the robot system 1 will be explained. The robot control device 3 operates in an assisting work state in which the robot 2 is connected to the assisting device 4 and is being assisted by the assisting device 4, and in an assisting work state in which the robot 2 is not connected to the assisting device 4 and is being assisted by the assisting device 4. Switch between a non-help work state and a non-help work state in which work is performed without assistance, depending on the work content.

In the example shown below, as shown in FIG. 4, there is a transport work step S1 in which the robot 2 transports a work W exceeding the payload capacity, and a transport work step S1 in which the robot 2 performs an assembly work on the work W as a predetermined work. It includes an assembly work step S2. Hereinafter, each step S1 and S2 will be explained in detail with reference to FIG.

[Transportation work process S1]
In the transport work step S1, first, in step S101, the robot control device 3 moves the robot 2 to move the end effector 23 to the position where the operated part 42 of the assist device 4 is waiting. Next, as shown in FIG. 5, in step S102, the robot control device 3 moves the robot 2 to grip the connected portion 423 of the operated portion 42 with the end effector 23. Thereby, the robot 2 and the operated part 42 are in a connected state.

Next, the robot control device 3 moves the robot 2 to move the operated part 42 to the workpiece W supply position in step S103. At this time, the first and second arms 411 and 412 rotate around the first and second rotation axes Ja and Jb so as to follow the movement of the robot 2, thereby allowing the horizontal movement of the operated part 42. be done. Further, the control device 46 controls the drive of the motor 452 based on the force detected by the force sensor 43, and winds up/feeds out the filament 453 in accordance with the vertical movement of the robot 2. Preferably, the filament body 453 is wound up/feeded out so that the filament body 453 maintains a slightly bent state so that the robot 2 is not subjected to any load due to the tension of the filament body 453.

Next, as shown in FIG. 6, in step S104, the robot control device 3 moves the robot 2 to hook and lock the hook 425a of the operated portion 42 onto the workpiece W. Note that whether or not the hook 425a is engaged with the workpiece W can be determined based on the force detected by the force sensor 43, for example. Specifically, when the force detected by the force sensor 43 exceeds a predetermined threshold, it is determined that the hook 425a is engaged with the workpiece W, and when the force is below the threshold, the hook 425a is engaged with the workpiece W. It can be determined that it has not stopped. However, the method for determining whether the hook 425a is engaged with the workpiece W is not particularly limited.

Here, the feeding position of the workpiece W is taught to the robot control device 3 in advance, but depending on the accuracy of the teaching, the taught position may deviate from the actual feeding position of the workpiece W, or the workpiece may be moved to the feeding position. Depending on the W supply method, the actual supply position of the workpiece W may deviate from the taught position. Therefore, in this embodiment, a damper device 424 is disposed on the operated portion 42, and the damper device 424 expands and contracts, thereby allowing the above-mentioned deviation. Thereby, step S104 can be performed more reliably and smoothly. In addition, by expanding and contracting the damper device 424, the impact at the time of locking is alleviated and absorbed, and damage and failure of the workpiece W and the assisting device 4 can also be suppressed.

Next, as shown in FIG. 7, in step S105, the robot control device 3 moves the robot 2 to lift the workpiece W upward in the vertical direction. At this time, the control device 46 drives the motor 452 with an output corresponding to the weight of the workpiece W. In this embodiment, the load torque of the motor 452 detected by the force sensor 43 is fed back to the torque command value of the motor 452, and the torque Ft of the motor 452, the gravity Fm acting on the workpiece W, and the The drive of the motor 452 is controlled so that the sum of the gear resistances f becomes equal. That is, the driving of the motor 452 is controlled so that Ft=Fm+f. As a result, the force by which the assist device 4 lifts the workpiece W and the weight of the workpiece W cancel each other out, and the weight of the workpiece W applied to the robot 2 becomes substantially zero. Therefore, the robot 2 can easily lift the workpiece W. This control continues until the next step S106 is completed. However, as long as the weight of the workpiece W applied to the robot 2 is less than or equal to the payload of the robot 2, the present invention is not limited to this, and for example, Ft<Fm+f may be satisfied.

Next, as shown in FIG. 8, in step S106, the robot control device 3 moves the robot 2 to transport the workpiece W directly above the transport destination. At this time, the first and second arms 411 and 412 follow the movement of the robot 2 and rotate around the first and second rotation axes Ja and Jb, thereby allowing the horizontal movement of the operated part 42. Ru.

Here, as described above, in the assisting device 4, the relative positional relationship in the horizontal direction between the base 40 and the operated part 42 is maintained by the connecting part 44. Therefore, during step S106, it is possible to prevent the linear body 453 from tilting with respect to the vertical direction, as shown in FIG. 9, due to a delay in the movement mechanism 41 following the movement of the robot 2. can. As shown in the figure, when the filament body 453 is tilted from the vertical direction, a horizontal component force Fh is generated in the tension F of the filament body 453, and the weight of the workpiece W is added to the robot 2 by that amount. Become. If this weight exceeds the payload, the robot 2 may malfunction, come to an emergency stop, or break down, hindering smooth work. According to the present embodiment, such problems are less likely to occur, and the weight of the workpiece W applied to the robot 2 during step S106 can be kept constant, so that smooth conveyance work can be performed.

Next, in step S107, the robot control device 3 moves the robot 2 to lower the workpiece W and place it at the destination, as shown in FIG. In addition, since the shock when placing the workpiece W is alleviated and absorbed by the damper device 424, damage and failure of the workpiece W can be suppressed. At this time, the control device 46 feeds back the load torque of the motor 452 detected by the force sensor 43 to the torque command value of the motor 452, so that the torque Ft and the difference between the gravity Fm and the gear resistance f become equal. Controls the drive of the motor 452. In other words, the driving of the motor 452 is controlled so that Ft=Fm−f. Thereby, the load applied to the robot 2 at step S107 can be sufficiently reduced, and the workpiece W can be lowered safely. Note that, as long as the load applied to the robot 2 is less than or equal to the payload of the robot 2, the present invention is not limited to this, and for example, Ft<Fm−f may be satisfied.

Next, the control device 46 stops driving the motor 452 in step S108. Next, in step S109, the robot control device 3 moves the robot 2 to remove the hook 425a from the workpiece W and release the locked state. Next, the robot control device 3 moves the robot 2 to the standby position in step S110. With the above steps, the conveyance work is completed.

[Assembly work process S2]
In the assembly work process S2, first, as shown in FIG. 11, in step S201, the robot control device 3 moves the robot 2 to move the end effector 23 to the supply position of the assembly part W1. Next, in step S202, the robot control device 3 moves the robot 2 to grip the assembly part W1 with the end effector 23. Next, in step S203, the robot control device 3 moves the robot 2 to move the assembly part W1 to the work position. Next, as shown in FIG. 12, the robot control device 3 moves the robot 2 and attaches the assembly part W1 to the workpiece W in step S204. With the above, the assembly work process S2 is completed.

In this way, according to the robot system 1, the transport work and the predetermined work other than the transport work can be performed consecutively within the same work area. Therefore, the robot system 1 can exhibit excellent productivity. In particular, by setting the predetermined work to be performed on the workpiece W as in this embodiment, it is possible to smoothly transition from the transport work to the predetermined work, and the productivity of the robot system 1 is further improved. Note that the prescribed work other than the transport work is not limited to the above-mentioned assembly work, but includes work performed on the workpiece W such as processing work such as screw tightening, cutting, and polishing, painting work, and inspection work. Good too. Further, the work may be a work other than the work performed on the work W, such as a transport work of transporting another work whose weight is less than the payload capacity.

The robot system 1 has been described above. As described above, the assisting device 4 included in the robot system 1 includes a base 40, a moving mechanism 41 that supports the base 40 in a horizontally movable state, and a locking mechanism that locks the workpiece W as an object. An operated part 42 that is operated by the robot 2 and includes a stop part 425 and a connected part 423 that is connected to the robot 2, a force sensor 43 that detects the force applied to the operated part 42, and a base 40 and a connected part 423 that are connected to the robot 2. A connecting part 44 that connects the operating part 42 and restricts horizontal displacement of the operated part 42 with respect to the base 40, a drive mechanism 45 that raises and lowers the operated part 42, and a force detected by the force sensor 43. and a control device 46 that controls the drive of the drive mechanism 45 based on the drive mechanism 45 . According to such an assisting device 4, the relative positional relationship in the horizontal direction between the base 40 and the operated portion 42 is maintained by the connecting portion 44. Therefore, fluctuations in the weight of the workpiece W applied to the robot 2 while the workpiece W is being transported are suppressed, and the workpiece W can be transported smoothly.

Further, as described above, the connecting portion 44 expands and contracts in the vertical direction as the operated portion 42 moves up and down. By expanding and contracting the connecting portion 44 in this manner, the height (upper end position) of the connecting portion 44 can be kept constant regardless of whether the operated portion 42 is raised or lowered. Therefore, for example, compared to a configuration in which the connecting part 44 cannot expand and contract and moves up and down as the operated part 42 goes up and down, as in the second embodiment described later, the required amount is required to arrange the robot system 1. You can make the space smaller.

Further, as described above, the connecting portion 44 includes a plurality of sliding members 440 that slide against each other in the vertical direction. This simplifies the configuration of the connecting portion 44.

Further, as described above, the plurality of sliding members 440 include a cylindrical first sliding member 441, which is inserted into the first sliding member 441, and is slidable in the vertical direction with respect to the first sliding member 441. A moving cylindrical second sliding member 442 is included. This simplifies the configuration of the connecting portion 44.

Further, as described above, the second sliding member 442 rotates with respect to the first sliding member 441 around the central axis O, which is an axis extending in the vertical direction. This allows the operated section 42 to rotate around the central axis O with respect to the base 40, allowing twisting between the operated section 42 and the base 40. Therefore, the degree of freedom in the direction of the operated part 42 is increased, and the conveyance work described below can be performed smoothly. In addition, external force (torque) around the central axis O is less likely to be applied to the assisting device 4, and breakdowns, damage, etc. of the assisting device 4 can be effectively suppressed.

Further, as described above, the drive mechanism 45 includes a filament body 453 connected to the operated portion 42 and a motor 452 as a drive source that winds up or sends out the filament body 453. . This simplifies the configuration of the drive mechanism 45. Further, excellent responsiveness can be exhibited, and the ability of the assisting device 4 to follow the movements of the robot 2 can be improved.

Furthermore, as described above, the operated section 42 further includes a damper device 424 that is located between the connected section 423 and the locking section 425 and expands and contracts in the vertical direction. By expanding and contracting the damper device 424, the impact generated during the operation of the robot 2 is alleviated and absorbed, and damage to the assist device 4 and the workpiece W, failure, etc. can be effectively suppressed. Further, by expanding and contracting the damper device 424, it is possible to tolerate misalignment from the teaching position, allowing the robot 2 to perform work smoothly.

Further, as described above, the moving mechanism 41 is connected to the first arm 411 that rotates around the first rotation axis Ja along the vertical direction, and is connected to the first arm 411 in the vertical direction with respect to the first arm 411. The second arm 412 rotates around a second rotation axis Jb along the axis Jb, and the base 40 is disposed on the second arm 412. This simplifies the configuration of the moving mechanism 41.

Further, as described above, the robot system 1 includes a robot 2 that performs a transport operation to transport a work W as an object, and an assist device 4 that provides assistance to the robot 2. The assisting device 4 also includes a base 40, a moving mechanism 41 that moves the base 40 in the horizontal direction, a locking part 425 that locks the workpiece W, and a connected part 423 that is connected to the robot 2. An operated part 42 operated by the robot 2, a force sensor 43 that detects the force applied to the operated part 42, a base 40 and the operated part 42 are connected, and the operated part 42 is moved in the horizontal direction with respect to the base 40. , a drive mechanism 45 that raises and lowers the operated part 42 , and a control device 46 that controls the drive of the drive mechanism 45 based on the force detected by the force sensor 43 . There is. According to such a robot system 1, the relative positional relationship in the horizontal direction between the base 40 and the operated part 42 is maintained by the connecting part 44. Therefore, fluctuations in the weight of the workpiece W applied to the robot 2 while the workpiece W is being transported are suppressed, and the workpiece W can be transported smoothly.

Further, as described above, the robot 2 has the end effector 23 as a robot connecting part connected to the connected part 423, and during transportation work, the end effector 23 is connected to the connected part 423, and the robot 2 is connected to the connected part 423. The end effector 23 is not connected to the connected portion 423 during a predetermined work different from the work. According to such a configuration, the transport work and the predetermined work other than the transport work can be performed consecutively within the same work area. Therefore, the robot system 1 can exhibit excellent productivity.

Further, as described above, the predetermined work is a work performed on the workpiece W. Thereby, the transfer work can be smoothly transitioned to the predetermined work, and the productivity of the robot system 1 can be further improved.

<Second embodiment>
FIG. 13 is a diagram showing the overall configuration of a robot system according to the second embodiment.

The robot system 1 of this embodiment is the same as the robot system 1 of the first embodiment described above, except that the configuration of the assist device 4 is different. Therefore, in the following description, the differences between this embodiment and the above-described first embodiment will be mainly explained, and the explanation of similar matters will be omitted. Furthermore, in the figures of this embodiment, the same components as those of the embodiment described above are denoted by the same reference numerals.

As shown in FIG. 13, in the assisting device 4 of this embodiment, the second arm 412 also serves as the base 40. Further, the drive mechanism 45 includes a ball screw nut 459 supported by the second arm 412, and a motor 452 as a drive source for rotating the ball screw nut 459. Further, the connecting portion 44 is constituted by a spline shaft 449 inserted through a ball screw nut 459, and cannot be expanded or contracted. In the assist device 4 having such a configuration, when the motor 452 rotates the ball screw nut 459 in the forward direction, the spline shaft 449 rises, and the operated portion 42 rises accordingly. Conversely, when the motor 452 rotates the ball screw nut 459 in the opposite direction, the spline shaft 449 descends, and the operated portion 42 descends accordingly.

The second embodiment as described above can also exhibit the same effects as the first embodiment described above.

Although the assistance device and robot system of the present invention have been described above based on the illustrated embodiments, the present invention is not limited thereto, and the configuration of each part may be any configuration having similar functions. can be replaced with Moreover, other arbitrary components may be added to the present invention. Further, each embodiment may be combined as appropriate.

DESCRIPTION OF SYMBOLS 1... Robot system, 2... Robot, 21... Base, 22... Robot arm, 221... First robot arm, 222... Second robot arm, 223... Third robot arm, 224... Fourth robot arm, 225... Third robot arm. 5 robot arm, 226... sixth robot arm, 23... end effector, 24... force sensor, 251... first drive mechanism, 252... second drive mechanism, 253... third drive mechanism, 254... fourth drive mechanism, 255 ...Fifth drive mechanism, 256...Sixth drive mechanism, 3...Robot control device, 4...Auxiliary device, 40...Base, 41...Movement mechanism, 410...Fixed part, 411...First arm, 412...Second arm, 42... Operated part, 421... Eye bolt, 422... Base, 422a... Bottom plate, 422b... Top plate, 422c... Support column, 423... Connected part, 424... Damper device, 424a... Base, 424b... Movable part, 424c... Damper , 425...Locking part, 425a...Hook, 43...Force sensor, 44...Connecting part, 440...Sliding member, 441...First sliding member, 442...Second sliding member, 443...Third sliding member , 449...Spline shaft, 45...Drive mechanism, 451...Pulley, 452...Motor, 453...Striated body, 454...Reducer, 459...Ball screw nut, 46...Control device, F...Tension, Fh...Component force, Ja ...first rotation axis, Jb...second rotation axis, O...center axis, S1...transport work process, S101...step, S102...step, S103...step, S104...step, S105...step, S106...step, S107...step, S108...step, S109...step, S110...step, S2...assembly work process, S201...step, S202...step, S203...step, S204...step, W...workpiece, W1...assembly part

Claims (11)

base and
a moving mechanism that moves the base in a horizontal direction;
an operated part that is operated by the robot and includes a locking part that locks an object and a connected part that is connected to the robot;
a force sensor that detects a force applied to the operated part;
a connecting part that connects the base and the operated part and restricts horizontal displacement of the operated part with respect to the base;
a drive mechanism that raises and lowers the operated section;
An assisting device comprising: a control device that controls driving of the drive mechanism based on the force detected by the force sensor. The assisting device according to claim 1, wherein the connecting portion expands and contracts in the vertical direction as the operated portion moves up and down. The assisting device according to claim 2, wherein the connecting portion includes a plurality of sliding members that slide against each other in a vertical direction. The plurality of sliding members include a cylindrical first sliding member and a cylindrical second sliding member that is inserted into the first sliding member and slides in a vertical direction with respect to the first sliding member. The assistance device according to claim 3, further comprising a movable member. The assisting device according to claim 4, wherein the second sliding member rotates about an axis along the vertical direction with respect to the first sliding member. The drive mechanism includes a linear body connected to the operated section;
The assisting device according to any one of claims 2 to 5, further comprising a drive source that winds up or sends out the filament. The assisting device according to claim 1, wherein the operated part further includes a damper device that is located between the connected part and the locking part and expands and contracts in the vertical direction. The moving mechanism includes a first arm that rotates around a first rotation axis that extends in the vertical direction, and a second arm that rotates around a second rotation axis that is connected to the first arm and extends in the vertical direction with respect to the first arm. a second arm that rotates;
The assisting device according to claim 1, wherein the base is disposed on the second arm. A robot that performs transportation work to transport objects,
an assisting device that provides assistance to the robot;
The assisting device includes a base;
a moving mechanism that moves the base in a horizontal direction;
an operated part that is operated by the robot and includes a locking part that locks the object and a connected part that is connected to the robot;
a force sensor that detects a force applied to the operated part;
a connecting part that connects the base and the operated part and restricts horizontal displacement of the operated part with respect to the base;
a drive mechanism that raises and lowers the operated section;
A robot system comprising: a control device that controls driving of the drive mechanism based on the force detected by the force sensor. The robot has a robot connecting part connected to the connected part,
During the conveyance work, the robot connecting part is connected to the connected part,
The robot system according to claim 9, wherein the robot connecting part is not connected to the connected part during a predetermined work different from the transport work. The robot system according to claim 10, wherein the predetermined work is a work performed on the object.

Images