JP2023047742A - Work device - Google Patents

Abstract

To provide a work machine that can reduce vibrations of a tip end part of an actuating mechanism, with good responsiveness, during high-speed operation or with respect to complicate and finely-tuned operation.SOLUTION: A work device 1 comprises a link operation device 7, a movement mechanism 62 and a control device Cu. In the link operation device 7, a link hub 13 at a tip end side is connected to a link hub 12 at a base end side through a link mechanism 14 so that a posture thereof can be changed. In the movement mechanism 62, the link hub 12 at the base end side is mounted on a second linearly moving actuator 66 acting as an output part. The control device Cu controls an actuator 10 for controlling a posture of the link operation device 7 and first, second and third linearly moving actuators 65, 66 and 67. The control device Cu controls other actuators so that inertia force generated in either of the movement mechanism 62 and the link operation device 7 is cancelled.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a work device used for equipment that requires high speed, high precision, wide operating range, and fine movement, such as medical equipment or industrial equipment.

A conventional technology proposes a robot arm that includes a vibration detection unit that detects vibration and a vibration correction unit that applies a force in the opposite phase to the vibration detected by the vibration detection unit (Patent Document 1).

JP 2013-169619 A

In the robot arm disclosed in Patent Document 1, the joints are arranged rotatably in series, so the structure becomes complicated. had to set. In addition, since each joint is arranged rotatably in series, it is not possible to apply vibrations in opposite phases in various directions by driving only some of the joints. You have to drive the whole thing. In this case, since the inertia of the robot arm as a whole is large, responsiveness is low, and there is a problem that vibration cannot be suppressed during high-speed operation or complicated fine-grained operation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a working device capable of reducing vibrations at the tip of an operating mechanism with good responsiveness during high-speed operations or complicated fine-grained operations.

The working device of the present invention includes an operating mechanism 7 and a moving mechanism 62,
The actuating mechanism 7 is for attitude control, in which the distal end member 40 is connected to the proximal end member 6 via the link mechanism 14 so as to be able to change its attitude, and the attitude of the distal end member 40 with respect to the proximal end member 6 is arbitrarily changed. is provided with an actuator 10 of
The moving mechanism 62 is a working device in which the moving drive actuators 65, 66, 67, and Ra are provided as output units, and the base end member 6 is attached to the moving drive actuators,
A controller Cu for controlling the attitude control actuator 10, the movement drive actuators 65, 66, 67, and Ra is provided. The other actuator is controlled so as to cancel the inertial force generated in

According to this configuration, by controlling the actuator of either the moving mechanism 62 or the operating mechanism 7 so as to cancel the inertial force due to the acceleration or deceleration of either the moving mechanism 62 or the operating mechanism 7, the tip of the tip member 40 can be moved. It is possible to reduce the vibration that occurs in the part. Therefore, it is possible to reduce the vibration of the tip portion of the actuating mechanism 7 with good responsiveness during high-speed operation or complicated fine-grained operation.

The control device Cu causes inertia generated in one of the moving mechanism 62 and the actuating mechanism 7 to generate inertia in the direction opposite to at least the component force of the moving direction component of the one moving mechanism 62 and the operating mechanism 7 . actuators may be controlled.
The force component is a directional force due to vibration.
In this case, since inertia is generated in the direction opposite to at least the component force of the moving direction component of one of the inertia forces, the vibration of the operating mechanism 7 can be effectively and quickly reduced with a slight movement.

Three or more sets of the link mechanisms 14 are provided, and each of the link mechanisms 14 has proximal and distal ends rotatably connected to the link hub 12 on the proximal side and the link hub 13 on the distal side, respectively. and a center link member 17 having both ends rotatably connected to the other ends of the end link members 15 and 16 on the base end side and the tip end side, respectively, and the three or more sets of Two or more sets of the link mechanisms 14 out of the link mechanisms 14 may be provided with the actuators 10 for attitude control.
According to this configuration, the link hub 12 on the base end side, the link hub 13 on the tip end side, and the link mechanism 14 of three or more pairs are configured such that the link hub 13 on the tip end side rotates about two orthogonal axes relative to the link hub 12 on the base end side. A rotatable two-degree-of-freedom mechanism is constructed. In other words, the link hub 13 on the distal end side of the link hub 12 on the proximal end side has two degrees of freedom in rotation and a changeable posture. This two-degrees-of-freedom mechanism is compact, but allows a wide movable range of the link hub 13 on the distal side with respect to the link hub 12 on the proximal side.

The control device Cu calculates an inertia force calculation unit 68 that calculates the inertia force and its direction, and an operation amount that generates the inertia in the opposite direction from the inertia force calculated by the inertia force calculation unit 68 and its direction. and a control unit 70 that performs control to adjust the timing of executing the motion based on the amount of motion calculated by the motion amount calculator 69 . In this way, the control device Cu calculates the amount of motion that causes inertia in the opposite direction and adjusts the timing of executing the motion, so that one of the moving mechanism 62 and the actuating mechanism 7 moves to the other side. , it is possible to generate inertia in the opposite direction.

The inertia force computing unit 68 computes the inertial force of the movement driving actuators 65, 66, 67, Ra at the time of acceleration or deceleration from the movement direction and speed of the movement driving actuators 65, 66, 67, Ra. You may In this case, since the direction and magnitude of the inertial force can be easily calculated from the command values of the moving direction and speed of the actuators 65, 66, 67, Ra for driving movement, a vibration detector such as a vibration sensor can be easily calculated. is not necessary, and the structure can be simplified.

The movement amount calculation section 69 may calculate the movement amount by decomposing the inertial force and its direction calculated by the inertia force calculation section 68 into the tangential plane direction of the movement range of the operating mechanism 7 . Due to the structure of the actuating mechanism 7, the vibration is caused by the force in the tangential plane direction of the operating range of the actuating mechanism 7. Vibration of the operating mechanism 7 is effectively reduced with a slight movement by resolving the inertial force of time in the tangential plane direction of the operating range of the operating mechanism 7 and adding inertia in the opposite direction to the component force. be able to.

The moving mechanism 62 may include a linear motion unit 63 including first, second and third linear motion actuators 65, 66 and 67 that advance and retreat in three orthogonal axial directions. In this case, by combining the linear motion unit 63 and the operating mechanism 7, the operating mechanism 7 can be moved in various directions at high speed. As a result, it is possible to provide a working device that can be applied to various types of works and that is capable of shortening the tact time.

The moving mechanism 62 may have a rotary actuator Ra serving as an output section. In this case, by rotating the actuating mechanism 7 with the rotary actuator Ra, it is possible to widen the working range for the workpiece and to perform fine-grained movements. Therefore, it is possible to shorten the setup change work.

This work device may be the visual inspection devices 1A and 1B in which the image processing device Eg is mounted on the operating mechanism 7. FIG. In this case, the appearance inspection process, which has been visually inspected from various directions until now, can be automatically performed at high speed and with high accuracy. Also, by reducing the vibration of the image processing device Eg, it is possible to obtain an image without blurring.

According to the working device of the present invention, the actuator of one of the moving mechanism and the operating mechanism is controlled so as to cancel the inertial force generated in the other mechanism. Vibration at the tip of the can be reduced with good responsiveness.

1 is a block diagram of a control system of a working device according to a first embodiment of the present invention; FIG. FIG. 3 is a perspective view of a link actuating device of the working device; It is a perspective view which shows the other attitude|position of the same link actuating device. FIG. 5 is a partial cross-sectional view taken along line IIC-IIC of FIG. 4; It is a front view of the same link actuation device. It is the front view of the simple model which abbreviate|omitted two link mechanisms of the same link actuation apparatus. It is the figure which expressed one link mechanism of the same link actuation device with a straight line. It is a figure which shows the structural example which combined the same link actuator and a direct-acting unit. It is a perspective view which shows the operation|movement range of the same link actuation apparatus. It is a front view which shows the operation|movement range of the same link actuation apparatus. It is a perspective view which shows the example which produces|generates inertia of an opposite direction in the same link actuator. FIG. 5 is a diagram conceptually showing an example of generating inertia in the opposite direction in the same link actuation device; It is a perspective view of a visual inspection device in which an image processing device is mounted on the same link actuating device. FIG. 11 is a perspective view of a visual inspection device in which another image processing device is mounted on the link actuating device; FIG. 9B is a front view showing a configuration example of the visual inspection apparatus of FIG. 9A; FIG. 9B is a front view showing a configuration example of the visual inspection apparatus of FIG. 9B; It is a front view of a working device according to a second embodiment of the present invention. It is a front view of a working device according to a third embodiment of the present invention.

[First embodiment]
A working device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 10B.
As shown in FIG. 1, the working device 1 includes a link actuating device 7 as an actuating mechanism, a moving mechanism 62, and a control device Cu. This working device 1 is used for, for example, medical equipment or industrial equipment.
<General structure of working device>
The working device 1 is configured by combining a link actuating device 7 and a linear motion unit 63 as a moving mechanism 62 . A linear motion unit 63 that advances and retreats in orthogonal three-axis directions is installed on a stand (not shown) or the like, and a link actuator 7 is attached to a movement drive actuator serving as an output portion of the linear motion unit 63 . The work device 1 performs work by positioning an end effector attached to the tip member 40 of the link actuating device 7 with respect to a work (not shown). The link actuating device 7 and the linear motion unit 63 are connected to a control device Cu and synchronously controlled by the control device Cu.

<About the link actuator>
As shown in FIG. 2A , the link actuating device 7 includes a parallel link mechanism 9 and an attitude control actuator 10 that actuates the parallel link mechanism 9 .
<Parallel link mechanism>
The parallel link mechanism 9 connects a link hub 13 on the front end side to a link hub 12 on the base end side via three sets of link mechanisms 14 so that the posture can be changed. The number of sets of link mechanisms 14 may be four or more. In FIG. 4, only one set of linkages 14 is shown and the remaining two linkages are omitted.

Each link mechanism 14 has an end link member 15 on the base end side, an end link member 16 on the tip end side, and a center link member 17, and forms a four-bar linkage link mechanism composed of four rotational pairs.
As shown in FIG. 2B, the proximal and distal end link members 15 and 16 are substantially L-shaped, and one end can rotate to the proximal link hub 12 and the distal link hub 13, respectively. connected to As shown in FIG. 4, the center link member 17 is rotatably connected to both ends of the end link members 15 and 16 on the base end side and the tip end side, respectively.

The parallel link mechanism 9 has a structure in which two spherical link mechanisms are combined. The central axis of each rotational pair of the proximal side link hub 12 and the proximal side end link member 15 and each rotational pair of the proximal side end link member 15 and the central link member 17 is aligned with the proximal side. They intersect at the spherical link center PA. Similarly, the central axis of each rotational pair of the tip-side link hub 13 and the tip-side end link member 16, and each rotational pair of the tip-side end link member 16 and the center link member 17 is the tip-side spherical surface. They intersect at the link center PB.

The distance between the center of the rotational pair between the link hub 12 on the proximal side and the end link member 15 on the proximal side and the spherical link center PA on the proximal side is the same. The distance between the center of the rotational pair of the end link member 15 on the proximal side and the center link member 17 and the spherical link center PA on the proximal side is the same. Similarly, the distance between the center of the rotational pair between the tip-side link hub 13 and the tip-side end link member 16 and the tip-side spherical link center PB is the same. The distance between the center of the rotational pair of the end link member 16 and the central link member 17 on the tip side and the center PB of the spherical link on the tip side is the same.

The central axes of each rotational pair of the proximal and distal end link members 15, 16 and the central link member 17 may have an intersection angle γ or may be parallel.
The central axis of each rotational pair between the proximal side link hub 12 and the proximal side end link member 15, and the central axis of each rotational pair between the proximal side end link member 15 and the central link member 17 The arm angle, which is the angle formed by , is defined as a defined angle.

The three sets of link mechanisms 14 are geometrically identical. The geometrically identical shape is represented by a geometric model in which the link members 15, 16, and 17 are represented by straight lines as shown in FIG. It means that the base end side portion and the tip end side portion of the central link member 17 with respect to the central portion are symmetrical regardless of the posture of the model. FIG. 5 is a diagram showing a set of link mechanisms 14 represented by straight lines. The parallel link mechanism 9 of this embodiment is of a rotationally symmetrical type, and is composed of a proximal side link hub 12 and a proximal side end link member 15, and a distal side link hub 13 and a distal side end link member 16. The positional relationship is rotationally symmetrical with respect to the center line C of the central link member 17 . A central portion of each central link member 17 is positioned on a common orbital circle.

A link hub 12 on the proximal side, a link hub 13 on the distal side, and three sets of link mechanisms 14 provide 2 freedoms in which the link hub 13 on the distal side is rotatable about two orthogonal axes with respect to the link hub 12 on the proximal side. A degree mechanism is configured. In other words, the link hub 13 on the distal end side of the link hub 12 on the proximal end side has two degrees of freedom in rotation and a changeable posture. This two-degrees-of-freedom mechanism is compact, but allows a wide movable range of the link hub 13 on the distal side with respect to the link hub 12 on the proximal side.

For example, through the spherical link centers PA and PB on the proximal and distal sides, each rotational pair of the link hubs 12 and 13 on the proximal and distal sides and the end link members 15 and 16 on the proximal and distal sides Assuming that the straight line perpendicularly intersecting the central axis O1 (FIG. 2A) is the central axis QA, QB of the link hubs 12, 13 on the proximal side and the distal side, the central axis QA of the link hub 12 on the proximal side and the distal side The maximum bending angle _θmax , which is the maximum value of the bending angle θ with the center axis QB of the link hub 13, can be set to about 90°. Further, as shown in FIG. 3, the turning angle φ of the link hub 13 on the distal side with respect to the link hub 12 on the proximal side can be set within the range of 0° to 360°. As shown in FIG. 5, the bending angle .theta. is the vertical angle at which the central axis QB of the link hub 13 on the distal side is inclined with respect to the central axis QA of the link hub 12 on the proximal side. On the other hand, the turning angle φ is a horizontal angle at which the central axis QB of the link hub 13 on the distal side is inclined with respect to the central axis QA of the link hub 12 on the proximal side. Note that the maximum bending angle θ _max may be 90° or more.

The posture of the link hub 13 on the front end side relative to the link hub 12 on the base end side is changed with the intersection point O of the center axis QA of the link hub 12 on the base end side and the center axis QB of the link hub 13 on the front end side as the center of rotation. will be The solid line in FIG. 7B indicates a state in which the central axis QA (FIG. 4) of the link hub 12 on the base end side and the central axis QB (FIG. 4) of the link hub 13 on the distal end side are on the same line. The dashed line indicates a state in which the central axis QB (Fig. 4) of the link hub 13 on the distal end side is at a certain operating angle (bent angle) with respect to the central axis QA (Fig. 4) of the link hub 12 on the proximal side. show. As shown in FIG. 5, even if the posture of the link hub 13 on the distal end side with respect to the link hub 12 on the proximal end side changes, the distance L between the spherical link centers PA and PB on the proximal side and the distal side does not change.

In this parallel link mechanism 9, when all of the following conditions are satisfied, from geometrical symmetry, the proximal side link hub 12 and the proximal side end link member 15, the distal side link hub 13 and the distal side , the end link members 16 move in the same manner. Therefore, when the rotation is transmitted from the proximal side to the distal side, the parallel link mechanism 9 functions as a constant velocity universal joint in which the proximal side and the distal side have the same rotation angle and rotate at a constant speed.

Condition 1: As shown in FIGS. 2C and 5, the centers of the rotational pairs of the link hubs 12, 13 on the proximal and distal sides and the end link members 15, 16 on the proximal and distal sides in each link mechanism 14 The angle α of the axes O1, O2 and the lengths from the spherical link centers PA, PB on the proximal side and the distal side are equal to each other.
Condition 2: the central axis of the rotational pair of the link hubs 12, 13 on the proximal and distal sides of each link mechanism 14 and the end link members 15, 16 on the proximal and distal sides of each link mechanism 14; The central axes of the rotational pairs of the end link members 15, 16 and the central link member 17 intersect the spherical link centers PA, PB on the proximal and distal sides on the proximal and distal sides, respectively.
Condition 3: The geometric shapes of the proximal end link member 15 and the distal end link member 16 are the same.
Condition 4: The geometric shapes of the proximal side portion and the distal side portion of the central link member 17 are the same.
Condition 5: With respect to the plane of symmetry of the central link member 17, the angular positional relationship between the central link member 17 and the proximal and distal end link members 15 and 16 is the same on the proximal and distal sides. .

As shown in FIG. 2A , the link hub 12 on the base end side has a plate-like base end member 6 and three rotating shaft connecting members 21 provided integrally with the base end member 6 . The base end member 6 has a circular through hole 6a in its central portion, and three rotating shaft connecting members 21 are arranged at equal intervals in the circumferential direction around this through hole 6a. The center of the through hole 6a is located on the center axis QA of the link hub 12 on the base end side shown in FIG. A rotating shaft 22 shown in FIG. 3 is rotatably connected to each rotating shaft connecting member 21 so that its axis intersects the central axis QA of the link hub 12 on the base end side. One end of the proximal end link member 15 is connected to the rotating shaft 22 .

The link hub 13 on the front end side has a flat tip member 40 and three rotating shaft connecting members 41 provided on the bottom surface of the tip member 40 at equal intervals in the circumferential direction. The center of the circumference where each rotating shaft coupling member 41 is arranged is positioned on the central axis QB of the link hub 13 on the tip side. Each rotary shaft connecting member 41 is rotatably connected to a rotary shaft 43 whose axis intersects the central axis QB of the link hub 13 on the tip end side. One end of the end link member 16 on the distal end side is connected to the rotating shaft 43 . A rotary shaft 45 rotatably connected to the other end of the central link member 17 is connected to the other end of the end link member 16 on the tip side.

<Actuator for attitude control>
The attitude control actuator 10 shown in FIG. 2A is a rotary actuator provided with a speed reduction mechanism 52, and is installed coaxially with the rotating shaft 22 on one plane of the proximal member 6 of the link hub 12 on the proximal side. there is The attitude control actuator 10 and the speed reduction mechanism 52 are provided integrally, and the speed reduction mechanism 52 is fixed to the base end member 6 by a motor fixing member 53 . The actuator 10 for attitude control may be equipped with a brake.

In this example, all of the three link mechanisms 14 are provided with the attitude control actuators 10, but if at least two of the three link mechanisms 14 are provided with the attitude control actuators 10, the basic The posture of the link hub 13 on the tip side with respect to the link hub 12 on the end side can be determined.
The three attitude control actuators 10 are arranged so that their rotation axes 22 are orthogonal to the central axis QA (FIG. 4) of the link hub 12 on the base end side. is on the central axis QA (FIG. 4) of the link hub 12 on the base end side.

As shown in FIG. 3 , the link actuating device 7 rotates each attitude control actuator 10 to actuate the parallel link mechanism 9 . Specifically, when the attitude control actuator 10 is rotationally driven, the rotation is decelerated through the deceleration mechanism 52 and transmitted to the rotating shaft 22 . As a result, the angle of the end link member 15 on the proximal side with respect to the link hub 12 on the proximal side changes, and the posture of the link hub 13 on the distal side with respect to the link hub 12 on the proximal side is changed arbitrarily.

<End effector>
An end effector, which is a tip portion, is attached to the tip member 40 of the link hub 13 on the tip side. Examples of the end effector include a hand including a gripper, a cleaning nozzle, a dispenser, a welding torch, an image processing device Eg (FIGS. 9A and 9B), and the like.

The image processing equipment Eg shown in FIG. 9A has, for example, a camera Cm that captures an image of a work. The working device in this case is a visual inspection device 1A in which an image processing device Eg is mounted on a link actuating device 7, as shown in FIG. 10A. The image processing device Eg shown in FIG. 9B includes, for example, a camera Cm that captures an image of the work, a lighting fixture Le that illuminates the work, and the like. The working device in this case is a visual inspection device 1B in which an image processing device Eg is mounted on a link actuating device 7, as shown in FIG. 10B. 10A and 10B, at least the camera Cm is electrically connected to a camera control system (not shown) via wiring, and the camera control system performs various controls during photographing.

<Linear motion mechanism>
As shown in FIG. 6, an XYZ stage that advances and retreats in orthogonal three-axis directions is applied to a linear motion unit 63, which is a moving mechanism. The linear motion unit 63 has first, second and third linear motion actuators 65, 66 and 67, which are actuators for movement driving. The first direct-acting actuator 65 advances and retreats in the X-axis direction, which is the left-right direction in FIG. The second direct-acting actuator 66, which serves as an output portion, advances and retreats in the Y-axis direction, which is the front-rear direction orthogonal to the X-axis direction. The third direct-acting actuator 67 advances and retreats in the Z-axis direction perpendicular to the X-axis direction and the Y-axis direction. In this example, the Z-axis direction is set to be the vertical direction.

The first, second and third linear actuators 65, 66 and 67 are driven by motors 65a, 66a and 67a, respectively, which are driving sources, and convert the rotation of each motor 65a, 66a and 67a into linear reciprocating motion. It has a conversion mechanism (not shown) such as a ball screw. Each linear motion actuator 65, 66, 67 includes guides 65b, 66b, 67b extending along the corresponding axial direction, a slide table sliding along each of the guides 65b, 66b, 67b, motors 65a, 66a, 67a. In this example, the link hub 12 on the base end side of the link actuating device 7 is attached to the slide table of the second direct acting actuator 66 serving as the output section. By arranging the linear motion unit 63 that advances and retreats in the orthogonal three-axis directions in this way and attaching the link actuator 7 on the final stage thereof, the end effector attached to the tip member 40 can move with a high degree of freedom. It has become.

<Regarding the control system>
The controller Cu shown in FIG. 1 controls the attitude control actuator 10 of the link operating device 7 so as to cancel the inertial force due to the acceleration or deceleration of the linear motion unit 63 . Specifically, the control device Cu controls the bending angle θ and turning angle φ ( FIG. 3 ) of the link actuating device 7 during acceleration or deceleration such as positioning of the linear motion unit 63 .
During acceleration or deceleration during positioning or the like, in this example, the linear motion unit 63 is in an acceleration region from a stopped state to uniform motion, or conversely, the linear motion unit 63 changes from uniform motion to a stopped state. It means the deceleration area up to . The time of acceleration or deceleration such as the time of positioning may be hereinafter referred to as "time of settling".

At the time of stabilization, the control device Cu controls the bending angle θ and turning angle φ (FIG. 3) of the link actuating device 7 to generate inertia in the tip of the end effector in the direction opposite to that of the linear motion unit 63. To reduce the vibration generated in the end effector.

<Regarding the trajectory drawn by the tip of the link actuating device 7>
Here, when an end effector is attached to the tip member 40 of the link actuating device 7 and a mass point A at the tip of the end effector is considered, the trajectory drawn by the mass point A by the operation of the link actuating device 7 is shown in FIG. 7A. , FIG. 7B. As shown in FIG. 7A, the trajectory Ls drawn by the link actuating device 7 by the mass point A is substantially hemispherical, and the link actuating device 7 performs high-speed, highly accurate and smooth positioning within the substantially hemispherical operating range S. I do.

As shown in FIG. 6, in a configuration in which the link actuating device 7 is mounted on the final stage of the direct-acting unit 63, when the link actuating device 7 is moved by the direct-acting unit 63 as indicated by an arrow A1, inertia is generated by the movement. When the movement is completed, a force due to its inertia acts. FIG. 6 shows the inertial force F acting on the mass point A at the tip of the end effector.

<Regarding the load acting on the tip of the end effector due to the deceleration of the stage and the inertia in the opposite direction>
Attention is paid to the link actuating device 7 in the working device 1 of FIG. In FIG. 8A, in a posture (bending angle θ, turning angle φ) of the link actuating device 7, an inertial force F is applied to the mass point A by movement of at least one of the XYZ stages in the linear motion unit 63 (FIG. 6). ing.

FIG. 8B shows a conceptual diagram in which the link mechanism and the like are omitted. In FIG. 8B, the mass point A, the posture of the link actuating device (bending angle θ, turning angle φ), and the inertial force F acting on the mass point A are shown. The shaded area indicates the movement range Sa of the mass point A when the link actuating device is moved by a small angle from the current posture (the bending angle θ and the turning angle φ). The shaded motion range Sa is a partially spherical range obtained by partially cutting out a portion of the motion range S (FIG. 7A). A quadrangle Sb indicated by a chain double-dashed line in FIG.

The inertial force F caused by the movement of the linear motion unit 63 (FIG. 6) can be decomposed into a tangential plane force Ft and a perpendicular force Fn. Due to its structure, the link actuating device has high rigidity against force Fn in the perpendicular direction, but low rigidity against force Ft in the tangential plane direction. This is one of the causes of vibration.
In this embodiment, as shown in FIG. 8B, the tangential plane direction component Ft of the inertia force F is controlled by the link operating device so that the inertia Fr in the opposite direction is applied, that is, (dθ, dφ) to reduce the Ft component. Although it does not act on the Fn component in the direction perpendicular to the plane, the link actuator has high rigidity in the direction perpendicular to the plane and does not affect vibration.

[(θ, φ) → (θ + dθ, φ + dφ)], which changes from the specified posture by moving the link actuator dθ and dφ in order to reduce the inertial force, is moved to a point considering the amount of movement in advance. , the moving point may be controlled to become a designated point [(θ-dθ, φ-dφ)→(θ, φ)]. In this case, it is possible to position the link actuating device with higher accuracy.

The above functions are controlled by the controller Cu in FIG. Specifically, the control device Cu has an inertial force calculator 68 , an operation amount calculator 69 , and a controller 70 . The inertia force calculator 68 calculates the inertia force and its direction by the linear motion unit 63 . For example, the inertial force calculator 68 calculates the movement direction and speed of the first, second, and third linear actuators 65 , 66 , 67 of the linear actuator 63 from command values for these linear actuators 65 , 66 , 67 . It is possible to easily and quickly calculate the direction and magnitude of the inertial force at the time of acceleration or deceleration of the motor.

The movement amount calculator 69 calculates movement amounts (dθ, dφ) that generate inertia in the opposite direction from the current attitude (θ, φ) of the link actuating device 7 and the calculated inertial force and its direction. The motion amount calculator 69 calculates the motion amount by decomposing the inertia force and its direction calculated by the inertia force calculator 68 into the tangential plane direction of the motion range of the link actuating device 7 . The control unit 70 adjusts the timing of executing the motion based on the calculated motion amount. This timing is normally set when the linear motion actuators 65, 66, 67 are accelerated or decelerated, but it may be determined by finding an appropriate timing through either one or both of tests and simulations, for example.

<Effect>
According to the working device 1 described above, the bending angle and turning angle (θ, φ) of the link actuator 7 are controlled so as to cancel the inertial force due to the acceleration or deceleration of the linear motion unit 63, and the linear motion unit 63 and the creates opposite inertia at the tip of the end effector. As a result, vibration generated in the end effector attached to the tip member 40 of the link actuating device 7 can be reduced. Therefore, there is no need to provide a vibration detection unit such as a vibration sensor, and the vibration of the end effector can be reduced with good responsiveness during high-speed operation or complicated fine-grained operation. With this working device 1, the work can be stably performed even if the acceleration is set to be large. Therefore, the tact time can be shortened with an inexpensive configuration even during high-speed operation or complicated fine-grained operation.

The operating range of the tip of the link actuating device 7 is substantially hemispherical, and the inertial force that can be controlled by the bending angle and turning angle (θ, φ) and its direction are limited to the tangential plane direction of the substantially hemispherical surface, Due to the structure of the link actuator 7, it is the force in the tangential plane direction that causes the vibration. For this reason, the inertia force (the resultant force of the XYZ axes) during acceleration or deceleration of the linear motion unit 63 is resolved in the tangential plane direction of the operating range of the link actuator 7, and the inertial force in the opposite direction to the force in the tangential plane direction is resolved. Add As a result, the vibration of the link actuating device 7 can be effectively reduced with a slight movement.

Since the linear motion unit 63 including the first, second and third linear motion actuators 65, 66, 67 and the link actuator 7 are combined, the movement direction and speed of each linear motion actuator 65, 66, 67 The direction and magnitude of inertia force can be easily calculated from the command value of . Therefore, it is possible to simplify the structure of the working device 1 without providing a vibration detection unit such as a vibration sensor.

Further, for example, an acceleration sensor or a speed sensor can be attached to the tip of the link actuating device 7, and the control device Cu detects the direction of the inertial force generated by the movement of the linear motion unit 63 from the detected sensor output. calculate. Further, the control device Cu controls the amount of movement (dθ, dφ) of the link actuating device 7 from the current posture (θ, φ) of the link actuating device 7 to the inertial force of the linear motion unit 63 whose inertia is in the direction opposite to the tangential plane direction. It has an arithmetic function to calculate Therefore, it is possible to efficiently generate inertia in the opposite direction to the movement of the linear motion unit 63 on the link actuating device side.

By the way, when an image processing unit such as a camera or a lighting device is mounted on the end effector, the image may be blurred if there is vibration during shooting. Although it is possible to obtain a blur-free image by shortening the exposure time, the amount of light is required, and the options for lighting fixtures that can be mounted are limited.

In this embodiment, when the end effector is the camera Cm shown in FIG. 9A, or the image processing device Eg including the camera Cm and lighting fixture Le shown in FIG. It is possible to acquire an image without blurring. Therefore, the degree of freedom in design can be increased by increasing the options of image processing devices that can be mounted. In addition, depending on the usage conditions, it is possible to select the image processing equipment Eg without lighting fixtures shown in FIG. 9A, and the cost can be reduced as compared with the image processing equipment with lighting fixtures. In addition, by using visual inspection apparatuses 1A (Fig. 10A) and 1B (Fig. 10B) equipped with image processing equipment Eg, the visual inspection process, which has been visually inspected by humans from various directions, can be performed at high speed and with high precision. be able to do it automatically.

<About other embodiments>
In the following description, the same reference numerals are given to the parts corresponding to the items previously described in each embodiment, and redundant description is omitted. When only a portion of the configuration is described, the other portions of the configuration are the same as those previously described unless otherwise specified. The same configuration has the same effect. It is possible not only to combine the parts specifically described in each embodiment, but also to partially combine the embodiments if there is no problem with the combination.

[Second embodiment: FIG. 11 (rotary actuator)]
The moving mechanism 62 is not limited to the linear motion unit described above, and a rotary actuator Ra shown in FIG. 11 may be applied. In this working device 1C, a rotary actuator (movement driving actuator) Ra that serves as an output portion of the moving mechanism 62 is installed on a frame or the like (not shown). 12 is attached. In the working device 1C of this example, the center axis QA (see FIG. 4) of the link hub 12 on the base end side of the link actuating device 7 and the rotation axis Ca of the rotary actuator Ra are provided coaxially.

In this case, if the direction of the inertial force of the rotary actuator Ra can be detected, the link actuating device 7 can reduce the tangential inertial force. Further, by rotating the link actuating device 7 with the rotary actuator Ra, a large work range can be secured for the work, and fine movement can be performed. Therefore, it is possible to shorten the setup change work. Other effects similar to those described above are obtained.

[Third Embodiment: Fig. 12 (linear motion unit + rotary actuator)]
As shown in FIG. 12, the moving mechanism 62 may be a combination of a linear motion unit 63 and a rotary actuator Ra. In this working device 1D, a linear motion unit 63 is installed on a frame or the like (not shown), and a second linear motion actuator 66, which is an output portion of the linear motion unit 63, is connected to a link actuator 7 via a rotary actuator Ra. A proximal link hub 12 is attached. In this case, the end effector attached to the tip member 40 of the link actuating device 7 can move with a higher degree of freedom through the linear motion by the linear motion unit 63 and the rotational motion by the rotary actuator Ra. Other effects similar to those described above are obtained.

The linear motion units 63 of the first and third embodiments each employ an XYZ stage that advances and retreats in the directions of the three axes XYZ. configuration may be used.
A vertically articulated robot or a horizontally articulated robot may be applied as the movement mechanism, and a link actuator may be attached to the tip of the robot serving as the output unit.

Although it has been described above that the inertial force generated by the moving mechanism is canceled by the link actuator, the reverse is also possible, and the inertial force generated by the link actuator may be canceled by the moving mechanism. Specifically, the control device Cu in FIG. to control. In this case, the inertia force calculation unit 68 of the control device Cu calculates the inertia force during acceleration or deceleration of the tip of the end effector of the attitude control actuator 10 from the moving direction and speed of the attitude control actuator 10 . However, since there is no restriction on the inertia in the reverse direction depending on the method of the moving mechanism, it is possible to generate an operation that completely cancels the inertial force of the link actuating device.

Although the link actuating device is illustrated as a device with a parallel link structure, a pan/tilt structure (not shown) may be applied as the actuating mechanism as long as it is capable of controlling the bending angle θ and the turning angle φ. good.

Although the embodiments of the present invention have been described above, the embodiments disclosed this time are illustrative in all respects and are not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the meaning and range of equivalents of the scope of the claims.

DESCRIPTION OF SYMBOLS 1, 1C, 1D... Working apparatus, 1A, 1B... Appearance inspection apparatus (working apparatus), 6... Base end member, 7... Link operating device (operating mechanism), 10... Actuator for attitude control, 12... Base end side 13... Tip side link hub 14... Link mechanism 15... Base end side end link member 16... Tip side end link member 17... Central link member 40... Tip member 62 ... moving mechanism, 63 ... linear motion unit, 65, 66, 67 ... first, second and third linear motion actuators (movement drive actuators), 68 ... inertial force calculation section, 69 ... operation amount calculation section, 70... control section, Cu... control device, Eg... image processing device, Ra... rotary actuator

Claims (9)

Equipped with an operating mechanism and a moving mechanism,
The operating mechanism includes a distal member connected to a proximal member via a link mechanism so as to be able to change its posture, and an actuator for posture control that arbitrarily changes the posture of the distal member relative to the proximal member,
The movement mechanism has a movement drive actuator that serves as an output unit, and the work device includes the base end member attached to the movement drive actuator,
A control device is provided for controlling the attitude control actuator and the movement drive actuator, and the control device controls the actuator so as to cancel the inertial force generated in one of the movement mechanism and the actuation mechanism. A working device that controls 2. The work apparatus according to claim 1, wherein the control device controls, of the inertia force generated in either one of the moving mechanism and the operating mechanism, a force in a direction opposite to at least a component force of the moving direction component of the one of the moving mechanisms. A working device that controls the other actuator to create inertia. 3. The working device according to claim 1, further comprising three or more sets of said link mechanisms, each of said link mechanisms being rotatably connected at one end to a base end side link hub and a distal end side link hub. and a central link member having both ends rotatably connected to the other ends of the proximal and distal end link members, wherein the 3 A working device, wherein two or more sets of link mechanisms among the set or more link mechanisms are provided with the actuators for attitude control. 4. The work device according to claim 1, wherein the control device comprises an inertia force calculation section for calculating the inertia force and its direction, and an inertia force calculated by the inertia force calculation section. and an operation amount calculation unit that calculates an operation amount that causes inertia in the opposite direction from that direction; working equipment. 5. The work device according to claim 4, wherein the inertia force calculation unit calculates the inertia force during acceleration or deceleration of the movement drive actuator from the movement direction and speed of the movement drive actuator. 6. The working device according to claim 4, wherein the movement amount calculator decomposes the inertia force calculated by the inertia force calculation unit and its direction into a tangential plane direction of the movement range of the actuation mechanism. A working device that calculates the amount of movement. 7. The working device according to any one of claims 1 to 6, wherein the moving mechanism comprises a linear motion unit including first, second and third linear motion actuators that advance and retreat in orthogonal three-axis directions. working device. 8. The working device according to any one of claims 1 to 7, wherein said moving mechanism has a rotary actuator serving as an output section. 9. The work device according to claim 1, wherein the work device is a visual inspection device in which an image processing device is mounted on the operating mechanism.

Images