Tether reel mechanism for driving robot

Abstract

To provide a reel device that can perform the actions of winding and unwinding the tether without slack.SOLUTION: The reel device mechanism is used to operate a tether 700 as a robotic arm. The reel device mechanism includes: two pulleys; an electric motor to rotate them; a spring-loaded hinge 300; a limit switch 400; and a control unit 800 to control the electric motor. Additionally, the reel device is equipped with a jig that uniquely determines the position of the fixing device at the end of the tether 700 through the winding operation. A slack detection mechanism 30 is positioned between the two pulleys and detects slack in the tether through the operation of the spring-loaded hinge 300 and the limit switch 400. Furthermore, when a fixing device interface 620 is drawn into a position determination tool 610 by the winding of the tether 700, the fixing device rotates to match its shape, thus uniquely determining the position of the fixing device.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a tether reel mechanism for driving a robot, in which a pulley for winding and unwinding a tether is rotationally driven by an electric motor. [Background technology]

[0002] As disclosed in Patent Document 1 below, there has been an invention for a robot that moves through space using a tether, which includes a system configuration for a tether extension unit inside the robot. However, in this system, the tethered arm is assumed to be guided by a separately installed extendable arm, and there is no description of how the tether can be paid out in a state where there is no external tension, such as from the ground. There is also no description of the attitude of the end device (the device that secures the tether in a predetermined position) when the tether is wound up. For this reason, it is assumed that the extendable arm will be used to control the attitude of the end device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-260436 Summary of the Invention [Problem to be solved by the invention]

[0004] The extension type device described in Patent Document 1 has a complicated mechanism and is heavy. Additionally, a reel is a device used to wind up strings as a movement mechanism for robots that use strings. However, because strings are made of a flexible material, problems can arise, such as slack occurring inside the reel, especially when the string is being unwound, causing the string to become tangled inside. [Means for solving the problem]

[0005] Therefore, the inventors of the present invention discovered that even a flexible string (tether) could be used as a new robot arm if it had a reel mechanism that could wind and unwind it without slack. Specifically, the robot driving tether reel mechanism of the present invention is characterized in that it can be unwound without slack within the reel even when no tension is applied to the tether. Furthermore, when using a tether as a robotic arm, a fixing device such as a hand or hook is required at the end of the tether to secure the tether at the destination. Because the reel and fixing device are connected by the tether, the fixing device can freely rotate around the axis of the tether. Therefore, by including the attitude determination mechanism of the present invention, the fixing device can be returned to the reel in a unique direction when the tether is wound up, and the attitude of the fixing device is uniquely determined when the tether is wound up. [Effects of the Invention]

[0006] According to the present invention, Even when there is no tension on the tether, it can be reeled out without any slack. If tethered robots become widespread, they will be small and capable of safely moving over a wide area. We believe that such robots can be used for many purposes, not just for solar panel maintenance, but also for cleaning buildings and inspecting high places. This will not only enable a sustainable supply of clean energy, but is also expected to have benefits such as reducing labor costs, preventing personal injury accidents, and improving work efficiency. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic diagram of a robot equipped with a tether reel mechanism for driving a robot, according to one embodiment of the present invention. [Figure 2] 1 is a schematic diagram of a reel device according to an embodiment of the present invention; [Figure 3] 1 shows a reel device according to an embodiment of the present invention when the tension of the tether is equal to or greater than a certain value. [Figure 4]1 shows a reel device according to an embodiment of the present invention when the tension of the tether is less than a certain value. [Figure 5] 1 is a schematic diagram illustrating a fastener interface of a reel device according to one embodiment of the present invention. [Figure 6] 1 is a schematic diagram showing an attitude determination jig for a reel device according to an embodiment of the present invention; [Figure 7] Schematic diagram of the outer cylinder (attitude determination fixture component) of one embodiment of the present invention. [Figure 8] 1 is a schematic diagram showing the inner cylinder (attitude determination fixture component) of one embodiment of the present invention. [Figure 9] FIG. 4 is a schematic diagram showing an example of a slack detection mechanism other than that shown in FIG. 3 according to an embodiment of the present invention. [Figure 10] 1 is a schematic diagram showing a reel device, an attitude determination jig, and a control unit according to an embodiment of the present invention. [Figure 11] Schematic diagram showing movement of an embodiment of the present invention to another cleaning target. [Figure 12] FIG. 2 is a schematic diagram illustrating the operation of an attitude determination mechanism according to one embodiment of the present invention. [Figure 13] FIG. 6 is a schematic diagram showing the operation of the attitude determination mechanism when 620a is about to contact the apex of 611a in one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] Description of the invention's structure

[0009] The robot of the present invention will be described with reference to Figure 1. Robot 1 is equipped with reeling devices 10 (A, B, C, D) and moves over the top surface of an object to be cleaned (a solar panel in this case). As shown in Figure 1, each reeling device 10 is equipped with a take-up pulley 100, a pay-out pulley 200, a slack detection mechanism 30, a hold-down hinge 500, an attitude determination mechanism 600, a tether 700, and a control unit 800.

[0010] [Control Unit] Based on the detection result of the slack detection mechanism 30, the control unit 800 controls the forward / reverse rotation of the electric motor connected to the winding pulley 100 and the unwinding pulley 200, and winds the tether 700 into or unwinds it from the reel device 10. The control unit 800 is connected to the electric motor and the switch unit 40 of the slack detection mechanism 30.

[0011] When the control unit 800 receives a signal from the slack detection mechanism 30 while the tether 700 is being unwound, The winding pulley 100 is stopped for a certain period of time. The slack is eliminated by rotating the payout pulley 200 in the payout direction, After the cancellation, the winding pulley 100 and the unwinding pulley 200 are controlled to rotate in the unwinding direction at the same speed.

[0012] Furthermore, when the control unit 800 receives a signal from the slack detection mechanism 30 while the tether 700 is being wound up, The payout pulley 200 stops for a certain period of time, The winding pulley 100 is rotated in the winding direction to eliminate the slack. After the tension is released, the winding pulley 100 and the supply pulley 200 are rotated in the winding direction at the same speed. The hinge 500 also holds down the tether 700 wound around the supply pulley 200, thereby preventing slack in the reel due to slack outside the reel.

[0013] [Slack detection mechanism] The slack detection mechanism 30 is a detection mechanism that detects slack in the tether 700 within the reel device 10 and sends the detection result to the control unit 800 in order to prevent tangling of the tether 700. The slack detection mechanism 30 includes a tension applying means 31, such as a spring-loaded hinge 300, that pulls the slack tether 700 and applies tension to the tether 700 above a certain value, and a switch unit 40, such as a limit switch 400, that detects the state when the tension applying means is below the certain value.

[0014] [Spring hinge (means for applying tension 31)] Spring hinge 300 is a mechanism that rotates around 300a, and tether 700 passes through pulley 300c. Spring 310 is hooked onto 300b, pulling the spring hinge toward limit switch 400. As a result, when there is no tension in tether 700, the force of the spring causes it to come into contact with limit switch 400.

[0015] In Figure 2, spring hinge 300 is shown as an example of means 31 for applying tension, but any means or mechanism that pulls slack tether 700 and applies tension to tether 700 above a certain value can be used. For example, as shown in Figure 9, a linearly moving elastic body such as a helical spring or rubber can be used. However, the spring hinge 300 is preferably used because it has a simple structure and is less prone to breakdowns and malfunctions.

[0016] [Limit switch (switch part 40)] The limit switch 400 is pressed by the spring hinge 300 to detect slack and send a signal to the control unit.

[0017] In addition, in Figure 2, a limit switch 400 is shown as an example of the switch section 40, but any method or device can be used as long as it can detect that the tension applying means 31 has fallen below a certain value. For example, as shown in Figure 9, a structure in which a sensor operating member 33 is provided on a helical spring 32 and the sensor operating member 33 operates the switch section 40, or a photo sensor, ultrasonic sensor, etc. may be used instead of the limit switch 400. Alternatively, a rotary encoder may be attached to the tension applying means 31 to detect slack based on the angle, or an ultrasonic sensor may be used to measure the distance from the tension applying means 31 to detect slack. However, the limit switch 400 is preferably used because it is easy to control. In particular, in the case of a reel device 10 for a cleaning robot for solar panels, using a limit switch 400 as the switch section 40 is preferable in terms of eliminating the risk of malfunction due to sunlight compared to a photosensor.

[0018] The operation of the slack detection mechanism 30 will be described with reference to Figures 3 and 4. Figure 3 is a diagram showing a state in which the tension of the tether 700 is higher than the force of the spring (tensioning means 31) and the tether 700 is not slack when the tether 700 is being wound and unwound. As shown in Figure 3, the spring-loaded hinge 300 rotates in a direction away from the limit switch 400 (OFF direction) due to the tension of the tether 700. Therefore, when the limit switch 400 is in the OFF state, it can be detected that the tether tension in the reel device 10 is sufficiently high.

[0019] 3 to the state shown in FIG. 4, when tether 700 is being wound and unwound, if the tether tension decreases, tether 700 becomes slack, and the force of the spring (tensioning means 31) becomes greater than the tension of tether 700, the spring force causes spring hinge 300 to rotate in a direction approaching limit switch 400 (ON direction), spring hinge 300 presses limit switch 400, limit switch 400 turns ON, and transmits a signal to control unit 800. This makes it possible to detect that the tether tension in reel device 10 is low.

[0020] [Attitude determination mechanism] As shown in Figures 2 and 10, the attitude determination mechanism 600 uniquely determines the attitude of the fixing device interface 620 at the tip of the tether when the reel device 10 has fully reeled in the tether 700, and is equipped with an attitude determination jig 610 and a fixing device interface 620.

[0021] [Attitude determination jig] The attitude determination jig 610 is a cylinder attached to the reel body 10 and includes an outer cylinder 611 and an inner cylinder 612. The slopes of both cylinders (slope 611a, slope 612a shown in FIGS. 7 and 8) are shaped to fit the protrusions (upper protrusion 620a, lower protrusion 620b) of the fixing device interface 620. Therefore, as shown in FIG. 12, when the fixing device interface 620 is pulled into the attitude determination jig 610 by winding the tether 700, the upper protrusion 620a of the fixing device interface slides along the slope 611a and fits into the recess 611b, as shown in the order of FIGS. 12(A) to 12(C), and the lower protrusion 620b is stored so that it avoids the slope 612a and hits the step surface 612b. As shown in Figure 13, when upper protrusion 620a tries to contact the vicinity of the apex of inclined surface 611a, lower protrusion 620b slides along inclined surface 612a, and upper protrusion 620a avoids the vicinity of the apex of inclined surface 611a (see Figure 13(A)), preventing the fastener interface from getting caught and becoming stuck. After that, upper protrusion 620a slides along inclined surface 611a (see Figures 13(B) and (C)), and the posture is uniquely determined. Lower protrusion 620b avoids inclined surface 612a and is stored so that it hits step surface 612b.

[0022] Outer Cylinder The outer cylinder 611 is an outer component of the attitude determination jig 610, and is structured so that its position is determined by a protrusion 620a on the top of the fixing device interface 620 fitting into a recess 611b at the bottom of the outer cylinder slope 611a.

[0023] Inner Cylinder The inner cylinder 612 is a complementary element of the outer cylinder 611 and is housed inside the outer cylinder 611 . When fixed fixture interface 620 is retracted into attitude determination jig 610, protrusion 620a at the top of fixed fixture interface 620 may hit the apex of inclined surface 611a, causing it to get stuck and making it impossible to determine the attitude. To prevent this, protrusion 620b at the bottom of fixed fixture interface 620 comes into contact with inclined surface 612a before protrusion 620a at the top of fixed fixture interface 620 reaches the apex of inclined surface 611a, thereby prioritizing the function of the inner cylinder and preventing it from getting stuck.

[0024] [Fixed fixture interface] The fixing device interface 620 is a device attached to the tip of the tether 700, and as shown in FIG. 10, with the fixing device 50 attached to the tip of the fixing device interface 620, it is a component that is fixed by hooking it onto the pole 20 of the object to be cleaned 2, as shown in FIG. As shown in FIG. 10, the tether 700 attached to the fixing device interface 620 passes through the inside of the outer cylinder 611 and the inner cylinder 612, and is wound around and let out by the payout pulley 200 and the take-up pulley 100. The fixed fixture interface 620 is a component that is fixed by, for example, hooking onto the pole 20 of the object to be cleaned 2 as shown in FIG. 1, with the fixed fixture 50 attached to the tip of the fixed fixture interface 620 as shown in FIG. 10. As shown in FIG. 10, the tether 700 attached to the fixing device interface 620 passes through the inside of the outer cylinder 611 and the inner cylinder 612, and is wound around and let out by the payout pulley 200 and the take-up pulley 100. The fixing device interface 620 has an upper protrusion 620a corresponding to the outer cylinder 611 and a lower protrusion 620b corresponding to the inner cylinder 612, and when the tether is wound up, it is pulled into the attitude determination jig and the protrusion 620a fits into the recess 611b of the outer cylinder 611, thereby uniquely determining the attitude.

[0025] [others] The reel mechanism 10 also includes a tether 700, a communication cable, and a power supply cable, which may be conventional. [Example]

[0026] 1 and 11, the movement of the robot 1 of the present invention when cleaning objects 2a and 2b (solar panels) and the operation of the reel device 10 will be described. The robot 1 is provided with four reel devices 10 (A, B, C, D), and by the operation of these four reel devices 10, it moves horizontally over the object to be cleaned 2 (solar panel). First, the fixtures 50 attached to the tips of the fixture interfaces 620 of the four reel devices 10 are fixed to the poles 20 (20Aa, 20Ba, 20Ca, 20Da) at the corners of the object to be cleaned 2a. In this state, for example, when the robot is moved in the direction of arrow A shown in Figure 1, reel devices 10A and 10B of the four reel devices 10 unwind and reel devices 10C and 10D retract, and while the robot 1 moves, a cleaning tool such as a cloth for cleaning the object to be cleaned 2 (not shown) cleans the surface of the object to be cleaned 2.

[0027] At this time, if slack occurs in the tether 700 when the reel device 10 is operating, the slack detection mechanism 30 detects the slack and sends a signal to the control unit 800. If slack occurs when the tether 700 is being unwound, the winding pulley 100 is stopped for a certain period of time and the unwinding pulley 200 is rotated in the unwinding direction to eliminate the slack, and normal operation is resumed (the winding pulley 100 and the unwinding pulley 200 rotate at the same speed). If slack occurs when the tether 700 is being wound up, the unwinding pulley 200 is stopped for a certain period of time and the winding pulley 100 is rotated in the winding direction to eliminate the slack, and normal operation is resumed. This is a mechanism that prevents malfunctions caused by tether 700 becoming tangled due to slack.

[0028] Next, the case where the robot 1 is moved to another object to be cleaned 2b after cleaning of the object to be cleaned 2a is completed, as shown in FIG. 11, will be described. The robot relocation arm 60, installed in the center of the robot 1, holds the fixture interface 620 and transfers the fixture 50 from the pole 20 to another pole 20. First, fixture 50D is removed from pole 20Da and transferred to pole 20Ab. Next, fixture 50C is transferred from pole 20Ca to pole 20Bb. Next, fixture 50A is transferred from pole 20Aa to pole 20Ea. Finally, fixture 50B is transferred from pole 20Ba to pole 20Fa. The dashed lines in Figure 11 indicate the positions of each fixture interface 620 and each tether 700 after transfer. This process of transferring the fixture interface 620 to the pole 20 to the right is repeated until the robot 1 has finally moved to the cleaning target 2b.

[0029] In this embodiment, the winding pulley 100 and the payout pulley 200 are stopped for a certain period of time to wind up the slack tether 700, but the control unit 800 may also be configured to wind up the slack tether 700 by controlling the winding pulley and the payout pulley to create a difference in the amount of winding or payout. However, a method in which the take-up pulley 100 and the delivery pulley 200 are stopped for a certain period of time is preferable in that it simplifies control. [Industrial Applicability]

[0030] The reel device of the present invention is not limited to use in moving a robot, but can also be applied to a device for winding up a tether (line), for example, an electric fishing reel. [Explanation of symbols]

[0031] 1. Robot 2. Cleaning items 2a Cleaning object a 2b Cleaning object b 10(A, B, C, D) Reel device 20 (Aa, Ba, Ca, Da, Ea, Fa, Ab, Bb) Paul 50(A, B, C, D) Fixtures 60 Robot movement arm 100 Winding pulley 200 Payout pulley 30 Slack detection mechanism 31 Means of applying tension 300 Spring Hinge 310 Spring 32 Helical spring 33 Sensor operating member 40 Switch section 400 limit switch 500 retaining hinge 600 Attitude determination mechanism 610 Attitude determination jig 611(a, b) Outer cylinder 612(a, b) Inner cylinder 620(a, b) Fixture Interface 700 Tether 800 control section

Claims

1. A reel device including a take-up pulley and a pay-out pulley for a tether used in a mobile robot, a control unit that detects slack in the reel and controls the electric motor; a slack detection mechanism that detects slack in the tether reel and sends the detected slack to the control unit; A reel device comprising:

2. the control unit is connected to the slack detection mechanism and the electric motor; 2. The reel device according to claim 1, wherein the forward / reverse rotation of the electric motor is controlled based on the detection result of the slack detection mechanism.

3. The slack detection mechanism is a detection mechanism that transmits a signal to a control unit when detecting slack that may cause tangling, a tensioning means actuated by variations in tether tension; a switch unit that is linked with the tension applying means; The reel device according to claim 1, further comprising:

4. The slack detection mechanism is mounted in a reel device, 4. The reel device according to claim 3, wherein a signal is sent to the control unit when slack is detected during winding and unwinding of the tether.

5. The slack detection mechanism has a spring hinge as a means for applying tension and a limit switch as a switch unit, and when the tension of the tether is equal to or greater than a certain value, the spring hinge rotates in a direction away from the limit switch, and the limit switch is not pressed down.

5. The reel device according to claim 4, wherein when the tension in the tether is less than a certain value, the spring-loaded hinge rotates in a direction approaching the limit switch, thereby pressing down the limit switch, thereby detecting slack in the tether.

6. When winding the tether, if the slack detection mechanism does not detect slack, the winding pulley and the unwinding pulley rotate at a constant speed, 4. The reel device according to claim 3, wherein when the slack detection mechanism detects slack, the winding pulley continues winding while the unwinding pulley stops for a certain period of time, thereby correcting the slack.

7. When the tether is being unwound, if the slack detection mechanism does not detect any slack, the winding pulley and unwinding pulley rotate at a constant speed.

4. The reel device according to claim 3, wherein when the slack detection mechanism detects slack, the winding pulley stops for a certain period of time while the unwinding pulley unwinds the line, thereby correcting the slack.

8. The reel device further includes an attitude determination mechanism for uniquely determining the attitude of the fixing device at the tip of the tether when the tether is completely wound up, and the attitude determination mechanism includes: an attitude determination jig; a fixture interface comprising a protrusion corresponding to the attitude determination jig; The reel device according to claim 1, further comprising:

9. 9. The reel device according to claim 8, wherein the attitude determining jig is comprised of an outer cylinder and an inner cylinder, and is attached to a tether outlet of the reel body.

10. 9. The reel device according to claim 8, wherein the fixing device interface is attached to the tip of the tether and has an upper protrusion corresponding to the outer cylinder of the attitude determination jig and a lower protrusion corresponding to the inner cylinder of the attitude determination jig.

11. 11. The reel device according to claim 10, wherein the attitude determination mechanism uniquely determines the attitude by causing the upper protrusion to slide along the slope of the outer cylinder and get into a recess in the outer cylinder when the fixing device interface is pulled into the attitude determination jig by the tether winding action of the reel mechanism, and when the upper protrusion reaches the top of the slope of the outer cylinder, the lower protrusion slides along the slope of the inner cylinder and changes direction, preventing the upper protrusion from getting caught on the slope of the outer cylinder.

12. A robot comprising the reel device according to any one of claims 1 to 11.

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