Remote control input device

Abstract

The present invention comprises: a base arm (30); a movable arm (50) which is supported by the base arm (30) and is capable of moving relative to the base arm (30); a plurality of joints (J1, J2, J3, J4, J5) which connect arms constituting the base arm (30) and the movable arm (50) to other arms; an arm rest (81) which is attached to the movable arm (50) and on which the forearm of an operator is placed; and a signal output unit (120) which outputs an operation instruction signal in accordance with a movement of the arm rest (81) to operate a device to be operated. The movable arm (50) is a self-weight compensation type and comprises a variable torque damper (92) that is attached to at least one of the plurality of joints (J1, J2, J3, J4, J5); that comprises, on the inside thereof, a magnetic viscous fluid, and that changes a load torque arising when the joint (J1, J2, J3, J4, J5) rotates by changing a magnetic force applied to the magnetic fluid.

Description

Remote control input device Cross-reference to related applications

[0001] This application is based on Japanese Patent Application No. 2025-028273 filed with Japan on February 25, 2025, and the entire content of the base application is incorporated herein by reference.

[0002] The present invention relates to a remote control input device, and particularly to a remote control input device provided with a movable arm.

[0003] Patent Document 1 discloses a remote control input device. The remote control input device disclosed in Patent Document 1 includes an arm, and an operation unit is connected to a tip end of the arm. By operating the operation unit, an operated device located at a remote location is remotely controlled. Further, the remote control input device disclosed in Patent Document 1 includes a motor for providing haptic feedback that gives an operator operating the operation unit a sensation of operating the operated device located at a remote location.

[0004] Patent Document 2 discloses an arm support device. The arm support device disclosed in Patent Document 2 includes a self-weight compensating movable arm, and maintains a supporting force applied to an operator's arm at a constant value. The contents described in the prior art documents are incorporated herein by reference as a description of technical elements in this specification.

[0005] Japanese Unexamined Patent Application Publication No. 2021-94615 Japanese Unexamined Patent Application Publication No. 2015-171482

[0006] Remote control input devices are required to be light, easy to operate, and impose a small operation burden on humans. Further, it is desired to have a function of providing haptic feedback to an operator. On the other hand, in a remote control input device where an operator grips the operation unit by hand and performs an operation using the forearm, the self-weight of the arm is heavy. Therefore, the device disclosed in Patent Document 1 generates torque by a motor for haptic feedback. Since a motor can generate a relatively large torque, it can generate haptic feedback while supporting the self-weight of the arm.

[0007] However, when force feedback is provided by a motor, there is a problem in that it is difficult to control the arm to prevent it from moving uncontrollably due to runaway motor control. The reason why this control is difficult is explained below. The torque generated by the motor to support the arm's own weight is greater than the torque generated by the motor for force feedback. In other words, in order to provide appropriate force feedback, it is necessary to control small torque changes while a large torque is being generated to support the arm's own weight. Because such control is difficult, there is a problem in that it is difficult to control the arm to prevent it from moving uncontrollably, such as causing a person to be thrown around by the arm, due to runaway motor control.

[0008] This disclosure is made in light of these circumstances and aims to provide a remote control input device that can prevent the arm from moving due to a runaway control.

[0009] The above objectives are achieved by combinations of features described in the independent claims, and the subordinate claims provide further advantageous specific examples. The reference numerals in parentheses in the claims indicate a correspondence with specific embodiments described later as one aspect, and do not limit the scope of the disclosed technical information.

[0010] One disclosure to achieve the above objective is a remote control input device for remotely controlling a device to be operated, comprising: a base arm; a movable arm supported by the base arm and movable relative to the base arm; a plurality of joints connecting the arms constituting the base arm and the movable arm with other arms; an armrest attached to the movable arm on which the operator's forearm rests; and a signal output unit that outputs an operation instruction signal in accordance with the movement of the armrest in order to operate the device to be operated, wherein the movable arm is of the self-weight compensating type, and a variable torque damper attached to at least one of the plurality of joints, which contains a magnetoviscous fluid inside and changes the load torque when the joint rotates by changing the magnetic force applied to the magnetoviscous fluid.

[0011] This remote control input device has an armrest attached to a self-weight-compensating movable arm. Because it is self-weight-compensating, the operator can move the armrest attached to the movable arm with little force, even without a motor supporting the arm's own weight.

[0012] In addition, it is equipped with a variable torque damper that controls the load torque when the joint rotates. By controlling the load torque when the joint rotates, this variable torque damper can provide force feedback to the operator.

[0013] A variable torque damper changes the load torque by changing the magnetic force applied to the magnetic fluid. This type of variable torque damper cannot generate a load torque that is as large as that of a motor. Therefore, it was difficult to apply when it was necessary to support the weight of the arm itself. However, since the movable arm is a self-weight-compensating type, the variable torque damper does not need to support the weight of the movable arm. Therefore, a variable torque damper using magnetic fluid can be used. Furthermore, because it is a variable torque damper using magnetic fluid, unlike when the load torque is controlled by the reaction force of a motor, it can suppress the arm from moving due to a runaway control.

[0014] A diagram illustrating the schematic configuration of the remote control input device of the first embodiment. A view of the armrest from the direction of arrow A in Figure 1. A diagram illustrating the configuration of the joint unit. A diagram illustrating the weight of the counterweight.

[0015] <First Embodiment> (Overall Configuration) The embodiments will be described below based on the drawings. Figure 1 is a diagram illustrating the schematic configuration of the remote control input device 10 of the first embodiment. The remote control input device 10 is a device for remotely controlling a device to be controlled that is located at a distance. The remote control input device 10 is equipped with a trolley 20, on which a base arm 30 is fixed.

[0016] The trolley 20 comprises a plurality of wheels 21 and a flat base plate 22. The base arm 30 extends perpendicularly to the upper surface of the base plate 22. The base arm 30 comprises a lower base arm 31 and an upper base arm 32. One end of the lower base arm 31 is fixed to the base plate 22. The lower base arm 31 and the upper base arm 32 are connected via a joint J1. Because the upper base arm 32 is connected to the lower base arm 31 via the joint J1, it is rotatable relative to the lower base arm 31 around the axes of the lower base arm 31 and the upper base arm 32.

[0017] A movable arm 50 is attached to the tip of the base arm 30 via a joint J2. The base arm 30 supports the movable arm 50 so that it can move relative to the base arm 30. The joint J2 has a rotation axis in a direction perpendicular to the base arm 30, that is, in the horizontal direction when the remote control input device 10 is installed on a horizontal plane.

[0018] The movable arm 50 is equipped with a four-bar linkage mechanism 60. The four-bar linkage mechanism 60 consists of four links 61, 62, 63, and 64 connected in a closed loop by four joints J3a, J3b, J3c, and J3d. When the four joints J3a, J3b, J3c, and J3d are not distinguished, they are referred to as joint J3. The four links 61, 62, 63, and 64 are rod-shaped. Links 61 and 63 are parallel to each other, and links 62 and 64 are parallel to each other. Therefore, the four-bar linkage mechanism 60 is a parallel linkage mechanism.

[0019] Joint J2 is located rearward from the center of link 61. The four-bar linkage mechanism 60 rotates around the axis of rotation of joint J2. Link 62 extends in the opposite direction to joint J3b than joint J3a. The four-bar linkage mechanism 60 or link 61 can be considered as the first arm, and the portion of link 62 that protrudes from the four-bar linkage mechanism 60 can be called the second arm.

[0020] A joint J4 is fixed to the tip of link 62. Joint J4 has an axis oriented in the same direction as joint J3. One end of support arm 70 is connected to joint J4. Support arm 70 comprises a lower support arm 71 and an upper support arm 72. One end of the lower support arm 71 is connected to joint J4. The other end of the lower support arm 71 is connected to joint J5. Joint J5 has a rotation axis aligned with the direction in which the lower support arm 71 and upper support arm 72 extend.

[0021] An operating unit 80 is fixed to the tip of the upper support arm 72. The operating unit 80 is attached to the movable arm 50 via the support arm 70. The operating unit 80 is rotatable around the axes of the lower support arm 71 and the upper support arm 72.

[0022] The operating unit 80 comprises an armrest 81, a gripping body 82, and a connecting arm 83. The armrest 81 is the part on which the operator's forearm rests. Figure 2 is a view of the armrest 81 from the direction of arrow A in Figure 1. The armrest 81 is supported by a joint J6, and the joint J6 is fixed to an upper support arm 72. With this configuration, the armrest 81 rotates in the direction of the double arrows shown in Figure 2.

[0023] Let's return to the explanation in Figure 1. The gripping body 82 is the part that the operator grasps when operating the remote control input device 10. The connecting arm 83 is a rod-shaped body that connects the armrest 81 and the gripping body 82. The operator places their forearm on the armrest 81, grasps the gripping body 82 with their hand, and moves the gripping body 82 forward, backward, left, right, up, and down.

[0024] The joints J1, J2, J3, and J4 are each fitted with a joint unit 90 as shown in Figure 3. The joint unit 90 includes a brake 91, a variable torque damper 92, and a gear 93. The brake 91 generates sliding resistance against the rotation axis Ja of the joints J1, J2, J3, and J4. The brake 91 restricts the movement of the joints J1, J2, J3, and J4 by this sliding resistance. The brake 91 is released when energized and operates when de-energized. The type of brake 91 can be, for example, electromagnetic or non-energized.

[0025] The variable torque damper 92 is a type of damper that contains a magnetorheological fluid, and the sliding resistance changes by changing the magnetic force applied to the magnetorheological fluid. The magnetorheological fluid is also called an MR (Magneto-Rheological) fluid. The sliding resistance refers to the load torque of the variable torque damper 92. The variable torque damper 92 is connected to the rotating shaft Ja via a gear 93. When the load torque of the variable torque damper 92 changes, the load torque when the rotating shaft Ja rotates changes.

[0026] A joint unit, excluding the brake 91 and gear 93, is attached to joint J5. In this joint unit, the variable torque damper 92 is directly fixed to the rotation axis of joint J5. The reason why the variable torque damper 92 is attached to joints J1, J2, J3, J4, and J5 is to enable force feedback for all directions of movement of the operating unit 80. A joint unit 90 may also be attached to joint J5.

[0027] Let's return to the explanation in Figure 1. The remote control input device 10 is equipped with a first counterweight 111 and a second counterweight 112. These are weights used to make the movable arm 50 self-weight-compensated.

[0028] Link 64 extends in the opposite direction to joint J3d compared to joint J3c. The first counterweight 111 is fixed to the tip of link 64 that protrudes from the four-bar linkage mechanism 60. Link 61 extends in the opposite direction to joint J3a compared to joint J3d. The second counterweight 112 is fixed to the tip of link 61 that protrudes from the four-bar linkage mechanism 60.

[0029] The control device 120 is installed on the trolley 20. The control device 120 is electrically connected to the joint unit 90 and controls the brake 91 and the variable torque damper 92. The control device 120 changes the load torque of the variable torque damper 92 by PWM (Pulse Width Modulation) control.

[0030] The control device 120 is configured, for example, to include one or more processors and memory. The control device 120 receives a load determination signal from an external source to determine whether to increase or decrease the movement of the movable arm 50. The load determination signal is input from a monitoring device that monitors the operating state of the operated device. The operated device is, for example, a device equipped with an arm that performs work by moving the arm. The monitoring device, for example, inputs a load determination signal to increase the movement of the operating unit 80 when the arm of the operated device becomes difficult to move.

[0031] Based on this load determination signal, the control device 120 determines the load torque to be generated in each of the variable torque dampers 92 attached to joints J1, J2, J3, J4, and J5. Then, it generates the determined load torque in each of the variable torque dampers 92. This provides force feedback.

[0032] Furthermore, the control device 120 sequentially detects the position of the gripping body 82. For example, joints J1, J2, J3, J4, and J5 are each equipped with rotation angle sensors to detect the rotation angle, and the position of the gripping body 82 is sequentially detected based on the detected values ​​of the multiple rotation angle sensors.

[0033] The control device 120 then outputs an operation instruction signal to operate the device to be operated, according to the movement of the gripping body 82, which is determined from the detected change in the position of the gripping body 82. The relative position between the gripping body 82 and the armrest 81 is constant. Therefore, it can also be said that the operation instruction signal is a signal determined according to the movement of the armrest 81. Since it outputs this operation instruction signal, the control device 120 is a signal output unit.

[0034] (Weight of counterweights) The movable arm 50 is of the self-weight compensation type. The self-weight compensation type means a structure in which the effect of the movable arm 50's own weight on operation can be canceled out by a mechanical structure, that is, without electrical control. In order to be of the self-weight compensation type, the movable arm 50 of this embodiment is equipped with a first counterweight 111 and a second counterweight 112.

[0035] The weights of the first counterweight 111 and the second counterweight 112 will now be explained. The virtual plane VP shown in Figure 4 is a plane that includes the lower base arm 31, the upper base arm 32, and the axis of rotation of the joint J2. In other words, the virtual plane VP is a plane perpendicular to the plane that includes the four-bar linkage mechanism 60, and includes the lower base arm 31 and the upper base arm 32. The area on the gripping body 82 side of this virtual plane VP is defined as the front region Rf, and the area on the opposite side is defined as the rear region Rr.

[0036] The first counterweight 111 and the second counterweight 112 are located on opposite sides of the virtual plane VP. The weights of the first counterweight 111 and the second counterweight 112 are adjusted so that the weight of the portion supported by the joint J2 is equal in the front region Rf and the rear region Rr. As a result, the movable arm 50 becomes a self-weight compensating type.

[0037] In addition, the weights of the first counterweight 111 and the second counterweight 112 are adjusted so that an upward force is generated in the operating section 80, including the armrest 81. The weights of the first counterweight 111 and the second counterweight 112, which generate an upward force in the operating section 80, will now be explained.

[0038] Due to the structure in which the movable arm 50 is supported by the joint J2, the weight of the first counterweight 111 and the second counterweight 112, which are located below the joint J2, i.e., the vertically downward force, acts as an upward force on the operating part 80.

[0039] Therefore, the upward force generated in the operating section 80 can be adjusted by making the weight of the first counterweight 111 and the second counterweight 112 lighter or heavier, while ensuring that the weight of the part supported by joint J2 is equal in the front region Rf and the rear region Rr. The part supported by joint J2 is the part of the remote control input device 10 excluding the trolley 20 and the base arm 30.

[0040] In this embodiment, the weights of the first counterweight 111 and the second counterweight 112 are adjusted so that a slight upward force is generated in the operating section 80, for example, a small upward force of 1.0 kgf or less.

[0041] In the first embodiment of the remote control input device 10 described above, the operating unit 80 is attached to a self-weight-compensating movable arm 50. Because it is a self-weight-compensating type, even if the arm's own weight is not supported by a motor, the operator can move the arm rest 81 attached to the movable arm 50 with little force.

[0042] In addition, it is equipped with a variable torque damper 92 that controls the load torque when joints J1, J2, J3, J4, and J5 rotate. By controlling the load torque when joints J1, J2, J3, J4, and J5 rotate using this variable torque damper 92, force feedback can be provided to the operator.

[0043] The variable torque damper 92 changes the load torque by changing the magnetic force applied to the magnetic fluid. This type of variable torque damper cannot generate a load torque that is large compared to a motor. Therefore, it was difficult to apply when it was necessary to support the weight of the arm. However, since the movable arm 50 is a self-weight compensating type, the variable torque damper 92 does not need to support the weight of the movable arm 50. For this reason, a variable torque damper 92 using magnetic fluid can be used. Furthermore, because the variable torque damper 92 uses magnetic fluid, unlike when the load torque is controlled by the reaction force of a motor, it is possible to suppress the arm from moving due to unpredictable control malfunctions.

[0044] Furthermore, the movable arm 50 is equipped with a four-bar linkage mechanism 60, to which a first counterweight 111 and a second counterweight 112 are attached. The weights of the first counterweight 111 and the second counterweight 112 are adjusted to generate an upward force on the operating section 80. This upward force on the operating section 80 prevents the forearm from separating from the armrest 81, even without fixing the forearm to the armrest 81 with a band or the like.

[0045] The first counterweight 111 and the second counterweight 112 are located on opposite sides of a virtual plane VP that is perpendicular to the plane containing the four-bar linkage mechanism 60 and contains the base arm 30. In other words, the first counterweight 111 is located on the opposite side of the operation unit 80 with reference to the virtual plane VP, while the second counterweight 112 is located on the same side of the operation unit 80 with reference to the virtual plane VP.

[0046] Furthermore, when the operation unit 80 is located above the joint J2, the first counterweight 111 and the second counterweight 112 are located below the joint J2, and apply an upward force to the operation unit 80.

[0047] With this configuration, when an upward force is applied to the operation unit 80, the remote control input device 10 can reduce the horizontal dimension orthogonal to the virtual plane VP, compared to a case where both the first counterweight 111 and the second counterweight 112 are located on a different side from the operation unit 80 with reference to the virtual plane VP.

[0048] The load torque of the variable torque damper 92 is changed through PWM control performed by the control device 120. Since PWM control is adopted, the load torque can be easily changed by a small degree.

[0049] The embodiment has been described above. However, the disclosed technology is not limited to the above embodiment, the following modifications are also included within the disclosed scope, and various modifications can be further made and implemented without departing from the gist of the invention other than those described below.

[0050] <Modification 1> For example, both the first counterweight 111 and the second counterweight 112 may be located on a different side from the operation unit 80 with reference to the virtual plane VP. In this case, the horizontal dimension of the remote control input device becomes larger compared to the embodiment. However, similar to the embodiment, the movement of the arm caused by runaway control can be suppressed.

[0051] (Disclosure of Technical Ideas) This specification discloses several technical ideas as described in the following paragraphs. Some paragraphs may be written in a multiple dependent form, where subsequent paragraphs optionally refer to preceding paragraphs. Furthermore, some paragraphs may be written in a multiple dependent form, where they refer to other multiple dependent forms. These paragraphs written in multiple dependent forms define several technical ideas.

[0052] (Technical Concept 1) A remote control input device for remotely controlling a device to be operated, comprising: a base arm (30); a movable arm (50) supported by the base arm and movable relative to the base arm; a plurality of joints (J1, J2, J3, J4, J5) connecting the arms constituting the base arm and the movable arm to other arms; an armrest (81) attached to the movable arm on which the operator's forearm rests; and a signal output unit (120) that outputs an operation instruction signal in accordance with the movement of the armrest in order to operate the device to be operated, wherein the movable arm is of the self-weight compensating type, and a variable torque damper attached to at least one of the plurality of joints, which contains a magnetoviscous fluid inside and changes the load torque when the joint rotates by changing the magnetic force applied to the magnetoviscous fluid.

[0053] (Technical Concept 2) The movable arm comprises a four-bar linkage mechanism (60) in which four links are connected in a closed-loop manner by four joints, and the remote control input device comprises counterweights (111, 112) attached to the four-bar linkage mechanism, and the counterweights are heavy enough to generate an upward force on the armrest, as described in Technical Concept 1.

[0054] (Technical Concept 3) The remote control input device according to Technical Concept 2, comprising a first counterweight (111) and a second counterweight (112) as the counterweights, which are located on opposite sides of a virtual plane (VP) including the base arm, perpendicular to the plane including the four-bar linkage mechanism, wherein when the arm rest is above the position where the base arm supports the movable arm, the first counterweight and the second counterweight are located below the position where the base arm supports the movable arm.

[0055] (Technical Concept 4) A remote control input device according to any one of Technical Concepts 1 to 3, comprising a brake (91) attached to one or more of the joints and having a brake that restricts the movement of the joints.

[0056] (Technical Concept 5) The variable torque damper is controlled by PWM so that the load torque changes, as described in any one of Technical Concepts 1 to 4, and is a remote control input device.

Claims

1. A remote control input device for remotely controlling a device to be operated, comprising: a base arm (30); a movable arm (50) supported by the base arm and movable relative to the base arm; a plurality of joints (J1, J2, J3, J4, J5) connecting the arms constituting the base arm and the movable arm to other arms; an armrest (81) attached to the movable arm on which the operator's forearm rests; and a signal output unit (120) that outputs an operation instruction signal in accordance with the movement of the armrest in order to operate the device to be operated, wherein the movable arm is of a self-weight compensating type, and a variable torque damper attached to at least one of the plurality of joints, which contains a magnetoviscous fluid inside, and changes the load torque when the joint rotates by changing the magnetic force applied to the magnetoviscous fluid.

2. The movable arm comprises a four-bar linkage mechanism (60) in which four links are connected in a closed-loop manner by four joints, and the remote control input device comprises counterweights (111, 112) attached to the four-bar linkage mechanism, wherein the counterweights are heavy enough to generate an upward force on the armrest, as described in claim 1.

3. The remote control input device according to claim 2, comprising a first counterweight (111) and a second counterweight (112) as the counterweights, which are located on opposite sides of a virtual plane (VP) including the base arm, perpendicular to the plane including the four-bar linkage mechanism, wherein when the arm rest is above the position where the base arm supports the movable arm, the first counterweight and the second counterweight are located below the position where the base arm supports the movable arm.

4. A remote control input device according to any one of claims 1 to 3, comprising a brake (91) attached to one or more of the joints and having a limiting mechanism for the movement of the joints.

5. The remote control input device according to any one of claims 1 to 3, wherein the variable torque damper is PWM controlled so that the load torque changes.

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