JP2022091462A - Wearable robot - Google Patents

Abstract

To provide a wearable robot suppressing reduction in stability of a human body.SOLUTION: A wearable robot includes: a multi-joint arm worn on a human body; a sensor detecting a posture of the multi-joint arm; and a control device correcting a tip end position of the multi-joint arm. The control device determines whether the human body swings on the basis of the detection result by the sensor, estimates a degree of influence on the human body by correction to the tip end position of the multi-joint arm when determined that the human body swings, and performs the correction to the tip end position of the multi-joint arm when the estimated degree of influence is smaller than a specified value.SELECTED DRAWING: Figure 1

Description

The present invention relates to a wearable robot.

In recent years, with the declining birthrate and aging population, efforts are being made to reduce the burden on humans by introducing robots at construction sites as well. For example, Patent Document 1 discloses a screw driving robot and a ceiling panel transfer robot for constructing a ceiling panel. Further, Patent Document 2 discloses a robot device that is configured by attaching an articulated arm to a trolley-type mobile robot and performs interior work such as screwing a ceiling panel.

Japanese Unexamined Patent Publication No. 2012-11653 Japanese Unexamined Patent Publication No. 5-321454

However, since various environments exist at the construction site, the conventional robot devices disclosed in Patent Document 1 and Patent Document 2 have difficult work. In addition, at construction sites, it is effective to enable humans and robots to coexist and collaborate in collaborative work and shared work in order to utilize robot devices. In order for humans and robots to cooperate, it is also effective to attach an arm-type robot to the human body.

When the robot is attached to the human body, the robot is displaced when the human body is tilted. Therefore, it becomes necessary to correct the posture of the robot according to the inclination of the human body. When the correction amount of the posture of the robot is relatively large, the change in the movement of the robot becomes relatively large. Therefore, the force acting on the human body becomes relatively large, and the stability of the human body decreases.

The present invention solves the above-mentioned problems, and an object of the present invention is to suppress a decrease in the stability of the human body in a wearable robot.

In order to achieve the above object, the wearable robot of the present invention includes an articulated arm mounted on a human body, a sensor for detecting the posture of the articulated arm, and a control device for correcting the tip position of the articulated arm. The control device determines whether or not the human body has swung based on the detection result of the sensor, and if it is determined that the human body has swung, the correction of the tip position of the articulated arm gives the human body. The degree of influence is estimated, and if the estimated degree of influence is smaller than a predetermined value, the tip position of the articulated arm is corrected.

According to the wearable robot of the present invention, it is possible to suppress a decrease in the stability of the human body.

Schematic diagram of the wearable robot according to the first embodiment of the present invention. Block diagram of a wearable robot The figure which shows the state which the human body is tilted in the wearable robot shown in FIG. Flowchart of the program executed by the controller Block diagram of the wearable robot according to the second embodiment of the present invention Partially enlarged view of the articulated arm Partially enlarged view of the articulated arm Flowchart of the program executed by the controller

<First Embodiment>
Hereinafter, the wearable robot according to the first embodiment of the present invention will be described with reference to the drawings. Hereinafter, the upper side and the lower side in FIG. 1 will be described as the upper side and the lower side of the wearable robot 1, respectively.

The wearable robot 1 is a robot that works in collaboration with a human. As shown in FIG. 1, the wearable robot 1 includes a mounting portion 10, an articulated arm 20, a sensor 30, a camera 40, and a control device 50.

The mounting portion 10 is for fixing the articulated arm 20 to the human body H of the user. The mounting portion 10 is configured to be removable from the human body H. The mounting portion 10 includes a backpack portion 11 and a plurality of belts 12. The backrest portion 11 is formed in a rectangular parallelepiped shape and is attached by being carried on the human body H. The plurality of belts 12 fix the backrest portion 11 to the human body H. In the present embodiment, the number of belts 12 is two, but it goes without saying that the number of belts 12 is not limited to this. An articulated arm 20 is attached to the upper side of the backrest portion 11.

The articulated arm 20 is a manipulator. The articulated arm 20 includes a base 21, a plurality of links 22, 23, 24, a plurality of joint portions J, a hand 25, a plurality of drive units M, and a plurality of angle detection units E.

It is needless to say that the number of joint portions J shown in FIG. 1 is four, and the number of drive portions M and the number of angle detection portions E are five, but the number is not limited to these. In the present embodiment, each of the first to third joint portions J1 to J3 has one axis. Further, the fourth joint portion J4 has two axes orthogonal to each other. Therefore, although the articulated arm 20 has five degrees of freedom, it goes without saying that the degree of freedom is not limited to this.

The base 21 is attached to the upper surface of the backpack portion 11. The first end of the first link 22 is connected to the base 21 via the first joint J1. The first joint portion J1 operates so as to rotate the first link 22 around one axis with respect to the base 21.

The first end of the second link 23 is connected to the second end of the first link 22 via the second joint J2. The second joint portion J2 operates so as to rotate the second link 23 about one axis with respect to the first link 22.

The first end of the third link 24 is connected to the second end of the second link 23 via the third joint J3. The third joint portion J3 operates so as to rotate the third link 24 about one axis with respect to the second link 23.

A hand 25 is connected to the second end of the third link 24 via a fourth joint J4. The fourth joint J4 operates so as to rotate the hand 25 about two axes orthogonal to each other with respect to the third link 24.

The hand 25 grips the work of the target work. The desired work is, for example, the work of lifting a ceiling panel at a construction site. The work is, for example, a ceiling panel.

The plurality of drive units M are arranged in each joint portion J, and a member connected to each joint portion J is rotated about an axis. The plurality of drive units M are controlled by the control device 50, and each joint unit J and thus the articulated arm 20 are operated. The drive unit M is, for example, a motor.

The plurality of angle detection units E are arranged in each drive unit M, and detect the rotation angle of each drive unit M. The rotation angle of each drive unit M corresponds to the joint angle of each joint unit J.

The sensor 30 is arranged on the base 21 and detects the posture of the articulated arm 20. The posture of the articulated arm 20 is an angle with respect to the vertical direction of the articulated arm 20, specifically, at an angle C at which the base 21 is tilted with respect to the vertical direction with the reference point P arranged on the base 21 as the origin. There is (Fig. 3). The sensor 30 detects the amount of change in the angle in a unit time, that is, the angular velocity. The sensor 30 is, for example, a gyro sensor. The sensor 30 may be a gravity sensor, that is, an acceleration sensor that detects an angle with respect to the vertical direction. The detection result of the sensor 30 is transmitted to the control device 50.

The camera 40 is arranged on the base 21 and acquires an image of a work place where a target work is performed. The image acquired by the camera 40 is transmitted to the control device 50.

The control device 50 is a computer that controls the wearable robot 1 in an integrated manner. The control device 50 controls the operation of the articulated arm 20. Further, as described later, the control of the operation of the articulated arm 20 is to correct the tip position of the articulated arm 20 according to the change in the posture of the articulated arm 20 caused by the swing of the human body H. include. The tip position of the articulated arm 20 is the position of the hand 25 as seen from the reference point P. Hereinafter, the position of the tip of the articulated arm 20 may be referred to as the position of the hand 25.

The swing of the human body H is that the human body H swings or tilts. The correction of the tip position of the articulated arm 20 is to bring the tip position of the articulated arm 20 moved by the swing of the human body H closer to the position before the swing of the human body H.

In the present embodiment, the correction of the tip position of the articulated arm 20 is executed when the articulated arm 20 is not operating. The case where the articulated arm 20 is not operating is a case where each of the plurality of joint portions J is not rotating. When the articulated arm 20 is not operating, for example, when the hand 25 grips the work for the wearable robot 1 to perform the desired work and the human body H is not moving, the hand 25 and thus the work Is stationary. That is, when the human body H swings while the hand 25 is stationary because the articulated arm 20 is not operating, and the tip position of the articulated arm 20 is corrected, the hand 25 is moved. The articulated arm 20 operates so as to remain stationary.

As shown in FIG. 2, the control device 50 includes an input unit 51, an angle calculation unit 52, a swing determination unit 53, a correction angle calculation unit 54, an influence degree estimation unit 55, a correction execution determination unit 56, and an orbit generation unit 57. It includes a target angle generation unit 58, a target angle addition unit 59, an angle error calculation unit 60, and an output unit 61. The control device 50 is composed of a processor that executes dedicated hardware or software. That is, by executing a predetermined program stored in advance in the storage area (not shown) of the control device 50, the control device 50 has an angle calculation unit 52, a swing determination unit 53, a correction angle calculation unit 54, and an influence. It functions as a degree estimation unit 55, a correction execution determination unit 56, a trajectory generation unit 57, a target angle generation unit 58, a target angle addition unit 59, an angle error calculation unit 60, and an output unit 61.

The input unit 51 acquires the detection result of the sensor 30 and the detection result of the angle detection unit E. The detection result of the angle detection unit E is stored in the storage area of the control device 50 in chronological order.

The angle calculation unit 52 calculates the current angle of the articulated arm 20. The current angle of the articulated arm 20 is the angle at which the base 21 of the articulated arm 20 is tilted with respect to the vertical direction (FIG. 3). Specifically, the angle calculation unit 52 acquires the angular velocity detected by the sensor 30 from the input unit 51 and integrates the acquired angular velocity to calculate the current angle of the articulated arm 20.

The swing determination unit 53 determines whether or not the human body H has swung when the articulated arm 20 is not operating. The swing determination unit 53 compares the detection result of the angle detection unit E acquired this time with the detection result of the angle detection unit E stored in the storage area and acquired last time. When both detection results are changed, the swing determination unit 53 determines that the articulated arm 20 is operating. When the swing determination unit 53 determines that the articulated arm 20 is operating, the swing determination unit 53 transmits the correction angle calculation unit 54 with the current angle of the articulated arm 20 as zero.

On the other hand, when the detection result of the angle detection unit E acquired this time is compared with the detection result of the angle detection unit E stored in the storage area and acquired last time, and the detection result has not changed, the swing determination unit 53 determines. It is determined that the articulated arm 20 is not operating. The swing determination unit 53 compares the detection result of the angle detection unit E acquired this time with the detection results of the plurality of angle detection units E stored in the storage area and acquired up to the previous time, and the articulated arm 20 May be determined whether or not is not working.

When the swing determination unit 53 determines that the articulated arm 20 is not operating, the angular velocity transmitted from the sensor 30 via the input unit 51 and the articulated arm 20 transmitted from the angle calculation unit 52. Get the current angle. When the acquired angular velocity is smaller than the predetermined angular velocity, the swing determination unit 53 determines that the human body H is not swinging. When the swing determination unit 53 determines that the human body H is not swinging, the swing determination unit 53 transmits the correction angle calculation unit 54 with the current angle of the articulated arm 20 as zero.

On the other hand, when the acquired angular velocity is equal to or higher than the predetermined angular velocity, the swing determination unit 53 determines that the human body H has swung. When the swing determination unit 53 determines that the human body H has rocked, the swing determination unit 53 transmits the acquired current angle of the articulated arm 20 to the correction angle calculation unit 54.

The correction angle calculation unit 54 calculates a correction angle for correcting the joint angle of each joint portion J in order to correct the tip position of the articulated arm 20 in response to the swing of the human body H.

When the correction angle calculation unit 54 acquires zero from the swing determination unit 53, the correction angle calculation unit 54 sets the correction angle to zero and transmits it to the influence degree estimation unit 55. When the correction angle is zero, the joint angle of each joint portion J is not corrected, so that the tip position of the multi-joint arm 20 is not corrected. When the correction angle calculation unit 54 transmits with the correction angle set to zero, the swing determination unit 53 determines that the articulated arm 20 is operating, or the articulated arm 20 is not operating. This is a case where it is sometimes determined that the human body H is not swinging. Therefore, if it is determined that the articulated arm 20 is operating, or if the human body H is not swinging when the articulated arm 20 is not operating, the tip position of the articulated arm 20 is corrected. Not done.

On the other hand, the correction angle calculation unit 54 obtains the current angle of the articulated arm 20 larger than zero from the swing determination unit 53, and the current joint unit from the angle detection unit E via the input unit 51. Obtain the joint angle of J. The correction angle calculation unit 54 calculates the position of the hand 25 when the human body H does not swing, based on the kinematics, using the acquired joint angles of the joint portions J.

Subsequently, the correction angle calculation unit 54 of each joint portion J required to position the hand 25 at the calculated position of the hand 25 when the human body H does not swing in the state where the human body H swings. The joint angle is calculated as the correction angle of each joint portion J. Specifically, the correction angle calculation unit 54 is based on inverse kinematics using the calculated position of the hand 25 when the human body H does not swing and the current angle of the acquired articulated arm 20. And calculate the correction angle.

Further, the correction angle calculation unit 54 calculates and calculates the difference between the calculated correction angle of each joint part J and the acquired current joint angle of each joint part J as the correction angle of each joint part J. The correction angle of each joint portion J is transmitted to the influence degree estimation unit 55.

The influence degree estimation unit 55 estimates the influence degree that the correction of the position of the hand 25 has on the human body H. Specifically, the influence degree estimation unit 55 corrects the joint angle of each joint portion J and the tip position of the multi-joint arm 20 by using the correction angle of each joint portion J acquired from the correction angle calculation unit 54. The force applied to the human body H in the above is estimated as the degree of influence. The degree of influence increases as the movement of the articulated arm 20 due to the correction and thus the force applied to the human body H increases. The relationship between the correction angle of each joint portion J and the degree of influence is actually measured by experiments or the like and derived in advance. The influence degree estimation unit 55 transmits the acquired correction angle and the estimated influence degree to the correction execution determination unit 56. When the influence degree estimation unit 55 acquires zero as the correction angle, the influence degree estimation unit 55 derives the influence degree to a value smaller than a predetermined value described later.

The correction execution determination unit 56 determines whether or not to correct the tip position of the articulated arm 20. The correction execution determination unit 56 determines that the correction of the tip position of the articulated arm 20 is executed when the acquired influence degree is smaller than the predetermined value, and transmits the acquired correction angle to the target angle addition unit 59. When the degree of influence is smaller than the predetermined value, the predetermined value is set so that the stability of the human body H is ensured even if the tip position of the articulated arm 20 is corrected.

On the other hand, when the degree of influence is equal to or higher than a predetermined value, when the tip position of the articulated arm 20 is corrected, a relatively large force acts on the human body H where the human body H is swinging. The stability of the human body H is reduced. Therefore, when the acquired degree of influence is equal to or higher than a predetermined value, it is determined that the correction of the tip position of the articulated arm 20 is not performed, and the correction angle is set to zero and transmitted to the target angle adding unit 59.

The trajectory generation unit 57 acquires the target position and the movement time of the hand 25 at a predetermined timing (for example, every predetermined time) when the power of the wearable robot 1 is turned on. The trajectory generation unit 57 is time-series data indicating the trajectory of the position of the hand 25 that moves from the current position to the target position in the movement time based on the current position of the hand 25 and the acquired movement time and the target position of the hand 25. To generate. The current position of the hand 25 is the target position of the hand 25 acquired last time. The trajectory generation unit 57 stores the acquired target position of the hand 25 in the storage area of the control device 50 in chronological order.

For example, when the wearable robot 1 is made to perform a target work, a target position of the hand 25 different from the previously input target position of the hand 25 is input in order to move the hand 25. When the target work is the work of lifting the ceiling panel, for example, the control device 50 controls the camera 40 by operating a switch (not shown) for setting the target position of the user, and the image of the ceiling for locating the ceiling panel. To get. The control device 50 performs predetermined image processing on the acquired image, and calculates a position for lifting the ceiling panel and thus a target position for the hand 25. The calculated target position of the hand 25 is acquired by the trajectory generation unit 57. Further, the movement time is calculated based on the calculated distance between the target position of the hand 25 and the current position of the hand 25, and is acquired by the trajectory generation unit 57.

On the other hand, when the control device 50 has not acquired the instruction to move the hand 25, the target position and the movement time of the hand 25 previously input are repeatedly input.

The trajectory generation unit 57 transmits the position of the hand 25 to the target angle generation unit 58 in order along the generated time series data from the current position of the hand 25 to the target position of the hand 25.

The target angle generation unit 58 generates a target angle for each joint portion J based on the inverse kinematics by using the position of the hand 25 acquired from the trajectory generation unit 57.

The target angle adding unit 59 adds the corrected correction angle of each acquired joint portion J to the generated target angle of each joint portion J.

The angle error calculation unit 60 acquires the joint angle of each current joint portion J from the angle detection unit E via the input unit 51, and adds the acquired current joint angle and the correction angle for each joint portion J. Calculate the difference from the target angle.

The output unit 61 calculates the target angular velocity for each drive unit M by using the difference between the joint units J calculated by the angle error calculation unit 60. The output unit 61 includes a PID compensator. That is, the output unit 61 calculates the target angular velocity so that the difference converges to zero by appropriately adjusting the three gains of proportionality, differentiation, and integration, which are diagonal matrices of constants. The output unit 61 outputs the calculated angular velocity as a control signal to each drive unit M.

Next, the program executed by the above-mentioned control device 50 and the operation of the wearable robot 1 when the program is executed will be described with reference to the flowchart shown in FIG. In this embodiment, the program is repeatedly executed when the power of the wearable robot 1 is turned on.

The swing determination unit 53 determines in S10 whether or not the human body H swings when the articulated arm 20 is not operating. When the angular velocity measured by the sensor 30 is smaller than the predetermined angular velocity because the human body H does not swing when the articulated arm is operating or when the articulated arm 20 is not operating (in S10). NO), the correction angle calculation unit 54 sets the correction angle to zero in S12 and advances the program to S16.

On the other hand, when the angular velocity measured by the sensor 30 is equal to or higher than the predetermined angular velocity due to the swing of the human body H when the articulated arm 20 is not operating (YES in S10), the correction angle calculation unit 54 determines. In S14, the correction angle is calculated.

Subsequently, the influence degree estimation unit 55 estimates the influence degree in S16. Further, the correction execution determination unit 56 determines in S18 whether or not the degree of influence is equal to or higher than a predetermined value. When the degree of influence is smaller than the predetermined value (NO in S18) due to the relatively small swing of the human body H, the correction execution determination unit 56 decides to execute the correction in S20 and ends the program. do.

When the correction is executed, the target angle addition unit 59 adds the correction angle to the target angle, and the output unit 61 outputs a control signal according to the target angle to the drive unit M of each joint unit J. Therefore, even if the human body H swings when the articulated arm 20 is not operating, the rotation angle of the drive unit M and the operation of the articulated arm 20 are corrected, so that the hand 25 is displaced from the target position. Can reach the suppressed position.

On the other hand, when the degree of influence is equal to or higher than a predetermined value due to the relatively large swing of the human body H (YES in S18), the correction execution determination unit 56 decides not to execute the correction in S22 and makes a program. To finish.

When the correction is not executed, the target angle addition unit 59 adds zero to the target angle, and the output unit 61 outputs a control signal according to the target angle to the drive unit M of each joint unit J. Therefore, the rotation angle of the drive unit M and thus the operation of the articulated arm 20 are not corrected, so that the stability of the human body H is ensured.

<Second Embodiment>
Next, the wearable robot 1 according to the second embodiment of the present invention will be described with reference to FIGS. 5 to 8 mainly with respect to a portion different from the above-described first embodiment. The control device 50 of the second embodiment further includes a drive limiting unit 162 and a position determination unit 163 (FIG. 5).

When the swing determination unit 53 determines that the human body H has swinged when the articulated arm 20 is not operating, the drive limiting unit 162 causes the movement of some of the joint parts J among the plurality of joint parts J. Restrict. Specifically, the drive limiting unit 162 limits the operation of a part of the joint portions J when the influence degree estimated by the influence degree estimation unit 55 is equal to or higher than a predetermined value.

Further, the drive limiting unit 162 determines the joint portion J that limits the movement according to a predetermined priority order. The predetermined priority order is defined so that the joint portion J arranged on the proximal end side of the articulated arm 20 is preferentially restricted over the joint portion J arranged on the distal end side of the articulated arm 20.

For example, when the movements of the first and second joint portions J1 and J2, which are the joint portions J arranged on the proximal end side of the articulated arm 20, are restricted, the correction of the motion of the articulated arm 20 is the third and fourth. The joints J3 and J4 of the above are operated. When the third and fourth joint portions J3 and J4 operate, the tip side from the third joint portion J3 in the multi-joint arm 20 operates (FIG. 6). In FIG. 6, the articulated arm 20 before the operation is shown by a broken line, and the articulated arm 20 after the operation is shown by a solid line.

On the other hand, when the movements of the third and fourth joint portions J3 and J4, which are the joint portions J arranged on the tip side of the articulated arm 20, are restricted, the correction of the operation of the articulated arm 20 is the first. , 2 joints J1 and J2 are operated. When the first and second joint portions J1 and J2 operate, the proximal end side operates from the third joint portion J3 in the multi-joint arm 20 (FIG. 7). In FIG. 7, the articulated arm 20 before the operation is shown by a broken line, and the articulated arm 20 after the operation is shown by a solid line.

In FIGS. 6 and 7, the articulated arm 20 is operated from the state in which the hand 25 is opened upward as shown by the broken line to the state in which the hand 25 is opened upward in the right direction as shown by the solid line. In the case of making the articulated arm 20, the case where the proximal end side is operated from the third joint portion J3 in the articulated arm 20 is more than the case where the distal end side is operated from the third joint portion J3 in the articulated arm 20. The movement and the degree of influence are large. Therefore, in the predetermined priority order, the joint portion J arranged on the proximal end side of the articulated arm 20 rather than the joint portion J arranged on the distal end side of the articulated arm 20 so that the calculated degree of influence becomes smaller. Is stipulated to be prioritized and restricted.

Further, the correction angle calculation unit 54 of the second embodiment calculates a correction angle for correcting the joint angle of the joint portion J, which is the target of the movement, when the drive limiting unit 162 restricts the movement of a part of the joint portion J. do.

The position determination unit 163 allows the tip position of the articulated arm 20 to be within the permissible range when the drive limiting unit 162 corrects the tip position of the articulated arm 20 in a state where the operation of a part of the plurality of joints J is restricted. Determine if it is inside.

The position determination unit 163 calculates the distance between the tip position of the articulated arm 20 immediately before the swing of the human body H and the tip position of the articulated arm 20 corrected by the swing of the human body H. The tip position of the articulated arm 20 immediately before the human body H swings is the position of the current joint portion J when the human body H does not swing, that is, when the current angle of the articulated arm 20 is set to zero. It is a position calculated using the joint angle.

When the human body H swings, the tip of the articulated arm 20 moves a distance according to the swing angle of the human body H from the position immediately before the swing. Here, when the correction is applied, the tip of the articulated arm 20 approaches the position where the human body H was located immediately before swinging. That is, the tip position of the articulated arm 20 corrected by the swing of the human body H starts from the position where the tip of the multi-joint arm 20 is located due to the swing of the human body H, and each joint portion. This is the position where the tip of the articulated arm 20 moves by correcting the joint angle of J by using the correction angle. The position where the tip of the articulated arm 20 is located due to the swing of the human body H is calculated using the current angle of the articulated arm 20.

When the distance between the tip position of the articulated arm 20 immediately before the swing of the human body H and the tip position of the articulated arm 20 corrected by the swing of the human body H is equal to or less than a predetermined distance, the position determination unit 163 Determines that the tip position of the articulated arm 20 is within the permissible range.

On the other hand, when the distance between the tip position of the articulated arm 20 immediately before the swing of the human body H and the tip position of the articulated arm 20 corrected by the swing of the human body H is larger than a predetermined distance, the position determination unit. 163 determines that the tip position of the articulated arm 20 is not within the permissible range.

Next, the program executed by the control device 50 of the second embodiment and the operation of the wearable robot 1 when the program is executed will be described with reference to the flowchart shown in FIG. In the second embodiment, the program is repeatedly executed when the wearable robot 1 is performing the desired work.

When the wearable robot 1 is performing the desired work, as described above, the target angular velocity is output as a control signal from the output unit 61 to the drive unit M of each joint portion J, and each joint portion J and thus the articulated joint. The arm 20 is operating and the hand 25 is moving toward the target position.

Note that S10 to S20 in the flowchart of FIG. 8 are the same as S10 to S20 in the flowchart of FIG. Therefore, it will be described from S30 of the flowchart of FIG.

When the degree of influence is equal to or higher than a predetermined value (YES in S18) due to the relatively large swing of the human body H, the drive limiting unit 162 limits the operation of a part of the joint portions J in S30. The drive limiting unit 162 limits the operation of one of the plurality of joint units J in the predetermined priority order. Specifically, the drive limiting unit 162 limits the operation of the first joint portion J1 located on the most proximal side of the articulated arm 20. The drive unit M that drives the joint portion J whose movement is restricted is not subject to control.

Subsequently, in S32, it is determined whether or not the number of drive units M to be controlled is one or more. When the operation of the first joint portion J1 is restricted, the drive unit M in the second to fourth joint portions J2 to J4 becomes the control target. Since one drive unit M is arranged in each of the second and third joint portions J2 and J3 and two drive units M are arranged in the fourth joint portion J4, the drive unit M to be controlled is There are four. In this case (YES in S32), the position determination unit 163 has the corrected tip position of the articulated arm 20 within the permissible range in the state where the movement of a part of the joint portions J is restricted in S34. Judge whether or not.

When the movement of a part of the plurality of joint portions J is restricted in the correction of the tip position of the articulated arm 20, the accuracy of the correction is lower than that in the case where the movement of a part of the joint portions J is not restricted. .. When the position of the hand 25 is not within the permissible range (NO in S34) due to a relatively large decrease in the accuracy of the correction, the correction execution determination unit 56 decides not to execute the correction in S36 and makes a program. Is finished.

On the other hand, when the position of the hand 25 is within the permissible range (YES in S34) because the decrease in the accuracy of the correction is relatively small, the influence estimation unit 55 is in S38 of the first joint portion J1. Re-estimate the degree of impact with restricted movement. Since the movement of the first joint portion J1 is restricted, the movement of the articulated arm 20 is smaller than that in the case where the movement of the joint portion J is not restricted. It is smaller than the degree of influence estimated in S16.

Subsequently, the correction execution determination unit 56 determines in S40 whether or not the re-estimated degree of influence is equal to or greater than a predetermined value. Since the decrease in the degree of influence is relatively large due to the restriction of the movement of the first joint portion J1, when the re-estimated degree of influence is smaller than the predetermined value (NO in S40), the correction execution determination unit 56 determines. The decision to execute the correction is made in S42, and the program ends.

On the other hand, since the decrease in the degree of influence is relatively small due to the restriction of the movement of the first joint portion J1, when the re-estimated degree of influence is equal to or higher than a predetermined value (YES in S40), the program is set. Return to S30.

In S30, the drive limiting unit 162 further restricts the operation of one of the plurality of joint units J by the drive limiting unit 162 in a predetermined priority order. Specifically, the drive limiting unit 162 limits the movement of the second joint portion J2 located on the most proximal side of the multi-joint arm 20 among the joint portions J whose movement is not restricted. Therefore, since the movements of the first and second joint portions J1 and J2 are restricted, the drive unit M in the third and fourth joint portions J3 and J4 is the control target.

Subsequently, S32 to 34 described above are executed with the movements of the first and second joint portions J1 and J2 restricted. When the tip position of the articulated arm 20 is within the permissible range (YES in S34), the influence estimation unit 55 is in a state where the movements of the first and second joint parts J1 and J2 are restricted in S38. Re-estimate the degree of impact.

Further, the correction execution determination unit 56 determines in S40 whether or not the degree of influence re-estimated in a state where the movements of the first and second joint portions J1 and J2 are restricted is equal to or higher than a predetermined value. When the re-estimated degree of influence is smaller than the predetermined value (NO in S40), the correction execution determination unit 56 determines to execute the correction in S42 and ends the program.

On the other hand, since the decrease in the degree of influence is relatively small due to the restriction of the movements of the first and second joints J1 and J2, the re-estimated degree of influence is equal to or higher than the predetermined value (YES in S40). , The program returns to S30.

In this way, the movement of one of the joint portions J among the plurality of joint portions J is restricted one by one according to a predetermined priority order (S30), and the tip position of the articulated arm 20 is within the permissible range (S34). If YES) and the re-estimated degree of influence becomes smaller than the predetermined value (NO in S40), the decision to execute the correction is made.

Further, in S30, when the number of drive units M to be controlled becomes zero by limiting the operation of all the joint portions J (NO in S32), the correction execution determination unit 56 is in S44. , Decides not to perform the correction and exits the program.

In this way, when the estimated degree of influence when all the joints J operate is equal to or higher than a predetermined value, the position of the hand 25 is corrected with the movement of a part of the plurality of joints J restricted. Since the degree of influence is estimated, the estimated degree of influence is suppressed. Therefore, it is possible to make a correction in which the degree of influence is suppressed.

Further, when the position of the hand 25 corrected in a state where the movement of a part of the plurality of joint portions J is restricted is within the allowable range, the correction is executed. Therefore, the deterioration of the correction accuracy is suppressed.

<Modification example>
The present invention is not limited to the embodiments described above. As long as it does not deviate from the gist of the present invention, a form in which various modifications are applied to the present embodiment and a form constructed by combining components in different embodiments are also included in the scope of the present invention.

For example, the degree of influence is the force applied to the human body H when the tip position of the articulated arm 20 is corrected, but instead, it is a moment applied to the human body H when the tip position of the articulated arm 20 is corrected. May be good. Further, the degree of influence may be derived based on the force and moment applied to the human body H when the tip position of the articulated arm 20 is corrected.

Further, the predetermined value may be different depending on the direction affecting the human body H when the tip position of the articulated arm 20 is corrected. The predetermined value may be set so that, for example, the force applied to the human body H when the tip position of the articulated arm 20 is corrected is smaller when it acts in the left-right direction than when it acts in the front-back direction. good.

Further, the predetermined value may be a different value depending on the magnitude of the swing of the human body H, that is, the angle calculated by the angle calculation unit 52. Specifically, the predetermined value may be set to decrease as the angle calculated by the angle calculation unit 52 increases.

Further, the correction of the tip position of the articulated arm 20 may be executed when the articulated arm 20 is operating. According to this, even when the articulated arm 20 is operating, if the estimated degree of influence is smaller than a predetermined value, the correction of the tip position of the articulated arm 20 is executed, so that the stability of the human body is achieved. Can be suppressed.

Further, the drive limiting unit 162 of the second embodiment restricts the operation of a part of the plurality of joint portions J in S30 when the degree of influence when all the joint portions J operate is equal to or higher than a predetermined value. However, instead of this, the degree of influence may be estimated by limiting the movement of a part of the plurality of joint portions J from the beginning.

Further, in the second embodiment, the control device 50 does not have to include the position determination unit 163. In this case, even when the position of the corrected hand 25 is not within the allowable range, if the degree of influence is smaller than the predetermined value, it is decided to execute the correction.

Further, the drive limiting unit 162 limits the joint portions J one by one, but the present invention is not limited to this, and the movements of a plurality of joint portions J may be restricted at one time.

Further, in the predetermined priority order, contrary to the above-mentioned order, the joint portion J arranged on the distal end side of the articulated arm 20 is prioritized over the joint portion J arranged on the proximal end side of the articulated arm 20. May be set to limit.

Further, the drive limiting unit 162 limits the movement of some joint portions J according to a predetermined priority order, but instead of this, the joint portion J that randomly restricts the movement without following the predetermined priority order. May be selected.

Further, although the drive unit M is a motor, the drive unit M may be a pneumatic actuator, a solenoid, or a linear motor instead of the motor, or may be configured by a combination thereof.

Further, the control device 50 may be a separate body from the wearable robot 1. In this case, the sensor 30, the camera 40, the drive unit M and the angle detection unit E of each joint portion J, and the control device 50 are communicably connected by wire or wirelessly. That is, the articulated arm 20 is remotely controlled by the control device 50. The control device 50 in this case may be, for example, a smartphone. In this case, the input unit 51 and the output unit 61 of the control device 50 form a “signal transmission / reception unit”.

The present invention can be widely used for wearable robots.

1 Mountable robot 10 Mounted part 20 Articulated arm 30 Sensor 50 Control device H Human body J Joint part

Claims (11)

The articulated arm attached to the human body and
A sensor that detects the posture of the articulated arm and
A control device for correcting the tip position of the articulated arm is provided.
The control device is
Based on the detection result of the sensor, it is determined whether or not the human body has shaken.
When it is determined that the human body has swung, the degree of influence of the correction of the tip position of the articulated arm on the human body is estimated.
If the estimated degree of influence is less than a predetermined value, the tip position of the articulated arm is corrected.
Wearable robot. The control device is
When it is determined that the human body has swung, the degree of influence of the correction of the tip position of the articulated arm in a state where the movement of a part of the plurality of joints of the articulated arm is restricted is determined. presume,
The wearable robot according to claim 1. The control device is
When the estimated degree of influence is equal to or greater than the predetermined value, the degree of influence that the correction of the tip position of the articulated arm in the state where the joint portion that restricts the movement is changed has on the human body is re-estimated.
If the re-estimated degree of influence is less than the predetermined value, the correction of the tip position of the articulated arm is performed.
The wearable robot according to claim 2. The control device is
The joints that limit the movement when estimating the degree of influence on the human body and the joints that limit the movement when re-estimating the degree of influence on the human body are determined according to a predetermined priority order.
The wearable robot according to claim 3. The predetermined priority order is set so as to preferentially limit the joint portion arranged on the proximal end side of the articulated arm over the joint portion arranged on the distal end side of the articulated arm.
The wearable robot according to claim 4. The control device is
The tip position of the articulated arm when the tip position of the articulated arm is corrected in a state where the movement of a part of the plurality of joints is restricted is calculated.
When the calculated tip position of the articulated arm is within the permissible range and the degree of influence is smaller than the predetermined value, the correction of the tip position of the articulated arm is executed.
The wearable robot according to any one of claims 2 to 5. The sensor is a gyro sensor.
The wearable robot according to any one of claims 1 to 6. The sensor is an acceleration sensor.
The wearable robot according to any one of claims 1 to 6. It is a program to correct the tip position of the articulated arm attached to the human body.
On the computer
The step of detecting the posture of the articulated arm and
A step of determining whether or not the human body has swung based on the detected posture of the articulated arm, and
When it is determined that the human body has swung, a step of estimating the degree of influence of the correction of the tip position of the articulated arm on the human body, and
When the estimated degree of influence is smaller than a predetermined value, the step of correcting the tip position of the articulated arm and the step of executing the step are executed.
program. It is a control method for correcting the tip position of the articulated arm attached to the human body.
The step of detecting the posture of the articulated arm and
A step of determining whether or not the human body has swung based on the detected posture of the articulated arm, and
When it is determined that the human body has swung, a step of estimating the degree of influence of the correction of the tip position of the articulated arm on the human body, and
Including a step of performing correction of the tip position of the articulated arm when the estimated degree of influence is less than a predetermined value.
Control method. A signal transmission / reception unit that receives the detection result of the sensor that detects the posture of the wearable robot mounted on the human body and transmits a control signal that causes the wearable robot to correct the tip position of the wearable robot.
A computer that generates the control signal is provided.
The computer
Based on the detection result of the sensor, it is determined whether or not the human body has shaken.
When it is determined that the human body has swung, the degree of influence of the correction of the tip position of the wearable robot on the human body is estimated.
If the estimated degree of influence is less than a predetermined value, the control signal is generated.
Control device.

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