Actuator for wearable robot

Abstract

An actuator for a wearable robot according to the present invention is characterized by comprising: a motor; an input pulley connected to a rotary shaft of the motor and rotated by a rotational driving force of the motor; an output pulley which surrounds the motor and has a rotational axis line concentric with the input pulley, is arranged parallel along the rotational axis line, and in which the rotational driving force inputted to the input pulley is reduced and outputted; a driven pulley which is arranged to have a rotational axis line parallel to the rotational axis line of the input pulley and the output pulley, and which reduces a rotational motion force of the input pulley and transmits the rotational motion force to the output pulley; an input belt connecting the input pulley and the driven pulley and providing the rotational driving force of the input pulley to the driven pulley; and an output belt connecting the driven pulley and the output belt and providing the rotational driving force of the driven pulley to the output pulley.

Description

Actuators for wearable robots

[0001] The present invention relates to an actuator for a wearable robot, and more particularly, to an actuator for a wearable robot that drives a wearable robot.

[0002] Wearable robots, also known as exoskeletons, are robots that physically connect with humans to augment their capabilities. Depending on their structure, wearable robots can be categorized into upper-extremity robots (attached to the upper body, such as the shoulders and / or arms), lower-extremity robots (attached to the legs), and waist robots (attached to the waist). Furthermore, wearable robots are broadly categorized into military, industrial, and recycling robots based on their intended use.

[0003] Wearable robots are seeing a surge in research and development worldwide as their utility increases across various fields. A rapidly growing market for wearable robots is rehabilitation robots, which assist with rehabilitation treatment. These rehabilitation wearable robots are used as walking aids for lower extremities, and are equipped with small motors to provide the driving force needed to enable people with walking difficulties to walk more easily.

[0004] Meanwhile, wearable robots are largely comprised of hardware components such as sensors, controllers, reducers, and motors. Servo motors are primarily used, along with servo drives. Wearable motors are typically driven by the driving power of small motors.

[0005] However, since wearable robots operate using high-speed motors, they require a reducer to further control these high-speed motors. Reducers in wearable robots not only enhance stability and reliability, but also ensure smooth rotation of other components, extending their lifespan.

[0006] Specifically, the reason why a reducer is necessary to reduce motor speed in wearable robots is because reducing motor speed also reduces output (torque), requiring more power to restore the reduced output. Furthermore, directly reducing the motor can lead to overload between the motor and other components.

[0007] Therefore, the actuator structure having a motor and reducer used in a wearable robot needs to provide the output required by the design along with power reduction.

[0008] The purpose of the present invention is to provide an actuator for a wearable robot in which the structure of a motor and reducer used in the wearable robot is improved to improve the driving stability of the wearable robot and the efficiency of reverse driving of regenerative braking.

[0009] The solution to the above problem is achieved by an actuator for a wearable robot, characterized in that it includes a motor according to the present invention, an input pulley connected to a rotational axis of the motor and rotating by a rotational driving force of the motor, an output pulley having a rotational axis line concentric with the input pulley and arranged in parallel along the rotational axis line, and in which the rotational driving force input to the input pulley is reduced and output, a driven pulley having a rotational axis line parallel to the rotational axes of the input pulley and the output pulley, and in which the rotational motion of the input pulley is reduced and transmitted to the output pulley, an input belt interconnecting the input pulley and the driven pulley and providing the rotational driving force of the input pulley to the driven pulley, and an output belt interconnecting the driven pulley and the output belt and providing the rotational driving force of the driven pulley to the output pulley.

[0010] Here, the driven pulley may include a first driven pulley arranged on a side of the input pulley with a rotation axis parallel to the rotation axis of the input pulley and interconnected with the input belt, and a second driven pulley arranged on a side of the output pulley with a rotation axis parallel to the rotation axis of the output pulley and interconnected with the output belt.

[0011] It is preferable that the diameter of the first driven pulley is relatively larger than the diameter of the input pulley, and that the diameter of the second driven pulley is relatively smaller than the diameter of the output pulley.

[0012] It is preferable that the diameter of the above first driven pulley is relatively larger than the diameter of the above second driven pulley.

[0013] The reduction ratio of the input pulley and the output pulley can be set according to the ratio of the diameter of the second driven pulley and the diameter of the output pulley.

[0014] In addition, the actuator for the wearable robot may further include an idler arranged with a rotation axis parallel to the rotation axis of the output pulley and the second driven pulley, with the second driven pulley and the output belt interposed therebetween, to adjust the tension of the output belt.

[0015] The above-mentioned driven pulley can slide in the transverse direction of the rotational axes of the input pulley and the output pulley to adjust the tension of the input belt.

[0016] Meanwhile, the control unit may further be disposed parallel to the rotation axis of the input pulley and on the side of the input pulley to control the operation of the motor.

[0017] Specific details of other embodiments are included in the detailed description and drawings.

[0018] The effects of the actuator for a wearable robot according to the present invention are as follows.

[0019] First, by using a pulley structure having an input pulley, an output pulley, and a driven pulley, and a belt structure having an input belt connecting the input pulley and the driven pulley, and an output belt connecting the driven pulley and the output pulley, the rotational driving force provided from the motor can be precisely and accurately reduced, thereby improving the operational reliability of the wearable robot.

[0020] Second, by using a pulley structure having an input pulley, an output pulley, and a driven pulley, and a belt structure having an input belt connecting the input pulley and the driven pulley, and an output belt connecting the driven pulley and the output pulley, the regenerative braking efficiency can be improved, and accordingly, the energy usage of the battery can be increased, thereby increasing the operating time of the wearable robot.

[0021] FIG. 1 is a first operating plan view of an actuator for a wearable robot according to an embodiment of the present invention;

[0022] FIG. 2 is a side view of an actuator for a wearable robot according to an embodiment of the present invention illustrated in FIG. 1;

[0023] FIG. 3 is a rear view of an actuator for a wearable robot according to an embodiment of the present invention illustrated in FIG. 1;

[0024] Figure 4 is a second operating plan view of an actuator for a wearable robot according to an embodiment of the present invention.

[0025] FIG. 5 is a third operating plan view of an actuator for a wearable robot according to an embodiment of the present invention.

[0026] Hereinafter, an actuator for a wearable robot according to an embodiment of the present invention will be described in detail with reference to the attached drawings.

[0027] FIG. 1 is a first operating plan view of an actuator for a wearable robot according to an embodiment of the present invention, FIG. 2 is a side view of an actuator for a wearable robot according to an embodiment of the present invention illustrated in FIG. 1, FIG. 3 is a rear view of an actuator for a wearable robot according to an embodiment of the present invention illustrated in FIG. 1, FIG. 4 is a second operating plan view of an actuator for a wearable robot according to an embodiment of the present invention, and FIG. 5 is a third operating plan view of an actuator for a wearable robot according to an embodiment of the present invention.

[0028] As illustrated in FIGS. 1 to 5, an actuator (1) for a wearable robot according to an embodiment of the present invention includes a motor (30), an input pulley (50), an output pulley (70), a driven pulley (90), an input belt (110), and an output belt (130). In addition, the actuator (1) for a wearable robot according to an embodiment of the present invention further includes a frame (10), a bearing (80), a control unit (150), and an idler (170). The actuator (1) for a wearable robot according to an embodiment of the present invention operates by power provided from a battery (not shown). In addition, the actuator (1) for a wearable robot according to an embodiment of the present invention requires battery charging through regenerative braking to increase the usage time, and thus, the reverse driving must be smooth to improve efficiency during reverse driving.

[0029] The frame (10) supports a motor (30), an input pulley (50), an output pulley (70), and a driven pulley (90). In addition, the frame (10) also supports a control unit (150). The motor (30) is mainly a servo motor, but various motors such as a BLDC motor can be used.

[0030] The input pulley (50) is connected to the rotational axis of the motor (30) and rotates by the rotational driving force of the motor (30). In practice, the input pulley (50) directly rotates according to the rotational driving force of the motor (30) and provides a decelerating rotational motion force to the output pulley (70).

[0031] The output pulley (70) surrounds the motor (30) and has a rotation axis concentric with the input pulley (50) and is arranged parallel to the rotation axis. The output pulley (70) reduces and outputs the rotational driving force input to the input pulley (50). Here, the output pulley (70) is arranged in a stacked manner on top of the input pulley (50) as shown in the drawings, but is not limited thereto and may be arranged on the bottom of the input pulley (50).

[0032] The reduction ratio of the input pulley (50) and the output pulley (70) according to an embodiment of the present invention is set according to the diameter of the second driven pulley (94) and the diameter of the output pulley (70), which will be described later. In practice, the reduction ratio of the input pulley (50) and the output pulley (70) is preferably 20:1 as an embodiment of the present invention. However, the reduction ratio of the input pulley (50) and the output pulley (70) may vary other than 20:1 depending on design changes, the size of the motor (30), the torque of the motor (30), or the RPM range of the motor (30).

[0033] A bearing (80) is placed between the motor (30) and the output pulley (70). The bearing (80) reduces the frictional force between the motor (30) and the output pulley (70) when the output pulley (70) rotates based on the rotational force provided from the driven pulley (90) through the output belt (130).

[0034] The driven pulley (90) is arranged with a rotation axis parallel to the rotation axes of the input pulley (50) and the output pulley (70). The driven pulley (90) reduces the rotational motion of the input pulley (50) and transmits it to the output pulley (70). The driven pulley (90) is connected to the input pulley (50) by a mutual input belt (110) and is connected to the output pulley (70) by a mutual output belt (130). In one embodiment of the present invention, the driven pulley (90) includes a first driven pulley (92) and a second driven pulley (94).

[0035] The first driven pulley (92) is arranged on the side of the input pulley (50) with a rotation axis parallel to the rotation axis of the input pulley (50). The first driven pulley (92) is interconnected with the input belt (110). The first driven pulley (92) is spaced apart from the input pulley (50) so as to rotate with a rotation axis parallel to the rotation axis of the input pulley (50). The first driven pulley (92) is interconnected with the input pulley (50) by the input belt (110) and rotates according to the rotational force provided from the input pulley (50). For example, the first driven pulley (92) is connected to the input pulley (50) by the input belt (110) which is arranged in an endless track shape and rotates in the same direction as the input pulley (50).

[0036] The second driven pulley (94) is arranged on the side of the output pulley (70) with a rotation axis parallel to the rotation axis of the output pulley (70). The second driven pulley (94) is interconnected with the output belt (130). The second driven pulley (94) is spaced apart from the input pulley (50) so as to rotate with a rotation axis parallel to the rotation axis of the output pulley (70). The second driven pulley (94) is arranged above the first driven pulley (92), as shown in FIG. 2. Of course, the second driven pulley (94) may be arranged below the first driven pulley (92) when the output pulley (70) is arranged below the input pulley (50). The second driven pulley (94) is connected to the output pulley (70) by an output belt (130) arranged in an infinite track shape, and provides the rotational driving force provided from the first driven pulley (92), substantially the input belt (110), to the output pulley (70) in the same rotational direction.

[0037] In one embodiment of the present invention, the diameter of the first driven pulley (92) is relatively larger than the diameter of the input pulley (50), and the diameter of the second driven pulley (94) is relatively smaller than the diameter of the output pulley (70). In addition, the diameter of the first driven pulley (92) is relatively larger than the diameter of the second driven pulley (94). In this way, the reduction ratio is determined based on the sizes of the diameters of the first driven pulley (92) and the second driven pulley (94). For example, as described above with respect to the input pulley (50) and the output pulley (70), the reduction ratios of the input pulley (50) and the output pulley (70) are set based on the ratio of the diameters of the second driven pulley (94) and the diameters of the output pulley (70).

[0038] The input belt (110) interconnects the input pulley (50) and the driven pulley (90). The input belt (110) transmits the rotational driving force of the input pulley (50) to the driven pulley (90). Specifically, the input belt (110) interconnects the input pulley (50) and the first driven pulley (92).

[0039] The output belt (130) interconnects the driven pulley (90) and the output belt (130). The output belt (130) provides the rotational driving force of the driven pulley (90) to the output pulley (70). Specifically, the output belt (130) interconnects the second driven pulley (94) and the output pulley (70), and provides the rotational driving force of the second driven pulley (94) to the output pulley (70). More specifically, the output belt (130) provides the rotational driving force of the second driven pulley (94), which is linked with the same rotational axis as the first driven pulley (92), to the output pulley (70) after the rotational driving force of the input pulley (50) is transmitted to the first driven pulley (92) by the input belt (110).

[0040] The control unit (150) is arranged parallel to the rotation axis of the input pulley (50) and on the side of the input pulley (50) to control the operation of the motor (30). As illustrated in FIGS. 2 and 3, the control unit (150) is arranged on the side of the input pulley (50) so as to be included within the height range of the input pulley (50) and the length range of the frame (10). As the control unit (150) is arranged within the height range of the input pulley (50) and the length range of the frame (10), the size of the actuator (1) for a wearable robot according to an embodiment of the present invention can be relatively further reduced.

[0041] The idler (170) is arranged with a rotation axis parallel to the rotation axes of the output pulley (70) and the second driven pulley (94) with the second driven pulley (94) and the output belt (130) interposed therebetween. The idler (170) is substantially in contact with the output belt (130) and adjusts the tension of the output belt (130) moving along the circumferential direction of the second driven pulley (94) and the output belt (130).

[0042] On the other hand, the tension of the input belt (110) is adjusted according to the movement of the driven pulley (90). For example, as shown in FIGS. 4 and 5, when the driven pulley (90) moves left and right in a direction parallel to the rotational axes of the input pulley (50) and the output pulley (70), the tension of the input belt (110) interconnecting the input pulley (50) and the first driven pulley (92) is adjusted. Of course, when the tension of the input belt (110) is adjusted according to the movement of the driven pulley (90), the tension of the output belt (130) is also affected.

[0043] Accordingly, by using a pulley structure having an input pulley, an output pulley, and a driven pulley, and a belt structure having an input belt connecting the input pulley and the driven pulley, and an output belt connecting the driven pulley and the output pulley, the rotational driving force provided from the motor can be precisely and accurately reduced, thereby improving the operational reliability of the wearable robot.

[0044] In addition, by using a pulley structure having an input pulley, an output pulley, and a driven pulley, and a belt structure having an input belt connecting the input pulley and the driven pulley, and an output belt connecting the driven pulley and the output pulley, the regenerative braking efficiency can be improved, and accordingly, the energy usage of the battery can be increased, thereby increasing the operating time of the wearable robot.

[0045] Although the embodiments of the present invention have been described with reference to the attached drawings, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features thereof. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention.

[0046] [National Research and Development Project Supporting This Invention]

[0047] [Project ID] 1415184238, [Project Number] 20019022, [Ministry] Ministry of Trade, Industry and Energy, [Research Management Agency] Korea Institute of Industrial Technology Evaluation and Planning, [Research Project Name] Industrial Technology Innovation Project (Materials and Components Technology Development Project), [Research Project Name] Development of Customized Manufacturing Technology for Core Force and Torque Sensors for Service Robots, [Contribution Ratio] 1 / 1, [Organization] Adin Robotics, [Research Period] August 1, 2022 - December 31, 2024 (29 months)

Claims

1. Motor and; An input pulley connected to the rotational axis of the motor and rotated by the rotational driving force of the motor; An output pulley having a rotation axis that surrounds the motor and is concentric with the input pulley and is arranged parallel to the rotation axis, and the rotational driving force input to the input pulley is reduced and output; A driven pulley arranged with a rotation axis parallel to the rotation axes of the input pulley and the output pulley, and which reduces the rotational motion of the input pulley and transmits it to the output pulley; An input belt that interconnects the input pulley and the driven pulley and provides rotational driving force of the input pulley to the driven pulley; An actuator for a wearable robot, characterized in that it includes an output belt that interconnects the driven pulley and the output belt and provides the rotational driving force of the driven pulley to the output pulley.

2. In paragraph 1, The above-mentioned pulley is released, A first driven pulley arranged on the side of the input pulley with a rotation axis parallel to the rotation axis of the input pulley and interconnected with the input belt; An actuator for a wearable robot, characterized in that it includes a second driven pulley arranged on the side of the output pulley with a rotation axis parallel to the rotation axis of the output pulley and interconnected with the output belt.

3. In paragraph 2, The diameter of the above first-order pulley is relatively larger than the diameter of the above input pulley, An actuator for a wearable robot, characterized in that the diameter of the second driven pulley is relatively smaller than the diameter of the output pulley.

4. In paragraph 1, An actuator for a wearable robot, characterized in that the diameter of the first driven pulley is relatively larger than the diameter of the second driven pulley.

5. In paragraph 2, An actuator for a wearable robot, characterized in that the diameter of the first driven pulley is relatively larger than the diameter of the second driven pulley.

6. In paragraph 2, An actuator for a wearable robot, characterized in that the reduction ratio of the input pulley and the output pulley is set according to the ratio of the diameter of the second driven pulley and the diameter of the output pulley.

7. In paragraph 2, The actuator for the above wearable robot is, An actuator for a wearable robot, characterized in that it further includes an idler arranged with a rotation axis parallel to the rotation axis of the output pulley and the second driven pulley, with the second driven pulley and the output belt interposed therebetween, to adjust the tension of the output belt.

8. In paragraph 1, An actuator for a wearable robot, characterized in that the driven pulley slides in the transverse direction of the rotational axis of the input pulley and the output belt to adjust the tension of the input belt.

9. In paragraph 2, An actuator for a wearable robot, characterized in that the driven pulley slides in the transverse direction of the rotational axis of the input pulley and the output belt to adjust the tension of the input belt.

10. In paragraph 1, An actuator for a wearable robot, characterized in that it further includes a control unit that controls the operation of the motor and is arranged parallel to the rotation axis of the input pulley and on the side of the input pulley.

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