US-12622835-B2 - Driving system and control method for hybrid gait rehabilitation robot

Abstract

A driving system of a hybrid gait rehabilitation robot include: a driving unit that is connected to a footrest of the gait rehabilitation robot and transmits a driving force such that the robot operates at a preset speed; a speed detection unit that detects a gait speed of an occupant; and a control unit that controls a speed of the driving unit by comparing the detected speed of the speed detection unit with a speed applied by the driving unit. The driving unit transmits power toward the occupant, but the driving force of the occupant is not transmitted to the driving unit.

Inventors

• JUNG YUP KIM
• Jung Joon Kim
• Hyeong Sic KIM
• Seon Deok EUN
• Do Hoon KOO
• Hyun Ju Park

Assignees

• FOUNDATION FOR RESEARCH AND BUSINESS, SEOUL NATIONAL UNIVERSITY OF SCIENCE AND TECHNOLOGY
• NATIONAL REHABILITATION CENTER

Dates

Publication Date

20260512

Application Date

20200915

Priority Date

20190927

Claims (4)

1. 1 . A driving system for a hybrid gait rehabilitation robot, the driving system comprising: a driving unit that is connected to a footrest of a gait rehabilitation robot and transmits a driving force so that the gait rehabilitation robot operates at a preset speed; a speed detection unit that detects a gait speed of an occupant; and a control unit that controls a speed of the driving unit by comparing the detected speed of the speed detection unit with a speed applied by the driving unit, wherein the driving unit transmits power to the occupant in a driving direction, but a driving force of the occupant in the driving direction is not transmitted to the driving unit, wherein the driving unit is driven according to a preset gait speed, and a speed of a motor is changed according to an angle of a crank, wherein the control unit determines the speed of the motor in consideration of a speed intention and an acceleration intention of the occupant, and wherein the control unit adjusts the speed of the motor by: applying a motor speed profile function based on a preset reference gait speed (a) corresponding to the angle of the crank (θc), and incorporating the difference between a target gait speed of the occupant (v walking ) and the preset reference gait speed (a) using a proportional constant between the gait speed and the motor speed, further, to reflect the occupant's speed intention, the control unit applies a speed intention gain (k v ) to the difference between the crank angle (θc) and a reference angle function (kg(θc)), and to reflect the occupant's acceleration intention, the control unit applies an acceleration intention gain (k a ) to the difference between the second derivative of the crank angle (θ″c) and the second derivative of the reference angle function (kg″(θc)), thereby finely adjusting the motor speed.
2. 2 . The driving system of claim 1 , wherein the speed detection unit detects the gait speed of the occupant by measuring an angular speed of the crank of a lower extremity mechanism connected to the footrest.
3. 3 . The driving system of claim 1 , wherein the driving unit transmits the power to a pair of footrests using one rotary shaft.
4. 4 . The driving system of claim 3 , wherein the driving unit includes a free wheel body, a decelerator, and a motor, and the free wheel body transmits a driving force of the motor in the driving direction to the footrest but prevents the driving force of the occupant in the driving direction from being transmitted from the free wheel body to the motor.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Section 371 of International Application No. PCT/KR2020/012406, filed Sep. 15, 2020, which was published in the Korean language on Apr. 1, 2021 under International Publication No. WO 2021/060759 A1, which claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2019-0119284, filed on Sep. 27, 2019 the disclosures of all of which are incorporated herein by reference in their entireties. TECHNICAL FIELD The present invention relates to a driving system and a control method for a hybrid gait rehabilitation robot. More specifically, the present invention relates to a driving system and a control method for a parallel hybrid gait rehabilitation robot that separates a gait force of a patient and a gait force of a robot. BACKGROUND ART In general, gait rehabilitation robots are robots used for rehabilitation treatment of patients of which movements are inconvenient due to causes such as lower extremity paralysis or decreased muscle strength. Due to the aging, patients having representative diseases of central nervous system diseases caused by cerebral strokes are rapidly increasing. Due to decreases in exercise abilities of lower extremities that frequently occur in these patients, it may be difficult for the patients to perform various movements of daily living, such as standing, walking, and moving. Thus, there is a tendency for the development of gait rehabilitation technologies for rehabilitation treatment of the patients of which movements are inconvenient to be continuously conducted. Currently commercialized gait rehabilitation robots have problems in popularity due to a very high volume, a very high weight, and a very high price because the patients wear robots equipped with a large number of motors or robot arms are mounted on feet. Further, there is a disadvantage in that gait training is impossible only with forces of the patients by directly limiting the lower extremities of the patients with a robot joint. RELATED ART DOCUMENT Korean Patent Application Publication No. 10-2019-0046161. DISCLOSURE Technical Problem The present invention is directed to providing a parallel hybrid driving unit in which a gait force of a patient and a gait force of a robot are separated from each other so that an occupant may rotate a lower extremity mechanism even when a motor is not operated and the lower extremity mechanism may rotate even when the motor is operated and the occupant does not apply a force. The purpose of the present invention is to generate the gait force of the robot for muscle strength assistance according to a gait speed of the occupant. The aspects of the present invention are not limited to the aspects described above and those skilled in the art will clearly understand other aspects not described herein from the following description. Technical Solution One aspect of the present invention provides a driving system for a hybrid gait rehabilitation robot, the driving system including a driving unit that is connected to a footrest of a gait rehabilitation robot and transmits a driving force so that the gait rehabilitation robot operates at a preset speed, a speed detection unit that detects a gait speed of an occupant, and a control unit that controls a speed of the driving unit by comparing the detected speed of the speed detection unit with a speed applied by the driving unit, wherein the driving unit transmits power to the occupant, but a driving force of the occupant is not transmitted to the driving unit. The speed detection unit may detect the gait speed of the occupant by measuring an angular speed of a crank of a lower extremity mechanism connected to the footrest. The driving unit may transmit the power to a pair of footrests using one rotary shaft. The driving unit may include a free wheel body, a decelerator, and a motor, and the free wheel body may transmit a driving force of the motor to the footrest but prevents the driving force of the occupant from being transmitted from the free wheel body to the motor. The driving unit may be driven according to a preset gait speed, and a speed of a motor may be changed according to an angle of a crank. The control unit may control the speed of the motor by Equation 1. Vmotor=f(θc)+Kp(vwalking−a)  [Equation 1] (VMOTOR denotes the speed of the motor, f(θc) denotes a motor speed profile function according to an angle θc of the crank corresponding to a reference gait speed a, vwalking denotes a target gait speed of the occupant, Kp denotes a proportional constant between the gait speed and the speed of the motor, and a denotes a preset occupant reference gait speed). The control unit may determine the speed of the motor in consideration of a speed intention and an acceleration intention of the occupant. The control unit may control the speed of the motor by Equation 2. Vmotor=f(θc)+Kp(vwalking−a)+kv(θc−kg(θc))+ka(θ″c−kg′(θc))  [Equation2] (VMOTOR denotes the speed of the m