Man-machine compatible elbow joint rehabilitation robot

Abstract

The invention provides a man-machine compatible elbow joint rehabilitation robot, and relates to the technical field of medical instruments. The human-machine compatible elbow joint rehabilitation robot comprises an elbow joint flexion / extension active movement unit, an elbow joint inward rotation / outward rotation active movement unit, an elbow joint passive movement unit and a hand passive movement unit. Some passive motion pairs are additionally arranged at the man-machine connecting position, and the man-machine compatibility requirement can be met without strict alignment of machine joints and human body joints through motion of the passive free pairs. The series elastic driver is added between the driving motor and the load, the elastic characteristic of the tendon is simulated through the series elastic driver to improve the energy efficiency, in addition, part of energy is stored and then released slowly when the motor is started and stopped and is accidentally impacted, the time of the whole process that force generated by the motor acts on a patient is prolonged, and the energy efficiency is improved. The effect of reducing impact on the body of the patient is achieved, secondary injury to the patient when the machine is started and stopped is effectively avoided, and discomfort of the patient is reduced.

Description

Technical Field

[0001] This invention provides a human-machine compatible elbow joint rehabilitation robot, belonging to the field of medical device technology. Background Technology

[0002] Currently, elbow joint rehabilitation robots are mainly divided into end-effector traction robots and exoskeleton robots. End-effector traction robots only fix the patient's hand or forearm, and move the handle in a plane or space to drive the entire upper limb (including shoulder, elbow, and wrist) to perform compound movements. Their structure is relatively simple, but their precision in isolated training of a single elbow joint is slightly weaker, and the movement path is not precise enough. Exoskeleton rehabilitation robots use a fixation device to fix the patient's upper limb to the robot, and drive the joint to directly match the flexion / extension and internal / external rotation movements of the elbow joint. Their structure is simple and control is direct. This method provides more precise motion control and joint proprioception.

[0003] Meanwhile, current elbow joint rehabilitation robots generally only have two active degrees of freedom to drive the elbow joint's flexion / extension and internal / external rotation movements. This aims to reduce adverse forces and discomfort experienced by patients during rehabilitation training through control, but it doesn't eliminate the unpleasant human-machine interaction forces caused by axial misalignment during elbow joint movement by adding more compatible passive kinematic pairs. Furthermore, most existing elbow joint rehabilitation robots use motor drives, with the motor directly connected to the load via a reducer. The start and stop of the motor generate significant forces that impact the body, potentially causing secondary injury if the force is too great. Traditional elbow joint rehabilitation robots rely on motor control to minimize impact, thus failing to significantly reduce secondary injury to the body. Summary of the Invention

[0004] Based on this, the present invention provides a human-machine compatible elbow joint rehabilitation robot. The present invention adds passive kinematic pairs at the human-machine interface. Through the movement of these passive free pairs, the robot joints do not need to be strictly aligned with the human joints to meet human-machine compatibility requirements, solving the problem of traditional exoskeleton rehabilitation robots requiring strict and accurate fitting to ensure precise axis alignment. Furthermore, the passive movement can reduce or even eliminate adverse interaction forces caused by human joint axis misalignment during rehabilitation training. Regarding the issue of significant forces causing patient discomfort during robot start-up, shutdown, or accidental impacts, the present invention adds a series elastic actuator between the drive motor and the load. This series elastic actuator stores some energy during motor start-up and shutdown and then slowly releases it, prolonging the time the force generated by the motor acts on the patient, thereby reducing the motor start-up and shutdown force on the patient and effectively avoiding secondary injury and reducing patient discomfort during machine start-up and shutdown.

[0005] The present invention is specifically implemented using the following technical solutions: A human-machine compatible elbow joint rehabilitation robot includes an active elbow joint flexion / extension motion unit, an active elbow joint internal / external rotation motion unit, an elbow joint passive motion unit, and a hand passive motion unit. The elbow joint flexion / extension active motion unit consists of a servo motor, a reducer, a motor frame, a bevel gear, a bevel gear, a flat key, a metal plate, a series elastic actuator, a rotating shaft, and a support plate. The passive motion unit of the elbow joint consists of human-machine interface two, four flanges, a cross shaft, bracket one, bracket two and base; The elbow joint internal / external rotation active motion unit consists of two servo motors, two reducers, six locking sliders, two optical shafts, eight aluminum alloy profiles, two motor frames, two flat keys, a pinion, a gear ring, two connecting shafts, rotating parts, and three human-machine interface parts. The passive hand movement unit consists of two support arms, two optical axes, a handle, two vertical moving sliders, and one horizontal moving slider.

[0006] Preferably, the cross shaft of the elbow joint passive motion unit is fixedly connected to the first bracket and the second bracket via four flanges. The flanges have four through holes and are fixed to the first bracket and the second bracket with bolts to form a Hooke pair. The first bracket and the second bracket each have through holes in the middle and are connected to the second human body connector and the base with bolts.

[0007] Preferably, the base is composed of four aluminum alloy profiles placed horizontally and connected by angle brackets. The lower end of the profiles is connected to the fixing component by T-bolts. The fixing component is connected to the ball screw moving block by four bolts. The upper end of the ball screw is equipped with a handwheel and a locking device. The handwheel controls the moving block to move up and down to adjust the overall height of the robot. The locking device fixes the moving block. The base has through holes on both sides.

[0008] Preferably, in the elbow joint flexion / extension active motion unit, the motor and the reducer are connected by bolts, and the reducer and the motor frame are connected by four bolts at the four corners. The motor frame has a through slot at its upper end, and the metal plate has a through hole. The motor frame and the metal plate are connected by bolts, and the metal plate is connected to the base by T-bolts. The reducer shaft has a keyway, which is connected to the bevel gear. The bevel gear and the bevel gear mesh with each other in the horizontal and vertical directions. The bevel gear has threaded holes on both sides and is connected to the series elastic actuator with bolts; the series elastic actuator is connected to the lower end of the rotating shaft, the rotating shaft is placed vertically on the metal plate, and the upper end of the rotating shaft is connected to the support plate.

[0009] Preferably, the six locking sliders in the elbow joint internal / external rotation active motion unit are evenly divided into two groups and connected by two optical axes. Two sliders at one end are bolted to the support plate, and the remaining four locking sliders are fixedly connected to the profiles. The eight profiles are connected to each other by angle brackets. Four profiles are placed horizontally to form a base, and a single profile in the middle is placed horizontally. Two profiles are placed vertically, and one profile is connected to the two vertical profiles to form a gantry shape. The second motor is bolted to the second reducer, and the second reducer is bolted to the second motor frame. The second motor frame has through holes on both sides of its bottom, which are fixed to the profiles with T-bolts. The reducer has a keyway on its two rotating shafts, which are connected to the pinion via a flat key. The pinion meshes with the gear ring in the vertical direction. The upper ends of both sides of the gear ring have threaded holes, which are connected to the rotating component with bolts. The rotating component has sliding grooves at the front and rear. The connecting shaft has threaded holes at both ends, which are connected and fixed to the gantry frame profile and the rotating component with bolts. The human-machine interface component three is bonded and fixed to the rotating component.

[0010] Preferably, the two support arms in the passive hand movement unit have a through hole in the middle, which is fixed to the rotating part with bolts; a through groove is opened at the end of the support arm, and the two vertical moving sliders have through holes on both sides, which are connected to the support arm with bolts; The horizontally movable slider has two through holes in the middle and one through hole at the bottom, through which the optical axis passes; the handle has a threaded hole at the bottom for bolting to the through hole at the bottom of the horizontally movable slider. Compared with the prior art, the present invention has the following beneficial effects: 1. The human-machine compatible elbow joint rehabilitation robot of the present invention has two degrees of freedom: internal / external rotation and flexion / extension of the elbow. It can drive the patient's elbow joint to perform independent rotational movements and combined movements of the two degrees of freedom. It can enable the patient's elbow joint to perform rehabilitation movements within the standard human elbow joint space range of motion, thereby enabling the patient to carry out more comprehensive and effective rehabilitation training.

[0011] 2. The entire design of this invention is based on gear meshing, resulting in smooth transmission and low noise.

[0012] 3. By adding a passive moving component, this invention enables rehabilitation exercises to compensate for wear errors and joint axis misalignment without requiring real-time alignment of the human-machine joints. This eliminates additional torque between the human and machine, avoids secondary injury to the patient, and allows for more effective rehabilitation training.

[0013] 4. By adding a series elastic actuator, this invention reduces the instantaneous force exerted by the robot on the patient during the start-up, shutdown, and accidental impact of the robot in rehabilitation exercises, thereby minimizing secondary damage to the patient, reducing patient discomfort, and making rehabilitation exercises safer and more comfortable.

[0014] 5. Compared with traditional rehabilitation robots, the present invention is smaller in size, lighter in structure, and more portable, better meeting the needs of patients to carry out rehabilitation training in multiple scenarios. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the base structure of the human-machine compatible elbow joint rehabilitation robot of the present invention; Figure 2 This is a schematic diagram of the active motion unit for elbow flexion / extension of the human-machine compatible elbow joint rehabilitation robot of the present invention. Figure 3 This is a schematic diagram of the active motion unit for internal / external rotation of the elbow joint in the human-machine compatible elbow joint rehabilitation robot of the present invention. Figure 4 This is a schematic diagram of the passive motion unit structure of the elbow joint of the human-machine compatible elbow joint rehabilitation robot of the present invention. Figure 5 This is a schematic diagram of the passive motion unit structure of the human-machine compatible elbow joint rehabilitation robot of the present invention; Serial Number Explanation: 101: Ball Screw, 102: Screw Slider, 103: Fixing Component, 104: Locking Device, 105: Handwheel, 106: Profile, 107: Fixing Block, 108: Human-Machine Interface Component 1; 201: Servo Motor 1, 202: Reducer 1, 203: Motor Frame 1, 204: Flat Key 1, 205: Bevel Gear 1, 206: Bevel Gear 2, 207: SEA Axle, 208: SEA Spring, 209: SEA Flange, 210: Metal Plate, 211: Rotating Shaft, 212: Support Plate; 301 302: Locking slider; 303: Slide rail; 304: Servo motor II; 305: Reducer II; 306: Motor frame II; 307: Connecting shaft; 308: Flat key II; 309: Gear ring; 310: Rotating component; 311: Human body connector III; 401: Base; 402: Bracket I; 403: Flange; 404: Cross shaft; 405: Bracket II; 406: Human body connector II; 501: Support arm; 502: Vertical moving slider; 503: Optical axis; 504: Horizontal moving slider; 505: Handle. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the preferred embodiments of this invention will be described in further detail below with reference to the examples. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0017] A human-machine compatible elbow joint rehabilitation robot includes an active elbow joint flexion / extension motion unit, an active elbow joint internal / external rotation motion unit, an active elbow joint motion unit, and a passive hand motion unit. The active elbow joint flexion / extension motion unit comprises a servo motor, a reducer, a motor frame, a bevel gear, a bevel gear, a flat key, a metal plate, a series elastic actuator, a rotating shaft, and a support plate. The passive elbow joint motion unit comprises a human-machine interface connector, four flanges, a cross shaft, a bracket, a bracket, and a base. The active elbow joint internal / external rotation motion unit comprises a servo motor, a reducer, six locking sliders, two optical shafts, eight aluminum alloy profiles, a motor frame, a flat key, a pinion, a gear ring, two connecting shafts, rotating components, and a human-machine interface connector. The passive hand motion unit comprises two support arms, two optical shafts, a handle, two vertically moving sliders, and one horizontally moving slider.

[0018] like Figure 1 As shown, the specific structure of the base of the rehabilitation robot of the present invention is as follows: Four profiles 106 are placed horizontally and connected by angle brackets to form the base. The lower end of the profiles 106 is connected to the fixing member 103 by T-bolts. The fixing member 103 is connected to the lead screw slider 102 by four bolts. The handwheel 105 controls the up and down movement of the lead screw slider 102 to adjust the overall height of the robot. The locking device 104 fixes the position of the lead screw slider 102. Two profiles are connected to the base of the mechanism by angle brackets, and another profile is connected to the two profiles by angle brackets to form a gantry shape. The fixing block 107 has through holes at both ends and is fixedly connected to the profile by T-bolts. The human body connector 108 is glued to the fixing block 107.

[0019] like Figure 2The specific structure of the elbow joint flexion / extension active motion unit of the present invention is as follows: The motor 201 and the reducer 202 are connected by bolts through through holes on the motor housing. The reducer 202 and the motor frame 203 are connected by four bolts through through holes at the four corners. A through slot is formed at the upper end of the motor frame 203, and a through slot is formed on the metal plate 210. The two are connected by bolts, and the horizontal position of the motor can be changed by adjusting the bolt connection position. Through holes are formed around the metal plate 210, which are connected to the profile 106 of the mechanism base with T-bolts. A keyway is formed on the shaft of the reducer 202, which is connected to the bevel gear 205 with a flat key 204. The bevel gear 205 and bevel gear 206 mesh with each other in the horizontal and vertical directions. A threaded hole is formed on the side of the bevel gear 206, which is connected to the SEA wheel axle 207 with bolts. The upper end of the SEA axle 207 has a through hole, which is bolted to the inner ring of the SEA spring 208. The outer ring of the SEA spring 208 also has a through hole, which is bolted to the SEA flange 209. The SEA flange 209 is connected to the rotating shaft 211. The metal plate 210 has a through hole in the middle, and the rotating shaft 211 is placed vertically on the metal plate 210. The upper end of the rotating shaft 211 is connected to the support plate 212. The rotation of the motor 201 shaft drives the bevel gear 205 to rotate, which in turn drives the transmission shaft 211 to rotate through the bevel gear 206, thereby causing the support plate 212 to rotate around the axis to achieve active flexion / extension movement of the elbow joint.

[0020] like Figure 3As shown, the specific structure of the elbow joint internal / external rotation active motion unit of the present invention is as follows: Six locking sliders 301 are connected in groups of three by two slide rails 302. The two right locking sliders 301 are fixed to the support plate 212 with bolts through through holes, and the other four are fixed to the profiles with T-bolts. The bottom section of the locking slider 301 has threaded holes, and bolts are used to lock the sliders and fix their positions. By adjusting the positions of the four locking sliders 301 on the slide rails 302, the extension and retraction of the rehabilitation robot can be achieved to meet the needs of different patients with different arm lengths. Eight profiles are connected to each other by angle brackets. Four profiles are placed horizontally to form a base, a single profile in the middle is placed horizontally, and two profiles are placed vertically. One profile is connected to the two vertical profiles to form a gantry shape. The motor 303 and the reducer 304 are fixedly connected by bolts through through holes in the motor housing. The reducer 304 is connected to the motor frame 305 with bolts. The motor frame 305 has through holes on both sides of its bottom, and is fixedly connected to the profiles with T-bolts. The reducer 304 has a keyway on its rotating shaft, which connects to the pinion 308 via a flat key 307. The pinion 308 meshes with the gear ring 309 in the vertical direction. The gear ring 309 has threaded holes on both sides at its upper end, which are bolted to the rotating component 310. The rotating component 310 has sliding grooves at the front and rear, and the connecting shaft 306 has threaded holes at both ends, which are bolted to and fixed to the gantry frame profile and the rotating component 310. The human-machine interface 311 is glued to the rotating component 310. The rotation of the motor 303 drives the pinion 308 to rotate, which in turn drives the rotating component 310 to rotate, thereby driving the human-machine interface 311 to rotate and achieve internal / external rotation of the human body axis joint.

[0021] like Figure 4 As shown, the specific structure of the passive elbow joint motion unit of the present invention is as follows: The cross shaft 404 is a stepped shaft shape, and the outer end diameter is the same as the diameter of the through hole in the middle of the flange 403. It is fixedly connected to the first bracket 402 and the second bracket 405 through four flanges 403. The flange 403 has four through holes and is fixed to the first bracket 402 and the second bracket 405 with bolts to form a Hooke pair, which can realize two degrees of freedom rotational movement. The first bracket 402 has two through holes in the middle and is fixedly connected to the base 401 with bolts. The second bracket 405 has a through hole in the middle part and is fixedly connected to the human body connector 406 with bolts. When performing elbow flexion / extension movements, the human body connector 406 follows the forearm to rotate in two degrees of freedom through the cross shaft to compensate for the offset of the elbow joint axis in two directions. The base 401 has through holes on both protruding sides and is fixedly connected to the support plate 212 with bolts.

[0022] like Figure 5As shown, the specific structure of the passive hand movement unit of the present invention is as follows: Two support arms 501 have two through holes in the middle, which are fixedly connected to the rotating part 310 with bolts. Through slots are formed at the ends of the support arms 501, and through holes are formed on both sides of the two vertically moving sliders 502. The sliders 502 are connected to the support arms 501 with bolts, enabling the sliders 502 to move vertically. Two through holes are formed in the middle of the sliders 502 for placing and fixing two optical axes 503. Two through holes are formed in the middle of the horizontally moving slider 504, and one through hole is formed at the bottom. The optical axis passes through the middle through hole, enabling the slider 504 to move horizontally. A threaded hole is formed at the bottom of the handle 505, which is fixedly connected to the horizontally moving slider 504 with bolts through the through hole at the bottom of the horizontally moving slider 504. When the hand grips the handle, during elbow internal / external rotation movements, sliders 502 and 504 move vertically and horizontally with the forearm, respectively, compensating for the displacement of the elbow joint axis in both vertical and horizontal directions.

[0023] The embodiments described above are some, but not all, embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A human-machine compatible elbow joint rehabilitation robot, characterized in that, It includes an active motion unit for elbow flexion / extension, an active motion unit for elbow internal / external rotation, a passive motion unit for elbow, and a passive motion unit for the hand; The elbow joint flexion / extension active motion unit consists of a servo motor, a reducer, a motor frame, a bevel gear, a bevel gear, a flat key, a metal plate, a series elastic actuator, a rotating shaft, and a support plate. The passive motion unit of the elbow joint consists of human-machine interface two, four flanges, a cross shaft, bracket one, bracket two and base; The elbow joint internal / external rotation active motion unit consists of two servo motors, two reducers, six locking sliders, two optical shafts, eight aluminum alloy profiles, two motor frames, two flat keys, a pinion, a gear ring, two connecting shafts, rotating parts, and three human-machine interface parts. The passive hand movement unit consists of two support arms, two optical axes, a handle, two vertical moving sliders, and one horizontal moving slider.

2. The human-machine compatible elbow joint rehabilitation robot as described in claim 1, characterized in that, The cross shaft of the elbow joint passive motion unit is fixedly connected to the first bracket and the second bracket via four flanges. The flanges have four through holes and are fixed to the first bracket and the second bracket with bolts to form a Hooke pair. The first bracket and the second bracket each have through holes in the middle and are connected to the second human body connector and the base with bolts.

3. The human-machine compatible elbow joint rehabilitation robot as described in claim 1, characterized in that, The base is composed of four aluminum alloy profiles placed horizontally and connected by angle brackets. The lower end of the profiles is connected to the fixing component by T-bolts. The fixing component is connected to the ball screw moving block by four bolts. The upper end of the ball screw is equipped with a handwheel and a locking device. The handwheel controls the moving block to move up and down to adjust the overall height of the robot. The locking device fixes the moving block. The base has through holes on both sides.

4. The human-machine compatible elbow joint rehabilitation robot as described in claim 1, characterized in that, The motor and the reducer in the elbow joint flexion / extension active motion unit are connected by bolts, and the reducer and the motor frame are connected by four bolts at the four corners. The motor frame has a through slot at its upper end, and the metal plate has a through hole. The motor frame and the metal plate are connected by bolts, and the metal plate is connected to the base by T-bolts. The reducer shaft has a keyway, which is connected to the bevel gear. The bevel gear and the bevel gear mesh with each other in the horizontal and vertical directions. The bevel gear has threaded holes on both sides and is connected to the series elastic actuator with bolts; the series elastic actuator is connected to the lower end of the rotating shaft, the rotating shaft is placed vertically on the metal plate, and the upper end of the rotating shaft is connected to the support plate.

5. The human-machine compatible elbow joint rehabilitation robot as described in claim 1, characterized in that, The six locking sliders in the elbow joint internal / external rotation active motion unit are evenly divided into two groups and connected by two optical shafts. Two sliders at one end are bolted to the support plate, and the remaining four locking sliders are fixedly connected to the profiles. Eight profiles are connected to each other by angle brackets. Four profiles are placed horizontally to form a base, one profile in the middle is placed horizontally, and two profiles are placed vertically. One profile is connected to the two vertical profiles to form a gantry frame. The second motor is bolted to the second reducer, and the second reducer is bolted to the second motor frame. The second motor frame has through holes on both sides of its bottom, which are fixed to the profiles with T-bolts. The reducer has a keyway on its two rotating shafts, which are connected to the pinion via a flat key. The pinion meshes with the gear ring in the vertical direction. The upper ends of both sides of the gear ring have threaded holes, which are connected to the rotating component with bolts. The rotating component has sliding grooves at the front and rear. The connecting shaft has threaded holes at both ends, which are connected and fixed to the gantry frame profile and the rotating component with bolts. The human-machine interface component three is bonded and fixed to the rotating component.

6. The human-machine compatible elbow joint rehabilitation robot as described in claim 1, characterized in that, The passive hand movement unit has a through hole in the middle of the two support arms, which are fixed to the rotating part with bolts; a through groove is opened at the end of the support arm, and through holes are opened on both sides of the two vertical moving sliders, which are connected to the support arm with bolts. The horizontally movable slider has two through holes in the middle and one through hole at the bottom, and the optical axis passes through the middle through hole; the handle has a threaded hole at the bottom, which is bolted to the through hole at the bottom of the horizontally movable slider.

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