CN111823218B - Variable-rigidity knee joint exoskeleton robot based on shape memory alloy - Google Patents

Abstract

The utility model provides a become rigidity knee joint ectoskeleton robot based on shape memory alloy, belongs to the man-machine and fuses the field, including thigh branch spare, shank branch spare, bearing frame supporting seat, knee joint driving medium, knee joint motor, become rigidity module. The variable stiffness module is fixed on one side of the shank support part, the upper part of the variable stiffness module is connected with the knee joint flange seat through the knee joint transmission part, and the memory alloy in the variable stiffness module can realize stiffness adjustment. The knee joint motor is fixedly connected with the thigh support piece to provide power. The thigh support and the calf support are maintained in a parallel relationship. The upper end of the bearing seat supporting seat is fixedly connected with the bottom of the thigh supporting part, and the turning function of the knee joint is realized by utilizing the internal bearing. The output end piece of the bearing seat is fixedly connected with the shank support piece and used for driving the shank support piece to move. The shape memory alloy is used as a driving principle, so that the overall maneuvering performance of the exoskeleton is improved; the variable-rigidity exoskeleton knee joint can effectively assist a wearer to walk; the material adopts beautiful aluminum alloy, can effectively bear the external force, protects the wearer.

Description

Variable-rigidity knee joint exoskeleton robot based on shape memory alloy

Technical Field

The invention belongs to the field of man-machine fusion, and particularly relates to a variable-rigidity knee joint exoskeleton robot.

Background

With the continuous improvement of the requirements of modern warfare and medical treatment on the enhancement and recovery of the motion capability of a tested group, the knee exoskeleton gradually becomes a research hotspot. The knee joint assisting exoskeleton robot is a mechanical device which can be worn outside the body of an operator, can provide support and assistance for the wearer, and can enhance and restore the motion function of the wearer, so that great practical significance is realized in the development of the knee joint assisting exoskeleton robot.

The traditional variable-rigidity exoskeleton robot can isolate the contact collision between the body and the surrounding environment, protect the safety of a subject, and adapt to different precision, speed and load requirements. However, the variable stiffness units are driven by mechanical structures, and the structures are complex. The exoskeleton system is too large in size and weight to be effectively applied to the exoskeleton device.

Disclosure of Invention

In consideration of the technical background, in order to reduce the weight and enhance the system maneuverability, the variable-stiffness lower limb exoskeleton robot based on the shape memory alloy is developed, the main principle is that the material science characteristics of an intelligent material are combined with the human lower limb movement science, the force and displacement output in the phase change process of the intelligent material are utilized to replace the traditional motor structure to drive a variable-stiffness unit, and the traditional motor is combined to drive the knee joint exoskeleton equipment. On the basis of meeting the requirements of war and medical treatment on exoskeletal equipment, the self weight of the exoskeleton is reduced, and the flexibility of the exoskeleton is enhanced.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the variable-rigidity knee joint exoskeleton robot based on the shape memory alloy is compact and simple in structure, reasonable in gravity center arrangement and stable and reliable in movement. The variable-rigidity knee joint exoskeleton robot comprises athigh support part 1, ashank support part 6, a bearingseat supporting seat 10, a bearing seatoutput end piece 9, a knee joint flange seat 4, a knee joint drivingpart 8, aknee joint motor 3, a motor auxiliary supportingplate 2, a thigh andleg binding plate 11, a shank andleg binding plate 7 and a variable-rigidity module 5.

The bottom of thevariable stiffness module 5 is fixed on one side of theshank support part 6 and is parallel to theshank support part 6, the upper part of the variable stiffness module is connected with the knee joint flange seat 4 through the kneejoint transmission part 8, the moment of the kneejoint motor 3 can be transmitted, bidirectional flexible output is realized by utilizing spring compression, and the stiffness adjustment can be realized by memory alloy in thevariable stiffness module 5; the kneejoint motor 3 is fixedly connected with thethigh support part 1 through the motor auxiliary supportingplate 2 and keeps a vertical relation with thethigh support part 1, and output torque is transmitted to thevariable stiffness module 5 through the knee joint flange seat 4 and the kneejoint transmission part 8 to provide power for the exoskeleton robot; thethigh support 1 and theshank support 6 are kept in parallel relation; the thigh andleg binding plate 11 is arranged in the middle of thethigh support 1, and the shank andleg binding plate 7 is arranged in the middle of theshank support 6 and used for binding and fixing when a human body wears the thigh and leg binding plate; the bearingseat support seat 10 is matched and connected with the bearing seatoutput end sheet 9 through a shaft, the upper end of the bearing seat support seat is fixedly connected with the bottom of the thigh supportpart 1, and the rotation function of the knee joint can be realized by utilizing an internal bearing; the lower end of the bearing seatoutput end piece 9 is fixedly connected with the upper end of theshank support piece 6 and used for driving theshank support piece 6 to move.

Further, thestiffness variable module 5 includes aguide assembly 501, a tensionspring protection guide 502, aguide plate 503, aguide sleeve 504, anoilless bushing 505, aprotection housing 506, aconnection buckle 507, abottom plate 508, amounting plate 510, alinear displacement sensor 509, linear displacementsensor fixing parts 511 and 512, a linear displacementsensor connecting part 513, a memory alloy wiretop fixing part 514, aguide connection shaft 515, aspring 516, amemory alloy wire 518, a memory alloywire binding part 517, and a memory alloy wirebottom fixing part 519. The bottom of theguide assembly 501 is fixedly connected with the extensionspring protection guide 502, and the top of the guide assembly is connected with the kneejoint transmission part 8, so that the moment output by the kneejoint motor 3 can be transmitted to therigidity changing module 5. The extensionspring protection guide 502 is connected to aguide plate 503 through aguide connection shaft 515, and can move up and down along a middle groove of theguide plate 503, and the bottom of theguide plate 503 is connected to aguide sleeve 504. The guidingsleeve 504 is matched with aprotective casing 506 through anoilless bushing 505 for guiding the spring, a connectingbuckle 507 is connected with theprotective casing 506 and abottom plate 508, and theprotective casing 506 is used for protecting the internal structure of the spring. One side of themounting plate 510 is fixedly connected with thelower leg support 6 and is parallel to thelower leg support 6, and the upper part of the mounting plate is connected with thebottom plate 508 to play a role in supporting thevariable stiffness module 5; the lower end of thelinear displacement sensor 509 is arranged outside theprotective shell 506 through linear displacementsensor fixing pieces 511 and 512, and the upper end of thelinear displacement sensor 509 is arranged on the upper side of theguide sleeve 504 through a linear displacementsensor connecting piece 513; thevariable stiffness module 5 only has a one-way compression function, and realizes the two-way flexible design of the variable stiffness driving element through a bilateral symmetrical structure. When the wearer has special conditions such as sudden leg stop, the system absorbs the movement moment of themotor 3 by the single-side variable stiffness unit. Thespring 516 is arranged inside theguide sleeve 504 and theprotective shell 506, and the rigidity of thevariable rigidity module 5 can be adjusted through the tension and compression changes of the spring; the memory alloy wiretop fixing piece 514 and the memory alloy wirebottom fixing piece 519 keep a parallel relation and are used for pre-tightening thememory alloy wire 518; thememory alloy wire 518 forms a plurality of parallel structures by utilizing the memory alloy wirebinding piece 517, the contraction force and the contraction displacement of the memory alloy wire can be increased simultaneously, when the temperature rises, the memory alloy can be effectively contracted, and the shape memory alloy is bound in a crossed mode, so that the output force and the displacement of the variable-stiffness active unit can be effectively improved. The input bearing force unit is provided with a thermocouple at the side, so as to detect the temperature of the shape memory alloy, realize the real-time control of the phase change of the shape memory alloy, and adjust the contraction force and the displacement. Thevariable stiffness module 5 is arranged on two sides of the exoskeleton and is matched with a traditional motor to realize the variable stiffness function of the exoskeleton.

Compared with the prior art, the invention has the beneficial effects that:

(1) the exoskeleton is driven by the shape memory alloy, is light in weight and small in size, and improves the overall maneuvering performance of the exoskeleton.

(2) The variable-rigidity exoskeleton knee joint is designed, a wearer can be effectively assisted to walk, the variable-rigidity exoskeleton knee joint has a variable-rigidity function, and a better driving effect is achieved under the requirement of high maneuverability.

(3) The material adopts beautiful aluminum alloy, and its quality is light, and intensity is high, can effectively bear the external force, protects the person of wearing.

Drawings

Fig. 1 is an overall structural view of a variable stiffness knee exoskeleton robot used in an example of the present invention.

Fig. 2 is a block diagram of a variable stiffness active unit of a variable stiffness knee exoskeleton robot used in an embodiment of the present invention.

Fig. 3 is a structural diagram of the arrangement form of memory alloy wires in the variable stiffness active unit of the variable stiffness knee exoskeleton robot used in the embodiment of the invention.

In the figure: the knee joint rehabilitation device comprises athigh support 1, a motor auxiliary supportingplate 2, aknee joint motor 3, a knee joint flange seat 4, avariable stiffness module 5, ashank support 6, ashank binding plate 7, a kneejoint transmission piece 8, a bearing seatoutput end piece 9, a bearingseat supporting seat 10 and athigh binding plate 11;

501 guide assembly parts, 502 extension spring protection guide parts, 503 guide plates, 504 guide sleeves, 505 oilless bushings, 506 protection shells, 507 connecting buckles, 508 bottom plates, 509 linear displacement sensors, 510 mounting plates, 511 and 512 linear displacement sensor fixing parts, 513 linear displacement sensor connecting parts, 514 memory alloy wire top fixing parts, 515 guide connecting shafts, 516 springs, 517 memory alloy wire binding parts, 518 memory alloy wires and 519 memory alloy wire bottom fixing parts.

Detailed Description

The invention is further illustrated with reference to the following figures and examples.

As shown in fig. 1, the variable-rigidity knee joint exoskeleton robot comprises athigh support part 1, ashank support part 6, a bearingseat supporting seat 10, a bearing seatoutput end piece 9, a knee joint flange seat 4, a knee joint drivingpart 8, aknee joint motor 3, a motor auxiliary supportingplate 2, a thigh andleg binding plate 11, a shank andleg binding plate 7 and a variable-rigidity module 5. The bottom of thevariable stiffness module 5 is fixed on one side of theshank support part 6 and is parallel to theshank support part 6, and the upper part of the variable stiffness module is connected with the knee joint flange seat 4 through the kneejoint transmission part 8; the kneejoint motor 3 is fixedly connected with thethigh supporting part 1 through the motor auxiliary supportingplate 2, and the output torque is transmitted to therigidity changing module 5 through the knee joint flange seat 4 and the kneejoint transmission part 8; thethigh support 1 and theshank support 6 are kept in parallel relation; a thigh andleg binding plate 11 is arranged in the middle of thethigh support 1, and a shank andleg binding plate 7 is arranged in the middle of theshank support 6; the bearingseat support seat 10 is matched and connected with the bearing seatoutput end sheet 9 through a shaft, and the upper end of the bearing seat support seat is fixedly connected with the bottom of thethigh support 1; the lower end of theoutput end piece 9 of the bearing seat is fixedly connected with the upper end of theshank support piece 6.

As shown in fig. 2 and 3, the stiffness-variable knee exoskeleton robot further comprises aguide assembly 501, a tensionspring protection guide 502, aguide plate 503, aguide sleeve 504, anoilless bushing 505, aprotection housing 506, a connectingbuckle 507, abottom plate 508, amounting plate 510, alinear displacement sensor 509, linear displacementsensor fixing parts 511 and 512, a linear displacementsensor connecting part 513, a memory alloy wiretop fixing part 514, aguide connecting shaft 515, aspring 516, amemory alloy wire 518, a memory alloywire binding part 517 and a memory alloy wirebottom fixing part 519. The bottom of theguide assembly 501 is fixedly connected with the extensionspring protection guide 502, and the top of the guide assembly is connected with the kneejoint transmission piece 8; the extensionspring protection guide 502 is connected with aguide plate 503 through aguide connection shaft 515, and the bottom of theguide plate 503 is connected with aguide sleeve 504; theguide sleeve 504 is fitted to theprotective casing 506 through anoilless bushing 505, and aconnection catch 507 connects theprotective casing 506 to abottom plate 508. One side of themounting plate 510 is fixedly connected with thelower leg support 6 and keeps a vertical relation with thelower leg support 6, and the upper part is connected with thebottom plate 508; the lower end of alinear displacement sensor 509 is arranged outside theprotective shell 506 through linear displacementsensor fixing pieces 511 and 512, and the upper end of thelinear displacement sensor 509 is arranged on the upper side of theguide sleeve 504 through a linear displacementsensor connecting piece 513; aspring 516 is mounted inside theguide sleeve 504 and theprotective housing 506; memory alloywire top mount 514 and memory alloywire bottom mount 519 remain in a parallel relationship; thememory alloy wire 518 utilizes memoryalloy wire ties 517 to form multiple parallel structures.

While the invention has been described with reference to the drawings and examples, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

The above-mentioned embodiments only express the embodiments of the present invention, but not should be understood as the limitation of the scope of the invention patent, it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the concept of the present invention, and these all fall into the protection scope of the present invention.

Claims (1)

1. The variable-rigidity knee joint exoskeleton robot is characterized by comprising thigh supporting pieces (1), a shank supporting piece (6), a bearing seat supporting seat (10), a bearing seat output end piece (9), a knee joint flange seat (4), a knee joint driving piece (8), a knee joint motor (3), a motor auxiliary supporting plate (2), a thigh leg binding plate (11), a shank leg binding plate (7) and a variable-rigidity module (5);

the bottom of the variable stiffness module (5) is fixed on one side of the shank support piece (6) and is parallel to the shank support piece (6), the upper part of the variable stiffness module is connected with the knee joint flange seat (4) through a knee joint transmission piece (8) and is used for transmitting the moment of the knee joint motor (3), the two-way flexible output is realized by utilizing the compression of a spring, and the stiffness adjustment can be realized by using the shape memory alloy in the variable stiffness module (5); the knee joint motor (3) is fixedly connected with the thigh supporting piece (1) through the motor auxiliary supporting plate (2) and keeps a vertical relation with the thigh supporting piece (1), and output torque is transmitted to the variable stiffness module (5) through the knee joint flange seat (4) and the knee joint transmission piece (8) to provide power for the exoskeleton robot; the thigh support (1) and the shank support (6) are kept in parallel; the thigh and leg binding plate (11) is arranged in the middle of the thigh support (1), and the shank and leg binding plate (7) is arranged in the middle of the shank support (6) and used for binding and fixing when a human body wears; the bearing seat supporting seat (10) is connected with the bearing seat output end sheet (9) in a matched mode through a shaft, the upper end of the bearing seat supporting seat is fixedly connected with the bottom of the thigh supporting piece (1), and the rotation function of the knee joint is realized by utilizing an internal bearing; the lower end of the output end piece (9) of the bearing seat is fixedly connected with the upper end of the shank support (6) and is used for driving the shank support (6) to move;

the rigidity-variable module (5) comprises a guide assembly part (501), a tension spring protection guide part (502), a guide plate (503), a guide sleeve (504), an oilless bushing (505), a protection shell (506), a connecting buckle (507), a bottom plate (508), a mounting plate (510), a linear displacement sensor (509), a linear displacement sensor connecting part (513), a memory alloy wire top fixing part (514), a guide connecting shaft (515), a spring (516), a memory alloy wire (518), a memory alloy wire binding part (517) and a memory alloy wire bottom fixing part (519); the variable stiffness module (5) only has a one-way compression function, and the two-way flexible design of the variable stiffness active unit is realized through a symmetrical structure on two sides;

the bottom of the guide assembly part (501) is fixedly connected with the extension spring protection guide part (502), and the top of the guide assembly part is connected with the knee joint transmission part (8) to transmit the torque output by the knee joint motor (3) to the variable stiffness module (5); the extension spring protection guide piece (502) is connected with a guide plate (503) through a guide connecting shaft (515) and can move up and down along a middle groove of the guide plate (503), and the bottom of the guide plate (503) is connected with a guide sleeve (504); the guide sleeve (504) is matched with the protective shell (506) through an oilless bushing (505) and used for guiding the spring, and the connecting buckle (507) is connected with the protective shell (506) and the bottom plate (508); one side of the mounting plate (510) is fixedly connected with the lower leg support (6) and is parallel to the lower leg support (6), and the upper part of the mounting plate (510) is connected with a bottom plate (508) for supporting the variable stiffness module (5); the lower end of the linear displacement sensor (509) is arranged on the outer side of the protective shell (506) through a linear displacement sensor fixing piece, and the upper end of the linear displacement sensor (509) is arranged on the upper side of the guide sleeve (504) through a linear displacement sensor connecting piece (513); the spring (516) is arranged inside the guide sleeve (504) and the protective shell (506), and the stretching and compression changes of the spring can adjust the rigidity of the rigidity changing module (5); the memory alloy wire top fixing piece (514) and the memory alloy wire bottom fixing piece (519) keep a parallel relation and are used for pre-tightening the memory alloy wire (518); the memory alloy wire (518) forms a plurality of parallel structures by using the memory alloy wire binding piece (517), the contraction force and the contraction displacement of the memory alloy wire can be increased simultaneously, when the temperature rises, the shape memory alloy contracts effectively, and the memory alloy wire binding piece (517) binds the shape memory alloy in a cross way, so that the output force and the displacement of the variable-stiffness active unit are improved; the exoskeleton robot is provided with a thermocouple for detecting the temperature of the shape memory alloy, realizing real-time control on the phase change of the shape memory alloy, and further adjusting the contraction force and the displacement.

Images