Shoulder power-assisted exoskeleton giving consideration to power-assisted stability and redundant degree of freedom

Abstract

The invention discloses a shoulder power-assisted exoskeleton giving consideration to power-assisted stability and redundant degree of freedom, which is provided with a waistband, two shoulder straps and a back skeleton are symmetrically connected to the waistband, the two shoulder straps are connected through a first connecting strap, and the upper end of the back skeleton is connected with the first connecting strap or the shoulder strap close to the first connecting strap through a second connecting strap. The upper end of the back framework is further rotationally connected with a shoulder base through a vertical shaft, the shoulder base is rotationally connected with an arm base through a horizontal shaft, the front end of the arm base is connected with an arm framework, and the front end of the arm framework is connected with an arm connecting piece; a wire passing roller is rotatably supported on the shoulder base, a wire pulling end shaft is arranged on the arm base, the wire pulling end shaft is connected with one end of a first pulling rope, the first pulling rope bypasses the wire passing roller, is vertically downward and is coaxial with a vertical shaft, the other end of the first pulling rope is connected with a force applying element connected to the back framework, a pulling rope limiting block is fixed to the shoulder base, and the pulling rope limiting block is connected with the arm base. And the central line of the first pull rope is prevented from downwards penetrating through the axis of the horizontal shaft.

Description

Technical Field

[0001] The present invention relates to a shoulder-assisted exoskeleton, in particular to a shoulder-assisted exoskeleton that takes both assisted stability and redundant degrees of freedom into consideration. Background Art

[0002] The function of the shoulder-assisted exoskeleton is to provide upward support for the arm when the wearer raises his arm to reduce muscle fatigue in the arm and shoulder. Therefore, its assistance effect and wearing comfort are important factors in determining whether it can be worn for a long time. The assistance effect is usually reflected in the size and stability of the assistance, while the comfort is mainly measured by the overall weight of the device, whether there are pressure points, and whether the degree of freedom meets the movement requirements of the human shoulder and arm.

[0003] The arm structure of a traditional shoulder-assisted exoskeleton is generally composed of a rigid skeleton located on the outside of the human arm and a rigid arm wear structure with a soft pad, that is, the overall exoskeleton arm structure is a rigid structure. Therefore, during the movement of the wearer's arm, the compatibility of the exoskeleton with the human body depends entirely on the freedom system constructed by the rigid shaft of the exoskeleton, and it is very easy for the exoskeleton's freedom to not match the wearer's body. In order to solve this problem, some shoulder-assisted exoskeletons use elastic bands to limit the back skeleton of the exoskeleton and use ball joints between the back skeleton and the waist belt to give it a certain degree of redundant freedom. However, when the force output by the exoskeleton is large, the force generated by the elastic band and the instability of the ball joint movement reduce the force output and further increase the wearing deviation, that is, the existing shoulder-assisted exoskeleton cannot take into account both the power-assisted stability and the redundant freedom. Summary of the invention

[0004] The present invention aims to solve the above-mentioned technical problems existing in the prior art and provide a shoulder-assisted exoskeleton that takes into account both assisted stability and redundant freedom.

[0005] The technical solution of the present invention is: a shoulder-assisted exoskeleton that takes into account both assisted stability and redundant freedom, comprising a waist belt, two shoulder straps and a back frame symmetrically connected to the waist belt, the two shoulder straps being connected via a first connecting belt, the upper end of the back frame being connected to the first connecting belt or a shoulder strap close to the first connecting belt via a second connecting belt, the upper end of the back frame being also rotatably connected to a shoulder base via a vertical axis, the shoulder base being rotatably connected to an arm base via a horizontal axis, the front end of the arm base being connected to the arm frame, and the front end of the arm frame being connected to an arm connecting piece; a wire-passing roller is rotatably supported on the shoulder base, a wire-pull end shaft is provided on the arm base, the wire-pull end shaft is connected to one end of a first pull rope, the first pull rope passes around the wire-passing roller vertically downward and is coaxial with the vertical axis, the other end of the first pull rope is connected to a force-applying element connected to the back frame, a pull rope limit block is fixed to the shoulder base, the pull rope limit block is located below the first pull rope to prevent the center line of the first pull rope from passing downward through the axis of the horizontal axis.

[0006] Preferably, the lower end of the back frame is connected to the waist belt through a first flexible connecting belt, and the arm connecting piece is a second flexible connecting belt, which forms a ring shape through a first length adjustment buckle.

[0007] Preferably, the force-applying element is an elastic element, and an upper transition wheel and a lower transition wheel are respectively provided at the upper and lower ends of the back frame. The lower end of the force-applying element is connected to the second pull rope, and the second pull rope is connected to the upper end of the adjustment belt after passing through the lower transition wheel and the upper transition wheel in sequence. The adjustment belt is connected to the lower end of the back frame through the second length adjustment buckle.

[0008] Preferably, the arm base is connected to the arm frame through a length adjustment mechanism, and the length adjustment mechanism is provided with a long hole and a gear slot arranged in sequence at the front end of the arm base, and the gear slot has multiple sub-gear slots, and the arm frame is provided with a first limiting axis and a second limiting axis, the first limiting axis is movably connected to the long hole, and the second limiting axis is movably connected to the gear slot and can be placed in multiple sub-gear slots, the arm base has a first positioning hole, and the arm frame is provided with second positioning holes equal to the number of sub-gear slots, and the first positioning hole and the second positioning hole are connected by a detachable fastener.

[0009] Preferably, the back frame is provided with a height adjustment mechanism, which includes a sliding base opened on the back frame, a height adjustment rod slidably connected to the sliding base, a plurality of slots are provided on the sliding base and the height adjustment rod, an adjustment spring is fixed on the sliding base, and an adjustment key matching the slot is installed on the adjustment spring.

[0010] Preferably, the lower end of the height adjustment rod is fixedly connected to a wearing structure connector, the wearing structure connector is provided with a webbing groove for the webbing to pass through, and the first flexible connecting belt is a webbing that passes through the webbing groove and is sewn to the belt.

[0011] Preferably, the back frame is composed of two parallel back panels, which are connected to each other by multiple connecting columns. The upper transition wheel and the lower transition wheel are placed between the two parallel back panels, and the adjustment belt and the length adjustment buckle are placed on the outside of the back frame. The second pull rope passes around the transition wheel and passes through the hole in the back panel to connect with the upper end of the adjustment belt. The sliding base is also located between the two parallel back panels, and the adjustment spring is located on the outside of the back frame.

[0012] Preferably, the shoulder base is provided with an arm-flipping prevention limiter adjacent to the horizontal rotation axis.

[0013] The present invention realizes the connection of the arm base, the shoulder base and the back frame through mutually perpendicular vertical axes and horizontal axes, providing a composite degree of freedom for the arm frame; at the same time, the upper end of the back frame is connected to the first connection belt or the shoulder belt near the first connection belt through the second connection belt, and only through a wire roller, the tension generated by the force-applying element can be transmitted to the arm frame when the shoulder base rotates freely around the horizontal axis. When the wearer is in a non-working state (the arm droops naturally), the set pull rope limit block makes the force arm between the pull rope and the horizontal axis extremely small, and there is no need to apply force to resist the tension generated by the elastic element; and when the arm frame is lifted up to make the pull rope leave the pull rope limit block, the pull rope will apply auxiliary lifting tension to the arm frame. The position of the arm frame can be automatically switched between the outside and the top of the wearer's arm, providing space for the movement of the wearer's arm, eliminating the oppression of the rigid arm frame on the human arm, reducing the movement resistance and increasing the redundant degree of freedom, and improving the wearing comfort. At the same time, the present invention has a simple structure, reduces the weight of the exoskeleton, and improves the stability of power output. The back frame can be connected to the waist belt through a flexible connecting belt, which overcomes the instability of relying on the ball joint connection, and can ensure the stability of the overall frame even under high load conditions. The arm connector of the present invention is also a flexible connecting belt, which is formed into a ring shape through a length adjustment buckle, and can adapt to various movements of the human arm and even small movements, further increasing the redundant degrees of freedom. In short, the shoulder-assisted exoskeleton of the present invention as a whole takes into account the stability of force output and the power-assisting effect while retaining the redundant degrees of freedom. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the three-dimensional structure of an embodiment of the present invention.

[0015] Figure 2 , 3 It is a partial structural diagram of an embodiment of the present invention.

[0016] Figure 4 It is a structural schematic diagram of an arm base and an arm frame connected via a length adjustment mechanism in an embodiment of the present invention.

[0017] Figure 5 , 6 It is a schematic structural diagram of the connection between the force-applying element and the back frame according to an embodiment of the present invention.

[0018] Figure 7 , 8 9 is a schematic diagram of the structure of the back frame and height adjustment mechanism in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The present invention provides a shoulder-assisted exoskeleton that takes into account both assisted stability and redundant freedom. Figure 1-9 As shown, a waist belt 1 is provided, and two shoulder straps 2 and a back frame 3 are symmetrically connected to the waist belt 1. The two shoulder straps 2 are connected by a first connecting belt 4. The upper end of the back frame 3 is connected to the first connecting belt 4 or the shoulder strap 2 close to the first connecting belt 4 by a second connecting belt 5. The waist belt 1, shoulder straps 2, first connecting belt 4 and second connecting belt 5 can all be made of flexible and inelastic webbing, which ensures comfortable wearing and reliable connection. The upper end of the back frame 3 is also rotatably connected to the shoulder base 7 through the vertical axis 6, and the shoulder base 7 is rotatably connected to the arm base 9 through the horizontal axis 8. The front end of the arm base 9 is connected to the arm frame 10, and the front end of the arm frame 10 is connected to the arm connecting piece 11; the shoulder base 7 is rotatably supported with a wire-passing roller 12, and the arm base 9 is provided with a wire-pulling end shaft 13, which is connected to one end of the first pull rope 14. The first pull rope 14 passes around the wire-passing roller 12 and extends vertically downward and is coaxial with the vertical axis 6, and the other end thereof is connected to a force-applying element 15 connected to the back frame 3 through a detachable connecting piece. The force-applying element 15 can be an elastic element of different structures such as a spring and an elastic rope, or a power mechanism that pulls the first pull rope 14 such as a motor or a hydraulic cylinder can be used. A drawstring limit block 16 is fixed on the shoulder base 7, and the drawstring limit block 16 is located below the first drawstring 14. When the wearer's arm hangs down, the first drawstring 14 moves forward longitudinally along with the drawstring end shaft 13 on the arm base 9 and the front end hangs down. At this time, the drawstring limit block 16 is set at a position that can ensure that the first drawstring 14 falling thereon is blocked horizontally downward to prevent the center line of the first drawstring 14 from passing downward through the axis of the horizontal axis 8, that is, the center line of the first drawstring 14 will not "cut" the axis of the horizontal axis 8 downward, so that when the arm frame is lifted up again to drive the first drawstring 14 to leave the drawstring limit block 16, the first drawstring 14 will apply a pulling force to the arm frame 10 to assist in lifting.

[0020] The lower end of the back frame 3 is preferably connected to the waist belt 1 through a first flexible connecting belt 17, and the arm connecting piece 11 is a second flexible connecting belt 11-1, which is formed into a ring through a first length adjustment buckle 11-2.

[0021] The arm base 9 is connected to the arm frame 10 through a length adjustment mechanism, and the length adjustment mechanism is provided with a long hole 9-1 and a gear slot 9-2 arranged in sequence at the front end of the arm base 9, and the gear slot 9-2 has a plurality of sub-slots 9-2-1, and the arm frame 10 is provided with a first limiting axis 10-1 and a second limiting axis 10-2, the first limiting axis 10-1 is movably connected to the long hole 9-1, the second limiting axis 10-2 is movably connected to the gear slot 9-2 and can be placed in a plurality of sub-slots 9-2-1, and the arm base 9 has a first positioning hole 9-3, and the arm frame 10 is provided with a second positioning hole 10-3 equal to the number of sub-slots 9-2-1, and the first positioning hole 9-3 and the second positioning hole 10-3 are connected by a detachable fastener 18, and the detachable fastener 18 can be a spring pin or the like.

[0022] When the force-applying element 15 is an elastic element (latex elastic band, metal spring or non-metallic spring), the upper and lower ends of the back skeleton 3 can be respectively provided with an upper transition wheel 3-1 and a lower transition wheel 3-2, and the lower end of the force-applying element 15 is connected to the second pull rope 3-3, and the second pull rope 3-3 is connected to the upper end of the adjustment belt 3-4 after passing through the lower transition wheel 3-2 and the upper transition wheel 3-1 in turn, and the adjustment belt 3-4 is connected to the lower end of the back skeleton 3 through the second length adjustment buckle 3-5.

[0023] The back frame 3 can be composed of two parallel back panels 3-11, and the two back panels 3-11 are connected to each other through a plurality of connecting columns 3-12. The upper transition wheel 3-1 and the lower transition wheel 3-2 are placed between the two parallel back panels 3-11. The adjustment belt 3-4 and the length adjustment buckle 3-5 are placed on the outside of the back frame 3. The second pull rope 3-3 passes through the hole 3-11-1 of the back panel 3-11 and connects with the upper end of the adjustment belt 3-4 after bypassing the transition wheel 3-1.

[0024] The back frame 3 is provided with a height adjustment mechanism, and the height adjustment mechanism is provided with a sliding base 3-6 opened between two back panels 3-11, and a height adjustment rod 3-7 is slidably connected to the sliding base 3-6. A plurality of slots 3-8 are provided on the sliding base 3-6 and the height adjustment rod 3-7, and an adjustment spring 3-9 is fixed on the sliding base 3-6, and an adjustment key 3-10 matching the slot 3-8 is installed on the adjustment spring 3-9.

[0025] The lower end of the height adjustment rod 3-7 is fixedly connected to a wearing structure connector 19, and the wearing structure connector 19 is provided with a webbing groove 19-1 for the webbing to pass through, and the first flexible connecting belt 17 is a webbing that passes through the webbing groove 19-1 and is sewn to be connected to the waist belt 1.

[0026] The shoulder base 7 is provided with an arm-flipping prevention limiter 20 adjacent to the horizontal rotation axis 8 .

[0027] The working process of the shoulder-assisted exoskeleton that takes into account both assisted stability and redundant freedom in the embodiment of the present invention is as follows: the wearer wears a waist belt 1 and puts the arms of both hands into the arm connector 11 respectively, and uses the first length adjustment buckle 11-2 to adjust the tightness of the second flexible connection belt 11-1 so that it is wrapped around the user's upper arm, and the two symmetrical back skeletons 3 fit on the wearer's back. Since the arm base 9 and the arm skeleton 10 can both pitch and swing in the longitudinal direction (swing with the horizontal axis 8 as the axis) and swing left and right in the horizontal direction (the shoulder base 7 connected to the arm base 9 swings with the vertical axis 6 as the axis), the combination of the above two actions can realize the free swing of the arm skeleton 10 relative to the back skeleton 5 in three-dimensional space.

[0028] The force for the auxiliary arm base 9 to lift upward comes from the force element 15. For example, when the force element 15 is an elastic element, the top of the force element 15 is connected to the first pull rope 14, and the bottom is connected to the second pull rope 3-3; the second pull rope 3-3 changes direction through the lower transition wheel 3-2 and the upper transition wheel 3-1, and is connected to the top of the adjustment belt 3-4 located outside the back frame 3, and the bottom of the adjustment belt 3-4 is connected to the bottom of the back frame 3, so that the force of the force element 15 can be adjusted by adjusting the overall length of the adjustment belt 3-4.

[0029] When the wearer does not need to lift heavy objects and his arms hang naturally, the first drawstring 14 fits against the surface of the drawstring limit block 16 below it. Since the drawstring limit block 16 can prevent the center line of the first drawstring 14 from passing downward through the axis of the horizontal axis 8, that is, in this state, the force arm generated by the first drawstring 14 on the mechanical arm assembly is very small (that is, the distance between the first drawstring 14 and the horizontal axis 8 is very small), it can be approximately considered that there is no force arm. Therefore, in this state, the torque generated by the first drawstring 14 on the arm base 9 and the arm skeleton 10 is almost zero, that is, the two will not withstand the upward pull of the first drawstring 14. When lifting heavy objects, the wearer's arm makes a lifting motion, driving the arm base 9 and the arm skeleton 10 to swing upward as a whole. During this process, the position of the pull-wire end shaft 13 in space will change accordingly, until it drives the first pull rope 14 to leave the pull rope limit block 16. Then, the distance between the first pull rope 16 and the horizontal axis 8 (i.e., the lever arm) increases, and the first pull rope 14 transmits the force of the force-applying element 15 to the arm base 9, generating an upward pulling force thereon, thereby assisting the user in making the lifting motion.

[0030] The wearer can also directly adjust the relative position of the height adjustment mechanism on the back frame 3 to improve the wearing comfort. In the initial state, under the action of the adjustment spring 3-9, the adjustment key 3-10 is stuck in a certain slot 3-8, and the height adjustment rod 3-7 is relatively fixed to the sliding base 3-6 in the back frame 3 and cannot slide. When the relative position of the height adjustment rod 3-7 needs to be quickly adjusted, it is only necessary to pull the adjustment spring 3-9 to bend and deform it, and the adjustment key 3-10 on its side will come out of the slot 3-8, and then push the height adjustment rod 3-7 to slide on the sliding base 3-6, and release the adjustment spring 3-9 after sliding to the appropriate position. The adjustment spring 3-9 automatically returns to a straight state, and the adjustment key 3-10 on it enters the slot 3-8 currently matched with it and gets stuck, and the height adjustment rod 3-7 is fixed to the back frame 5 again, thereby realizing the rapid adjustment of the height adjustment rod 3-7.

[0031] When the wearer's lifting action is too large, causing the upper end surface of the arm base 9 to contact the anti-arm flip limiter 20, the arm base 9 cannot continue to swing upward. This is the maximum lifting angle of the device.

[0032] In order to adapt to wearers with different arm lengths and make the wearer more comfortable when wearing this exoskeleton, the total length of the arm base 9 and the arm skeleton 10 can be adjusted as needed; when adjusting, first swing the arm skeleton 10 to let it move relative to the arm base 9, withdraw the second limit axis 10-2 from the current gear slot 9-2, adjust the relative position relationship between the arm base 9 and the arm skeleton 10 to the appropriate total length, and then reinsert the second limit axis 10-2 into the gear slot 9-2 corresponding to the current state. At this time, the axis of the arm base 9 and the axis of the arm skeleton 10 return to a state of being parallel to each other, and then insert the detachable fastener 18 into the positioning hole corresponding to the current gear slot 9-2 (the detachable fastener 18 simultaneously passes through the current first positioning hole 9-3 and the second positioning hole 10-3). The arm base 9 and the arm skeleton 10 are relatively fixed, and the total length of the mechanical arm formed by the two is determined.

Claims

1. A shoulder-assisted exoskeleton that takes into account both assisted stability and redundant freedom, comprising a waist belt (1), two shoulder belts (2) and a back frame (3) being symmetrically connected to the waist belt (1), the two shoulder belts (2) being connected via a first connecting belt (4), characterized in that: The upper end of the back frame (3) is connected to the first connection belt (4) or the shoulder belt (2) near the first connection belt (4) through the second connection belt (5); the upper end of the back frame (3) is also rotatably connected to the shoulder base (7) through the vertical axis (6); the shoulder base (7) is rotatably connected to the arm base (9) through the horizontal axis (8); the front end of the arm base (9) is connected to the arm frame (10); the front end of the arm frame (10) is connected to the arm connecting piece (11); the shoulder base (7) is rotatably supported with a wire roller (12); the arm base ( 9) is provided with a pull-wire end shaft (13), the pull-wire end shaft (13) is connected to one end of a first pull rope (14), the first pull rope (14) passes over the wire roller (12) vertically downward and is coaxial with the vertical axis (6), the other end of the first pull rope (14) is connected to a force-applying element (15) connected to the back frame (3), and a pull rope limit block (16) is fixed on the shoulder base (7), and the pull rope limit block (16) is located below the first pull rope (14) to prevent the center line of the first pull rope (14) from passing downward through the axis of the horizontal axis (8).

2. The shoulder-assisted exoskeleton that takes into account both assistance stability and redundant freedom according to claim 1, characterized in that: The lower end of the back frame (3) is connected to the waist belt (1) via a first flexible connecting belt (17); the arm connecting piece (11) is a second flexible connecting belt (11-1) formed into a ring shape via a first length adjustment buckle (11-2).

3. The shoulder-assisted exoskeleton that takes into account both assisted stability and redundant freedom according to claim 1 or 2, characterized in that: The force-applying element (15) is an elastic element. An upper transition wheel (3-1) and a lower transition wheel (3-2) are respectively provided at the upper and lower ends of the back frame (3). The lower end of the force-applying element (15) is connected to a second pull rope (3-3). The second pull rope (3-3) passes through the lower transition wheel (3-2) and the upper transition wheel (3-1) in sequence and is connected to the upper end of an adjustment belt (3-4). The adjustment belt (3-4) is connected to the lower end of the back frame (3) via a second length adjustment buckle (3-5).

4. The shoulder-assisted exoskeleton that takes into account both assistance stability and redundant freedom according to claim 3, characterized in that: The arm base (9) and the arm frame (10) are connected via a length adjustment mechanism. The length adjustment mechanism is provided with a long hole (9-1) and a gear slot (9-2) arranged in sequence at the front end of the arm base (9). The gear slot (9-2) has a plurality of step slots (9-2-1). The arm frame (10) is provided with a first limiting shaft (10-1) and a second limiting shaft (10-2). The first limiting shaft (10-1) is movably connected to the long hole (9-1). The second limiting shaft (10-2) is movably connected to the gear slot (9-2) and can be placed in the plurality of step slots (9-2-1). The arm base (9) is provided with a first positioning hole (9-3). The arm frame (10) is provided with a second positioning hole (10-3) having the same number as the step slots (9-2-1). The first positioning hole (9-3) and the second positioning hole (10-3) are connected by a detachable fastener (18).

5. The shoulder-assisted exoskeleton that takes into account both assistance stability and redundant freedom according to claim 4, characterized in that: The back frame (3) is provided with a height adjustment mechanism, the height adjustment mechanism is provided with a sliding base (3-6) opened on the back frame (3), a height adjustment rod (3-7) is slidably connected to the sliding base (3-6), a plurality of slots (3-8) are provided on the sliding base (3-6) and the height adjustment rod (3-7), an adjustment spring (3-9) is fixed on the sliding base (3-6), and an adjustment key (3-10) matching the slot (3-8) is installed on the adjustment spring (3-9).

6. The shoulder-assisted exoskeleton that takes into account both assisted stability and redundant freedom according to claim 5, characterized in that: The lower end of the height adjustment rod (3-7) is fixedly connected to a wearing structure connecting piece (19), the wearing structure connecting piece (19) is provided with a webbing groove (19-1) through which a webbing can pass, and the first flexible connecting belt (17) is a webbing that passes through the webbing groove (19-1) and is then sewn and connected to the waist belt (1).

7. The shoulder-assisted exoskeleton that takes into account both assistance stability and redundant freedom according to claim 6, characterized in that: The back frame (3) is composed of two parallel back plates (3-11), the two back plates (3-11) are connected to each other via a plurality of connecting columns (3-12), the upper transition wheel (3-1) and the lower transition wheel (3-2) are arranged between the two parallel back plates (3-11), the adjustment belt (3-4) and the length adjustment buckle (3-5) are arranged on the outside of the back frame (3), the second pull rope (3-3) passes through the hole (3-11-1) of the back plate (3-11) after passing the transition wheel (3-1) and is connected to the upper end of the adjustment belt (3-4), the sliding base (3-6) is also located between the two parallel back plates (3-11), and the adjustment spring sheet (3-9) is located on the outside of the back frame (3).

8. The shoulder-assisted exoskeleton that takes into account both assisted stability and redundant freedom according to claim 7, characterized in that: The shoulder base (7) is provided with an arm-flipping prevention limiter (20) adjacent to the horizontal rotation axis (8).

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