This disclosure generally relates to orthoses and, in particular, to orthoses with one or more exotendons.
Individuals with injuries or handicaps often wear orthoses that are not energy efficient. Conventional orthoses worn along legs often provide highly unnatural gaits, such as stiff-legged gaits. A user may become rapidly fatigued due to energy inefficiencies and unnatural gaits. Conventional orthoses are also uncomfortable, especially if worn for an extended period of time, because of the unnatural gait and improper positioning of body parts. If an orthosis does not properly position the wearer's foot, the user's leg muscles may become fatigued.
Some embodiments are directed to an orthosis that can be worn next to a user's leg, prosthesis, or the like. The orthosis or prosthesis can include a framework, rotatable members (e.g., pulleys, guide wheels, etc.), and exotendons extending about the rotatable members. The exotendons can assist the movement of body parts (e.g., leg, foot, etc.) as the user walks, runs, or the like.
In some embodiments, an orthosis includes one or more exotendons. The exotendons can include one or more springs, cables, connectors, or the like. The springs can include stretchable members, helical springs, biasing members, or combinations thereof. In certain embodiments, the exotendon is a multi-piece cable connected together by a tension spring. The tension spring can allow the movement of the exotendon segments to help store energy during exercise (e.g., during the user's gait).
In some embodiments, an orthosis includes a belt assembly, an energy storage apparatus, and an articulatable leg frame. The belt assembly can be secured to a user's body. The energy storage apparatus is coupled to the belt assembly and includes an adjustment device and an exotendon. The adjustment device can be configured to selectively adjust pretension, if any, in the exotendon. The leg frame includes an upper end rotatably coupled to the belt assembly and a lower end coupleable to a lower portion of the user's leg. The exotendon is coupled to the adjustment device and to the lower end of the leg frame such that the exotendon stores energy as a leg moves posteriorly and the exotendon releases stored energy to help the leg move anteriorly.
In certain embodiments, the exotendon comprises one or more cables, springs, tethers, or the like. The exotendon can extend along at least a portion of the user's leg. The exotendon can stretch or elongate to store energy and can contract to assist in body movement of the user.
The adjustment device, in some embodiments, includes a one-way ratchet mechanism. The one-way ratchet mechanism can include a gear with teeth that engage a pawl and can be operated by a user to adjust (e.g., increase or decrease) the tension applied to the exotendon. In some embodiments, the adjustment device is capable of changing the tension in the exotendon by at least about 5%, 10%, 20%, 50%, or the like without significantly changing the motion of the user's legs. In one setting, the pretension in the exotendon can be in a range of about 10 lbs to 30 lbs, and can be increased or decreased at any time. A ratio of a minimum tensile force on the exotendon to a maximum tensile force on the exotendon can be in a range of about 3 to 20 during, for example, normal walking. The maximum tensile force on the exotendon can be in the range of about 15 lbf to about 60 lbf. The minimum tensile force on the exotendon can be less than about 20 lbf, 15 lbf, or 10 lbf during normal walking.
In some embodiments, a system for assisting body movement of a user comprises right and left orthosis apparatuses. The right orthosis apparatus is wearable on the right leg of the user. The right orthosis apparatus stores energy as the right leg moves posteriorly relative to the user's torso and releases stored energy to help move the right leg. The left orthosis apparatus is wearable on the left leg of the user and stores energy independently of the right orthosis apparatus. The left orthosis apparatus is configured to store energy as the left leg moves posteriorly relative to the user's torso and releases stored energy to assist movement of the left leg.
One or both of the right and left orthosis apparatuses can generate a moment proximate to the user's hip to ensure that the orthosis comfortably helps rotate the user's legs. The right orthosis apparatus, in some embodiments, includes a right exotendon that stores energy as the right leg moves rearwardly and releases the stored energy to help move the right leg forwardly. The left orthosis apparatus includes a left exotendon capable of storing energy independent of operation of the right exotendon. The left exotendon stores energy as the left leg moves rearwardly relative to the user's torso and releases stored energy to help move the leg.
In some embodiments, an orthosis includes a belt assembly configured to be secured to the user's body. The belt assembly can include a first arm having a first mounting end, a second arm having a second mounting end, and a back portion. The back portion can be coupled to a first mounting end of a first arm and the second mounting end of the second arm. The back portion can have at least one positioner extending vertically along the user's back when the first arm and the second arm wrap around the user's body (e.g., waist, pelvis, hips, or the like). A leg frame assembly is wearable on the leg of the user and is coupled to the belt assembly.
The positioner can include an anatomical feature locator corresponding in shape to an anatomical feature of the user's body such that the anatomical feature locator engages the anatomical feature of the user's body to align the belt assembly. In some embodiments, the anatomical feature locator is a protrusion or a recess configured to preferentially seat against the user's body.
In some embodiments, the back portion includes a stiffener (e.g., a rigid plate) that extends vertically from the first and second mounting ends along the user's back. For example, the stiffener can protrude upwardly from the arms and overly a portion of the user's back. When a force from the leg assembly is applied to the belt assembly, the belt assembly can maintain its shape to ensure that the leg assembly remains properly aligned with the user's body.
The belt assembly, in some embodiments, includes a belt main body and padding. The belt main body can be made of material that is less compliant than the padding. In some embodiments, the belt main body is made of rigid plastic, metal, or other material capable of withstanding relatively high tensile loads. The padding can be made, in whole or in part, of open-cell foam, closed-cell foam, or the like. The padding can include a cover that surrounds a cushioning material. In some embodiments, the padding is attached to the main body by one or more fasteners (e.g., hook and loop type fastener), snaps, ties, or the like. The padding can be removed from the belt main body for cleaning or maintenance.
Many aspects of the present disclosure can be better understood with reference to the following drawings. Identical reference numbers identify similar elements or acts.
The exotendon 5 can include cables made, in whole or in part, of one or more polymers, plastics, carbon (e.g., carbon fibers), nylon, braided webbing, rope, cables, or some other non-metal or metal material. Metal exotendons can include one or more metal segments that are connected by one more springs (e.g., helical springs, tension springs, or the like) made, in whole or in part, of metal, rubber, polymers, or the like. The springs can have linear behavior consistent with Hooke's law. The exotendon 5 is capable of storing energy produced by movement of the leg and is capable of releasing the stored energy to help the user move the leg. In some embodiments, the tension force applied to the spring 6 increases as the user pushes his/her body forward. The spring 6 stores energy until the user pushes off of the ground. The spring 6 releases energy by contracting so as to help move the user's leg forward.
Each of the pulleys 1, 2, 3, 4 can include a round disk, a semicircular disk, a partial disk, or a lever arm. The pulleys 1, 2, 3, 4 can be rotatably coupled to the frame. The exotendon 5 of
The exotendon 5 wraps around the backside of the ankle pulley 4 and over the front side of the calf pulley 3 before continuing on to the knee pulley 2. The calf pulley 3 can be mounted to a calf bracing or frame member that connects the ankle and knee joints. The calf pulley 3 can be located immediately above the ankle pulley 4 or at any other suitable location.
The exotendon 5 can extend away from the calf pulley 3 and travel across the front side of the knee pulley 2 and connect to the spring 6 between the knee and the hip joints. The exotendon 5 leaves the spring 6 and runs over the top of the hip pulley 1. The hip pulley 1 can be located off axis and above the operator's hip joint center or at any other suitable location.
After wrapping over at least a portion of the hip pulley 1, the exotendon 5 terminates at a termination region 11 coupled to the belt. The exotendon 5 can be rigidly coupled to the belt 8 at a location behind and at the same general height as the top of the hip pulley 1. The termination region 11 can include a spool which allows slack in the exotendon 5 to be removed by turning a knob 12 and spooling the excess cables onto the center shaft 11. A ratchet mechanism can prevent unspooling of the exotendon 5 and allows the operator to apply a preload. The preload can be selected based on the desired operation by the user. In some embodiments, the preload is in a range of about between zero and fifty pounds. Other preloads are also possible, if needed or desired. A button can disengage the ratchet and allow the tension in the exotendon 5 to be released by unspooling of the exotendon 5.
In non-limiting embodiments, hip pulleys can range in size from about one and a half inches to about five inches in diameter, while ankle pulleys range in size from about four inches to about twelve inches in diameter. In some embodiments, the hip pulley has a diameter of about 6 inches. The stiffness of the spring 6 can be in the range of about one pound per inch to thirty pounds per inch, and the displacement of the spring throughout one gait cycle is between one half and four inches. Other dimensions, stiffnesses, and spring displacements are also possible, if needed or desired. The exotendon can include any number of separate springs or integral springs.
The exotendon 5 terminates at the toe termination region 10 and wraps behind the ankle pulley 4, in front of the calf pulley 3, knee pulley 2 and hip pulley 1, and terminates at the hip termination mechanism 9 mounted to the belt 8 behind and in line with the top of the ankle pulley 1. In use, preload tension is added to the exotendon 5 during stance, such that between about zero to about fifty pounds of force is applied to the exotendon 5 during stance. Tension is applied by turning the knob 12 connected to the belt termination region 11 (
The belt diameter and fit can be adjusted in the front and the back so that the hip pulleys 1 remain generally fixed relative to the operator's hip joint centers as the belt 8 is tightened. The belt 8 can be tightened in the front by pulling webbing 16 through the center buckle 17. The belt 8 can be tightened in the back by loosening the screws and t-nuts 19 that bind the back member 13 to the arms 14 and 15, and sliding the arms 14 and 15 relative to the back member 13. Once the arms 14 and 15 are in the desired position relative to the back member 13, the screws and t-nuts 19 are retightened, thereby holding the back member 13 and the arms 14 and 15 together.
The orthosis 100 includes a belt assembly 104, energy storage apparatuses 110a, 110b (collectively “110”), and leg frame assemblies 112a, 112b (collectively “112”). The belt assembly 104 can securely hold the user to position the leg frame assemblies 112a, 112b alongside the user's right and left legs, respectively. The leg frame assemblies 112a, 112b have upper ends 113a, 113b and lower portions 115a, 115b. The upper ends 113a, 113b are rotatably coupled to the belt assembly 104. The lower portions 115a, 115b are coupleable to lower portions of a user's right and left legs, respectively. Each exotendon 130a, 130b stores energy as the leg to which it is coupled moves posteriorly and releases the stored energy to help move the leg forward. Significant amounts of energy can be repeatedly stored and released to assist body movement of the user.
Referring to
The description of one energy storage apparatus 110a, 110b applies equally to the other energy storage apparatus, unless clearly indicated otherwise. The energy storage apparatus 110a of
Referring to
The user's foot can be on a foot platform 174a which can be configured to fit inside of footwear 175a (e.g., a shoe, a boot, or the like). In some embodiments, the foot platform 174a is a foot orthosis upon which the user's foot can be placed and can be made, in whole or in part, of a rigid plastic, metal, a composite material, or other materials capable of retaining its shape during use. The foot platform 174a can include a cushioning layer made of a compliant material (e.g., rubber, foam, or the like). For example, the foot platform 174a can include a lower rigid layer and an upper cushioning layer adhered to an upper surface of the lower rigid layer. When the exotendon 130a is tensioned, the foot platform 174a can maintain its shape to limit or prevent bending of the user's foot. In some embodiments, the platform 174a and the footwear 175a are integrated together. For example, the footwear 175a can be a shoe with a rigid sole configured to prevent unwanted deflection of the user's foot. One or more stops (e.g., hard stops) can be used to prevent or limit foot drop. The stops can be protrusions or other stationary features that physically contact and limit movement of the foot platform 174a. Alternatively, one or more biasing members (e.g., springs) can be used to control foot location.
Referring again to
Referring to
Referring to
An ankle frame joint 186a of
The exotendon 130a can resiliently stretch and store potential energy. When the right leg is positioned rearwardly, the energy stored in the exotendon 130a can be released as the exotendon 130a contracts to help drive the leg forward. In some embodiments, the exotendon 130a helps begin leg swing. As shown in
The exotendon 130a can extend along most of a length of the user's leg and can store most of the energy in a biasing member in the form of a tension spring 227a. The length, position, and orientation of the exotendon 130a can be selected to achieve desired action. As shown in
As shown in
The spring 227a can be positioned adjacent to the upper frame member 156a and can include one or more tension springs (illustrated), helical springs, elongatable members (e.g., rubber elongate members), bands, or the like. The spring 227a can be made of metal, polymers, elastomers, combinations thereof, or the like. The illustrated spring 227a is a tension spring made, in whole or in part, of steel (e.g., spring steel). In some embodiments, a plurality of springs can be coupled together.
Referring to
In some embodiments, the coupler 264a can be coupled to the exterior of the user's footwear 175a (
Referring to
Referring to
A user can periodically adjust the preload force, if any, in the exotendon 130a based upon, for example, the activity to be performed. If a user is fatigued or weak, the tension of the exotendon 130a can be increased to provide an increased amount of assistance with body movement. To reduce assistance, the tension in the exotendon 130a can be decreased.
The adjustment mechanism 289a further includes a cover 400, an arm assembly 410, the spool 300a, and a gear assembly 414. The cover 400 can be coupled to the spool 300a to cover the arm assembly 410. In some embodiments, including the illustrated embodiment of
The arm assembly 410 includes the arms 302, 304 and a central member 430. The central member 430 has central stops 432, 434 for limiting rotation of the arms 302, 304, respectively. The arm 302 can rotate until an arm stop 440 contacts the central stop 432. The arm 304 can rotate until an arm stop 445 contacts the central stop 434.
A spool 300a is rotatably coupled to the bracket 290a by a pivot member 461. The spool 300a has a groove 450 capable of receiving the exotendon 130a. The exotendon 130a can wrap around the spool 300a for convenient storage. The spool 300a can be made, in whole or in part, of metal, plastic, or polymers, and can have an outer diameter in a range of about 4 inches to about 8 inches. Other diameters can also be used based on the desired amount of adjustability.
The gear assembly 414 can be fixedly coupled to the spool 300a by a plurality of fasteners 451a, 451b, 451c, 451d such that the gear assembly 414 and spool 300a rotate together. When a user rotates the spool 300a in the counterclockwise direction (indicated by arrows 452), the pawl 305a moves in and out of the teeth located at the outer periphery of the gear assembly 414. The teeth can be inclined to allow counterclockwise rotation of the gear assembly 414 while the pawl 305a slides into and out of the teeth. The pawl 305a prevents rotation of the gear assembly 414 in the opposite direction. When the exotendon 130a applies a moment (represented by arrow 462) in the clockwise direction, the pawl 305a can prevent rotation of the gear assembly 414.
The lever arm 323a of the release device 320a can be rotated about an axis of rotation 437 (e.g., rotated in a clockwise direction as indicated by an arrow 441) to move the pawl 305a away from the gear assembly 414. After the pawl 305a is spaced apart from the teeth, the gear assembly 414 can freely rotate in the clockwise direction about the axis of rotation 189a to reduce the tension, if any, in the exotendon 130a. Other types of puller units (e.g., electromechanical adjustment mechanisms), one-way ratchet mechanisms, tensioners, and locking mechanisms can also be used.
Referring to
The back portion 124 can have one or more alignment features configured to keep the belt assembly 104 positioned relative to the user's body. Non-limiting exemplary alignment features 503 (illustrated in phantom line) can include, without limitation, one or more ribs, grooves, protrusions, or the like that can interact with the anatomical structures to reduce, limit, or substantially eliminate unwanted movement between the belt assembly 104 and the user body, thereby limiting or minimizing misalignment of the energy storage apparatuses 110a, 110b. In some embodiments, the alignment feature 503 is a vertically extending recess or protrusion positioned in the middle of the back portion 124. The alignment feature 503 can mate with the user's back or spine such that interaction between alignment feature 503 and the user's body can help maintain alignment of the belt assembly 104. In some embodiments, the alignment feature 503 is an elongate protrusion that can fit conveniently between portions of the sacrospinalis on either side of the spinous process. The belt assembly 104 can have other types of anatomical alignment features corresponding in shape to an anatomical feature of the user.
Referring to
The back portion 124 of
From 0 to about 5 seconds, the user is preparing to walk. At 509, the user's body moves past the left leg and the load applied to the exotendon 130b increases. At 510, the user's left leg is behind his/her torso as the left foot pushes off the ground. The load on the exotendon 130b is reduced from the local maxima of about 23.5 lbs at 510 as the user's leg swings forward. The energy stored in the elongated or stretched exotendon 130b is released as the exotendon 130b contracts to help the move the left leg forward. The user's left heel strikes the ground at 520. The force further decreases to a local minima at 522 corresponding to the user transferring his/her body weight on the left foot. The user's body moves over the left leg to increase the force on the exotendon 130a from 522 to 530.
At 540, the user's right leg is positioned generally underneath the user's body. The exotendon 130a is pretensioned with a force of about 15 lbs. As the right leg moves forward, the force applied to the exotendon 130a decreases to a local minima of about 6 lbs at 544 corresponding to when the user's heel strikes the ground. The user transfers weight corresponding to a local minima of 5 lbs at 546. As the user moves his/her body forward and over the right foot, the force applied to the exotendon 130a increases as the right leg moves posteriorly of the user's torso. At 548, the user's right foot pushes off of the ground and the force applied to the exotendon 130a is about 21 lbs. The energy stored in the elongated or stretched exotendon 130a is released as the exotendon 130a contracts to help the move the right leg forward.
From 0 to about 2 seconds, the user is preparing to walk. A 606, the user's right leg is lifted and moves in front of the user. The exotendon 103a contracts and releases stored energy to help move the right leg forward as the force decreases from about 18 lbs at 606 to about 6 lbs-7 lbs at 607. From 607 to 608, user moves his/her body over the right leg and the exotendon 103 is stretched. From 608 to 609, the user's body moves past the right leg and the load applied to the exotendon 130a increases. At 609, the user's right leg is behind his/her torso as the right foot pushes off the ground. The load on the exotendon 130a is reduced from the local maxima of about 26 lbs at 609 as the user's right leg swings forward. The energy stored in the stretched exotendon 130a is released as the exotendon 130a contracts to help swing the right leg forward. The user's right heel strikes the ground at 620. The load on the exotendon 130a further decreases to a local minima of about 6 lbs to about 7 lbs at 622 corresponding to the user transferring his/her body weight to the right foot.
The exotendon 130b is pretensioned with a force of about 17 lbs to about 20 lbs. At 640 of the curve 602, the user's left leg is positioned generally underneath his/her body. As the left leg moves forward, the force applied to the exotendon 130b decreases to a local minima of about 4 lbs at 644 corresponding to when the user's left foot is on the ground. As the user moves his/her body forward and over the left foot, the force applied to the exotendon 130b increases. From 644 to 648, the force applied to the exotendon 130b increases and causes elongation or stretching of the exotendon 130b. At 648, the user's left foot pushes off the ground and the force applied to the exotendon 130b is about 23 lbs to about 24 lbs. The energy stored in the stretched exotendon 130b is released as the exotendon 130b contracts to help propel the left leg forward.
In contrast, at least some of the embodiments of the present technology can provide relatively low forces, as shown in
The hip curves 770, 772 correspond to the maximum moment curve and minimum moment curve, respectively, of at least some embodiments of the orthosis 100 of
At about 30% to about 35% of the gait, both curves 770, 772 gradually increase to local maximums 774, 776, respectively, at about 40% to about 50% of the cycle gait.
Ankle curves 780, 782 correspond to maximum and minimum curves of negative moments capable of being generated by the orthosis 100 of
The controller 826 is coupled to a belt assembly 840 and can generally include, without limitation, one or more central processing units, processing devices, microprocessors, digital signal processors (DSP), application-specific integrated circuits (ASIC), and the like. To store information, controllers also include one or more storage elements, such as volatile memory, non-volatile memory, read-only memory (ROM), random access memory (RAM), and the like. The controller 826 can include a display 850. The display 850 can include, without limitation, a LCD screen, a monitor, an analog display, a digital display (e.g., a light emitting diode display), or other devices suitable for displaying information. The display 850 can display the settings of the energy storage devices, force profiles, moment profiles, data collected by sensors (e.g., pressure applied by user, tension of exotendons, or the like), or any other information.
The controller 826 can store information. The term “information” includes, without limitation, one or more programs, executable code or instructions, operating instructions, combinations thereof, and the like. The controller 826 can store a wide range of different programs, including programs for adjusting the settings or the exotendon before and/or during use. The setting can be maintained until another program is selected by the user. In other embodiments, a program can be selected to provide variable performance based on, for example, signals from sensors (e.g., force sensors). In one exemplary non-limiting closed-loop embodiment, a program can be used to adjust loading of the exotendon 830a based on output from sensors. In open-loop embodiments, loading of the exotendon 830a is set by the user. For example, the user can select the tension in the exotendon 830a when the user stands vertically. The controller 826 can include an input device 860 (e.g., an input display, keyboard, touchpad, controller module, or any peripheral device for user input) and an internal power supply (e.g., one or more batteries or other type of power storage device) for powering the motor 820a, as well as other components of the orthosis 800.
Sensors 851a, 852a, 853a can be in communication with the controller 826. The sensors 851a, 852a, 853a can detect applied movement to analyze characteristics of the gait (e.g., weight transfer, timing of heel strikes, cadence, or the like), gait pattern, or the like and can be accelerometers, gyroscopes, or other types of motion sensors. Additionally or alternatively, one or more of the sensors 851a, 852a, 853a can be force sensors (e.g., torque sensors, moment sensors, etc.) capable of generating an electrical output (e.g., signals) based on mechanical input. In some embodiments, a foot platform 874 includes sensors 875 in the form of pressure sensors. The feedback from the sensors 875 are used to adjust the settings of the orthosis 800.
Unless the context requires otherwise, throughout the specification and claims which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense, that is as “including, but not limited to.”
As used in this specification and the claims, the singular forms “a,” “an,” and “the” include plural referents unless the content clearly dictates otherwise. It should also be noted that the term “or” is generally employed in its sense including “and/or” unless the context clearly dictates otherwise. The orthoses disclosed herein can be used or modified to be used with different body parts, include the legs, arms, fingers, or the like. Additionally, the orthosis can be combined with prosthesis or features described herein can be applied to a prosthesis. The components, configurations, and/or characteristics can be selected to achieve the desired amount of assistance.
The various embodiments described above can be combined to provide further embodiments. All of the U.S. patents, U.S. patent application publications, and U.S. patent applications referred to in this specification and/or listed in the Application Data Sheet, are incorporated herein by reference, in their entirety. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications, and publications to provide yet further embodiments. The orthoses can be modified to provide desired functionality, comfort, or the like. U.S. Pat. No. 7,549,969 discloses various types of orthoses, apparatuses, frameworks, springs, joints, cables, and the like that can be incorporated into the embodiments disclosed herein. U.S. Application No. 12/769,387 filed on Apr. 28, 2010 discloses sockets, materials, and other features that can be incorporated into the embodiments shown in
These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.
This application claims the benefit of U.S. Provisional Application No. 61/452,557 entitled “ORTHOSIS WITH EXOTENDON” filed Mar. 14, 2011, which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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61452557 | Mar 2011 | US |