HYBRID SPRING AND MASS COUNTERBALANCING ORTHOTIC
20210236373 · 2021-08-05
Inventors
- Mark Oreschnick (Inver Grove Heights, MN, US)
- Eli Krumholz (Minneapolis, MN, US)
- Julie Lundstrom (Ellsworth, WI, US)
- Shawna Persaud (Lakeville, MN, US)
- Angie Conley (Minneapolis, MN, US)
Cpc classification
F16H25/20
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16H19/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16H2025/204
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
A61H2201/1261
HUMAN NECESSITIES
A61H2201/1669
HUMAN NECESSITIES
B25J9/0006
PERFORMING OPERATIONS; TRANSPORTING
F16H19/0618
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16H2025/2096
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16H2025/2075
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16H2025/2081
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
Abstract
An upper torso augmentation device in which a moment of an arm assembly is tunable by the movement of one or more movable masses. The upper torso augmentation device including an upper arm assembly pivotably coupled to a shoulder assembly, the upper arm assembly including an assisted force mechanism configured to aid in counteracting an effect of gravity upon the upper arm assembly and any payload carried thereby, the assisted force mechanism comprises one or more movable masses configured to move relative to a distal end of the upper arm assembly, thereby affecting a change in a moment of the upper arm assembly.
Claims
1. An upper torso augmentation device in which a moment of an arm assembly is tunable by the movement of one or more movable masses, the upper torso augmentation device comprising: an upper arm assembly pivotably coupled to a shoulder assembly, the upper arm assembly including an assisted force mechanism configured to aid in counteracting an effect of gravity upon the upper arm assembly and any payload carried thereby, wherein the assisted force mechanism comprises one or more movable masses configured to move relative to a distal end of the upper arm assembly, thereby affecting a change in a moment of the upper arm assembly.
2. The upper torso augmentation device of claim 1, wherein the assisted force mechanism comprises at least one spring.
3. The upper torso augmentation device of claim 1, wherein a tension in the at least one spring is adjustable via a pre-tensioning mechanism.
4. The upper torso augmentation device of claim 1, further comprising a lower arm assembly pivotably coupled to the upper arm assembly, the lower arm assembly including a second assisted force mechanism configured to aid in counteracting an effect of gravity upon the lower arm assembly and any payload carried thereby, wherein the second assisted force mechanism comprises one or more lower arm movable masses configured to move relative to a distal end of the lower arm assembly, thereby affecting a change in moment of the lower arm assembly.
5. The upper torso augmentation device of claim 1, wherein the one or more movable masses are moved via at least one of a manual or automated actuation system.
6. The upper torso augmentation device of claim 1, wherein the assisted force mechanism is controllable via a user interface.
7. The upper torso augmentation device of claim 1, wherein the assisted force mechanism further comprises one or more sensor configured to identify known payloads for automatic movement of the one or more movable masses.
8. The upper torso augmentation device of claim 1, wherein the assisted force mechanism includes one or more load cells configured to monitor forces experienced in an arm of a user, wherein a deviation from an expected force value triggers automatic movement of the one or more movable masses.
9. The upper torso augmentation device of claim 1, wherein the assisted force mechanism is configured to provide active resistance as a form of resistance training.
10. The upper torso augmentation device of claim 1, wherein the assisted force mechanism is configured to calculate an amount of work performed by a user over a defined period of time.
11. An upper torso augmentation device, comprising: at least one arm assembly including an assisted force mechanism configured to counteract an effect of gravity upon an arm of a user through a desired range of motion, the assisted force mechanism comprising one or more movable masses configured to move relative to a distal end of the at least one arm assembly, thereby affecting a change in moment of the at least one arm assembly.
12. The upper torso augmentation device of claim 11, wherein the assisted force mechanism includes an actuation system comprising a rotatable lead screw to shift the one or more movable masses along a track.
13. The upper torso augmentation device of claim 11, wherein the assisted force mechanism includes an actuation system comprising a pulley wheel system configured to drive a cable upon which the one or more movable masses is attached in order to affect movement in the one or more movable masses along a length of the at least one arm assembly.
14. The upper torso augmentation device of claim 11, wherein the assisted force mechanism includes an actuation system comprising a rack and pinion system configured to affect movement in the one or more movable masses along a length of the at least one arm assembly.
15. The upper torso augmentation device of claim 11, wherein the assisted force mechanism includes an actuation system comprising a resilient push pull linkage configured to affect movement in the one or more movable masses along the length of the at least one arm assembly.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The disclosure can be more completely understood in consideration of the following detailed description of various embodiments of the disclosure, in connection with the accompanying drawings, in which:
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[0033] While embodiments of the disclosure are amenable to various modifications and alternative forms, specifics thereof shown by way of example in the drawings will be described in detail. It should be understood, however, that the intention is not to limit the disclosure to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter as defined by the claims.
DETAILED DESCRIPTION
[0034] Referring to
[0035] As further depicted in
[0036] Referring to
[0037] Similarly, the optional lower arm assembly 106 can include a tension cable 134 anchored to an indexing disk 136 at a first end 138 and to a distal end 140 of the lower arm assembly 106 at a second end 142 via a spring 144. In some embodiments, the tension cable 134 can travel around one or more bearings 146A/B or pulleys between the first end 138 and the second end 142. For example, in one embodiment, a pair of bearings 146A/B can be utilized to enable rotation of the lower arm assembly 106 beyond an angle at which the tension cable 134 would no longer be constrained by a single bearing 146A.
[0038] In some embodiments, a connecting rod 148 operably coupling the upper arm indexing disk 122 to the lower arm indexing disk 136 can be configured to rotate the lower arm indexing disk 136 based on the position of the upper arm indexing disk 122, thereby increasing or decreasing a tension in the lower arm tension cable 134 based on a shoulder rotation position (e.g., a lateral position with respect to a gravitational reference) of the upper arm assembly 102. For example, in some embodiments, the first indexing disk 122 can be configured to maintain its position with respect to a gravitational frame of reference, regardless of the shoulder rotation of the user and subsequent position of the upper arm assembly. Operably coupling the first indexing disk 122 to the second indexing disk 136 via the connecting rod 148, thus forces the second indexing disk 136 to also maintain its position with respect to a gravitational frame of reference. Accordingly, in some embodiments, the connecting rod 148 is configured to ensure that a counterbalance force of the lower arm assembly 106 (e.g., a tension preload in the lower arm spring 144) is adjusted based on a shoulder angle of the user.
[0039] When the first and second springs 130, 140 are properly preloaded (e.g., via rotation of the upper and lower indexing discs 122, 136) an “ideal” counterbalancing force can be achieved (e.g., a gravitational force exerted upon a user's arm can be completely counterbalanced, thereby creating the effects of weightlessness of the arm to the user), with alignment and friction between components of the upper torso augmentation device 100 being the primary elements negatively affecting an ideal counterbalance throughout an entire desired range of motion. In such embodiments, the spring counterbalance for the patient can be determined by computing a mechanical moment produced by a combination of the patient's arm and the upper torso augmentation device 100. The mechanical moment (also referred to herein as the “torque”) is defined as the total mass (of both the patient's arm and the device 100) multiplied by the distance from the pivot point 123, 137 (e.g., the center of the indexing discs 122, 136) to the center of gravity (CoG) of the total mass.
[0040] In some embodiments, the moment of the lower arm assembly 106 can be defined by the following formula:
Mo.sub.lower arm=Sin Θ.sub.E×((M.sub.lower arm×CoG.sub.lower arm)+(M.sub.user arm×CoG.sub.user arm)
[0041] Where, Mo.sub.lower arm represents the moment of the lower arm assembly, Θ.sub.E represents the flexion angle of the lower arm assembly 106, M.sub.lower arm represents the mass of the lower arm assembly 106, CoG.sub.lower arm represents the center of gravity of the mass of the lower arm assembly 106, M.sub.user arm represents the mass of the user's lower arm, and CoG.sub.user arm represents the center of gravity of the mass of the user's lower arm. The mass of the user's lower arm (and CoG) can include the patient's hand, as well as any payload in the hand.
[0042] In some embodiments, the moment of the upper arm assembly 102 can be defined by the following formula:
Mo.sub.upper arm=MO.sub.lower arm+(Sin Θ.sub.s×((M.sub.upper arm×COG upper arm)+(M.sub.upper arm×CoG.sub.upper arm))
[0043] Where, Mo.sub.upper arm represents the moment of the upper arm assembly, η.sub.s represents the flexion angle of the upper arm assembly 102, M.sub.upper arm represents the mass of the upper arm assembly 102, CoG.sub.upper arm represents the center of gravity of the mass of the upper arm assembly 102, M user arm represents the mass of the user's upper arm, and CoG user arm represents the center of gravity of the mass of the user's upper arm. Note that the above formulas may not account for abduction and adduction angles. Further, the formulas can be defined using sin( ) or cos( ) functions depending on the coordinate system used.
[0044] Adjusting the assisted force mechanism 110, 112 to effectively counteract the respective upper and lower moments (Mo.sub.upper arm, Mo.sub.lower arm) can be done in a variety of ways. For example, in some embodiments, springs 130, 144 can be selected to create an opposing force, equal and opposite to that of the upper and lower moments. Specifically, Hooke's law can be applied to determine an approximate spring constant K required of springs 130, 144. Accordingly, in some embodiments, the springs 130, 144 can be appropriately sized to match the respective weights of the user's upper and lower arms (including any expected payloads).
[0045] Alternatively or in addition to the selection of springs 130, 144 having a specific constant K, a spring preload can be applied to the springs 130, 144, for example by rotating the upper and lower indexing discs 122, 136 relative to a gravitational field, thereby adjusting a tension of the springs 130, 144 as well as displacement of the first ends 124, 138 of the tension cables 120, 134 relative to pivot points 123, 137. In practice it is been found that changing the spring 130, 144 preload can lead to a non-ideal counterbalance, requiring additional input by the patient. To further tune the upper torso augmentation device 100, one or more movable masses can be added to at least one of the upper and/or lower arm assemblies 102, 106.
[0046] Referring to
[0047] Accordingly, since respective upper and lower moments can be tuned to spring having a specific constant K and/or pretension, an “ideal” counterbalance can be achieved if a sufficiently sized mass 150, 152 can be moved over a sufficient distance L.sub.1, L.sub.2 (where L.sub.1, L.sub.2 represented distance between the center of gravity of the mass 150, 152 and the pivot points 123, 137. In some embodiments, a spring preload adjustment can be used in combination with one or more movable masses 150, 152 as an aid in achieving an ideal counterbalance. Further, the positions of the masses 150, 152 can also be used to offset the change in moment introduced by a payload in a user's hand, thereby enabling a single spring to counterbalance the user's arm regardless of the payload held in the user hand.
[0048] Referring to
[0049] In some embodiments, a one-time calibration can be performed to configure the mass 150, 152 (e.g., move the masses 150, 152 a desired distance L.sub.1, L.sub.2 from pivots 123, 137 to achieve desired upper and lower moments) for a user's unique arm. The one-time calibration can include tuning adjusting the distances of the masses 150, 152 in order to create a desired balance in the upper torso augmentation device 100 based on the weight of the user's arm and/or the physical demand/strength profile desired for the patient therapy or treatment. Accordingly, in some embodiments, the movable masses 150, 152 can be utilized to tune the upper torso augmentation device 100 for a specific user.
[0050] In other embodiments, the calibration can be performed on a more frequent basis, for example to account for different payloads grasped by the user. For example, in some embodiments, distances L.sub.1, L.sub.2 from can be dynamically controlled by direct user input via a user interface 166 (e.g., via push buttons, sliders, touchscreen, etc.), which can enable a user to adjust the mass 150, 152 positions based on the payload that the user would like to pick up and/or carry. In such an embodiment, the movable masses 150, 152 can be positioned near distal ends 172, 174 of the upper and lower arm assemblies 102, 106. Upon picking up a payload or object, the movable masses 150, 152 can be moved proximately away from the distal ends 172, 174 to ensure that the respective upper and lower moments (Mo.sub.upper arm, Mo.sub.lower arm) remains substantially unchanged (e.g., the movable masses 150, 152 can shift proximately to reduce the upper and lower moments by approximately the same amount that the picking up the payload increases the upper and lower moments).
[0051] In some embodiments, one or more sensors 168 (e.g., wireless sensors) can be utilized to identify known payloads (specifically a known mass of a payload), thereby enabling an electronic actuation system 154, 156 to automatically adjust the position of the movable masses 150, 152 once the payload has been grasped by the user. Accordingly, the system is configured to provide active assistance, by adjusting a position of one or more movable masses 150, 152 dynamically based on the position of the arm and sensed user input to amplify user input, thereby requiring less user strength to overcome friction and misalignment of the device 100 in counteracting the effects of gravity.
[0052] In yet another embodiment, adjustment of the mass 150, 152 positions can be based on a sensed patient input force. For example, in one embodiment, one or more load cells 170 (e.g., positioned in at least one of the patient arm cuffs 114, 116, 118) can be configured to monitor forces experienced by the arm of the user over a range of positions. Deviations from an expected force value can be used as an aid in moving the masses 150, 152 to a new location in an effort to achieve a more desirable upper and lower moment.
[0053] In some embodiments, the upper torso augmentation device 100 can modify the upper and lower moments to provide active resistance, thereby providing a form of resistance training for a patient by actively opposing the patient input. Users or clinicians can adjust the resistance (or dosage) based on clinical advice. Since the deviation from an ideal counterbalance can be known accurately (known mass, and known distance from pivot or joint), and the amount of movement of the patient's joints can be measured over a course of time, it possible to calculate the amount of work (e.g., force multiplied by displacement) that a patient performs over that period of time. The amount of patient work can be tracked over time, quantifying if the patient strength and endurance is improving or worsening over time, and allowing for controlled experiments to assess the effects of using the device and the dosage of the resistance introduced.
[0054] The actuation system 154, 156 can be configured to enable movement of the one or more masses relative to the pivots 123, 137 can have a variety of configurations. For example, in some embodiments, the actuation system 154, 156 can be a sliding mass system (e.g., including masses 150, 152) configured to move along the respective upper and lower arm assemblies 102, 106 (e.g., in tandem) to control the respective upper and lower moments. In other embodiments, the actuation system 154/156 can be a continuous mass transfer system (e.g., in the form of an unevenly weighted chain, transferable fluid, etc.) configured to transfer a mass from an off-arm location to a desired position on the respective upper and lower arm assemblies 102, 106. In embodiments, the actuation system 154, 156 can be adjusted manually via a user or clinician, or the actuation system 154, 156 can be automatically driven (e.g., via one or more motors or actuators 158, 160).
[0055] Various examples of sliding mass systems are depicted in
[0056] With reference to
[0057] With reference to
[0058] With reference to
[0059] Various examples of continuous mass transfer systems are depicted in
[0060] With reference to
[0061] With reference to
[0062] With reference to
[0063] Various embodiments of systems, devices, and methods have been described herein. These embodiments are given only by way of example and are not intended to limit the scope of the claimed inventions. It should be appreciated, moreover, that the various features of the embodiments that have been described may be combined in various ways to produce numerous additional embodiments. Moreover, while various materials, dimensions, shapes, configurations and locations, etc. have been described for use with disclosed embodiments, others besides those disclosed may be utilized without exceeding the scope of the claimed inventions.
[0064] Persons of ordinary skill in the relevant arts will recognize that the subject matter hereof may comprise fewer features than illustrated in any individual embodiment described above. The embodiments described herein are not meant to be an exhaustive presentation of the ways in which the various features of the subject matter hereof may be combined. Accordingly, the embodiments are not mutually exclusive combinations of features; rather, the various embodiments can comprise a combination of different individual features selected from different individual embodiments, as understood by persons of ordinary skill in the art. Moreover, elements described with respect to one embodiment can be implemented in other embodiments even when not described in such embodiments unless otherwise noted.
[0065] Although a dependent claim may refer in the claims to a specific combination with one or more other claims, other embodiments can also include a combination of the dependent claim with the subject matter of each other dependent claim or a combination of one or more features with other dependent or independent claims. Such combinations are proposed herein unless it is stated that a specific combination is not intended.
[0066] Any incorporation by reference of documents above is limited such that no subject matter is incorporated that is contrary to the explicit disclosure herein. Any incorporation by reference of documents above is further limited such that no claims included in the documents are incorporated by reference herein. Any incorporation by reference of documents above is yet further limited such that any definitions provided in the documents are not incorporated by reference herein unless expressly included herein.
[0067] For purposes of interpreting the claims, it is expressly intended that the provisions of 35 U.S.C. § 112(f) are not to be invoked unless the specific terms “means for” or “step for” are recited in a claim.