DEVICES AND METHODS TO HARVEST ELECTRICAL ENERGY FROM ELECTROMOTIVE FORCE
20230338169 · 2023-10-26
Assignee
Inventors
- Chelsie K. Rodgers (Loma Linda, CA, US)
- Abraham Castillo (Loma Linda, CA, US)
- Michael Davidson (Loma Linda, CA, US)
Cpc classification
International classification
Abstract
A device for harvesting electrical energy from movement of a prosthetic limb. The device including a generator and a controller. The generator adapted to attach to a prosthetic limb. The generator comprising a magnetic linear motor that is configured to generate electrical energy in response to movement of a portion of the prosthetic limb. The controller is electrically connected to the generator and configured to provide electrical energy to a power supply of the prosthetic limb.
Claims
1. A device to harvest electrical energy from movement of a prosthetic limb, the device comprising: a generator adapted to attach to a prosthetic limb, the generator comprising a first motor configured to generate electrical energy in response to movement of a portion of the prosthetic limb; and a controller electrically connected to the generator, the controller configured to provide electrical energy to a power supply of the prosthetic limb.
2. The device according to claim 1, wherein the controller is configured to charge the power supply of the prosthetic limb.
3. The device according to claim 1, wherein the first motor is configured to be disposed within the portion of the prosthetic limb.
4. The device according to claim 1, wherein the first motor comprises: a hollow tubular body; at least one coil of wire wrapped about the body; and a first magnet slidably disposed within the body, the first magnet configured to slide within the body and through the at least one coil of wire in response to movement of the portion of the prosthetic limb such that electrical energy is generated in the at least one coil of wire.
5. The device according to claim 4, wherein the first magnet is configured to slide within the body during a swing phase of a human gait.
6. The device according to claim 4, wherein the first motor comprises: a first end cap closing a first end of the body; a second end cap closing a second end of the body opposite the first end; a second magnet disposed in the first end cap; and a third magnet disposed in the second end cap, the second magnet and the third magnet oriented such that polarities thereof oppose a polarity of the first magnet slidably disposed therebetween.
7. The device according to claim 6, wherein the first magnet, the second magnet, or the third magnet comprise a neodymium magnet.
8. The device according to claim 4, wherein the first motor comprises: a first end cap closing a first end of the body, the first end cap including a first bumper, the first bumper secured to the first end cap and disposed within the body; and a second end cap closing a second end of the body opposite the first end, the second end cap including a second bumper, the second bumper secured to the second end cap and disposed within the body, the first bumper and the second bumper configured to engage the first magnet.
9. The device according to claim 4, wherein the at least one coil of wire forms four separate coils of wire wrapped about the body, the four separate coils being in electrical communication with one another and spaced equidistant along the body.
10. The device according to claim 3, wherein the first motor is configured to generate electrical energy in the form of alternating current.
11. The device according to claim 10, wherein the controller is configured to convert the alternating current from the generator to direct current and to provide the direct current to the power supply of the prosthetic.
12. The device according to claim 11, wherein the controller comprises an electrical storage medium configured to receive and store electrical energy from the first motor, the electrical storage medium configured to output stored electrical energy to the power supply of the prosthetic limb.
13-16. (canceled)
17. A prosthetic limb comprising: a first portion; a power supply; and a generator comprising: a first motor configured to generate electrical energy in response to movement of the first portion; and a controller electrically connected to the generator, the controller configured to provide electrical energy to the power supply.
18. The prosthetic limb according to claim 17, wherein the first motor is a magnetic linear motor or a piezo-electric motor.
19. The prosthetic limb according to claim 17, wherein the first motor is disposed within the first portion.
20. The prosthetic limb according to claim 17, wherein the generator comprises a second motor configured to generate electrical energy in response to movement of the prosthetic limb.
21. The prosthetic limb according to claim 20, wherein the first motor and the second motor are disposed in the first portion.
22. The prosthetic limb according to claim 20, further comprising a second portion, the second motor configured to generate electrical energy in response to movement of the second portion of the prosthetic limb.
23. The prosthetic limb according to claim 22, further comprising a foot, the second portion being a heel of the foot.
24. The prosthetic limb according to claim 22, further comprising a leg segment, the first portion being a section of the leg segment.
25-29. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the disclosure and are not intended as a definition of the limits of the disclosure. For purposes of clarity, not every component may be labeled in every drawing. In the following description, various embodiments of the present disclosure are described with reference to the following drawings, in which:
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DETAILED DESCRIPTION
[0045] The present disclosure will now be described more fully hereinafter with reference to example embodiments thereof with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. These example embodiments are described so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Features from one embodiment or aspect can be combined with features from any other embodiment or aspect in any appropriate combination. For example, any individual or collective features of method aspects or embodiments can be applied to apparatus, product, or component aspects or embodiments and vice versa. The disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. As used in the specification and the appended claims, the singular forms “a,” “an,” “the,” and the like include plural referents unless the context clearly dictates otherwise. In addition, while reference may be made herein to quantitative measures, values, geometric relationships or the like, unless otherwise stated, any one or more if not all of these may be absolute or approximate to account for acceptable variations that may occur, such as those due to manufacturing or engineering tolerances or the like.
[0046] Generally, the devices disclosed herein relate to capturing electrical energy generated by an electromotive force to operate a medical device or store electrical energy for later use. Electromotive Force (EMF), which may be measured in volts, is the electrical action produced by a non-electrical source. For example, EMF may be movement of the human body captured by a generator and converted into electrical energy. Some of the generators disclosed herein utilize electromagnetic induction, which involves moving a magnet through the middle of a wire coil to generate an electrical current in the wire. The current generated flows in the direction that the magnet moves such that an alternating current is generated as the magnet moves back and forth through the coil(s). In various embodiments, the generators may be incorporated into or retrofitted to a prosthetic limb such that movement of the limb causes movement of the magnets relative to one or more coils to generate electrical energy in the form of alternating current (AC).
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[0049] The housing, for example, may be made from a hollow tubular body 112 enclosed on its ends with end caps 114 attached thereto. The end caps 114 may be affixed or bonded to the body 112 or may be removably attached to the body 112 (e.g., threadably attached). The end caps 114 secure the magnets 116 within the body 112 such that the magnets 116 are prevented from exiting the tubular body 112. The body 112 and/or end caps 114 may be made of polyvinyl chloride (PVC) or other polymeric materials. In some embodiments, the body 112 and/or the end caps 114 may be made from other non-metallic materials. The diameter and length of the tubular body 112, and thus the generator 110 overall, will vary to suit a particular application (e.g., type of prosthesis and size of prosthesis). In some embodiments, the body 112 may have a length of 3 inches to 24 inches, alternatively 6 inches to 12 inches. In some embodiments, the tubular body 112 and end caps 114 may have a nominal diameter of 0.25 inches to 2 inches, alternatively 0.5 inches. In the embodiments shown, the tubular body 112 has a circular cross-sectional shape; however, the cross-sectional shape of the tubular body 112 may vary to suit a particular application (e.g., location within the prosthesis, mounting requirements, etc.) and may include, but not be limited to, rectangular, trapezoidal, square, hexagonal, or oval.
[0050] The generator 110 includes at least one wire coil 118 wrapped around the tubular body 112. In the embodiment shown, a single wire is wrapped around the body 112 to form four (4) coils 118 that are spaced substantially equidistant apart. The generator 110 may include a range of 1 to 10 coils 118. The coils 118 may be formed of a single wire or multiple wires. In some embodiments, a single coil 118 may include multiple wires that are wrapped around the tubular body 112 together. The specific number of coils 118, the number of wires, and the spacing therebetween may vary to suit a particular application, with the number of coils 118 and length of the wire influencing the voltage generated. In various embodiments, the coils are formed from a 22 or 32 gauge enameled copper magnet wire that shields the copper wire from the elements. The enameled copper magnet wire may allow for better flow of electrons. The enameled copper magnet wire may require less insulation such that a magnetic field may be improved compared to a non-enameled copper magnet wire. The enamel may be removed as necessary with a fine grit file.
[0051] As shown in
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[0053] The storage device (or medium) 126 of the controller 120 may take on various forms and is generally configured to receive electrical energy in the form of direct current from the rectifier 124. In some embodiments, the storage device may be a battery mount (e.g., configured for receiving one or more AA batteries) to which a battery may be attached. In various embodiments, the storage device 126 is a Ni—Cd 850 mAh (1.2 v) AA rechargeable battery. In embodiments, the storage device 126 is a capacitor soldered to the circuit board 122. The wiring 128 may be standard 22-gauge wire soldered to the enameled copper wire to transfer the electrical energy from the generator 110 to the bridge rectifier 124 and it may be soldered to the hot (power) and the neutral wire, and flow from positive and negative on the bridge rectifier, to the storage device 126.
[0054] In some embodiments, the controller 120 may include a display or other means of informing a user of the status of the device (e.g., an intelligent user interface that may incorporated into the prosthesis or provided via an application program on a smart phone). For example, an OHM meter may be used to indicate the current amount of voltage available in the storage device 126.
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[0058] The main structural support for the prosthesis is called a pylon 206. The pylon 206 is the internal frame or skeleton of the prosthetic limb and is typically formed of metal rods or composites such as carbon fiber composites. The pylon 206 is typically enclosed by a cover made from a foam-like material that may be shaped and colored to match the recipient's skin tone to give the prosthetic limb a more lifelike appearance. Lastly, the prosthesis 202 includes a foot 207. The prosthesis 202 may include other components as needed, such as a suspension system, which may attach the prosthetic limb to the body. Depending on the type of limb, the devices (or portions thereof) described herein may be connected to the pylon 206 or the foot 207.
[0059] In order to further describe operation of an embodiment of the device 100, the normal human gait cycle, which will provide the electromotive force, is described herein. Generally, the human gait refers to the locomotion achieved through the movement of a person's limbs and is defined as bipedal, biphasic forward propulsion of the center of gravity of the human body, in which there are alternating sinuous movements of different segments of the body. With respect to a person's legs, in one instance the initial contact begins with foot fall (i.e., when the foot touches the ground) followed by a loading phase, where a person's weight is rapidly transferred onto the extended leg. This is the first period of double limb support. Next, the person's body is progressing over a single stable limb (i.e., mid-stance), followed by the body moving ahead of the leg on the ground, while the weight is being transferred to the forefoot (i.e., terminal stance). Swing limb advancement follows, where the leg is unloaded, the foot is up off of the ground, and the leg and foot are moved from behind the body to the front, taking the progressional step. The various swing phases are as follows: (a) pre-swing is the rapid de-weighting (unloading) of the leg on the ground, while the weight is shifting to the contralateral leg (i.e., the second period of double limb support); (b) initial swing is the start of advancement of the upper leg (thigh), where the foot is moving up and off of the floor; (c) mid swing involves the continued advancement of the upper leg as the knee starts to move into extension and the foot clears the ground; and (d) terminal swing where the knee comes to full extension and the leg prepares to make contact with ground.
[0060] With additional reference to the device 110 of
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[0062] The controller 320 in
[0063] In various embodiments, the device 300 may include additional components and functionalities. For example, in some embodiments, multiple generators 310 may be incorporated into the prosthesis 302. In some embodiments the device 300 may include 1, 2, 3, or more generators 310. In certain embodiments, a single generator 310 may include multiple motors. For example, a single generator 310 may include 1, 2, 3, or more motors. In embodiments, a piezo-electric generator 356 may replace or be used in addition to the magnetic linear generator 310. In some embodiments, the magnetic linear generator 310 generates electrical energy during the swing phase of the gait, while the piezo-electric generator generates electrical energy during foot fall (e.g., located in the heel such that it is impacted during the loading phase). In addition, the device 300 may include a microprocessor configured to control one or more functionalities of the device 300 or prosthesis 302, an indicator for displaying or transmitting information related to a status of the device 300 or prosthesis 302, or a mechanism that may be used to adjust the device 300 (e.g., voltage regulation).
[0064] With reference to
[0065] The magnetic linear motor 1110 includes a body 1112, a coil 1118, and end caps 1114. The body 1112 may be a single monolithic or unitary element or may be formed of one or more parts that are joined together. The body 1112 includes a generally cylindrical tube 1212 that extends the length of the of the body 1112. The cylindrical tube 1212 is hollow such that a passage 1214 is defined therethrough.
[0066] The cylindrical tube 1212 may include a lip 1216 in each end portion thereof that is configured to secure a respective one of the endcaps 1114 thereto. The body 1112 may include one or more flanges 1218 that are disposed about the body 1112 adjacent a receiver 1222 on an outer surface of the body 1112. As shown, the body 1112 includes a pair of flanges 1218 that define a receiver 1222 therebetween about the outer surface of the body 1112. In some embodiments, the body 1112 includes multiple pairs of flanges 1218 with each pair defining a receiver 1222 therebetween. In certain embodiments, two pairs of flanges 1218 may also define a receiver 1222 therebetween such that two pairs of flanges 1218 (e.g., four flanges 1218) define a total of three receivers 1222. The body 1112 may include between 0 and 8 flanges 1218 and in some embodiments, the body 1112 may include more than eight flanges 1218. The lips 1216 and the flanges 1218 may be integrally, unitarily, or monolithically formed with the tube 1212. In particular embodiments, the lips 1216 or the flanges 1218 may be welded, adhered, or bonded to the tube 1212. In some embodiments, the lips 1216 or the flanges 1218 may be joined to the tube 1212 by one or more fasteners.
[0067] The coil 1118 is formed of wire that is wrapped around or about the body 1112. As shown, the magnetic linear motor 1110 includes a single coil 1118 wrapped around or about the body 1112 that is disposed in a receiver 1222 adjacent a flange 1218 or between a pair of flanges 1218. The wire forming the coil 1118 may be a single wire or may be multiple wires that are electrically coupled to one another. The wire forming the coil 1118 may be a copper wire and in certain embodiments, may be an enameled copper magnet wire. The wire may be a 22 or 32 gauge wire that is coated or uncoated. The coil 1118 may include leads 1119 that extend from the coil 1118 and electrically connect the coil 1118 to other components of a generator. In particular embodiments, one of the leads 1119 of the coil 1118 may extend from the coil 1118 to another coil 1118 and the other lead 1119 of the coil 1118 may extend to a controller of the generator, both of the leads 1119 of the coil 1118 may extend to a controller of the generator, or one leads 1119 of the coil 1118 may extend to another coil 1118 and the other lead 1119 of the coil 1118 may extend to still another coil 1118. It is contemplated that the magnetic linear motor 1110 may include between 1 and 4 coils 1118 and in some embodiments, may include more than 4 coils.
[0068] The one or more of the flanges 1218 may define a cutout 1219 that allow one or both of the leads 1119 to pass through the flange 1218. The cutout 1219 may allow for the lead 1119 to extend from the coil 1118 adjacent or along the outer surface of the body 1112.
[0069] The end caps 1114 are secured to the ends of the body 1112 such that the passage 1214 is closed. In some embodiments, the end caps 1114 seal the passage 1214. The end caps 1114 may interact with the lips 1216 to secure to the body 1112. Additionally or alternatively, the end caps 1114 may be adhered, bonded, or welded to the body 1112 at the lips 1216. In certain embodiments, the end caps 1114 may include a fastener to secure the end caps 1114 to the ends of the body 1112.
[0070] The magnetic linear motor 1110 further includes a magnet 1140 that is disposed within passage 1214 of the body 1112. The end caps 1114 are configured to secure the magnet 1140 within the passage 1214 while allowing the magnet 1140 to freely slide through the passage 1214 such that the magnet 1140 passes through the coil 1118. The magnet 1140 may be similar to the magnet 116b detailed above. As such, the magnet 1140 will not be detailed herein for brevity.
[0071] One or both of the end caps 1114 may include a bumper 1224 that is disposed within the passage 1214 and secured to the respective end cap 1114. The end cap 1114 may define an opening that receives a portion of the bumper 1224 therethrough to secure the bumper 1224 to the end cap 1114. The bumpers 1224 are configured to absorb mechanical energy as the magnet 1140 engages the bumper 1224 and urge the magnet 1140 away from the end cap 1114 to which the bumper 1224 is secured and towards the other bumper 1224 such that the magnet 1140 passes through the coil 1118. The bumpers 1224 may include a spring portion that elastically deforms and stores mechanical energy as it deforms and releases the storage mechanical energy to urge the magnet 1140 towards the opposite bumper 1224 as the bumper 1224 returns to its original shape. The bumpers 1224 may function in a manner similar to the second and third magnets detailed above.
[0072] In a manner similar to the magnetic linear motor 110, as the magnet 1140 passes through the coil 1118, the magnet 1140 induces electrical energy in the coil 1118 that passes to a controller in the form of alternating current. The body 1112 may be attached to or disposed within a prosthetic limb such that the magnet 1140 slides within the passage 1214 of the body 1112 in response to movement of the prosthetic limb. For example, the magnet may slide within the passage 1214 as the prosthetic limb is in a “swing” portion of a human gait as detailed above.
[0073] As noted above, it is within the scope of this disclosure that the magnetic linear motor 1110 may be used in conjunction with or as a replacement for the magnetic linear motor 110 detailed above. Specifically, the magnetic linear motor 1110 may be used with the device 100, 300, the controller 120, the prosthesis 202, and/or the methods detailed herein.
[0074] Having now described some illustrative embodiments of the disclosure, it should be apparent to those skilled in the art that the foregoing is merely illustrative and not limiting, having been presented by way of example only. Numerous modifications and other embodiments are within the scope of one of ordinary skill in the art and are contemplated as falling within the scope of the disclosure. In particular, although many of the examples presented herein involve specific combinations of method acts or system elements, it should be understood that those acts and those elements may be combined in other ways to accomplish the same objectives.
[0075] Furthermore, those skilled in the art should appreciate that the parameters and configurations described herein are exemplary and that actual parameters and/or configurations will depend on the specific application in which the systems and techniques of the disclosure are used. Those skilled in the art should also recognize or be able to ascertain, using no more than routine experimentation, equivalents to the specific embodiments of the disclosure. It is, therefore, to be understood that the embodiments described herein are presented by way of example only and that, within the scope of any appended claims and equivalents thereto; the disclosure may be practiced other than as specifically described.
[0076] The phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. As used herein, the term “plurality” refers to two or more items or components. The terms “comprising,” “including,” “carrying,” “having,” “containing,” and “involving,” whether in the written description or the claims and the like, are open-ended terms, i.e., to mean “including but not limited to.” Thus, the use of such terms is meant to encompass the items listed thereafter, and equivalents thereof, as well as additional items. Only the transitional phrases “consisting of” and “consisting essentially of,” are closed or semi-closed transitional phrases, respectively, with respect to any claims. Use of ordinal terms such as “first,” “second,” “third,” and the like in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish claim elements.