Wearable human upper limb motion energy harvester

Abstract

The application discloses a wearable human upper limb motion energy harvester, which comprises a base, a cover plate, a belt transmission mechanism, a gear transmission mechanism, a spiral one-way excitation mechanism, a fixed beam and a rotor power generation module; the top wall of the base is fixed with the cover plate, and the cavities of the base and the cover plate are sequentially provided with a high-speed shaft, a low-speed shaft and a gear shaft of a fixed gear from left to right along the vertical direction; the spiral one-way excitation mechanism and the rotor power generation module are coaxially and spacedly connected to the high-speed shaft; the gear shaft of the low-speed shaft is fixedly connected with the inner ring of the bearing installed in the cover plate and the base at both ends; the driving wheel and the driven gear are sleeved and fixed on the low-speed shaft and are fixedly connected at both ends; the high-speed shaft is fixedly connected with the cover plate and the base at both ends, and the gear shaft is fixedly connected with the base at the lower end; and the energy collection efficiency can be improved.

Description

Technical Field

[0001] This invention relates to the mechanical structure of a human energy harvester, and more particularly to a wearable human upper limb motion energy harvester. Background Technology

[0002] Wearable electronic devices have broad application prospects in environmental monitoring, human-computer interaction interfaces, and human health monitoring. However, the use of traditional battery power faces practical problems such as the need for regular battery replacement, large battery size, and environmental pollution, making power supply a significant factor restricting the development of these electronic devices. Therefore, research on self-powered technology is urgently needed, which is essentially human energy harvesting. Human motion energy is characterized by low frequency and periodic non-harmonicity, while the vibration sources of traditional energy harvesters are characterized by high frequency and resonance. This makes it difficult for traditional energy harvesters to achieve ideal results in human motion energy harvesting. In summary, existing energy harvesters in the field of human motion energy harvesting suffer from the problems of ineffective harvesting of low-frequency human motion energy and low energy harvesting efficiency. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a wearable human upper limb motion energy harvester that can improve energy harvesting efficiency.

[0004] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0005] This invention discloses a wearable upper limb motion energy harvester, comprising a base, a cover plate fixed to the top wall of the base, and a high-speed shaft, a low-speed shaft, and a gear shaft with a fixed gear arranged vertically from left to right in the cavity between the base and the cover plate. A helical unidirectional excitation mechanism, a rotor structure of a rotor power generation module, and a limiting block are coaxially and spaced vertically on the high-speed shaft. The upper and lower ends of the gear shaft of the low-speed shaft are fixedly connected to the inner rings of bearings installed in the cover plate and the base, respectively. A driving wheel and a driven gear are mounted and fixedly connected vertically on the low-speed shaft. The bottom of the high-speed shaft and the gear shaft with the fixed gear are fixed to the base, and the lower end of the gear shaft is fixedly connected to the base.

[0006] A fixed beam is fixed at one end, pressing against a fixed gear, and the other end is fixedly connected to the base. The fixed gear meshes with the driven gear, and the ratio of the number of teeth of the fixed gear to the number of teeth of the driven gear is greater than 1. The fixed beam has a fixed end that can be fixed to a human body. The spiral unidirectional excitation mechanism includes an outer layer with an internally threaded hole in the middle, located above the rotor structure. An external thread is provided on the lower outer wall of the inner layer, and the lower external thread of the inner layer is threadedly connected to the internally threaded hole of the outer layer. A driven wheel is provided on the upper part of the outer layer, and the driven wheel is connected to the driving wheel via a belt. The diameter of the driving wheel is larger than the diameter of the driven wheel. The inner layer and the limiting block are fixedly connected to the base. The rotor structure is rotatably connected to the high-speed shaft. A spring is sleeved on the high-speed shaft between the rotor structure and the limiting block. The upper and lower ends of the spring are fixedly connected to the rotor structure and the limiting block, respectively. The outer layer can move up and down away from the rotor structure or contact the rotor structure and drive the rotor structure to rotate under the action of friction. The stator of the rotor power generation module is installed inside the base.

[0007] The beneficial effects of this invention are:

[0008] This invention incorporates a gear transmission mechanism, a belt transmission mechanism, and a helical unidirectional excitation mechanism to convert low-frequency human motion signals into high-frequency signals using the transmission ratio of the gear and belt transmission mechanisms. Furthermore, the helical unidirectional excitation component transmits the signal to a rotor power generation module, converting mechanical energy into electrical energy. This improves the efficiency of human motion energy harvesting, alleviating the problems of existing energy harvesters' inability to effectively harvest low-frequency human motion energy and the low energy harvesting efficiency in the energy harvesting field, thus enhancing overall energy harvesting efficiency. Attached Figure Description

[0009] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0010] Figure 1 A perspective view of a wearable human upper limb motion capture device provided in an embodiment of the present invention;

[0011] Figure 2 A front view of a wearable human upper limb motion capture device provided in an embodiment of the present invention;

[0012] Figure 3 for Figure 1 A three-dimensional view of the low-speed axis in the energy trap shown;

[0013] Figure 4 for Figure 3 The front view of the low-speed shaft is shown.

[0014] Figure 5 for Figure 1 A three-dimensional view of the high-speed axis in the energy trap shown;

[0015] Figure 6 A perspective view of a helical unidirectional excitation mechanism provided in an embodiment of the present invention;

[0016] Figure 7 This is a schematic diagram of the energy harvester of the present invention worn on a human body;

[0017] Figure 8-1 yes Figure 7 The voltage waveform of the structure shown in the slow-run test is shown.

[0018] Figure 8-2 yes Figure 7 The voltage waveform of the structure shown is obtained from the running experiment. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] As shown in the attached figure, a wearable upper limb energy harvester mechanical structure of the present invention includes a base 8. A cover plate 7 is fixed on the top wall of the base 8. A high-speed shaft, a low-speed shaft 9, and a gear shaft with a fixed gear 3 are arranged vertically from left to right in the cavity between the base 8 and the cover plate. A helical unidirectional excitation mechanism, a rotor structure 5 of a rotor power generation module, and a limiting block are coaxially and spaced vertically on the high-speed shaft. The upper and lower ends of the gear shaft of the low-speed shaft 9 are fixedly connected to the inner rings of bearings installed in the cover plate 7 and the base 8, respectively. A driving wheel 2 and a driven gear 6 are mounted and fixedly connected on the low-speed shaft 9. The upper and lower ends of the high-speed shaft are fixedly connected to the cover plate 7 and the base 8, respectively, and the lower end of the gear shaft is fixedly connected to the base 8.

[0021] One end of the fixed beam 4 presses against the fixed gear 3, which is then fixed by the fixed beam 4. The other end of the fixed beam 4 is fixedly connected to the base 8. The fixed gear 3 meshes with the driven gear 6, and the ratio of the number of teeth on the fixed gear to the number of teeth on the driven gear is greater than 1. The fixed beam has a fixed end that can be fixed to the human body. The effect of this gear transmission mechanism is that a small gear can rotate in a circle around a large fixed gear. The function of the fixed beam is twofold: firstly, it can completely lock the fixed gear, making it fully "fixed," and secondly, it facilitates connection with the human body. The protruding part of the fixed beam can be fixed to the body to better collect energy from human movement. The purpose of the circular rotation design is that after being worn on the human body, as the upper arm swings, the entire mechanism swings around the center of the fixed gear. At this time, the driven gear inside will swing around the fixed gear in a small semi-circular motion.

[0022] The described helical unidirectional excitation mechanism includes an outer layer 10 with an internally threaded hole in the middle, located above the rotor structure. An external thread is provided on the lower outer wall of the inner layer 11, and the lower external thread of the inner layer is threadedly connected to the internally threaded hole of the outer layer. A driven wheel is provided on the upper part of the outer layer, connected to a driving wheel 2 via a belt. The diameter of the driving wheel 2 is larger than the diameter of the driven wheel. The inner layer and the limiting block are fixedly connected to the base. The rotor structure is rotatably connected to the high-speed shaft. A spring is fitted on the high-speed shaft between the rotor structure and the limiting block, with its upper and lower ends fixedly connected to the rotor structure and the limiting block, respectively. The outer layer can move up and down away from the rotor structure or contact the rotor structure, driving the rotor structure to rotate under friction. The stator of the rotor power generation module is installed inside the base 8.

[0023] Because the human upper arm moves in a reciprocating motion, and the inner part of the helical unidirectional excitation mechanism is fixedly connected to the base, the outer part can move up and down in the axial direction of the high-speed shaft, thus achieving a repeated contact and disengagement process with the rotor structure 5. During the process of the outer part of the helical unidirectional excitation mechanism pressing against the rotor structure 5, the friction generated by the contact drives the rotor structure 5 to rotate. Since the direction of rotation is fixed as the outer part of the helical unidirectional excitation mechanism moves away from the rotor structure 5, the helical unidirectional excitation mechanism can achieve unidirectional rotational excitation of the rotor structure 5.

[0024] Preferably, the power generation limiting plate 1 is a circular ring structure. The power generation limiting plate 1 is spaced out and fitted on the outside of the outer layer and located above the rotor structure 5. The edge of the power generation limiting plate is fixed to the circular ring platform protruding from the inner wall of the base 8. The function of the power generation limiting plate is to limit the movement range of the outer layer of the unidirectional excitation mechanism.

[0025] This device transfers the energy from the helical unidirectional excitation mechanism to the rotor power generation module and generates electricity using Faraday's law of electromagnetic induction. The structure of the rotor power generation module can be found in Guo S, Gao S, Jin L, et al. Mechanism, theory and application research of a rotating electromagnetic energy harvester suitable for multi-directional excitation[J]. Journal of Physics, D. Applied Physics: A Europhysics Journal, 2022(8):55.

[0026] Preferably, the edge of the cover plate 7 is detachably connected to the base 8.

[0027] The working principle of this device is as follows:

[0028] like Figure 7As shown, the device is fixed to the upper surface of the shoulder by a fixing beam, and the main structure is fixed to the upper arm by straps. When the human body walks and swings its arm, in the gear transmission mechanism, the base swings, causing the driven gear to revolve around the center of the fixed gear. The driven gear meshes with the fixed gear and rotates on its own axis while revolving. In the belt transmission mechanism, the driving wheel is connected to the driven gear and the low-speed shaft and rotates coaxially and at the same speed. In the belt transmission mechanism, the driving wheel is connected to the outer part of the spiral unidirectional excitation mechanism through a belt. The rotation of the driving wheel causes the outer part of the spiral unidirectional excitation mechanism to accelerate. When the human body swings its arm forward, the outer part of the spiral unidirectional excitation mechanism rotates relative to the inner part of the spiral unidirectional excitation mechanism. Since the two are connected by threads, the distance between the outer part of the spiral unidirectional excitation mechanism and the rotor structure in the rotor power generation module gradually decreases until they are in contact. The two parts come into contact and squeeze each other. When the human body swings its arm backward, the outer part of the spiral unidirectional excitation mechanism and the rotor part of the rotor power generation module rotate rapidly relative to each other. Since the outer part of the spiral unidirectional excitation mechanism and the inner part of the spiral unidirectional excitation mechanism are connected by threads, the outer part of the spiral unidirectional excitation mechanism gradually disengages from the rotor part of the rotor power generation module during rotation. At this time, the rotor structure in the rotor power generation module will continue to rotate due to its own inertia. The above process is repeated when the human body swings its arm back and forth, causing the rotor part of the rotor power generation module to rotate continuously and periodically at high speed. The permanent magnet on the outer ring of the rotor part of the rotor power generation module rotates relative to the coil of the stator part in the base. The permanent magnet and the coil cut magnetic field lines, thereby generating electricity.

[0029] The testing process for this device is as follows:

[0030] The device was worn on the experimenter's right upper arm.

[0031] The rotor generator module's wires are connected to a RIGOL oscilloscope to detect voltage waveform signals.

[0032] Under laboratory conditions, the participants performed two exercise modes: walking and running, and the test results were obtained under both exercise modes.

[0033] The test results showed a consistent alternating current in both walking and running states. Figure 8-1 As shown, during slow-moving operation, the voltage frequency is lower, the peak voltage decreases, and the effective value is lower; for example... Figure 8-2 As shown, during the running process, the voltage frequency is higher, the peak voltage is higher, and the effective value is higher.

[0034] Therefore, it can be concluded that the device can meet the power supply needs of wearable sensors regardless of whether the exercise is running or walking. The more intense the exercise, the higher the power generation efficiency. The generated power can be stored in the energy storage circuit and supplied to other devices. The energy storage circuit can be found in P. Mayer, M. Magno, L. Benini, Energy-positive activity recognition-from kinetic energy harvesting to smart self-sustainable wearable devices[J], IEEE Transactions on Biomedical Circuits and Systems, 2021, 15(5):926-937. Since energy storage is not the inventive point of this invention, it will not be described in detail.

[0035] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and apparatus described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0036] Furthermore, in the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0037] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0038] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A wearable human upper limb motion capture device, characterized in that: The system includes a base (8), a cover plate (7) fixed on the top wall of the base, and a high-speed shaft, a low-speed shaft (9) and a gear shaft of a fixed gear (3) arranged vertically from left to right in the cavity between the base and the cover plate. A spiral unidirectional excitation mechanism, a rotor structure (5) of a rotor power generation module and a limit block are coaxially and spaced on the high-speed shaft. The upper and lower ends of the gear shaft of the low-speed shaft are fixedly connected to the inner rings of the bearings installed in the cover plate and the base, respectively. A drive wheel (2) and a driven gear (6) are mounted and fixed on the low-speed shaft. The drive wheel and the driven gear are fixedly connected vertically. The bottom of the high-speed shaft and the gear shaft of the fixed gear are fixed on the base. The lower end of the gear shaft is fixedly connected to the base. One end of the fixed beam (4) is pressed against the fixed gear, and the other end of the fixed beam is fixedly connected to the base; the fixed gear (3) meshes with the driven gear (6), and the ratio of the number of teeth of the fixed gear to the number of teeth of the driven gear is greater than 1. The fixed beam has a fixed end that can be fixed to the human body. The spiral unidirectional excitation mechanism includes an outer layer (10) with an internal thread hole in the middle. The outer layer is located above the rotor structure. An external thread is provided on the lower outer wall of the inner layer (11). The lower external thread of the inner layer is threaded to the internal thread hole of the outer layer. The upper part is provided with a driven wheel, which is connected to the driving wheel (2) by a belt. The diameter of the driving wheel is larger than that of the driven wheel. The inner part and the limiting block are fixedly connected to the base. The rotor structure is rotatably connected to the high-speed shaft. A spring is sleeved on the high-speed shaft between the rotor structure and the limiting block. The upper and lower ends of the spring are fixedly connected to the rotor structure and the limiting block, respectively. The outer part can move up and down away from the rotor structure or contact the rotor structure and drive the rotor structure to rotate under the action of friction. The stator of the rotor power generation module is installed inside the base.

2. The wearable human upper limb motion capture device according to claim 1, characterized in that: A circular structure power generation limiting plate is spaced outside the outer layer and located above the rotor structure. The edge of the power generation limiting plate is fixed to the circular platform protruding from the inner wall of the base.

3. The wearable human upper limb motion capture device according to claim 1 or 2, characterized in that: The edge of the cover plate is detachably connected to the circular platform of the base.

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