Mechatronic biomedical dynamometer for evaluation of muscle strength of the hand

Abstract

Biomedical mechatronic dynamometer for evaluating the effects of leprosy. The present invention relates to a biomedical mechatronic dynamometer capable of measuring and generating information on the following grip strengths: palmar, pulp-to-pulp pinch, tripod pinch, lateral pinch, and also time-varying force in the range of 0 to 700 N. The information produced by the forces is processed in a microcomputer containing two software programs responsible for the user-friendly numerical and graphical processing and presentation of the force behaviors over time. Another relevant feature is that the invention is capable of generating real-time information that can be transmitted over long distances via wired or wireless communication networks, allowing the physician to analyze and make a diagnosis at the same time as the examination is performed.The dynamometer allows for adjusting the spacing between the supports where pressure sensors are located and the palm support, accommodating any hand size. Finally, the dynamometer provides simultaneous force measurements, facilitating the early diagnosis of diseases and aiding the healthcare professional's decision-making. Ultimately, the processed information can contribute to an accurate diagnosis and appropriate treatment over a period of time.

Description

[001] The present invention relates to a mechatronic biomedical dynamometer capable of accurately measuring and evaluating the effects of the following gripping forces: palmar, pulp-to-pulp pinch, tripod pinch, lateral pinch, and also force varying over time, applied both by the palm of the hand and by the fingers of people suspected of having leprosy infections or already diagnosed with the disease.

[002] Unlike conventional biomedical dynamometers, the current dynamometer invention allows obtaining numerical results regarding intensities, plotting graphs and analyzing the behavior of forces in relation to time.

[003] The invention allows for early diagnosis of diseases that cause degeneration of human physical capacity and that affect the hand, such as: arthritis, arthrosis, stroke (CVA) and, especially, leprosy, assisting the health professional in defining, evaluating, diagnosing the disease and also the duration of treatment.

[004] The present biomedical dynamometer was enabled to allow the application of forces in the range of 0 to 700 N. This equipment consists of three fundamental parts, namely: the mechanical structure of the dynamometer ring where the forces are applied, electronic circuits where the strain sensors are attached, electronic circuits for signal conditioning and also for signal conversion, in addition to two software programs, one containing Artificial Intelligence techniques that allows processing and the other software that presents the information in a user-friendly way, performs the storage and transmission of information. Petition 870260000282, dated 03 / 01 / 2026, page 13 / 25 2 / 10

[005] In the mechanical structure of the dynamometer ring (2), the palmar grip force is applied simultaneously to one of the desired and already mentioned pinch grip force types (6). This is achieved by placing the palm of the hand on the support (6) which is fixed to the lower support (5) of the structure while the four opposing fingers are placed individually on each of the pressure sensors (7), fixed to the upper support (4). In this condition, the application of forces will allow measuring their intensities and obtaining individually the behaviors graphically over time.

[006] The lower support (5) can be replaced by other support models whose supports (6) have an ergonomic shape, taking into account the presence of lesions or other anomalies in the palm of the hand or fingers.

[007] The spacing between the upper support (4) and the lower support (5) can be adjusted appropriately, taking into account the dimensions of the user's hand. This is because the height of the screws (3) supporting the upper support (4) is adjustable by means of nuts and washers (1).

[008] The electronic circuits used are of two types to highlight: the first type are signal conditioning circuits (9) and (10) designed to process (amplify, filter, modulate) analog signals generated by the sensors while the second type refers to a data acquisition board (11) that converts the processed analog signals into digital signals.

[009] The first signal conditioning circuit (10) was used to process the analog signal generated by the strain gauges (8) that were fixed directly to the mechanical structure of the dynamometer ring. The second signal conditioning circuit (9) was used to individually process the analog signals generated by the pressure gauges (7) that were fixed on the upper support (4). In the case of the data acquisition board (11), it is responsible for individually converting the analog signals from the two circuits. Petition 870260000282, dated 03 / 01 / 2026, page 14 / 25 3 / 10 signal conditioning (9) and (10) in digital signals that are sent to a microcomputer via a wired or wireless communication network.

[010] The third part refers to the development of two software programs, one using Artificial Intelligence techniques to process the information, and the other responsible for analysis and presentation in a user-friendly interface, both numerically and graphically, as well as allowing the storage of information produced by each user during use. This presentation of information on the computer monitor is carried out through a user-friendly interface developed with free software.

[011] The biomedical dynamometer invention presented above is capable of generating numerical and graphical information on different forces, allowing healthcare professionals to accurately diagnose and adopt treatments and monitor treatment progress, as well as enabling clinics and hospitals to utilize an indispensable resource. State of the art

[012] Biomedical dynamometers are devices known for having mechanical structures that allow the hand to be accommodated and for manual forces to be applied, causing displacements or deformations. These effects are generally captured by sensors that produce an electrical signal related to the physical effort exerted.

[013] Biomedical dynamometers generally measure the intensity of handgrip strength in order to produce information for the health field and thus allow for physical treatment, etc. These dynamometers are characterized by having only a mechanical structure or by having an electromechanical structure that can generate an analog or analog-digital signal whose intensity is presented by means of an analog or digital display.

[014] In the case of a purely mechanical dynamometer, it is characterized by having gears that rotate or springs that deform with the application of force. Petition 870260000282, dated 03 / 01 / 2026, page 15 / 25 4 / 10 and that cause the amplification of the effect generated by the force. The determination of the amplification occurs objectively by means of a pointer that moves along a graduated scale. Electromechanical dynamometers, on the other hand, have piezoelectric, resistive, capacitive, inductive, or fiber optic-based sensors that are fixed to the mechanical structure and respond to the stimulus caused by the intensity of the applied human force. The electrical response of the sensor produces a magnetic force that moves a pointer fixed on a graduated scale. Existing problems

[015] The state of the art shows that biomedical dynamometers in general have several limitations that restrict their application in the health field.

[016] The first limitation is that the dynamometer design is developed to meet the needs of a specific age range, aiming to serve people with limited physical capacity, thus maximizing the sensitivity of the equipment, protecting its mechanical structure and the sensor itself against excessive physical stress that could damage them.

[017] The second limitation refers to the impossibility of replacing the palm and finger supports, which can interfere with the measurements produced by the equipment due to pain caused by the presence of possible lesions or specific anomalies in the hand. In this way, the indicated force does not reflect reality, and the diagnosis and success of the treatment are compromised.

[018] The third limitation is associated with the inability to provide detailed results regarding physical capacity, since this equipment only captures the maximum intensity of the applied force, but does not distinguish the location nor can it produce specific information about how the finger of the hand is being affected. Therefore, the recovery of only one region of the hand can be confused with a complete recovery, leading to the implementation of an inefficient treatment that can worsen the patient's health. Petition 870260000282, dated 03 / 01 / 2026, page 16 / 25 5 / 10 Objectives of the invention (advantages and novelties)

[019] The objective of this invention is to present a mechatronic biomedical dynamometer that does not perform invasive examination and that does not produce any type of cumulative and harmful energy to the organism such as radiation.

[020] The dynamometer has a structure with sufficient mechanical strength and sensitivity to be used by people regardless of age and physical ability, thus eliminating the need for other devices.

[021] The dynamometer has an upper support (4) and a lower support (5) whose spacing between them can be adjusted considering the dimensions of each user's hand. The appropriate spacing can be obtained by adjusting the height of the screws (3) positioned on the mechanical structure of the dynamometer ring by means of nuts and washers (1). This spacing adjustment ensures that spacings are free from methodological errors.

[022] The dynamometer provides three types of information to consider: the first type refers to the production of numerical information relating to the intensities of the applied forces, the second type refers to the production of graphs that demonstrate the behavior of the forces as a function of time, and finally the third type refers to the analysis resulting from the computational processing performed by the implemented Artificial Intelligence technique.

[023] Finally, the device is capable of sending digital signals from the patient over long distances via wired or wireless communication network so that they can be processed and analyzed on a microcomputer during the examination.

[024] With the various information produced by the user using the biomedical dynamometer, this is stored in a database and made available for use by professionals in clinics and hospitals. Petition 870260000282, dated 03 / 01 / 2026, page 17 / 25 6 / 10 News

[025] The novelty refers to the fact that the mechatronic biomedical dynamometer has the ability to produce information on palmar grip strength, pulp-to-pulp pinch, tripod pinch, lateral pinch, and also varying force over time, applied both by the palm of the hand and individually by the fingers. This dynamometer detects physical anomalies that individually affect each finger of the hand and produces numerical and graphical information through software processing that uses Artificial Intelligence techniques. Brief description of the figures

[026] The invention can be better understood with reference to the drawings described below.

[027] Figure 1 shows the invention of the mechatronic biomedical dynamometer in which the dynamometer ring (2), electronic circuits (9), (10) and (11), wired or wireless communication network (12) and microcomputer (13) are highlighted.

[028] The mechanical structure of the dynamometer ring (2) has an oval shape made of brass, although other metals such as steel, iron, aluminum or polymer etc. can be used. The dynamometer ring (2) has two thin regions that concentrate the deformations and where the strain sensors (8) are fixed, which generate signals that are processed by the signal conditioning circuit (10).

[029] Considering the dimensions of the hand, the spacing between the upper support (4) in which the pressure sensors (7) are fixed and the lower support (5) in which the support (6) for the palm of the hand or fingers is fixed can be conveniently adjusted. This spacing adjustment is obtained by changing the height of the screws (3) by adjusting the nuts and washers (1).

[030] Considering the presence of a lesion located on the palm of the hand or fingers, the inadequate support (6) can be replaced with another that is ergonomically adequate. To effect the change it is necessary to remove the nuts and washers (14). Petition 870260000282, dated 03 / 01 / 2026, page 18 / 25 7 / 10

[031] The simultaneous application of pinch gripping forces on the pressure sensors (7) produces analog signals related to the intensities of the forces applied by the fingers. These analog signals are processed by the signal conditioning circuit (9).

[032] The analog signals generated by the signal conditioning circuits (9) and (10) are individually converted into digital signals on the data acquisition board (11), transmitted via communication network (12) and finally processed and analyzed on the microcomputer (13).

[033] Figure 2 shows the calibration curves for both loading and unloading. Initially, standardized masses of 10 kg were loaded, in the range of 0 to 70 kg, using a basket suspended from the upper support (4) in order to stimulate the strain sensors (8). In the opposite direction, the 10 kg masses were gradually unloaded in the range of 70 kg down to 0.

[034] Figure 3 shows the calibration curves for both loading and unloading. Initially, standardized masses of 10 kg were gradually loaded, in the range of 0 to 70 kg, using four identical and individualized baskets that were hung over each of the four pressure sensors (7). In the opposite direction, the 10 kg masses were gradually unloaded in the range of 70 kg down to 0.

[035] Figure 4 shows the response time of the strain sensor (8). This test was performed by abruptly releasing the upper support (4) on which a basket containing standardized masses totaling 30 kg had been hung.

[036] Figure 5 shows the response time of only one pressure sensor (7), since the other pressure sensors are identical and generate identical responses. This response time was obtained by releasing the basket containing the standardized mass of 30 kg. Petition 870260000282, dated 03 / 01 / 2026, page 19 / 25 8 / 10 Detailed description

[037] It is characteristic of the invention to have resources to measure intensities, to show behaviors in graphic form and to record information generated by gripping forces pulp-to-pulp pinch, tripod pinch, lateral pinch and also force varying over time that can be exerted by the palm of the hand and also individually by each finger during the exercises proposed by the health professional.

[038] It is characteristic of the invention to be able to adjust the spacing between the upper support (4) and the lower support (5), taking into account the dimensions of the user's hand, by means of adjusting the height of the screws (3).

[039] It is characteristic of the invention to be able to generate not only the information that current dynamometers are capable of, such as: palmar grip strength, pulp-pulp pinch, tripod pinch, lateral pinch applied by each finger, and also forces varying over time, allowing the location of anomalies in a part of the hand or finger. In addition, it will be possible to obtain the effectiveness of the treatment adopted against leprosy, arthritis, arthrosis and other diseases that cause muscle degeneration.

[040] A characteristic of the invention is that the mechanical body of the dynamometer (2) is made of brass due to the ease of machining and also due to the low acquisition cost compared to other metals. In addition, brass is a metal that has adequate mechanical strength and sensitivity for the project. However, the mechanical structure may be made of other materials such as ceramic, polymer and metal, both natural and synthesized in the laboratory.

[041] The invention features the conversion of analog signals into digital signals, making it possible to send this information over long distances via wired or wireless communication networks, without electromagnetic interference. Petition 870260000282, dated 03 / 01 / 2026, page 20 / 25 9 / 10

[042] A characteristic of the invention is the ability of the biomedical dynamometer to assist in the early diagnosis of patients with leprosy, arthritis, arthrosis and stroke.

[043] A characteristic of the invention is that the biomedical dynamometer has a computational interface developed in free software, and another software, in which an Artificial Intelligence technique has been embedded, is able to process the information generated by the applied forces, produce numerical results regarding the intensities and graphs relating to them.

[044] The invention of the mechatronic biomedical dynamometer is characterized by having three fundamental parts: mechanical structure, electronic circuits and a microcomputer containing two software programs, one containing Artificial Intelligence technology that allows processing and the other software that presents the information in a user-friendly way, performs storage and transmission of information.

[045] The mechanical structure of the invention consists of an oval-shaped dynamometer ring where sensors have been fixed in the thinner regions to capture the deformation and produce an analog signal related to the applied gripping forces.

[046] The mechanical structure also has a lower support (5) where a support (6) is fixed to accommodate the fingers or palm of the hand, while four identical pressure sensors (7) are fixed to the upper support (4), aiming to individually measure the pinch grip forces applied by the fingers of the hand. The two supports (4) and (5) are thin and are developed in material of good mechanical resistance, which may be metal, polymer, etc. The spacing between the supports (4) and (5) can be altered according to the dimensions of the user's hand, as the screws (3) can have their height modified by adjusting the nuts and washers (1). Petition 870260000282, dated 03 / 01 / 2026, page 21 / 25 10 / 10

[047] The support (6) can be replaced by another that has an ergonomic shape and comfortable material for the fingers of the hand, considering the presence of injury or anomaly in one or more fingers. The replacement of the support (6) occurs by removing the screws and washers (14).

[048] The electronic circuits section begins with the presence of the strain gauges (8) and the pressure gauges (7). The electrical connections of the strain gauges (8) were made in order to stabilize the analog signal produced in relation to temperature and humidity. This analog signal is filtered, amplified and modulated by the signal conditioning circuit (9) whose analog response is converted into a digital signal by means of a data acquisition board (11). This digital signal is then transmitted via the wired or wireless communication network (12) to a microcomputer containing two software programs, one containing Artificial Intelligence techniques that allows processing and the other software that performs the numerical and graphical presentations of the information in a user-friendly way, storage and transmission of the information.

[049] In the case of pressure sensors (7), the generated analog signals are individually filtered, amplified and modulated by another signal conditioning circuit (10). This circuit has four independent inputs and four outputs, and the analog signals produced are converted into digital signals by means of a data acquisition board (11) which has five inputs and five outputs. These digital signals are in turn transmitted through the wired or wireless communication network (12) to a microcomputer that performs the processing and obtains numerical and graphical information regarding the behavior of the forces.

Claims

1. BIOMEDICAL MECHATRONIC DYNAMOMETER FOR EVALUATING HAND MUSCLE STRENGTH, characterized by comprising: - a mechanical structure based on an oval-shaped dynamometer ring (2), equipped with two thin regions configured to concentrate mechanical deformations, said ring being associated with an upper support (4) and a lower support (5), whose relative positions are adjustable by means of screws (3), nuts and washers (1); - a support (6) intended for the palm of the hand or the user's fingers; - deformation sensors (8) fixed to the thin regions of the dynamometer ring (2) and four pressure sensors (7) fixed to the upper support (4); - independent signal conditioning circuits (10) electrically connected to the deformation sensors (8), configured to compensate for thermal and environmental effects;- independent signal conditioning channels (9) associated with each of the four pressure sensors (7), allowing the individualized acquisition of electrical signals corresponding to the gripping forces applied by different fingers of the hand; - a data acquisition board (11) configured to collect the conditioned analog signals and convert them into digital signals; - a communication network (12), wired or wireless, configured to transmit, in real time, the data corresponding to the forces exerted by the user; Petition 870260057680, dated 06 / 13 / 2026, page 8 / 9; 2 / 2 - and a microcomputer (13) operating connected to the data acquisition board, running two distinct software programs, one of which is configured for processing digital signals using Artificial Intelligence techniques to assess the effects of leprosy, and the other configured for analysis, graphical and numerical presentation, storage and transmission of the information obtained through a graphical interface.

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