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1.
Artif Organs ; 48(1): 50-60, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37877242

RESUMO

BACKGROUND: Conventional hip disarticulation prostheses (HDPs) are passive devices with separate joint structures, limiting amputees' ability to control and resulting in abnormal gait patterns. This study introduces a new HDP integrating the hip and knee joints for amputees' natural gait. METHODS: The new HDP restores the physiological rotation center of the hip with a remote center of motion (RCM) structure, and simulates the knee motion with a four-bar structure. Nonlinear programming was employed to optimize the hip-knee joint structure. A hybrid multi-objective drive structure with a series-parallel connection was also designed to ensure motion synergy between the hip and knee joints. Finally, a prototype of the prosthesis was tested using the HDP test system. RESULTS: The optimization results demonstrate that the new HDP accurately restores the rotation center of the femur in amputees, with the knee's instantaneous center of rotation (ICR) trajectory closely resembling that of the human knee (Pearson correlation coefficient is 0.999). The study shows that the new HDP achieves a motion reproduction accuracy of over 95% for the human hip joint at walking speeds above 1.5 km/h, 38% higher than conventional prosthesis. Similarly, at the same walking speed, the new HDP replicates the motion of the human knee at 82.89%, surpassing conventional prosthesis by 57.85%. CONCLUSIONS: The new HDP restores symmetry and replicates synergistic movement in amputees' lower limbs, exhibiting superior movement characteristics compared to conventional prostheses. This innovative HDP has the potential to enhance the quality of life for amputees.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Humanos , Perna (Membro) , Qualidade de Vida , Desenho de Prótese , Marcha/fisiologia , Articulação do Joelho/cirurgia , Articulação do Joelho/fisiologia , Fenômenos Biomecânicos , Caminhada/fisiologia
2.
Inorg Chem ; 62(44): 18128-18135, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37881839

RESUMO

Materials with enzyme-like activity have received a lot of attention in the field of tumor catalytic therapy. Here, biocompatible core-shell MOF CSMnP with two valence states of Mn ion, which could process chemodynamic therapy (CDT), was designed and synthesized. Besides, it could also promote a series of catalytic processes in the tumor microenvironment (TME). CSMnP catalyzed endogenous hydrogen peroxide (H2O2) to oxygen (O2) via catalase-like activity and then combined with the outer layer Mn(II)-PBC to convert O2 into superoxide radicals (•O2-), exhibiting oxidase-like activity. Besides, intracellular glutathione (GSH) could be effectively consumed through the glutathione oxidase-like activity of Mn3+. The occurrence of the cascade reactions effectively amplified the enzymatic production to enhance CDT. Furthermore, the therapeutic effect of CSMnP was improved through the loading of cationic drug DOX. The loading capacity was 11.10 wt %, which was 2.2 times that of Mn(III)-PBC (4.95 wt %), and the release of DOX showed a characteristic response. Therefore, the core-shell MOF with enzyme-like activity had a potential application for tumor combination therapy.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Humanos , Catálise , Glutationa , Oxigênio , Neoplasias/tratamento farmacológico , Microambiente Tumoral
3.
Pain Med ; 24(3): 351-361, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36102803

RESUMO

OBJECTIVE: Transcutaneous electrical nerve stimulation (TENS) based on wrist-ankle acupuncture has been shown to relieve pain levels in patients with myofascial pain syndrome (MPS). However, its efficacy is highly subjective. The purpose of this study was to evaluate the feasibility and effectiveness of TENS based on wrist-ankle acupuncture for pain management in patients with MPS from the perspective of cerebral cortex hemodynamics. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: We designed a double-blind, randomized, controlled clinical trial. Thirty-one male patients with MPS were randomly assigned to two parallel groups. The experimental group (n = 16) received TENS based on wrist-ankle acupuncture for analgesic treatment, while the control group (n = 15) did not. The pain was induced by mechanically pressurized at acupoint Jianjing. The multichannel functional near-infrared spectroscopy (fNIRS) equipment was utilized for measuring oxyhemoglobin (HbO) levels in the cerebral cortex during the tasks. RESULTS: After the intervention, visual analog scale (VAS), the activation degree and activation area of pain perception cortices were significantly reduced in the experimental group compared to the baseline values (P < .05). Particularly, Frontopolar Area (FPA), and Dorsolateral Prefrontal Cortex (DLPFC) are highly involved in the pain process and pain modulation. CONCLUSION: Compared to no intervention, TENS based on wrist-ankle acupuncture can be effective in relieving pain in patients with MPS in terms of cerebral cortical hemodynamics. However, further studies are necessary to quantify the analgesic effect in terms of cerebral hemodynamics and brain activation.


Assuntos
Terapia por Acupuntura , Estimulação Elétrica Nervosa Transcutânea , Humanos , Masculino , Tornozelo , Punho , Dor , Terapia por Acupuntura/métodos , Analgésicos , Estimulação Elétrica Nervosa Transcutânea/métodos , Estimulação Elétrica , Córtex Cerebral , Resultado do Tratamento
4.
Artif Organs ; 47(8): 1285-1297, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36869693

RESUMO

BACKGROUND: Existing artificial anal sphincter studies have shown that biomechanical compatibility problem between artificial anal sphincter and rectum caused by long-term morphological changes of the tissue surrounding the implanted prosthesis can lead to device failure or tissue ischemic necrosis. In this article, a mechanical artificial anal sphincter with constant force clamping is designed based on the superelasticity of shape memory alloys, which improved the biomechanical compatibility of implantable artificial anal sphincter. METHODS: Firstly, the anatomical structure and the biomechanical properties of the rectum are analyzed to obtain the size parameters and material parameters of the rectal model. Secondly, a novel artificial anal sphincter with constant force is designed to improve the biomechanical compatibility between the artificial sphincter and the rectum. Thirdly, the static analysis of artificial anal sphincter is carried out by finite element analysis. RESULTS: The simulation results show that the artificial anal sphincter can maintain a constant clamping force of 4 N within a certain variation range of intestinal tissue thickness, which verifies the constant force characteristic of the artificial anal sphincter. The constant clamping force of the artificial anal sphincter to the rectum is 4 N that is greater than the clamping force 3.99 N required to close the rectum, which verifies the effectiveness the artificial anal sphincter. The surface contact stress and the minimum principal stress of the rectum in the clamping state are less than the pressure threshold, which verifies the safety of the artificial anal sphincter. CONCLUSIONS: The novel artificial anal sphincter has better biomechanical compatibility and improves the mechanical match between artificial sphincter and intestinal tissue. This study may provide more reasonable and effective simulation data for in vivo experiments of artificial anal sphincter in future, which may provide theoretical and technical support for further research about clinical application of artificial anal sphincter.


Assuntos
Incontinência Fecal , Esfíncter Urinário Artificial , Humanos , Canal Anal/cirurgia , Reto , Próteses e Implantes
5.
Artif Organs ; 47(11): 1688-1699, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37424277

RESUMO

BACKGROUND: Urinary incontinence is a urinary disorder in which urine leaks out involuntarily. This disorder seriously affects the quality of life of patients. For patients with mild incontinence, conservative treatment and medication may be the ideal treatment modality, but for patients with severe incontinence, an artificial urinary sphincter is currently a better treatment option. METHODS: In order to design an ideal artificial urinary sphincter, this article first searched and collected literature based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses searched strategy by selecting specific subject terms and reviewed the artificial urinary sphincters that are currently in the research stage based on different activation methods. RESULTS: In response to the deficiencies of the existing artificial urinary sphincter, this article discusses the future optimization of the artificial urinary sphincter from three aspects: individual improvement of the artificial urinary sphincter, engineering design elements, and optimization of the artificial urinary sphincter manufacturing process. CONCLUSIONS: The manufacture of an idealized artificial urinary sphincter capable of meeting clinical needs is of great importance to improve the quality of life of patients. However, this approach is a reasonable option to explore and should not be overestimated until further evidence is available.


Assuntos
Incontinência Urinária , Esfíncter Urinário Artificial , Masculino , Humanos , Qualidade de Vida , Prostatectomia/métodos , Incontinência Urinária/cirurgia , Previsões
6.
Artif Organs ; 47(7): 1075-1093, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37114754

RESUMO

BACKGROUND: Urinary incontinence is a common clinical problem in the world today. Artificial urinary sphincter is a good treatment approach for severe urinary incontinence, which is designed to mimic the action of the human urinary sphincter and assist patients to regain urinary function. METHODS: There are many control methods based on artificial urinary sphincter, such as hydraulic control, electromechanical control, magnetic control, and shape memory alloy control. In this paper, the literature was first searched and documented based on PRISMA search strategy for selected specific subject terms. Then, a comparison of artificial urethral sphincters based on different control methods was conducted, and the research progress of magnetically controlled artificial urethral sphincters was reviewed, and their advantages and disadvantages were summarized. Finally, the design factors for the clinical application of magnetically controlled artificial urinary sphincter are discussed. RESULTS: As magnetic control allows for non-contact force transfer and does not generate heat, it is proposed that magnetic control may be one of the more promising control methods. The design of future magnetically controlled artificial urinary sphincters will need a variety of considerations, including the structural design of the device, manufacturing materials, manufacturing costs, and convenience. In addition, validation of the safety and effectiveness of the device and device management are equally important. CONCLUSIONS: The design of an ideal magnetically controlled artificial urinary sphincter is of great importance to enhance patient treatment outcomes. However, there are still great challenges to be faced for the clinical application of such devices.


Assuntos
Incontinência Urinária , Esfíncter Urinário Artificial , Humanos , Incontinência Urinária/cirurgia , Micção , Uretra , Resultado do Tratamento
7.
Artif Organs ; 46(6): 1097-1106, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35060136

RESUMO

BACKGROUND: Fecal incontinence caused by sphincter dysfunction is a difficult medical problem that has not been fully resolved. The artificial anal sphincter provides a new therapeutic strategy for fecal incontinence. In order to solve the biomechanical compatibility problem between the artificial anal sphincter and intestinal tissue in clinical application, a design of constant force artificial anal sphincter was assessed in this paper. METHODS: The constant force properties and safety of this novel device were evaluated by an experiment conducted in pig intestines with various thicknesses. The constant force characteristic of the device was evaluated by the intestinal pressure of the pig intestine. The safety of the device was evaluated by the surface contact stress of the pig intestine clamped by an artificial anal sphincter. RESULTS: The average measured value of the intestinal pressure of the pig intestines with three thicknesses is about 55.3 mm Hg, the maximum pressure difference is 1 mm Hg, and the fluctuation error of constant clamping load is about 1.8%. The constant clamping load fluctuation error of the four measuring points of the pig intestines with three thicknesses is less than 2%. Even if the thickness of the pig intestines is changed, the measured contact stress value is lower than 10 kPa, which may avoid bit damage for the intestinal tissue. CONCLUSIONS: This study demonstrates that the novel artificial sphincter has constant force properties and safety, which prevent ischemic necrosis of soft tissues caused by excessive pressure. Therefore, this study raises the possibility of the long-term efficacy of artificial anal sphincter.


Assuntos
Órgãos Artificiais , Incontinência Fecal , Canal Anal/cirurgia , Animais , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Desenho de Prótese , Ligas de Memória da Forma , Suínos
8.
Pain Pract ; 22(2): 182-190, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34519161

RESUMO

BACKGROUND: As a new technology, electronic wrist-ankle acupuncture (E-WAA) combines the advantages of wrist-ankle acupuncture and transcutaneous electrical nerve stimulation, but the analgesic effect and mechanism need to be clarified. The purpose of this study was to identify the pain modulation caused by E-WAA by evaluating the response of the prefrontal cortex (PFC) from the perspective of neurophysiology. METHODS: Fifty male volunteers (age 25.00 ± 1.05 years) with trapezius myofascial pain syndrome were randomly allocated into intervention group (E-WAA treatment) or sham control group at a 1:1 ratio. An outcome evaluation system was used to induce tenderness on the Jianjing point and record the pain value. A multichannel functional near-infrared spectroscope was used to detect the PFC activation during tenderness before and after treatment to demonstrate the neuromodulation mechanism. A general linear model and t-test (p < 0.05) were used to analyze the difference in the oxyhemoglobin (HbO) concentration and pain value. RESULTS: In the intervention group, the pain value of volunteers decreased significantly (p = 0.017) after E-WAA treatment, whereas there was no statistical difference (p = 0.082) in the sham group. Before treatment, the frontopolar (FP) and dorsolateral prefrontal cortex (DLPFC) were the activation areas of the PFC. The E-WAA treatment then suppressed the activation of the two areas. The HbO concentration of the FP and DLPFC changed from a sharp rise during tenderness to not changing with tenderness stimulation. CONCLUSION: The results demonstrated that the E-WAA have a great analgesic effect. The FP and DLPFC were relative to the analgesia neuromodulation induced by the E-WAA.


Assuntos
Terapia por Acupuntura , Punho , Terapia por Acupuntura/métodos , Adulto , Tornozelo , Eletrônica , Humanos , Masculino , Dor , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(3): 620-626, 2022 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-35788532

RESUMO

At present, the upper limb function of stroke patients is often assessed clinically using a scale method, but this method has problems such as time-consuming, poor consistency of assessment results, and high participation of rehabilitation physicians. To overcome the shortcomings of the scale method, intelligent upper limb function assessment systems combining sensors and machine learning algorithms have become one of the hot research topics in recent years. Firstly, the commonly used clinical upper limb functional assessment methods are analyzed and summarized. Then the researches on intelligent assessment systems in recent years are reviewed, focusing on the technologies used in the data acquisition and data processing parts of intelligent assessment systems and their advantages and disadvantages. Lastly, the current challenges and future development directions of intelligent assessment systems are discussed. This review is hoped to provide valuable reference information for researchers in related fields.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Algoritmos , Humanos , Modalidades de Fisioterapia , Acidente Vascular Cerebral/diagnóstico , Extremidade Superior
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(1): 175-184, 2022 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-35231979

RESUMO

The body weight support rehabilitation training system has now become an important treatment method for the rehabilitation of lower limb motor dysfunction. In this paper, a pelvic brace body weight support rehabilitation system is proposed, which follows the center of mass height (CoMH) of the human body. It aims to address the problems that the existing pelvic brace body weight support rehabilitation system with constant impedance provides a fixed motion trajectory for the pelvic mechanism during the rehabilitation training and that the patients have low participation in rehabilitation training. The system collectes human lower limb motion information through inertial measurement unit and predicts CoMH through artificial neural network to realize the tracking control of pelvic brace height. The proposed CoMH model was tested through rehabilitation training of hemiplegic patients. The results showed that the range of motion of the hip and knee joints on the affected side of the patient was improved by 25.0% and 31.4%, respectively, and the ratio of swing phase to support phase on the affected side was closer to that of the gait phase on the healthy side, as opposed to the traditional body weight support rehabilitation training model with fixed motion trajectory of pelvic brace. The motion trajectory of the pelvic brace in CoMH mode depends on the current state of the trainer so as to realize the walking training guided by active movement on the healthy side of hemiplegia patients. The strategy of dynamically adjustment of body weight support is more helpful to improve the efficiency of walking rehabilitation training.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Caminhada , Fenômenos Biomecânicos , Marcha , Hemiplegia , Humanos , Pelve , Amplitude de Movimento Articular
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(3): 549-555, 2021 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-34180201

RESUMO

The rotation center of traditional hip disarticulation prosthesis is often placed in the front and lower part of the socket, which is asymmetric with the rotation center of the healthy hip joint, resulting in poor symmetry between the prosthesis movement and the healthy lower limb movement. Besides, most of the prosthesis are passive joints, which need to rely on the amputee's compensatory hip lifting movement to realize the prosthesis movement, and the same walking movement needs to consume 2-3 times of energy compared with normal people. This paper presents a dynamic hip disarticulation prosthesis (HDPs) based on remote center of mechanism (RCM). Using the double parallelogram design method, taking the minimum size of the mechanism as the objective, the genetic algorithm was used to optimize the size, and the rotation center of the prosthesis was symmetrical with the rotation center of the healthy lower limb. By analyzing the relationship between the torque and angle of hip joint in the process of human walking, the control system mirrored the motion parameters of the lower on the healthy side, and used the parallel drive system to provide assistance for the prosthesis. Based on the established virtual prototype simulation platform of solid works and Adams, the motion simulation of hip disarticulation prosthesis was carried out and the change curve was obtained. Through quantitative comparison with healthy lower limb and traditional prosthesis, the scientificity of the design scheme was analyzed. The results show that the design can achieve the desired effect, and the design scheme is feasible.


Assuntos
Artroplastia de Quadril , Membros Artificiais , Prótese de Quadril , Fenômenos Biomecânicos , Articulação do Quadril , Humanos , Desenho de Prótese , Amplitude de Movimento Articular , Caminhada
12.
J Electrocardiol ; 63: 57-63, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33142181

RESUMO

BACKGROUND: Ultra-short-term heart rate variability (HRV) analysis (< 5 min) has been extensively growing in the field of exercise performance for autonomic assessment. However, the validation of ultra-short-term HRV was unclear in the recovery period of exercise. This study aimed to elucidate the agreement between ultra-short-term HRV (0-30 s, 0-1 min, 0-2 min, 0-3 min, 0-4 min) and standard short-term HRV (5 min) and to explore the optimal recording duration under rest and post-exercise conditions. METHODS: 69 participants were recruited to perform physical exercise on a treadmill with an intensity of 6 km/h, 9 km/h and 12 km/h, independently. The standard deviation of RR-interval (SDNN) and root mean square of successive differences of RR-intervals (RMSSD) were calculated by using ultra-short periods and standard period at rest condition (Pre-E) and three post-exercise trials, i.e., Post-E1, Post-E2 and Post-E3, respectively. One-way ANOVA with repeated-measures and Cohen's d statistics were conducted, and Bland-Altman analysis and interclass correlation coefficients (ICC) were used to assess the levels of agreement. RESULTS: For SDNN and RMSSD, the results of agreement analysis at rest condition were different from those at post-exercise. At Pre-E, SDNN and RMSSD were reliable for ultra-short-term HRV analysis at all ultra-short periods, i.e., 0-30 s, 0-1 min, 0-2 min, 0-3 min and 0-4 min, with most ICCs greater than 0.9 and Cohen's d showing trivial differences (Cohen's d = 0.024-0.117). However, at post-exercise, SDNN0-30s, SDNN0-1min, RMSSD0-30s and RMSSD0-1min showed significant differences with SDNN5min and RMSSD5min, respectively (p < 0.01), and the ICCs was not perfect (< 0.9). HRV analysis with time duration longer than 2 min showed nearly perfect reliability in all post-exercise trials, with trivial differences (Cohen's d = -0.003-0.110) and perfect ICCs (ICCs = 0.916-0.998). Furthermore, the limits of the agreement became tighter as the period duration increased in Bland-Altman plots. CONCLUSIONS: This study demonstrated that ultra-short-term HRV analysis was a good surrogate of standard HRV time-domain measures to reflect the autonomic regulation at rest and post-exercise. Specifically, ultra-short-term HRV0-30s or HRV0-1min was recommended at rest condition, whereas longer than 2 min recording period was reliable to obtain SDNN and RMSSD for the accuracy of HRV analysis.


Assuntos
Sistema Nervoso Autônomo , Eletrocardiografia , Teste de Esforço , Frequência Cardíaca , Humanos , Reprodutibilidade dos Testes
13.
Sensors (Basel) ; 20(8)2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32295090

RESUMO

Initial calibration is a great challenge for cuff-less blood pressure (BP) measurement. The traditional one point-to-point (oPTP) calibration procedure only uses one sample/point to obtain unknown parameters of a specific model in a calm state. In fact, parameters such as pulse transit time (PTT) and BP still have slight fluctuations at rest for each subject. The conventional oPTP method had a strong sensitivity in the selection of initial value. Yet, the initial sensitivity of calibration has not been reported and investigated in cuff-less BP motoring. In this study, a mean point-to-point (mPTP) paring calibration method through averaging and balancing calm or peaceful states was proposed for the first time. Thus, based on mPTP, a factor point-to-point (fPTP) paring calibration method through introducing the penalty factor was further proposed to improve and optimize the performance of BP estimation. Using the oPTP, mPTP, and fPTP methods, a total of more than 100,000 heartbeat samples from 21 healthy subjects were tested and validated in the PTT-based BP monitoring technologies. The results showed that the mPTP and fPTP methods significantly improved the performance of estimating BP compared to the conventional oPTP method. Moreover, the mPTP and fPTP methods could be widely popularized and applied, especially the fPTP method, on estimating cuff-less diastolic blood pressure (DBP). To this extent, the fPTP method weakens the initial calibration sensitivity of cuff-less BP estimation and fills in the ambiguity for individualized calibration procedure.


Assuntos
Determinação da Pressão Arterial/métodos , Pressão Sanguínea/fisiologia , Algoritmos , Balistocardiografia , Determinação da Pressão Arterial/instrumentação , Eletrocardiografia , Feminino , Humanos , Masculino , Fotopletismografia , Análise de Onda de Pulso , Adulto Jovem
14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(2): 334-337, 2019 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-31016953

RESUMO

The motor nervous system transmits motion control information through nervous oscillations, which causes the synchronous oscillatory activity of the corresponding muscle to reflect the motion response information and give the cerebral cortex feedback, so that it can sense the state of the limbs. This synchronous oscillatory activity can reflect connectivity information of electroencephalography-electromyography (EEG-EMG) functional coupling. The strength of the coupling is determined by various factors including the strength of muscle contraction, attention, motion intention etc. It is very significant to study motor functional evaluation and control methods to analyze the changes of EEG-EMG synchronous coupling caused by different factors. This article mainly introduces and compares coherence and Granger causality of linear methods, the mutual information and transfer entropy of nonlinear methods in EEG-EMG synchronous coupling, and summarizes the application of each method, so that researchers in related fields can understand the current research progress on analysis methods of EEG-EMG synchronous systematically.


Assuntos
Eletroencefalografia , Eletromiografia , Córtex Motor/fisiologia , Músculo Esquelético/fisiologia , Humanos , Pesquisa
15.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(6): 924-929, 2019 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-31875365

RESUMO

A software and hardware platform for gait simulation and system evaluation for lower limb intelligent prosthesis is proposed and designed, in order that the wearable symmetry effect of the intelligent knee prosthesis can be quantitatively analyzed by machine test instead of human wear test. The whole-body three-dimensional gait and motion analysis system instrument, a device to collect gait data such as joint angle and stride of adults, was used for extracting simulated gait characteristic curve. Then, the gait curve was fitted based on the corresponding joint to verify the feasibility of the test platform in the experiment. Finally, the developed artificial knee prosthesis was worn on the prosthetic evaluation system to quantitatively analyze the gait symmetry effect. The results showed that there was no significant difference in gait symmetry between the developed knee joints at different speeds, which could reach more than 88%. The simulation and evaluation of the prosthetic gait have good effects on the functional simulation and evaluation of the lower limb intelligent prosthesis.


Assuntos
Marcha , Prótese do Joelho , Adulto , Membros Artificiais , Fenômenos Biomecânicos , Humanos , Articulação do Joelho , Desenho de Prótese
16.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(5): 733-739, 2018 10 25.
Artigo em Zh | MEDLINE | ID: mdl-30370712

RESUMO

The performance of intelligent prosthetic knee has an important effect on the realization of physiological gait of transfemoral amputees. A new type of single axis hydraulic damping knee prosthesis was designed based on the analysis of physiological gait. The training methods of the stance and swing phase were proposed. Knee prosthesis test was done through simulation and measurement device. The control target of peak flexion angle during swing of knee prosthesis is chosen to be 60-70°. When the damper valve closure was 0%, maximum swing-phase knee flexion angle of knee prosthesis were (86±2)°, (91±3)° and (97±3)° with the speed of 0.8 m/s, 1.2 m/s and 1.8 m/s, respectively. Once the valve closure was changed, maximum swing-phase knee flexion angle with different speeds could be adjusted between 60° and 70° and the required valve closure percentage were separately 25%, 40% and 70%. The damping adjustment law of intelligent knee prosthesis to achieve physiological gait was revealed.

17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(4): 621-630, 2018 08 25.
Artigo em Zh | MEDLINE | ID: mdl-30124027

RESUMO

Rapid and accurate recognition of human action and road condition is a foundation and precondition of implementing self-control of intelligent prosthesis. In this paper, a Gaussian mixture model and hidden Markov model are used to recognize the road condition and human motion modes based on the inertial sensor in artificial limb (lower limb). Firstly, the inertial sensor is used to collect the acceleration, angle and angular velocity signals in the direction of x , y and z axes of lower limbs. Then we intercept the signal segment with the time window and eliminate the noise by wavelet packet transform, and the fast Fourier transform is used to extract the features of motion. Then the principal component analysis (PCA) is carried out to remove redundant information of the features. Finally, Gaussian mixture model and hidden Markov model are used to identify the human motion modes and road condition. The experimental results show that the recognition rate of routine movement (walking, running, riding, uphill, downhill, up stairs and down stairs) is 96.25%, 92.5%, 96.25%, 91.25%, 93.75%, 88.75% and 90% respectively. Compared with the support vector machine (SVM) method, the results show that the recognition rate of our proposed method is obviously higher, and it can provide a new way for the monitoring and control of the intelligent prosthesis in the future.

18.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(3): 452-459, 2018 06 25.
Artigo em Zh | MEDLINE | ID: mdl-29938955

RESUMO

With the aging of the society, the number of stroke patients has been increasing year by year. Compared with the traditional rehabilitation therapy, the application of upper limb rehabilitation robot has higher efficiency and better rehabilitation effect, and has become an important development direction in the field of rehabilitation. In view of the current development status and the deficiency of upper limb rehabilitation robot system, combined with the development trend of all kinds of products of the upper limb rehabilitation robot, this paper designed a center-driven upper limb rehabilitation training robot for cable transmission which can help the patients complete 6 degrees of freedom (3 are driven, 3 are underactuated) training. Combined the structure of robot with more joints rehabilitation training, the paper choosed a cubic polynomial trajectory planning method in the joint space planning to design two trajectories of eating and lifting arm. According to the trajectory equation, the movement trajectory of each joint of the robot was drawn in MATLAB. It laid a foundation for scientific and effective rehabilitation training. Finally, the experimental prototype is built, and the mechanical structure and design trajectories are verified.


Assuntos
Braço , Robótica , Reabilitação do Acidente Vascular Cerebral , Braço/fisiopatologia , Humanos , Modalidades de Fisioterapia
19.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 33(1): 23-30, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-27382735

RESUMO

Based on the structure and motion bionic principle of the normal adult fingers, biological characteristics of human hands were analyzed, and a wearable exoskeleton hand function training device for the rehabilitation of stroke patients or patients with hand trauma was designed. This device includes the exoskeleton mechanical structure and the electromyography (EMG) control system. With adjustable mechanism, the device was capable to fit different finger lengths, and by capturing the EMG of the users' contralateral limb, the motion state of the exoskeleton hand was controlled. Then driven by the device, the user's fingers conducting adduction/abduction rehabilitation training was carried out. Finally, the mechanical properties and training effect of the exoskeleton hand were verified through mechanism simulation and the experiments on the experimental prototype of the wearable exoskeleton hand function training device.


Assuntos
Exoesqueleto Energizado , Mãos , Reabilitação do Acidente Vascular Cerebral , Biônica/instrumentação , Eletromiografia , Dedos , Humanos , Movimento (Física)
20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 33(6): 1168-75, 2016 Dec.
Artigo em Zh | MEDLINE | ID: mdl-29715415

RESUMO

In order to help the patients with upper-limb disfunction go on rehabilitation training,this paper proposed an upper-limb exoskeleton rehabilitation robot with four degrees of freedom(DOF),and realized two control schemes,i.e.,voice control and electromyography control.The hardware and software design of the voice control system was completed based on RSC-4128 chips,which realized the speech recognition technology of a specific person.Besides,this study adapted self-made surface eletromyogram(sEMG)signal extraction electrodes to collect sEMG signals and realized pattern recognition by conducting sEMG signals processing,extracting time domain features and fixed threshold algorithm.In addition,the pulse-width modulation(PWM)algorithm was used to realize the speed adjustment of the system.Voice control and electromyography control experiments were then carried out,and the results showed that the mean recognition rate of the voice control and electromyography control reached 93.1%and 90.9%,respectively.The results proved the feasibility of the control system.This study is expected to lay a theoretical foundation for the further improvement of the control system of the upper-limb rehabilitation robot.


Assuntos
Exoesqueleto Energizado , Reabilitação , Robótica , Extremidade Superior/fisiopatologia , Algoritmos , Eletrodos , Eletromiografia , Humanos , Processamento de Sinais Assistido por Computador , Software , Fala
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