BACKGROUND The therapeutic role of neurodynamic mobilization in improving lower limb function in patients with mild post-traumatic knee osteoarthritis remains poorly understood.AIM To further elucidate the role of neu...BACKGROUND The therapeutic role of neurodynamic mobilization in improving lower limb function in patients with mild post-traumatic knee osteoarthritis remains poorly understood.AIM To further elucidate the role of neurodynamic mobilization in facilitating knee joint functional recovery.METHODS Thirty-two patients with post-traumatic knee osteoarthritis treated at Chonghua Hospital of Traditional Chinese Medicine(Guilin)from March 2024 to August 2025 were randomly assigned to a control group(n=16)or an intervention group(n=16).Both groups received eight weeks of conventional treatment;and the intervention group additionally underwent neurodynamic mobilization.Outcomes including pain assessed by the visual analogue scale,active range of motion,Lysholm score,stork stand test,single hop test,and Y-balance test were assessed before and after the intervention.RESULTS There were no significant differences between the two groups in baseline characteristics,including gender,age,body mass index,or surgical side(P>0.05).Two-way repeated-measures analysis of variance demonstrated significant time×group interaction effects for the visual analogue scale score(F=13.364,P<0.05),Lysholm knee score(F=20.385,P<0.05),stork stand test(F=103.756,P<0.05),and Y-balance test score(F=8.089,P<0.05).CONCLUSION Neurodynamic mobilization effectively reduces pain,improves knee function,and enhances lower limb balance in patients with mild post-traumatic knee osteoarthritis.展开更多
This research presents a Human Lower Limb Activity Recognition(HLLAR)system that identifies specific activities and predicts the angles of the knees simultaneously,based on the EMG signals.The HLLAR systems streamline...This research presents a Human Lower Limb Activity Recognition(HLLAR)system that identifies specific activities and predicts the angles of the knees simultaneously,based on the EMG signals.The HLLAR systems streamlines the research on the lower limb activities.The HILLAR model includes Discrete Hermite Wavelets Transform-based Synchrosqueezing(DHWTS),Deep Two-Layer Multiscale Convolutional Neural Network(DTLMCNN),and Generalized Regression Neural Network(GRNN)as feature extraction,activity recognition,and knee angle prediction respectively.Electromyography signal-based automatic lower limb activity detection is crucial to rehabilitation and human movement analysis.Yet several of these methods face issues in feature extraction in complex data,overlapping signals,extraction of crucial parameters,and adaptation constraints.This research aims classify lower limb activities and predict knee joint angles from electromy-ography signals using HILLAR model.The model is validated on two datasets,comprising 26 subjects performing three classes of activities:walking,standing,and sitting.The proposed model obtained a classification accuracy of 99.95%,along with significant achievements in precision(99.93%),recall(99.91%),and F1-score(99.93%).The generalized regression neural network predicted angles of the knee joint with a root mean squared error of 1.25%.Robustness is demonstrated through consistent results in five-fold cross-validation and statistical significance testing(p-value=0.004,McNemar's test).Additionally,the proposed model showed superior performance over baseline methods by reducing error rates by 18%and decreasing processing time to 0.98 s.展开更多
The development of brain-computer interfaces(BCI)based on motor imagery(MI)has greatly improved patients’quality of life with movement disorders.The classification of upper limb MI has been widely studied and applied...The development of brain-computer interfaces(BCI)based on motor imagery(MI)has greatly improved patients’quality of life with movement disorders.The classification of upper limb MI has been widely studied and applied in many fields,including rehabilitation.However,the physiological representations of left and right lower limb movements are too close and activated deep in the cerebral cortex,making it difficult to distinguish their features.Therefore,classifying lower limbs motor imagery is more challenging.In this study,we propose a feature extraction method based on functional connectivity,which utilizes phase-locked values to construct a functional connectivity matrix as the features of the left and right legs,which can effectively avoid the problem of physiological representations of the left and right lower limbs being too close to each other during movement.In addition,considering the topology and the temporal characteristics of the electroencephalogram(EEG),we designed a temporal-spatial convolutional network(TSGCN)to capture the spatiotemporal information for classification.Experimental results show that the accuracy of the proposed method is higher than that of existing methods,achieving an average classification accuracy of 73.58%on the internal dataset.Finally,this study explains the network mechanism of left and right foot MI from the perspective of graph theoretic features and demonstrates the feasibility of decoding lower limb MI.展开更多
Background Frailty is a major determinant of outcomes in patients with coronary artery disease(CAD)undergoing lower limb amputation.This study evaluates the impact of frailty on in-hospital outcomes in these patients....Background Frailty is a major determinant of outcomes in patients with coronary artery disease(CAD)undergoing lower limb amputation.This study evaluates the impact of frailty on in-hospital outcomes in these patients.Methods We performed a retrospective analysis of the National Inpatient Sample(2016–2021)to identify adult patients with CAD who underwent lower limb amputation.Frailty was defined using the Johns Hopkins Adjusted Clinical Groups(ACG)frailty indicator.Multivariable logistic regression was used to assess the independent association of frailty with in-hospital outcomes,and propensity score matching(PSM)was performed to further account for confounding factors.Results After PSM,9,990 patients were included in each cohort.Frail patients experienced higher rates of in-hospital mortality(3.9%vs.1.5%,P<0.001),acute limb ischemia(3.8%vs.3.1%,P=0.015),fasciotomy(2.1%vs.1.4%,P<0.001),stump infection(7.9%vs.6.6%,P<0.001),cardiogenic shock(0.9%vs.0.7%,P=0.032),sudden cardiac arrest(2.7%vs.2.1%,P=0.004),mechanical circulatory support(0.3%vs.0.2%,P=0.028),major adverse cardiac and cerebrovascular events(7.7%vs.5.4%,P<0.001),and sepsis(18.3%vs.13.8%,P<0.001).In multivariable logistic regression analysis,frailty remained an independent predictor of inhospital mortality and major complications.Conclusion Frailty is independently associated with increased in-hospital mortality and adverse events among CAD patients undergoing lower limb amputation.Incorporating frailty assessment into preoperative evaluation may improve risk stratification and guide clinical decision-making in this high-risk population.展开更多
Purpose: To evaluate open lower limb trauma management in children. Me-thod: We conducted a twelve-month cross-sectional prospective study. Results: Open trauma of lower limb had 7.9% of hospital frequency. Mean age w...Purpose: To evaluate open lower limb trauma management in children. Me-thod: We conducted a twelve-month cross-sectional prospective study. Results: Open trauma of lower limb had 7.9% of hospital frequency. Mean age was 8 years with a sex ratio of 2.45. In 68.4% of cases, trauma occurred in road traffic accidents. Average consultation time was 2.4 hours. Trauma mainly affected the leg in 39.5% of cases, and the thigh in 34.2%. Soft tissue wounds occurred in 52.6% of cases, and open fractures in 47.4%. Average response time was one hour. Wound trimming and suturing were performed in 76.3% of cases and combined with bone nailing in 15.8%. The outcome was favorable in 92.1% of cases. Average hospital stay was 4.37 days. Conclusion: Open trauma to the lower limb is a frequent and occurs mainly in road traffic accidents. Management was early, with a favorable outcome for most patients and a short hospital stay.展开更多
Objective:To evaluate the effect of task-oriented training combined with a lower limb rehabilitation robot on improving motor function and ankle joint function in stroke patients with hemiplegia.Methods:Sixty-three st...Objective:To evaluate the effect of task-oriented training combined with a lower limb rehabilitation robot on improving motor function and ankle joint function in stroke patients with hemiplegia.Methods:Sixty-three stroke patients with hemiplegia admitted to our hospital from January 2022 to June 2024 were randomly divided into observation group(32 cases)and control group(31 cases)using the envelope method.The control group received task-oriented training,while the observation group received additional lower limb rehabilitation robot training.The motor function(Fugl-Meyer Assessment of Lower Extremity,FMA-LE)and ankle joint function(Active Dorsiflexion Range of Motion,DF AROM)were compared between the two groups.Results:After treatment,the levels of FMA-LE and DF AROM in both groups increased significantly,and the improvement in each index in the observation group was better than that in the control group(P<0.05).Conclusion:The combination of task-oriented training and lower limb rehabilitation robot training can more effectively improve the overall motor function of the lower limbs and the active dorsiflexion ability of the ankle joint in stroke patients with hemiplegia.展开更多
Varicose veins of the lower limbs are a cosmopolitan condition, thought to be rare in Africa but widespread in Europe. The aim of this study is to analyze the indications and evaluate the results of surgical managemen...Varicose veins of the lower limbs are a cosmopolitan condition, thought to be rare in Africa but widespread in Europe. The aim of this study is to analyze the indications and evaluate the results of surgical management of varicose pathology of the IM in Dakar. We enrolled 280 patients, with a mean age of 36 and a sex ratio of 2. Factors favouring venous disease were dominated by prolonged orthostatism and multiparity. The average consultation time was 6 years. The reasons for consultation were functional manifestations, progressive complications and aesthetics. The venous trunks concerned were the great saphenous vein (GSV) in 58.9% of cases, the small saphenous vein (SSV) in 29% of cases, perforating veins and varicose veins were unsystematized in 28.5% of cases. Surgery was performed under spinal anaesthesia. Surgical procedures were dominated by stripping of the GSV, crossectomy of the SSV and staged ligations. One patient developed meningismus immediately after the operation. Average follow-up was 2 years. Mortality was null.展开更多
[Objectives]To explore the effectiveness of exercise therapy for lower limb lymphedema after cervical cancer surgery,and to inform future research and clinical practice in developing evidence-based nursing interventio...[Objectives]To explore the effectiveness of exercise therapy for lower limb lymphedema after cervical cancer surgery,and to inform future research and clinical practice in developing evidence-based nursing interventions.[Methods]Using the JBI scoping review guidelines as a methodological framework,relevant studies were retrieved from PubMed,Embase,Web of Science,Cochrane Library,CINAHL,CNKI,Wanfang Data,and Chinese Biomedical Literature Database from their inception to December 2024.[Results]The findings of included 18 studies showed that exercise therapy,mainly including progressive resistance training,aerobic exercise,aquatic exercise,and mixed exercise modalities,could effectively alleviate lower limb lymphedema symptoms in patients after cervical cancer surgery and improve quality of life.Progressive resistance training has been proven to be a safe and feasible preventive intervention;aerobic exercise and aquatic exercise have certain relieving effects on established lymphedema;mixed exercise interventions can improve patients functional activity capacity.[Conclusions]Exercise therapy is a feasible,safe,and effective intervention for lower limb lymphedema after cervical cancer surgery.Future high-quality randomized controlled trials are required to validate the effectiveness of different exercise modalities and to develop individualized exercise prescriptions that enhance patient adherence and reduce complications.展开更多
To overcome the limitations of traditional exoskeletons in complex outdoor terrains,this study introduces a novel lower limb exoskeleton inspired by the snow leopard’s forelimb musculoskeletal structure.It features a...To overcome the limitations of traditional exoskeletons in complex outdoor terrains,this study introduces a novel lower limb exoskeleton inspired by the snow leopard’s forelimb musculoskeletal structure.It features a non-fully anthropomorphic design,attaching only at the thigh and ankle with a backward-knee configuration to mimic natural human knee movement.The design incorporates a single elastic element at the hip for gravity compensation and dual elastic elements at the knee for terrain adaptability,which adjust based on walking context.The design’s effectiveness was assessed by measuring metabolic cost reduction and motor output torque under various walking conditions.Results showed significant metabolic cost savings of 5.8–8.8%across different speeds and a 7.9%reduction during 9°incline walking on a flat indoor surface.Additionally,the spring element decreased hip motor output torque by 7–15.9%and knee torque by 8.1–14.2%.Outdoor tests confirmed the design’s robustness and effectiveness in reducing motor torque across terrains,highlighting its potential to advance multi-terrain adaptive exoskeleton research.展开更多
The lower limb assisted exoskeleton is a prominent area of research within the field of exoskeleton technology.However,several challenges remain,including the development of flexible actuators,high battery consumption...The lower limb assisted exoskeleton is a prominent area of research within the field of exoskeleton technology.However,several challenges remain,including the development of flexible actuators,high battery consumption,the risk of joint misalignment,and limited assistive capabilities.This paper proposes a compact flexible actuator incorporating two elastic elements named Adjustable Energy Storage Series Elastic Actuator(AES-SEA),which combining an adjustable energy storage device with a series elastic actuator for application in exoskeleton hip joints.This design aims to enhance energy efficiency and improve assistive effects.Subsequently,we introduce a novel knee joint bionic structure based on a pulley-groove configuration and a four-link mechanism,designed to replicate human knee joint motion and prevent joint misalignment.Additionally,we propose an innovative controller that integrates concepts from Linear Quadratic Regulator(LQR)control and virtual tunnel for level walking assistance.This controller modulates the assisted reference trajectory using the virtual tunnel concept,enabling different levels of assistance both inside and outside the tunnel by adjusting the parameters Q and R.This approach enhances the assisting force while ensuring the safety of human-computer interaction.Finally,metabolic experiments were conducted to evaluate the effectiveness of the exoskeleton assistance.展开更多
BACKGROUND Serum retinol-binding protein(RBP)is the primary transport protein of circulating vitamin A.RBP has a crucial role in maintaining nutrient metabolism and physiologic homeostasis.Several studies have indicat...BACKGROUND Serum retinol-binding protein(RBP)is the primary transport protein of circulating vitamin A.RBP has a crucial role in maintaining nutrient metabolism and physiologic homeostasis.Several studies have indicated that serum RBP participates in the progression of diabetes and diabetes-related complications.However,the impact of serum RBP on lower limb atherosclerosis has not been determined in individuals with type 2 diabetes mellitus(T2DM).AIM To determine the association between serum RBP and lower limb atherosclerosis in individuals with T2DM.METHODS This retrospective study enrolled 4428 eligible T2DM patients and divided the patients into non-lower limb atherosclerosis(n=1913)and lower limb atherosclerosis groups(n=2515)based on lower limb arterial ultrasonography results.At hospital admission,baseline serum RBP levels were assessed,and all subjects were categorized into three groups(Q1-Q3)based on RBP tertiles.Logistic regression,restricted cubic spline regression,subgroup analysis,and machine learning were used to assess the association between RBP levels and lower limb atherosclerosis risk.RESULTS Among 4428 individuals with T2DM,2515(56.80%)had lower limb atherosclerosis.Logistic analysis showed that lower limb atherosclerosis risk increased by 1%for every 1 unit rise in serum RBP level(odds ratio=1.01,95%confidence interval:1.00-1.02,P=0.004).Patients in the highest tertile group(Q3)had a higher lower limb atherosclerosis risk compared to the lowest tertile group(Q1)(odds ratio=1.36,95%confidence interval:1.12-1.67,P=0.002).The lower limb atherosclerosis risk gradually increased with an increase in RBP tertile(P for trend=0.005).Restricted cubic spline analysis indicated a linear correlation between serum RBP levels and lower limb atherosclerosis risk(non-linear P<0.05).Machine learning demonstrated the significance and diagnostic value of serum RBP in predicting lower limb atherosclerosis risk.CONCLUSION Elevated serum RBP levels correlate with an increased lower limb atherosclerosis risk in individuals with T2DM.展开更多
BACKGROUND In 2017,our institution implemented a high efficiency(HE)pathway for lower limb orthopedic surgery.The employed strategy included patient selection,surgical instrument standardization,preoperative surgical ...BACKGROUND In 2017,our institution implemented a high efficiency(HE)pathway for lower limb orthopedic surgery.The employed strategy included patient selection,surgical instrument standardization,preoperative surgical nerve blocks,avoidance of general anesthesia and bypassing phase one recovery.We conducted a historic cohort study whose primary outcome was the postoperative recovery time between the HE and traditional(T)pathway.AIM To determine whether the implementation of a HE pathway was correlated with a reduction in postoperative recovery time.METHODS Patients who had unilateral elective lower limb orthopedic procedures through the T and HE pathway were screened between 2017 to 2019.Patients were at least 18 years old,and American Society of Anesthesiologists(ASA)Physical Status I to III without major systemic comorbidities were included.Propensity score was generated using multivariable regression taking age,body mass index,sex,ASA class and surgical type as covariates using nearest neighbour methods between the two pathways.Mann Whitney U test were used to analyzed total postoperative time.RESULTS There was an associated reduction in total postoperative recovery time of 63 minutes(95%CI:-69 to-57)in the HE group.The operating room time and total length of stay also had an associated decrease of 20 minutes(95%CI:-23 to-17)and 84 minutes(95%CI:-92 to-75)respectively.CONCLUSION Utilizing multifaceted strategies to improve perioperative efficiency was associated with a reduction in the postoperative recovery time in our retrospective study.This model can be a potential strategy to deal with surgical backlog in the face of ongoing human resource challenges.展开更多
BACKGROUND Lower limb atherosclerotic occlusive disease(LAOD)is a common complication in diabetic patients,leading to significant symptoms and reduced quality of life.AIM To investigate the efficacy of autologous plat...BACKGROUND Lower limb atherosclerotic occlusive disease(LAOD)is a common complication in diabetic patients,leading to significant symptoms and reduced quality of life.AIM To investigate the efficacy of autologous platelet-rich gel(APRG)as an innovative treatment for LAOD,focusing on clinical outcomes such as symptom relief,flow values,ankle-brachial index(ABI),walking distance,and claudication severity.METHODS This retrospective study involved an analysis of electronic medical records(EMR)from 150 patients diagnosed with LAOD.Participants were assigned to either a treatment group(n=80)or a control group(n=70).Both groups received standard care and underwent dressing changes.In addition,the treatment group was given APRG.Primary outcomes included changes in pain levels,wound healing rates,flow values assessed by plethysmography,ABI measurements,walking distance,and claudication severity.Statistical analyses were conducted to determine the significance of the results.RESULTS The APRG group showed significant improvements after 12 weeks,including a 70%reduction in pain,a 65%increase in wound healing rates,and an average walking distance increase of 150 meters.Flow values improved by 20%,with significant enhancements in ABI measurements(P<0.01).Additionally,patient satisfaction was higher,and 60%of patients reported improved claudication severity,confirming the efficacy of APRG in enhancing clinical outcomes for lower LAOD.CONCLUSION The APRG demonstrates significant efficacy in managing LAOD in diabetic patients,improving key clinical parameters including flow values,ABI,walking distance,and claudication.These findings support the need for further prospective studies to validate long-term efficacy and optimize treatment strategies.展开更多
As an essential tool for quantitative analysis of lower limb coordination,optical motion capture systems with marker-based encoding still suffer from inefficiency,high costs,spatial constraints,and the requirement for...As an essential tool for quantitative analysis of lower limb coordination,optical motion capture systems with marker-based encoding still suffer from inefficiency,high costs,spatial constraints,and the requirement for multiple markers.While 3D pose estimation algorithms combined with ordinary cameras offer an alternative,their accuracy often deteriorates under significant body occlusion.To address the challenge of insufficient 3D pose estimation precision in occluded scenarios—which hinders the quantitative analysis of athletes’lower-limb coordination—this paper proposes a multimodal training framework integrating spatiotemporal dependency networks with text-semantic guidance.Compared to traditional optical motion capture systems,this work achieves low-cost,high-precision motion parameter acquisition through the following innovations:(1)spatiotemporal dependency attention module is designed to establish dynamic spatiotemporal correlation graphs via cross-frame joint semantic matching,effectively resolving the feature fragmentation issue in existing methods.(2)noise-suppressed multi-scale temporal module is proposed,leveraging KL divergence-based information gain analysis for progressive feature filtering in long-range dependencies,reducing errors by 1.91 mm compared to conventional temporal convolutions.(3)text-pose contrastive learning paradigm is introduced for the first time,where BERT-generated action descriptions align semantic-geometric features via the BERT encoder,significantly enhancing robustness under severe occlusion(50%joint invisibility).On the Human3.6M dataset,the proposed method achieves an MPJPE of 56.21 mm under Protocol 1,outperforming the state-of-the-art baseline MHFormer by 3.3%.Extensive ablation studies on Human3.6M demonstrate the individual contributions of the core modules:the spatiotemporal dependency module and noise-suppressed multi-scale temporal module reduce MPJPE by 0.30 and 0.34 mm,respectively,while the multimodal training strategy further decreases MPJPE by 0.6 mm through text-skeleton contrastive learning.Comparative experiments involving 16 athletes show that the sagittal plane coupling angle measurements of hip-ankle joints differ by less than 1.2°from those obtained via traditional optical systems(two one-sided t-tests,p<0.05),validating real-world reliability.This study provides an AI-powered analytical solution for competitive sports training,serving as a viable alternative to specialized equipment.展开更多
Focusing on the rehabilitation training of hemiplegia patients,this paper proposes a gait-planning strategy based on a central pattern generator and an adaptive time-delay control scheme that utilizes recursive termin...Focusing on the rehabilitation training of hemiplegia patients,this paper proposes a gait-planning strategy based on a central pattern generator and an adaptive time-delay control scheme that utilizes recursive terminal sliding mode for lower limb rehabilitation exoskeleton robots.The central pattern generator network plans a reference gait trajectory for the affected leg,synchronized with the movement of the healthy leg.The proposed adaptive time-delay control scheme possesses a model-independent property due to the mechanism of time-delay estimation,with adaptive control gains that enhance the resilience against system perturbations and a recursive terminal sliding mode control component to achieve a fast convergence rate.According to the Lyapunov stability criterion,it is proved that the gait trajectory-tracking error is uniformly ultimately bounded.Experiments are conducted on a lower limb exoskeleton experimental platform,and the experimental results demonstrate the effectiveness and superiority of the proposed strategies.展开更多
Rehabilitation of lower limb amputation in developing countries is quite challenging.Though there are basic to highly advanced prostheses available in India,the set-up is still facing difficulties in developing countr...Rehabilitation of lower limb amputation in developing countries is quite challenging.Though there are basic to highly advanced prostheses available in India,the set-up is still facing difficulties in developing countries.Prosthetic management is difficult due to lack of availability of prostheses and reduced affordability among low income populations.In this review we highlighted the lower limb amputation and prosthetic rehabilitation status in India.Currently,India is advancing well in the rehabilitation field,but further studies are required to provide more evidence and recommendation.展开更多
Due to the close physical interaction between human and machine in process of gait training, lower limb exoskeletons should be safe, comfortable and able to smoothly transfer desired driving force/moments to the patie...Due to the close physical interaction between human and machine in process of gait training, lower limb exoskeletons should be safe, comfortable and able to smoothly transfer desired driving force/moments to the patients. Correlatively, in kinematics the exoskeletons are required to be compatible with human lower limbs and thereby to avoid the uncontrollable interactional loads at the human-machine interfaces. Such requirement makes the structure design of exoskeletons very difficult because the human-machine closed chains are complicated. In addition, both the axis misalignments and the kinematic character difference between the exoskeleton and human joints should be taken into account. By analyzing the DOF（degree of freedom） of the whole human-machine closed chain, the human-machine kinematic incompatibility of lower limb exoskeletons is studied. An effective method for the structure design of lower limb exoskeletons, which are kinematically compatible with human lower limb, is proposed. Applying this method, the structure synthesis of the lower limb exoskeletons containing only one-DOF revolute and prismatic joints is investigated; the feasible basic structures of exoskeletons are developed and classified into three different categories. With the consideration of quasi-anthropopathic feature, structural simplicity and wearable comfort of lower limb exoskeletons, a joint replacement and structure comparison based approach to select the ideal structures of lower limb exoskeletons is proposed, by which three optimal exoskeleton structures are obtained. This paper indicates that the human-machine closed chain formed by the exoskeleton and human lower limb should be an even-constrained kinematic system in order to avoid the uncontrollable human-machine interactional loads. The presented method for the structure design of lower limb exoskeletons is universal and simple, and hence can be applied to other kinds of wearable exoskeletons.展开更多
This paper describes a novel gait pattern recognition method based on Long Short-Term Memory(LSTM)and Convolutional Neural Network(CNN)for lower limb exoskeleton.The Inertial Measurement Unit(IMU)installed on the exos...This paper describes a novel gait pattern recognition method based on Long Short-Term Memory(LSTM)and Convolutional Neural Network(CNN)for lower limb exoskeleton.The Inertial Measurement Unit(IMU)installed on the exoskeleton to collect motion information,which is used for LSTM-CNN input.This article considers five common gait patterns,including walking,going up stairs,going down stairs,sitting down,and standing up.In the LSTM-CNN model,the LSTM layer is used to process temporal sequences and the CNN layer is used to extract features.To optimize the deep neural network structure proposed in this paper,some hyperparameter selection experiments were carried out.In addition,to verify the superiority of the proposed recognition method,the method is compared with several common methods such as LSTM,CNN and SVM.The results show that the average recognition accuracy can reach 97.78%,which has a good recognition eff ect.Finally,according to the experimental results of gait pattern switching,the proposed method can identify the switching gait pattern in time,which shows that it has good real-time performance.展开更多
In this study,a humanoid prototype of 2-DOF(degrees of freedom)lower limb exoskeleton is introduced to evaluate the wearable comfortable effect between person and exoskeleton.To improve the detection accuracy of the h...In this study,a humanoid prototype of 2-DOF(degrees of freedom)lower limb exoskeleton is introduced to evaluate the wearable comfortable effect between person and exoskeleton.To improve the detection accuracy of the humanrobot interaction torque,a BPNN(backpropagation neural networks)is proposed to estimate this interaction force and to compensate for the measurement error of the 3D-force/torque sensor.Meanwhile,the backstepping controller is designed to realize the exoskeleton's passive position control,which means that the person passively adapts to the exoskeleton.On the other hand,a variable admittance controller is used to implement the exoskeleton's active followup control,which means that the person's motion is motivated by his/her intention and the exoskeleton control tries best to improve the human-robot wearable comfortable performance.To improve the wearable comfortable effect,serval regular gait tasks with different admittance parameters and step frequencies are statistically performed to obtain the optimal admittance control parameters.Finally,the BPNN compensation algorithm and two controllers are verified by the experimental exoskeleton prototype with human-robot cooperative motion.展开更多
A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometric differences of the people from different countries,the...A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometric differences of the people from different countries,the present study aims to establish and validate a finite element lower limb model representing 50th Chinese male size for pedestrian safety research,then compare its biomechanical responses with the general models currently in wide use in the world for pedestrian safety evaluation.Concerning the vehicle-pedestrian impact loading environment,the previously developed lower limb model with three-dimensional muscles was adjusted and validated through the related experiments.Then,the biomechanical responses of the validated model were compared with the Total Human Model for Safety(THUMS)and Advanced Pedestrian Legform Impactor(aPLI)models by combing with four typical vehicles.The results showed that both consistency and significant differences of biomechanical responses existed between the present model and the other two models.The injury measurements of the thigh region of the present model showed extremely large differences with the other two models,while the tibia and Medial Collateral Ligament(MCL)injury measurements show similar values.Thus,it can be concluded that directly using the aPLI or THUMS models for Chinese pedestrian safety evaluation is not robust concerning both kinematic responses and injury measurements.展开更多
基金Supported by the Central Guided Local Science and Technology Development Fund Project for Science and Technology Innovation Base Construction,No.Guike ZY24212046National Natural Science Foundation of China,No.U22A2092+3 种基金Guangxi Education Science“the 14th Five-Year Plan”2024 Special Project“Research on Steam Education Practice in Rehabilitation Engineering”,No.2024ZJY304the Research Basic Ability Enhancement Program for Young and Middle-aged Teachers of Guangxi,No.2025KY2255the Innovation Project of GUET Graduate Education,No.2025YCXB010Natural Science Research Project of Guilin Life and Health Career Technical College,No.2025GKKY04.
文摘BACKGROUND The therapeutic role of neurodynamic mobilization in improving lower limb function in patients with mild post-traumatic knee osteoarthritis remains poorly understood.AIM To further elucidate the role of neurodynamic mobilization in facilitating knee joint functional recovery.METHODS Thirty-two patients with post-traumatic knee osteoarthritis treated at Chonghua Hospital of Traditional Chinese Medicine(Guilin)from March 2024 to August 2025 were randomly assigned to a control group(n=16)or an intervention group(n=16).Both groups received eight weeks of conventional treatment;and the intervention group additionally underwent neurodynamic mobilization.Outcomes including pain assessed by the visual analogue scale,active range of motion,Lysholm score,stork stand test,single hop test,and Y-balance test were assessed before and after the intervention.RESULTS There were no significant differences between the two groups in baseline characteristics,including gender,age,body mass index,or surgical side(P>0.05).Two-way repeated-measures analysis of variance demonstrated significant time×group interaction effects for the visual analogue scale score(F=13.364,P<0.05),Lysholm knee score(F=20.385,P<0.05),stork stand test(F=103.756,P<0.05),and Y-balance test score(F=8.089,P<0.05).CONCLUSION Neurodynamic mobilization effectively reduces pain,improves knee function,and enhances lower limb balance in patients with mild post-traumatic knee osteoarthritis.
文摘This research presents a Human Lower Limb Activity Recognition(HLLAR)system that identifies specific activities and predicts the angles of the knees simultaneously,based on the EMG signals.The HLLAR systems streamlines the research on the lower limb activities.The HILLAR model includes Discrete Hermite Wavelets Transform-based Synchrosqueezing(DHWTS),Deep Two-Layer Multiscale Convolutional Neural Network(DTLMCNN),and Generalized Regression Neural Network(GRNN)as feature extraction,activity recognition,and knee angle prediction respectively.Electromyography signal-based automatic lower limb activity detection is crucial to rehabilitation and human movement analysis.Yet several of these methods face issues in feature extraction in complex data,overlapping signals,extraction of crucial parameters,and adaptation constraints.This research aims classify lower limb activities and predict knee joint angles from electromy-ography signals using HILLAR model.The model is validated on two datasets,comprising 26 subjects performing three classes of activities:walking,standing,and sitting.The proposed model obtained a classification accuracy of 99.95%,along with significant achievements in precision(99.93%),recall(99.91%),and F1-score(99.93%).The generalized regression neural network predicted angles of the knee joint with a root mean squared error of 1.25%.Robustness is demonstrated through consistent results in five-fold cross-validation and statistical significance testing(p-value=0.004,McNemar's test).Additionally,the proposed model showed superior performance over baseline methods by reducing error rates by 18%and decreasing processing time to 0.98 s.
基金supported in part by the National Natural Science Foundation of China under Grant 62172368the Natural Science Foundation of Zhejiang Province under Grant LR22F020003.
文摘The development of brain-computer interfaces(BCI)based on motor imagery(MI)has greatly improved patients’quality of life with movement disorders.The classification of upper limb MI has been widely studied and applied in many fields,including rehabilitation.However,the physiological representations of left and right lower limb movements are too close and activated deep in the cerebral cortex,making it difficult to distinguish their features.Therefore,classifying lower limbs motor imagery is more challenging.In this study,we propose a feature extraction method based on functional connectivity,which utilizes phase-locked values to construct a functional connectivity matrix as the features of the left and right legs,which can effectively avoid the problem of physiological representations of the left and right lower limbs being too close to each other during movement.In addition,considering the topology and the temporal characteristics of the electroencephalogram(EEG),we designed a temporal-spatial convolutional network(TSGCN)to capture the spatiotemporal information for classification.Experimental results show that the accuracy of the proposed method is higher than that of existing methods,achieving an average classification accuracy of 73.58%on the internal dataset.Finally,this study explains the network mechanism of left and right foot MI from the perspective of graph theoretic features and demonstrates the feasibility of decoding lower limb MI.
文摘Background Frailty is a major determinant of outcomes in patients with coronary artery disease(CAD)undergoing lower limb amputation.This study evaluates the impact of frailty on in-hospital outcomes in these patients.Methods We performed a retrospective analysis of the National Inpatient Sample(2016–2021)to identify adult patients with CAD who underwent lower limb amputation.Frailty was defined using the Johns Hopkins Adjusted Clinical Groups(ACG)frailty indicator.Multivariable logistic regression was used to assess the independent association of frailty with in-hospital outcomes,and propensity score matching(PSM)was performed to further account for confounding factors.Results After PSM,9,990 patients were included in each cohort.Frail patients experienced higher rates of in-hospital mortality(3.9%vs.1.5%,P<0.001),acute limb ischemia(3.8%vs.3.1%,P=0.015),fasciotomy(2.1%vs.1.4%,P<0.001),stump infection(7.9%vs.6.6%,P<0.001),cardiogenic shock(0.9%vs.0.7%,P=0.032),sudden cardiac arrest(2.7%vs.2.1%,P=0.004),mechanical circulatory support(0.3%vs.0.2%,P=0.028),major adverse cardiac and cerebrovascular events(7.7%vs.5.4%,P<0.001),and sepsis(18.3%vs.13.8%,P<0.001).In multivariable logistic regression analysis,frailty remained an independent predictor of inhospital mortality and major complications.Conclusion Frailty is independently associated with increased in-hospital mortality and adverse events among CAD patients undergoing lower limb amputation.Incorporating frailty assessment into preoperative evaluation may improve risk stratification and guide clinical decision-making in this high-risk population.
文摘Purpose: To evaluate open lower limb trauma management in children. Me-thod: We conducted a twelve-month cross-sectional prospective study. Results: Open trauma of lower limb had 7.9% of hospital frequency. Mean age was 8 years with a sex ratio of 2.45. In 68.4% of cases, trauma occurred in road traffic accidents. Average consultation time was 2.4 hours. Trauma mainly affected the leg in 39.5% of cases, and the thigh in 34.2%. Soft tissue wounds occurred in 52.6% of cases, and open fractures in 47.4%. Average response time was one hour. Wound trimming and suturing were performed in 76.3% of cases and combined with bone nailing in 15.8%. The outcome was favorable in 92.1% of cases. Average hospital stay was 4.37 days. Conclusion: Open trauma to the lower limb is a frequent and occurs mainly in road traffic accidents. Management was early, with a favorable outcome for most patients and a short hospital stay.
文摘Objective:To evaluate the effect of task-oriented training combined with a lower limb rehabilitation robot on improving motor function and ankle joint function in stroke patients with hemiplegia.Methods:Sixty-three stroke patients with hemiplegia admitted to our hospital from January 2022 to June 2024 were randomly divided into observation group(32 cases)and control group(31 cases)using the envelope method.The control group received task-oriented training,while the observation group received additional lower limb rehabilitation robot training.The motor function(Fugl-Meyer Assessment of Lower Extremity,FMA-LE)and ankle joint function(Active Dorsiflexion Range of Motion,DF AROM)were compared between the two groups.Results:After treatment,the levels of FMA-LE and DF AROM in both groups increased significantly,and the improvement in each index in the observation group was better than that in the control group(P<0.05).Conclusion:The combination of task-oriented training and lower limb rehabilitation robot training can more effectively improve the overall motor function of the lower limbs and the active dorsiflexion ability of the ankle joint in stroke patients with hemiplegia.
文摘Varicose veins of the lower limbs are a cosmopolitan condition, thought to be rare in Africa but widespread in Europe. The aim of this study is to analyze the indications and evaluate the results of surgical management of varicose pathology of the IM in Dakar. We enrolled 280 patients, with a mean age of 36 and a sex ratio of 2. Factors favouring venous disease were dominated by prolonged orthostatism and multiparity. The average consultation time was 6 years. The reasons for consultation were functional manifestations, progressive complications and aesthetics. The venous trunks concerned were the great saphenous vein (GSV) in 58.9% of cases, the small saphenous vein (SSV) in 29% of cases, perforating veins and varicose veins were unsystematized in 28.5% of cases. Surgery was performed under spinal anaesthesia. Surgical procedures were dominated by stripping of the GSV, crossectomy of the SSV and staged ligations. One patient developed meningismus immediately after the operation. Average follow-up was 2 years. Mortality was null.
文摘[Objectives]To explore the effectiveness of exercise therapy for lower limb lymphedema after cervical cancer surgery,and to inform future research and clinical practice in developing evidence-based nursing interventions.[Methods]Using the JBI scoping review guidelines as a methodological framework,relevant studies were retrieved from PubMed,Embase,Web of Science,Cochrane Library,CINAHL,CNKI,Wanfang Data,and Chinese Biomedical Literature Database from their inception to December 2024.[Results]The findings of included 18 studies showed that exercise therapy,mainly including progressive resistance training,aerobic exercise,aquatic exercise,and mixed exercise modalities,could effectively alleviate lower limb lymphedema symptoms in patients after cervical cancer surgery and improve quality of life.Progressive resistance training has been proven to be a safe and feasible preventive intervention;aerobic exercise and aquatic exercise have certain relieving effects on established lymphedema;mixed exercise interventions can improve patients functional activity capacity.[Conclusions]Exercise therapy is a feasible,safe,and effective intervention for lower limb lymphedema after cervical cancer surgery.Future high-quality randomized controlled trials are required to validate the effectiveness of different exercise modalities and to develop individualized exercise prescriptions that enhance patient adherence and reduce complications.
基金sponsored by the Fundamental Research Funds for the Central Universities[N2329001].
文摘To overcome the limitations of traditional exoskeletons in complex outdoor terrains,this study introduces a novel lower limb exoskeleton inspired by the snow leopard’s forelimb musculoskeletal structure.It features a non-fully anthropomorphic design,attaching only at the thigh and ankle with a backward-knee configuration to mimic natural human knee movement.The design incorporates a single elastic element at the hip for gravity compensation and dual elastic elements at the knee for terrain adaptability,which adjust based on walking context.The design’s effectiveness was assessed by measuring metabolic cost reduction and motor output torque under various walking conditions.Results showed significant metabolic cost savings of 5.8–8.8%across different speeds and a 7.9%reduction during 9°incline walking on a flat indoor surface.Additionally,the spring element decreased hip motor output torque by 7–15.9%and knee torque by 8.1–14.2%.Outdoor tests confirmed the design’s robustness and effectiveness in reducing motor torque across terrains,highlighting its potential to advance multi-terrain adaptive exoskeleton research.
基金supported by Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology(MISIMT-2021-4)the Fundamental Research Funds for the Central Universities(N2329001).
文摘The lower limb assisted exoskeleton is a prominent area of research within the field of exoskeleton technology.However,several challenges remain,including the development of flexible actuators,high battery consumption,the risk of joint misalignment,and limited assistive capabilities.This paper proposes a compact flexible actuator incorporating two elastic elements named Adjustable Energy Storage Series Elastic Actuator(AES-SEA),which combining an adjustable energy storage device with a series elastic actuator for application in exoskeleton hip joints.This design aims to enhance energy efficiency and improve assistive effects.Subsequently,we introduce a novel knee joint bionic structure based on a pulley-groove configuration and a four-link mechanism,designed to replicate human knee joint motion and prevent joint misalignment.Additionally,we propose an innovative controller that integrates concepts from Linear Quadratic Regulator(LQR)control and virtual tunnel for level walking assistance.This controller modulates the assisted reference trajectory using the virtual tunnel concept,enabling different levels of assistance both inside and outside the tunnel by adjusting the parameters Q and R.This approach enhances the assisting force while ensuring the safety of human-computer interaction.Finally,metabolic experiments were conducted to evaluate the effectiveness of the exoskeleton assistance.
基金The study was approved by the ethics committee of Southwest Hospital,the First Affiliated Hospital of Army Medical University of Chinese People's Liberation Army(No.KY2024007).
文摘BACKGROUND Serum retinol-binding protein(RBP)is the primary transport protein of circulating vitamin A.RBP has a crucial role in maintaining nutrient metabolism and physiologic homeostasis.Several studies have indicated that serum RBP participates in the progression of diabetes and diabetes-related complications.However,the impact of serum RBP on lower limb atherosclerosis has not been determined in individuals with type 2 diabetes mellitus(T2DM).AIM To determine the association between serum RBP and lower limb atherosclerosis in individuals with T2DM.METHODS This retrospective study enrolled 4428 eligible T2DM patients and divided the patients into non-lower limb atherosclerosis(n=1913)and lower limb atherosclerosis groups(n=2515)based on lower limb arterial ultrasonography results.At hospital admission,baseline serum RBP levels were assessed,and all subjects were categorized into three groups(Q1-Q3)based on RBP tertiles.Logistic regression,restricted cubic spline regression,subgroup analysis,and machine learning were used to assess the association between RBP levels and lower limb atherosclerosis risk.RESULTS Among 4428 individuals with T2DM,2515(56.80%)had lower limb atherosclerosis.Logistic analysis showed that lower limb atherosclerosis risk increased by 1%for every 1 unit rise in serum RBP level(odds ratio=1.01,95%confidence interval:1.00-1.02,P=0.004).Patients in the highest tertile group(Q3)had a higher lower limb atherosclerosis risk compared to the lowest tertile group(Q1)(odds ratio=1.36,95%confidence interval:1.12-1.67,P=0.002).The lower limb atherosclerosis risk gradually increased with an increase in RBP tertile(P for trend=0.005).Restricted cubic spline analysis indicated a linear correlation between serum RBP levels and lower limb atherosclerosis risk(non-linear P<0.05).Machine learning demonstrated the significance and diagnostic value of serum RBP in predicting lower limb atherosclerosis risk.CONCLUSION Elevated serum RBP levels correlate with an increased lower limb atherosclerosis risk in individuals with T2DM.
文摘BACKGROUND In 2017,our institution implemented a high efficiency(HE)pathway for lower limb orthopedic surgery.The employed strategy included patient selection,surgical instrument standardization,preoperative surgical nerve blocks,avoidance of general anesthesia and bypassing phase one recovery.We conducted a historic cohort study whose primary outcome was the postoperative recovery time between the HE and traditional(T)pathway.AIM To determine whether the implementation of a HE pathway was correlated with a reduction in postoperative recovery time.METHODS Patients who had unilateral elective lower limb orthopedic procedures through the T and HE pathway were screened between 2017 to 2019.Patients were at least 18 years old,and American Society of Anesthesiologists(ASA)Physical Status I to III without major systemic comorbidities were included.Propensity score was generated using multivariable regression taking age,body mass index,sex,ASA class and surgical type as covariates using nearest neighbour methods between the two pathways.Mann Whitney U test were used to analyzed total postoperative time.RESULTS There was an associated reduction in total postoperative recovery time of 63 minutes(95%CI:-69 to-57)in the HE group.The operating room time and total length of stay also had an associated decrease of 20 minutes(95%CI:-23 to-17)and 84 minutes(95%CI:-92 to-75)respectively.CONCLUSION Utilizing multifaceted strategies to improve perioperative efficiency was associated with a reduction in the postoperative recovery time in our retrospective study.This model can be a potential strategy to deal with surgical backlog in the face of ongoing human resource challenges.
文摘BACKGROUND Lower limb atherosclerotic occlusive disease(LAOD)is a common complication in diabetic patients,leading to significant symptoms and reduced quality of life.AIM To investigate the efficacy of autologous platelet-rich gel(APRG)as an innovative treatment for LAOD,focusing on clinical outcomes such as symptom relief,flow values,ankle-brachial index(ABI),walking distance,and claudication severity.METHODS This retrospective study involved an analysis of electronic medical records(EMR)from 150 patients diagnosed with LAOD.Participants were assigned to either a treatment group(n=80)or a control group(n=70).Both groups received standard care and underwent dressing changes.In addition,the treatment group was given APRG.Primary outcomes included changes in pain levels,wound healing rates,flow values assessed by plethysmography,ABI measurements,walking distance,and claudication severity.Statistical analyses were conducted to determine the significance of the results.RESULTS The APRG group showed significant improvements after 12 weeks,including a 70%reduction in pain,a 65%increase in wound healing rates,and an average walking distance increase of 150 meters.Flow values improved by 20%,with significant enhancements in ABI measurements(P<0.01).Additionally,patient satisfaction was higher,and 60%of patients reported improved claudication severity,confirming the efficacy of APRG in enhancing clinical outcomes for lower LAOD.CONCLUSION The APRG demonstrates significant efficacy in managing LAOD in diabetic patients,improving key clinical parameters including flow values,ABI,walking distance,and claudication.These findings support the need for further prospective studies to validate long-term efficacy and optimize treatment strategies.
基金supported by the Major Sports Research Projects of Jiangsu Provincial Sports Bureau in 2022(No.ST221101).
文摘As an essential tool for quantitative analysis of lower limb coordination,optical motion capture systems with marker-based encoding still suffer from inefficiency,high costs,spatial constraints,and the requirement for multiple markers.While 3D pose estimation algorithms combined with ordinary cameras offer an alternative,their accuracy often deteriorates under significant body occlusion.To address the challenge of insufficient 3D pose estimation precision in occluded scenarios—which hinders the quantitative analysis of athletes’lower-limb coordination—this paper proposes a multimodal training framework integrating spatiotemporal dependency networks with text-semantic guidance.Compared to traditional optical motion capture systems,this work achieves low-cost,high-precision motion parameter acquisition through the following innovations:(1)spatiotemporal dependency attention module is designed to establish dynamic spatiotemporal correlation graphs via cross-frame joint semantic matching,effectively resolving the feature fragmentation issue in existing methods.(2)noise-suppressed multi-scale temporal module is proposed,leveraging KL divergence-based information gain analysis for progressive feature filtering in long-range dependencies,reducing errors by 1.91 mm compared to conventional temporal convolutions.(3)text-pose contrastive learning paradigm is introduced for the first time,where BERT-generated action descriptions align semantic-geometric features via the BERT encoder,significantly enhancing robustness under severe occlusion(50%joint invisibility).On the Human3.6M dataset,the proposed method achieves an MPJPE of 56.21 mm under Protocol 1,outperforming the state-of-the-art baseline MHFormer by 3.3%.Extensive ablation studies on Human3.6M demonstrate the individual contributions of the core modules:the spatiotemporal dependency module and noise-suppressed multi-scale temporal module reduce MPJPE by 0.30 and 0.34 mm,respectively,while the multimodal training strategy further decreases MPJPE by 0.6 mm through text-skeleton contrastive learning.Comparative experiments involving 16 athletes show that the sagittal plane coupling angle measurements of hip-ankle joints differ by less than 1.2°from those obtained via traditional optical systems(two one-sided t-tests,p<0.05),validating real-world reliability.This study provides an AI-powered analytical solution for competitive sports training,serving as a viable alternative to specialized equipment.
基金supported by the National Natural Science Foundation of China(62473337,62003305)the Key Research and Development Program of Zhejiang Province(2024C03040,2022C03029)the funding of Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang Province(2023R01006).
文摘Focusing on the rehabilitation training of hemiplegia patients,this paper proposes a gait-planning strategy based on a central pattern generator and an adaptive time-delay control scheme that utilizes recursive terminal sliding mode for lower limb rehabilitation exoskeleton robots.The central pattern generator network plans a reference gait trajectory for the affected leg,synchronized with the movement of the healthy leg.The proposed adaptive time-delay control scheme possesses a model-independent property due to the mechanism of time-delay estimation,with adaptive control gains that enhance the resilience against system perturbations and a recursive terminal sliding mode control component to achieve a fast convergence rate.According to the Lyapunov stability criterion,it is proved that the gait trajectory-tracking error is uniformly ultimately bounded.Experiments are conducted on a lower limb exoskeleton experimental platform,and the experimental results demonstrate the effectiveness and superiority of the proposed strategies.
文摘Rehabilitation of lower limb amputation in developing countries is quite challenging.Though there are basic to highly advanced prostheses available in India,the set-up is still facing difficulties in developing countries.Prosthetic management is difficult due to lack of availability of prostheses and reduced affordability among low income populations.In this review we highlighted the lower limb amputation and prosthetic rehabilitation status in India.Currently,India is advancing well in the rehabilitation field,but further studies are required to provide more evidence and recommendation.
基金Supported by National Natural Science Foundation of China(Grant No.61273342)Beijing Municipal Natural Science Foundation of China(Grant Nos.3113026,3132005)
文摘Due to the close physical interaction between human and machine in process of gait training, lower limb exoskeletons should be safe, comfortable and able to smoothly transfer desired driving force/moments to the patients. Correlatively, in kinematics the exoskeletons are required to be compatible with human lower limbs and thereby to avoid the uncontrollable interactional loads at the human-machine interfaces. Such requirement makes the structure design of exoskeletons very difficult because the human-machine closed chains are complicated. In addition, both the axis misalignments and the kinematic character difference between the exoskeleton and human joints should be taken into account. By analyzing the DOF（degree of freedom） of the whole human-machine closed chain, the human-machine kinematic incompatibility of lower limb exoskeletons is studied. An effective method for the structure design of lower limb exoskeletons, which are kinematically compatible with human lower limb, is proposed. Applying this method, the structure synthesis of the lower limb exoskeletons containing only one-DOF revolute and prismatic joints is investigated; the feasible basic structures of exoskeletons are developed and classified into three different categories. With the consideration of quasi-anthropopathic feature, structural simplicity and wearable comfort of lower limb exoskeletons, a joint replacement and structure comparison based approach to select the ideal structures of lower limb exoskeletons is proposed, by which three optimal exoskeleton structures are obtained. This paper indicates that the human-machine closed chain formed by the exoskeleton and human lower limb should be an even-constrained kinematic system in order to avoid the uncontrollable human-machine interactional loads. The presented method for the structure design of lower limb exoskeletons is universal and simple, and hence can be applied to other kinds of wearable exoskeletons.
基金supported by the Pre-research project in the manned space field.Project Number 020202,China.
文摘This paper describes a novel gait pattern recognition method based on Long Short-Term Memory(LSTM)and Convolutional Neural Network(CNN)for lower limb exoskeleton.The Inertial Measurement Unit(IMU)installed on the exoskeleton to collect motion information,which is used for LSTM-CNN input.This article considers five common gait patterns,including walking,going up stairs,going down stairs,sitting down,and standing up.In the LSTM-CNN model,the LSTM layer is used to process temporal sequences and the CNN layer is used to extract features.To optimize the deep neural network structure proposed in this paper,some hyperparameter selection experiments were carried out.In addition,to verify the superiority of the proposed recognition method,the method is compared with several common methods such as LSTM,CNN and SVM.The results show that the average recognition accuracy can reach 97.78%,which has a good recognition eff ect.Finally,according to the experimental results of gait pattern switching,the proposed method can identify the switching gait pattern in time,which shows that it has good real-time performance.
基金Supported by National Natural Science Foundation of China(Grant Nos.51775089,12072068,11872147)Sichuan Province Science and Technology Support Program of China(Grant Nos.2020YFG0137,2018JY0565).
文摘In this study,a humanoid prototype of 2-DOF(degrees of freedom)lower limb exoskeleton is introduced to evaluate the wearable comfortable effect between person and exoskeleton.To improve the detection accuracy of the humanrobot interaction torque,a BPNN(backpropagation neural networks)is proposed to estimate this interaction force and to compensate for the measurement error of the 3D-force/torque sensor.Meanwhile,the backstepping controller is designed to realize the exoskeleton's passive position control,which means that the person passively adapts to the exoskeleton.On the other hand,a variable admittance controller is used to implement the exoskeleton's active followup control,which means that the person's motion is motivated by his/her intention and the exoskeleton control tries best to improve the human-robot wearable comfortable performance.To improve the wearable comfortable effect,serval regular gait tasks with different admittance parameters and step frequencies are statistically performed to obtain the optimal admittance control parameters.Finally,the BPNN compensation algorithm and two controllers are verified by the experimental exoskeleton prototype with human-robot cooperative motion.
基金This work is supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.51621004)National Natural Science Foundation of China(Grant No.51875187)+1 种基金Hunan Youth Talent Program(Grant No.2020RC3016)Hunan Provincial Natural Science Foundation of China(Grant No.2019JJ40021).
文摘A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometric differences of the people from different countries,the present study aims to establish and validate a finite element lower limb model representing 50th Chinese male size for pedestrian safety research,then compare its biomechanical responses with the general models currently in wide use in the world for pedestrian safety evaluation.Concerning the vehicle-pedestrian impact loading environment,the previously developed lower limb model with three-dimensional muscles was adjusted and validated through the related experiments.Then,the biomechanical responses of the validated model were compared with the Total Human Model for Safety(THUMS)and Advanced Pedestrian Legform Impactor(aPLI)models by combing with four typical vehicles.The results showed that both consistency and significant differences of biomechanical responses existed between the present model and the other two models.The injury measurements of the thigh region of the present model showed extremely large differences with the other two models,while the tibia and Medial Collateral Ligament(MCL)injury measurements show similar values.Thus,it can be concluded that directly using the aPLI or THUMS models for Chinese pedestrian safety evaluation is not robust concerning both kinematic responses and injury measurements.
