Humanoid robots are a hot topic in the field of robotics research. The walking system is the critical part of the humanoid robot, and the dynamic simulation of the walking system is of great importance. In this paper,...Humanoid robots are a hot topic in the field of robotics research. The walking system is the critical part of the humanoid robot, and the dynamic simulation of the walking system is of great importance. In this paper, the stability of the walking system and the rationality of its structural design are considered in the study of dynamics for a humanoid robot. The dynamic model of humanoid robot walking system is established by using the Lagrange dynamics method. Additionally, the three-dimensional model of CATIA is imported into ADAMS. The humanoid robot walking system is added with the movement of the deputy and the driving force in the ADAMS.The torque and angular velocity of the ankle joint and hip joint are analyzed in the process of knee bends. The simulation results show that the overall performance of the humanoid robot walking system is favorable and has a smooth movement, and the specified actions can be completed, which proves the rationality of the humanoid robot walking system design.展开更多
A new explosion-proof walking system was designed for the coal mine rescue robot(CMRR) by optimizing the mechanical structure and control algorithm. The mechanical structure innovation lies mainly in the dual-motor dr...A new explosion-proof walking system was designed for the coal mine rescue robot(CMRR) by optimizing the mechanical structure and control algorithm. The mechanical structure innovation lies mainly in the dual-motor drive tracked unit used, which showed high dynamic performance compared with the conventional tracked unit. The control algorithm, developed based on decision trees and neural networking, facilitates autonomous switching between "Velocity-driven Mode" and "Torquedriven Mode". To verify the feasibility and effectiveness of the control strategy, we built a self-designed test platform and used it to debug the control program; we then made a robot prototype and conducted further experiments on single-step, ramp, and rubble terrains. The results show that the proposed walking system has excellent dynamic performance and the control strategy is very efficient, suggesting that a robot with this type of explosion-proof walking system can be successfully applied in Chinese coal mines.展开更多
Background In virtual environments(VEs),users can explore a large virtual scene through the viewpoint operation of a head-mounted display(HMD)and movement gains combined with redirected walking technology.The existing...Background In virtual environments(VEs),users can explore a large virtual scene through the viewpoint operation of a head-mounted display(HMD)and movement gains combined with redirected walking technology.The existing redirection methods and viewpoint operations are effective in the horizontal direction;however,they cannot help participants experience immersion in the vertical direction.To improve the immersion of upslope walking,this study presents a virtual climbing system based on passive haptics.Methods This virtual climbing system uses the tactile feedback provided by sponges,a commonly used flexible material,to simulate the tactile sense of a user's soles.In addition,the visual stimulus of the HMD,the tactile feedback of the flexible material,and the operation of the user's walking in a VE combined with redirection technology are all adopted to enhance the user's perception in a VE.In the experiments,a physical space with a hard-flat floor and three types of sponges with thicknesses of 3,5,and 8cm were utilized.Results We recruited 40 volunteers to conduct these experiments,and the results showed that a thicker flexible material increases the difficulty for users to roam and walk within a certain range.Conclusion The virtual climbing system can enhance users'perception of upslope walking in a VE.展开更多
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec...BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function.展开更多
[Objectives]To synthesize evidence on HIIT versus moderate-intensity continuous training(MICT)or routine rehabilitation in stroke survivors.[Methods]We systematically searched 8 databases(PubMed,EMBASE,CENTRAL,Web of ...[Objectives]To synthesize evidence on HIIT versus moderate-intensity continuous training(MICT)or routine rehabilitation in stroke survivors.[Methods]We systematically searched 8 databases(PubMed,EMBASE,CENTRAL,Web of Science,SPORTSDiscus,PsycINFO,SCOPUS,CINAHL)up to May 2025.Seventeen randomized controlled trials(RCTs;total n=1142)met inclusion criteria:adults with stroke,device-based HIIT(≥70%HRR/VO 2peak),and outcomes assessing VO_(2)peak,6-min walk distance(6MWD),or Berg Balance Scale(BBS).Methodological quality was evaluated using the PEDro scale.Pooled effect sizes(Hedges'g)were calculated via random-effects models,with heterogeneity quantified by I^(2).[Results]HIIT significantly improved peak oxygen uptake(VO_(2)peak)versus controls(g=0.59,95%CI:0.44-0.75,p<0.001;I^(2)=16.29%).Low heterogeneity and symmetrical funnel plots supported robustness.HIIT also enhanced walking endurance(6MWD:g=0.32,95%CI:0.16-0.48,p<0.01;I^(2)=30%).In contrast,no significant benefit was observed for balance function(BBS:g=0.07,95%CI:-0.13-0.26,p=0.50;I^(2)=0%).[Conclusions]HIIT is a safe and highly effective intervention for enhancing aerobic capacity and walking function post-stroke.Its benefits are maximized at higher intensities and longer durations but do not extend to balance improvement.Integrating HIIT into stroke rehabilitation protocols is strongly recommended to promote functional independence.展开更多
Background The redirected walking(RDW)method for multi-user collaboration requires maintaining the relative position between users in a virtual environment(VE)and physical environment(PE).A chasing game in a VE is a t...Background The redirected walking(RDW)method for multi-user collaboration requires maintaining the relative position between users in a virtual environment(VE)and physical environment(PE).A chasing game in a VE is a typical virtual reality game that entails multi-user collaboration.When a user approaches and interacts with a target user in the VE,the user is expected to approach and interact with the target user in the corresponding PE as well.Existing methods of multi-user RDW mainly focus on obstacle avoidance,which does not account for the relative positional relationship between the users in both VE and PE.Methods To enhance the user experience and facilitate potential interaction,this paper presents a novel dynamic alignment algorithm for multi-user collaborative redirected walking(DA-RDW)in a shared PE where the target user and other users are moving.This algorithm adopts improved artificial potential fields,where the repulsive force is a function of the relative position and velocity of the user with respect to dynamic obstacles.For the best alignment,this algorithm sets the alignment-guidance force in several cases and then converts it into a constrained optimization problem to obtain the optimal direction.Moreover,this algorithm introduces a potential interaction object selection strategy for a dynamically uncertain environment to speed up the subsequent alignment.To balance obstacle avoidance and alignment,this algorithm uses the dynamic weightings of the virtual and physical distances between users and the target to determine the resultant force vector.Results The efficacy of the proposed method was evaluated using a series of simulations and live-user experiments.The experimental results demonstrate that our novel dynamic alignment method for multi-user collaborative redirected walking can reduce the distance error in both VE and PE to improve alignment with fewer collisions.展开更多
The main goal of spinal cord rehabilitation is to restore walking ability and improve walking quality after spinal cord injury(SCI). The spatiotemporal parameters of walking and the parameters of plantar pressure can ...The main goal of spinal cord rehabilitation is to restore walking ability and improve walking quality after spinal cord injury(SCI). The spatiotemporal parameters of walking and the parameters of plantar pressure can be obtained using a plantar pressure analysis system. Previous studies have reported step asymmetry in patients with bilateral SCI. However, the asymmetry of other parameters in patients with SCI has not been reported. This was a prospective, cross-sectional study, which included 23 patients with SCI, aged 48.1 ± 14.5 years, and 28 healthy subjects, aged 47.1 ± 9.8 years. All subjects underwent bare foot walking on a plantar pressure measurement device to measure walking speed and spatiotemporal parameters. Compared with healthy subjects, SCI patients had slower walking speed, longer stride time and stance time, larger stance phase percentage, and shorter stride length. The peak pressures under the metatarsal heads and toe were lower in SCI patients than in healthy subjects. In the heel, regional impulse and the contact area percentage in SCI patients were higher than those in healthy subjects. The symmetry indexes of stance time, step length, maximum force, impulse and contact area were increased in SCI patients, indicating a decline in symmetry. The results confirm that the gait quality, including spatiotemporal variables and plantar pressure parameters, and symmetry index were lower in SCI patients compared with healthy subjects. Plantar pressure parameters and symmetry index could be sensitive quantitative parameters to improve gait quality of SCI patients. The protocols were approved by the Clinical Research Ethics Committee of Shengjing Hospital of China Medical University(approval No. 2015 PS54 J) on August 13, 2015. This trial was registered in the ISRCTN Registry(ISRCTN42544587) on August 22, 2018. Protocol version: 1.0.展开更多
This paper presents a novel design of minimalist bipedal walking robot with flexible ankle and split-mass balancing systems.The proposed approach implements a novel strategy to achieve stable bipedal walk by decouplin...This paper presents a novel design of minimalist bipedal walking robot with flexible ankle and split-mass balancing systems.The proposed approach implements a novel strategy to achieve stable bipedal walk by decoupling the walking motion control from the sideway balancing control.This strategy allows the walking controller to execute the walking task independently while the sideway balancing controller continuously maintains the balance of the robot.The hip-mass carry approach and selected stages of walk implemented in the control strategy can minimize the efect of major hip mass of the robot on the stability of its walk.In addition,the developed smooth joint trajectory planning eliminates the impacts of feet during the landing.In this paper,the new design of mechanism for locomotion systems and balancing systems are introduced.An additional degree of freedom introduced at the ankle joint increases the sensitivity of the system and response time to the sideway disturbances.The efectiveness of the proposed strategy is experimentally tested on a bipedal robot prototype.The experimental results provide evidence that the proposed strategy is feasible and advantageous.展开更多
For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein th...For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein thrombosis.Surgery is rarely perfo rmed on spinal co rd injury in the chronic phase,and few treatments have been proven effective in chronic spinal cord injury patients.Development of effective therapies fo r chronic spinal co rd injury patients is needed.We conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal co rd injury to compare intensive rehabilitation(weight-bearing walking training)alone with surgical intervention plus intensive rehabilitation.This clinical trial was registered at ClinicalTrials.gov(NCT02663310).The goal of surgical intervention was spinal cord detethering,restoration of cerebrospinal fluid flow,and elimination of residual spinal cord compression.We found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement,reduced spasticity,and more rapid bowel and bladder functional recovery than weight-bearing walking training alone.Overall,the surgical procedures and intensive rehabilitation were safe.American Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 injuries.Surgery combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients.展开更多
In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assi...In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assistive system is proposed and investigated in this research.In contrast to tradition,it innovatively utilizes an ultrasonic motor and a wire-driven series elastic mechanism to achieve superior system performances in aspects of simple structure,high torque/weight ratio,quiet operation,quick response,favorable electromagnetic compatibility,strong shock resistance,better safety,and accurately stable force control.The proposed device is mainly composed of an ultrasonic motor,a linear spring,a steel wire,four pulleys and one rotating part.To overcome the ultrasonic motor's insufficient output torque,a steel wire and pulleys are smartly combined to directly magnify the torque instead of using a conventional gear reducer.Among the pulleys,there is one tailored pulley playing an important role to keep the reduction ratio as 4.5 constantly.Meanwhile,the prototype is manufactured and its actual performance is verified by experimental results.In a one-second operating cycle,it only takes 86 ms for this mechanism to output an assistive torque of 1.6 N·m.At this torque,the ultrasonic motor's speed is around 4.1 rad/s.Moreover,experiments with different operation periods have been conducted for different application scenarios.This study provides a useful idea for the application of ultrasonic motor in walking assistance system.展开更多
Gait recognition is the key question of functional electrical stimulation (FES) system control for paraplegic walking. A new risk-tendency-graph (RTG) method was proposed to recognize the stability information in FES-...Gait recognition is the key question of functional electrical stimulation (FES) system control for paraplegic walking. A new risk-tendency-graph (RTG) method was proposed to recognize the stability information in FES-assisted walking gait. The main instrument was a specialized walker dynamometer system based on a multi-channel strain-gauge bridge network fixed on the walker frame. During walking process, this system collected the reaction forces between patient's upper extremities and walker and converted them into RTG morphologic curves of dynamic gait stability in temporal and spatial domains. To demonstrate the potential usefulness of RTG, preliminary clinical trials were done with paraplegic patients. The gait stability levels of two walking cases with 4- and 12-week FES training from one subject were quantified (0.43 and 0.19) from the results of temporal and spatial RTG. Relevant instable phases in gait cycle and dangerous inclinations of patient's body during walking process were also brought forward. In conclusion, the new RTG method is practical for distinguishing more useful gait stability information for FES system control.展开更多
In the past few decades,people have been trying to address the issue of walking instability in bipedal robots in uncertain environments.However,most control methods currently have still failed to achieve robust walkin...In the past few decades,people have been trying to address the issue of walking instability in bipedal robots in uncertain environments.However,most control methods currently have still failed to achieve robust walking of bipedal robots under uncertain disturbances.Existing research mostly focuses on motion control methods for robots on uneven terrain and under sudden impact forces,with little consideration for the problem of continuous and intense external force disturbances in uncertain environments.In response to this issue,a disturbance-robust control method based on adaptive feedback compensation is proposed.First,based on the Lagrangian method,the dynamic model of a bipedal robot under different types of external force disturbances was established.Subsequently,through dynamic analysis,it was observed that classical control methods based on hybrid zero dynamics failed to consider the continuous and significant external force disturbances in uncertain environments.Therefore,an adaptive feedback compensation controller was designed,and an adaptive parameter adjustment optimization algorithm was proposed based on walking constraints to achieve stable walking of bipedal robots under different external force disturbances.Finally,in numerical simulation experiments,comparative analysis revealed that using only a controller based on hybrid zero dynamics was insufficient to converge the motion of a planar five-link bipedal robot subjected to periodic forces or bounded noise disturbances to a stable state.In contrast,in the adaptive feedback compensation control method,the use of an adaptive parameter adjustment optimization algorithm to generate time-varying control parameters successfully achieved stable walking of the robot under these disturbances.This indicates the effectiveness of the adaptive parameter adjustment algorithm and the robustness of the adaptive feedback compensation control method.展开更多
This research paper presents a comprehensive investigation into the effectiveness of the DeepSurNet-NSGA II(Deep Surrogate Model-Assisted Non-dominated Sorting Genetic Algorithm II)for solving complex multiobjective o...This research paper presents a comprehensive investigation into the effectiveness of the DeepSurNet-NSGA II(Deep Surrogate Model-Assisted Non-dominated Sorting Genetic Algorithm II)for solving complex multiobjective optimization problems,with a particular focus on robotic leg-linkage design.The study introduces an innovative approach that integrates deep learning-based surrogate models with the robust Non-dominated Sorting Genetic Algorithm II,aiming to enhance the efficiency and precision of the optimization process.Through a series of empirical experiments and algorithmic analyses,the paper demonstrates a high degree of correlation between solutions generated by the DeepSurNet-NSGA II and those obtained from direct experimental methods,underscoring the algorithm’s capability to accurately approximate the Pareto-optimal frontier while significantly reducing computational demands.The methodology encompasses a detailed exploration of the algorithm’s configuration,the experimental setup,and the criteria for performance evaluation,ensuring the reproducibility of results and facilitating future advancements in the field.The findings of this study not only confirm the practical applicability and theoretical soundness of the DeepSurNet-NSGA II in navigating the intricacies of multi-objective optimization but also highlight its potential as a transformative tool in engineering and design optimization.By bridging the gap between complex optimization challenges and achievable solutions,this research contributes valuable insights into the optimization domain,offering a promising direction for future inquiries and technological innovations.展开更多
The anterior cruciate ligament plays a crucial role in maintaining stability within the knee joint,particularly for athletes who frequently experience its rupture.This study presents a novel approach using personalize...The anterior cruciate ligament plays a crucial role in maintaining stability within the knee joint,particularly for athletes who frequently experience its rupture.This study presents a novel approach using personalized three-dimensional(3D)parametric finite element modeling of the knee joint to simulate the treatment following anterior cruciate ligament reconstruction(ACLR)in both forward walking(FW)and drop landing(DL)tasks.The study encompasses two distinct cohorts:five healthy athletes and five ACLR patients.Biomechanical motion analysis was conducted on both cohorts,with the ACLR patient group evaluated at 6 and 9 months post-surgery.A comprehensive 3D parametric model of the knee joint was meticulously crafted.The findings reveal a notable reduction in stress on crucial knee structures such as the autograft,meniscus,and cartilages over time for both FW and DL tasks following ACLR,with a reduction in tissue tension of approximately 9.5%and 37%for FW and DL,respectively.This personalized model not only facilitates the investigation of knee joint tissue biomechanics post-ACLR but also aids in estimating the return-to-sports timeline for patients.By accommodating individual tissue geometries and incorporating patient-specific kinetic data,this model enhances our comprehension of post-ACLR biomechanics across various functional tasks,thereby optimizing rehabilitation strategies.展开更多
Objectives Understanding differences between real-world walking speed(RWS)and laboratory-measured walking speed(LWS)is crucial for comprehensive mobility assessments,especially in context of prolonged immobilization.T...Objectives Understanding differences between real-world walking speed(RWS)and laboratory-measured walking speed(LWS)is crucial for comprehensive mobility assessments,especially in context of prolonged immobilization.This study aimed to investigate disparities in walking speed following a 60-day bed-rest period.Methods In 11 male participants,RWS was continuously monitored using a tri-axial accelerometer worn on the waist,while LWS was assessed via a 10-m walk test at preferred speed,on three different study days after immobilization.Statistical analyses included Bland–Altman and Pearson’s correlation to evaluate agreement between RWS and LWS,alongside paired-sample t-tests and univariate linear regression models to assess significance of differences and temporal effects on gait speed.Results Results of Bland-Altman analysis showed no agreement between RWS and LWS(mean difference 0.77 m/s)and nonsignificant correlation(r=0.19,p-value=0.3).Paired-sample t-tests indicated significantly lower RWS compared to LWS for all study days(p-value<0.001).Univariate linear regression models demonstrated a significant effect of test day on RWS(p-value<0.001)but not on LWS(p-value=0.23).Conclusions These findings emphasize the importance of integrating both assessments to capture comprehensive mobility changes following prolonged periods of inactivity.Particularly significant is that RWS is constantly lower than LWS,with the former being more representative as it reflects what normally participants would do when not under observation.Lastly,understanding discrepancies between RWS and LWS would allow for more appropriate rehabilitation programs to speed up recovery while simultaneously keeping the rehabilitation safe and tailored.展开更多
Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study ...Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study adopted a quasi-experimental research design,specifically a non-equivalent control group pre-test and post-test design.Utilizing the Exercise of Self-Care Agency Scale(ESCA)and Care Dependency Scale(CDS),a survey was administered to 64 patients from a hospital in Shandong Province.The statistical methods used for analyzing data included frequency,mean,standard deviation(SD),independent t-test,P-value calculation,and dependent t-test.Result:After two months of a brisk walking exercise program,participants in the experimental group had a higher level of self-care agency than before the experiment(P<0.05),and their level of care dependency was significantly reduced(P<0.05).Participants in the control group also showed higher levels of self-care agency(P<0.05)and lower levels of care dependency(P<0.05)after two months compared to their levels before the two months.Conclusion:The brisk walking program had a positive impact on patients’self-care agency and reduced their care dependency.展开更多
基金the Jilin Province Science and Technology Development Project(No.20150309005YY)the National Natural Science Foundation of China(No.51875047)
文摘Humanoid robots are a hot topic in the field of robotics research. The walking system is the critical part of the humanoid robot, and the dynamic simulation of the walking system is of great importance. In this paper, the stability of the walking system and the rationality of its structural design are considered in the study of dynamics for a humanoid robot. The dynamic model of humanoid robot walking system is established by using the Lagrange dynamics method. Additionally, the three-dimensional model of CATIA is imported into ADAMS. The humanoid robot walking system is added with the movement of the deputy and the driving force in the ADAMS.The torque and angular velocity of the ankle joint and hip joint are analyzed in the process of knee bends. The simulation results show that the overall performance of the humanoid robot walking system is favorable and has a smooth movement, and the specified actions can be completed, which proves the rationality of the humanoid robot walking system design.
基金Project(2012AA041504)supported by the National High-Tech Research and Development Program of ChinaProject(KYLX15_1418)supported by the 2015 Annual General University Graduate Research and Innovation Program of Jiangsu Province,ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘A new explosion-proof walking system was designed for the coal mine rescue robot(CMRR) by optimizing the mechanical structure and control algorithm. The mechanical structure innovation lies mainly in the dual-motor drive tracked unit used, which showed high dynamic performance compared with the conventional tracked unit. The control algorithm, developed based on decision trees and neural networking, facilitates autonomous switching between "Velocity-driven Mode" and "Torquedriven Mode". To verify the feasibility and effectiveness of the control strategy, we built a self-designed test platform and used it to debug the control program; we then made a robot prototype and conducted further experiments on single-step, ramp, and rubble terrains. The results show that the proposed walking system has excellent dynamic performance and the control strategy is very efficient, suggesting that a robot with this type of explosion-proof walking system can be successfully applied in Chinese coal mines.
基金the National Key R&D Program of China(2018YFB1404100)National Natural Science Foundation of China(62072405)Zhejiang Provincial Natural Science Foundation of China(LGF20F020017).
文摘Background In virtual environments(VEs),users can explore a large virtual scene through the viewpoint operation of a head-mounted display(HMD)and movement gains combined with redirected walking technology.The existing redirection methods and viewpoint operations are effective in the horizontal direction;however,they cannot help participants experience immersion in the vertical direction.To improve the immersion of upslope walking,this study presents a virtual climbing system based on passive haptics.Methods This virtual climbing system uses the tactile feedback provided by sponges,a commonly used flexible material,to simulate the tactile sense of a user's soles.In addition,the visual stimulus of the HMD,the tactile feedback of the flexible material,and the operation of the user's walking in a VE combined with redirection technology are all adopted to enhance the user's perception in a VE.In the experiments,a physical space with a hard-flat floor and three types of sponges with thicknesses of 3,5,and 8cm were utilized.Results We recruited 40 volunteers to conduct these experiments,and the results showed that a thicker flexible material increases the difficulty for users to roam and walk within a certain range.Conclusion The virtual climbing system can enhance users'perception of upslope walking in a VE.
文摘BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function.
文摘[Objectives]To synthesize evidence on HIIT versus moderate-intensity continuous training(MICT)or routine rehabilitation in stroke survivors.[Methods]We systematically searched 8 databases(PubMed,EMBASE,CENTRAL,Web of Science,SPORTSDiscus,PsycINFO,SCOPUS,CINAHL)up to May 2025.Seventeen randomized controlled trials(RCTs;total n=1142)met inclusion criteria:adults with stroke,device-based HIIT(≥70%HRR/VO 2peak),and outcomes assessing VO_(2)peak,6-min walk distance(6MWD),or Berg Balance Scale(BBS).Methodological quality was evaluated using the PEDro scale.Pooled effect sizes(Hedges'g)were calculated via random-effects models,with heterogeneity quantified by I^(2).[Results]HIIT significantly improved peak oxygen uptake(VO_(2)peak)versus controls(g=0.59,95%CI:0.44-0.75,p<0.001;I^(2)=16.29%).Low heterogeneity and symmetrical funnel plots supported robustness.HIIT also enhanced walking endurance(6MWD:g=0.32,95%CI:0.16-0.48,p<0.01;I^(2)=30%).In contrast,no significant benefit was observed for balance function(BBS:g=0.07,95%CI:-0.13-0.26,p=0.50;I^(2)=0%).[Conclusions]HIIT is a safe and highly effective intervention for enhancing aerobic capacity and walking function post-stroke.Its benefits are maximized at higher intensities and longer durations but do not extend to balance improvement.Integrating HIIT into stroke rehabilitation protocols is strongly recommended to promote functional independence.
基金Supported by STI 2030 Major Projects of China(2021ZD0200400).
文摘Background The redirected walking(RDW)method for multi-user collaboration requires maintaining the relative position between users in a virtual environment(VE)and physical environment(PE).A chasing game in a VE is a typical virtual reality game that entails multi-user collaboration.When a user approaches and interacts with a target user in the VE,the user is expected to approach and interact with the target user in the corresponding PE as well.Existing methods of multi-user RDW mainly focus on obstacle avoidance,which does not account for the relative positional relationship between the users in both VE and PE.Methods To enhance the user experience and facilitate potential interaction,this paper presents a novel dynamic alignment algorithm for multi-user collaborative redirected walking(DA-RDW)in a shared PE where the target user and other users are moving.This algorithm adopts improved artificial potential fields,where the repulsive force is a function of the relative position and velocity of the user with respect to dynamic obstacles.For the best alignment,this algorithm sets the alignment-guidance force in several cases and then converts it into a constrained optimization problem to obtain the optimal direction.Moreover,this algorithm introduces a potential interaction object selection strategy for a dynamically uncertain environment to speed up the subsequent alignment.To balance obstacle avoidance and alignment,this algorithm uses the dynamic weightings of the virtual and physical distances between users and the target to determine the resultant force vector.Results The efficacy of the proposed method was evaluated using a series of simulations and live-user experiments.The experimental results demonstrate that our novel dynamic alignment method for multi-user collaborative redirected walking can reduce the distance error in both VE and PE to improve alignment with fewer collisions.
基金supported by the New Technique Project of Shengjing Hospital of China Medical University,China,No.2015-117(to XNY)
文摘The main goal of spinal cord rehabilitation is to restore walking ability and improve walking quality after spinal cord injury(SCI). The spatiotemporal parameters of walking and the parameters of plantar pressure can be obtained using a plantar pressure analysis system. Previous studies have reported step asymmetry in patients with bilateral SCI. However, the asymmetry of other parameters in patients with SCI has not been reported. This was a prospective, cross-sectional study, which included 23 patients with SCI, aged 48.1 ± 14.5 years, and 28 healthy subjects, aged 47.1 ± 9.8 years. All subjects underwent bare foot walking on a plantar pressure measurement device to measure walking speed and spatiotemporal parameters. Compared with healthy subjects, SCI patients had slower walking speed, longer stride time and stance time, larger stance phase percentage, and shorter stride length. The peak pressures under the metatarsal heads and toe were lower in SCI patients than in healthy subjects. In the heel, regional impulse and the contact area percentage in SCI patients were higher than those in healthy subjects. The symmetry indexes of stance time, step length, maximum force, impulse and contact area were increased in SCI patients, indicating a decline in symmetry. The results confirm that the gait quality, including spatiotemporal variables and plantar pressure parameters, and symmetry index were lower in SCI patients compared with healthy subjects. Plantar pressure parameters and symmetry index could be sensitive quantitative parameters to improve gait quality of SCI patients. The protocols were approved by the Clinical Research Ethics Committee of Shengjing Hospital of China Medical University(approval No. 2015 PS54 J) on August 13, 2015. This trial was registered in the ISRCTN Registry(ISRCTN42544587) on August 22, 2018. Protocol version: 1.0.
文摘This paper presents a novel design of minimalist bipedal walking robot with flexible ankle and split-mass balancing systems.The proposed approach implements a novel strategy to achieve stable bipedal walk by decoupling the walking motion control from the sideway balancing control.This strategy allows the walking controller to execute the walking task independently while the sideway balancing controller continuously maintains the balance of the robot.The hip-mass carry approach and selected stages of walk implemented in the control strategy can minimize the efect of major hip mass of the robot on the stability of its walk.In addition,the developed smooth joint trajectory planning eliminates the impacts of feet during the landing.In this paper,the new design of mechanism for locomotion systems and balancing systems are introduced.An additional degree of freedom introduced at the ankle joint increases the sensitivity of the system and response time to the sideway disturbances.The efectiveness of the proposed strategy is experimentally tested on a bipedal robot prototype.The experimental results provide evidence that the proposed strategy is feasible and advantageous.
基金supported by Hong Kong Spinal Cord Injury Fund (HKSCIF),China (to HZ)。
文摘For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein thrombosis.Surgery is rarely perfo rmed on spinal co rd injury in the chronic phase,and few treatments have been proven effective in chronic spinal cord injury patients.Development of effective therapies fo r chronic spinal co rd injury patients is needed.We conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal co rd injury to compare intensive rehabilitation(weight-bearing walking training)alone with surgical intervention plus intensive rehabilitation.This clinical trial was registered at ClinicalTrials.gov(NCT02663310).The goal of surgical intervention was spinal cord detethering,restoration of cerebrospinal fluid flow,and elimination of residual spinal cord compression.We found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement,reduced spasticity,and more rapid bowel and bladder functional recovery than weight-bearing walking training alone.Overall,the surgical procedures and intensive rehabilitation were safe.American Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 injuries.Surgery combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients.
基金Supported by China Scholarship Council(Grant No.202006830033),Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)of China.
文摘In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assistive system is proposed and investigated in this research.In contrast to tradition,it innovatively utilizes an ultrasonic motor and a wire-driven series elastic mechanism to achieve superior system performances in aspects of simple structure,high torque/weight ratio,quiet operation,quick response,favorable electromagnetic compatibility,strong shock resistance,better safety,and accurately stable force control.The proposed device is mainly composed of an ultrasonic motor,a linear spring,a steel wire,four pulleys and one rotating part.To overcome the ultrasonic motor's insufficient output torque,a steel wire and pulleys are smartly combined to directly magnify the torque instead of using a conventional gear reducer.Among the pulleys,there is one tailored pulley playing an important role to keep the reduction ratio as 4.5 constantly.Meanwhile,the prototype is manufactured and its actual performance is verified by experimental results.In a one-second operating cycle,it only takes 86 ms for this mechanism to output an assistive torque of 1.6 N·m.At this torque,the ultrasonic motor's speed is around 4.1 rad/s.Moreover,experiments with different operation periods have been conducted for different application scenarios.This study provides a useful idea for the application of ultrasonic motor in walking assistance system.
基金Supported by National Natural Science Foundation of China (No.60501005)Key Programof Tianjin Science Technology Support Plan(No.2007-68)
文摘Gait recognition is the key question of functional electrical stimulation (FES) system control for paraplegic walking. A new risk-tendency-graph (RTG) method was proposed to recognize the stability information in FES-assisted walking gait. The main instrument was a specialized walker dynamometer system based on a multi-channel strain-gauge bridge network fixed on the walker frame. During walking process, this system collected the reaction forces between patient's upper extremities and walker and converted them into RTG morphologic curves of dynamic gait stability in temporal and spatial domains. To demonstrate the potential usefulness of RTG, preliminary clinical trials were done with paraplegic patients. The gait stability levels of two walking cases with 4- and 12-week FES training from one subject were quantified (0.43 and 0.19) from the results of temporal and spatial RTG. Relevant instable phases in gait cycle and dangerous inclinations of patient's body during walking process were also brought forward. In conclusion, the new RTG method is practical for distinguishing more useful gait stability information for FES system control.
基金supported by the National Natural Science Foundation of China(Grant No.12332003)CIE-Tencent Robotics X Rhino-Bird Focused Research Program,and Zhejiang Provincial Natural Science Foundation of China(Grant No.LY23E050010).
文摘In the past few decades,people have been trying to address the issue of walking instability in bipedal robots in uncertain environments.However,most control methods currently have still failed to achieve robust walking of bipedal robots under uncertain disturbances.Existing research mostly focuses on motion control methods for robots on uneven terrain and under sudden impact forces,with little consideration for the problem of continuous and intense external force disturbances in uncertain environments.In response to this issue,a disturbance-robust control method based on adaptive feedback compensation is proposed.First,based on the Lagrangian method,the dynamic model of a bipedal robot under different types of external force disturbances was established.Subsequently,through dynamic analysis,it was observed that classical control methods based on hybrid zero dynamics failed to consider the continuous and significant external force disturbances in uncertain environments.Therefore,an adaptive feedback compensation controller was designed,and an adaptive parameter adjustment optimization algorithm was proposed based on walking constraints to achieve stable walking of bipedal robots under different external force disturbances.Finally,in numerical simulation experiments,comparative analysis revealed that using only a controller based on hybrid zero dynamics was insufficient to converge the motion of a planar five-link bipedal robot subjected to periodic forces or bounded noise disturbances to a stable state.In contrast,in the adaptive feedback compensation control method,the use of an adaptive parameter adjustment optimization algorithm to generate time-varying control parameters successfully achieved stable walking of the robot under these disturbances.This indicates the effectiveness of the adaptive parameter adjustment algorithm and the robustness of the adaptive feedback compensation control method.
文摘This research paper presents a comprehensive investigation into the effectiveness of the DeepSurNet-NSGA II(Deep Surrogate Model-Assisted Non-dominated Sorting Genetic Algorithm II)for solving complex multiobjective optimization problems,with a particular focus on robotic leg-linkage design.The study introduces an innovative approach that integrates deep learning-based surrogate models with the robust Non-dominated Sorting Genetic Algorithm II,aiming to enhance the efficiency and precision of the optimization process.Through a series of empirical experiments and algorithmic analyses,the paper demonstrates a high degree of correlation between solutions generated by the DeepSurNet-NSGA II and those obtained from direct experimental methods,underscoring the algorithm’s capability to accurately approximate the Pareto-optimal frontier while significantly reducing computational demands.The methodology encompasses a detailed exploration of the algorithm’s configuration,the experimental setup,and the criteria for performance evaluation,ensuring the reproducibility of results and facilitating future advancements in the field.The findings of this study not only confirm the practical applicability and theoretical soundness of the DeepSurNet-NSGA II in navigating the intricacies of multi-objective optimization but also highlight its potential as a transformative tool in engineering and design optimization.By bridging the gap between complex optimization challenges and achievable solutions,this research contributes valuable insights into the optimization domain,offering a promising direction for future inquiries and technological innovations.
文摘The anterior cruciate ligament plays a crucial role in maintaining stability within the knee joint,particularly for athletes who frequently experience its rupture.This study presents a novel approach using personalized three-dimensional(3D)parametric finite element modeling of the knee joint to simulate the treatment following anterior cruciate ligament reconstruction(ACLR)in both forward walking(FW)and drop landing(DL)tasks.The study encompasses two distinct cohorts:five healthy athletes and five ACLR patients.Biomechanical motion analysis was conducted on both cohorts,with the ACLR patient group evaluated at 6 and 9 months post-surgery.A comprehensive 3D parametric model of the knee joint was meticulously crafted.The findings reveal a notable reduction in stress on crucial knee structures such as the autograft,meniscus,and cartilages over time for both FW and DL tasks following ACLR,with a reduction in tissue tension of approximately 9.5%and 37%for FW and DL,respectively.This personalized model not only facilitates the investigation of knee joint tissue biomechanics post-ACLR but also aids in estimating the return-to-sports timeline for patients.By accommodating individual tissue geometries and incorporating patient-specific kinetic data,this model enhances our comprehension of post-ACLR biomechanics across various functional tasks,thereby optimizing rehabilitation strategies.
文摘Objectives Understanding differences between real-world walking speed(RWS)and laboratory-measured walking speed(LWS)is crucial for comprehensive mobility assessments,especially in context of prolonged immobilization.This study aimed to investigate disparities in walking speed following a 60-day bed-rest period.Methods In 11 male participants,RWS was continuously monitored using a tri-axial accelerometer worn on the waist,while LWS was assessed via a 10-m walk test at preferred speed,on three different study days after immobilization.Statistical analyses included Bland–Altman and Pearson’s correlation to evaluate agreement between RWS and LWS,alongside paired-sample t-tests and univariate linear regression models to assess significance of differences and temporal effects on gait speed.Results Results of Bland-Altman analysis showed no agreement between RWS and LWS(mean difference 0.77 m/s)and nonsignificant correlation(r=0.19,p-value=0.3).Paired-sample t-tests indicated significantly lower RWS compared to LWS for all study days(p-value<0.001).Univariate linear regression models demonstrated a significant effect of test day on RWS(p-value<0.001)but not on LWS(p-value=0.23).Conclusions These findings emphasize the importance of integrating both assessments to capture comprehensive mobility changes following prolonged periods of inactivity.Particularly significant is that RWS is constantly lower than LWS,with the former being more representative as it reflects what normally participants would do when not under observation.Lastly,understanding discrepancies between RWS and LWS would allow for more appropriate rehabilitation programs to speed up recovery while simultaneously keeping the rehabilitation safe and tailored.
文摘Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study adopted a quasi-experimental research design,specifically a non-equivalent control group pre-test and post-test design.Utilizing the Exercise of Self-Care Agency Scale(ESCA)and Care Dependency Scale(CDS),a survey was administered to 64 patients from a hospital in Shandong Province.The statistical methods used for analyzing data included frequency,mean,standard deviation(SD),independent t-test,P-value calculation,and dependent t-test.Result:After two months of a brisk walking exercise program,participants in the experimental group had a higher level of self-care agency than before the experiment(P<0.05),and their level of care dependency was significantly reduced(P<0.05).Participants in the control group also showed higher levels of self-care agency(P<0.05)and lower levels of care dependency(P<0.05)after two months compared to their levels before the two months.Conclusion:The brisk walking program had a positive impact on patients’self-care agency and reduced their care dependency.
