Ying Chao,born in the 1990s in Jiaxing City of east China’s Zhejiang Province,is of the opinion that traditional agricultural methods cannot meet the demands of modern farming.He plans to change agricultural practice...Ying Chao,born in the 1990s in Jiaxing City of east China’s Zhejiang Province,is of the opinion that traditional agricultural methods cannot meet the demands of modern farming.He plans to change agricultural practices and follow the road of mechanisation after taking part in a one-year vocational training course on drones in Jiaxing Vocational and Technical College in 2021.In fact,more and more young people like Ying are applying digital technology and big data to agricultural production and rural development.And the government has laid out plans to encourage this transition.展开更多
Due to the correlation and diversity of robotic kinematic dexterity indexes, the principal component analysis （PCA） and kernel principal component analysis （KPCA） based on linear dimension reduction and nonlinear ...Due to the correlation and diversity of robotic kinematic dexterity indexes, the principal component analysis （PCA） and kernel principal component analysis （KPCA） based on linear dimension reduction and nonlinear dimension reduction principle could be respectively introduced into comprehensive kinematic dexterity performance evaluation of space 3R robot of different tasks. By comparing different dimension reduction effects, the KPCA method could deal more effectively with the nonlinear relationship among different single kinematic dexterity indexes, and its calculation result is more reasonable for containing more comprehensive information. KPCA＇ s calculation provides scientific basis for optimum order of robotic tasks, and furthermore a new optimization method for robotic task selection is proposed based on various performance indexes.展开更多
In the field of medical equipment and equipment storage work, when we access accessories and equipment, due to the actual conditions, it causes low efficiency. It is often difficult to quickly and efficiently search b...In the field of medical equipment and equipment storage work, when we access accessories and equipment, due to the actual conditions, it causes low efficiency. It is often difficult to quickly and efficiently search by using simple data management software, such as excel. In order to solve the problem, our team used Python development tool to build high-performance retrieval software, which enabled the equipment custodian to maintain or redesign the database according to actual needs. Through actual verification, this system not only can greatly improve the accuracy of device access, but also has good expansion portability, which could manage various multimedia data systems.展开更多
Robot-assisted technologies are being investigated to overcome the limitations of the current solutions for transoral surgeries,which suffer from constrained insertion ports,lengthy and indirect passageways,and narrow...Robot-assisted technologies are being investigated to overcome the limitations of the current solutions for transoral surgeries,which suffer from constrained insertion ports,lengthy and indirect passageways,and narrow anatomical structures.This paper reviews distal dexterity mechanisms,variable stiffness mechanisms,and triangulation mechanisms,which are closely related to the specific technical challenges of transoral robotic surgery(TORS).According to the structure features in moving and orienting end effectors,the distal dexterity designs can be classified into 4 categories:serial mechanism,continuum mechanism,parallel mechanism,and hybrid mechanism.To ensure adequate adaptability,conformability,and safety,surgical robots must have high flexibility,which can be achieved by varying the stiffness.Variable stiffness(VS)mechanisms based on their working principles in TORS include phase-transitionbased VS mechanism,jamming-based VS mechanism,and structure-based VS mechanism.Triangulations aim to obtain enough workspace and create adequate traction and counter traction for various operations,including visualization,retraction,dissection,and suturing,with independently controllable manipulators.The merits and demerits of these designs are discussed to provide a reference for developing new surgical robotic systems(SRSs)capable of overcoming the limitations of existing systems and addressing challenges imposed by TORS procedures.展开更多
After stroke,even high-functioning individuals may experience compromised bimanual coordination and fine motor dexterity,leading to reduced functional independence.Bilateral arm training has been proposed as a promisi...After stroke,even high-functioning individuals may experience compromised bimanual coordination and fine motor dexterity,leading to reduced functional independence.Bilateral arm training has been proposed as a promising intervention to address these deficits.However,the neural basis of the impairment of functional fine motor skills and their relationship to bimanual coordination performance in stroke patients remains unclear,limiting the development of more targeted interventions.To address this gap,our study employed functional near-infrared spectroscopy to investigate cortical responses in patients after stroke as they perform functional tasks that engage fine motor control and coordination.Twenty-four high-functioning patients with ischemic stroke(7 women,17 men;mean age 64.75±10.84 years)participated in this cross-sectional observational study and completed four subtasks from the Purdue Pegboard Test,which measures unimanual and bimanual finger and hand dexterity.We found significant bilateral activation of the sensorimotor cortices during all Purdue Pegboard Test subtasks,with bimanual tasks inducing higher cortical activation than the assembly subtask.Importantly,patients with better bimanual coordination exhibited lower cortical activation during the other three Purdue Pegboard Test subtasks.Notably,the observed neural response patterns varied depending on the specific subtask.In the unaffected hand task,the differences were primarily observed in the ipsilesional hemisphere.In contrast,the bilateral sensorimotor cortices and the contralesional hemisphere played a more prominent role in the bimanual task and assembly task,respectively.While significant correlations were found between cortical activation and unimanual tasks,no significant correlations were observed with bimanual tasks.This study provides insights into the neural basis of bimanual coordination and fine motor skills in high-functioning patients after stroke,highlighting task-dependent neural responses.The findings also suggest that patients who exhibit better bimanual performance demonstrate more efficient cortical activation.Therefore,incorporating bilateral arm training in post-stroke rehabilitation is important for better outcomes.The combination of functional near-infrared spectroscopy with functional motor paradigms is valuable for assessing skills and developing targeted interventions in stroke rehabilitation.展开更多
To improve the grinding quality of robotic belt grinding systems for the workpieces with complex shaped surfaces, new concepts of the dexterity grinding point and the dexterity grinding space are proposed and their ma...To improve the grinding quality of robotic belt grinding systems for the workpieces with complex shaped surfaces, new concepts of the dexterity grinding point and the dexterity grinding space are proposed and their mathematical descriptions are defined. Factors influencing the dexterity grinding space are analyzed. And a method to determine the necessary dexterity grinding space is suggested. Based on particle swarm optimization （PSO） method, a strategy to optimize the grinding robot structural dimensions and position with respect to the grinding wheel is put forward to obtain the necessary dexterity grinding space. Finally, to grind an aerial engine blade, a dedicated PPPRRR （P： prismatic R： rotary） grinding robot structural dimensions and position with respect to the grinding wheel are optimized using the above strategy. According to simulation results, if the blade is placed within the dexterity grinding space, only one gripper and one grinding machine are needed to grind its complex shaped surfaces.展开更多
China has become a favorite service outsourcing destination for the developed world and the Suzhou Industrial Park is one example of the growing service outsourcing hubs in the country
Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to en...Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to enable the master hand exoskeleton to capture the motion of human fingers and reproduce the contact force between the slave hand and its object.This paper presents a novel finger exoskeleton based on the cascading four-link closed-loop kinematic chain.Each finger has an independent closed-loop kinematic chain,and the angle sensors are used to obtain the finger motion including the flexion/extension and the adduction/abduction.The cable tension is changed by the servo motor to transmit the contact force to the fingers in real time.Based on the finger exoskeleton,an adaptive hand exoskeleton is consequently developed.In addition,the hand exoskeleton is tested in a master-slave system.The experiment results show that the adaptive hand exoskeleton can be worn without any mechanical constraints,and the slave hand can follow the motions of each human finger.The accuracy and the real-time capability of the force reproduction are validated.The proposed adaptive hand exoskeleton can be employed as the master hand to remotely control the humanoid five-fingered dexterous slave hand,thus,enabling the teleoperation system to complete complex dexterous manipulation tasks.展开更多
Most gait studies of multi-legged robots in past neglected the dexterity of robot body and the relationship between stride length and body height.This paper investigates the performance of a radial symmetrical hexapod...Most gait studies of multi-legged robots in past neglected the dexterity of robot body and the relationship between stride length and body height.This paper investigates the performance of a radial symmetrical hexapod robot based on the dexterity of parallel mechanism.Assuming the constraints between the supporting feet and the ground with hinges,the supporting legs and the hexapod body are taken as a parallel mechanism,and each swing leg is regarded as a serial manipulator.The hexapod robot can be considered as a series of hybrid serial-parallel mechanisms while walking on the ground.Locomotion performance can be got by analyzing these equivalent mechanisms.The kinematics of the whole robotic system is established,and the influence of foothold position on the workspace of robot body is analyzed.A new method to calculate the stride length of multi-legged robots is proposed by analyzing the relationship between the workspaces of two adjacent equivalent parallel mechanisms in one gait cycle.Referring to service region and service sphere,weight service sphere and weight service region are put forward to evaluate the dexterity of robot body.The dexterity of single point in workspace and the dexterity distribution in vertical and horizontal projection plane are demonstrated.Simulation shows when the foothold offset goes up to 174 mm,the dexterity of robot body achieves its maximum value 0.164 4 in mixed gait.The proposed methods based on parallel mechanisms can be used to calculate the stride length and the dexterity of multi-legged robot,and provide new approach to determine the stride length,body height,footholds in gait planning of multi-legged robot.展开更多
This paper presents a comparison study of workspace and dexterity of two Tricept units for Reconfigurable Parallel Kinematic Machines （RPKMs）. The modular leg of RPKMs is designed and the RPKMs can be built by chang...This paper presents a comparison study of workspace and dexterity of two Tricept units for Reconfigurable Parallel Kinematic Machines （RPKMs）. The modular leg of RPKMs is designed and the RPKMs can be built by changing tile setting of modules. A compositive kinematic model is developed accordingly. The inverse kinematics and Jacobian of these two Trieept units are analyzed. Considering workspaee volume and dexterity, the effeets of geometric size of some modules on the two Trieept units are discussed. In the end, comparison results of these two Tricept units are. given. The eomparison of two kinds of Parallel Kinematic Machines （PKMs） can be of help in the design and configuration planning of the RPKMs.展开更多
Background: The Box and Block clinical test is a validated and standardized scale for use in the clinical environment that allows the assessment of rough manipulative dexterity. Proposing virtual methods to carry out ...Background: The Box and Block clinical test is a validated and standardized scale for use in the clinical environment that allows the assessment of rough manipulative dexterity. Proposing virtual methods to carry out these assessments is an attempt to eliminate some of the subjectivity that the test may entail depending on the observer and the way in which the patient gives instructions. Applied to the assessment of skills after neurological pathologies, previous experiences in stroke patients have been found. So, this work was centered on the Spinal Cord Injury. Objective: To present the virtual application of the Box and Block scale, as well as details about its design and development for its manipulation based on Leap Motion Controller. Methodology: The relationship between the results obtained in the actual test and in the virtual application in healthy subjects and, mostly, patients with cervical spinal cord injury is analyzed, obtaining a high correlation index between both tests’ performance. Results: A high correlation index was obtained between both tests performance, the real and virtual version of the Box and Block Test. Conclusion: This virtual test can serve as an element to evaluate in the future the effectiveness of the RehabHand prototype based on virtual reality applications with a therapeutic and a rehabilitative sense that, manipulated from Leap Motion Controller, allow the improvement of the manipulative dexterity in patients with neurological diseases such as spinal cord injury.展开更多
将高量子效率的磷光材料fac-tris-2-phenylpyridine iri dium(Ⅲ)(Ir(ppy)_3)按不同的比例掺杂到具有载流子传输能力的主体材料poly(N-vinylcarbazole)(PVK)中作为发光层制备磷光电致发光器件。通过对器件发光机制的研究,发现光致发光...将高量子效率的磷光材料fac-tris-2-phenylpyridine iri dium(Ⅲ)(Ir(ppy)_3)按不同的比例掺杂到具有载流子传输能力的主体材料poly(N-vinylcarbazole)(PVK)中作为发光层制备磷光电致发光器件。通过对器件发光机制的研究,发现光致发光过程中起主导作用的是Foster能量转移机制;而在电致发光过程中,器件的发光性能受Dexter能量转移和电荷陷获2种能量传递形式的影响。器件的I-V-L特性表明:Ir(ppy)_3的掺杂比例为5%时,器件的光功率效率最大,能量转移最充分。展开更多
文摘Ying Chao,born in the 1990s in Jiaxing City of east China’s Zhejiang Province,is of the opinion that traditional agricultural methods cannot meet the demands of modern farming.He plans to change agricultural practices and follow the road of mechanisation after taking part in a one-year vocational training course on drones in Jiaxing Vocational and Technical College in 2021.In fact,more and more young people like Ying are applying digital technology and big data to agricultural production and rural development.And the government has laid out plans to encourage this transition.
基金Supported by the National Natural Science Foundation of China(No.51075005)the Beijing City Science and Technology Project(No.Z131100005313009)
文摘Due to the correlation and diversity of robotic kinematic dexterity indexes, the principal component analysis （PCA） and kernel principal component analysis （KPCA） based on linear dimension reduction and nonlinear dimension reduction principle could be respectively introduced into comprehensive kinematic dexterity performance evaluation of space 3R robot of different tasks. By comparing different dimension reduction effects, the KPCA method could deal more effectively with the nonlinear relationship among different single kinematic dexterity indexes, and its calculation result is more reasonable for containing more comprehensive information. KPCA＇ s calculation provides scientific basis for optimum order of robotic tasks, and furthermore a new optimization method for robotic task selection is proposed based on various performance indexes.
文摘In the field of medical equipment and equipment storage work, when we access accessories and equipment, due to the actual conditions, it causes low efficiency. It is often difficult to quickly and efficiently search by using simple data management software, such as excel. In order to solve the problem, our team used Python development tool to build high-performance retrieval software, which enabled the equipment custodian to maintain or redesign the database according to actual needs. Through actual verification, this system not only can greatly improve the accuracy of device access, but also has good expansion portability, which could manage various multimedia data systems.
基金funded by the National Key R&D Program of China under Grant 2018YFB1307700(with subprogram 2018YFB1307703)from the Ministry of Science and Technology of Chinathe Key Project under Grant 2021B1515120035 of the Regional Joint Fund Project of the Basic and Applied Research Fund of Guangdong Province,Singapore Academic Research Fund under Grant R397000353114,Hong Kong Research Grants Council(RGC)Collaborative Re search Fund under Grant CRF C4026-21GF,General Research Fund(GRF 14216022)Shenzhen-Hong Kong-Macao Technology Research Programme(Type C)under Grant 202108233000303。
文摘Robot-assisted technologies are being investigated to overcome the limitations of the current solutions for transoral surgeries,which suffer from constrained insertion ports,lengthy and indirect passageways,and narrow anatomical structures.This paper reviews distal dexterity mechanisms,variable stiffness mechanisms,and triangulation mechanisms,which are closely related to the specific technical challenges of transoral robotic surgery(TORS).According to the structure features in moving and orienting end effectors,the distal dexterity designs can be classified into 4 categories:serial mechanism,continuum mechanism,parallel mechanism,and hybrid mechanism.To ensure adequate adaptability,conformability,and safety,surgical robots must have high flexibility,which can be achieved by varying the stiffness.Variable stiffness(VS)mechanisms based on their working principles in TORS include phase-transitionbased VS mechanism,jamming-based VS mechanism,and structure-based VS mechanism.Triangulations aim to obtain enough workspace and create adequate traction and counter traction for various operations,including visualization,retraction,dissection,and suturing,with independently controllable manipulators.The merits and demerits of these designs are discussed to provide a reference for developing new surgical robotic systems(SRSs)capable of overcoming the limitations of existing systems and addressing challenges imposed by TORS procedures.
基金supported by the National Key R&D Program of China,No.2020YFC2004202(to DX).
文摘After stroke,even high-functioning individuals may experience compromised bimanual coordination and fine motor dexterity,leading to reduced functional independence.Bilateral arm training has been proposed as a promising intervention to address these deficits.However,the neural basis of the impairment of functional fine motor skills and their relationship to bimanual coordination performance in stroke patients remains unclear,limiting the development of more targeted interventions.To address this gap,our study employed functional near-infrared spectroscopy to investigate cortical responses in patients after stroke as they perform functional tasks that engage fine motor control and coordination.Twenty-four high-functioning patients with ischemic stroke(7 women,17 men;mean age 64.75±10.84 years)participated in this cross-sectional observational study and completed four subtasks from the Purdue Pegboard Test,which measures unimanual and bimanual finger and hand dexterity.We found significant bilateral activation of the sensorimotor cortices during all Purdue Pegboard Test subtasks,with bimanual tasks inducing higher cortical activation than the assembly subtask.Importantly,patients with better bimanual coordination exhibited lower cortical activation during the other three Purdue Pegboard Test subtasks.Notably,the observed neural response patterns varied depending on the specific subtask.In the unaffected hand task,the differences were primarily observed in the ipsilesional hemisphere.In contrast,the bilateral sensorimotor cortices and the contralesional hemisphere played a more prominent role in the bimanual task and assembly task,respectively.While significant correlations were found between cortical activation and unimanual tasks,no significant correlations were observed with bimanual tasks.This study provides insights into the neural basis of bimanual coordination and fine motor skills in high-functioning patients after stroke,highlighting task-dependent neural responses.The findings also suggest that patients who exhibit better bimanual performance demonstrate more efficient cortical activation.Therefore,incorporating bilateral arm training in post-stroke rehabilitation is important for better outcomes.The combination of functional near-infrared spectroscopy with functional motor paradigms is valuable for assessing skills and developing targeted interventions in stroke rehabilitation.
基金National Natural Science Foundation of China （51075013） Beijing Natural Science Foundation （4102035）+1 种基金 Fundamental Research Funds for the Central Universities （YWF-10-01-A09） Research Foundation of State Key Laboratory for Manufacturing Systems Engineering （Xi＇an Jiaotong University）
文摘To improve the grinding quality of robotic belt grinding systems for the workpieces with complex shaped surfaces, new concepts of the dexterity grinding point and the dexterity grinding space are proposed and their mathematical descriptions are defined. Factors influencing the dexterity grinding space are analyzed. And a method to determine the necessary dexterity grinding space is suggested. Based on particle swarm optimization （PSO） method, a strategy to optimize the grinding robot structural dimensions and position with respect to the grinding wheel is put forward to obtain the necessary dexterity grinding space. Finally, to grind an aerial engine blade, a dedicated PPPRRR （P： prismatic R： rotary） grinding robot structural dimensions and position with respect to the grinding wheel are optimized using the above strategy. According to simulation results, if the blade is placed within the dexterity grinding space, only one gripper and one grinding machine are needed to grind its complex shaped surfaces.
文摘China has become a favorite service outsourcing destination for the developed world and the Suzhou Industrial Park is one example of the growing service outsourcing hubs in the country
基金Supported by National Key Research and Development Program of China(Grant No.2018YFE0125600)Zhejiang Provincial Key Research,Develop-ment Program(Grant No.2021C04015)Natural Science Foundation of Zhejiang(Grant No.LZ23E050005).
文摘Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to enable the master hand exoskeleton to capture the motion of human fingers and reproduce the contact force between the slave hand and its object.This paper presents a novel finger exoskeleton based on the cascading four-link closed-loop kinematic chain.Each finger has an independent closed-loop kinematic chain,and the angle sensors are used to obtain the finger motion including the flexion/extension and the adduction/abduction.The cable tension is changed by the servo motor to transmit the contact force to the fingers in real time.Based on the finger exoskeleton,an adaptive hand exoskeleton is consequently developed.In addition,the hand exoskeleton is tested in a master-slave system.The experiment results show that the adaptive hand exoskeleton can be worn without any mechanical constraints,and the slave hand can follow the motions of each human finger.The accuracy and the real-time capability of the force reproduction are validated.The proposed adaptive hand exoskeleton can be employed as the master hand to remotely control the humanoid five-fingered dexterous slave hand,thus,enabling the teleoperation system to complete complex dexterous manipulation tasks.
基金Supported by National Science Foundation for Distinguished Young Scholar,China(Grant No.51125020)National Natural Science Foundation of China(Grant No.51305009)CAST Foundation
文摘Most gait studies of multi-legged robots in past neglected the dexterity of robot body and the relationship between stride length and body height.This paper investigates the performance of a radial symmetrical hexapod robot based on the dexterity of parallel mechanism.Assuming the constraints between the supporting feet and the ground with hinges,the supporting legs and the hexapod body are taken as a parallel mechanism,and each swing leg is regarded as a serial manipulator.The hexapod robot can be considered as a series of hybrid serial-parallel mechanisms while walking on the ground.Locomotion performance can be got by analyzing these equivalent mechanisms.The kinematics of the whole robotic system is established,and the influence of foothold position on the workspace of robot body is analyzed.A new method to calculate the stride length of multi-legged robots is proposed by analyzing the relationship between the workspaces of two adjacent equivalent parallel mechanisms in one gait cycle.Referring to service region and service sphere,weight service sphere and weight service region are put forward to evaluate the dexterity of robot body.The dexterity of single point in workspace and the dexterity distribution in vertical and horizontal projection plane are demonstrated.Simulation shows when the foothold offset goes up to 174 mm,the dexterity of robot body achieves its maximum value 0.164 4 in mixed gait.The proposed methods based on parallel mechanisms can be used to calculate the stride length and the dexterity of multi-legged robot,and provide new approach to determine the stride length,body height,footholds in gait planning of multi-legged robot.
文摘This paper presents a comparison study of workspace and dexterity of two Tricept units for Reconfigurable Parallel Kinematic Machines （RPKMs）. The modular leg of RPKMs is designed and the RPKMs can be built by changing tile setting of modules. A compositive kinematic model is developed accordingly. The inverse kinematics and Jacobian of these two Trieept units are analyzed. Considering workspaee volume and dexterity, the effeets of geometric size of some modules on the two Trieept units are discussed. In the end, comparison results of these two Tricept units are. given. The eomparison of two kinds of Parallel Kinematic Machines （PKMs） can be of help in the design and configuration planning of the RPKMs.
文摘Background: The Box and Block clinical test is a validated and standardized scale for use in the clinical environment that allows the assessment of rough manipulative dexterity. Proposing virtual methods to carry out these assessments is an attempt to eliminate some of the subjectivity that the test may entail depending on the observer and the way in which the patient gives instructions. Applied to the assessment of skills after neurological pathologies, previous experiences in stroke patients have been found. So, this work was centered on the Spinal Cord Injury. Objective: To present the virtual application of the Box and Block scale, as well as details about its design and development for its manipulation based on Leap Motion Controller. Methodology: The relationship between the results obtained in the actual test and in the virtual application in healthy subjects and, mostly, patients with cervical spinal cord injury is analyzed, obtaining a high correlation index between both tests’ performance. Results: A high correlation index was obtained between both tests performance, the real and virtual version of the Box and Block Test. Conclusion: This virtual test can serve as an element to evaluate in the future the effectiveness of the RehabHand prototype based on virtual reality applications with a therapeutic and a rehabilitative sense that, manipulated from Leap Motion Controller, allow the improvement of the manipulative dexterity in patients with neurological diseases such as spinal cord injury.
文摘将高量子效率的磷光材料fac-tris-2-phenylpyridine iri dium(Ⅲ)(Ir(ppy)_3)按不同的比例掺杂到具有载流子传输能力的主体材料poly(N-vinylcarbazole)(PVK)中作为发光层制备磷光电致发光器件。通过对器件发光机制的研究,发现光致发光过程中起主导作用的是Foster能量转移机制;而在电致发光过程中,器件的发光性能受Dexter能量转移和电荷陷获2种能量传递形式的影响。器件的I-V-L特性表明:Ir(ppy)_3的掺杂比例为5%时,器件的光功率效率最大,能量转移最充分。
